Canon Kabushiki Kaisha

Konica Corporation

Mitsubishi Kasei Corporation

Shinya Mayama

Kiyoshi Sakai

Noriko Ohtani

Katsumi Aoki

Naoto Fujimura

Takeshi Ikeda

Yoshinobu Baba

Teigo Sakakibara

Yuko Sato

Akio Maruyama

Toshiyuki Yoshihara

Hideki Anayama

Naoya Ogata

Noriyoshi Ogawa

Kunio Shimizu

Nobumasa Sasa

Shin Nagahara

Hideyuki Ainoya

Satoshi Kanayama

Manabu Watanabe

Masato Tanaka

Yuichi Hashimoto

Masahiro Inoue

Nobuhiko Takekoshi

Hitoshi Itabashi

Hideyuki Takai

Itaru Yamazaki

Yuzo Tokunaga

Toshiyuki Urano

Tetsuro Kanemaru

Hiroshi Aoto

Junichi Kishi

Tetsuya Masuda

Hiroshi Ide

Tadami Kinugawa

Nobuyuki Hanami

Yasuko Hayashi

Toshiaki Takada

Hideo Ohtaki

Yukoh Sato

A toner for developing electrostatic images is comprised of toner particles having a number average particle diameter of from 0.5 .mu.m to 5.0 .mu.m, in which toner particles with a particle diameter of 6.0 .mu.m or larger is included in a proportion of not more than 5% by number. The toner particles are obtained by a process having the steps of dispersing a monomer composition containing at least a colorant, a charge control agent, or a mixture of these, and a polymerizable monomer, in free space formed in a polymeric medium, and polymerizing the monomer composition dispersed in said free space.

Toner for developing electrostatic images containing fine powder

The present invention discloses a carrier for use in electrophotography and a two-component type developer for developing an electrostatic image comprising a toner and the carrier. The carrier has magnetic material and a resin. The resin has a polycarbonate resin having a crystallinity of 0.25 or less.

Carrier for electrophotography, and two-component type developer having

A carrier for use in electrophotography has carrier particles. The carrier particles each comprise a carrier core particle and a resin for coating the carrier core particle and having a resistivity of 10.sup.10 .OMEGA..multidot.cm or above under conditions of a temperature of 23.degree. C. and a humidity of 50% RH. The carrier particles have an average particle diameter of not larger than 100 .mu.m and a resistivity of 10.sup.10 .OMEGA..multidot.cm or above. The carrier particles comprise not less than 80% by number of resin-coated carrier particles whose carrier core particles are each coated with a resin in a coverage of not less than 90%.

Carrier for electrophotography, process for its production,

A two-component type developer for developing an electrostatic image is constituted by a toner and a carrier. The carrier is composed of a magnetic material and a resin either coating or dispersing the magnetic material. The resin comprises a copolymer having structural units of the following formulae [1] and [2]: ##STR1## wherein A denotes a C.sub.1 -C.sub.10 linear, branched or cyclic alkylidene group, aryl-substituted alkylidene group or arylenedialkylidene group, --O--, --S--, --CO--, --SO-- or --SO.sub.2 --; and R.sub.1 -R.sub.4 independently denote hydrogen, halogen, or a C.sub.1 -C.sub.4 alkyl or alkenyl group: ##STR2## wherein R.sub.5 denotes a C.sub.2 -C.sub.6 alkylene or alkylidene group; R.sub.6 and R.sub.7 denote a C.sub.1 -C.sub.3 alkyl group, a phenyl group or a substituted phenyl group; and n is an integer of 1-200.

Carrier for use in electrophotography and two component-type developer

A transfer material carrying member has a copolymer and conductive particles; the copolymer has a component unit represented by the Formula (I) and a component unit represented by the Formula (II), and the component unit represented by Formula (II) is in an amount of from 0.1% by weight to 50% by weight based on the total weight of the copolymer.

Transfer material carrying member and image forming apparatus making use

Process for producing toner particles using free space formed in a

The present invention relates to an electrophotographic photosensitive member comprising an electroconductive support and a photosensitive layer formed thereon: the surface layer of the electrophotographic photosensitive member containing a first copolymer of a first construction unit represented by Formula (1) and a second construction unit represented by Formula (2), and a second copolymer of a third construction unit represented by Formula (3) and a fourth construction unit represented by Formula (4): ##STR1##

Electrophotographic photosensitive member, and electrophotographic

There is disclosed an electrophotographic photosensitive member comprising a conductive support and a photosensitive layer provided thereon, wherein the photosensitive layer contains a random copolymer having a structural unit represented by the following Formula (I): ##STR1## and a structural unit represented by the following Formula (II): ##STR2##

An electrophotographic photosensitive member is formed by disposing a photosensitive layer and a protective layer in this order on an electroconductive support. The protective layer is formed from a resin obtained by polymerization of a curable acrylic monomer having at least three acrylic groups, i.e., acryloyl and/or methacryloyl groups. The protective layer not only shows a good durability against wearing but also can contain fine electroconductive particles therein with a good dispersibility because of the presence of the acrylic groups aiding the dispersion.

