Two-layer plastics film for safety glass - with polyurethane layer from co-polyester diol to reduce crystallisation

摘要

Plastic film consists of (A) a layer of aliphatic polyurethane cross-linked in 3 dimensions and with self-healing properties, and (B) a layer of thermoplastic polyurethane with linear structure, (B) is made from a co-polyester diol from >=2 branched and/or cycloaliphatic diols. Pref. >=2 different dicarboxylic acids are also used in working the copolyester diol. Used in mfr. of safety glass for use in vehicles, buildings sunglasses, protective masks, visors for safety helmets, etc. Layer (B) is adhered tot he glass by heat and pressure. Formation of crystalline agglomerates in (B) causing clouding of the layer with time, esp. at higher temps., is strongly retarded.