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:
Jan. 27, 1987
Filed:
May. 03, 1985
Hanns P Muller, Odenthal, DE;
Werner Clarenz, Leverkusen, DE;
Ulrich von Gizycki, Leverkusen, DE;
Kuno Wagner, Leverkusen, DE;
Bayer Aktiengesellschaft, Bayerwerk, DE;
Abstract
The present invention relates to substantially colorless organic polyisocyanates, optionally in solution in an inert solvent, having a Hazen color index according to DIN 53 409 of at most 60 and a yellow value according to DIN 6167 of at most 3.0, characterized by a content of about 0.01 to 1 ppm (by weight), based on polyisocyanate, of an organic dye soluble in the polyisocyanate and having an absorption maximum of about 560 to 590 nm or a mixture of such dyes. The present invention also relates to two processes for preparing the substantially colorless organic polyisocyanates. In the first process, the organic dye is added to the prepared polyisocyanate while in the second process the organic dye is added to the starting materials used to prepare the polyisocyanate. Finally, the present invention is directed to the production of polyisocyanate polyaddition products from the substantially colorless organic polyisocyanates and isocyanate-reactive compounds.