MANUFACTURING METHOD FOR SOFT POLYURETHANE FOAM

摘要

A manufacturing method for a soft polyurethane foam, wherein a polyol composition (I) and a polyisocyanate compound (II) are reacted in the presence of a foaming agent, a foam stabilizer, a crosslinking agent with a melting point of 40-270°C that has a group capable of reacting with an isocyanate group, and a urethane-forming catalyst comprising a tin(II) catalyst. The polyol composition (I) comprises: a polyol (A) of which the average number of hydroxyl groups is 2-3, the average hydroxyl group value is 5-90 mg KOH/g, and the oxyethylene group content is 30 mass% or less of the entire oxyalkylene group (100 mass%); a polyol (B) of which the average number of hydroxyl groups is 2-3, and the average hydroxyl group value is 100-250 mg KOH/g; and a mono-ol (D) of which the average hydroxyl group value is 10-200 mg KOH/g. Dibutyltin dilaurate is not employed as the urethane-forming catalyst, foam height loss does not occur after foam formation when the tin(II) catalyst is used, and the soft polyurethane foam yielded by the manufacturing method has low density and exhibits excellent low-resilience properties, body pressure dispersion properties, and durability.