Resealable package film
A package film is provided for attaching to a base member to define a package. The package film construction includes a top layer having a top surface and a bottom surface. A removable adhesive is provided having a defined pattern applied below the bottom surface. A polyethylene (PE) emulsion layer is provide that covers at least a portion of the adhesive pattern, with the PE emulsion layer being heat sealable to the base member.
Latest Sonoco Development, Inc. Patents:
This is an application for reissue of U.S. Pat. No. 8,746,490. A related continuation reissue application Ser. No. 18/598,397, with a filing date of Mar. 7, 2024, is co-pending with the present reissue application.
FIELD OF THE INVENTIONThe present application relates to a film for a package that is separable from the package base portion and then may be resealed. In one specific embodiment, the package is a container having a film lidding attached to a flange on the container.
BACKGROUND OF THE INVENTIONA number of packaging forms are known. In one form, a thermoform tray is provided for retaining a product, with a flexible film forming a seal for the tray. The tray may include a peripheral flange and the film is attached to the flange. The attachment of the film to the flange may be accomplished by a variety of means, such as heat sealing, adhesives, etc. The film may be separable from the flange to gain access to the contents and the film or a portion thereof may be resealed by means of an adhesive.
It is known to use a hot-melt pressure sensitive adhesive (PSA) that is extruded between film layers of polyethylene terephthalate (PET) and polyethylene (PE) to create a resealable lidding layer. This structure requires adhesive applied as a 100% coverage coating (i.e., not pattern applied between the PET and PE layers).
U.S. Pat. No. 4,206,844 to Thukanato et al. shows a package with a cover sheet that is peelable for the package base and the resealable. The package body is formed of a laminate having a paper substrate, a polyester emulsion layer and a thermoplastic resin emulsion layer on the polyester emulsion layer. A heat seal is formed between the cover sheet and the thermoplastic resin emulsion layer to seal the package. When the cover sheet is peeled back, a portion of the thermoplastic resin layer is broken at the heat seal.
U.S. Pat. No. 4,364,989 to Moyle shows a package material for use in retaining snack foods. The package material is composed of multiple layers with an outer layer of polypropylene (PP), a low-density polyethylene (PE) laminate and an inner layer of a co-extrusion material. Emulsion layers of polyvinyl chloride (PVC) are provided between the packaging layers and are used to create a heat sealant in the formation of the package.
U.S. Pat. No. 3,454,210 to Spiegel et al. shows a multilayer package having a central, rupturable, preformed-film layer of polyethylene (PE). The rupturable film is formed adjacent a layer of pressure sensitive adhesive (PSA). A heat seal is formed to secure the rupturable film to the base layer in the sealed package.
U.S. Pat. No. 5,518,790 to Huber et al shows a multilayer package for sealing an aromatic substance. A central layer formed from a foamed polypropylene is provided between a barrier layer in a top laminate and the base layers in the package. The top layer is secured to the foamed polypropylene (PP) by an adhesive. The separation of the top layer is indicated to result from the difference in density of the top layer and the foamed PP.
SUMMARY OF THE INVENTIONIn one aspect of the present disclosure, a film is provided for attaching to a base member to define a package. The package film construction includes a top layer having a top surface and a bottom surface. A removable adhesive is provided having a defined pattern applied below the bottom surface. A polyethylene (PE) emulsion layer is provide that covers at least a portion of the adhesive pattern, with the PE emulsion layer being heat sealable to the base member.
In a further aspect of the construction, an ink layer may be provided. The ink layer may further be applied to the bottom surface of the top layer, or as otherwise desired. A bottom layer may be provided below the bottom surface, with the bottom layer secured to the ink layer and the adhesive pattern applied below the bottom layer. The bottom layer may further be secured to the top layer and/or the ink layer by means of a permanent adhesive.
In a further aspect of the package film, the PE emulsion layer is pattern applied to cover the adhesive pattern. Alternatively, the PE emulsion layer may be continuously applied below the bottom surface of the top layer and over the adhesive pattern.
