The present invention relates generally to a method for texturing a film and more particularly for texturing a film to be fabricated into a fluid container.
Collapsible plastic bags are often used to store liquid products such as chemicals, soft drink syrup, fruit juices and food condiments. The plastic bags are typically housed in a corrugated paperboard box to aid in the transporting, handling and dispensing of the product. Such packaging systems are commonly referred to as “bag-in-box” packaging systems.
The plastic bags typically have sidewalls sealed along a peripheral seam to define a fluid containing chamber. A spout or a fitment provides access to the fluid chamber for filling and dispensing the product within the bag. Vacuum pump systems are sometimes connected to the container to assist in draining fluid from the container. Both gravity dispensing bags and vacuum pump systems suffer from the common drawback that fluid may become trapped within the folds of the bag during draining. Because of this, evacuation channels are often placed within the bag. Evacuation channels are typically elongate cylindrical tubes or flat strips with protruding ribs defining grooves. Typically, one end of the evacuation channel is disposed transverse to, or is connected to the spout, and the other end of the evacuation channel extends into the fluid containing chamber of the bag. As the bag is emptied by the force of the vacuum pump, or by the force of gravity, portions of the bag collapse unevenly, tending to leave pockets of product, typically liquid, which may become isolated from the rest of the liquid in the container. The evacuation channel, however, forms a conduit which cannot be closed off by the folds created in the bag. In this manner the entire chamber of the flexible bag remains in communication with the spout at all times during the dispensing such that all product within the bag can be removed.
Prior attempts to provide such bags are disclosed in U.S. Pat. Nos. 4,601,410; 5,647,511 and 5,749,493. U.S. Pat. Nos. 4,601,410 and 5,647,511 disclose a liquid container with an evacuation unit. In both the '410 and '511 patents, the evacuation unit is shown attached directly to the spout by a mounting ring. Several problems have been encountered with these types of evacuation units. For example, during the filling process, which is typically done in a high speed and high pressure process, the evacuation unit is susceptible of being dislodged from the spout thereby rendering the evacuation unit inoperative. Also, the attaching ring can impede the flow of liquid during the filling process thereby slowing the filling process.
U.S. Pat. No. 5,749,493 discloses an evacuation unit positioned within a bag and transverse and perpendicular to a spout in the bag. Because the evacuation unit is positioned in a location that is in line with the incoming fluid during the filling process, it is susceptible of being dislodged from its mounting to the container thereby rendering it ineffective. The '493 Patent also discloses extruding a pair of ribs or a single rib or protuberance extending the length of the container.
Many of the designs which utilize an evacuation unit positioned within the bag require that the unit be placed into the bag after the bag has been substantially constructed. This is undesirable because it adds another step to the manufacturing process and increases the labor costs.
U.S. Pat. No. Re. 34,929 discloses a plastic bag having interconnected air channels on its inner surface for the vacuum packaging of perishable items. The air channels are formed by the spaces between a plurality of raised protuberances having uniform thickness and formed in a generally regular and waffle-like pattern. The protuberances prevent the total collapse of the bag during air evacuation. There is no disclosure to utilize a fitment to provide access to the contents of the container. There is also no disclosure of removing the stored contents of the bag, but, rather only discloses moving air from the package to prevent spoilage of the perishable item contained therein.
U.S. Pat. No. 2,778,171 discloses the production of air-tight packages for packaging perishable items such as food. Projections are provided near an opening of the airtight package for keeping sidewalls of the container from fully collapsing against one another while air is being evacuated from the container. There is no disclosure of evacuating a stored product from the container and no disclosure of providing a fitment with the bag to provide access to the stored contents.
U.S. Pat. No. 5,728,086 discloses a flexible container having multiple access ports and particularly discloses a container for storing fluids for parenteral administration to a patient. An inner surface of a sidewall of the container can have various patterns embossed thereon to assist in draining the contents of the container.
