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:
Jul. 18, 2000
Filed:
May. 25, 1999
Applicant:
Inventors:
Frank Richter, Leverkusen, DE;
Eberhard Stelter, Koln, DE;
Wilfried Litz, Koln, DE;
Stefan Groth, Leverkusen, DE;
Assignee:
Bayer Aktiengesellschaft, Leverkusen, DE;
Attorneys:
Primary Examiner:
Int. Cl.
CPC ...
C07D / ; C07D / ; C08G / ; C08G / ; C08G / ;
U.S. Cl.
CPC ...
544 67 ; 528 51 ; 528 67 ; 528 73 ; 528 74 ; 544 68 ; 544193 ; 544222 ;
Abstract
The present invention relates to a process for the preparation of trimerized polyisocyanates that contain at least 30 mole % of iminooxadiazinedione groups (asymmetric trimers) in the trimer mixture, by catalytically trimerizing a starting isocyanate selected from organic di- or polyisocyanates having a number average molecular weight of 140 to 600 and containing aliphatically, cycloaliphatically and/or araliphatically bound isocyanate groups in the presence of a quaternary phosphonium polyfluoride trimerization catalyst corresponding to the formula