Patent Application
20130209000
This invention relates to an easy-open and reclosable package with a die-cut web and a reclosure mechanism, and to methods of making the package.
Food and non-food products, including produce, snack foods, cheese and the like have long been packaged in containers such as pouches, bags, or lidded trays or formed webs made from various thermoplastic materials such as polyethylene, polypropylene, or polyester (PET). These containers can be formed from a web or webs of thermoplastic material on packaging equipment, using various packaging processes, at a processing/packaging facility. Such equipment and processes includes horizontal form/fill/seal (HFFS), vertical form/fill/seal (VFFS), thermoforming/lidstock, and continuous horizontal packaging (sometimes referred to as Flow-wrap). In each case, the product is manually or automatically placed in a pouch, bag, formed web, tray, etc., the filled container is optionally vacuumized or gas flushed, and the mouth of the container is hermetically or non-hermetically sealed to close and finish the package.
Opening of the finished package (i.e. opening with the use of tools such as scissors or knives) can provide access to the product by the consumer.
Common in the industry is the use of pressure sensitive adhesive to provide a reclosability feature to a package. However, based on the position of the adhesive relative to the package, the adhesive can sometimes be contaminated by the contained product before the package is opened, or once the package is opened, when product is removed from the package and comes in contact with the adhesive. This phenomenon can compromise the reclosability of the package. Also, the performance of the adhesive can sometimes be compromised at refrigerated conditions, or in the presence of grease or moisture caused by the packaging of greasy or wet foods.
Also common in the industry is the use of plastic zipper closures; press-to-close or slide zippers, interlocking closures; reclosable fasteners with interlockable fastener elements; and interlocking rib and groove elements having male and female profiles; interlocking alternating hook-shaped closure members, and hook and loop fasteners; fasteners employing self-engageable male fastener elements; fasteners utilizing interference fit, and the like. These features provide reclosability, and in some cases may provide an easy-open feature to the package.
There is need in the marketplace for a package, and methods of packaging involving e.g. an HFFS, VFFS, thermoforming/lidstock, or continuous horizontal packaging process, that can be used in a manner that requires little or no modification to the packager's packaging equipment, while providing a manually (i.e. by hand, without the need for tools such as scissors or knives) openable and easy to reclose feature, optionally while maintaining hermeticity of the package when made, and optionally without the use of pressure sensitive adhesive and the like.
The present invention relates to a package, and methods of making the package, which package is manually openable and reclosable, i.e. can be opened and reclosed a number of times, and adapted to package non-food products; food products such as e.g. produce, snack foods, cheese, luncheon meat, sausage, culinary nuts, trail mix, etc; medical or pharmaceutical products; or other items that benefit from being packaged in an easyopen/reclosable package. The package optionally maintains a hermetic seal until the package is opened.
In a first aspect, an easy-open and reclosable package enclosing a product comprises:
In a second aspect, a method of making an easy-open and reclosable package in a horizontal form/fill/seal process comprises:
In a third aspect, a method of making an easy-open and reclosable package in a vertical form/fill/seal process comprises:
In a fourth aspect, a method of making an easy-open and reclosable package having a formed web comprises:
In a fifth aspect, a method of making an easy-open and reclosable package in a continuous horizontal packaging process comprises:
In a sixth aspect, a pouch comprises:
In a seventh aspect, a method of making a bag with a die cut and a reclosure mechanism disposed thereon comprises:
The present invention is illustrated by reference to the following drawing figures, encompassing different views of various embodiments of the invention, wherein:
“Anchored”, “anchoring” and the like herein refers to sealing or adhering two surfaces together, and refers to the resulting bond between surfaces. Sealing is done by means of a sealant. Adhering is done by means of PSA or permanent adhesive. In processes described herein where a strip is anchored to a web or side panel, either during a process wherein the web and strip are advanced, or when a strip has been pre-anchored to the web before the start of the process, anchoring can be done by use of any suitable continuous or discontinuous sealing or adhesive material and method. Such anchoring is done to hold the strip to the web during the relevant packaging process.
In some embodiments, wherein the anchor is already relatively strong or continuous, e.g. a heat seal that constitutes either a relatively strong heat seal, or an easy-open seal as defined herein, the anchor functions not only to hold a strip to a web during a packaging process, but also as a final seal of that surface of the strip to the web (lay-flat or folded) or panel made from the web. Any subsequent step in the process of sealing one of the surfaces (i.e. the anchored surface) of the strip to a web or panel, is in these embodiments already completed by the anchoring step, and contact of a seal device, e.g. a seal bar in the region of the anchor, in a subsequent step, may add no further or separate seal to that surface of the strip.
