CLOSURE WITH GASKET

FIELD OF THE INVENTION

The present invention relates generally to the field of container assemblies. In one embodiment, the present invention relates specifically to a plastic container having a large diameter opening and a lugged metal closure and gasket combination configured to provide an air-tight seal for contents stored within the container while maintaining the shape of the neck while the closure is sealed to the neck.

SUMMARY OF THE INVENTION

In one embodiment, a closure is configured for used with a plastic container. The closure comprises a circular top panel and a skirt extending downwardly from an outer periphery of the top panel. At least five metallic lugs are spaced about and extend radially inwardly from a lower portion of the skirt. The lugs are configured to engage plastic threads formed on a neck of the container.

Each of the lugs comprises a front end and a rear end. The front end of each lug extends further radially inwards than the rear end of each lug. The lugs extend along a non-zero angle between the front end and the rear end

The closure has a diameter of at least 28 mm. Each lug has a length as defined in a circumferential direction of between 0.5 inches and 1.5 inches. A

A gasket is attached to and extends about at least a portion of a lower surface of the top panel. The gasket has a permanent deformation of between approximately 30% and 70% as measured under conditions in which a specimen of the gasket is compressed by approximately 25% for a period of twenty-two (22) hours at a temperature of 158° F., and is subsequently allowed to cool for 30 minutes.

In one embodiment, a closure is configured for used with container. The closure comprises a circular top panel and a skirt extending downwardly from an outer periphery of the top panel. Five or more lugs are spaced about and extend radially inwardly from a lower portion of the skirt. The lugs are configured to engage threads formed on a neck of the container.

The closure has a diameter of at least 28 mm. Each lug occupies between 5 percent and 15 percent of a perimeter defined by the lower portion of the skirt. A midpoint of each lug is spaced no more than approximately 72 degrees form a midpoint of an adjacent lug, as measured from a center of the closure.

A gasket is attached to and extends about at least a portion of a lower surface of the top panel. The gasket is formed of a material comprising at least one polymer. The gasket is configured such that, following a hot filling process of up to 100° C. for up to 60 minutes the gasket retains the ability to provide a hermetic seal for contents of a container to which the closure is attached. The gasket further is configured such that there is less than less than 60 ppb of components forming the gasket material that migrate into the contents of the container following the hot-fill process.

In one embodiment a method of forming a closure comprises providing a closure having a circular top panel having an upper surface and a lower surface. A channel is formed in and extends circumferentially about a portion of the lower surface of the top panel configured to overlie a mouth of a container to which the closure is configured to be applied. A skirt extends downwardly from an outer periphery of the top panel.

A plurality of lugs are spaced about a lower portion of the skirt. The lugs extend radially inwardly towards a center of the closure such that at least a portion of each lug extends over and blocks access to at least a portion of the lower surface of the top panel. The closure has a diameter of at least 28 mm.

A gasket-forming material is extruded onto the lower surface of the top panel. The gasket-forming material is sufficiently flowable such that at least a portion of the extruded material flows into and fills the channel to form a gasket that is configured to engage and seal the mouth of the container. The gasket-forming material is extruded onto the top panel subsequent to the lugs being formed.

The gasket formed from the gasket-forming material has a permanent deformation of between approximately 30% and 70% as measured under conditions in which a specimen of the gasket is compressed by approximately 25% for a period of twenty-two (22) hours at a temperature of 158° F., and is subsequently allowed to cool for 30 minutes.

BRIEF DESCRIPTION OF THE DRAWINGS

This application will become more fully understood from the following detailed description, taken in conjunction with the accompanying figures, wherein like reference numerals refer to like elements in which:

FIG. 1 is an enlarged view of a seal interface between a closure and a neck portion of a container according to one embodiment; and

FIG. 2 is an enlarged view of a seal interface between a closure and a neck portion of a container according to another embodiment.

DETAILED DESCRIPTION

In one embodiment, a container assembly is provided comprising a container, a closure configured to seal the container, and a gasket configured to provide an air-tight seal between the closure and the container.

In one embodiment, the closure comprises a metal closure having a circular, closure panel having an internal surface extending to a periphery. A concentric channel extends from the periphery along an angled wall into a parallel wall generally parallel to the closure panel. The parallel wall extends into a first rounded wall having a center of radius within the closure. The parallel wall is offset from the closure panel by a first distance. A concentric flange extends from the first rounded wall into a second rounded wall having a center of radius external to the closure into a transition wall which extends into a third rounded wall having a center of radius within the closure. The first rounded wall transitions into the second rounded wall at a second distance from the periphery that is at least 2 times as large as the first distance. A cylindrical skirt extends from the concentric flange. At least 4 equally spaced rolled flanges extend from the cylindrical skirt. At least one lug is located between each pair of rolled flanges, and a resilient polymeric gasket fills the concentric channel.

In one embodiment, the closure is a metal closure and includes a closure panel having an internal surface extending to a periphery. A vacuum indicating panel is located at the center of the internal surface. A concentric channel extends from the periphery along an angled wall into a parallel wall generally parallel to the closure panel. The parallel wall extends into a first rounded wall having a center of radius within the closure. The parallel wall is offset from the closure panel by a first distance.

The radii of the first and second rolled walls are smaller than the radius of the third rolled wall. The angle between the angled wall and the parallel wall is between 20 and 75 degrees. The transition wall is generally parallel to the closure panel and the parallel wall. A plane passing through the transition wall is displaced further from the parallel wall than the closure panel.

A cylindrical skirt extending from the concentric flange. At least 4 equally spaced rolled flanges extend from the cylindrical skirt. At least one lug is located between each pair of rolled flanges. Each lug includes a tapered, rolled surface which facilitates sliding of the lug relative to a thread on a respective container neck, and a resilient polymeric gasket fills the concentric channel.

In one embodiment, a sealed container includes a plastic container including a threaded neck which provides an opening to the container. The neck includes generally parallel internal and external walls terminating at a sealing edge or lip. A metal closure includes a circular, closure panel having an internal surface extending to a periphery. A vacuum indicating panel is located at the center of the internal surface. A concentric channel extends from the periphery along an angled wall into a parallel wall generally parallel to the closure panel. The parallel wall extends into a first rounded wall having a center of radius within the closure. The parallel wall is offset from the closure panel by a first distance.

A concentric flange extends from the first rounded wall into a second rounded wall having a center of radius external to the closure into a transition wall which extends into third rounded wall having a center of radius within the closure. The first rounded wall transitions into the second rounded wall at a second distance from the periphery. The second distance is at least 2 times as large as the first distance. The radii of the first and second rolled walls are smaller than the radius of the third rolled wall. The transition wall is generally parallel to the closure panel and the parallel wall. A plane passing through the transition wall is displaced further from the parallel wall than the closure panel. A cylindrical skirt extends from the concentric flange. At least 4 equally spaced rolled flanges extend from the cylindrical skirt.

At least one thread engagement flange located between each pair of rolled flanges. The engagement flanges include a tapered, rolled tip which facilitates sliding of the engagement flanges relative to a thread on a respective container neck. A resilient polymeric material fills the concentric channel. The tapered, rolled tips are engaged with the threaded neck so that the sealing edge is forced into the polymeric material so that polymeric material engages the sealing edge to resist deformation of the neck when forces between the tips and threaded neck are sufficient to seal the closure to the neck.

In one embodiment, a metal closure comprises multiple thread engaging lugs, and in one embodiment the lug design is configured to decrease the pressure exerted by the closure lugs on the neck finish of the container.

In one embodiment, a metal closure comprises a top wall, a skirt and a plurality of lugs. The skirt extends downwards from a peripheral edge of the top wall. A first end of the skirt is attached to the top wall. A second end of the skirt is defined by a lower edge. The lower edge is radially defined between an exterior surface and an interior surface. The closure includes a plurality of radially inwardly extending lugs located at positions about the lower edge. The interior surface of the lower edge at the positions of the lugs extend radially inwards relative to the interior surface of the lower edge of the skirt adjacent the lugs; The plurality of lugs occupy at least 25% of the length of the perimeter of the lower edge.

In one embodiment, a metal closure comprises a top wall, a sidewall, and a plurality of lugs. The top wall has a center point that lies along a central axis. The top wall is concentrically disposed about the central axis. The sidewall extends downward along its length from a peripheral edge of the top wall to a lower edge. The plurality of lugs, the top wall, and sidewall are formed from a single contiguous piece of metal. The lugs are deformed sections the sidewall that extend radially inwards towards the central axis. Adjacent lugs are separated from each other by undeformed portions of the sidewall. Adjacent lugs are separated from each other by undeformed portions of the sidewall. Each lug has a first end and a second end spaced from the first end in the circumferential direction. The angular distance between the first end and second end of each lug as measured from the central axis is at least 30°.

In one embodiment, the metal closure comprises a top wall, a skirt, and a plurality of lugs. The skirt extends downward from a peripheral edge of the top wall. The skirt includes a lower edge. At least five lugs are formed at the lower edge of the skirt.

In one embodiment, a filled container assembly including a container having a polymeric body and a polymeric finish which includes a plurality of threads. The closure includes a plurality of metallic lugs configured to cooperate with the plurality of threads to couple the closure to the polymeric finish. A gasket is configured to provide a seal between the closure and container. The container assembly in configured to withstand temperatures of up to 270° F.

In one embodiment, a method for producing a closure having at least five lugs and having a polymer-based sealing element comprises heating a polymer-based sealing element until the sealing element is made sufficiently flowable. The sealing element has a Shore A hardness in a range from 40 to 90 and a permanent deformation in a range from 30% to 70% determined after 25% compression at 70° C., after 22 h. The sealing element is applied to the closure in such a manner that the sealing element sealingly abuts the opening of a closure in a closed state. The sealing element comprises no PVC. The sealing element comprises a polymer material comprising a poly(alkylene), and is configured for use with a closure having a diameter of at least 28 mm. The sealing element is shaped by stamping in a preformed closure blank.

In one embodiment, a method for producing a closure having at least five lugs and a polymer-based sealing element comprises heating a polymer-based sealing element until the sealing element is made sufficiently flowable. The sealing element has a Shore A hardness in a range from 40 to 90 and a permanent deformation in a range from 30% to 70% determined after 25% compression at 70° C., after 22 h. The sealing element is applied to the closure in such a manner that the sealing element sealingly abuts the opening of a closure in a closed state. The sealing element comprises no PVC. The sealing element comprises a polymer material comprising a poly(alkylene), and is configured for use with a closure having a diameter of at least 28 mm. The sealing element is shaped by stamping in a preformed closure blank. The closure has a gas barrier effect and/or an overpressure valve effect in the closed state, and the closure may provide a vacuum retention when secured to a container.

In one embodiment, a method for producing a closure having at least five lugs and having a polymer-based sealing element comprises heating a polymer compound to make it sufficiently flowable. The polymer compound is applied to the closure in the region the gasket is to be produced. The polymer compound is brought mechanically into the desired shape which is maintained after it has cooled. The Shore A hardness of the polymer compound is in the range of 40 to 90 and the polymer compound shows a permanent deformation between 30% and 70% determined after 25% compression at 70° C., after 22 h. The polymer compound is PVC-free and comprises a block copolymer which on the one hand comprises polyethylene units and on the other hand is built up from an alkene monomer, selected from the group consisting of propene, butene, hexene and octene, in the range of 20% to less than 100%; The polymer compound is also formed of a random copolymer that is composed of a linear or branched interpolymer of ethylene on the one hand and at least one C₃-C₂₀alpha-olefin on the other hand, in the range of less than 80%. The polymer compound may comprise other polyolefins up to 25%.

In one embodiment, a method for producing a closure having at least five lugs and having a polymer-based sealing element comprises heating a polymer compound to make it sufficiently flowable. The polymer compound is applied to the closure in the region the gasket is to be produced. The polymer compound is brought mechanically into the desired shape which is maintained after it has cooled. The Shore A hardness of the polymer compound is in the range of 60 to 75 and the polymer compound shows a permanent deformation between 30% and 70% determined after 25% compression at 70° C., after 22 h.

In one embodiment, a method for producing a closure having at least five lugs and having a polymer-based sealing element comprises heating a polymer compound to make it sufficiently flowable. The polymer material is provided as a granulate and is heated by an extruder. The polymer compound is applied to the closure in the region the gasket is to be produced. The flowable polymer material may be applied by a nozzle onto the inner side of the closure. The polymer compound is brought mechanically into the desired shape which is maintained after it has cooled. In one embodiment, the applied polymer material is shaped by a stamp or the like. The Shore A hardness of the polymer compound is in the range of 40 to 90 and the polymer compound shows a permanent deformation between 30% and 70% determined after 25% compression at 70° C., after 22 h. The polymer compound is PVC-free and comprises a block copolymer which on the one hand comprises polyethylene units and on the other hand is built up from an alkene monomer, selected from the group consisting of propene, butene, hexene and octene, in the range of 20% to less than 100%; The polymer compound is also formed of a random copolymer that is composed of a linear or branched interpolymer of ethylene on the one hand and at least one C₃-C₂₀alpha-olefin on the other hand, in the range of less than 80%. The polymer compound may comprise other polyolefins up to 25%.

In one embodiment, a closure having at least five lugs is provided with a PVC free gasket. The gasket comprises a polymer-based composition, comprising: 10 to 40% thermoplastic elastomer (TPE) based on styrene-ethylene-butylene-styrene (SEBS); at least one polyolefin component; and white oil in an amount of not more than 50%. The Shore A hardness of the polymer-based composition is in the range of 50 to 90 and the polymer-based composition exhibits a permanent deformation between 30% and 90% determined after 25% compression at 70° C., after 22 h. The polymer-based composition further comprises a lubricant in an amount not more than 4%.

