| abstract |
(57) [Abstract] (with correction) [PROBLEMS] A flexible polyurethane slab foam having a soft surface feel, supportability, durability, and flame retardancy. [MEANS FOR SOLVING PROBLEMS] Contains 20 to 50% by mass of 2,4'-isomer. NCO content 2 obtained by reacting MD, polymethylene polyphenyl polyisocyanate having three or more benzene rings, and polyoxyalkylene polyol having 2 to 4 functional groups and an average hydroxyl equivalent of 200 to 2,500. 3 to 33% by mass of a prepolymer, wherein the prepolymer is a urethane-modified polyisocyanate having an average number of functional groups of 2.00 to 2.25, and the polyol has a nominal number of functional groups of 2 to 4 and an average hydroxyl equivalent of 1 000 ~ A polyoxypropylene polyol having a terminal ethylene oxide cap of 2,500 and a polyoxyalkylene polyol having 2 to 6 functional groups in which oxyethylene in the oxyalkylene is 50% by mass or more and an average hydroxyl equivalent of 200 to 2,000 are used. |