In some embodiments where the bond is a relatively weak or discontinuous one, e.g. a discontinuous seal, spots or narrow stripes of adhesive, etc., in a subsequent step of sealing one of the surfaces of the strip to the web or panel, a seal bar that seals one of the surfaces of the strip to the web or panel can contact the web or panel in the region where the anchor is already disposed. The seal in that region may be either enhanced, or initially created, by the subsequent sealing step.
Anchoring a strip to a surface, as described herein, should be understood as anchoring all, or at least a portion of, the strip to all, or at least a portion of, the surface.
“Closed-loop” herein refers to a die cut that defines a closed pattern or path in the first side panel whereby the web material within the path (the die-cut segment) can be displaced.
“Die cut” and the like herein refers to methods of cutting or scoring materials, including rotary die, steel rule die, platen die cutting, and laser cutting or scoring; and to the resulting cut or score. A die cut can extend entirely or partially through the relevant layer or web, and can in some embodiments leave intact a certain amount of material. “Score” and the like herein refers to a partial die cut that extends partly but not entirely through the thickness of a material, layer, web, panel, etc, The purpose of the score in the present invention is to provide for controlled tear or separation of material in the act of displacing the die cut segment. The depth of the cut can vary from package to package, and within a single die cut or die cut segment on a given package.
“Die-cut segment” herein refers to a portion of the first side panel that can be displaced because of the presence of a closed-loop or open-loop die cut. The die-cut segment is a piece of the first side panel, and when displaced can in some embodiments function as a tamper evidence device, and facilitates access to the interior of the package.
“Displaced” and the like herein refers e.g. to a die cut segment that has been at least partially moved from its original position, and in some embodiments entirely removed from the package, sufficient to open the package and provide access to its contents.
“Easy-open” herein refers to a package that can be manually opened relatively easily.
“Easy-open seal” herein refers to a seal involving two surfaces, in which materials and sealing conditions are chosen such that the package is easy-open with a physical mode of opening that includes any one or more of adhesive failure, delamination failure, or cohesive failure as described herein.
“Easy-open sealant” herein refers to a material chosen for one or both surfaces of an interlocking strip and web, such that when such surfaces are sealed to each other, the resulting package is easy-open with a physical mode of opening that includes any one or more of adhesive failure, delamination failure, or cohesive failure as described herein.
“Ethylene/alpha-olefin copolymer” (EAO) herein refers to copolymers of ethylene with one or more comonomers selected from C3 to C10 alpha-olefins such as propene, butene-1, hexene-1, octene-1, etc.
“Ethylene homopolymer or copolymer” herein refers to polyethylene (PE) such as ethylene homopolymer such as low density polyethylene (LDPE), medium density polyethylene (MOPE), high density polyethylene (HDPE); ethylene/alpha olefin copolymer such as those defined herein; ethylene/vinyl acetate copolymer (EVA); ethylene/alkyl acrylate copolymer such as ethylene/methyl acrylate copolymer (EMA) or ethylene/ethyl acrylate copolymer (EEA), or ethylene/butyl acrylate copolymer (EBA); ethylene/(meth)acrylic acid copolymer; or ionomer resin (IO).
“Exposed” herein means exposed to the exterior environment outside the package.
“Fig.” herein refers to drawing figure; “Figs.” to drawing figures.
“Film” is used herein to mean a thermoplastic film, laminate, or web, either multilayer or monolayer, that may be used in connection with the present invention. Film can be of any suitable thickness, e.g. between 0.1 and 30 mils.
“Fin seal” is used herein to mean, in the case of a single web, folding one edge of a web towards the opposite edge of the web, and sealing the facing inner surfaces together. In the case of two webs, a fin seal is a seal formed by sealing the inner surface of the edge of one web to the inner surface of a corresponding edge of another web.
“Interlocking strip” and the like is used herein to refer to a strip of material having an interlocking surface that can be mechanically engaged with (interlocked with) another interlocking strip, of the same or different construction, to provide a package that can be opened and reclosed a number of times. Examples of an interlocking strip include, without limitation, 1) zippers such as those associated with the ZIPLOC™ and ZIP-PAK trademarks, and disclosed in e.g. US2003/0103687 A1 (Schneider et al.), but excluding a slide zipper; 2) interlocking alternating hook-shaped closure members, and hook and loop fasteners such as those associated with the VELCRO™ trademark, and disclosed in e.g. US2006/0062496 A1 (Clune et al.); 3) fasteners employing self-engageable fastener elements such as those associated with the APLIX™ trademark, and disclosed in e.g. US 2010/0135600 A1 (Ducauchuis et al.) and U.S. Pat. No. 7,841,052 B2 (Ducauchuis); and 4) fasteners utilizing interference fit, e.g. as shown in U.S. Pat. No. 3,727,829 (Huni); all these US patent publications and patents incorporated by reference in their entirety. An “interlocking surface” herein will typically be three-dimensional. It will be understood that in many embodiments of the invention, only a portion of the interlocking surface of each of the respective interlocking strips will be exposed when the die cut segment is displaced, e.g. because of the presence of side seals that will prevent edge portions of the respective interlocking surfaces from being exposed. Likewise, in many embodiments of the invention, when the package is reclosed, only a portion of the exposed respective interlocking surfaces will be interlocked with one another, e.g. because of differences in the manner in which the user recloses the package.
