Thermoformable film with embossed grain surface structure, in particular for automotive internal parts, is continuously hardened in local areas to be stretched further during thermoforming

摘要

Continuous hardening of the surface structure(2) in localized areas(3) of the film(1) which are to be subjected to a higher degree of stretching during a subsequent thermoforming operation gives more uniform structure stretching in these areas. Local areas(3) are hardened with high energy source such as a laser or electron beam. Heat from the beam either produces a cross-linking effect or reduces the plasticizer content in the high stretch areas. Hardening may be varied according to the degree of intended extension. Hardened areas may radiate ray-like(4) from a central point(5). An independent claim is included for a method of forming the thermoformable film in which the film(1) is continuously hardened in the peaks and valleys of the surface structure in localized areas subjected to higher extension.