| abstract |
Production of plasticized polyvinyl butyral films with improved optical properties and reduced yellowing by mixing polyvinyl butyral (PVB) and plasticizer, in which an effective amount of an optical brightener is dissolved or suspended, and optionally other additives and auxiliaries, plasticizing the mixture and thermoplastic molding, preferably by Extrusion or calendering, preferably to form flat films with a thickness of 0.2 to 2 mm, in particular 0.3 to 0.8 mm. Use of the flat films as interlayer films in the production of multilayer laminated glass panes, preferably silicate panes. |