Dual web package having improved gaseous exchange

• US 5,686,126 A
• Filed: 06/06/1995
• Issued: 11/11/1997
• Est. Priority Date: 06/06/1995
• Status: Expired due to Term

• Current Assignee: Cryovac Incorporated (Sealed Air)
• Original Assignee: W R Grace & Company - CONN (WR Grace & Company)
• Inventors: Stockley, H. Walker III, Barmore, Charles R., Noel, David C., Troutt, E. Susanne
• Primary Examiner(s): Kepplinger, Esther
• Assistant Examiner(s): SHERRER, CURTIS EDWARD
• Application Number:
  US08/471,065
• Time in Patent Office: 889 Days
• Field of Search: 426/118, 426/127, 426/396, 426/415, 426/129, 206/484, 206/484.1, 206/484.2, 428/43, 428/172, 428/304.4
• US Class Current: 426/127
• CPC Class Codes: B32B 2250/02 2 layers
• CPC Class Codes: B32B 2250/24 All layers being polymeric
• CPC Class Codes: B32B 2307/724 Permeability to gases, adsorption
• CPC Class Codes: B32B 2323/04 Polyethylene
• CPC Class Codes: B32B 2331/04 Polymers of vinyl acetate, e.g. PVA
• CPC Class Codes: B32B 2333/08 Polymers of acrylic acid esters, e.g. PMA, i.e. polymethylacrylate
• CPC Class Codes: B32B 2439/70 Food packaging
• CPC Class Codes: B32B 27/08 of synthetic resin
• CPC Class Codes: B32B 27/306 comprising vinyl acetate or vinyl alcohol (co)polymers
• CPC Class Codes: B32B 27/308 comprising acrylic (co)polymers
• CPC Class Codes: B32B 27/32 comprising polyolefins comprising vinyl (co)polymers or acrylic (co)polymers B32B27/30
• CPC Class Codes: B32B 3/266 characterised by an apertured layer, the apertures going through the whole thickness of the layer, e.g. expanded metal, perforated layer, slit layer regular cells B32B3/12
• CPC Class Codes: B32B 37/153 at least one layer is extruded and immediately laminated while in semi-molten state
• CPC Class Codes: B32B 7/06 permitting easy separation
• CPC Class Codes: B32B 7/12 using interposed adhesives or interposed materials with bonding properties
• CPC Class Codes: B65D 2565/388 Materials used for their gas-permeability
• CPC Class Codes: B65D 2577/2025 Multi-layered container, e.g. laminated, coated
• CPC Class Codes: B65D 2577/2091 in cover
• CPC Class Codes: B65D 77/2024 the cover being welded or adhered to the container
• CPC Class Codes: B65D 81/20 under vacuum or superatmospheric pressure, or in a special atmosphere, e.g. of inert gas B65D81/28 takes precedence; containers with pressurising means for maintaining ball pressure A63B39/025
• CPC Class Codes: Y10T 428/15 : Sheet, web, or layer weakened to permit separation through thickness
• CPC Class Codes: Y10T 428/24612 : Composite web or sheet
• CPC Class Codes: Y10T 428/249953 : Composite having voids in a component [e.g., porous, cellular, etc.]

Abstract

A package which allows for butchering and packaging of fresh red meat at a centralized facility is provided which includes a an impermeable tray supporting the product, a first film sealed to the tray for enclosing the product, means defined within the first film for exchanging gases into and out of the package, and a second impermeable film enclosing the first film, such that removal of said impermeable film provides for the exchange of gases into and out of the package. The means for exchanging gases may be perforations defined within the first film, a second highly permeable film sealed to the first film, or an enlarged opening formed within the first film which is enclosed with a patch following adequate gas exchange at retail. Such gas exchange is required to release any low oxygen atmosphere and allow for the introduction of oxygen to the packaged meat product. Said means for exchanging gases having a gas transmission rate of at least about 50,000 cc/m² /24 hrs./atm. at 73° F.

Claims

1. A package for a product, comprising:

a product;

a substantially gas-impermeable support member supporting the product; and

a multilayer web sealed to the support member for enclosing the product, said multilayer web comprising a substantially gas-impermeable film and a multilayer gas-permeable film and being delaminatable within said multilayer gas-permeable film, said multilayer gas-permeable film being directly adjacent and sealed to said support member such that, upon delamination of said multilayer multilayer web, one portion of said multilayer gas-permeable film remains sealed to said support member while the remaining portion of said multilayer gas-permeable film is removed from said support member along with said gas-impermeable film.

2. The package of claim 1, wherein delamination of said multilayer web exposes at least one channel within said multilayer gas-permeable film, said at least one channel allowing for a free flow of gases into and out of said package.

3. The package of claim 1, wherein said multilayer gas-permeable film is a coextruded, multilayer film.

4. The package of claim 1, wherein said multilayer gas-permeable film is perforated.

5. The package of claim 4, wherein said multilayer gas-permeable film is a coextruded, multilayer film.

6. The package of claim 4, wherein said multilayer gas-permeable film comprises a gas-permeable material.

7. The package of claim 4, wherein said multilayer gas-permeable film comprises a substantially gas-impermeable material but is rendered gas-permeable as a result of being perforated.

8. The package of claim 1, wherein said multilayer gas-permeable film is partially perforated.

9. The package of claim 1, wherein said multilayer gas-permeable film is laminated to said gas-impermeable film and the force required to delaminate said multilayer gas-permeable film into two separate portions is less than the force required to delaminate said gas-impermeable film from said multilayer gas-permeable film, whereby, the portion of said gas-permeable film which is removed from said support member upon delamination of said multilayer web remains laminated to said gas-impermeable film.

10. The package of claim 4, wherein said multilayer gas-permeable film is laminated to said gas-impermeable film and the force required to delaminate said multilayer gas-permeable film into two separate portions is less than the force required to delaminate said gas-impermeable film from said multilayer gas-permeable film, whereby, the portion of said multilayer gas-permeable film which is removed from said support member upon delamination of said multilayer web remains laminated to said gas-impermeable film.

11. The package of claim 5, wherein said multilayer gas-permeable film is laminated to said gas-impermeable film and the force required to delaminate said multilayer gas-permeable film into two separate portions is less than the force required to delaminate said gas-impermeable film from said multilayer gas-permeable film, whereby, the portion of said multilayer gas-permeable film which is removed from said support member upon delamination of said multilayer web remains laminated to said gas-impermeable film.