| 摘要 |
PURPOSE:When a porous sheet is produced in a known manner, a specific modified surfactant is added to the polyurethane elastomer to give a porous sheet of high bleeding resistance and flexibility. CONSTITUTION:When a porous sheet is produced by coating a nonwoven fabric with a polyurethane elastomer, the solution of a polyurethane elastomer in an organic solvent is combined with 0.1-20 wt%, on the solid basis, of a modified surface active agent which prepared by bonding a nonionic surfactant, e.g., a polypropylene glycol-polyethylene glycol block copolyether of 1,000-20,000 molecular weight and 10-70wt% ethylene oxide chain content with less than 14 HLB, through an organic diisocyanate to both chain terminals of the polyol with the same composition as the polyol constituting the said polyurethane elastomer such as polyethylene ether glycol is used to coat a nonwoven fabric of natural or synthetic fibers therewith.
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