Patent ID: 6037382
Filing Date: 2000-03-14
Classification: C08G,Y10S

Abstract:
A process for preparing a flexible polyurethane foam at an NCO index of 70-120 by reactinga) a polyisocyanate composition comprising per 100 parts by weight of the composition 5 to 20 parts by weight of tolylene diisocyanate and 80-95 parts by weight of diphenylmethane diisocyanate and homologues thereof having an isocyanate functionality of 3 or more, the amount of diphenylmethane diisocyanate being 70 to 95% by weight calculated on the amount of diphenylmethane diisocyanates and homologues, and the diphenylmethane diisocyanate comprising 8-45% by weight, calculated on the weight of this diphenylmethane diisocyanate, of diphenylmethane diisocyanate containing at least one NCO group in the ortho position,b) a polyol composition comprising1) a polyoxyethylene-polyoxypropylene-polyol, having an average nominal hydroxyl functionality of 2-6, an average equivalent weight of 1000-4000 and containing 5-25% by weight of oxyethyelene groups;2) 2 to 7 parts by weight of water;3) 2 to 10 parts by weight of a polyether polyol having an average nominal hydroxyl functionality of 2-6, an average equivalent weight of 200-1500 and containing at least 60% by weight of oxyethylene groups;4) 1 to 15 parts by weight of particulate material which is the reaction product of a polyisocyanate and a compound having a plurality of hydroxyl-, primary amine- and/or secondary amine groups and having an equivalent weight of up to 400 and which material is dispersed in said polyol composition; the amounts of b2) to b4) being calculated per 100 parts by weight of b1); and5) optionally auxiliaries and additives known per se.