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:
Jun. 18, 2013
Filed:
Jul. 27, 2010
Hiroshi Yamauchi, Osaka, JP;
Yasuyuki Yamada, Osaka, JP;
Hiroshi Yamauchi, Osaka, JP;
Yasuyuki Yamada, Osaka, JP;
Sekisui Chemical Co., Ltd., Osaka, JP;
Abstract
Provided is a method for producing single-hole hollow polymer particles which have an extremely uniform outside diameter and inside diameter, and thus do not require a classifying operation. Further provided are single-hole hollow polymer particles produced by such a method for producing single-hole hollow polymer particles. The invention relates to a method for producing single-hole hollow polymer particles, which includes: preparing a dispersion of swollen particle droplets by mixing a seed particle dispersion obtained by dispersing uncrosslinked polymer-containing seed particles in a water-containing dispersion medium, with a radical polymerizable monomer, an oil-soluble solvent and an oil-soluble polymerization initiator, and causing the radical polymerizable monomer, the oil-soluble solvent and the oil-soluble polymerization initiator to be absorbed in the seed particles; and polymerizing the radical polymerizable monomer in the swollen particle droplets. The relationship between the SP value of a polymer obtained by polymerizing the radical polymerizable monomer (SPp) and the SP value of the oil-soluble solvent (SPs) satisfies formula (1) below:2.1≦≦7.0  (1).