Magnetic toner
AssigneeCanon Kabushiki Kaisha
InventorsMichihisa Magome, Eriko Yanase, Tatsuya Nakamura
Life of this patent
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Abstract
A magnetic toner is disclosed including magnetic toner particles containing at least a binder resin and a magnetic powder. The magnetic powder contains a specific amount of phosphorus elements, and a specific amount of silicon elements, based on the iron element, with the ratio of the phosphorous element to the silicon elements being in a specific range, and has a specific volume-average particle diameter, a specific saturation magnetization in a specific magnetic field, and a specific residual magnetization. The magnetic toner can realize high image density and reduce fog and spots around line images regardless of environmental variation, and is superior in durability, and besides, can achieve small toner consumption.
Claims12
A magnetic toner comprising magnetic toner particles containing at least a binder resin and a magnetic powder, wherein
- said magnetic powder contains a phosphorus element in an amount of from 0.05% by weight to 0.25% by weight based on an iron element and a silicon element in an amount of from 0.30% by weight to 0.80% by weight based on the iron element, where a ratio of the phosphorous element to the silicon element (P/Si) is from 0.15 to 0.50, has a volume-average particle diameter (Dv) of from 0.15 μm to 0.35 am, has a saturation magnetization of from 67.0 A m2/kg (emu/g) to 75.0 A m2/kg (emu/g), and has a residual magnetization of 4.5 μm2/kg (emu/g) or less, in a magnetic field of 79.6 kA/m (1,000 oersted).
Dependencies are inferred from the claim text.