Ferrite carrier for electrophotographic developer and electrophotographic developer
AssigneePowdertech Co., Ltd.
InventorsHiromichi Kobayashi, Takao Sugiura, Kanao Kayamoto
Life of this patent
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Abstract
Disclosed are a ferrite carrier for electrophotographic developer and an electrophotographic developer using the ferrite carrier, wherein: the ferrite carrier is a composite ferrite composed of Li and Mg; when the composition of the ferrite is calculated as a mixture of a Li ferrite having a stoichiometric composition and a Mg ferrite having a stoichiometric composition, the excessive amount of Fe2O3 is less than 5 mol %, or the total excessive amount of Li2O and MgO is less than 1 mol %; the content of the elements other than Li, Mg, Fe and O is 2 % by weight or less; and further, the content of Mn in terms of element is 1000 to 9000 ppm.
Claims6
A ferrite carrier for electrophotographic developer wherein:
- the ferrite carrier is a composite ferrite comprising Li and Mg;
- when the composition of the ferrite is calculated as a mixture of a Li ferrite having a stoichiometric composition and a Mg ferrite having a stoichiometric composition, the excessive amount of Fe2O3 is less than 5 mol %, or the total excessive amount of Li2O and MgO is less than 1 mol %;
- the content of the elements other than Li, Mg, Fe and O is 2% by weight or less;
- and
- further, the content of Mn in terms of element is 1000 to 9000 ppm.
Dependencies are inferred from the claim text.