Biodisintegratable composite foils

摘要

The use of an aqueous polyurethane dispersion adhesive is described for producing biodisintegratable composite foils where at least two substrates are adhesive-bonded to one another with use of the polyurethane dispersion adhesive, where at least one of the substrates is a biodisintegrable polymer foil. At least 60% by weight of the polyurethane is composed of diisocyanates, polyesterdiols, and at least one bifunctional carboxylic acid selected from dihydroxycarboxylic acids and diaminocarboxylic acids.

主权项

1. A biodistintegratable composite foil produced by a method, the method comprising:
adhesive-bonding at least one first substrate to at least one second substrate with an adhesive comprising a biodegradable aqueous dispersed polyurethane, thereby forming a biodisintegratable composite foil, wherein at least one of the at least one first substrate and the at least one second substrate is a biodisintegratable polymer foil, and at least 60% by weight of the biodegradable aqueous dispersed polyurethane comprises: (a) a diisocyanate; (b) a polyesterdiol; and (c) a bifunctional carboxylic acid selected from the group consisting of a dihydroxycarboxylic acid and a diaminocarboxylic acid, wherein said biodegradable aqueous dispersed polyurethane exhibits a ratio of gaseous carbon liberated therefrom in the form of CO2 to a total carbon content of a material of at least 30% after 20 days, and wherein at most 10% of an original dry weight of said biodisintegratable composite foil is found to be present after aerobic composting for a period of at most 12 weeks in a sieve fraction >2 mm.