| 摘要 |
PROBLEM TO BE SOLVED: To provide a preparing process in which a polyurethane foam having an excellent surface state and a low density can be demolded in a short period of time. SOLUTION: In this preparing process of the polyurethane foam, the polyurethane foam having a fine cell of a density of 0.2-0.8 g/cm<SP>3</SP>is prepared by a reaction injection molding process from a polyisocyanate and a polyol mixture comprising a polyol, a catalyst, a foaming agent, and optionally a crosslinking agent, an internal mold release agent, a reinforcing agent and other auxiliary substances. (1) The foaming agent is 0.4-2 pts.wt. of formic acid against 100 pts.wt. of the polyol mixture. (2) Water as a foaming agent is not added. (3) The water content in the polyol mixture is not more than 0.4 wt.%. COPYRIGHT: (C)2005,JPO&NCIPI |