U.S. Pat. No. 5,928,762 discloses a laminate of a base film and an embossed sheet and a method for fabricating the same. The method includes the steps of joining a base sheet to a molten sheet material. The molten sheet material is cooled and solidified using a cooling roll having embossing patterns in its surface. The method includes the steps of embossing the molten sheet and simultaneously laminating the molten sheet with the base sheet. In an alternative method, an adhesive resin is coextruded on the side of the molten sheet facing the base material. There is no disclosure in the '762 Patent of utilizing more than a single preformed sheet material to fabricate a layered polymeric structure.
The present invention provides a method for treating a surface of a layered polymeric structure. The method includes the steps of: (1) providing a first sheet of material, (2) providing a second sheet of material, (3) positioning the first sheet or the second sheet to overlap at least a portion of the other sheet to define an interference zone, (4) directing a first polymeric material into the interference zone to adhere the first sheet to the second sheet to form the layered structure; and (5) texturing a surface of the first sheet or the second sheet to form a pattern on the surface.
While this invention is susceptible of embodiment in many different forms, herein will be described in detail with the accompanying figures, a preferred embodiment of the invention. The present disclosure is to be considered as an exemplification of the principles of the invention and is not intended to limit the broad aspect of the invention to the embodiments illustrated and described.
The sidewalls can be formed from a monolayer film, a multiple layer film or can be formed of several individual sheets of such films joined together to define a multiple sheet sidewall.
Suitable polymeric materials for forming these films include polyolefins, ethylene and vinyl acetate copolymers, ethylene copolymerized with carboxylic acids having from 3 to 20 carbons and ester and anhydride derivatives thereof, ethylene and vinyl alcohol copolymers, polyamides, polyesters, polyvinyl vinyl chloride, PVDC and the like. The film can be formed by polymer processing techniques well known in the art including, but not limited to, extrusion, coextrusion, molding, blow molding, blown extrusion, lamination and the like. The films can also be treated by primers, ozonolysis, and can be metalized.
Suitable polyolefins include homopolymers such as polyethylene, polypropylene, polybutene, etc., and copolymers of ethylene and α-olefins where the α-olefins have from 3–20 carbons, and more preferably from 4 to 8 carbons. Suitable polyethylene homopolymers include those commonly referred to as low density polyethylene (LDPE). Suitable ethylene and α-olefin copolymers include, for example, ethylene butene copolymers, ethylene hexene copolymers and ethylene and octene copolymers. These copolymers are commonly referred to as linear low density polyethylene (LLDPE), very low density polyethylene (VLDPE) and ultra-low density polyethylene (ULDPE) and typically have a density of less than about 0.915 g/cc.
Suitable polyamides include polyamides formed from condensation reactions of diamines and dicarboxylic acids or ring opening reactions of caprolactams. In a preferred form of the invention the polyamides are selected from the group nylon 6,6, nylon 6, and nylon 6,12 and even more preferably is nylon 6.
The container 10 can be made from individual sheets of film placed in registration and sealed along the periphery 14 using standard sealing techniques well known in the art.
The objects 20 can form a regular pattern or an irregular pattern. The regular pattern includes objects being placed at the same or essentially the same spacing or a repeating sequence of spacings. The irregular pattern is one where the objects are generally randomly distributed.
In a preferred form of the invention as shown in
A plurality of sum objects 47 are shown connected together to define a web of interconnected sum objects 47. It is contemplated that the sum objects 47 could be positioned in other relationships and other patterns without departing from the scope of the invention. Of course it is also contemplated that any combination of shapes of protuberances can be used and that more than two different shapes can be used together to form patterns of various shapes and sizes.
The present invention further provides a process for evacuating the container shown in
In a preferred form of the invention the first sheet and the second sheet are polymeric films as described above. However, it is contemplated that the first sheet and/or the second sheet could be selected from paper or metal foil provided that one of the layers is capable of maintaining the pattern during regular use of the layered structure 66.
