| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for spraying hard polyurethane foam on-site and a heat insulating structure, such that excellent construction properties and heat insulating performance are provided, without troubles with foam molding even if construction work is done at low temperatures, by using no fluorocarbon type foaming agents at all or using a small amount of alternate fluorocarbon. SOLUTION: An auxiliary heat insulating layer 2, made of hard polyurethane foam containing an alternate fluorocarbon which can be foamed on-site, or other sprayed heat insulating material that is less prone to be influenced of low temperatures, is first formed on the surface of a concrete wall main body 1. Next, an isocyanate composition and a polyol composition are sprayed to the surface of the auxiliary heat insulating layer 2 and foamed in the presence of water or a foaming agent comprises a non-fluorocarbon compound, and a catalyst, etc., to form a main heat insulating layer 3 of non-fluorocarbon hard polyurethane foam. An incombustible cover material, normally mortar and the like, is sprayed over the main heat insulating layer 3 as a sealing layer 4. |
