发明名称 |
Toner, developer including the toner, image forming apparatus using the toner, and block copolymer |
摘要 |
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. |
申请公布号 |
US8932790(B2) |
申请公布日期 |
2015.01.13 |
申请号 |
US201213716385 |
申请日期 |
2012.12.17 |
申请人 |
Ricoh Company, Ltd. |
发明人 |
Yamauchi Yoshitaka;Yamada Masahide;Moriya Yoshihiro;Nemoto Taichi;Nakajima Yukiko;Makabe Keiji;Yamashita Daiki;Amemori Suzuka;Sabu Akiyoshi |
分类号 |
G03G9/087;C08G63/91;G03G15/08;G03G9/08 |
主分类号 |
G03G9/087 |
代理机构 |
Oblon, Spivak, McClelland, Maier & Neustadt, L.L.P. |
代理人 |
Oblon, Spivak, McClelland, Maier & Neustadt, L.L.P. |
主权项 |
1. A block copolymer comprising
a polyester block A including a residual group of a hydroxycarboxylic acid; and a polyester block B including an anionic group, wherein the anionic group includes a group having a formula —SO3−, wherein the block copolymer has a configuration such that when a 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 domain size of from 20 nm to 100 nm in a domain of the polyester block A, which has relatively small phase delay, and wherein 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. |
地址 |
Tokyo JP |