In one embodiment, a closure having at least five lugs is provided with a PVC free gasket. The gasket comprises a polymer-based composition, comprising: 10 to 40% thermoplastic elastomer (TPE) based on styrene-ethylene-butylene-styrene (SEBS); at least one polyolefin component; and white oil in an amount of not more than 50%. The Shore A hardness of the polymer-based composition is in the range of 50 to 90 and the polymer-based composition exhibits a permanent deformation between 30% and 90% determined after 25% compression at 70° C., after 22 h. The polyolefin comprises between 10% to 30% linear low-density polyethylene polyethylene (LLDPE).

In one embodiment, a closure having at least five lugs is provided with a PVC free gasket. The gasket comprises a polymer-based composition, comprising: 10 to 40% thermoplastic elastomer (TPE) based on styrene-ethylene-butylene-styrene (SEBS); at least one polyolefin component; and white oil in an amount of not more than 50%. The Shore A hardness of the polymer-based composition is in the range of 50 to 90 and the polymer-based composition exhibits a permanent deformation between 30% and 90% determined after 25% compression at 70° C., after 22 h. The polyolefin comprises between 5% to 25% low density polyethylene (LDPE).

In one embodiment, a closure having at least five lugs is provided with a PVC free gasket. The gasket comprises a polymer-based composition, comprising: 10 to 40% thermoplastic elastomer (TPE) based on styrene-ethylene-butylene-styrene (SEBS); at least one polyolefin component; and white oil in an amount of not more than 50%. The Shore A hardness of the polymer-based composition is in the range of 50 to 90 and the polymer-based composition exhibits a permanent deformation between 30% and 90% determined after 25% compression at 70° C., after 22 h. The polyolefin comprises between 2% to 20% copolymer consisting of polypropylene and polyethylene.

In one embodiment, a closure having at least five lugs is provided with a PVC free gasket. The gasket comprises a polymer-based composition, comprising: 10 to 40% thermoplastic elastomer (TPE) based on styrene-ethylene-butylene-styrene (SEBS); at least one polyolefin component; and white oil in an amount of not more than 50%. The Shore A hardness of the polymer-based composition is in the range of 50 to 90 and the polymer-based composition exhibits a permanent deformation between 30% and 90% determined after 25% compression at 70° C., after 22 h. The polyolefin comprises at least 20% of (a) a block copolymer that is an interpolymer of

ethylene and at least one C₃-C₂₀alpha-olefin or (b) a copolymer of ethylene and one C₃-C₂₀alpha-olefin, in either case optionally in combination with other unsaturated monomers.

In one embodiment, a closure having at least five lugs is provided with a PVC free gasket. The gasket comprises a polymer-based composition, comprising: 10 to 40% thermoplastic elastomer (TPE) based on styrene-ethylene-butylene-styrene (SEBS); at least one polyolefin component; and white oil in an amount of not more than 50%. The Shore A hardness of the polymer-based composition is in the range of 50 to 90 and the polymer-based composition exhibits a permanent deformation between 30% and 90% determined after 25% compression at 70° C., after 22 h. The polymer-based composition comprises between 20% to 45% medicinal white oil. In some embodiments, the polymer-based composition comprises between 20% to 45% medicinal white oil.

In one embodiment, a closure having at least five lugs is provided with a PVC free gasket. The gasket comprises a polymer-based composition, comprising: 10 to 40% thermoplastic elastomer (TPE) based on styrene-ethylene-butylene-styrene (SEBS); at least one polyolefin component; and white oil in an amount of not more than 50%. The Shore A hardness of the polymer-based composition is in the range of 50 to 90 and the polymer-based composition exhibits a permanent deformation between 30% and 90% determined after 25% compression at 70° C., after 22 h. The block copolymer has a density of 0.85 to 01.1 g/cm3, a melt flow index (MFI) of 0.01 g/10 min to 1000 g/10 min, and a gravimetric load of 5 kg. In one embodiment, the block copolymer has a melt flow index (MFI) of 1 g/10 min to 100 g/10 min at 190° C.

In one embodiment, a closure having at least five lugs is provided with a gasket. The gasket is formed from a PVC free polymer based composition that comprises at least one oxygen-scavenging substance; 10 to 40 wt % thermoplastic elastomer (TPE) based on styrene-ethylene-butylenestyrene (SEBS); at least one polyolefin component selected from the group consisting of 2 to 20 wt % copolymer consisting of polypropylene and polyethylene, 5 to 25 wt % low-density polyethylene (LDPE), 10-30 wt % linear low-density polyethylene (LLDPE), and combinations thereof; and white oil. The Shore A hardness of the polymer-based composition is between 50 to 90, and in one embodiment a Shore A hardness of between 60 to 80. The polymer based composition exhibits a permanent deformation between 30% and 90% determined after 25% compression at 70° C., after 22 h.

In one embodiment, a closure having at least five lugs is provided with a gasket. The gasket is formed from a PVC free polymer based composition that comprises at least one oxygen-scavenging substance; 10 to 40 wt % thermoplastic elastomer (TPE) based on styrene-ethylene-butylenestyrene (SEBS); at least one polyolefin component selected from the group consisting of 2 to 20 wt % copolymer consisting of polypropylene and polyethylene, 5 to 25 wt % low-density polyethylene (LDPE), 10-30 wt % linear low-density polyethylene (LLDPE), and combinations thereof; and white oil. The Shore A hardness of the polymer-based composition is between 50 to 90. The polymer based composition exhibits a permanent deformation between 30% and 90% determined after 25% compression at 70° C., after 22 h. The polymer-based composition comprises sodium sulfite as the oxygen scavenging substance, with an average particle size smaller than 20 microns.

In one embodiment, a closure having at least five lugs is provided with a gasket. The gasket is formed from a PVC free polymer based composition that comprises at least one oxygen-scavenging substance; 10 to 40 wt % thermoplastic elastomer (TPE) based on styrene-ethylene-butylenestyrene (SEBS); at least one polyolefin component selected from the group consisting of 2 to 20 wt % copolymer consisting of polypropylene and polyethylene, 5 to 25 wt % low-density polyethylene (LDPE), 10-30 wt % linear low-density polyethylene (LLDPE), and combinations thereof; and white oil. The Shore A hardness of the polymer-based composition is between 50 to 90. The polymer based composition exhibits a permanent deformation between 30% and 90% determined after 25% compression at 70° C., after 22 h. The polymer-based composition comprises between 1% to 10% sodium sulfite as oxygen-scavenging substance.

In one embodiment, a closure having at least five lugs is provided with a gasket. The gasket is formed from a PVC free polymer based composition that comprises at least one oxygen-scavenging substance; 10 to 40 wt % thermoplastic elastomer (TPE) based on styrene-ethylene-butylenestyrene (SEBS); at least one polyolefin component selected from the group consisting of 2 to 20 wt % copolymer consisting of polypropylene and polyethylene, 5 to 25 wt % low-density polyethylene (LDPE), 10-30 wt % linear low-density polyethylene (LLDPE), and combinations thereof; and white oil. The Shore A hardness of the polymer-based composition is between 50 to 90. The polymer based composition exhibits a permanent deformation between 30% and 60% determined after 25% compression at 70° C., after 22 h.

In one embodiment, a closure having at least five lugs is provided with a gasket. The gasket is formed from a PVC free polymer based composition that comprises at least one oxygen-scavenging substance; 10 to 40 wt % thermoplastic elastomer (TPE) based on styrene-ethylene-butylenestyrene (SEBS); at least one polyolefin component selected from the group consisting of 2 to 20 wt % copolymer consisting of polypropylene and polyethylene, 5 to 25 wt % low-density polyethylene (LDPE), 10-30 wt % linear low-density polyethylene (LLDPE), and combinations thereof; and white oil. The Shore A hardness of the polymer-based composition is between 50 to 90. The polymer based composition exhibits a permanent deformation between 30% and 90% determined after 25% compression at 70° C., after 22 h. The at least one polyolefin component comprises between 5% to 15% copolymer consisting of polypropylene (PP) and polyethylene (PE).

In one embodiment, a closure having at least five lugs is provided with a gasket. The gasket is formed from a PVC free polymer based composition that comprises at least one oxygen-scavenging substance; 10 to 40 wt % thermoplastic elastomer (TPE) based on styrene-ethylene-butylenestyrene (SEBS); at least one polyolefin component selected from the group consisting of 2 to 20 wt % copolymer consisting of polypropylene and polyethylene, 5 to 25 wt % low-density polyethylene (LDPE), 10-30 wt % linear low-density polyethylene (LLDPE), and combinations thereof; and white oil. The Shore A hardness of the polymer-based composition is between 50 to 90. The polymer based composition exhibits a permanent deformation between 30% and 90% determined after 25% compression at 70° C., after 22 h. The at least one poly olefin component comprises between 10% to 20% low density polyethylene.

In one embodiment, a closure having at least five lugs is provided with a gasket. The gasket is formed from a PVC free polymer based composition that comprises at least one oxygen-scavenging substance; 10 to 40 wt % thermoplastic elastomer (TPE) based on styrene-ethylene-butylenestyrene (SEBS); at least one polyolefin component selected from the group consisting of 2 to 20 wt % copolymer consisting of polypropylene and polyethylene, 5 to 25 wt % low-density polyethylene (LDPE), 10-30 wt % linear low-density polyethylene (LLDPE), and combinations thereof; and white oil. The Shore A hardness of the polymer-based composition is between 50 to 90. The polymer based composition exhibits a permanent deformation between 30% and 90% determined after 25% compression at 70° C., after 22 h. The polymer-based composition comprises not more than 10% of lubricants.

In one embodiment, a closure having at least five lugs is provided with a gasket. The gasket is formed from a PVC free polymer based composition that comprises at least one oxygen-scavenging substance; 10 to 40 wt % thermoplastic elastomer (TPE) based on styrene-ethylene-butylenestyrene (SEBS); at least one polyolefin component selected from the group consisting of 2 to 20 wt % copolymer consisting of polypropylene and polyethylene, 5 to 25 wt % low-density polyethylene (LDPE), 10-30 wt % linear low-density polyethylene (LLDPE), and combinations thereof; and white oil. The Shore A hardness of the polymer-based composition is between 50 to 90. The polymer based composition exhibits a permanent deformation between 30% and 90% determined after 25% compression at 70° C., after 22 h. The thermoplastic elastomers based on styrene-ethylene-butylene-styrene have a fixed styrene content of 31%.

In one embodiment, a closure having at least five lugs is provided with a gasket. The gasket is formed from a PVC free polymer based composition that comprises at least one oxygen-scavenging substance; 10 to 40 wt % thermoplastic elastomer (TPE) based on styrene-ethylene-butylenestyrene (SEBS); at least one polyolefin component selected from the group consisting of 2 to 20 wt % copolymer consisting of polypropylene and polyethylene, 5 to 25 wt % low-density polyethylene (LDPE), 10-30 wt % linear low-density polyethylene (LLDPE), and combinations thereof; and white oil. The Shore A hardness of the polymer-based composition is between 50 to 90. The polymer based composition exhibits a permanent deformation between 30% and 90% determined after 25% compression at 70° C., after 22 h. The polymer-based composition comprises between 20% to 45% medicinal white oil.

In one embodiment, a closure having at least five lugs is provided with a gasket. The gasket is formed from a PVC free polymer based composition that comprises at least one oxygen-scavenging substance; 10 to 40 wt % thermoplastic elastomer (TPE) based on styrene-ethylene-butylenestyrene (SEBS); at least one polyolefin component selected from the group consisting of 2 to 20 wt % copolymer consisting of polypropylene and polyethylene, 5 to 25 wt % low-density polyethylene (LDPE), 10-30 wt % linear low-density polyethylene (LLDPE), and combinations thereof; and white oil. The Shore A hardness of the polymer-based composition is between 50 to 90. The polymer based composition exhibits a permanent deformation between 30% and 90% determined after 25% compression at 70° C., after 22 h. The at least one polyolefin component comprises between 15% to 25% linear low density polyethylene.

In one embodiment, a closure having at least five lugs is provided with a gasket. The gasket is formed from a PVC free polymer based composition that comprises at least one oxygen-scavenging substance; 10 to 40 wt % thermoplastic elastomer (TPE) based on styrene-ethylene-butylenestyrene (SEBS); at least one polyolefin component selected from the group consisting of 2 to 20 wt % copolymer consisting of polypropylene and polyethylene, 5 to 25 wt % low-density polyethylene (LDPE), 10-30 wt % linear low-density polyethylene (LLDPE), and combinations thereof; and white oil. The Shore A hardness of the polymer-based composition is between 50 to 90. The polymer based composition exhibits a permanent deformation between 30% and 90% determined after 25% compression at 70° C., after 22 h. The gasket exhibits opening values in the range of 0.678 Nm (6 lbf.in) to 1.130 Nm (10 lbf.in) with a target value of 0.791 Nm (7 lbf.in) before and after pasteurization.

In one embodiment, a closure having at least five lugs is provided with a gasket. The gasket is formed from a PVC free polymer based composition that comprises at least one oxygen-scavenging substance; 10 to 40 wt % thermoplastic elastomer (TPE) based on styrene-ethylene-butylenestyrene (SEBS); at least one polyolefin component selected from the group consisting of 2 to 20 wt % copolymer consisting of polypropylene and polyethylene, 5 to 25 wt % low-density polyethylene (LDPE), 10-30 wt % linear low-density polyethylene (LLDPE), and combinations thereof; and white oil. The Shore A hardness of the polymer-based composition is between 50 to 90. The polymer based composition exhibits a permanent deformation between 30% and 90% determined after 25% compression at 70° C., after 22 h. The gasket exhibits a pressure maintenance of higher than 8 bar after pasteurization.

In one embodiment, a closure having at least five lugs is provided with a gasket. The gasket is formed from a PVC free polymer based composition that comprises at least one oxygen-scavenging substance; 10 to 40 wt % thermoplastic elastomer (TPE) based on styrene-ethylene-butylenestyrene (SEBS); at least one polyolefin component selected from the group consisting of 2 to 20 wt % copolymer consisting of polypropylene and polyethylene, 5 to 25 wt % low-density polyethylene (LDPE), 10-30 wt % linear low-density polyethylene (LLDPE), and combinations thereof; and white oil. The Shore A hardness of the polymer-based composition is between 50 to 90. The polymer based composition exhibits a permanent deformation between 30% and 90% determined after 25% compression at 70° C., after 22 h. The polymer-based composition comprises between 20 to 30 wt % styreneethylene-butylene-styrene.

