| abstract |
(57) [Summary] [Structure] Water and a hydrocarbon are used as a foaming agent, and a) a polyether polyol obtained by adding propylene oxide to sucrose as a polyol component, b) an aromatic carboxylic acid or the same. A rigid polyurethane foam is produced using a polyester mixture obtained by polycondensation of an anhydride and a polyhydric alcohol, and c) a polyol mixture containing a polyether polyol obtained by adding propylene oxide to propylene glycol. [Effect] A rigid polyurethane foam excellent in thermal conductivity and foam fluidity can be obtained by using a hydrocarbon-based foaming agent that does not damage the ozone layer. |