Release films formed by coextrusion
AssigneeAvery Dennison Corporation
InventorsDaniel R. Logue, Piet T. Van Emmerik, Roger H. Mann, Edward I. Sun, Gary A. Avalon, Carol A. Caldwell, Eng-Pi Chang, Richard A. Huskey
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Abstract
A release liner providing a release surface which comprises a first olefin polymer film formed having dispersed therein by high shear mixing a release substance which is polyethyleneimine octadecyl carbamide, polyvinyl octadecyl carbamate or a mixture thereof, coextruded or cocast onto a film formed from a second olefin polymer. The release liner has particular utility in diaper tape application.
Claims9
A laminate release film providing a release surface which comprises a first film formed from a first olefin polymer selected from the group consisting of low density ethylene homopolymers, high density ethylene homopolymers, ethylene-propylene copolymers containing up to about 50% by weight propylene, blends of polyethylene with ethylene-propylene copolymers, polypropylene and mixtures thereof having uniformly dispersed therein by dry blending using high shear mixing a release agent selected from the group consisting of polyethyleneimine octadecyl carbamide, polyvinyl octadecyl carbamate and mixtures thereof present in an amount of from about 0.1 to about 20 percent by weight based on the weight of the first olefin polymer and release agent, said first film coextruded with or cocast onto and permanently bonded to a second olefin polymer fill, provided to stiffen the first olefin polymer fill, the second olefin polymer film selected from the group consisting of isotactic polypropylene and copolymers of propylene with at least one other olefin monomer containing 2 or 4 carbon atoms and in which the monomer is present in an amount up to about 10% by weight of the copolymer.
Dependencies are inferred from the claim text.