In one embodiment, a closure having at least five lugs is provided with a gasket. The gasket is formed from a PVC free polymer based composition that comprises at least one oxygen-scavenging substance; 10 to 40 wt % thermoplastic elastomer (TPE) based on styrene-ethylene-butylenestyrene (SEBS); at least one polyolefin component selected from the group consisting of 2 to 20 wt % copolymer consisting of polypropylene and polyethylene, 5 to 25 wt % low-density polyethylene (LDPE), 10-30 wt % linear low-density polyethylene (LLDPE), and combinations thereof; and white oil. The Shore A hardness of the polymer-based composition is between 50 to 90. The polymer based composition exhibits a permanent deformation between 30% and 90% determined after 25% compression at 70° C., after 22 h. The polymer-based composition comprises additives. In one embodiment, the additives comprise waxes, silicones, or combinations thereof.

In one embodiment, a closure having at least five lugs and a gasket is configured for being used with a container containing a food or beverage products. The gasket is made of a seal material which comprises at least one polymer mixed with further substances. The seal material contains no PVC and substantially no crosslinked polymers. The seal material is substantially free from components that are liquid at application temperature. The gasket can be pasteurized at temperatures up to 98° C. The seal material has a Shore hardness between 40 and 95. The seal material comprises at least three different polymers, of which the first is a substantially thermoplastic polymer, whereas the two other polymers are different plastic thermoplastics or thermoplastic elastomers.

In one embodiment, a closure having at least five lugs and a gasket is configured for being used with a container containing a food or beverage products. The gasket is made of a seal material which comprises at least one polymer mixed with further substances. The seal material contains no PVC and substantially no crosslinked polymers. The seal material is substantially free from components that are liquid at application temperature. The gasket can be pasteurized at temperatures up to 98° C. The seal material, as a primary component, comprises a poly(ethylene-co-propylene) with a density at 23° C. (ISO 1183) of 0.86-0.9 g/cm³and a melt flow rate under conditions of 230° C./2.16 kg (MFR, ISO 1133) of 25-29 g/10 min at a Shore D hardness (15 sec, ISO 868) of 25-30, as a primary component.

In one embodiment, a closure having at least five lugs and a gasket is configured for being used with a container containing a food or beverage products. The gasket is made of a seal material which comprises at least one polymer mixed with further substances. The seal material contains no PVC and substantially no crosslinked polymers. The gasket can be pasteurized at temperatures up to 98° C. The seal material, in relation to the total weight of the seal material, comprises a minimum content of 5% by weight of styrene-based block copolymer and a minimum content of 10% by weight of a propylene polymer and/or propylene copolymer, and optionally at least one oil component.

In one embodiment, a closure having at least five lugs and a gasket is configured for being used with a container containing a food or beverage products. The gasket is made of a seal material which comprises at least one polymer mixed with further substances. The seal material contains no PVC and substantially no crosslinked polymers. The seal material is substantially free from components that are liquid at application temperature. The gasket can be pasteurized at temperatures up to 98° C. The seal material has a Shore A hardness between 40 and 95. The seal material comprises at least three different polymers, of which the first is a substantially thermoplastic polymer, whereas the two other polymers are different plastic thermoplastics or thermoplastic elastomers. In the closed state, the closure has a gas barrier effect and/or the effect of a pressure relief valve.

In one embodiment, a closure having at least five lugs and a gasket is configured for being used with a container containing a food or beverage products. The gasket is made of a seal material which comprises at least one polymer mixed with further substances. The seal material contains no PVC and substantially no crosslinked polymers. The seal material is substantially free from components that are liquid at application temperature. The gasket can be pasteurized at temperatures up to 98° C. The seal material has a Shore A hardness between 40 and 95. The seal material comprises at least three different polymers, of which the first is a substantially thermoplastic polymer, whereas the two other polymers are different plastic thermoplastics or thermoplastic elastomers. In the closed state, the closure demonstrates vacuum retention.

In one embodiment, a closure having at least five lugs and a gasket is configured for being used with a container containing a food or beverage products. The gasket is made of a seal material which comprises at least one polymer mixed with further substances. The seal material contains no PVC and substantially no crosslinked polymers. The seal material is substantially free from components that are liquid at application temperature. The gasket can be pasteurized at temperatures up to 98° C. The seal material has a Shore A hardness between 40 and 95. The seal material comprises at least three different polymers, of which the first is a substantially thermoplastic polymer, whereas the two other polymers are different plastic thermoplastics or thermoplastic elastomers. The seal material contains no more than 50% of components that are liquid at application temperature.

In one embodiment, a closure having at least five lugs and a gasket is configured for being used with a container containing a food or beverage products. The gasket is made of a seal material which comprises at least one polymer mixed with further substances. The seal material contains no PVC and substantially no crosslinked polymers. The seal material is substantially free from components that are liquid at application temperature. The gasket can be pasteurized at temperatures up to 98° C. The seal material has a Shore A hardness between 40 and 95. The seal material comprises at least three different polymers, of which the first is a substantially thermoplastic polymer, whereas the two other polymers are different plastic thermoplastics or thermoplastic elastomers. The seal material exhibits a permanent deformation between 25% and 90% determined after 25% compression at 70° C., after 22 h.

In one embodiment, a closure having at least five lugs and a gasket is configured for being used with a container containing a food or beverage products The gasket is made of a seal material which comprises at least one polymer mixed with further substances. The seal material contains no PVC and substantially no crosslinked polymers. The seal material is substantially free from components that are liquid at application temperature. The gasket can be pasteurized at temperatures up to 98° C. The seal material has a Shore A hardness between 40 and 95. The seal material comprises at least three different polymers, of which the first is a substantially thermoplastic polymer, whereas the two other polymers are different plastic thermoplastics or thermoplastic elastomers. The seal material contains between 0.1 and 80% of at least one block copolymer. The block copolymer is an interpolymer of ethylene with at least one C₃-C₂₀alpha olefin or a copolymer of ethylene with a C₃-C₂₀alpha olefin, optionally in combination with other unsaturated monomers. In one embodiment, the block copolymer has a density from 0.80 to 1.1 g/cm³and a melt flow index (MFI) from 0.01 g/10 min to 1,000 g/10 min, with a production of 5 kg at 190° C.

In one embodiment, a closure having at least five lugs and a gasket is configured for being used with a container containing a food or beverage products The gasket is made of a seal material which comprises at least one polymer mixed with further substances. The seal material contains no PVC and substantially no crosslinked polymers. The seal material is substantially free from components that are liquid at application temperature. The gasket can be pasteurized at temperatures up to 98° C. The seal material has a Shore A hardness between 40 and 95. The seal material comprises at least three different polymers, of which the first is a substantially thermoplastic polymer, whereas the two other polymers are different plastic thermoplastics or thermoplastic elastomers. The seal material contains between 0.1% and 80% of at least one random copolymer, wherein the random copolymer is a linear interpolymer of ethylene and a C₃-C₂₀alpha olefin or a branched interpolymer of ethylene and C₃-C₂₀alpha olefin. In one embodiment, the random copolymer has a density from 0.80 to 1.1 g/cm³and a melt flow index (MFI) from 0.15 g/10 min to 100 g/10 min. In one embodiment the random copolymer comprises two alkenes selected from the group consisting of ethylene, propene, butene, hexene and octene.

In one embodiment, a closure having at least five lugs and a gasket is configured for being used with a container containing a food or beverage products The gasket is made of a seal material which comprises at least one polymer mixed with further substances. The seal material contains no PVC and substantially no crosslinked polymers. The seal material is substantially free from components that are liquid at application temperature. The gasket can be pasteurized at temperatures up to 98° C. The seal material has a Shore A hardness between 40 and 95. The seal material comprises at least three different polymers, of which the first is a substantially thermoplastic polymer, whereas the two other polymers are different plastic thermoplastics or thermoplastic elastomers. The seal material contains between 5% and 70% of SEBS and between 10% and 50% of a propylene(co)polymer. In one embodiment, the seal material contains between 5% and 50% of white oil.

In one embodiment, a closure having at least five lugs and a gasket is configured for being used with a container containing a food or beverage products The gasket is made of a seal material which comprises at least one polymer mixed with further substances. The seal material contains no PVC and substantially no crosslinked polymers. The seal material is substantially free from components that are liquid at application temperature. The gasket can be pasteurized at temperatures up to 98° C. The seal material has a Shore A hardness between 40 and 95. The seal material comprises at least three different polymers, of which the first is a substantially thermoplastic polymer, whereas the two other polymers are different plastic thermoplastics or thermoplastic elastomers. The seal material comprises between 20% and 50% of SEBS, and up to 25% of polyethylene, up to 50% of PP and/or up to 50% of PP-based elastomer.

In one embodiment, a closure having at least five lugs and a gasket is configured for being used with a container containing a food or beverage products. The gasket is made of a seal material which comprises at least one polymer mixed with further substances. The seal material contains no PVC and substantially no crosslinked polymers. The seal material is substantially free from components that are liquid at application temperature. The gasket can be pasteurized at temperatures up to 98° C. The seal material has a Shore A hardness between 40 and 95. The seal material comprises at least three different polymers, of which the first is a substantially thermoplastic polymer, whereas the two other polymers are different plastic thermoplastics or thermoplastic elastomers. The seal material comprises a polyester.

In one embodiment, a closure having at least five lugs comprises a gasket. The gasket is formed from a PVC free polymer-containing composition. The polymer-containing composition comprises a blend comprising of at least one polymer that has barrier properties to oxygen and volatile compounds; at least one oxygen depleting compound; and optionally at least one additive. The polymer-containing composition contains no more than 10% by weight of an oil; has a Shore D hardness of at least 20; and a melt flow index (190° C., 5 kg) of at least 5. The polymer is a non-cross linked barrier polymer and the polymer-containing composition has a Shore D hardness from 20 to 60 and a melt flow index (190° C., 5 kg) from 5 to 25. In one embodiment, the non-cross linked barrier polymer is selected from the group consisting of butyl rubber, polyisoprene, polyisobutylene, styrene isoprene butadiene (SIBS), polybutene, and polyolefin. In one embodiment, the non-cross linked barrier polymer is present in an amount of between 10% to 50% by weight of the polymer-containing composition.

In one embodiment, a closure having at least five lugs comprises a gasket. The gasket is formed from a PVC free polymer-containing composition. The polymer-containing composition comprises a blend comprising of at least one polymer that has barrier properties to oxygen and volatile compounds; at least one oxygen depleting compound; and optionally at least one additive. The polymer-containing composition contains no more than 10% by weight of an oil; has a Shore D hardness of at least 20; and a melt flow index (190° C., 5 kg) of at least 5. The polymer is a non-cross linked barrier polymer and the polymer-containing composition has a Shore D hardness from 20 to 60 and a melt flow index (190° C., 5 kg) from 5 to 25. The polymer-containing composition further comprises a second polymer which is a polyolefin. The polymer-containing composition further comprises at least one softer polymer, which reduces the total hardness (Shore D) of the polymer-containing composition, as compared to a corresponding polymer-containing composition that does not contain the at least one softer polymer.

In one embodiment, a closure having at least five lugs comprises a gasket. The gasket is formed from a PVC free polymer-containing composition. The polymer-containing composition comprises a blend comprising of at least one polymer that has barrier properties to oxygen and volatile compounds; at least one oxygen depleting compound; and optionally at least one additive. The polymer-containing composition contains no more than 10% by weight of an oil; has a Shore D hardness of at least 20; and a melt flow index (190° C., 5 kg) of at least 5. The polymer is a non-cross linked barrier polymer and the polymer-containing composition has a Shore D hardness from 20 to 60 and a melt flow index (190° C., 5 kg) from 5 to 25. The polymer-containing composition further comprises a second polymer which is a polyolefin. The polymer-containing composition further comprises at least one softer polymer, which reduces the total hardness (Shore D) of the polymer-containing composition, as compared to a corresponding polymer-containing composition that does not contain the at least one softer polymer. The softer polymer is a low density polyethylene (LDPE), which is present in an amount between 5% to 25% by weight of the polymer-containing composition, or linear low density polyethylene (LLDPE), which is present in an amount of up to 30% by weight of the polymer-containing composition.

In one embodiment, a closure having at least five lugs comprises a gasket. The gasket is formed from a PVC free polymer-containing composition. The polymer-containing composition comprises a blend comprising of at least one polymer that has barrier properties to oxygen and volatile compounds; at least one oxygen depleting compound; and optionally at least one additive. The polymer-containing composition contains no more than 10% by weight of an oil; has a Shore D hardness of at least 20; and a melt flow index (190° C., 5 kg) of at least 5. The polymer is a non-cross linked barrier polymer and the polymer-containing composition has a Shore D hardness from 20 to 60 and a melt flow index (190° C., 5 kg) from 5 to 25. The polymer-containing composition further comprises a second polymer which is a polyolefin. The polymer-containing composition further comprises at least one softer polymer, which reduces the total hardness (Shore D) of the polymer-containing composition, as compared to a corresponding polymer-containing composition that does not contain the at least one softer polymer. In one embodiment, the softer polymer is a block copolymer, which is present in an amount of up to 25% by weight of the polymer-containing composition. In one embodiment, the block copolymer is an interpolymer of ethylene with at least one C3-C10-alpha-olefin or a copolymer of ethylene with a C3-C20 alpha-olefin optionally in combination with other unsaturated monomers.