In a further aspect of the disclosure, the top layer may be a polyethylene terephthalate (PET) material.
In a further aspect of the disclosure, the adhesive pattern conforms to at least a portion of the periphery of the base member of the package. Further, the PE emulsion may be applied over the entire pattern of the removable adhesive. Alternatively, the PE emulsion may conform to a portion of the adhesive pattern. The adhesive is contemplated to form a more permanent bond in the areas where the PE emulsion is absent.
In a further aspect of the disclosure, a resealable package is defined including a package film having a top layer, the top layer having a top surface and a bottom surface. A removable adhesive is applied in a pattern below the bottom surface and a polyethylene (PE) emulsion layer is provided for covering at least a portion of the adhesive pattern. A package base is provided having a peripheral portion. The pattern of the removable adhesive on the film preferably conforms to the peripheral portion of the base. A skin portion is further provided on the peripheral portion, with the skin portion being heat-sealable to the PE emulsion layer. The PE emulsion layer is heat-sealed to the skin portion and emulsion transforms to a material having film-like properties during heating. The removable adhesive is separable from the transformed PE film-like material for separating the top layer from the base, with the removable adhesive being resealable to the transformed PE film for closing the package.
In a further aspect of the disclosure, a method of forming a resealable package is defined. A package film is provided having a top layer, the top layer having a top surface and a bottom surface. A removable adhesive is provided in a defined pattern below the bottom surface of the package film. A polyethylene (PE) emulsion layer is applied in a pattern covering at least a portion of the removable adhesive pattern. A base is provided having a peripheral portion, with the package film positioned in contact with the base. The pattern of the removable adhesive conforms to the peripheral portion of the base and wherein the PE emulsion is in contact with the peripheral portion of the base. The package film is heat-sealed to the peripheral portion of the base, with the applied heat transforming the PE emulsion to a film-like material. The PE emulsion film-like material is attached to the base with the top layer being separable along with the removable adhesive to open the package. The top layer is resealable to the peripheral portion of the base by means of the removable adhesive.
Other features of the present invention will become apparent from the detailed description to follow, taken in conjunction with the accompanying drawings.
For the purpose of illustrating the invention, the drawings show one or more forms that are presently preferred. It should be understood that the invention is not limited to the precise arrangements and instrumentalities shown.
In the figures, where like numerals identify like elements, there is shown an embodiment of a package that in
A partial cross section of the constituent parts of the film 18 and tray 12 of the package 10 is shown in
The package film 18 includes a number of layers, but may be composed of a single base layer or a number of laminated layers. As shown, a polyethylene terephthalate (PET) top layer 20 is provided on its bottom surface with a layer of ink 22. The ink layer 22 is contemplated to form a decorative pattern on the package 10 (shown as “Indicia” in
A coating 30 is applied over the patterned adhesive 28. The coating 30 is a thin layer of a polyethylene (PE) emulsion (such as, MED688 from Michelman, Inc. of Cincinnati, Ohio) and is applied in a pattern that overlaps the adhesive 28. The PE emulsion 30 is typically applied wet and is dried in a relatively low temperature oven (for example, at 170° F.) or by other means. The PE emulsion 30 covers the adhesive 28, such that the package film 18 may be rolled or stacked prior to application to the tray 12 or otherwise utilized.
