Patent ID: 9663281
Date: 2017-05-30
CPC Classifications: B29C,B29D,B32B,B65B,B65D

Claim:
1. A packaging film comprising at least four layers of coextruded film, wherein a) at least two of the at least four layers are high temperature resistant layers each comprising a high melting temperature polymer or a blend of two or more high melting temperature polymers, b) at least one of the at least four layers is a low melting temperature sealing layer comprising a low melting temperature polymer or a blend of two or more low melting temperature polymers, and c) at least one of the at least four layers is an adhesive layer between, and immediately adjacent to, a high temperature resistant layer and a low melting temperature sealing layer, said adhesive layer comprising a material selected for suitability for bonding the high melting polymer to the low melting polymer, which packaging film is suitable for forming an ultrasonic seal.