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:
Dec. 21, 1999
Filed:
Mar. 04, 1997
Ulrich Desor, Idstein, DE;
Stephan Krieger, Hofheim, DE;
Clariant GmbH, Frankfurt, DE;
Abstract
A polymer dispersion having a minimum film-forming temperature in the range from 0 to 40.degree. C., which is useful in coating compositions for substrates, in the form of varnishes or gloss paints, is obtained by stepwise emulsion polymerization, which includes polymerizing, onto a first stage having the monomer composition I comprising: from 50 to 68.5% by weight of soft monomers A whose homopolymers have a glass transition temperature (T.sub.g) below 0.degree. C.; from 30 to 50% by weight of hard monomers B whose homopolymers have a glass transition temperature (T.sub.g) above 65.degree. C.; from 0.5 to 5% by weight of .alpha.,.beta.-unsaturated carboxylic acids and/or carboxamides C which are copolymerizable with A and B; from 1 to 7.5% by weight of ethylenically unsaturated monomers D containing keto groups; and from 0 to 10% by weight of other ethylenically unsaturated monomers E which do not contain a nitrogen atom, where the weight percentages in each case are based on the overall amount of the polymer of the first stage, a second stage having the monomer composition II comprising: from 5 to 45% by weight of soft monomers A whose homopolymers have a glass transition temperature (T.sub.g) below 0.degree. C.; from 65 to 95% by weight of hard monomers B whose homopolymers have a glass transition temperature (T.sub.g) above 65.degree. C.; from 0 to 4% by weight of .alpha.,.beta.-unsaturated carboxylic acids and/or carboxamides C which are copolymerizable with A and B; from 0 to 5% by weight of ethylenically unsaturated monomers D containing keto groups; and from 0 to 10% by weight of other ethylenically unsaturated monomers E which do not contain a nitrogen atom, where the weight percentages in each case are based on the overall amount of the polymer of the second stage, in a weight ratio of the monomer composition I to the monomer composition II of from 50:50 to 75:25.