The package film 18 is cut to size and aligned with the tray flange 16. The flange 16 preferably includes a skin layer 32, which is preferably also a PE material. The film 18 is heat-sealed to the flange 16 and forms the structure shown in
The PE emulsion 30, as shown in
The PE film layer 30′ is adhered to the skin layer 32 to seal the tray 12. The package film 18 may be separated from the flange 16, as is graphically illustrated in
In
The top layers (20, 36) or bottom layer (26) in the above examples may be provided with polyvinylidene chloride (PVDC), nanoclay (NANO), polyvinyl alcohol (PVOH), ethylene vinyl alcohol (EVOH) materials. Other barrier materials/layers may also serve to improve performance, including a PET film metalized with aluminum oxide (AlOx) vapor deposition or a film having a silicon oxide (SiOx) coating. Such materials/layers are contemplated to serve as a moisture and/or oxygen barrier. Another variation of the package film structure may include the application of a PE emulsion layer continuously across the bottom surface of top layer(s). This continuous emulsion layer would serve as a coating for any ink layer. Only a portion of the continuous PE emulsion layer fuses to the flange of the tray or other package surface during the heat-seal step. It is contemplated that the PE emulsion layer would be fragile enough to split at the end of the adhesive pattern, in the area where the heat-sealing did not occur. Hence, the pattern adhesive material would be exposed, with a portion of the PE layer adhered to the flange (etc.). The other portion of the PE emulsion remains adhered to the underside of the package film.
Other variations of the structures shown may include an adhesive pattern that conforms to only a portion of the periphery of the base of the package. Further, the PE emulsion may be applied over the entire pattern of the removable adhesive or, alternatively, the PE emulsion may conform to a portion of the adhesive pattern. The adhesive is contemplated to form a more permanent bond in the areas where the PE emulsion is absent. The portion of the resealable adhesive within the pattern that is exposed after the heat-sealed PE material separates from the package film forms the means for repeatedly resealing the package.
In the presently contemplated structures, die cutting or laser scoring of the layers is not required to create the separation of the lidding from the flange of the tray. However, in some structures and variations, a score line or other separation pattern may be used to create a desired function within the package. It is further noted that the contemplated structures incorporating a PE emulsion material may be used within other types of packages. For example, a similar separation and resealing function may be created with a flexible package material to form a pouch-like structure. The adhesive pattern and the PE emulsion coating are contemplated to conform to at least a portion of the sealing periphery of the base package portion.
The present disclosure shows and describes a number of exemplary embodiments. It should be understood by those skilled in the art from the foregoing that various other changes, omissions and additions may be made therein, without departing from the spirit and scope of the contemplated invention, with the scope of the invention being defined by the foregoing claims.
Claims
1. A film construction for attaching to a base member to define a package, the film construction comprising:
- a top layer, the top layer having a top surface and a bottom surface,
- a removable adhesive having a defined pattern applied below the bottom surface, and
- a polyethylene (PE) emulsion layer, covering at least a portion of the adhesive pattern, wherein the PE emulsion layer is heat sealable.
2. A film construction as in claim 1, further comprising an ink layer.
3. A film construction as in claim 2, wherein the ink layer is applied to the bottom surface of the top layer.
4. A film construction as in claim 3, further comprising for attaching to a base member to define a package, the film construction comprising:
- a top layer, the top layer having a top surface and a bottom surface,
- a removable adhesive having a defined pattern applied below the bottom surface,
- a polyethylene (PE) emulsion layer, covering at least a portion of the adhesive pattern, wherein the PE emulsion layer is heat sealable; and
- an ink layer, wherein the ink layer is applied to the bottom surface of the top layer; and
- a bottom layer, the bottom layer secured to the ink layer, below the bottom surface of the top layer, and the adhesive pattern applied to a bottom surface of the bottom layer.
5. A film construction as in claim 4, wherein the bottom layer is secured by means of a permanent adhesive.
6. A film construction as in claim 1 4, wherein the PE emulsion layer is pattern applied to cover the adhesive pattern.
7. A film construction as in claim 1 for attaching to a base member to define a package, the film construction comprising:
- a top layer, the top layer having a top surface and a bottom surface,
- a removable adhesive having a defined pattern applied below the bottom surface, and
- a polyethylene (PE) emulsion layer, covering at least a portion of the adhesive pattern, wherein the PE emulsion layer is heat sealable,
- wherein the PE emulsion layer is continuously applied below the bottom surface of the top layer and over the adhesive pattern.
8. A film construction as in claim 1 7, wherein the top layer is a polyethylene terephthalate (PET) material.
9. A film construction as in claim 1 4, wherein the PE emulsion layer is applied over the entire pattern of the removable adhesive.