In one embodiment, a closure having at least five lugs comprises a gasket. The gasket is formed from a PVC free polymer-containing composition. The polymer-containing composition comprises a blend comprising of at least one polymer that has barrier properties to oxygen and volatile compounds; at least one oxygen depleting compound; and optionally at least one additive. The polymer-containing composition contains no more than 10% by weight of an oil; has a Shore D hardness of at least 20; and a melt flow index (190° C., 5 kg) of at least 5. The polymer is a non-cross linked barrier polymer and the polymer-containing composition has a Shore D hardness from 20 to 60 and a melt flow index (190° C., 5 kg) from 5 to 25. The polymer-containing composition further comprises a second polymer which is a polyolefin. The polymer-containing composition further comprises at least one softer polymer, which reduces the total hardness (Shore D) of the polymer-containing composition, as compared to a corresponding polymer-containing composition that does not contain the at least one softer polymer. The softer polymer is EVA, which is present in an amount of at least 5% by weight of the polymer containing composition. In one embodiment, the polymer-containing composition further comprises a block copolymer, which is present in an amount of up to 25% by weight of the polymer-containing composition.

contains up to 80% by weight of the second polymer. In one embodiment, the second polymer is high-density polyethylene (HDPE).

In one embodiment, a closure having at least five lugs comprises a gasket. The gasket is formed from a PVC free polymer-containing composition. The polymer-containing composition comprises a blend comprising of at least one polymer that has barrier properties to oxygen and volatile compounds; at least one oxygen depleting compound; and optionally at least one additive. The polymer-containing composition contains no more than 10% by weight of an oil; has a Shore D hardness of at least 20; and a melt flow index (190° C., 5 kg) of at least 5. The polymer is a polyolefin and the polymer-containing composition has a Shore D hardness from 20 to 60 and a melt flow index (190° C., 5 kg) from 5 to 55. The polymer-containing composition further comprises at least one softer polymer, which reduces the total hardness (Shore D) of the polymer-containing composition, as compared to a corresponding polymer-containing composition that does not contain the at least one softer polymer. The softer polymer is a low density polyethylene (LDPE), which is present in an amount between 5% to 25% by weight of the polymer-containing composition, or linear low density polyethylene (LLDPE), which is present in an amount of up to 30% by weight of the polymer-containing composition.

In one embodiment, a closure having at least five lugs comprises a gasket. The gasket is formed from a PVC free polymer-containing composition. The polymer-containing composition comprises a blend comprising of at least one polymer that has barrier properties to oxygen and volatile compounds; at least one oxygen depleting compound; and optionally at least one additive. The polymer-containing composition contains no more than 10% by weight of an oil; has a Shore D hardness of at least 20; and a melt flow index (190° C., 5 kg) of at least 5. The polymer is a polyolefin and the polymer-containing composition has a Shore D hardness from 20 to 60 and a melt flow index (190° C., 5 kg) from 5 to 55. The polymer-containing composition further comprises at least one softer polymer, which reduces the total hardness (Shore D) of the polymer-containing composition, as compared to a corresponding polymer-containing composition that does not contain the at least one softer polymer. The softer polymer is a block copolymer, which is present in an amount of up to 25% by weight of the polymer-containing composition. In one embodiment, the block copolymer is an interpolymer of ethylene with at least one C3-C10-alpha-olefin or a copolymer of ethylene with a C3-C20 alpha-olefin optionally in combination with other unsaturated monomers.

In one embodiment, a closure having at least five lugs comprises a gasket. The gasket is formed from a PVC free polymer-containing composition. The polymer-containing composition comprises a blend comprising of at least one polymer that has barrier properties to oxygen and volatile compounds; at least one oxygen depleting compound; and optionally at least one additive. The polymer-containing composition contains no more than 10% by weight of an oil; has a Shore D hardness of at least 20; and a melt flow index (190° C., 5 kg) of at least 5. The polymer is a polyolefin and the polymer-containing composition has a Shore D hardness from 20 to 60 and a melt flow index (190° C., 5 kg) from 5 to 55. The polymer-containing composition further comprises at least one softer polymer, which reduces the total hardness (Shore D) of the polymer-containing composition, as compared to a corresponding polymer-containing composition that does not contain the at least one softer polymer. The softer polymer is EVA, which is present in an amount of at least 5% by weight of the polymer containing composition. In one embodiment, the polymer-containing composition further comprises a block copolymer, which is present in an amount of up to 25% by weight of the polymer-containing composition.

In one embodiment, a closure having at least five lugs comprises a gasket. The gasket is formed from a PVC free seal material. The seal material is composed such that the gasket withstands a sterilization at temperatures of above 100° C. and up to 132° C. The gasket, in a dynamic mechanical thermal analysis (DMTA), demonstrates a heating curve for the phase angle tan (delta), the inflection point of which lies above the required sterilization temperature. The seal material contains no PVC and substantially no crosslinked polymers. The seal material is substantially free from components that are liquid at application temperature. The seal material has a Shore A hardness between 40 and 95. The seal material comprises at least three different polymers, of which the first is a substantially thermoplastic polymer, whereas the two other polymers are different plastic thermoplastics or thermoplastic elastomers.

In one embodiment, a closure having at least five lugs comprises a gasket. The gasket is formed from a PVC free seal material. The seal material is composed such that the gasket withstands a sterilization at temperatures of above 100° C. and up to 132° C. The gasket, in a dynamic mechanical thermal analysis (DMTA), demonstrates a heating curve for the phase angle tan (delta), the inflection point of which lies above the required sterilization temperature. The seal material contains between 0.1 and 80% of at least one block copolymer, wherein the block copolymer is an interpolymer of ethylene with at least one C₃-C₂₀alpha olefin or a copolymer of ethylene with a C₃-C₂₀alpha olefin, optionally in combination with other unsaturated monomers. The block copolymer has a density from 0.85 to 1.1 g/cm³and a melt flow index (MFI) from 0.01 g/10 min to 1,000 g/10 min, with a production of 5 kg at 190° C.

In one embodiment, a closure having at least five lugs comprises a gasket. The gasket is formed from a PVC free seal material. The seal material is composed such that the gasket withstands a sterilization at temperatures of above 100° C. and up to 132° C. The gasket, in a dynamic mechanical thermal analysis (DMTA), demonstrates a heating curve for the phase angle tan (delta), the inflection point of which lies above the required sterilization temperature. The seal material contains between 0.1 and 80% of at least one block copolymer, wherein the block copolymer is an interpolymer of ethylene with at least one C₃-C₂₀alpha olefin or a copolymer of ethylene with a C₃-C₂₀alpha olefin, optionally in combination with other unsaturated monomers. The seal material contains between 0.1% and 80% of at least one random copolymer, wherein the random copolymer is a linear interpolymer of ethylene and a C₃-C₂₀alpha olefin or a branched interpolymer of ethylene and a C₃-C₂₀alpha olefin. In one embodiment, the random copolymer has a density from 0.85 to 1.1 g/cm³and a melt flow index (MFI) from 0.15 g/10 min to 100 g/10 min. In one embodiment, the random copolymer comprises two alkenes selected from the group consisting of ethylene, propene, butene, hexene and octene.

In one embodiment, a closure having at least five lugs comprises a gasket. The gasket is formed from a PVC free seal material. The seal material is composed such that the gasket withstands a sterilization at temperatures of above 100° C. and up to 132° C. The gasket, in a dynamic mechanical thermal analysis (DMTA), demonstrates a heating curve for the phase angle tan (delta), the inflection point of which lies above the required sterilization temperature. The seal material contains between 0.1 and 80% of at least one block copolymer, wherein the block copolymer is an interpolymer of ethylene with at least one C₃-C₂₀alpha olefin or a copolymer of ethylene with a C₃-C₂₀alpha olefin, optionally in combination with other unsaturated monomers. The seal material contains between 5% and 70% of SEBS and between 10% and 50% of a propylene(co)polymer. In one embodiment, the seal material contains between 5% and 50% of white oil. In one embodiment the seal material comprises between 20% and 50% of SEBS, and up to 25% of polyethylene, up to 50% of PP, and/or up to 50% of PP-based elastomer.

In one embodiment, a closure having at least five lugs comprises a gasket. The gasket is formed from a PVC free seal material. The gasket can be pasteurized at temperatures up to 98° C. and can be sterilized at temperatures up to 132° C. The seal material comprises a thermoplastic elastomer (TPE), and optionally a PP or (co)PP and/or an oil component.

In one embodiment, a container assembly includes a container, a closure and a gasket. The container includes a polymeric body and a polymeric finish. The polymeric finish includes a plurality of threads and a strengthening member associated with each one of the plurality of threads that extends from an exterior surface of the finish to provide the polymeric finish with an increased thickness. The closure includes a plurality of metallic lugs configured to cooperate with the plurality of threads to couple the metallic closure to the polymeric finish. The gasket is configured to provide an air-tight seal between the metallic closure and the polymeric finish when the closure is attached to the container. Each one of the plurality of metallic lugs includes a leading end and a trailing end, the leading end extends further towards a center of the closure than the trailing end.

As plastic containers are lightweight, inexpensive, recyclable, and manufacturable in large quantities, in one embodiment, the container of the container assembly comprises a plastic container that may be made from any suitable polymer including polypropylene (PP), polyethylene terephthalate (PET), high-density polyethylene (HDPE), low-density polyethylene (LDPE), polyethylene naphthalate (PEN), a PET/PEN blend or copolymer, multilayer polymer structures, etc. In other embodiments, the container may be formed or any other number of materials, including but not limited to glass, metal, etc.

In some embodiments, the closure may be made of any suitable metallic material, such as steel, tin, or aluminum. In other embodiments, the closure may be made of any other number or suitable materials. The closure may comprise any variety of known closure structures such as, but not limited to: threaded screw cap, lug cap, crown cap, roll-on, press-on pry-off, etc. In a preferred embodiment, the container assembly comprises a metallic lug closure coupled to a PET container.

The container may have any suitable size and shape and can be configured to store any suitable liquid or solid therein, including food or beverage products. In embodiments in which the container is used to store food or beverage products, the container may be configured to be used with hot-fill, pasteurization and sterilization processes of up to 270° F.

The container may comprise an opening defined by a lip and a bottom surface. A neck portion comprising a plurality of threads extending therefrom may extend downwards from the lip towards the bottom surface. The threads may be made of the same material as the neck portion and/or the body of the container. In one embodiment, the threads are made from PET.

Each thread may include a leading end and a trailing end, with the leading ends being located closer to the lip than to the container bottom surface. The trailing ends are closer to the bottom surface than the lip of the container. Each thread is thus generally angled and slopes downward toward the bottom surface of the container from the leading end to the trailing end. The threads have a thread pitch angle or beta helix angle of between 5 degrees and 7 degrees, specifically is about 6 degrees and more specifically is 6 degrees, 6 minutes.

Each thread further includes an upper surface facing the lip and an undersurface generally facing the bottom surface. The threads are shaped and positioned to allow the closure to be threaded on and off of neck portion and also facilitate lower pressure sealing provided by the closure. In some embodiments, the threads are arranged such that the leading end of each thread overlaps the trailing end of an adjacent thread.

Any suitable number of threads can be included on the container neck portion. The number of threads will typically correspond to the number of lugs (described below) formed on the closure. In some embodiments, the number of threads may vary depending on the diameter of the container opening. In some embodiments, the container comprises an opening having a diameter of 58 mm and three or four threads extending from the neck portion. In one embodiment, the container comprises an opening having a diameter of 63 mm and four to six threads extending from the neck portion. In some embodiment, the container comprises an opening having a diameter of 70 mm and five to seven threads extending from the neck portion. In some embodiment, the container comprises an opening having a diameter of 82 mm and five to nine threads extending from the neck portion.

In some embodiments, a plurality of strengthening members may be formed on and extend outwardly from the exterior surface of the neck portion. In some embodiments, the strengthening members extend outwards from a location corresponding to the trailing end of a thread, with the strengthening members located at areas of the neck portion where neighboring threads overlap one another.

In addition to reinforcing the neck portion of the container, the strengthening members may act as thread stops to prevent over-tightening of the closure. Specifically, as the closure is screwed onto the threads, the lugs will be stopped by the strengthening members from moving further along the threads, thereby preventing the closure from being screwed tighter onto the threads and the neck portion.

Disclosed in the paragraphs below are embodiments of a closure having a particular top panel/flange/skirt arrangement that may be used in some embodiment with a container as described above, wherein in certain embodiments the use of a closure as discussed below and a container may comprise the use of a metallic lugged closure as described and a plastic container as described. In other embodiments, the closure having a top panel/flange/skirt arrangement as discussed below may be made of any number of materials and may include any number of engagement structures (i.e. threads, lugs, press-twist, crimp, etc.) and such a closure may be used with a container different that one according to the above described container embodiments.

In one embodiment, the closure includes a circular top panel. Extending about the outer periphery of the top panel is a concentric channel. Extending radially outwards from the channel is a flange from a cylindrical skirt extends downwardly in a direction generally perpendicular to a plane along which the top panel extends.

In some embodiments, the closure top panel may include a centrally located vacuum-indicating panel having a circular center portion, a first annular portion, and a second annular portion. The vacuum-indicating panel is configured to permit the circular center portion move relative to the top panel in response to pressure variations within an associated container to which the closure is attached.

Illustrated in FIG. 1 is one embodiment of a neck portion 30 of a container 11. The neck portion 30 includes an internal wall 34, and external wall 36 on which thread 38 are formed. As discussed above, in some embodiments a plurality of strengthening members (not shown) may also extend radially outwards from the neck portion 30.

The walls 34, 36 terminate at lip 39. Lip 39 may take any form suitable to deflect and engage a gasket 40 in channel 14. FIGS. 1 and 2 illustrate two (2) preferred sealing lip 39 configurations. The configuration of FIG. 1 includes an angled tip 42 for engaging and/or gripping gasket 40 when closure 10 is sealed to container 11. The lip 39 configuration of FIG. 2 includes a hook formation 44 which engages and/or grips gasket 40 when closure 10 is sealed to container 11. In some embodiments, a lip 39 as shown may be incorporated into a container as described above. In other embodiments, containers other than those described above having a lip 39 as described may be used. In yet other embodiments, the closure as representatively illustrated in FIGS. 1 and 2 may be used with containers having upper lip/mouth portions not defined by a lip 39 as shown and described with reference to FIGS. 1 and 2.

