Patent ID: 9617059
Date: 2017-04-11
CPC Classifications: B29D,B29K,B32B,B65D,C08J,Y10T

Claim:
1. A composite barrier film comprising (A) a base layer defining a base layer thickness, the base layer comprising a core layer comprising a polymer of polyester, and (B) a barrier layer coextensively adjacent in direct contact with one side of the base layer, the barrier layer defining a barrier layer thickness and comprising modified polyvinyl amine, in which the modified polyvinyl amine is a vinylamine polymer crosslinked by citric acid, in which the composite barrier film is optically clear, and in which the composite barrier film has moisture vapor transmission rate and oxygen transmission rate at most equal to that of a composite control film consisting essentially of a substrate identical to the base layer, and a layer of polyvinyl alcohol of thickness equal to the barrier layer thickness and disposed coextensively on the substrate.