PREPOLYMERBASIERTE POLYURETHANFORMULIERUNGEN ZUR HERSTELLUNG HOLOGRAPHISCHER FILME

摘要

Polyurethane composition comprises: (a) a polyisocyanate component comprising an isocyanate (NCO)-terminated polyurethane prepolymer; (b) isocyanate-reactive polyether polyol; (c) an urethane acrylate and/or urethane methacrylate comprising at least one aromatic structural unit and a refractive index of greater than 1.50 at 405 nm; (d) a free radical stabilizer; (e) a photoinitiator based on a combination of a borate salt and a dye; (f) optionally a catalyst; and (g) optionally an auxiliary and/or an additive. Polyurethane composition comprises: (a) a polyisocyanate component comprising an isocyanate (NCO)-terminated polyurethane prepolymer, where the NCO groups of the NCO-terminated polyurethane prepolymer are primarily aliphatically bonded, and the NCO-terminated polyurethane prepolymer is based on hydroxyl (OH)-functional compounds having an OH functionality of 1.6-2.05; (b) NCO-reactive polyether polyol; (c) an urethane acrylate and/or urethane methacrylate comprising at least one aromatic structural unit and a refractive index of greater than 1.50 at 405 nm, where the urethane acrylate and/or urethane methacrylate is free of NCO groups and OH groups; (d) a free radical stabilizer; (e) a photoinitiator based on a combination of a borate salt and a dye having an absorption band which at least partly covers the spectral of 400-800 nm; (f) optionally a catalyst; and (g) optionally an auxiliary and/or an additive. Independent claims are included for: (1) producing a medium for recording visual holograms comprising applying the polyurethane composition to a substrate or in a mold and curing the polyurethane composition; (2) a medium for recording visual holograms produced by the process; and (3) an optical element or image comprising the medium.