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:
Jul. 03, 1990
Filed:
Mar. 28, 1988
Toppan Moore Co., Ltd., Tokyo, JP;
Abstract
Microcapsules are prepared by adding a methylolated melamine or methylolated urea to an aqueous emulsion of the core material dispersed in an aqueous solution of a styrene/maleic anhydride copolymer partially hydrolyzed in an alkaline condition and heating the mixture at 40.degree. to 90.degree. C. in an acidic condition so that a reaction product forming the capsule walls is produced by the esterification reaction between the carboxyl groups in the partial hydrolysis product and the methylol groups in the methylolated melamine or urea and the amidation reaction between the carboxylic anhydride groups in the former and the amino groups in the latter. By virtue of the three dimensional network structure, the capsule walls are very dense and highly resistant against heat, water and solvents.