Fuji Xerox Co., Ltd.

Sueko Sakai

Chiaki Suzuki

Susumu Yoshino

Satoshi Inoue

Kaori Ohishi

Yoshifumi Iida

Motoko Sakai

Emi Takahashi

Seki Yamaguchi

Yasuo Matsumura

Hiroyuki Tanaka

Tetsuya Taguchi

Hirokazu Hamano

Masahiro Takagi

Manabu Serizawa

Seiichi Takagi

Toshiyuki Yano

Kazuhiko Yanagida

Shigeru Seitoku

Tsutomu Kubo

Hidekazu Yaguchi

Yasuhiro Oya

Hiroe Okuyama

Haruhide Ishida

Jun Igarashi

Yuusaku Shibuya

Koichi Kumashiro

Masayoshi Shinoki

Teruo Masukawa

The present invention relates to an image forming method including: a charging step; an electrostatic latent image forming step; a developing step; a transfer step; a fixing step; and a cleaning step, wherein an electrostatic latent image developing agent comprises a toner and a carrier, wherein particles which have a volume resistivity of at least 1&#xd7;10&#x3a9;cm and an average primary particle diameter of 50 nm or less has a higher covering ratio than other particles on the toner particle surfaces, a shape factor SFof the toner is in the range of from 100 to 140, the carrier is a resin coated carrier, and at least a coating resin layer comprises a positively charging resin and a quaternary ammonium salt compound.

Electrostatic latent image developing agent and image forming method

The present invention relates to an image forming method wherein the surface of an electrophotographic photoreceptor contains a compound having an unsaturated double bond, a toner for electrostatic latent image development has a binder resin obtained by polymerizing a polymerizable monomer having a vinyl double bond, has at least one kind of metal oxide particles and/or metal nitride particles on the surface of the toner and has a shape factor SFof 110 to 140, and the storage of elastic modulus at 160&#xb0; C. (G'(160)) of the toner for electrostatic latent image development is in a predetermined range.

Image forming method

An image forming method including a charging step, a latent image forming step, a developing step, a transfer step, and a cleaning step, wherein remaining toner recovered in the cleaning step is used as recycled toner, and a ratio of the recycled toner to a total amount of supply toner supplied to a developer is 15% by weight or greater.

Image forming method using recycled toner

The present invention provides toner for an electrostatic latent image developer, said toner being excellent in fluidity, chargeability, developability, transferability, and freedom from fogging on a photoreceptor and contamination of the interior of a developing device. The toner for an electrostatic latent image developer comprises spherical toner particles characterized by a shape index ML.sup.2 /A of less than 125 and has a correlation coefficient between X.sup.2/3 and Y, obtained by linear regression with respect to a straight line which passes through the origin of coordinate axes, of more than 0.6 where X is the light emitting voltage due to the carbon derived from the binder resin of the toner particles and Y is the light emitting voltage due to the element derived from the external additive.

Toner for developer of electrostatic latent image, method for producing

A carrier for developing an electrostatic latent image comprising a core material coated with a resin layer, wherein the F/N ratio of the surface of the resin layer ranges from 1 to 20. It is desirable that the resin layer include resin particles containing a nitrogen atom, that the average particle diameter of the nitrogen-atom-containing resin be in a range from 0.1 to 2 .mu.m, that the thickness of the resin layer be in a range from 0.1 to 10 .mu.m, that the resin layer include an electroconductive material which is in a condition to be dispersed in the resin layer, that the electroconductive material be made of carbon black, and that the average particle diameter of the carrier for developing an electrostatic latent image be in a range from 30 to 150 .mu.m. The carrier for developing an electrostatic latent image, which is long-lived, provided with a charging capability unchanged over time, and is capable of effectively preventing fogging are provided.

Carrier for developing electrostatic latent image, electrostatic latent

The present invention provides a long-life carrier for developing an electrostatic latent image to be used in such field of applications as electrostatic photography and electrostatic recording, a developer of an electrostatic latent image utilizing said carrier, a method for forming an image and an image forming apparatus by using said developer. By use of the foregoing qualities, a high-quality image can be obtained.

Developer of electrostatic latent image, carrier therefor, method for

A magnetic toner comprising a binder resin having dispersed therein a magnetic powder is disclosed, wherein the magnetic toner has a volume average particle diameter (D.sub.50) of from 4 to 9 .mu.m, the magnetic powder has a number average particle diameter of from 0.15 to 0.25 .mu.m (hereinafter simply referred to as a particle diameter), a BET specific surface area of from 6 to 8 m.sup.2 /g, and a residual magnetization of from 7 to 10 emu/g, the magnetic powder is present in an amount of from 30 to 70% based on the total weight of the magnetic toner, and the magnetic toner has adhered to the surface thereof silica powder having been rendered hydrophobic. The magnetic toner exhibits superior performance in terms of image density, definition, dot and fine line reproducibility, and environmental stability.

Magnetic toner

A toner for development of a latent electrostatic image containing a colorant and a binder resin formed of a mixture of a low-molecular weight component and a high-molecular weight component. Both the low-molecular weight component and high-molecular weight component are made from a styrene-acrylic copolymer where the weight ratio (A) of styrene to acrylic monomer in the low-molecular weight polymer component and an the weight ratio (B) of styrene to acrylic monomer in the high-molecular weight polymer component satisfies the relationship A/B.ltoreq.1.3. The mixing ratio of the low-molecular weight and high-molecular weight components is within the range of from 80:20 to 40:60. The weight-average molecular weight (Mw) and the number-average molecular weight (Mn) of the low-molecular weight polymer component satisfies the relationship Mw/Mn.ltoreq.3.0.

Functionally seprated type toner for fixing with heated rolls

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Minami-Ashigara, Japan

Sueko Sakai