When the neck engagement elements 20 of the closure (such as, but not limited to lugs, e.g. as representatively illustrated in FIGS. 1 and 2) apply force to thread 38 of neck portion 30, this force has an inward, radial component which will tend to deflect or distort neck portion 30 from its desired, original, unsealed circular shape. However, closure 10 is configured so that prior to the increase in the radial force component above a level which would distort neck portion 30, lip 39 engages gasket 40 so that concentric channel 14 provides radial support to neck portion 30. This radial support prevents distortion of neck portion 30 as the radial forces are increased to generate an appropriate seal (e.g. hermetic, air-tight, fluid-tight, etc.) between closure 10 and container 11.

The features of closure 10 are useable with any shape neck of a container. For non-circular containers, the closure 10 thread engagement elements 20 would be configured so that closure 10 would be pushed (as opposed to turned) onto the container 11. (Note however, that certain circular threaded closures are pushed onto the circular threads of a corresponding container neck even though the end user twists the cap to open the closed container.)

In the push-on situation, the thread engagement lugs would be further configured for a particular container so that the component of radial force between the engagement elements 20 and neck reaches is maximum level after the lip is sufficiently engaged with the gasket in the channel. Engagement is sufficient when it is able to resist radial deformation of the corresponding neck.

As material costs, manufacturing costs, shipping costs, disposal costs and other costs resulting from the use of materials in containers increase, the need for a closure having the features of closure 10 will increase. Examples of such costs are given above, but there may be other costs incurred during the full life cycle of a closure and container, and this cycle which spans from the time the closure and container are manufactured to the time the closure and container are recycled or disposed.

Further details of an embodiment closure 10 will now be described in reference to FIGS. 1 and 2. Some of these details may be eliminated or modified depending upon factors such as manufacturability, material availability and changes, coatings (PET B&T finish) used on the metal (e.g. coated steel from a roll vs. uncoated steel), container material and use, neck shape, etc. (e.g. circular vs. rectangular, etc.)

The concentric channel 14 is configured so that it contains enough gasket material 40 to permit adequate engagement of lip 39 with the gasket 40 as discussed above. In one embodiment, the channel 14 is formed so that the large cross-sectional width of the gasket is at least 1.5 to 2.5 times the cross-sectional height of the gasket 40 as shown in detail in FIGS. 1 and 2.

Another way to size the channel 14 is about the distance between walls 34, 36 of neck portion 30 (“neck thickness”). By way of example, cross-sectional height of the gasket 40 may be within 90 to 110% of the neck thickness, and the width may be in the range of 150% to 250% of the neck thickness.

The concentric channel 14 extends from the periphery of closure panel 12 along an angled wall 50 into a parallel wall 52 generally parallel to the closure panel 12. The parallel wall 52 extends into a rounded wall 54 having a center of radius within the closure 10. The parallel wall 52 is offset from the closure panel 12. An exemplary range for this offset distance is between 0.051 and 0.068 inches.

The concentric flange 16 extends from the rounded wall 54 and transitions into a second rounded wall 56 having a center of radius external to the closure 10. The transition between walls 54 and 56 includes a flat transition wall which may have an angle from 0 to 15 degrees where the top of this transition wall is closer to the periphery than the bottom of this transition wall. The second rounded wall 56 extends into a transition wall 58 which extends into a third rounded wall 60 having a center of radius within the closure 10. The radii of the rounded walls 54 and 56 are preferably smaller than the radius of the rounded wall 60.

An angle θ₁between the angled wall 50 and the parallel wall 52 may be between 20 and 75 degrees but in one embodiment is 28 degrees. The transition wall 58 is generally parallel to the closure panel 12 and the parallel wall 52. A plane passing through the transition wall 58 (plane not shown) is displaced further from the parallel wall 52 than the closure panel 12. An exemplary range for this displacement distance is between 0.099 and 0.156 inches. In preferred embodiments, this displacement distance will typically vary in accordance with the offset distance discussed above in a ratio of about 2 to 1, displacement distance to offset distance. However, depending upon the particular application for the cap, this ratio could range between 1 to 1, to 3 to 1.

Furthermore, the height of the combination of the walls 54, 56, 58 and 60 (“combination height”) are typically designed relative to a particular container neck. In particular, this height is roughly equal (plus or minus 20%) to the distance from the top of thread 38 to lip 39. As such, referring to FIG. 2, the distance from the bottom of thread 38 (K) minus the thread profile height (TP) equals the combination height (approximately S).

Referring to FIG. 2, exemplary dimensions (in inches), and angles (in degrees) for one embodiment of the closure in the area of the multi-seal sealing structure are provided. These dimensions, angles and radii are exemplary and would be modified within appropriate ranges to accommodate variations such closure size, manufacturing process, mold characteristics, closure material, etc.

The closure is configured to exert a decreased pressure on the neck of a container are shown and described. In general, the metal closure includes a plurality of lugs (e.g., five or more lugs) that have an increased width such that the sealing force is more evenly distributed around the neck portion of the container, thereby decreasing the pressure exerted on the container neck portion by the closure. In some applications, the plastic material of the container may be softened (e.g., by heat from a hot-fill process, steam retort, pasteurization, etc.), and the lower pressure lug design discussed herein acts to decrease or prevent deformation of the plastic material of the container neck portion that may otherwise be caused by a closure with a different, higher pressure lug design (e.g. a closure having fewer and/or shorter lugs).

Described below is one embodiment of a closure having lugs arranged about a lower portion of the closure skirt. In some embodiments, the lug arrangement described below may be incorporated into any of the closure embodiments having a top panel/flange/skirt arrangement as described above. In other embodiments, the lug arrangement described herein may be used with other closures having any other number of top panel, skirt, and optional flange arrangements.

The skirt of the closure is defined by a lower edge or rim that extends in a radial direction between an inner surface and an outer surface of the skirt. In some embodiments, the lower edge of the skirt is formed as a rolled flange. A plurality of lugs are formed at and extend radially inward from the lower edge. In some embodiment, lugs are formed by deforming a curled, rolled or crimped portion of the lower edge. In various embodiments, lugs may also be formed from sections of the skirt that have been deformed to extend radially inwards towards the central axis of the closure, with adjacent lugs separated from each other by undeformed portions of the skirt. In such embodiments, lugs are formed from the same single contiguous piece of metal that forms the rest of the closure.

At those locations along the lower edge about which lugs are formed, the inner surface of the lower edge extends radially inwards from the inner surface of those portions of the lower edge about which no lugs are formed. Additionally, in various embodiments, at those locations along the lower edge where the lugs are formed, the width of the lower edge in a radial direction is greater than the width of the lower edge in a radial direction at locations at which lugs are not formed.

In one embodiment, closure includes more than four lugs, and in one such embodiment closure includes five lugs. Closure includes a plurality of non-lugged, curved sections located between each lug, which are typically formed of the undeformed portion of the skirt. The curvature of the non-lugged, curved sections generally mirrors the curvature of the peripheral edge of the closure top panel. In one embodiment, closure includes more than four non-lugged, curved sections, and in one such embodiment, closure includes five non-lugged, curved sections.

The lugs can be evenly spaced apart along the lower edge, or may be arranged at any other suitable interval. Any suitable number of lugs can be included, such as only five lugs, less than five lugs, or more than five lugs, such as, e.g. six, seven, eight, or more lugs.

In various embodiments, an angle is defined between the midpoints of adjacent lugs. The angle between midpoints is typically no greater than 90 degrees, and preferably no greater than approximately than 80 degrees, and in a specific embodiment, 2 degrees (e.g., 72 degrees plus or minus one (1) degree from the midpoint of an adjacent lug.

The lugs are provided with an increased length to enhance cooperation between the lugs and the threads of the container, and to more easily center the lugs on the threads. In one embodiment, each lug has a length generally in the circumferential direction 5 and 15 percent of the perimeter length of lower edge. In various embodiments, this length is between 0.5 inches and 1.5 inches, and in a specific embodiment, is about between about 0.7 inches and about 0.75 inches. In one such embodiment, the length of the lugs is between about 0.7 inches and 0.75 inches and the diameter of the closure is 63 mm. In some embodiments, the lugs are formed about the lower edge of the skirt such that none of the lugs lie diametrically opposite each other. The closure may be formed of any size, such as, but not limited to diameters of 28 mm, 33 mm, 38 mm, 43 mm, 48 mm, 53 mm, 58 mm, 63 mm, 68, 70 mm, 77 mm, 82 mm, 89 mm, 100 mm, 110 mm, etc.

In various embodiments, the leading and trailing ends of each lug define an angle relative to the center point of closure. In various embodiments, the angular distance between the leading and trailing ends of each lug is between 30 degrees and 50 degrees, specifically is between 35 degrees and 45 degrees and more specifically between 38 degrees and 42 degrees. In one embodiment, the angular distance between the leading and trailing ends of each lug is at least 30 degrees.

In one embodiment, each lug increases the contact area with the neck portion of the container by approximately 72% as compared to a standard four lug metal closure. Thus, in various embodiments, the increased length of the lugs and the increased number of lugs as compared to a standard four lug closure act to better distribute sealing forces around the neck portion of the container sealed by closure, and in some embodiments, this decrease in force acts to limit distortion of the container neck portion.

Extending between the leading and trailing ends of each lug is an intermediate portion. Each lug extends at a radial distance that is closer to the center axis of the closer than the radial distance of the lug at each trailing end (i.e. the leading end of each lug is located radially inwards from the trailing end of each lug). Each lug is angled and/or curved along the intermediate portion in a manner corresponding to an angle and/or curve at which the threads extend about the neck portion of the container so that the lugs will generally continuously mate with the threads along substantially their entire length.

The upper surface of each lug defines a thread engagement surface. In some embodiments, the thread engagement surface of each lug is formed having an angle that generally matches the angle of the threads. When the closure 10 is attached to the container 30, the thread engagement surface 19 of the lugs interfaces with the lower surface 49 of the threads 40 to seal the container 30.

To couple the closure to the container, the lugs are positioned at the threads and the closure is rotated such that the lugs slide along the undersurface of each thread. As the closure is rotated the upper thread engagement surface of the lugs move along the undersurface of the threads, the bottom surface of the top panel of the closure is moved toward the upper lip of the neck portion of the container. In a preferred embodiment, a gasket is provided along at least a portion of the bottom surface of the top panel of the closure. The closure can be rotated until the gasket cannot be further depressed against the lip, or, in embodiments incorporating strengthening members, until the lugs contact the strengthening members at the trailing end of the threads. The gasket is arranged such that the gasket contacts the upper surface of the lip of the container to provide an airtight seal between the closure and the container. A detailed description of various gasket-forming materials and desired gasket properties which may be used with the container assembly is provided below.

The lugs can be formed in any suitable manner to arrange portions of the inner surface of the lower edge of the skirt closer to the center axis closure at portions along the skirt where the lugs are formed, as compared to portions of the skirt where no lugs are formed. For example, any device suitable for pulling or generally moving the lower edge towards the axial center of the closure so that the leading end of the lugs extends further towards the center axis of the closure than the trailing ends of the lugs may be used.

In some embodiments, it may be desirable to apply a coating to all or a portion (e.g. skirt) of closure which improves gripping when closure is metal or another smooth material. Coating the gripping surface of a metal cap/closure with soft-touch polymer can improve the haptics of the gripping surface. The improved gripping surface allows energy to be applied to the rotation and translation with a reduction of force needed for gripping the closure. Suppliers of the soft touch polyurethane coating system are: Alsa Corporation, Sun Chemicals, Valspar and Bayer. Examples of polymer used are polyurethane dispersions, polyester polyurethane dispersions, polycarbonate polyesters, HDI isocyanurates, HDI biuretes, and HDI polyisocyanat. Soft touch coatings may be applied by spraying or applying a film having a soft touch surface thereon.

As described above, in some embodiments the closure may include a gasket formed from a gasket-forming material. The gasket is configured to prevent leakage of the container contents and to seal the contents of the container so as to avoid any unwanted contamination of the contents from pollution caused by substances to which the filled and closed container may be exposed, such as, e.g. during storage and transport. In some embodiment, the gasket may be configured to hermetically seal the container contents.

The gasket may also be used and configured to retain an initial vacuum in the container prior to initial opening of the container. In one embodiment, the gasket is configured such that the gasket can maintain a pressure of more than 8 bar after pasteurization of the container contents.

The gasket is preferably configured with a sufficiently low twist-off value so that the closure may be removed from a container with a moderate amount of force. The gasket may also be configured such that the twist-off value is also not so low so as to cause undesired or unintended opening of the closure. In one embodiment, the twist-off value is in the range of 0.678 Nm to 1.130 Nm, and most preferably, approximately 0.791 Nm.

The gasket is preferably formed of a gasket-forming material that is configured to allow for repeated opening and closing of the container with minimal or no loss of the tightness and/or the opening forces of the gasket. Preferably the gasket is also configured to be capable of maintaining its sealing effect over the intended lifetime (i.e. minimum shelf life) of the contents of the container.

The gasket may be arranged in any number of configurations about the lower surface of the closure. For example, the gasket may extend: along only the lower surface of the top panel of the closure; along only the skirt of the closure; along both the closure top panel and skirt. As described above, some closures may include a channel formed on the lower surface of the closure, and in some embodiment the gasket is located in such a channel.

The gasket may be formed having any number of shapes and/or sizes. For example, the gasket may be formed as a ring that extends only about an outer periphery of the closure, the gasket may be formed as a disc that covers substantially the entire lower surface of the closure top panel, etc. The gasket may have a generally uniform thickness, or may optionally be formed having a varied profile and/or having various thickness at different locations about the gasket. In some embodiment, the gasket may be formed having a sealing ridge or lip extending generally perpendicular to the surface of the gasket and the top panel of the closure to which to the gasket is attached, the ridge extending in a generally downward direction that is parallel to a central axis of the closure.

