| 摘要 |
PURPOSE:To obtain an expanded heat insulating material, capable of applying a low-pollution hydrochlorofluorocarbon as a foaming agent and having uniform fine cells without any froth voids, etc., by using a specific polyol component and a very small amount of a perfluoroalkane. CONSTITUTION:The material is obtained by mixing and stirring (A) an organic polyisocyanate with (B) a polyol component containing at least 5-25% hydroxyl group component of the formula (n is >=2) (e.g. diethylene glycol), (C) a foam stabilizer (e.g. a silicone-based surfactant), (D) a catalyst, (E) a foaming agent containing a hydrochlorofluorocarbon having -50 to 0 deg.C boiling point, (e.g. chlorodifluoromethane) as a component and (F) a 4-7C perfluoroalkane (e.g. perfluoropentane) in an amount of 0.1-5 pts.wt. based on 100 pts.wt. component (B). |
