Patent ID: 7169824
Filing Date: 2007-01-30
Classification: C08G

Abstract:
1. A process for preparing a flexible polyurethane foam having an apparent overall density of 15–150 kg/m 3 comprising reacting in a mould a polyisocyanate and an isocyanate-reactive composition in the presence of water, wherein the reaction is conducted at an isocyanate index of 40 to 120, the polyisocyanate comprising: a) 80–100% by weight of a diphenylmethane diisocyanate comprising at least 40% by weight of 4,4′-diphenylmethane diisocyanate and/or a variant of said diphenylmethane diisocyanate which variant is liquid at 25° C. and has an NCO value of at least 5% by weight, and b) 20–0% by weight of another polyisocyanate, and the isocyanate-reactive composition comprising: a) 70–100% by weight of a polyether polyol having an average nominal functionality of 2–8, an average equivalent weight of 750–5000, an average molecular weight of 2000–12000, an oxyethylene content of 60–90% by weight and a primary hydroxyl content of 70–100% calculated on the number of primary and secondary hydroxyl groups in the polyol, and b) 30–0% by weight of one or more other isocyanate-reactive compounds not being water.