Process for the production of cold setting foams which contain urethane groups prepared from a mixture of 4,4-diphenyl methane diisocyanate and 2,4-diphenyl methane diisocyanate

US4256849A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Jurgen Ick · Dorpsstraat, US
• Hans-Joachim Meiners · Leverkusen, DE
• Gunter Oertel · Leverkusen, DE
• Gunter Hauptmann · Odenthal, DE
• Klaus Konig · Leverkusen, DE

Key dates

• Filing date: Dec 14, 1979
• Grant date: Mar 17, 1981
• Expiry date: Dec 14, 1999

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08G2110/0058
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

The instant invention is directed to a process for the production of cold setting, flexible foams which contain urethane groups by the reaction of polyethers with a molecular weight of 400 to 10,000 which contain at least two hydroxyl groups and in which at least 10% by weight of the hydroxyl groups are primary hydroxyl groups, with a mixture of diphenyl methane diisocyanates and oligomeric polyphenyl-polymethylene polyisocyanates in the presence of blowing agents and optionally in the presence of catalysts and other foaming aids, the improvement wherein the mixture of diphenyl methane diisocyanates and polyphenyl-polymethylene polyisocyanate mixtures is substantially free of carbodiimide groups, has an isocyanate content greater than 30%, and contains from 60 to 90% by weight of 4,4' diphenyl methane diisocyanate and from 3 to 30% by weight of 2,4' diphenyl methane diisocyanate.