METHOD FOR MANUFACTURING HEAT INSULATING PANEL

摘要

PROBLEM TO BE SOLVED: To provide a method for manufacturing a heat insulating panel which is free from the triggering of environmental destruction because of the non-use of a chlorofluorocarbon as a foaming agent and is of high strength and not brittle and further, can be securely bonded to a surface material. SOLUTION: A polyisocyanate mixture 1 is prepared by blending a trimerization catalyst of a polyisocyanate, a polyol and an isocyanate with pentane as the foaming agent. The heat insulating, material 4 is obtained by supplying the polyisocyanate mixture 1 to the surface of the surface material 2 and expanding the former.