“Lap seal” is used herein to mean a seal made by sealing an inside surface of a web to an outside surface of a web. The inside and outside surfaces can both be on a single web; or the inside surface can be of one web, and the outside surface of a second web.
“Lidstock” herein refers to a film used to cover a container or tray that carries a product, and can be sealed to the tray, typically as a perimeter heat seal. Lidstock typically is supplied to a food processor in a lay flat film rolled onto a roll.
“Longitudinal seal” herein refers to a fin seal or lap seal.
“Olefinic” and the like herein refers to a polymer or copolymer derived at least in part from an olefinic monomer.
“Open-loop” herein refers to a die cut that defines an open pattern or path in the first side panel whereby the web material within the path or pattern (the die-cut segment) can be displaced from its original position on the panel, e.g. by acting as a flap.
“Oxygen barrier” and the like herein refers to materials having an oxygen permeability, of the barrier material, less than 500 cm3 O2/m2·day·atmosphere (tested at 1 mil thick and at 25° C., 0% RH according to ASTM D3985), such as less than 100, less than 50, less than 25, less than 10, less than 5, and less than 1 cm3 O2/m2·day·atmosphere. Examples of polymeric materials useful as oxygen barrier materials are ethylene/vinyl alcohol copolymer (EVOH), polyvinylidene dichloride (PVDC), vinylidene chloride/methyl acrylate copolymer, vinylidene chloride/vinyl chloride copolymer, polyamide (nylon), and polyester (PET).
“Polymer” and the like herein means a homopolymer, but also a copolymer thereof, including terpolymer, tetrapolymer, block copolymer, etc.
“Pouch” herein means a pouch or bag.
“Pre-anchored” herein means an embodiment wherein an interlocking strip has been anchored to a web before the start of the relevant process. For example, an interlocking strip can be anchored to a lay-flat web by a supplier of the web, and the rolled up web, with the interlocking strip anchored thereto, can then be supplied to a packager who uses the web and strip in any of the processes disclosed herein.
“Reclosable” herein refers to a feature or function of a package whereby a package can be reclosed by folding the package such that a first interlocking strip is brought into interlocking engagement with a second interlocking strip.
“Reclosure mechanism” herein refers to a first and second interlocking strip, each strip including a first and second side edge, a first and second end, and an interlocking segment having a base surface and an interlocking surface.
“Registration device” herein refers to any mark, pattern, die cut or feature of a web or interlocking strip, that facilitates the advancement of the web or strip, in a controlled manner, into a packaging machine, where the web or strip is used to make individual packages. The device can be e.g. printed, as for example an eye-spot, or placed in uniformly spaced fashion along or near an edge of the web or strip, i.e. registration marks, or in an area near the middle of a web that does not interfere with decorative printed graphics. These marks are used in connection with appropriate sensors to controllably advance the web or strip. Where die cuts are used as a registration device, detected by sensors, it may not be necessary to print registration marks on the web or strip.
“Seal” herein means a bond between two thermoplastic surfaces, e.g. as produced by heat sealing, radio frequency (RF) sealing, ultrasonic sealing, permanent adhesive, or repositionable adhesive or PSA, or a combination of any of these modes of sealing. Sealing a strip to a surface, as described herein, should be understood as sealing all, or at least a portion of, the strip to all, or at least a portion of, the surface.
“Sealant” is a polymeric material or blend of materials, such as olefinic polymer or copolymer such as an ethylenic polymer or copolymer, that can form a surface of an interlocking strip, or a web to which the strip is sealed, and form a bond between two thermoplastic surfaces. A permanent or a repositionable adhesive such as pressure sensitive adhesive can also be a sealant.
“Shadowed” and the like herein refers to a die cut segment that is at least partially underlain by an interlocking strip, i.e. when the die cut segment is displaced, at least a part of the interlocking surface of the interlocking strip is exposed at the opening in the first side panel created by displacing the die cut segment.
“Strip” herein refers to an elongate piece of thermoplastic material, typically longer in a first direction than in a direction perpendicular to the first direction, e.g. rectangular; but can also be square, round, oblong, elliptical, or any appropriate shape in plan view. The strip can be of any suitable thickness, e.g. between 0.1 and 30 mils.
