PURPOSE: To improve durability by thermally oxidizing a mixture of zinc ferrite and Fe3O4 to allow it to have a specified proportion of iron ions and incorporating a magnetic mixture of the obtained magnetic material and α-Fe2O3 in a binder resin in a specified amt.
CONSTITUTION: Hundred pts.wt. of a binder resin contain 20W100pts.wt. of magnetic mixture of α-Fe2O3 and a magnetic material obtained by subjecting a mixture of 7W50mol% zinc ferrite composed of (ZnO)x(FeO)1-xFe2O3 (x=1.00W 0.90) and 93W50mol% Fe3O4 to thermal oxidation treatment to convert the constituent atomic ratio of iron into Fe3+/(Fe3++Fe2+)≥0.95. The toner using this magnetic material has high lightness as compared with a sepia colored toner using only α-Fe2O3 magnetic material, and it can form an image high in density. Said obtained magnetic material is made extremely stable against light and heat by heat oxidizing Fe3O4 and ZnOFe2O3 and blending α-Fe2O3 to them.
| JP3641165 | IRON OXIDE PARTICLE |
| JPS6032859 | [Title of the Invention] Electrostatic load development agent |
| JPH0222669 | MAGNETIC COLOR TONER |
INOUE SAJIROU
KATOU SHIGEO
UCHIIDE HITOSHI
