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:
Jan. 13, 2015
Filed:
Dec. 17, 2012
Yoshitaka Yamauchi, Shizuoka, JP;
Masahide Yamada, Shizuoka, JP;
Yoshihiro Moriya, Shizuoka, JP;
Taichi Nemoto, Shizuoka, JP;
Yukiko Nakajima, Kanagawa, JP;
Keiji Makabe, Shizuoka, JP;
Daiki Yamashita, Kanagawa, JP;
Suzuka Amemori, Shizuoka, JP;
Akiyoshi Sabu, Shizuoka, JP;
Yoshitaka Yamauchi, Shizuoka, JP;
Masahide Yamada, Shizuoka, JP;
Yoshihiro Moriya, Shizuoka, JP;
Taichi Nemoto, Shizuoka, JP;
Yukiko Nakajima, Kanagawa, JP;
Keiji Makabe, Shizuoka, JP;
Daiki Yamashita, Kanagawa, JP;
Suzuka Amemori, Shizuoka, JP;
Akiyoshi Sabu, Shizuoka, JP;
Ricoh Company, Ltd., Tokyo, JP;
Abstract
The toner includes a pigment; and a block copolymer having a polyester block A including a residual group of a hydroxycarboxylic acid, and a polyester block B including an anionic group. When cross-section of the block copolymer is observed by a tapping mode atomic force microscope to obtain a phase image of the cross-section, the polyester block B, which has relatively large phase delay, is dispersed as domains having an average size of from 20 nm to 100 nm in a domain of the polyester block A, which has relatively small phase delay. The block copolymer has a first glass transition temperature of from −20° C. to 20° C., and a second glass transition temperature of from 35° C. to 65° C. when the first and second glass transition temperatures are determined from a thermogram obtained by subjecting the block copolymer to differential scanning calorimetry (DSC) at a temperature rising speed of 5° C./min.