A method for the production of fluorochlorohydrocarbon free, low density polyurethane - flexible foams and soft elastic polyurethane - moulded foams, as well as in this case, which can be used for example, with urethane groups modified diphenylmethane diisocyanate - based on polyisocyanate mixtures

摘要

items of the invention are a process for the production of cfc free polyurethane soft foams with low density (form) through implementation of $(a) liquid, urethangruppen containing bound polyisocyanatmischungen containing nco groups from 22 to 30%.-%, which, in turn, are produced by implementing a mixture of diphenylmethan - diisocyanaten and polyphenyl - polymethylen - polyisocyanaten (crude mdi) with at least one polyoxypropylene polyoxyethylene polyol with a functionality of 2.5 to 3.5, a hydroxylzahl from 50 to 90 and a m and containing polymerisierten ethylenoxidgruppen of more than 30 and less than 50%.-%, relative to the weight of polymerisierten ethylene oxide and 1,2 - propylenoxidgruppen or by application of 4,4 '- diphenylmethan - diisocyanates (mdi) or mdi isomer mixture with a polyoxypropylene polyoxyethylene polyol referred to an nco group containing quasipru00e4polymeren and dil this quasipru00e4polymeren u00fcnnung with crude mdi,with $a (b) hu00f6hermolekularen polyhydroxylverbindungen and, where appropriate, $a (c) low molecular weight kettenverlu00e4ngerungs and / or vernetzungsmitteln $a $a (d) in the presence of propellant, $a (e) catalysts and, where appropriate, $a (f) tools and / or additives, $a and erfindungsgemu00e4u00df type products with urethangruppen modified polyisocyanatmischungen (a).