In a process for the production of a lightweight cold urethane wherein raw materials
are injected into a mold in one shot, diethanolamine is added in an amount of 0.1
to 2.0 parts by weight per 100 parts by weight of the polyol. When principal raw
materials including a polyol and an isocyanate, and an auxiliary ingredient mixture
prepared by previously mixing auxiliary ingredients other than the polyol and the
isocyanate, are injected into a mold from separate storage vessels, a water-soluble
silicone foam stabilizer is added to the auxiliary ingredient mixture.