Preferably, the gasket and is configured to be used with closures formed of any number of materials, such as, e.g. metal, plastic, glass, etc. As in various embodiments the gasket may be incorporated into a coated closure, the gasket may also be configured to form a lasting bond with such closure coatings. In one embodiment, the closure may be pre-treated on its inner surface with a suitable primer, e.g. a TPE lacquer or other suitable primer coating (applied, e.g. by lamination, lining, co-extrusion, etc.).

As closures according to the various embodiments disclosed herein are commonly used to seal containers containing food and beverage components, it is preferable that the gasket-forming material used to form gaskets used with these closures do not include any substances that may present a risk to health. For example, the gasket-forming material should be free from any substance classified as presenting a health risk, including, but not limited to: plasticizers, phthalates; semicarbazide, ADC, OBSH; 2-ethylhexanoic acid and sources thereof, organic tin compounds, primary aromatic amines, bisphenols, nonylphenol; BADGE; photoinitiators; perhalogenated compounds, melamine, etc.

Additionally, the gasket may preferably be formed of a gasket-forming material configured to minimize or prevent migration of any of the gasket components into the container contents so as to avoid health risks and comply various regulations and standards related to migration of components into container contents. In one embodiment, the gasket is configured so that no more than 60 ppm, and preferably significantly less than 60 ppm of migrating components are detectable in the container contents.

In embodiments where the gasket is used for sealing food or beverage containing containers, the gasket may be configured to resist hot-filling at up to 100° C. for up to 60 min, starting from a hot-filling of at least 60° C. at a maximum of 10 min and a minimum of 1 min. The hot-filling starting from 60° C. can be accomplished in 60 min to up to 100° C. in increments of 5° C. In some embodiments, the gasket may be configured to withstand pasteurization (up to 98° C.) or sterilization (generally above 100° C., often above 105° C. or above 110° C., or even above 120°, up to 132° C.) without losing any desired sealing, vacuum retention, barrier, or other desired properties.

In some embodiments, a gasket may be formed from a gasket-forming material using out-shell molding in which the gasket-forming material is stamped and formed into a desired gasket outside of the closure. The gasket may subsequently be inserted into and applied to the closure. In such embodiments, the gasket may be optionally heated prior to insertion into the closure to effectuate better adherence of the gasket to the closure.

In other embodiments, the gasket may be formed in situ in a closure. In such embodiments, the gasket-forming material is applied to the inside of the closure in a thermally-induced flowable form, typically at a temperature ranging between 100° C. and 260° C.

In one embodiment, the gasket-forming material may be applied to the outer periphery of the closure in a ring shape in the area which will later abut the lip portion of a container using, e.g. a circular arrangement of application nozzles. Once the gasket-forming material has been applied in the desired ring-shape and at the desired location, the material may subsequently be fixed to the closure using, e.g. a stamping or any other appropriate fixating step.

In other in situ application embodiments, an extrusion of the gasket-forming material may instead be deposited into the middle of closure. Once deposited, the extruded gasket-forming material is stamped to form the gasket.

The options for providing a closure with a gasket may be limited by the type and/or features of the closure to which a gasket is to be incorporated. For example, certain closures may comprise structure(s) that cover or otherwise block access to the region of the closure to which a gasket is to be applied/on which the gasket is to be formed.

Lugged closures, such as, e.g. closures as described herein, are one example of a type of closure for which the application of a gasket may be problematic. Specifically, the radially inwardly extending lugs of such closures may block access to the portion of the closure top panel which will overlie the rim of the container to which the closure will be applied. As a result, a gasket-forming process utilizing injection nozzles to deposit a gasket-forming material in a ring-shape around an outer periphery of the closure may not be suitable for use with a lugged closure, as the lugs may block and prevent the nozzles from being able to deposit the gasket-forming material in the required locations along the closure surface.

In order to avoid gasket application issues caused by lugs blocking access to the closure top panel, in some embodiments the closure may be provided with a gasket prior to the lugs of the closure being formed. In such embodiments, where access to the outer periphery of the top panel of the closure is not impeded, the gasket may be provided using out-shell or in situ methods as described above, or any other known technique. Once the gasket has been applied, the closure skirt is shaped to from the desired lug structures. However, such an option may not be suitable in many situations. Specifically, in various situations, the gasket/gasket-forming material may be applied at a different processing location than that at which the closure is formed. As such, forming the closure skirt into the desired lug structure may not be feasible, as the requisite tooling for forming the lugs may not be readily available at the location at which gaskets are applied to the closures.

However, even in situations in which it would be possible to form the lugs subsequent to the incorporation of a gasket to the closure, such a process would be more time-consuming, inefficient, and costly than a process in which finished closures (i.e. in which lugs are formed) are provided with gaskets.

Accordingly, in one embodiment, a method of providing a lugged closure with a gasket may include extruding a gasket-forming material into a central portion of the closure. The gasket-forming material must be sufficiently flowable such that it may flow outwards towards the outer periphery of the closure. In closure embodiments having a circumferentially extending channel close to an outer periphery of the closure, the gasket-forming material may flow into and fill the channel.

Once the sufficiently flowable gasket-forming material has spread across the desired portions of the closure, a stamp generally having a diameter equal to or slightly less than a diameter defined by the radially innermost portion of the lugs may be used to press the gasket-forming material further into shape and to effectuate attachment of the gasket to the closure.

As noted above, a gasket as described above may be incorporated into and used with any number of closure types and sizes. In particular, in some embodiments it may be desirable to provide any of the closure embodiments and/or container assemblies as described herein (such as, e.g. the metallic lug/plastic container assembly discussed above) with a gasket having properties and qualities as discussed above.

More specifically, in certain embodiment, it may be desired to provide any of the large diameter (i.e. having a diameter greater than 20 mm), lugged closures as described herein with a gasket formed of a gasket-forming material that, among other properties:

- provides desired sealing and opening properties under various conditions;
- can be used with food or beverage products, including oily or fatty products;
- can be used and withstand non-room temperatures (e.g. warmer temperatures used during processing of contents and/or colder temperatures used during storage) without the desired gasket properties being negatively impacted; and
- has processing and application properties that allow the gasket material to be easily, quickly and cost-efficiently applied to a closure, including large diameter closures having various interior configurations, such as, e.g. radially inwardly extending lugs.

Conventional gasket-forming materials are not suitable for providing large diameter closures such as those describe herein with a gasket having the desired properties and meeting the various requirements as discussed above.

One of the obstacles to providing large diameter closures such as the closures discussed herein with a gasket having properties as discussed above relates to the flowability and composition of currently available gasket-forming materials. Specifically, because of the large surface area and relatively large quantity of gasket-forming material associated with forming a gasket in situ for large diameter closures such as those described, the gasket-forming material must be able to soften thermally to a sufficient extent so as to be fluid enough be applied to a closure. At the same time, the gasket-forming material must also retain the necessary sealing properties to provide the desired tightness and sealing to the container assembly, even after introduction into the closure and cooling to the desired application temperature.

In conventional compositions, this desired combination of flowability and sealing properties is typically accomplished through the inclusion of extenders (commonly oils, such as white oil, which are typically liquid at application and/or room temperature) and/or plasticizers (e.g. PVC-based materials) into the composition. Although the inclusion of such extenders and/or plasticizers may provide these conventional compositions with the desired fluidity and sealing properties, their inclusion is typically undesirable, particularly when the gaskets are used in container assemblies for storing food or beverage products.

Specifically, plasticizers such as PVC pose health risks, and accordingly in many embodiments the use of such components is entirely to be avoided. With regards to extenders, such as e.g. white oils, although such components in and of themselves are not harmful, their incorporation into gasket-forming materials may results in undesirable effects. For example, the incorporation of white oils or other components that are liquid at room and/or application temperatures may result in the unwanted migration of the gasket-forming material elements into the container contents, particularly when such gasket-forming materials are used in sealing containers containing fat- and oil-containing food and beverages.

On the other hand, cconventional oil- and PVC-free gasket-forming materials currently available are too hard and too inelastic, and show too high opening values to provide a gasket having the desired properties as discussed above.

Accordingly, described herein are various gasket-forming materials that are configured to form gaskets that can be used with the large diameter closures described herein and which avoid the problems associated with the use of conventional compositions in making such gaskets.

As discussed below, the composition of the gasket-forming material may vary between different embodiments, depending on the particular desired application and/or conditions in which a gasket formed from the gasket-forming material may be used (e.g. use under sterilization temperatures, cold temperature storage, use with fatty foods, desired scavenging and/or barrier properties, etc.). However, it is to be understood that while certain characteristics of the gasket/gasket-forming material may vary between embodiments, gaskets/gasket-forming materials according to each of the embodiments will preferably have the same or substantially the same physical characteristics (e.g. hardness, opening value, stress-loss, resiliency, etc.) and abilities to meet the generally desired properties related to, e.g. sealing, opening values, migration, processability, ability to be used with various shaped and size closures, etc. as described above.

In general, gasket-forming materials according to various embodiments comprise at least one polymer as a main component. In some embodiments, this main polymeric component may comprise a polyalkylene, or olefin block copolymer, comprising PE and an alkene monomer (e.g. propene, butene, hexene and, in particular, octene). In some embodiment, such an olefin block copolymer may be formed by using metallocene catalysts. In some embodiments, e.g. for gaskets used with oily or fatty foods, a gasket-forming material based on such polyalkylenes may be desirable, as such olefin block copolymers may be processed without requiring the using of extenders.

In some embodiments, e.g. when the gasket-forming material comprises a ‘hard’ polymer such as SEBS, the gasket-forming material may include a fluid extender and/or lubricant to improve the processability and/or twist-off properties of the gasket-forming material. However, for reason as explained above, in various embodiments the gasket-forming material is preferably formed with minimal or no components which are liquid at room temperature, such as, e.g. oils or other extenders and/or lubricants. In some embodiments, it is preferred that no more than 10% of the gasket-forming material is comprised of a component that is liquid at room temperature. In some embodiments, particularly when the gasket-forming material is to be used with oily or fatty foods, the gasket-forming material preferably contains no amount of ingredients which are liquid at application or room temperature.

Optionally, in various embodiments the gasket-forming materials may contain pigments, preferably inorganic pigments, in order to exclude a pigment migration. Other additives such as waxes, silicones and especially blowing agents may also optionally be added to the polymer compound, for example, in order to improve processing and performance characteristics.

In general, gaskets formed from gasket-forming materials as disclosed herein have a Shore A hardness between 40 and 95, preferably 45 to 90, and more preferably between 50 and 85.

Additionally, the gasket generally should be formed for as to have sufficient resiliency such that, following periods of prolonged compressive stresses (e.g. while the gasket is used to seal a closed container) at a given temperature and mount of deflection, the gasket is capable of returning to its original thickness once the gasket has been removed from the compressive environment (e.g. following opening of the container). Gaskets that exhibit a significant amount of loss of resiliency, permanent deformation, after being subject to compressive stresses may reduce the gaskets ability to provide a reliable seal over time.

The resiliency of the gasket may be tested by measuring the permanent deformation of the gasket according to a procedure in which a specimen of the gasket is compressed between parallel plates by a distance equal to approximately 25% of the original, unstressed thickness (i.e. height) of the specimen. The specimen is held in the compressed state between these plates for a period of twenty-two (22) hours at a temperature of 158° F., and subsequently is allowed to cool for 30 minutes. Following cooling the final height of the specimen is measured. The permanent deformation (defined in %) of the gasket is then measured as equal to: (original, unstressed height of the specimen−final height of the specimen)/(25% of the original, unstressed height of the specimen).

In some embodiments, the gasket may be formed of a gasket-forming material having a permanent deformation calculated as described of between 20% and 95% and more specifically between 30% and 70%. For sterilized products, the permanent deformation may be at higher values, up to 90%. For pasteurizable (but not sterilizable) products, the permanent deformation may be at somewhat lower values, up to about 80%. For compounds with thermoplastic vulcanizates (TPV materials), the lower limit of the permanent deformation may be down to 30%.

Gasket-forming material compositions according to various embodiments may include:

Example 1

Ethylene-octene block copolymer
37%-41%

(e.g. Infuse D9007)

Ethylene-octene random
58%-62%

copolymer (e.g. Engage 8402)

Antioxidant (e.g. Irganox 1010)
0.1%-0.3%

Stabilizer (e.g. Irgafos 168)
0.0%-0.2%

Lubricant (e.g. erucic acid amide)
0.2%-0.4%

Lubricant (e.g. oleamide)
0.2%-0.4%

Example 2

A thermoplastic elastomer based on SEBS, with
24%-28%

a fixed styrene content of 31%

White oil
33%-37%

LLDPE polyethylene (e.g. SABIC 118N)
16%-20%.

