| 摘要 |
PROBLEM TO BE SOLVED: To provide a molded rigid polyurethane foam having a reduced thermal conductivity at densities between 33 to 38 kg/m, and applied to electric appliances, and a method for producing such foam.SOLUTION: A molded rigid polyurethane foam has a 1.65 to 2.15 ratio of applied foam density (kg/m) to lambda (mW/mK) measured at 10°C at 24 hours after the production of the foam, and is obtained by a process of injecting a reaction mixture at 1.1 to 1.9 packing factor under a reduced pressure into a hermetically closed mold cavity, and the reaction mixture includes (A) an organic polyisocyanate, (B) a physical blowing agent, (C) a polyol composition including at least one polyol having ≥3 functionalities and 200 to 800 hydroxy number and 0 to 2.5 wt.% water content based on the total amount of polyol composition, (D) a catalyst, and (E) an auxiliary substance and/or an additive. |
