Retort-sterilizable pouch
AssigneeShell Oil Company
InventorsCarl W. Schroeder, Joseph R. Webster
Life of this patent
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Abstract
In a retort-sterilizable laminated structure comprising an aluminum foil or sheet, a heat-sealable polymer layer, and a heat-resistant resin layer, the heat-sealable layer is the cracked product of the blend of a poly(propylene-ethylene) copolymer and an ethylene-vinyl acetate copolymer. This heat-sealable layer composition has improved flow properties and may be extrusion-coated onto a metal film substrate at high speeds.
Claims9
In a retort-sterilizable laminated structure comprising an aluminum foil or sheet, a heat-sealable polymer layer on one surface of said aluminum foil or sheet, and a heat-resistant resin layer formed on the other surface of said aluminum foil or sheet, the improvement wherein said heat-sealable polymer layer is formed from the composition comprising the cracked product of a blend of a polypropylene copolymer and an ethylene-vinyl acetate copolymer wherein:
- (a) the melt flow of said cracked product is between about 15 and about 65 grams per 10 minutes, condition L;
- (b) said polypropylene copolymer is a propylene-ethylene copolymer comprising between about 1 and about 10 percent by weight ethylene and has a melt flow of between about 0.5 and about 15 grams per 10 minutes, condition L;
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- (c) said ethylene-vinyl acetate copolymer has a vinyl acetate content of between about 15 and about 30 percent by weight, and has a melt flow of between about 1 and about 30 grams per 10 minutes, condition E.
Dependencies are inferred from the claim text.