The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 27, 1994
Filed:
Mar. 23, 1990
Rainer Welte, Leverkusen, DE;
Hans J Scholl, Cologne, DE;
Bayer Aktiengesellschaft, Leverkusen, DE;
Abstract
The present invention relates to a process for the preparation of substantially closed-cell rigid foams containing urethane, urea, biuret, and isocyanurate groups comprising reacting, at an index of greater than 110, organic polyisocyanates with relatively high molecular weight polyots consisting of mixtures of (i) polyesters containing at least two hydroxyl groups and having an OH value of greater than 150 and/or polyethers containing at least two hydroxyl groups and having an OH value of greater than 200, and (ii) polyoxyalkylene polyethers containing ethylene oxide residues and least two hydroxyl groups and having an OH value of less than 100, in the presence of isocyanate trimerization catalysts and water as blowing agent. The foams of the invention can optionally be prepared optionally, in the further presence chain-extending and/or crosslinking agents and auxiliaries. and/or additives. The present invention also relates to a method using the foams of the invention as insulating materials and/or for reinforcing mechanical structural components.