10. A film construction as in claim 1 7, wherein the adhesive pattern conforms to a periphery of the top layer.
11. A resealable package comprising:
- a package film having a top layer, the top layer having a top surface and a bottom surface, a removable adhesive applied in a pattern below the bottom surface, and a polyethylene (PE) emulsion layer, covering at least a portion of the adhesive pattern, and
- a base, the base having a peripheral portion, the pattern of the removable adhesive on the film conforming to the peripheral portion of the base, and a skin portion on the peripheral portion, the skin portion being heat-sealable to the PE emulsion layer,
- wherein the PE emulsion layer is heat-sealed to the skin portion and the PE emulsion transforms to a film during heat-sealing, and
- wherein the removable adhesive is separable from the transformed PE film for separating the top layer from the base, and the removable adhesive being resealable to the transformed PE film for closing the package.
12. A resealable package as in claim 11, wherein the base is formed as a tray having one or more upstanding side walls defining a package form, and wherein the peripheral portion is a flange that surrounds the package form.
13. A resealable package as in claim 12, wherein the tray is formed from a substantially rigid material.
14. A resealable package as in claim 13, wherein the skin portion is a PE layer adhered to the flange.
15. A resealable package as in claim 11, wherein the package film further comprises an ink layer.
16. A resealable package as in claim 15, wherein the ink layer is applied to the bottom surface of the top layer.
17. A resealable package as in claim 16, wherein the package film further comprises a bottom layer, the bottom layer secured to the ink layer and the bottom surface of the top layer, the adhesive pattern applied to a bottom surface of the bottom layer.
18. A resealable package as in claim 17, wherein the bottom layer is secured by means of a permanent adhesive.
19. A resealable package as in claim 11, wherein the PE emulsion layer is continuously applied across the bottom surface area of the top layer and the adhesive pattern.
20. A resealable package as in claim 11, wherein the PE emulsion layer is applied over the entire pattern of the removable adhesive.
21. A method of forming a resealable package, comprising the steps of:
- providing a package film having a top layer, the top layer having a top surface and a bottom surface,
- applying a removable adhesive in a defined pattern below the bottom surface of the package film,
- applying a polyethylene (PE) emulsion layer in a pattern covering at least a portion of the removable adhesive pattern,
- providing a base, the base having a peripheral portion,
- placing the package film in contact with the base, wherein the pattern of the removable adhesive conforms to the peripheral portion of the base and wherein the PE emulsion is in contact with the peripheral portion of the base,
- heat-sealing the package film to the peripheral portion of the base, with the applied heat transforming the PE emulsion to a film material,
- separating the PE emulsion film and the base from the top layer and the removable adhesive to open the package, and
- resealing the removable adhesive to the peripheral portion.
22. A method as in claim 21, further comprising the step of:
- providing a skin portion on the peripheral portion of the base, the skin portion being heat-sealable to the PE emulsion layer.
23. A method as in claim 21, wherein the base is formed as a tray having one or more upstanding sidewalls and defines a package form, and wherein the peripheral portion is formed as a flange that surrounds the package form.
24. A method of forming a resealable package as in claim 23, wherein the tray is thermoformed.
25. A method as in claim 23 22, wherein the skin portion is in the form of a PE layer adhered to the flange.
26. A method as in claim 21, further comprising the step of providing an ink layer on the bottom surface of the package film.
27. A method as in claim 21, further comprising the step of securing a bottom layer, the bottom surface layer secured to the ink layer and the bottom surface of the top layer, and wherein the adhesive pattern is applied to a bottom surface of the bottom layer.
28. A method as in claim 21 27, wherein the step of securing of the bottom layer includes applying a permanent adhesive.
29. A method as in claim 21, wherein the PE emulsion layer is continuously applied over the bottom surface and the adhesive pattern.
30. A method as in claim 21, wherein the removable adhesive PE emulsion layer is pattern applied over the entire pattern of the removable adhesive.
