IR reflective elements made of impact-resistance plastic, and a process for their production

A plastic element which comprises an impact-resistant, thermoplastic plastic, and from 0.01 to 2 wt. % of IR-reflective particles comprising lamellar-shaped carrier pigments coated with a metal oxide, the plastic element being made by a process comprising:

• mixing said IR-reflective particles with a melt of a low-viscosity thermoplastic plastic at a temperature of at least 280° C. in a pressure-free, non-shearing zone of a twin-screw extruder to form a pre-mixture comprising from 5 to 40 wt. % of said IR-reflective particles;
• extruding said pre-mixture;
• converting said pre-mixture to granulate form or a melt;
• mixing said granulate or melt of the premixture with a granulate or a melt of a polymethyl methacrylate modified to be impact-resistant to form a plastic mixture wherein said polymethyl methacrylate comprises a polymer matrix and an agent to modify impact resistance;
• extruding or co-extruding the resultant plastic mixture with a melt of a thermoplastic plastic into an extrudate having a desired shape;
• and
• cooling said extrudate.