Electrophotographic photosensitive member

An image holding member rich in durability and suitably used as an electrophotographic photosensitive member or an electrostatic image-holding dielectric member is prepared by coating a support with a resinous layer formed by polymerization of a phosphazene polyene represented by the following formida: ##STR1## wherein R.sub.1 denotes an ethylenically unsaturated group, preferably an acrylic group represented by --R.sub.2 --OCO--C(R.sub.3)=CH.sub.2, wherein R.sub.2 denotes an alkylene group, arylene group, alkyl-substituted arylene group, alkylamide group or arylamide group, and R.sub.3 denotes a hydrogen atom or a methyl group. The resinous layer may constitute a photosensitive layer, a dielectric layer, or a protective layer covering these layers.

Image holding member

Disclosed is a multi-color transfer image forming method, which comprises subjecting a colored image forming material having a coloration recording layer comprising at least two layers and containing a photosensitive material and a colorant on a support to aqueous development after imagewise exposure, thereby forming a colored image, transferring the colored image to an image receiving member through the outermost surface of the coloration recording layer and then transferring at least one colored image with different hue onto the same image receiving member in conformity with the colored image, characterized in that the layer of the coloration recording layer remotest from the support is a layer adherable to the image receiving member, and only the colored image portion is transferred onto the image receiving member to have the image receiving member surface exposed at the non-image portion of the multi-color image. According to the present invention, the treating process of multi-color transfer image becomes simpler and also a transferred image approximate to a printed matter can be obtained.

Multi-color transfer image forming method to form color proofs

An electrophotographic photosensitive medium has a photosensitive layer on an electroconductive base, the medium having at least one intermediate layer between the base and the photosensitive layer, the intermediate layer containing indium oxide - tin oxide solid solution (ITO) powder and a binder resin. An electrophotographic apparatus includes a photosensitive medium; a device for forming latent images; a device for developing formed latent images; and a device for transferring developed images to a transfer member.

Electrophotographic photosensitive member and apparatus using same

The present invention provides an image-holding member which comprises an electroconductive support and a resin layer formed on the support, wherein the surface layer of the image-holding member contains a copolymer having the structure units represented by the formulas [I] and [II]: ##STR1## where A is a linear, branched or cyclic alkylidene group of 1 to 10 carbon atoms, an aryl-substituted alkylidene group, arylene-dialkylidene group, --O--, --S--, --CO--, --SO--, or --SO.sub.2 --; and R.sub.1, R.sub.2, R.sub.3, and R.sub.4 are respectively hydrogen, halogen, or an alkyl or alkenyl group of 1 to 4 carbons; ##STR2## where R.sub.5 is an alkylene or alkylidene group of 2 to 6 carbons; R.sub.6 and R.sub.7 are respectively an alkyl group of 1 to 3 carbons, a phenyl or substituted phenyl group; and n is an integer of from 1 to 200, and the copolymer containing the structure unit of the formula [II] in an amount of from 0.1 to 50% by weight Of the total weight of the copolymer.

Image-holding member, and electrophotographic apparatus, apparatus unit,

The present invention provides an electrophotographic photosensitive member comprising a conductive support and a photosensitive layer provided thereon, wherein the surface layer of the electrophotographic photosensitive member contains a polymer having a component unit represented by the following Formula (1) and a polymer having a component unit represented by the following Formula (2) and a component unit represented by the following Formula (3) in a certain proportion. ##STR1##

The present invention relates to an electrophotographic photosensitive member. The photosensitive member has an electroconductive support and a photosensitive layer formed thereon containing oxytitanium phthalocyanine, and a surface layer of the photosensitive member contains a copolymer having a first and second structural units represented by the formulas ##STR1## Further the invention relates to an electrophotographic apparatus, device unit, and facsimile machine utilizing the electrophotographic photosensitive member.

Growing community of inventors

Yamato, Japan

Shinya Mayama