“Tamper evidence”, “tampering”, and the like herein refers to visual evidence of a breach in a package; i.e. that someone has accidentally or intentionally opened or partially opened the package, or attempted to do so.
“Thermoplastic” herein includes plastic materials that when heated to a softening or melting point may be reshaped without significant thermal degradation (burning). Thermoplastic includes both materials that are not crosslinked, or that are crosslinked by chemical or radiation means.
“Tray” herein refers to a formed member that has a tray bottom, tray sides, and a tray flange around the upper perimeter of the tray, where the tray bottom and tray sides form an internal cavity within which a product can be placed. The cavity can be enclosed by a lidstock sealed to the tray flange.
“Web” is used herein to mean a thermoplastic film, laminate, or web, either multilayer or monolayer, that may be used in connection with the present invention. The web can be of any suitable thickness, e.g. between 0.1 and 30 mils, and the web can be of any suitable length and width.
“Zipper” and the like herein refers to a plastic zipper closure, press-to-close or slide zipper, interlocking closure, reclosable fastener with interlockable fastener elements, interlocking rib and groove elements having male and female profiles, interlocking alternating hook-shaped closure, and the like.
All compositional percentages used herein are presented on a “by weight” basis, unless designated otherwise.
Drawings herein are not necessarily to scale, and certain features of the invention may be graphically exaggerated for clarity.
1. Package
Referring to the drawings, a package 5 according to the invention is shown. Package 5 includes a pouch 7 that can be made from either a single web, or two webs, to form a first or front side panel 12, and a second or back side panel 14.
A. Web(s)
In either embodiment, the web or webs (hereinafter “web”) comprises a thermoplastic material of any suitable composition, e.g. those having as at least one component olefinic materials such as ethylene or propylene polymers or copolymers, e.g. polyethylene or ethylene/alpha olefin copolymers; or polyethylene terephthalate (PET). A suitable web includes those typically used in, or useful in, HFFS, VFFS, lidstock/tray, continuous horizontal packaging, and bag making apparatus and processes. The web can be monolayer or multilayer in construction, can be coextruded, laminated, or made by any suitable film making process, and can have any suitable thickness. Examples of a web useful in the invention include H7225B™, a barrier hybrid material used for products requiring a high oxygen barrier, such as shredded cheese; H7525B™, a barrier hybrid material used for products requiring a high oxygen barrier, such as bacon and smoked and processed meat; H7530B, like H7525B but having a thickness of about 3 mils; CP04140™, a low barrier (high OTR) material used in produce packaging, CPM4090, a microwaveable packaging film for fresh cut produce; and T7225Bυ, a barrier material used as lidstock for products requiring a high oxygen barrier, such as luncheon meat. These are all commercial products produced by the Cryovac business unit of Sealed Air Corporation. In some embodiments, for example in the packaging of produce, the web will typically not have an oxygen barrier layer.
Referring to the drawings, the first side panel 12 has a top portion 9, a first side edge 31 and second side edge 33, and a lower portion 17. The second side panel 14 has a top portion 11, a first and second side edge (not shown), and a lower portion 18. In a finished package, the first and second side edges 31 and 33 of first side panel 12 will typically be congruent with the first and second side edges of second side panel 14. The first and second side panels 12 and 14 are joined together along their respective first and second side edges by either a seal or a fold. First side edge 31 of first side panel 12 is joined to the first side edge of the second side panel 14 by a seal 30. Second side edge 33 of first side panel 12 is joined to the second side edge of the second side panel 14 by a heat seal 32. The second end 34 of the pouch 7 can be either a seal or a fold. Where a single web is used to make the pouch, second end 34 will typically be a fold, although even after the web is folded, a seal such as a heat seal can optionally be installed in the area of the fold. Where two webs of film are used to make panels 12 and 14, second end 34 will be a seal that joins panels 12 and 14 together along their respective lower portions 17 and 18. The two webs can be from the same material, or can be different in composition, structure, etc.
B. Interlocking Strips
Referring to
Interlocking strip 10 can optionally include a first skirt segment denoted by region SL, and/or a second skirt segment denoted by region SR. These skirt segments may be useful in the manufacture of strip 10, and may also be useful in anchoring strip 10 to a web. Skirt segment SL is shown with a base portion 263, a base surface 253 and a second surface 254. Skirt segment SR is shown with a base portion 265, a base surface 255 and a second surface 256. Strip 10 can alternatively include additional or alternative skirt segments such that interlocking segment “D” is bounded on some or all of its sides by a skirt segment.
Second interlocking strip 13 can be configured like first interlocking strip 10, or can be of any suitable alternative construction, provided it can be brought in interlocking engagement with strip 10 to reclose the package after the package has been initially opened.