The first sheet 60 can be a monolayer structure or a multiple layered structure as set forth above. The monolayer structure can be of a polymer blend of the polymeric components. The multiple layered structure can have a layer or more than one layer of a polymer blend of the polymeric components. In one preferred form of the invention the first sheet is a film having a layer of a polyolefin and more preferably an ethylene and α-olefin copolymer, and even more preferably is an LLDPE. Such a first sheet having an LLDPE layer has been found to be well suited to form a seal layer or liquid contacting layer of a container 10 as LLDPE forms strong, durable seals.
In another preferred form of the invention, the first sheet 60 can also be a multiple layered polymeric structure having a first layer of a polyolefin and a second layer to provide additional attributes to the film such as scratch resistance, barrier to the transmission of gasses or water vapor or the like. Suitable materials to form a barrier material includes ethylene and vinyl alcohol copolymers, polyamides, polyesters, PVDC and metal foil to name a few. One preferred multiple layered film to form the first sheet 60 has a first layer of LLDPE and a second layer of ethylene vinyl alcohol copolymer.
The second sheet 62 is also preferably a monolayer polymeric film or a multiple layered polymeric film selected from the films and polymeric materials detailed above. In one preferred form of the invention, the second sheet 62 is a barrier material and more preferably a polyamide or polyester and even more preferably nylon 6. The first sheet 60 and the second sheet 62 can be preformed and provided on spooled rolls 68 or the sheets can be laminated or otherwise produced in line.
The step of positioning the first sheet 60 in an overlapping relationship with the second sheet 62 is accomplished using standard polymeric sheet handling machinery. In a preferred form of the invention either the first sheet 60 is positioned with respect to the second sheet 62, or the second sheet 62 is positioned with respect to the first sheet 60 or both sheets are positioned with respect to one another so that in any instance the peripheries of the first and second sheet are essentially in complete registration.
The step of directing the first polymeric material 65 into the interference zone 64 to adhere the first sheet 60 to the second sheet 62 to form the layered structure 66 can be carried out by flowing polymeric material in a molten form into the interference zone 64. Molten polymeric material can be provided under pressure to the interference zone 64 using an extrusion die 70. The polymeric material may be extruded as a single polymeric material or a blend of polymeric materials. The polymeric material may also have multiple layers coextruded from a coextrusion die. It is also contemplated to that the first polymeric material can be an adhesive that can be sprayed or otherwise spread or distributed into the interference zone 64. In a preferred form of the invention the first polymeric material is a polyolefin and more preferably an ethylene homopolymer and even more preferably a LDPE.
The step of texturing the film can include the step of imparting a desired pattern described above onto the first sheet 60 or the second sheet 62 or both. The step can be carried out prior to the step of joining the sheets together, substantially or essentially simultaneously with the step of adhering the first and second sheets together, as shown in
The step of texturing the film includes the step of bringing the sheet or layered structure to be textured into cooperative engagement with a surface having the desired pattern thereon. In a preferred form of the invention, the surface 71 is located on a roll and more preferably a chill roll 72. The chill roll 72 can be fabricated from any suitable material such as metal, plastic or cork. The chill roll 72 can have the pattern extending inward of its outer surface or can extend outward from its outer surface. The sheet or structure is held in cooperative engagement against the chill roll 72 using a back-up roll 74. The back-up roll 74 can be made from metal, rubber, plastic or paper and most preferably rubber. It should be understood that either the chill roll 72, the back-up roll 74 or both can carry the pattern.
After the layered structure 66 passes the chill roll it proceeds along to a spooling station or to be fabricated into useful objects like the container 10.
While the specific embodiments have been described, numerous modifications come to mind without significantly departing from the spirit of the invention and the scope of protection is only limited by the scope of the accompanying claims. This design is just one example of a pattern design having these favorable characteristics, and disclosure of it is merely one example of a design having its favorable characteristics, others of which are not significant departures from the spirit of the invention.
