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:
Oct. 12, 1993
Filed:
Jul. 16, 1991
Agfa-Gevaert, N.V., Mortsel, BE;
Abstract
Method of preparing solvent-resistant polymer beads sizing 0.5-5 pm and having a glass transition temperature of at least 40.degree. C. by dissolving in a solvent mixture of water and water-miscible polar organic solvent an Alpha, Beta-ethylenically unsaturated monomer (1) capable of forming a polymer that is soluble in the monomer(s) present in said solvent mixture but which is insoluble in said solvent mixture, a monomer (2) carrying COOH group(s), a monomer (3) carrying halogen atom(s), a free radical-forming polymerization initiator, and a graft-polymerizable polymer containing hydrophilic groups, heating the solution obtained to a temperature from 50.degree. C. to the reflux temperature thereof with stirring to form said beads, converting said COOH group(s) by reaction with a hydroxide into a carboxylic acid salt group, and causing said carboxylic acid salt group to react with said halogen atom to form ester cross-linkages. The beads can be used as spacing agents in a sheet or web material.