Patent · US Expired

Process for the preparation of polyurethane foams

US4931480A · kind A · utility

2Cited by

1References

4Claims

0Family size

Assignee

BAYER HEALTHCARE LLC · DE

Inventors

Kurt Krippl · Monheim, DE
Klaus Schulte · Mölnbo, SE
Erwin Hoffmann · Leverkusen, DE
Rolf Wiedermann · Bensberg, DE

Key dates

Filing date	Feb 27, 1989
Grant date	Jun 5, 1990
Priority date	—
Expiry date	Feb 27, 2009

Classification

Technology area (CPC C)Chemistry; Metallurgy
CPC primaryC08J2375/04
WIPO fieldOther special machines
WIPO sectorMechanical engineering

Abstract

This invention relates to a process for the preparation of polyurethane foams by the reaction of a foamable reaction mixture. A liquid blowing agent is added to either the isocyanate or the polyol prior to mixing of the components. An inert gas is dispersed in the component which contains the blowing agent and the gas charged component is immediately and continuously mixed with the other component, at the same time keeping it at least under the pressure required for charging it with gas until mixing has been completed, and leaving the resulting reaction mixture to foam up. The key to the present invention is in the small amount of gas charging.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.