Both interlocking strips 10 and 13, and their analogs disclosed in the present application, are disposed between first panel 12 and second panel 14. Typically strips 10 and 13 are spaced apart from the first and second ends of the pouch, but strip 10 is disposed farther from the first end of the pouch than strip 13. In one embodiment, strip 13 is disposed at the first end of the pouch. Typically, strips 10 and 13 are parallel to one another, and spaced apart from each other sufficiently to enable the package, after opening, to be folded at a fold region disposed between the strips, such that the interlocking surface of second strip 13 can be brought into engagement with the interlocking surface of first strip 10 to reclose the package.
Strips 10 and 13 can be of any suitable dimension, and will typically be longer in length than in width, with the length of the strip 10 being e.g. greater than two times the width of the strip, e.g. greater than 3, 4, or 5 times the width. A typical dimension for the strips is a width of from about 0.25 inches to 1.5 inches and a length of about 7 inches. The strips will be shorter in at least one dimension than the pouch and package. For example, the strips can extend across the transverse width of a pouch made in a HFFS or VFFS process, but will be significantly narrower than the length of the package (see e.g.
One or more of the surfaces of strips 10 and 13 comprise a sealant. In one embodiment, the second surface 254 of skirt segment SL of strip 10 is anchored to the inner surface 27 of the first side panel 12, and surfaces 251, 253 and/or 255 of strip 13 are anchored to the inner surface 29 of the second side panel 14. In this arrangement, optionally the second surface 256 of skirt segment SR is sealed to the inner surface 27 of the first side panel 12 with an easy open seal. In some embodiments, the first and second strips 10 and 13 are sealed to the inner surfaces 27 and 29 of first and second side panels 12,14 respectively only along the first and second side edges of the package. In other embodiments, the strips are sealed to the respective inner surfaces of the package along a portion of, or along the entire width of the package.
When a product 24 is placed in the pouch 7, by processes herein disclosed, and the pouch 7 is closed, the package 5 is made.
Opening Mechanisms
The package of the invention can be easily manually opened, by displacing the die cut segment 56 as described herein. In some embodiments, where an easy-open supplemental seal is additionally present, any suitable mechanism or combination of mechanisms for obtaining this functionality and feature can be used according to the invention. One mechanism is adhesive failure, where two surfaces each comprises a polymeric composition that, when the surfaces are sealed together, form an easy-open seal. This seal provides the interface that breaks apart upon manually opening the package. In some embodiments, the polymeric compositions of the two sealed surfaces will be the same or similar. In other embodiments, the compositions of the two surfaces will differ, i.e. dissimilar sealants are used. Another mechanism is delamination failure, where the interlaminar bonds between layers of a material, such as a multilayer film, can be broken. Thus, the interlaminar bond provides the interface that will break apart upon manually opening the package. Yet another mechanism is cohesive failure, where a layer of a material such as a film fractures when the package is opened.
Optionally, especially for applications where hermeticity of the package is required before the package is first opened, an easy-open supplemental seal, of any suitable geometry, can be used to seal the inner surface of the first side panel to the end of strip 10 closest to the first end of the package; to the second strip 13; or to the inner surface of the second side panel (see e.g. easy-open supplemental seal 38 of
In some embodiments, a first portion of the die cut segment has a score, and a second portion of the die cut has a through cut.
Referring to
The invention is characterized by the fact that:
2. Method of Making a Package
A. Horizontal Form/Fill/Seal (HFFS)
HFFS packaging systems are generally well known to those of skill in the packaging industry, and can be used to make packages of the present invention.
Referring to
Interlocking strip 310, equivalent to strip 10 of
Interlocking strip 313, equivalent to strip 13 of
Optionally, strips 310 and 313 can be tacked by a discontinuous seal, adhesive, or the like to web 300 to keep the strips in place during the HFFS packaging process. Alternatively, they can be permanently anchored to the web, and/or any easy-open supplemental seal as described herein, can be installed at this point or later in the process, e.g. by a suitable sealing mechanism such as a heat sealer (not shown).
Strips 310 and 313 are thus installed on the pouch in the same overall HFFS process that achieves production of the pouch, loading of a product into the pouch, and completion of the package. Strips 310 and 313 are incorporated into the pouch and after cutting and sealing as described herein, are disposed between and anchored to the inner surfaces of the first and second side panels respectively of each package, such that the interlocking surface of each of strips 310 and 313 faces the inner surface of the first side panel.
In the embodiment of
In alternative embodiments, strips 313 and 310 can be disposed on the web in any suitable arrangement. For example, the strips can be fed onto web 300 such that strip 313 is near and spaced apart from the end fold 306 of each pouch, i.e. near and above the end fold at the bottom of each pouch. Strip 310 can be disposed such that in the final pouch, strip 310 is further from end fold 306 than strip 313. Die cuts on the web are suitably arranged such that the opening mechanism disclosed herein can be used in these alternative embodiments to open the package, by removal of a die cut segment, and expose at least a portion of the interlocking surfaces of the first and second interlocking strips.
