PHENOLIC RESIN FOAM

摘要

A phenolic resin foam characterized by having a proportion of closed cells of 70 % or above, a mean cell diameter of 10 to 400 mu m and a density of 10 to 70 kg/m<3>, containing a hydrofluorocarbon in the closed cells, and being made of a phenolic resin having a urea-cross-linked structure. By virtue of the specific cross-linking density and the urea-cross-linked structure, this foam exhibits excellent heat insulating performance and is improved in mechanical strengths and surface brittleness, though HFC is used as the blowing agent.