| 摘要 |
PCT No. PCT/EP93/01957 Sec. 371 Date Jan. 27, 1995 Sec. 102(e) Date Jan. 27, 1995 PCT Filed Jul. 22, 1993 PCT Pub. No. WO94/03532 PCT Pub. Date Feb. 17, 1994The present invention relates to hard polyurethane foams. These foams are produced by the reaction of 1) polyisocyanates, with 2) compounds having molecular weights of from 92 to 10,000 and having at least two hydrogen atoms which are reactive with isocyanate groups, in the presence of 3) hydrofluoroalkanes as foaming agents, and 4) solubilizers. Suitable solubilizers comprise one or more of R1OCOOR2; a) R2OCOOCOOR2; or <IMAGE> wherein R1 and R2 signify C1-C12-alkyl or together C2-C6-alkylene and n signifies an integer from 0 to 6;lkyl which is optionally substituted by halogens, C5-C10-cycloalkyl or optionally substituted aryl; lkyl or C5-C10-cycloalkyl; and/or <IMAGE> d) wherein R signifies C1-C20 alkyl or C5-C10 cycloalkyl. |
