Production of outer skin of low-density polyurethane which consists of expanded polyurethane layer and optional primer-polyurethane layer comprises injecting expanded polyurethane composition over mold surface optionally coated with primer

摘要

Production of an outer skin (12) of low-density polyurethane which consists of an expanded polyurethane layer and an optional primer-polyurethane layer comprises injecting an expanded polyurethane composition over the surface of a mold which is optionally coated with primer. The composition contains an isocyanate, a polyol and a blowing agent in an amount which produces an outer skin with a density of 0.3 - 0.75 g/cm 3>. It is used in an amount which produces a skin of thickness 0.5 - 3 mm. Independent claims are included for: (A) production of low density polyurethane for use in linings for the interiors of cars by producing a first layer using the described process and spraying a second layer of lower density on to the first while it is still in the mold, the isocyanate and polyol used being the same in both compositions; and (B) outer skins of low-density polyurethane comprising: (a) a first polyurethane layer which contains residues from reaction of a first isocyanate and a first polyol; and (b) a second polyurethane layer which contains residues from reaction of a second composition containing an isocyanate, a polyol and a blowing agent in an amount such that the outer skin has a density of 0.3 - 0.75 g/cm 3>.