| 摘要 |
PROBLEM TO BE SOLVED: To provide a polyisocyanate composition having a good storing stability, for producing a hard polyurethane foam having an excellent foaming efficiency, storing stability, forming property, foam strength, dimensional stability, adhesion property, etc., and a method for producing the hard polyurethane foam by using the above composition. SOLUTION: This polyisocyanate composition for the hard polyurethane foam consists of an isocyanate terminal prepolymer (A1) obtained by reacting (a1) a polymeric MDI with (a2) a polyether containing hydroxyl group in (a1):(a2)=(80:20)-(99.9:0.1) mass ratio, and the method for producing the hard polyurethane foam is also provided. The hydroxyl-group containing polyether (a2) is characterized by having (a) 150-10,000 number-average molecular weight and (b) a >=3C mono-valent organic group at its terminals, and containing (c) >=70 mass % oxypropylene group. |
