| 摘要 |
PROBLEM TO BE SOLVED: To provide a production method of an open cell rigid foamed synthetic resin of which raw materials has an excellent storage stability of and which has an excellent dimensional stability without generating sink-marks even if a large quantities of water is used as a foaming agent. SOLUTION: The production method of the rigid foamed synthetic resin comprises reacting (A) 25-60 mass% of a polyethyer polyol having an average hydroxyl group value of 300-600 mg KOH/g which is made by adding ethylene oxide or the ethylene oxide and an alkylene oxide of >=3C to sorbitol of an initiator, and contains contents of >=30 mass% of a construction unit based on the ethylene oxide, (B) 40-75 mass% of a polyol containing 10-55 mass% of the polyether polyol using a cyclic amine as an initiator, the polyol having an average hydroxyl group number of <=4 and the average hydroxyl group value of 200-600 mg KOH/g, and (C) a hydroxyl compound mixture containing 0-25 mass% of a polyether monool having the average hydroxyl group value of 20-700 mg KOH/g, the mixture being made by adding ethylene, propylene or both to an initiator, using the water as the foaming agent in the presence of a foam stabilizer and a catalyst. |
