| 摘要 |
PROBLEM TO BE SOLVED: To prepare a heat insulating gas composed of a five-membered cyclic ether compound having H, F, C and O atoms with proviso that the numbers of H and O atoms are specified, hardly affecting the global environment and having a higher heat-insulating property than conventional gases. SOLUTION: The objective heat insulating gas is composed of a five- membered cyclic ether compound having H, F, C and O atoms with proviso that the numbers of H and O atoms are 1-2 and 1-2, respectively and preferably composed of a cyclic ether of -CF2CF2CF2CHFO-, -CHFCF2CF2CHFO- or -CF2 CF2OCH(CF3)O-. Rigid urethane foam can be produced by mixing the heat insulating gas as a blowing agent with a polyol, a polyisocyanate, a catalyst, water, a surfactant and a foam stabilizer, followed by reaction. |
