Two-colored molded product of polyurethanes made by RIM and process for manufacturing the same

摘要

A small amount of a non-yellowing surface-forming polyurethane material containing a polyether polyol, a hexamethylene diisocyanate trimer, a coloring agent and an organic bismuth catalyst is initially injected into a mold cavity under reduced pressure to form e.g. the surface portion of a polyurethane covering for a steering wheel. An inner-forming polyurethane material is subsequently injected into the cavity under reduced pressure to form an inner portion of the covering.