| 摘要 |
PURPOSE:To obtain a rigid polyurethane foam excellent in dimensional stability and heat insulating properties by conducting a process for obtaining the foam by reacting a polyol with a polyisocyanate in the presence of a blowing agent, wherein specified compounds are used as the polyol and the blowing agent. CONSTITUTION:A process for obtaining the foam by reacting a polyol with a polyisocyanate (e.g. polymethylene polyphoenyl isocyanate) in the presence of a blowing agent, which process comprises at least an active hydrogen compound (alkylene oxide adduct) (e.g. sorbitol) is used as the polyol, and an H- containing halohydrocarbon (e.g. HCFC-141b) and/or water are used as the blowing agent, is provided. |
