| 摘要 |
PURPOSE:To obtain the molded form of hard urethane foam with the skin without producing any void while conserving energy by a method wherein an expanding molding is effected regulating the pressure in a mold, the pack rate of stock solution and an expanding temperature within a specified range. CONSTITUTION:The mold having airtightness is employed to evacuate the interior of the mold to 50-500mm.Hg and the stock solution of the hard urethane foam is poured into the mold at a pack rate of 150-450%, subsequently, it is expanded under keeping the temperature of the mold at 10-45 deg.C. Organic polyisocyanate, polyole, a catalyst, an expanding agent and foam regulating agent, further, a fire retardant, a pigment, a stabilizing agent or the like, if necessary, are contained in the stock solution of the hard urethane foam to be used. The pack rate is defined by a formula; pack rate (%)=the weight of the stock solution spent for obtaining the hard urethane foam molded form with the skin / the weight of the stock solution of the hard urethane foam necessary for filling the interior of the mold perfectly X100. |
