Fuji Xerox Co., Ltd.

Rieko Kataoka

Satoshi Inoue

Chiaki Suzuki

Yosuke Tsurumi

Masahiro Takagi

Fusako Kiyono

Tetsuya Taguchi

Susumu Yoshino

Sakon Takahashi

Akihiro Iizuka

Koutarou Yoshihara

Atsuhiko Eguchi

Haruhide Ishida

Kaori Ohishi

Fumiaki Mera

Toshiyuki Yano

Norihito Fukushima

Michio Take

Masahiro Uchida

Hiroshi Takano

Yasuhiro Oya

Hiroyuki Fukuda

Masahiro Okita

Eiji Iwasaki

An electrostatic image developing carrier includes a ferrite particle that contains from about 1.0% by weight to about 14.0% by weight of elemental magnesium, wherein an average distribution ratio D of the elemental magnesium in the ferrite particle is from about 1.1 to about 2.0, wherein the average distribution ratio D is defined as an average value of D' of at least 50 ferrite particles, wherein D&#x2032; is defined as W1/W2, wherein W1 is a weight ratio of elemental magnesium content Mg to elemental iron content Fe, Me/Fe, in a whole cross-section of the ferrite particle, and W2 is a weight ratio of elemental magnesium content Mg to elemental iron content Fe, Me/Fe, in a square, the two opposite vertices of which are located at two points on a diameter of a circle circumscribing the cross-section, each being half a radius distant from the center of the circumscribing circle.

Electrostatic image developing carrier, process of making the same, electrostatic image developer, process cartridge, image forming method, and image forming apparatus

An electrostatic image developing toner includes a toner mother particle that contains a binder resin and a releasing agent; and an external additive that contains a zinc compound particle and a silica particle, wherein the zinc compound particle has a number average particle diameter of from about 2.0 &#x3bc;m to about 10.0 &#x3bc;m, the silica particle has a number average particle diameter of from about 60 nm to about 250 nm, the number of free zinc compound particles in all toner particles is from about 0.2% by number to about 1.0% by number, and the free zinc compound particle has an average circularity of about 0.6 or less.

Electrostatic image developing toner, electrostatic image developer, image forming method and image forming apparatus

An electrostatic image developing carrier includes a ferrite particle that contains magnesium element in an amount of about 3.0 wt % or more and about 10.0 wt % or less and manganese element in an amount of about 0.2 wt % or more and less than about. 1.0 wt %; and a resin layer that covers the ferrite particle.

Electrostatic image developing carrier, electrostatic image developer, process cartridge, image forming method, and image forming apparatus

An electrostatic image developing carrier includes a ferrite particle that contains magnesium element in an amount of about 3.0 wt % or more and about 10.0 wt % or less and manganese element in an amount of about 0.2 wt % or more and less than about 1.0 wt %; and a resin layer that covers the ferrite particle.

A toner for developing an electrostatic charge image, includes: a binder resin formed by reacting a polymerizable aromatic monomer having an ethylenically unsaturated double bond conjugated to an aromatic ring thereof, a nitrogen-containing polymerizable aliphatic monomer having an ethylenically unsaturated double bond and a sulfur-containing aliphatic compound to each other; and a colorant, wherein a ratio (MN/MS) of an amount of nitrogen (MN) to an amount of sulfur (MS) is in a range of from 1.0 to 15.

Toner for developing electrostatic charge image, electrostatic charge image developer, image forming method and image forming apparatus

An image formation method which remarkably extends developer life while providing size reduction and high speed coloring. Also, a replenishing toner and a method of producing the same, and a toner cartridge. In the image formation method, conducting image formation by an image formation apparatus having a plurality of xerography units, the developer apparatus of at least one xerography unit has a developer recovering mechanism appropriately replenishing a replenishing toner composed of a toner and a carrier into the developer apparatus and recovering an excess portion of a developer from the equipment. The above-mentioned replenishing toner has a carrier content in the range of 5 to 40% by weight, the above-mentioned carrier is a carrier coated with a resin having a specific composition, and/or the above-mentioned toner is in a specific shape. The replenishing toner may be produced using the above-mentioned recovered developer.

Image formation method, replenishing toner used in this method and method of producing the same, and carrier-containing toner cartridge

Electrophotographic toner, electrophotographic developer and process for forming image

Electrophotographic developer and process for forming image

A full color electrophotographic toner including toner particles containing at least a binder resin, a colorant and a wax, and external additives, at least one of the external additives being rutile titanium oxide having a volume resistivity of 1&times;10 to 1&times;10 &OHgr;cm, and a dispersion absolute deviation a of rutile titanium oxide being 0.17 or less, and a full color electrophotographic developer and an image forming method using the same are provided. In the full color electrophotographic toner, the full color electrophotographic developer and the image forming method of the invention, a retransfer phenomenon of the transferred toner can be prevented, a chargeability and a transferability are not problematic at all, a charging amount of the toner in long-term use can be rendered appropriate and stable, and a fluidity is also excellent.

Full color electrophotographic toner, full color electrophotographic developer and image forming method

Provided is a method for image formation capable of stably outputting high-quality images with no image density unevenness for a long period of time, in which the images formed are free from image defects of edge deletions and other deletions therein and which ensures good and uniform developability everywhere in the latent image region to be developed with preventing the latent image support used from being degraded. The method includes a step of forming a latent image on a latent image support, a step of developing the latent image on the latent image support with a two-component developer on a developer support disposed to face the latent image support, and a step of transferring the thus-developed toner image onto a transfer medium, wherein the developer support is a cylindrical sleeve having a diameter of at most 20 mm or the latent image support is a cylindrical sleeve having a diameter of at most 40 mm, and the resistance of the two-component developer is at least 10 &OHgr; in an electric field of 2 V/&mgr;m.

Method for forming color image

Growing community of inventors

Minami-ashigara, Japan

Rieko Kataoka