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:
Mar. 25, 1997
Filed:
Jun. 08, 1995
Georg Burkhart, Essen, DE;
Helmut Schator, Essen, DE;
Th. Goldschmidt AG., Essen, DE;
Abstract
A method is described for the preparation of rigid foams, having urethane and/or isocyanurate groups and being extensively open celled, by reacting polyisocyanates with compounds having at least two groups capable of reacting with isocyanates and the equivalent weight per reactive group of which is about 9 to 800, in the presence of catalysts, surface active substances, as well as, optionally, physical blowing agents, flame retardants and other known auxiliary materials and finishing agents, wherein the reaction is carried out in the presence of liquid, higher molecular weight, unsaturated hydrocarbons, which are free of groups capable of reacting with isocyanates, in amounts of 0.01 to 3.0% by weight, based on the reaction formulation. Particularly preferred hydrocarbons are polybutadiene and polyoctenylene with an average molecular weight of 800 to 10,000 g/mole. The rigid foams, because of their open cell nature, exhibit high dimensional stability.