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:
Sep. 28, 1999
Filed:
Jul. 25, 1997
Uwe Neumann, Mobile, AL (US);
Martin Gerlitz, Graz, AT;
Vianova Resins GmbH, Mainz-Kastel, DE;
Abstract
Water-dispersible curing agents for epoxy resins are disclosed which, as a mixture with epoxy resins, have a potlife indication by showing the end of the processing time by a clear increase in viscosity, and which comprise reaction products (ABC) of adducts of aliphatic polyols (A) with a weight-average molar mass of from 200 to 20, 000 g/mol, comprising at least one polyol (A1) having a molar mass of less than 4000 g/mol, and at least one polyol (A2) having a molar mass of more than 4000 g/mol, and at least one epoxide compound (B) having at least two epoxide groups per molecule, and a specific epoxide group content of from 500 to 10 000 mmol/kg, (A1) and (A2) being reacted separately or as a mixture with (B), and then reacting this adduct with one or more polyamines (C) having at least three amine hydrogen atoms and at least one primary amino group per molecule, the ratio of the number of hydroxyl groups of component (A) to the number of epoxide groups of component (B) being 1:3 to 1:10, and the ratio of the number of remaining epoxide groups in the epoxide-polyol adduct to the number of amine hydrogen atoms in polyamines (C) being 1:1.5 to 1:100. The water-dispersible curing agents are useful as curing agents for epoxy resins in two component coating compositions.