Fuji Xerox Co., Ltd.

Koichi Oyamada

Masanori Ichimura

Toru Murakami

Hiroshi Nakazawa

Toshiaki Murofushi

Shigeo Aonuma

Yasuhiro Ohya

Yoshimi Amagai

An electrophotographic is disclosed, comprising a binder resin, a coloring material, and a polyalkylene, wherein the polyalkylene has an average particle volume of 0.05 .mu.m.sup.3 or more. The toner exhibits broadened fixing latitude when fixed by heat roll fixing without using any offset inhibiting liquid.

Electrophotographic toner

A red color toner for electrophotography comprising a binder resin and a colorant component comprising C.I. Pigment Red 48:1, or C.I. Pigment Red 48:1 and a second red pigment which may be C.I. Pigment Red 122 or C.I. Pigment Red 57:1, or C.I. Pigment Red 48:1 and a yellow pigment which may be C.I. Pigment Yellow 97 or C.I. Pigment Yellow 12. The colorant preferably is present in an amount between about 1% and about 20% by weight of the binder resin.

Electrophotographic red toner

An electrophotographic developer is disclosed, that contains toner particles and fine particles of tin oxide having an electrical resistivity of from 10.sup.2 to 10.sup.9 .OMEGA..cm. The developer ensures efficient image transfer and exhibits good developing ability.

Electrophotographic developer containing tin oxide

An electrophotographic developer is described, comprising toner particles and carrier particles, characterized in that the toner particles have a layer of externally additive agents comprising fine metal oxide particles having an electric resistance of 1.times.10.sup.2 to 1.times.10.sup.9 .OMEGA..multidot.cm and fine silica particles and cleaning aid particles, and the layer of externally additive agents does not have a chain like structure.

Electrophotographic developer

An electrophotographic two-component system developer is described, comprising a positive charging toner and a negative charging carrier of the dispersed magnetic powder type, wherein a hydrophilic alumina particle is adhered onto the surface of said positive charging toner and a negative charging carrier has a volume average particle diameter of from 30 to 80 .mu.m. The developer provides reduced toner cloud upon development processing and provides toner images free from fog.

Two component electrophotographic developer

A positively chargeable electrophotographic developer is disclosed, comprising a carrier, toner particles positively chargeable by friction with the carrier, fine particles of hydrophilic alumina, and fine particles of one of tin oxide, hydrophobic silica and titanium dioxide. The developer hardly undergoes toner cloud or toner dropping during development and suffers neither extreme deterioration in charging properties nor fog formation even when used for taking a large number of copies.

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Kanagawa, Japan

Koichi Oyamada