Alternatively (
B. Vertical Form/Fill/Seal (VFFS)
Apparatus 40 utilizes a lay-flat web 41 as a rollstock. Web 41 includes die cuts made in a predetermined pattern (see e.g.
Interlocking strips 84 and 54 (
Pouches 49 and 50, and subsequent pouches, each comprise a first and second side panel, and in each pouch, strip 84 is anchored to the inner surface of the first side panel, and strip 54 is anchored to the inner surface of the second side panel. Strips 84 and 54 are thus trapped between the inner surfaces of the first and second side panels respectively, arranged so that the interlocking surfaces of each of strips 84 and 54 face the inner surface of the first side panel.
Alternatively (
In some embodiments, at least one of the web and strips carries a registration device.
In
Alternatively (
At any time during the method of making the package in an HFFS or VFFS process, strips 310 and 313, 84 and 54, or comparable pairs of strips, are anchored to the lay-flat web, the folded web, or the inner surface of the first side panel. This can be done e.g. on the lay-flat web prior to supplying the web to the processor, prior to or as the lay-flat web is advanced to a forming device, or before or after a product is put in the open pouch.
C. Lidstock/Formed Web
Pak, is used to convert flat thermoplastic forming web into formed pockets to create trays for containing product such as food, various industrial and consumer items and sterile medical products. Trays are formed from a lower web by heat and pressure, loaded with product manually or automatically, optionally vacuumized or backflushed with modified atmosphere, hermetically sealed to an upper web, separated, and removed for distribution or storage. Alternatively, pre-made trays can be used, that can be rigid or semi-rigid, flat or shaped, and made from any suitable material, solid or expanded, including PP, polystyrene, polyamide, 1,4-polymethylpentene (e.g. TPX™ available from Mitsui), or crystallized polyethylene terephthalate (CPET). A tray liner can optionally be used that adheres to the surface of the pre-made tray on which the product is to be placed. This liner can be of any suitable design, and can be a multi-layer structure with at least one layer with gas-barrier properties. Such a liner can be adhered to the tray by heat lamination, extrusion lamination, extrusion coating, adhesives, corona treatment, etc. Tray 602 can be a flexible or semi-rigid, or rigid formed web.
Tray 602 has a tray bottom 604, tray sides 606, and a tray flange 608 along its perimeter to which the lidstock 612 can be sealed by heat or other means. Tray bottom 604 and tray sides 606 define a tray cavity. Tray 602 can be of any suitable thickness, e.g. from 2 to 30 mils thick, and any suitable construction.
Referring to
Strip 610 is disposed on the inside surface of the lidstock, anchored to the inside surface of the lidstock, and oriented such that its interlocking surface 252 (see
To open the package, die cut segment 56 is removed by grasping the tab shown at one end of the die cut segment in
Lidstock 612 can be sealed and cut, e.g. perimeter heat sealed and cut, in registered fashion by otherwise conventional means, e.g. in thermoforming equipment, as the lidstock 612 is advanced from a roll into a packaging system where it is progressively fed over filled trays, sealed to the trays, and cut to create finished packages.
Strip 610 can be anchored to lidstock 612 by the supplier of the lidstock, as in the embodiments of
Strip 613 can be anchored to a web to be made into the formed web by the supplier of the web, as in the embodiments of
As strips 610 and 613 are disposed respectively on a lidstock, or a web to be formed into a formed web, they can be brought into contact with, and optionally tacked or anchored to a surface of the relevant web as in the HFFS and VFFS embodiments disclosed herein.
D. Continuous Horizontal Packaging
In another embodiment, and referring to
Web 702 and interlocking strip 724 can be of any suitable dimension and composition, such as those disclosed herein. As strip 724 is fed to forming device 710, it can be brought into contact with, and optionally tacked or anchored to a surface of web 702, as in the HFFS and VFFS embodiments disclosed herein.
Strip 722 is oriented such that its interlocking surface 252 faces web 702. Strip 724 is oriented such that its base surface 251 faces web 702. The strips are arranged in a finished package such that the strips are trapped between inner surfaces of web 41, and are not exposed to the exterior of the package before initial opening of the package.