Polyolefin (e.g. ADFLEX C 200 F)
6%-10%

LDPE polyethylene (e.g. LDPE MFI 2)
10%-14%

Lubricants comprising erucic acid amide (e.g.
0.4%-0.6%

Finawax E)

Pigments (e.g. titanium dioxide)
0.2%-0.4%

Antioxidants (e.g. IRGANOX 1010)
0%-0.2%

Stabilizers (e.g. IRGAFOS 168)
0%-0.2%

Example 3

Polyolefin, preferably linear low-density
40-50
kg

polyethylene (e.g. by SABIC)

Styrene-ethylene/butylene-styrene block
15-25
kg

copolymer (e.g. Kraton G series)

Polyolefin, preferably
5-10
kg

polyethylene/polypropylene copolymer

(e.g. ADFLEX series)

Medicinal white oil (viscosity 70 cSt)
20-30
kg

Erucic acid amide (Kemamide E)
0.25-0.5
kg

Oleic acid amide (ARMOSLIP CPA)
0.25-0.5
kg

Antioxidant (IRGANOX 1010)
0.05-0.15
kg

Stabilizer (IRGAFOS 168)
0.05-0.15
kg

Pigment
0.2-0.7
kg

Example 4

Ethylene-octene copolymer
45%

EVA (14% VA)
40%

Highly flowable PP
14%

Stabilizers (Irganox 1010, Irgafos 168)
0.2%

Lubricant (erucic acid amide)
0.2%

Lubricant (oleic acid amide)
0.2%

Pigment
0.4%

Example 5

Polyolefin
8%

LDPE polyethylene
12%

Erucic acid amide
0.5%

Antioxidant
0.1%

Stabilizer
0.1%

SEBS (fixed styrene content 31%)
26%

White oil viscosity 70
35%

LLDPE polyethylene
18%

As noted above, is various embodiments, container assemblies comprising a gasket are configured to undergo various heat treatments, including hot-filling and pasteurization. In one embodiment, gasket-forming material composition that may be used for hot-filling and pasteurization may comprise:

Example 6

Ethylene-octene block copolymer
39.1%

Ethylene-octene random copolymer
60%

Antioxidant
0.2%

Stabilizer
0.1%

Lubricant
0.6%

However, in some embodiment, pasteurization of the contents may not be sufficient, requiring the food or beverages contents to instead be sterilized once the container has been filled and closed. Accordingly, in some embodiments it may be desirable that the gasket be configured to withstand the higher temperatures of sterilization treatments (generally above 100° C., often above 105° C. or above 110° C., or even above 120°, up to 132° C.) in addition to being configured to withstand the relatively lower temperatures the gasket may be subject to during hot-filling and pasteurization. A gasket formed from the gasket-forming material should preferably be configured to withstand sterilization without losing any desired sealing, vacuum retention, or barrier properties. In meeting all these characteristics, the gasket should also comply with the above-mentioned requirements regarding the migration of chemical constituents.

In some embodiments, a gasket configured for use with a container assembly that will undergo a high temperature sterilization process may be formed of a gasket-forming material mixture comprising at least three different plastics. In such embodiments, the gasket-forming material may optionally also include: additional plastics, one or more liquid components, one or more lubricants, one or more stabilizers, one or more pigments, and/or one or more fillers.

In some embodiments of a gasket-forming material formed of at least three polymers, at least one plastic is a substantially non-resilient, thermoplastic polymer. The other plastics are preferably resilient thermoplastic polymers and/or thermoplastic elastomers. The polymers may be block copolymers, polymer alloys, homopolymers etc. One or more of the plastics may be a mixture (e.g. a polymer blend, a polymer alloy, etc.). In some embodiments (and in particular in embodiments in which the gasket-forming material comprises between 0% and 10% PP), the gasket-forming material comprises no compounds in which the main polymeric component comprises 39-40% of ethylene octene block copolymer and/or 45-60% of ethylene octene random copolymer.

As will be understood by one skilled in the art, the selection of the three plastics can be varied depending on, among other considerations: desired permanent deformation characteristics, Shore A hardness, glass transition temperature, etc. of the gasket. In one embodiment, among the three plastics selected, the non-resilient thermoplastic selected will have (a) the lowest minimum temperature at which plastic deformation is possible; (b) the highest glass transition temperature; the highest Shore A hardness; the greatest modulus of elasticity; and the highest permanent deformation characteristics (as measured at 22 h and 70° C.) of the three plastics, while the thermoplastic elastomer will have: (a) the highest minimum temperature at which plastic deformation is possible; (b) the lowest glass transition temperature; the lowest Shore A hardness; the lowest modulus of elasticity; and the lowest permanent deformation characteristics (as measured at 22 h and 70° C.) of the three plastics.

Examples of non-resilient thermoplastics that may be used in the gasket-forming material include catalyzed polypropylene, such as, e.g. Metocene HM, and/or other polyolefins, e.g. PE or LDPE, etc.

Examples of thermoplastic elastomers that may be used in the gasket-forming material include SEBS (e.g. Taipol, Kraton, etc.), propylene-based elastomers, terpolymers, olefin based copolymers (e.g. Infuse), etc.

The resilient thermoplastic can comprise a block copolymer and/or elastomer alloy. Examples of resilient thermoplastics that may be used in the gasket-forming material include polymers offering a balanced compromise between an elastomer and a thermoplastic, such as, e.g. polyolefin elastomers including, e.g. Engage, Vistamaxx, etc.

As will be understood by one skilled in the art, the proportions by weight of the three plastics selected for the gasket-forming material can vary depending on use and/or the desired characteristics of the gasket. In one embodiment, the proportion by weight of non-resilient thermoplastic polymer is approximately 0% by weight to 80% by weight, preferably from 10% by weight to 70% by weight, and most preferably from approximately 10% by weight to approximately 50% by weight of the total weight of the gasket-forming material.

In one embodiment, the proportion by weight of the thermoplastic elastomer typically lies in a range from above 0% by weight to almost 100% by weight, preferably from 10% by weight to 50% by weight, and most preferably from approximately 20% by weight to approximately 35% by weight, in relation to the total weight of the gasket-forming material.

In one embodiment, the proportion by weight of the resilient thermoplastic polymer typically lies in a range from 10% by weight to 50% by weight, preferably from 15% by weight to 40% by weight, and most preferably from approximately 20′% by weight to approximately 40% by weight, in relation to the total weight of the gasket-forming material.

One embodiment of a gasket-forming material formed of three plastics as described above and configured for providing a pasteurizable gasket useable at counter pressure up to 98° C. and useable without counter pressure up to a maximum of 105° C., which can be used fatty products, and which has a Shore A hardness of 78 and a permanent deformation at 22 h/170° C. of 59 may comprise:

Example 7

polypropylene
10% by weight

olefin block copolymer
48.8% by weight

polyolefin elastomer
40% by weight

lubricant
0.6% by weight

stabilizer
0.3% by weight

pigment
0.3% by weight

One embodiment of a gasket-forming material formed of three plastics as described above and configured for providing a sterilizable gasket which can be used with fatty products, and which has a Shore A hardness of 78 and a permanent deformation at 22 h/170° C. of 69 may comprise:

Example 8

polypropylene
26% by weight

SEBS
27% by weight

polyolefin elastomer
38% by weight

Adhesion promoter (e.g. polyester)
8% by weight

lubricant
0.5% by weight

stabilizer
0.2% by weight

pigment
0.3% by weight

Another embodiment of a gasket-forming material formed of three plastics as described above and configured for providing a sterilizable gasket which can be used fatty products, and which has a Shore A hardness of 90 may comprise:

Example 9

polypropylene
35% by weight

olefin block copolymer +
44% by weight

SEBS

polyolefin elastomer
20% by weight

lubricant
0.5% by weight

stabilizer
0.5% by weight

In some embodiments, a gasket-forming material configured to form gaskets that can withstand high temperatures pasteurization and sterilization processes, such as described above, may be formed without a resilient thermoplastic polymer. Instead, in such embodiments, the gasket-forming material may instead contain a component that is liquid at application temperature (typically room temperature), such as, e.g. an oil extender. Such sealing compounds often contain significant quantities of oil, up to more than 50% by weight, but preferably between 5% by weight and 50% by weight and particularly preferably between 35% by weight and 50% by weight. White oil (with suitable viscosity, for example viscosity 70) is the most preferred oil component.

In such embodiments of a gasket-forming material formed without a resilient thermoplastic polymer, the gasket-forming material preferably contains at least 5% by weight of a thermoplastic elastomer, preferably based on styrene, Examples of such styrene-based block copolymers include, but are not limited to SBS, SEBS, SIBS, etc. In one embodiment, the gasket-forming material contains at least 5% by weight of a styrene ethylene butylene styrene block copolymer (SEBS) and a minimum content of 10% of a polyolefin polymer, such as PP or HDPE, even when mixed with LDPE and/or LLDPE.

One embodiment of a gasket-forming material formed of only two plastics and configured for providing a pasteurizable and/or sterilizable gasket, preferably for use with container assemblies in which the gasket does not come into contact with any fat-containing contents, and having a Shore A hardness of 68 and a permanent deformation at 22 h/70° C. of 27 may comprise:

Example 10

polypropylene + LDPE
25% by weight

SEBS
33% by weight

white oil
40% by weight

lubricant
1% by weight

stabilizer
1% by weight

Typically, gaskets formed from a gasket-forming material comprising a single plastic are not suitable for being used to seal containers that will undergo high temperatures during, e.g. pasteurization and/or sterilization procedures. Gasket-forming materials comprising a non-elastomeric thermoplastic (e.g. a PP polymer) as the only plastic are too hard and are not resilient enough. In contrast, gasket-forming materials comprising thermoplastic elastomer as the only plastic are too soft. However, in one embodiment, a gasket-forming material comprising a poly(ethylene-co-propylene)-based compound, and no other plastic may be processed with minor amounts of a conventional lubricant, to form a gasket formed a single plastic containing gasket-forming material that is configured for use under sterilization temperatures.

In some embodiments, the gasket may be configured to seal containers filled with oxygen-sensitive contents, including any number of oxygen-sensitive food and/or beverage products. In such embodiments, in addition to the generally desired gasket-forming material properties (related, e.g. to processability, sealability, migration, etc. as described above), it may also be desired that the gasket be configured to protect the container contents from oxygen in order to keep the contents unchanged in terms of taste and composition for as long as possible.

Accordingly, in some embodiments, the gasket-forming material may include a scavenging substance such as ascorbic acid, metal sulfites, etc. to protect the contents of the container from the effects of oxygen and/or other pollutants. In some embodiments, gasket-forming materials having scavenging properties comprise between 1% to 10%, and preferably between 4% and 8% of sodium sulfite. The average particle size of the sodium sulfite is adjusted to smaller than 20 μm, preferably smaller than 12 μm and particularly preferably smaller than 7 μm. Other components of such gasket-forming materials may comprise:

- between 2 and 20%, more preferably between 5% to 15% of a copolymer consisting of polypropylene (PP) and polyethylene (PE);
- between 5% to 25%, and more preferably between 10% to 20% of LDPE;
- between 10% to 40%, and more preferably between 20% to 30% of a thermoplastic elastomer based on styrene-ethylene-butylene-styrene (SEBS);
- between 20% to 45%, and preferably between 30% to 40% of oil (e.g. medicinal white oil);
- not more than 10%, preferably not more than 7%, more preferably not more than 4% and even more preferably not more than 1% of a lubricant;
- between 10% to 30%, and more preferably between 15% to 25% of LLDPE; and
- between 20% to 100% of a block copolymer, such as, e.g. an interpolymer of ethylene and at least one C₃-C₂₀alpha-olefin, or a copolymer of ethylene and one C₃-C₂₀alpha-olefin or of ethylene and one C₃-C₂₀alpha-olefin in case in combination with other unsaturated monomers.

A gasket formed of a gasket-forming material comprising an oxygen-depleting component or scavenger as descried above may not be suitable for use in all desired applications. Specifically, in some embodiments the incorporation of a scavenger additive is not sufficient to provide the desired degree of protection of the container contents from outside pollutants. Although the incorporation of a scavenger in the gasket may render harmless any unintended pollutants that may pass through the gasket (such as, e.g. oxygen), the scavenger is not configured to limit or prevent any pollutants from passing through the gasket. For example, in some embodiments, it may be preferred instead for the gasket to provide a barrier property to limit or prevent any pollutants from the ingress of oxygen and other volatiles (e.g. trichloroanisol and other volatile organic carbon compounds) into the container.

Accordingly, in some embodiments it may be desired to provide a gasket configured to provide enhanced barrier properties. In yet other embodiment it may be preferred to provide a gasket having both oxygen-depleting/scavenging properties as well as barrier properties so as to provide an enhanced degree of protection of the contents of the container from the effects of pollutants. Such a gasket having both scavenging and improved barrier properties may be provided by incorporating both scavenger particles (e.g. sodium sulfite ascorbic acid, etc.), as well as barrier-enhancing materials into the gasket-forming material.

In some embodiments, the composition of the gasket-forming material may be chosen such that the non-scavenger particle components of the gasket-forming material have a synergistic effect with the scavenger particles that are added to the gasket-forming material, imparting onto the incorporated scavenger particles a higher capacity to absorb water, and thereby enhancing the activation of the scavenger particles. Accordingly, in such embodiment a lesser amount of scavenger materials may be required to be added to the gasket-forming material to provide the gasket with the desired scavenging effect, which may not only reduced cost, but may also allow for easier and more flexible processing.

According to one embodiment, a gasket-forming material configured to provide both barrier and scavenging properties may be formed only from a thermoplastic polymer having a suitable hardness (e.g. HDPE) and a butyl rubber, wherein the only other components of the gasket-forming material comprise a scavenger and conventional additives (e.g. pigments, antioxidants, etc.). However, gaskets formed according to such embodiments are relatively hard and inflexible, and are accordingly most suitable for less demanding applications, e.g. for disposable bottles.

One example of a composition according to such an embodiment and having a Shore D hardness of 50 may comprise:

Example 11

Butyl rubber
23 wt.-%

HDPE
68.5 wt.-%

sodium sulfite
8 wt.-%

Erucamide, pigment
0.5 wt.-%

In embodiments in which a gasket having enhanced barrier and scavenging properties is to be incorporated in reusable and re-closable containers which may have uneven and rough edges to the container mouth, it may be desirable to provide softer and more flexible gaskets. Accordingly, in some embodiments the gasket-forming material may contain softening polymers in addition to the mixture of the hard polymer and butyl rubber to provide for a softer and more elastic gasket having improved sealing even when the gasket is used in the repeated sealing of uneven, rough and damaged container mouths.

Optionally, such embodiments may also include, among other components ethylene-octene (block) copolymers, LDPE, EVA, and soft-elastic polypropylene copolymers, etc.

In such embodiments, the gasket-forming material may comprise a non-cross linked (rubbery) barrier polymer such as, e.g. butyl rubber, polyisoprene, polyisobutylene, SIBS, or polybutene.

