W. R. Grace Co.

W. R. Grace & Co., Cryovac Div.

Alan S Weinberg

Joseph F Porinchak

Harri J Brax

Henry G Schirmer

Joseph Z Sun

Walter B Mueller

Julian H Schoenberg

Norman D Bornstein

Philip T Voso

Mario Gillio-Tos

B Gary Wofford

Donald J D'Entremont

A shrink bag having an integral carrying handle is provided that includes an extended lip bag of a heat shrinkable thermoplastic material and having a carrying hole in the lip with a continuous fused bead around its periphery, the carrying hole being spaced sufficiently below the top of the lip such that upon heat shrinking the bag about a product sealed therein enhanced thickening along the carrying-load bearing portion of the hole periphery occurs relative to the non-load bearing portion of the hole periphery. An associated method for making the bag is also provided.

Shrink bag with integral handle

A film of ethylene vinyl acetate having a narrow molecular weight distribution and a saran composition that is a blend of emulsion and suspension polymerized saran or a saran composition that includes emulsion polymerized saran of the type generally considered suitable for liquid coating. A laminate including the film and composition and the method for production thereof including sequentially melt extruding tubular films of ethylene vinyl acetate which is irradiated, saran and ethylene vinyl acetate and then bubble orienting the three-ply laminate. The laminate is employed for packaging and forming packages of bone-in fresh red meat.

Ethylene-vinyl acetate copolymer film laminate

The multi-layer polyester/polyolefin shrink film of this invention provides a combination of shrink tension, hot seal strength, sealability, and shrink temperature range heretofore unobtainable in an oriented, monolayer polyolefin material. The preferred film has five layers in which the middle layer comprises a polyester or copolyester, two inner layers adjacent the middle layer comprise ethylene-vinyl actate copolymer, and the skin or outer layers comprise an ethylene-propylene copolymer.

Multi-layer polyester/polyolefin shrink film

Saran blended with butyl rubber exhibits a good balance of melt extrudability and oxygen barrier properties.

Blends of butyl rubber and polymers of vinylidene chloride

The multi-layer polyester/polyolefin shrink film of this invention provides a combination of shrink tension, hot seal strength, sealability, and shrink temperature range heretofore unobtainable in an oriented, monolayer polyolefin material. The preferred film has five layers in which the middle layer comprises a polyester or copolyester, two inner layers adjacent the middle layer comprise ethylene-vinyl acetate copolymer, and the skin or outer layers comprises an ethylene-propylene copolymer.

This invention is a process for making a self-welding packaging film by blending at least two ethylene polymers, one of the polymers having a melt flow substantially greater than any of the other polymers in the blend, and thereafter extruding a film from the blend. The film may be self-supporting or it may be an inner layer in a multi-ply film. Preferred ethylene polymers for the blend are the ethylene-vinyl acetate copolymers wherein one copolymer has a melt flow of less than 5.0 and the other has a melt flow greater than 28.0.

Self-welding packaging film

This invention is a self-welding packaging film made by blending at least two ethylene polymers, one of the polymers having a melt flow substantially greater than any of the other polymers in the blend, and thereafter extruding a film from the blend. The film may be self-supporting or it may be an inner layer in a multi-ply film. Preferred ethylene polymers for the blend are the ethylene-vinyl acetate copolymers wherein one copolymer has a melt flow of less than 5.0 and the other has a melt flow greater than 28.0.

Packaging film comprising a blended self-welding layer

A melt extrusion process is taught which employs a saran of the type generally considered suitable for liquid coating.

Process for melt extruding coating grade saran

A heat shrinkable multi-layer packaging film having a layer of a hydrolyzed ethylene-vinyl acetate copolymer. Preferably, the film is formed by coextruding the hydrolyzed ethylene-vinyl acetate copolymer layer between two other polymeric layers, at least one of which is cross-linkable, and thereafter irradiating and orienting the multi-layer structure. The resulting film is heat shrinkable and has very low oxygen permeability.

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Greenville, SC, United States of America

Alan S Weinberg