Number | Name | Date | Kind |
---|---|---|---|
336826 | Steeneken | Feb 1886 | A |
972095 | Booth | Oct 1910 | A |
1109110 | Clark | Sep 1914 | A |
1884215 | Edwards | Feb 1932 | A |
2024908 | Blum | Dec 1935 | A |
2027290 | Reach | Jan 1936 | A |
2106671 | Watson | Jan 1938 | A |
2116009 | Brown | May 1938 | A |
2133411 | Zohe | Oct 1938 | A |
2196708 | Reid | Apr 1940 | A |
2392594 | Karfiol et al. | Jan 1946 | A |
2477300 | Karfiol et al. | Jul 1949 | A |
2569975 | Cone | Oct 1951 | A |
2643027 | Fink | Jun 1953 | A |
2659516 | Smith | Nov 1953 | A |
2672268 | Bower | Mar 1954 | A |
2697635 | Ivins et al. | Dec 1954 | A |
2714557 | Mahaffy | Aug 1955 | A |
2731297 | Meyer | Jan 1956 | A |
2736468 | Hills | Feb 1956 | A |
2778171 | Taunton | Jan 1957 | A |
2778173 | Taunton | Jan 1957 | A |
2804257 | Hasler et al. | Aug 1957 | A |
2809800 | Ahl | Oct 1957 | A |
2859899 | Kramer et al. | Nov 1958 | A |
2862648 | Cooksley et al. | Dec 1958 | A |
2870954 | Kulesza | Jan 1959 | A |
2885084 | Rocca | May 1959 | A |
2891700 | Maynard | Jun 1959 | A |
2920798 | Samuel | Jan 1960 | A |
3063461 | Rudolph | Nov 1962 | A |
3081911 | Scholle | Mar 1963 | A |
3083875 | Welty et al. | Apr 1963 | A |
3090526 | Hamilton et al. | May 1963 | A |
3110754 | Witort et al. | Nov 1963 | A |
3112047 | Weinreich et al. | Nov 1963 | A |
3142599 | Chavannes | Jul 1964 | A |
3171571 | Daniels | Mar 1965 | A |
3176727 | Rousseau | Apr 1965 | A |
3197073 | Gondra et al. | Jul 1965 | A |
3203026 | Schwartzman | Aug 1965 | A |
3204825 | Underwood | Sep 1965 | A |
3212681 | Weikert | Oct 1965 | A |
3219240 | Campbell, Jr. | Nov 1965 | A |
3240399 | Frandeen | Mar 1966 | A |
3244576 | Swartz | Apr 1966 | A |
3254828 | Lerner | Jun 1966 | A |
3257036 | Micallef | Jun 1966 | A |
3260412 | Larkin | Jul 1966 | A |
3334659 | Magorien | Aug 1967 | A |
3342377 | Peredy | Sep 1967 | A |
3361303 | Jacuzzi | Jan 1968 | A |
3366284 | Marona | Jan 1968 | A |
3367380 | Dickey | Feb 1968 | A |
3411698 | Reynolds | Nov 1968 | A |
3420413 | Corsette | Jan 1969 | A |
3456850 | Uhlmann | Jul 1969 | A |
3469796 | Guenther | Sep 1969 | A |
3549050 | Bruce et al. | Dec 1970 | A |
3587794 | Mattel | Jun 1971 | A |
3666182 | Cureton | May 1972 | A |
3695314 | Watts et al. | Oct 1972 | A |
3718236 | Reyner et al. | Feb 1973 | A |
3799914 | Schmit | Mar 1974 | A |
3809217 | Harrison | May 1974 | A |
3838794 | Cogley et al. | Oct 1974 | A |
3881519 | Zahid | May 1975 | A |
3902516 | Rudolph | Sep 1975 | A |
3946780 | Sellers | Mar 1976 | A |
3958693 | Greene | May 1976 | A |
3981415 | Fowler et al. | Sep 1976 | A |
3988499 | Reynolds | Oct 1976 | A |
4014461 | Harvill | Mar 1977 | A |
4015819 | Zahid | Apr 1977 | A |
4041209 | Scholle | Aug 1977 | A |
4062475 | Harris et al. | Dec 1977 | A |
4087026 | Petterson | May 1978 | A |
4093068 | Smrt | Jun 1978 | A |
4137930 | Scholle | Feb 1979 | A |
4138036 | Bond | Feb 1979 | A |
4148416 | Gunn-Smith | Apr 1979 | A |
4150696 | Meier et al. | Apr 1979 | A |
4152184 | Bacehowski | May 1979 | A |
4159790 | Bailey | Jul 1979 | A |
4193518 | Holmes | Mar 1980 | A |
4214675 | Schmit | Jul 1980 | A |
4224367 | Scholle | Sep 1980 | A |
4257535 | Mellett | Mar 1981 | A |
4258863 | Ness | Mar 1981 | A |
4265373 | Stoody | May 1981 | A |
4266692 | Clark | May 1981 | A |
4269884 | Della Vecchia et al. | May 1981 | A |
4270533 | Andreas | Jun 1981 | A |
4275823 | Credle, Jr. | Jun 1981 | A |
4284671 | Cancio et al. | Aug 1981 | A |
4286636 | Credle | Sep 1981 | A |
4322020 | Stone | Mar 1982 | A |
4326574 | Palaroni et al. | Apr 1982 | A |
4362255 | Bond | Dec 1982 | A |
4375864 | Savage | Mar 1983 | A |
4381846 | Heck | May 1983 | A |
4445539 | Credle | May 1984 | A |
4445550 | Davis et al. | May 1984 | A |
4449243 | Platel | May 1984 | A |
4484697 | Fry, Jr. | Nov 1984 | A |
4513884 | Magid | Apr 1985 | A |
4524458 | Pongrass et al. | Jun 1985 | A |
4551379 | Kerr | Nov 1985 | A |
4576283 | Fafournoux | Mar 1986 | A |
4579756 | Edgel | Apr 1986 | A |
4600130 | Libit | Jul 1986 | A |
4601410 | Bond | Jul 1986 | A |
4683702 | Vis | Aug 1987 | A |
4815631 | Eeg et al. | Mar 1989 | A |
4893731 | Richter | Jan 1990 | A |
5006056 | Mainstone et al. | Apr 1991 | A |
5024354 | Ledewiz | Jun 1991 | A |
5147071 | Rutter | Sep 1992 | A |
5232535 | Brinley | Aug 1993 | A |
5385564 | Slater | Jan 1995 | A |
RE34929 | Kristen | May 1995 | E |
5647511 | Bond | Jul 1997 | A |
5728086 | Niedospial, Jr. | Mar 1998 | A |
5743435 | Tomic | Apr 1998 | A |
5749493 | Boone et al. | May 1998 | A |
5915596 | Credle, Jr. | Jun 1999 | A |
5928762 | Aizawa et al. | Jul 1999 | A |
5941421 | Overman et al. | Aug 1999 | A |
6012611 | Schroeder | Jan 2000 | A |
6045006 | Frazier et al. | Apr 2000 | A |
6073807 | Wilford et al. | Jun 2000 | A |
6102252 | Overman et al. | Aug 2000 | A |
6179173 | Frazier et al. | Jan 2001 | B1 |
6223981 | Gunder | May 2001 | B1 |
6500559 | Hofmeister et al. | Dec 2002 | B2 |
6533884 | Mallik | Mar 2003 | B1 |
6715644 | Wilford | Apr 2004 | B2 |
20030089737 | Wilford | May 2003 | A1 |
20030136798 | Wilford | Jul 2003 | A1 |
20040065402 | Knoerzer et al. | Apr 2004 | A1 |
Number | Date | Country |
---|---|---|
1153974 | Nov 2001 | EP |
732761 | Jun 1955 | GB |
756093 | Aug 1956 | GB |
1 473 524 | May 1977 | GB |
8301605 | May 1983 | WO |
8504383 | Oct 1985 | WO |
WO 200018836 | Apr 2000 | WO |
0136276 | May 2001 | WO |
Number | Date | Country | |
---|---|---|---|
20030127178 A1 | Jul 2003 | US |