Also included in the gasket-forming material of such embodiments as a ‘softening polymer’ may be one or more thermoplastic polymers. In some embodiments, the incorporated thermoplastic polymer may comprise a polyolefin. Specifically, in some embodiments the polyolefin may be based on PE and may comprise various combinations of one or more types of PE, e.g. HDPE and LPPE, HDPE and LLDPE, HDPE and LLDPE and LDPE, etc. Alternatively, or additionally the thermoplastic polymer may include PP and/or a copolymer of propylene and ethylene (co-PP).

In these embodiments, the relative total content of the thermoplastic polymer is preferably higher than that of the non-cross linked (rubbery) barrier polymer. In some embodiments, the relative content of the non-cross linked (rubbery) barrier polymer, e.g. SIBS, is above 5% by weight, more preferably is between 10% 30% by weight of the gasket-forming material.

The relative total content of thermoplastic polymer, e.g. polyolefin, is generally at least 30% by weight, preferably at least 50 wt % and optionally at least 70% by weight. Gasket-forming materials formed according to such embodiments typically have a Shore D hardness between 30 and 60, e.g. between 45 and 55.

Similar to the scavenger-containing embodiments of gasket-forming materials previously described, in embodiments of gasket-forming materials configured to impart both enhanced scavenging and barrier properties, the scavenger compound incorporated into the gasket-forming material may comprise between 1 to 10%, and preferably 4 to 8% by weight of sodium sulfite.

In various embodiments, the gasket-forming material may additionally comprise:

- up to 25%, more preferably up to 20% and most preferably between 5% and 15% of a block copolymer, such as e.g. an interpolymer of ethylene with at least one C₃-C₁₀-alpha-olefin or a copolymer of ethylene with a C₃-C₂₀alpha-olefin optionally in combination with other unsaturated monomers;
- an ethylene vinyl acetate (EVA), preferably having a VA content of between 1% to 30%, and preferably between 5% and 25% (particularly if the gasket-forming material also incorporates an ethylene-octene block copolymer);
- less than 10%, more especially less than 5%, and most preferably no oil and also no other constituents that are liquid at room temperature;
- up to 80%, more preferably up to 70%, and most preferably between 40% to 50% of HDPE
- between 5% to 25%, and preferably between 10% to 15% of LDPE; and
- up to 30%, preferably up to 10%, and more preferably up to 5% of LLDPE.

In addition to providing enhanced barrier and scavenging properties, the gasket-forming materials according to the described embodiments are also configured to withstand a hot filling of up to 100° C. for up to 60 min, starting from a hot-filling of at least 60° C. in at most 10 min and at least 1 min. The hot filling, starting from 60° C., can be carried out at in 60 minutes in increments of 5° to up 100° C.

Examples of various gasket-forming material compositions configured to provide enhanced barrier and scavenging properties may include:

Example 12

Butyl rubber
20 wt.-%

HDPE
55 wt.-%

Ethylene-octene block copolymer,
10.5 wt.-%

EVA (19% VA)
6 wt.-%

sodium sulfite
8 wt.-%

Erucamide, pigment
0.5 wt.-%

Shore D-hardness
45

Example 13

Butyl rubber
17.5 wt.-%

HDPE
54 wt.-%

Ethylene-octene block copolymer,
10 wt.-%

EVA (14% VA)
10 wt.-%

sodium sulfite
8 wt.-%

Erucamide, pigment
0.5 wt %

Shore D-hardness
44

Example 14

Butyl rubber
15 wt.-%

HDPE
51 wt.-%

Ethylene-octene block copolymer,
15 wt.-%

EVA (14% VA)
10.5 wt.-%

sodium sulfite
8 wt.-%

Erucamide, pigment
0.5 wt.-%

Shore D-hardness
43

Example 15

Butyl rubber
20 wt.-%

HDPE
36 wt.-%

Ethylene-octene block copolymer,
15.5 wt.-%

LLDPE
20 wt.-%

sodium sulfite
8 wt.-%

Erucamide, pigment
0.5 wt.-%

Shore D-hardness
40

Example 16

Butyl rubber
18 wt.-%

HDPE
30 wt.-%

Ethylene-octene block copolymer,
15.5 wt.-%

LLPDE
20 wt.-%

EVA (14% VA)
8 wt.-%

sodium sulfite
8 wt.-%

Erucamide, Pigment
0.5 wt.-%

Shore D-hardness
39

Example 17

HDPE
30 wt.-%

Ethylene-octene copolymer
15.5 wt.-%

LDPE
36 wt.-%

LLDPE
10 wt.-%

sodium sulfite
8 wt.-%

Erucamide, pigment
0.5 wt.-%

Shore D-hardness
40

Where a gasket is only required to have enhanced barrier properties (i.e. scavenging properties are not needed), it is to be understood that any of the above listed exemplary compositions of Examples 12-17 may be modified by omitting the scavenger material from the composition of the gasket-forming material.

In some embodiments, the composition of the gasket-forming material may be such that the gasket-forming material may provide both barrier properties and scavenging properties without requiring the addition of a scavenger material (i.e. the inclusion of the scavenger material is optional). Exemplary embodiments (wherein HDPE 1 is an HDPE have a melt-flow index at 190° C. and 5 kg of 30 and HDPE 2 is an HPDE having a melt-flow index at 190° C. and 5 kg of 2) of such compositions include:

Example 18

Butyl rubber
25 wt %

HDPE 1
50 wt %

HDPE 2
24.5 wt %

Erucamide, pigment
0.5 wt %

Shore D-hardness
50

Example 19

SIBS
25%
wt %

HDPE 1
50%
wt %

HDPE 2
4.5
wt %

erucamide, pigment
0.5
wt %

Shore D hardness
50

Example 2

SIBS
17.5
wt %

HDPE 1
37.5
wt.-%

HDPE 2
24.5
wt %

LDPE
20
wt %

Erucamide, pigment
0.5
wt %

Shore D hardness
49

Example 21

Butyl rubber
23 wt %

HDPE 1
46.5 wt %

HDPE 2
22 wt %

Na₂SO₃
8 wt %

Erucamide, pigment
0.5 wt %

Shore D hardness
50

Example 22

SIBS
23
wt %

HDPE 1
46.5
wt.-%

HDPE 2
22
wt %

Na₂SO₃
8
wt %

Erucamide, pigment
0.5
wt %

Shore D hardness
50

Example 23

SIBS
15.5
wt %

HDPE 1
35
wt.-%

HDPE 2
22
wt.-%

LDPE
19
wt %

Na₂SO₃
8
wt %

Erucamide, pigment
0.5
wt %

Shore D hardness
49

In some embodiments, a container assembly comprising a gasket may be used to store food or beverages that are filled at cold, room temperature, or hot-fill temperatures, and which may subsequently be stored at temperatures at or below room temperature (such as, e.g. refrigerated items). Such contents may include any number of fatty, low-fat, or fat-free food or beverage items, including, e.g. yogurt, cheese in oil (e.g. feta), fish in oil (e.g. sardines); jams; mayonnaise, etc.

In addition to having the generally desired properties as described above related to, e.g. processability, sealability, migration, etc., in embodiments where the filled container is stored at temperatures at or below room temperature, and in particular where the container assembly is stored in cold (e.g. refrigerated) environments, the gasket-forming material may be configured to also provide for a gasket that allows for easy opening of the container (i.e. have a sufficiently low twist-off value) and provides vacuum retention even at such low temperatures.

In embodiments in which the container that will be stored at temperatures at or below room temperature contains low-fat or fat-free product and/or if the contents being stored at temperatures at or below room temperature will be initially subject to pasteurization or sterilization temperatures, the gasket-forming material may be based on a styrenic block copolymer. In one embodiment, the styrenic block copolymer may comprise a SEBS mixed with a polyolefin having a Shore D hardness above 65. The gasket-forming material may also comprise a polyolefin having a Shore D hardness below 60 and/or oil so as to provide the gasket with the required softness, opening value, and sliding properties for use with container assemblies that are to be stored at temperatures at or below room temperature.

In embodiments in which the container that will be stored at temperatures at or below room temperature contains low-fat or fat-free products but the container assembly is not subject to pasteurization or sterilization temperatures, the gasket-forming material may be based on a styrenic block copolymer mixed with polyolefins, In such embodiments, the gasket-forming material may contain between 20% to 50%, and preferably between approximately 30% to approximately 40% by weight of a styrenic block copolymer.

The styrenic block copolymer may comprise a SEBS, preferably one having a high molecular weight and high absorbency for oil. The styrenic block copolymer may alternatively (or additionally) comprise thermoplastic elastomer components, such as Kraton G grades with a linear structure and a polystyrene content of about 30-35%.

In embodiments in which the container that will be stored at temperatures at or below room temperature contains low-fat or fat-free products but the container assembly is not subject to pasteurization or sterilization temperatures, the gasket-forming material may also comprise a ‘hard’ polyolefin, (such as, e.g. a propylene homopolymer with a Shore D hardness above 65 and preferably of about 70) in an amount between 5% and 30%, and preferably in an amount between approximately 8% and approximately 15% of the total weight of the gasket-forming material.

The gasket-forming material may also comprise a ‘soft’ polyolefin, such as, e.g. LLDPE with a Shore D hardness of about 50. Relevant contents of LDPE are preferably avoided. The content of ‘soft’ polyolefin is generally between 10% and 30%, and preferably between 8 and 20%. In some embodiments, oil such as, e.g. medical white oil may also be included in the gasket-forming material, with the oil content being between 5% and 50%, and more particularly between 30% and 50% by weight.

A gasket-forming material suitable for forming a gasket for a container containing low-fat or non-fat foods stored at temperatures between approximately 0° C. and room temperature, according to one embodiment, may have a Shore A hardness of 73 at 20° C. and 80 at 4° C., and a permanent deformation measured according to ISO 815 of 13% and room temperature and 35% at 4° C., and may comprise:

Example 24

SEBS
33%

Homo-PP
10.5%

LLDPE
15%

White oil
40%

Pigment
0.3%

Fatty acid amide
1%

Stabilizer
0.2%

In embodiments in which the container stored at temperatures at or below room temperature contains a fatty product, the gasket-forming material may be based on a styrenic block copolymer mixed with an ethylene-octene copolymer, e.g. a random copolymer. The ethylene-octene copolymer is preferably a random copolymer, e.g. Engage, and may be present in an amount of between 10% and 80%, and more preferably between 20% and 60%, and specifically between 20% and 35% of the total weight of the gasket-forming material.

The styrenic block copolymer may consist of SEBS, such as, e.g. Kraton G. In one embodiment, the styrenic block copolymer may comprise a polystyrene content of 11.5%-13.5% and have a Shore A hardness of about 35. The styrenic block copolymer may be present between 5% and 70%, and more particularly between 10% and 30% by weight of the gasket-forming material. In embodiments having a high content of SEBS (i.e. 25% or more), the gasket-forming material can be reacted with harder polyolefin such as, e.g. LDPE. In such embodiment, the content of lubricant is preferably low, e.g. 1% or less.

In some embodiments, the gasket-forming material to be used for gaskets that will be used with fatty content may also comprise a thermoplastic polyolefin, such as, e.g. PP elastomers (such as, e.g. Vistamaxx), ethylene-octene block copolymers, etc. The thermoplastic polyolefin content may be between 10 to 50%, and preferably 30 to 45%. If the gasket-forming material contains a thermoplastic polyolefin, a hard polyolefin, e.g. propylene homopolymer, is also provided in an amount between 0 and 30%, and more preferably between 15 and 25%.

In embodiments not incorporating a thermoplastic polyolefin, the gasket-forming material preferably contains substantial proportions of ethylene-octene block copolymer, e.g. Infuse. The ethylene-octene block copolymer content is broadly between 10% and 80%, more particularly between 20% and 60%, and preferably between 40% and 50%.

For gaskets used in non-pasteurized/non-sterilized fatty-content containing container assemblies stored at temperatures at or below room temperature, the gasket-forming material preferably contains less than 5% oil, and more preferably is oil-free. When polyolefin elastomers are used, the content of lubricants (fatty acid amides) is generally higher.

A gasket-forming material suitable for forming a gasket for a container containing a fatty substance stored at temperatures between approximately 0° C. and room temperature and having a Shore A hardness of 78 at 20° C. and 85 at 4° C., and a permanent deformation measured according to ISO 815 of 32% and room temperature and 47% at 4° C., according to one embodiment, may comprise:

Example 25

SEBS
24%

PP elastomer
40.3%

Homo-PP
18%

Random copolymer
12.5%

Pigment
0.3%

Lubricant
4%

Stabilizer
0.2%

A gasket-forming material suitable for forming a gasket for a container containing a fatty substance stored at temperatures between approximately 0° C. and room temperature and having a Shore A hardness of 68 at 20° C. and 72 at 4° C., and a permanent deformation (measured according to ISO 815) of 13% and room temperature and 28% at 4° C., according to one embodiment, may comprise:

Example 26

SEBS
25%

Random copolymer
28%

Block copolymer
45.5%

Lubricant
1%

Pigment, stabilizer
0.5%

Further modifications and alternative embodiments of various aspects of the invention will be apparent to those skilled in the art in view of this description. Accordingly, this description is to be construed as illustrative only. The construction and arrangements of the closure, as shown in the various exemplary embodiments, are illustrative only. Although only a few embodiments have been described in detail in this disclosure, many modifications are possible (e.g., variations in sizes, dimensions, structures, shapes and proportions of the various elements, values of parameters, mounting arrangements, use of materials, colors, orientations, etc.) without materially departing from the novel teachings and advantages of the subject matter described herein. Some elements shown as integrally formed may be constructed of multiple parts or elements, the position of elements may be reversed or otherwise varied, and the nature or number of discrete elements or positions may be altered or varied. Other substitutions, modifications, changes and omissions may also be made in the design, operating conditions and arrangement of the various exemplary embodiments without departing from the scope of the present invention.

CLOSURE WITH GASKET

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