Reaction injection molding method.

摘要

@ A molded article is formed by a reaction injection molding method wherein a starting material, e.g., an ω-lactam, is injected into a mold the inner pressure of which is maintained at 0.5 to 20 kg/cm2·G with an inert gas; and the inner pressure of the mold is maintained at a level higher than the pressure increased by injection of the starting material until the polymerization molding of the starting material is completed.