Patent ID: 9469788
Filing Date: 2016-10-18
CPC Classification: B32B,C08K,C08L,C09D,C09J,Y10T

Claim Text:
1. A two-layer, more than 50% by weight biodegradable removable protective film or liner film consisting of (a) one backing layer based on at least one biodegradable polymer selected from the group consisting of lactic acid homopolymers, lactic acid copolymers, polylactides, polyhydroxyalkanoates, thermoplastic starch, polyester, at least partly hydrolyzed polyvinyl acetates, ethylene-vinyl alcohol copolymers, copolymers of at least two monomers of the stated polymers, and mixtures of at least two of the stated polymers and (b) one release layer based on at least one cured polysiloxane which curing is based at least partly on a reaction with at least one crosslinking monomeric or oligomeric additive, said additive also causing the adhesion between the backing layer (a) and the release layer (b), and no adhesion layer is present between the backing layer (a) and the release layer (b), whereby the additive used contains no siloxane groups, and has at least two functional groups of which at least one is a functional group containing at least one carbon double bond and at least one functional group not consumed by the curing of the polysiloxane causing said adhesion promotion between the backing layer (a) and the release layer (b), which is selected from the group consisting of hydroxyl groups, carboxyl groups, and acid anhydride groups.