E. Side Seal Bags
In one embodiment (
Side seal bag 180 includes web 182, first edge 184 defining an open mouth, edge fold 190, first side seal 192, and second side seal 194. Interlocking strips 189 and 191 are anchored on a bag, or on a slit bag tubing that is then cut and sealed at predetermined intervals to make a series of side seal bags 180, by any suitable process such as any of those disclosed herein. Each bag includes a first side panel and a second side panel, and interlocking strips 189 and 191 are trapped between the first and second side panels of the bag. Both strip 189 and strip 191 are oriented such that their respective interlocking surfaces 252 face the inner surface of the first side panel. Strip 189 is anchored to the inner surface of the first side panel, and strip 191 is anchored to the inner surface of the second side panel. Strips 189 and 191 can be brought into contact with, and optionally tacked or anchored to a relevant surface of the bag tubing, slit bag tubing, or bag at any suitable time during the manufacture of the bag.
A bag with a die cut and interlocking strips disposed thereon can be made by extruding a thermoplastic tube to make a bag tubing; die cutting the bag tubing at predetermined intervals; slitting the tubing at one longitudinal edge thereof; and periodically transversely cutting and sealing the bag tubing to make a plurality of individual bags each with two interlocking strips disposed thereon. Strips 189 and 191, and the die cut can function as described herein for other embodiments and processes, in providing an easy-open and reclosable package. Some of the steps set out in US 2008/0138478 A1, for making a bag, are optional with respect to the present invention; e.g. irradiation and orientation of the tubing.
Method of Operation
In opening a package in accordance with the invention, (
To reclose the package, a portion of the second side panel can be folded over, e.g. at fold region FR, such that interlocking strip 13 comes into interlocking engagement with interlocking strip 10.
The package can thereafter be reopened and reclosed several times.
Method of Making a Die Cut in a Web
A conventional die cutter can be used to create die cut 21, and optionally one or more additional die cuts in a web used to make first side panel 12. Die cuts can be made by any suitable conventional process and equipment. Any suitable pattern of die cut can be used, open or closed-loop, as long as it serves the function of providing an easy-open package in which the packaged product can be accessed by means of displacement of a die cut segment defined at least in part by the die cut. Alternative patterns include elliptical, oval, triangular, rectangular, hour glass, “dog bone”, and other regular and irregular shapes.
The die cut can extend completely through the first side panel, or may extend through most of, but not entirely through, the thickness of the panel. The die cut may extend through e.g. at least 50% of the thickness of the first side panel, e.g. at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, or 100% of the thickness of first side panel 12. The die cut can extend at different thicknesses through a single side panel, whether open or closedlooped.
A laser system can be configured to produce a laser cut that cuts partly or completely through the panel, or alternatively, a die cut can be made using a mechanical cutting system using rotary engraved dies, or steel rule dies supported in platens as used in reciprocating presses. The choice of die cutting technique depends on several factors, including the thickness and physical nature of the film or web to be cut.
The die cut may act as a tamper evident feature.
The application of interlocking strips, the die cutting of a web to produce a first side panel, and the assembling of a package incorporated a die cut web and the interlocking strips, can be done at a single location, or at separate locations, with the assembling of the package by a packager using pre-provided interlocking strips and a die cut web prepared elsewhere and provided in advance of the packaging process.
A package is made in accordance with the embodiment illustrated in
First and second side panels 12 and 14 respectively each comprise H7530B, a laminate having the construction:
where the PET is a biaxially oriented polyester film, and the coextruded barrier film has the construction:
The overall thickness of the coextruded barrier film is about 2.50 mils. Layer gauges in mils for each layer are indicated below each layer. Layer 7 is the layer of the barrier film adhered, by the adhesive, to the PET film. Layer 1 is the heat sealant layer of the film, and the EAO (PE1) of layer 1 forms the inner or sealant surface of the package, facing the contained product, and the PET forms the outer or skin surface of the package. The thickness of the PET film is about 0.48 mils. The overall thickness of the laminate is about 3.0 mils.
Alternatives to the composition of layer 7 include various combinations of materials, including:
The interlocking strips 10 and 13 of the package are in this example strips having self-mating micro-hooks derived from the EASY-LOCK™ closure system available from Aplix Inc.
Before the package is made, strips 10 and 13 are anchored to the H7530B web (specifically, to layer 1 of the coextruded barrier film of the H7530B laminate) while the latter is in a lay-flat condition (see
The above descriptions are those of embodiments of the invention. Although this disclosure has been directed primarily at embodiments wherein the second interlocking strip is anchored to the inner surface of the second side panel (or, in the aspect of the formed web and lidstock, anchored to the inner surface of the formed web), those skilled in the art will appreciate that for any of the disclosed aspects and embodiments of the invention, the second interlocking strip can in a first alternative be anchored to the inner surface of the first side panel (or, in the aspect of the formed web and lidstock, anchored to the inner surface of the lidstock). In a second alternative, the second interlocking strip can be anchored to the inner surface of both the first and second side panel (or, in the aspect of the formed web and lidstock, anchored to the inner surface of both the formed web and the lidstock).
