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:
May. 23, 1995
Filed:
Jun. 10, 1991
Rainer Welte, Leverkusen, DE;
Hans-Joachim Scholl, Cologne, DE;
Bayer Aktiengesellschaft, Leverkusen, DE;
Abstract
Substantially closed-cell rigid foams containing urethane, urea and biuret groups are produced by reacting an NCO terminated prepolymer with a compound having at least two isocyanate-reactive hydrogen atoms and a molecular weight of from about 400 to about 10,000 in the presence of a catalyst and water by any of the known techniques. The NCO terminated prepolymer is the reaction product of x parts by weight of an at least difunctional polyol having an OH value of less than 100 with y parts by weight of an at least difunctional polyisocyanate. The ratio of x to y is at least 1:10. The product foams are particularly useful as insulating materials.