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:
Jun. 19, 1990
Filed:
Apr. 26, 1989
Wolfgang Wellner, Bergisch Gladbach, DE;
Bayer Aktiengesellschaft, Bayerwerk, DE;
Abstract
The present invention is directed to a process for the production of urethane- or isocyanurate-modified polyisocyanates based on a starting diisocyanate selected from (i) 2,4-diisocyanatotoluene or mixtures thereof with up to about 35%, based on the mixture, of 2,6-diisocyanatotoluene, (ii) mixtures of the diisocyanates mentioned under (i) with up to 80 NCO equivalent %, based on the mixture, of 1,6-diisocyanatohexane and (iii) 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethyl cyclohexane by reacting the starting diisocyanate with substoichiometric quantities of polyhydric alcohols or trimerizing a portion of the isocyanate groups of the starting diisocyanate, removing sufficient excess, unreacted starting diisocyanate to obtain modified polyisocyanates containing at most 3% by weight, based on solids, of monomeric starting diisocyanate, characterized in that, the content of starting diisocyanate is further reduced by adding at least 10 mol-% water, based on the content of unreacted 2,4-diisocyanatotoluene or 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethyl cyclohexane present, to the modified polyisocyanates. The present invention is also directed to the low-monomer polyisocyanates obtained by this process and their use as the binder component in one-component or two-component polyurethane lacquers.