摘要 |
PCT No. PCT/EP92/01183 Sec. 371 Date Dec. 3, 1993 Sec. 102(e) Date Dec. 3, 1993 PCT Filed May 26, 1992 PCT Pub. No. WO92/21910 PCT Pub. Date Dec. 10, 1992.For insulating pipes by application of at least one insulating layer and at least one outer surface layer by rotational molding, a rigid polyurethane foam is used as the insulating layer while a solid polyurethane is used as the surface layer. |