Process for producing rigid polyurethane foams

US5578651A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Wilhelm Lamberts · Cologne, DE
• Norbert Eisen · Hanerau-Hademarschen, DE

Key dates

• Filing date: Jan 27, 1995
• Grant date: Nov 26, 1996
• Expiry date: Jan 27, 2015

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08J2375/04
• WIPO field: Other special machines
• WIPO sector: Mechanical engineering

Abstract

The present invention relates to hard polyurethane foams. These foams are produced by the reaction of 1) polyisocyanates, with 2) compounds having molecular weights of from 92 to 10,000 and having at least two hydrogen atoms which are reactive with isocyanate groups, in the presence of 3) hydrofluoroalkanes as foaming agents, and 4) solubilizers. Suitable solubilizers comprise one or more of ##STR1## wherein R.sup.1 and R.sup.2 signify C.sub.1 -C.sub.12 -alkyl or together C.sub.2 -C.sub.6 -alkylene and n signifies an integer from 0 to 6; ##STR2## wherein R.sup.1 to R.sup.3 signify C.sub.1 -C.sub.12 -alkyl which is optionally substituted by halogens, C.sub.5 -C.sub.10 -cycloalkyl or optionally substituted aryl; ##STR3## wherein R.sup.1 and R.sup.2 signify C.sub.1 -C.sub.16 -alkyl or C.sub.5 -C.sub.10 -cycloalkyl; and/or ##STR4## wherein R signifies C.sub.1 -C.sub.20 alkyl or C.sub.5 -C.sub.10 cycloalkyl.