公开(公告)号：US09921510B2

公开(公告)日：2018-03-20

申请号：US15434300

申请日：2017-02-16

Applicant: TODA KOGYO CORPORATION

Inventor： Katsuji Iwami ,  Shigenori Harada ,  Eiichi Kurita ,  Kaori Kinoshita

IPC: G03G9/107 ,  G03G9/113 ,  G03G9/08 ,  G03G9/087 ,  G03G9/09

CPC classification number: G03G9/1075 ,  G03G9/0819 ,  G03G9/0827 ,  G03G9/08755 ,  G03G9/0918 ,  G03G9/107 ,  G03G9/1131 ,  G03G9/1133 ,  G03G9/1134 ,  G03G9/1135 ,  G03G9/1136

Abstract: The present invention relates to a magnetic carrier for an electrophotographic developer comprising spherical magnetic composite particles comprising a phenol resin as a binder and ferromagnetic iron oxide particles bonded to each other through the phenol resin, wherein the spherical magnetic composite particles have a ten-point mean roughness Rz of 0.3 to 2.0 μm. The magnetic carrier for an electrophotographic developer according to the present invention exhibits an excellent durability against peeling-off and abrasion of coating resins formed thereon and a high stability to mechanical stress exerted onto the carrier, is free from occurrence of spent toner, can be stably held over a long period of time without occurrence of fogging and unevenness in density of toner images, and can keep high-quality images with an excellent gradation for a long period of time.