Fuji Xerox Co., Ltd.

Haruhide Ishida

Yasuhiro Oya

Hirokazu Hamano

Susumu Yoshino

Masanobu Ninomiya

Tetsuya Taguchi

Koutarou Yoshihara

Sakon Takahashi

Fumiaki Mera

Akihiro Iizuka

Shinpei Takagi

Hidekazu Yaguchi

Atsuhiko Eguchi

Hiroshi Takano

Kaori Ohishi

Rieko Kataoka

Jun Igarashi

Yuusaku Shibuya

Satoshi Inoue

Chiaki Suzuki

Yoshifumi Iida

Takayoshi Aoki

Manabu Serizawa

Ikutaroh Nagatsuka

Noriyuki Mizutani

Toshiyuki Yano

Yutaka Sugizaki

Michio Take

Masahiro Uchida

Sueko Sakai

Etsuo Tominaga

Tomohiro Takeda

Kaori Oishi

Yusaku Shibuya

Toyohumi Inoue

Kouzou Ota

A toner for developing an electrostatic latent image, wherein in regard to the molecular weight by GPC of the THF dissolved components of the toner, the ratio of at least 5&times;10 in the integral molecular weight distribution is not higher than 1% by weight, the ratio of not higher than 3&times;10 is not higher than 30% by weight, and the ratio &lcub;W(5&times;10 )/W(1&times;10 )&rcub; of the ratio &lcub;W(5&times;10 )&rcub; of not higher than 5&times;10 to the ratio &lcub;W(1&times;10 )&rcub; of at least 1&times;10 is from 15 to 50. Also, the molecular weight by GPC of the THF dissolved components of the toner is distributed in the range of not larger than 1&times;10 , the value of the differential molecular weight distribution of the molecular weight of 5&times;10 is not larger than 0.55%, and the value of the differential molecular weight distribution of the molecular weight of 1&times;10 is not larger than 0.15%.

Toner for developing electrostatic latent image, two-component developer, and image-forming process

A toner for developing an electrostatic latent image contains a binder resin, a colorant, a wax, and inorganic fine particles. The toner contains the inorganic fine particles content in the range from 1 to 10% by weight, the temperature at which the complex viscosity &eegr;&deg; of the toner in the case of measuring at a frequency of 100 rad/second shows 1000 Pa.s ranges from 125 to 145&deg; C., and the temperature at which the complex viscosity &eegr;&deg; of the toner in the case of measuring at a frequency of 100 rad/second shows 100 Pa.s ranges from 180 to 210&deg; C.

Toner for developing electrostatic latent image, two-component developer and image-forming process

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

Full-color toner cartridge, method for supplying toner from cartridge and method for filling toner cartridge with toner

Provided is an image-forming process including a step of forming an electrostatic latent image on a latent image-carrier and a step of developing the latent image by a developer on a developer-carrier disposed facing the electrostatic latent image-carrier, a developer contains a color toner containing a wax which amount is from 1 to 10% by weight of the toner is used, and the developer-carrier wherein a ten-point average roughness (Rz) of the surface thereof of and the average spacing (Sm) of roughness peaks meet the following formula is used; 5.ltoreq.Rz.times.20.ltoreq.Sm. By the process, the conveying property of the developer is good, staining of the surface of the developer-carrier can be prevented, and images having a high quality and excellent in the fixing property over a long period time is obtained even in the case of using oil-less color toners containing a wax.

Image-forming process

An electrostatic latent image developer including a toner, which is formed from an outer additive and non-magnetic resin particles containing a binder resin and a coloring agent, and a carrier, in which a resin coating layer in which electroconductive fine powder is dispersed in a matrix resin is formed on a core, wherein a volume specific resistivity of said carrier is greater than or equal to 10.sup.9 .OMEGA..multidot.cm at an electric field strength of 3000 V/cm and is less than or equal to 10.sup.13 .OMEGA..multidot.cm at an electric field strength of 10000 V/cm, said outer additive contains titanium oxide whose volume specific resistivity of a compression-molded molded product is greater than or equal to 10.sup.6 .OMEGA..multidot.cm at an electric field strength of 3000 V/cm and is less than or equal to 10.sup.10 .OMEGA..multidot.cm at an electric field strength of 10000 V/cm, and a volume specific resistivity of said electrostatic latent image developer when a toner concentration is greater than or equal to 2% is greater than or equal to 10.sup.11 .OMEGA..multidot.cm at an electric field strength of 3000 V/cm. Further, the present invention provides an image forming method including steps of forming a latent image on a latent image holding member, and developing the latent image by using said electrostatic latent image developer.

Electrostatic latent image developer and image forming method

The toner for developing an electrostatic charge image comprises a colorant, a binding resin and a resin copolymer of aliphatic hydrocarbon and aromatic hydrocarbon having 9 or more of carbon atoms. Preferably, the toner further comprises a wax. The endothermic peak of the wax at DSC is preferably from 70 to 100.degree. C. The petroleum resin copolymer preferably has a ring and ball softening point of from 80 to 170.degree. C., and the binding resin is preferably a polyester resin. The weight ratio of the aromatic hydrocarbon monomer and the aliphatic hydrocarbon monomer of the petroleum resin copolymer is preferably from 99:1 to 50:50.

Toner for developing an electrostatic charge image, developing agent for

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 image formation process comprising the steps of forming an electrostatic latent image on an electrostatic latent image carrier, developing the electrostatic latent image with a developer to provide a toner image, transferring the toner image to a transfer material, and heat-fixing the toner image on the transfer material, wherein the developer comprises a toner for developing electrostatic latent images comprising a binder, a colorant, and 1 to 30% by weight of a lubricant which comprises a modified polyethylene wax which is obtained by homopolymerizing ethylene or copolymerizing ethylene and an .alpha.-olefin having 3 to 10 carbon atoms in the presence of a metallocene catalyst and modifying the resulting ethylene homo- or copolymer by grafting at least one grafting monomer selected from the group consisting of a styrene monomer and an unsaturated carboxylic acid monomer, and has a hexane extraction of not more than 65% by weight, and wherein the transfer step comprises bringing a bias roll into contact with the back side of a transfer material. The image formation process of the present invention requires less power consumption. The toner for use in the present invention provides a good releasability at low temperatures and shows excellent anti-offset properties and powder fluidity without causing the generation of ozone, image defects and blocking.

Image formation process

The present invention provides an electrostatic image developing carrier which exhibits an enhanced maintenance of image quality, can be prevented from being attached to the image and thus can provide an image free of uneven density and background stain and an electrostatic image developer comprising said carrier. A novel electrostatic image developing carrier comprising a ferrite is provided, characterized in that said ferrite has a copper content of from 0.1 ppm to 2,500 ppm, a zinc content of from 0.1 ppm to 5,000 ppm and a nickel content of from 0.1 ppm to 2,000 ppm.

Electrostatic image developing carrier and electrostatic image developer

Growing community of inventors

Minami-ashigara, Japan

Haruhide Ishida