公开(公告)号：US20200241435A1

公开(公告)日：2020-07-30

申请号：US16751031

申请日：2020-01-23

Applicant: POWDERTECH CO., LTD.

Inventor： Hiroki SAWAMOTO ,  Atsushi NII ,  Yuji ITO ,  Hajime AKIBA ,  Shinya HANYU

IPC: G03G9/107 ,  G03G9/08

Abstract: The present invention relates to a carrier core material for electrophotographic developer, having a ferrite composition and having a supernatant transmittance of 85.0% or more, a method for producing the carrier core material, a carrier for electrophotographic developer, containing the carrier core material, and a developer containing the carrier.

公开(公告)号：US20180074426A1

公开(公告)日：2018-03-15

申请号：US15696698

申请日：2017-09-06

Applicant: POWDERTECH CO., LTD.

Inventor： Hiroki SAWAMOTO ,  Hajime AKIBA ,  Tetsuya UEMURA

IPC: G03G9/113 ,  G03G9/107

CPC classification number: G03G9/1133 ,  G03G9/10 ,  G03G9/107 ,  G03G9/1075 ,  G03G9/1131 ,  G03G9/1132 ,  G03G9/1136

Abstract: An object of the present invention is to provide a carrier low in specific gravity and less in both environmental fluctuation and change of the charge amount after aging, an electrophotographic developer using the carrier, and a method of manufacturing the carrier. To achieve the object, the carrier is manufactured by coating a core material composed of a magnetic component and a non-magnetic component with a resin, and the carrier is characterized in that water content is 200 ppm or less and cyclic siloxane content is 100 ppb or less. Further, an electrophotographic developer containing the carrier is provided.