31. A resealable package comprising:
- a package film having a top layer, the top layer having a top surface and a bottom surface, a removable adhesive applied in a pattern below the bottom surface, and a polyethylene (PE) emulsion layer, applied to and covering at least a portion of the adhesive pattern, and
- a base, the base having a peripheral portion, the pattern of the removable adhesive on the film conforming to the peripheral portion of the base, and a skin portion on the peripheral portion, the skin portion being heat-sealable to the PE emulsion layer,
- wherein the PE emulsion layer is heat-sealed to the skin portion and the PE emulsion transforms to a film during heat-sealing, and
- wherein the removable adhesive is separable from the transformed PE film for separating the top layer from the base, and the removable adhesive being resealable to the transformed PE film for closing the package.
32. A method of forming a resealable package, comprising the steps of:
- providing a package film having a top layer, the top layer having a top surface and a bottom surface,
- applying a removable adhesive in a defined pattern below the bottom surface of the package film,
- applying a polyethylene (PE) emulsion layer to the removable adhesive in a pattern to cover at least a portion of the removable adhesive pattern,
- providing a base, the base having a peripheral portion,
- placing the package film in contact with the base, wherein the pattern of the removable adhesive conforms to the peripheral portion of the base and wherein the PE emulsion is in contact with the peripheral portion of the base,
- heat-sealing the package film to the peripheral portion of the base, with the applied heat transforming the PE emulsion to a film material,
- separating the PE emulsion film and the base from the top layer and the removable adhesive to open the package, and
- resealing the removable adhesive to the peripheral portion.
33. The film construction as in claim 4, wherein the PE emulsion layer is applied to the removable adhesive pattern.
34. The film construction as in claim 7, wherein the PE emulsion layer is applied to the removably adhesive pattern.
3328196 | June 1967 | Sincock |
3454210 | July 1969 | Spiegel |
3464832 | September 1969 | Mullinix |
RE27361 | May 1972 | Miller |
3938659 | February 17, 1976 | Wardwell |
3946872 | March 30, 1976 | Sturm |
3997677 | December 14, 1976 | Hirsch et al. |
4206844 | June 10, 1980 | Thukamoto et al. |
4364989 | December 21, 1982 | Moyle |
4381848 | May 3, 1983 | Kahn |
4438850 | March 27, 1984 | Kahn |
4469258 | September 4, 1984 | Wright et al. |
4673601 | June 16, 1987 | Lamping et al. |
4786534 | November 22, 1988 | Aiken |
4858780 | August 22, 1989 | Odaka et al. |
4915289 | April 10, 1990 | Hatano et al. |
4944409 | July 31, 1990 | Busche et al. |
5061532 | October 29, 1991 | Yamada |
5125529 | June 30, 1992 | Torterotot |
5145737 | September 8, 1992 | Boiron et al. |
5160767 | November 3, 1992 | Genske et al. |
5281453 | January 25, 1994 | Yamada et al. |
5382472 | January 17, 1995 | Yanidis et al. |
5518790 | May 21, 1996 | Huber et al. |
5709310 | January 20, 1998 | Kretz |
5714305 | February 3, 1998 | Teng |
5759650 | June 2, 1998 | Raines et al. |
5873483 | February 23, 1999 | Gortz et al. |
5882749 | March 16, 1999 | Jones et al. |
5882789 | March 16, 1999 | Jones et al. |
5915547 | June 29, 1999 | Chen |
6032800 | March 7, 2000 | Kocher |
6042862 | March 28, 2000 | Kocher et al. |
6056141 | May 2, 2000 | Navarini et al. |