One advantage of the first alternative is that anchoring of both the first and second strips to the first side panel may be easier than anchoring the first strip to the first side panel, and the second strip to the second side panel. One disadvantage is that the contents of the package could in some instances be trapped in the region between the second strip and the first end of the package. The second alternative would avoid this trapping issue, but may reduce to some extent the internal volume of the package available for holding product.
All parts and percentages are by weight, unless otherwise indicated or well understood in the art. Except in the claims and the specific examples, or where otherwise expressly indicated, all numerical quantities in this description indicating amounts of material, reaction conditions, use conditions, molecular weights, and/or number of carbon atoms, and the like, are to be understood as modified by the word “about” in describing the broadest scope of the invention. Any reference to an item in the disclosure or to an element in the claim in the singular using the articles “a,” “an,” “the,” or “said” is not to be construed as limiting the item or element to the singular unless expressly so stated. All references to ASTM tests are to the most recent, currently approved, and published version of the ASTM test identified, as of the priority filing date of this application. Each such published ASTM test method is incorporated herein in its entirety by reference.
Terms referring to polymers, such as polyester, polyamide, and polyolefin, refer herein to both homopolymers and copolymers thereof, unless otherwise specified.
In the drawings, the flow of materials is in the direction of the arrows.
The drawings herein are not necessarily to scale, and certain features of the invention may be graphically exaggerated for clarity.
Both the web or webs used in the manufacture of the package according to the invention, and the interlocking strips, can be made by any suitable process, including coextrusion, extrusion coating, extrusion lamination, and conventional lamination using polyurethane or other adhesives. Extrusion can be done in annular or flat dies. The extrudate can be hot blown or cast, and optionally solid-state oriented as desired. Chemical or electronic crosslinking of one or more layers of the webs can be done. Both web and strips can be advanced by suitable motive means (not shown, and well known in the art, such as a motor) from their respective rolls.
A package according to the invention can optionally carry printed indicia, which can be decorative or informational in nature. Decorative printed indicia can include a logo, a trademark, product information, etc. with text and/or graphics.
Printed indicia can be in the form of a message e.g. “easy open” or “open here”. This can be printed in scattered process (i.e. registration is not required) on or near the first end of the package, and surface printed or reverse printed.
In some embodiments, it may be beneficial to adhere the strips to the lay-flat web prior to processing on equipment, or at the time, before processing, when the strips are disposed on the web. Any suitable means, such as permanent adhesive or heat sealing, can be used to seal the strips to the web to ensure that the strips maintain their position on the web during processing. In some embodiments, the strips are anchored to the web at the interface between the web and the surface of the strips comprising a sealant layer that provides a relatively strong seal. The strips can be e.g. sealed to the web by a suitable device (not shown) such as a heat sealer, disposed below the web while the web is in its lay-flat condition.
In the embodiments disclosed herein, the first end of the package can be sealed, typically where two webs are used to make the package. Alternatively, the first end of the package can be a fold, e.g. where a single web of material is used to make the package.
Although the invention is described in some embodiments herein as a package comprising a pouch comprising a first and second side panel each having a top edge, a first side edge, and a second side edge, those skilled in the art will understand, after a review of this disclosure, that in some embodiments, wherein a single web is used, the terms “side panel”, “top edge”, “first side edge”, “second side edge”, and the like are used for convenience to describe the relative locations or regions on a single web made into a pouch, so that the overall geometry of the package, and relative positions of the various features of the invention can be described. Thus, for instance, the first and second panels in a single web embodiment of the invention can be simply defined regions of the pouch, and the package made therefrom, and side edges are simply the side lines of those regions. In such embodiments, the line of joinder of the side edges are the two side folds in the web that define the sides of the package. In contrast, in embodiments with two webs, each web when produced will have an identifiable first and second side edge, that will each be joined to a respective side edge of a second web.
Although the first and second side panels are shown in various embodiments as having the same length, the second side panel can in some embodiments be longer than the first side panel, i.e. the first end of the second side panel can extend beyond the first end of the first side panel, or vice versa. The extended portion can e.g. accommodate a hang tab with a hole therein, or function as a fold-over flap for reclosing the package after opening.
Those skilled in the art will appreciate that in describing a panel, strip or the like being “sealed” to another panel, strip, or the like, sealing is done by conventional means as described, and typically occurs in seal widths consistent with industry practice for packaging.
Packages of the various embodiments of the invention disclosed herein can optionally be vacuumized or gas flushed by otherwise conventional means. A package in accordance with the invention can contain a modified atmosphere.
For the avoidance of doubt, the present application is directed in various embodiments to the subject matter described in the following paragraphs. These are optional embodiments of any of the first, second, third, or any subsequent aspects of the invention as described hereinabove in the Summary of the Invention, and for each aspect these features can be taken alone or in any suitable combination of these features:
