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:
Mar. 03, 1992
Filed:
Mar. 26, 1991
Shoji Ito, Tsukuba, JP;
Okihiko Tlirasa, Tsukuba, JP;
Shouei Fujishige, Tsukuba, JP;
Aizo Yamauchi, Tsukuba, JP;
Agency of Industrial Science and Technology, Tokyo, JP;
Ministry of International Trade and Industry, Tokyo, JP;
Abstract
A dispersion containing minute polymer beads possessing a thermosensitive characteristic is produced by a method which comprises preparing an aqueous solution of an acrylamide type vinyl compound, the homopolymer of which exhibits a hydrophilicity-hydrophobicity thermoreversible solubility characteristic, adding a cationic or anionic surfactant in a ratio equaling or exceeding the micelle concentration to the aqueous solution, adjusting the resultant aqueous solution to a temperature not lower than the clouding point thereof and, at the same time, polymerizing the acrylamide type vinyl compound in the aqueous solution thereby forming a polymer emulsion, exposing the emulsion to an ionizing radiation thereby cross-linking minute polymer beads in the emulsion, and thereafter depriving the resultant polymer emulsion of the surfactant.