6127023 | October 3, 2000 | Marbler et al. |
6165115 | December 26, 2000 | Rea |
6248380 | June 19, 2001 | Kocher et al. |
6302290 | October 16, 2001 | Engelaere |
6302324 | October 16, 2001 | Buchko |
6308853 | October 30, 2001 | Jud |
6410082 | June 25, 2002 | Pinell |
6436499 | August 20, 2002 | Krampe et al. |
6511723 | January 28, 2003 | Engelaere |
6627073 | September 30, 2003 | Wolf et al. |
6627273 | September 30, 2003 | Wolf et al. |
6670023 | December 30, 2003 | Mueller |
6722272 | April 20, 2004 | Jud |
6770050 | August 3, 2004 | Epstein |
6786994 | September 7, 2004 | Williams et al. |
6790508 | September 14, 2004 | Razeti |
6960392 | November 1, 2005 | Le Du et al. |
7422782 | September 9, 2008 | Haedt et al. |
7874731 | January 25, 2011 | Turvey et al. |
7927679 | April 19, 2011 | Cruz et al. |
8091323 | January 10, 2012 | Paterson |
8114451 | February 14, 2012 | Sierra-Gomez et al. |
8173233 | May 8, 2012 | Rogers et al. |
8202623 | June 19, 2012 | Dabadle et al. |
8507084 | August 13, 2013 | Deng |
8684217 | April 1, 2014 | Bruehl et al. |
9067391 | June 30, 2015 | Lu et al. |
20010001282 | May 17, 2001 | Parmentier et al. |
20020034649 | March 21, 2002 | Le Du et al. |
20020197425 | December 26, 2002 | Wolf et al. |
20030175509 | September 18, 2003 | Franko, Sr. |
20040016208 | January 29, 2004 | Mumpower et al. |
20040151932 | August 5, 2004 | Galloway |
20050252600 | November 17, 2005 | van Driesten |
20050276525 | December 15, 2005 | Hebert et al. |
20060124577 | June 15, 2006 | Ross |
20060172131 | August 3, 2006 | Haedt et al. |
20060233987 | October 19, 2006 | Mumpower |
20070237913 | October 11, 2007 | Hagino |
20080063821 | March 13, 2008 | Galloway |
20080152850 | June 26, 2008 | Paterson |
20090311454 | December 17, 2009 | Stephens |
20100172604 | July 8, 2010 | Andersson et al. |
20100247003 | September 30, 2010 | Huffer et al. |
20100323134 | December 23, 2010 | Bostian et al. |
20120067896 | March 22, 2012 | Daffner et al. |
20120187122 | July 26, 2012 | Glasow |
20150275032 | October 1, 2015 | Deak et al. |
2711579 | August 2009 | CA |
2888991 | February 2021 | CA |
0661154 | July 1995 | EP |
2917036 | August 2020 | EP |
0817551 | July 1996 | JP |
08175571 | July 1996 | JP |
2009111153 | September 2009 | WO |
- Honeywell A-C 325 description and properties, https://industrial.honeywell.com/us/en/products/performance-additives/paints-and-coatings/a-c-325 (Year: 2023).
- First examination report for corresponding CA 2,888,991, dated Jul. 11, 2019.
- Response to first examination report for corresponding CA 2,888,991, dated Jan. 10, 2020.
- Second examination report for corresponding CA 2,888,991, dated Apr. 7, 2020.
- Response to second examination report for corresponding CA 2,888,991, dated Aug. 30, 2020.
- Response to Rule 161 communication for corresponding EP appln. 13814273.2, dated Nov. 10, 2015.
- First examination report for corresponding EP appln. 13814273.2, dated May 15, 2019.
- Response to first examination report for corresponding EP appln. 13814273.2-1308, dated Dec. 8, 2019.
- International Search Report, PCT/US2013/068479, dated Mar. 14, 2014.
Type: Grant
Filed: Dec 23, 2021
Date of Patent: May 7, 2024
Assignee: Sonoco Development, Inc. (Hartsville, SC)
Inventors: Scott William Huffer (Hartsville, SC), Donavan Young (Hartsville, SC)
Primary Examiner: Terrence R Till
Application Number: 17/560,447
International Classification: B65D 77/20 (20060101); B32B 3/06 (20060101); B32B 3/10 (20060101); B32B 27/32 (20060101); B32B 27/36 (20060101); B65B 7/28 (20060101);