公开(公告)号：US09952524B2

公开(公告)日：2018-04-24

申请号：US14404543

申请日：2013-05-30

Applicant: TODA KOGYO CORP.

Inventor： Kaori Kinoshita ,  Eiichi Kurita

IPC: G03G9/113 ,  G03G9/107 ,  G03G9/10

CPC classification number: G03G9/1135 ,  G03G9/10 ,  G03G9/107 ,  G03G9/1075 ,  G03G9/1131 ,  G03G9/1133 ,  G03G9/1136

Abstract: The present invention relates to a magnetic carrier for an electrophotographic developer comprising spherical composite core particles comprising at least ferromagnetic iron oxide fine particles and a cured phenol resin, and having an average particle diameter of 20 to 60 μm, the magnetic carrier for an electrophotographic developer satisfying the formula (1): σ1−σ0=−2 to 0 wherein σ0 represents a saturation magnetization (Am2/kg) of the carrier particles having a particle diameter in the vicinity of the average particle diameter of the magnetic carrier for an electrophotographic developer; and σ1 represents a saturation magnetization (Am2/kg) of the carrier particles having a particle diameter of less than 20 μm, and a two-component system developer using the magnetic carrier. The two-component system developer of the present invention includes a magnetic carrier used for an electrophotographic developer which can exhibit a good durability, is free from occurrence of carrier adhesion, and can maintain a high quality of images produced for a long period of time, and comprises the magnetic carrier for an electrophotographic developer and a toner.

公开(公告)号：US20150192874A1

公开(公告)日：2015-07-09

申请号：US14404543

申请日：2013-05-30

Applicant: TODA KOGYO CORP.

Inventor： Kaori Kinoshita ,  Eiichi Kurita

IPC: G03G9/107

CPC classification number: G03G9/1135 ,  G03G9/10 ,  G03G9/107 ,  G03G9/1075 ,  G03G9/1131 ,  G03G9/1133 ,  G03G9/1136

Abstract: The present invention relates to a magnetic carrier for an electrophotographic developer comprising spherical composite core particles comprising at least ferromagnetic iron oxide fine particles and a cured phenol resin, and having an average particle diameter of 20 to 60 μm, the magnetic carrier for an electrophotographic developer satisfying the formula (1): σ1−σ0=−2 to 0 wherein σ0 represents a saturation magnetization (Am2/kg) of the carrier particles having a particle diameter in the vicinity of the average particle diameter of the magnetic carrier for an electrophotographic developer; and σ1 represents a saturation magnetization (Am2/kg) of the carrier particles having a particle diameter of less than 20 μm, and a two-component system developer using the magnetic carrier. The two-component system developer of the present invention includes a magnetic carrier used for an electrophotographic developer which can exhibit a good durability, is free from occurrence of carrier adhesion, and can maintain a high quality of images produced for a long period of time, and comprises the magnetic carrier for an electrophotographic developer and a toner.

Abstract translation: 本发明涉及一种用于电子照相显影剂的磁性载体，其包含至少包含铁磁性氧化铁细颗粒和固化酚醛树脂的平均粒径为20至60μm的球形复合芯颗粒，用于电子照相显影剂的磁性载体 满足公式（1）：＆sgr; 1-＆sgr; 0 = -2至0其中＆sgr; 0表示粒径在平均粒径附近的载体颗粒的饱和磁化强度（Am2 / kg） 用于电子照相显影剂的磁性载体; ＆lt; sgr 1表示粒径小于20μm的载体颗粒的饱和磁化强度（Am2 / kg）和使用该磁性载体的双组分系统显影剂。 本发明的双组分系统显影剂包括用于电子照相显影剂的磁性载体，其能够表现出良好的耐久性，不会发生载体粘附，并且可以保持长时间产生的高质量图像， 并且包括用于电子照相显影剂的磁性载体和调色剂。