Canon Kabushiki Kaisha

Hideyuki Takai

Hajime Miyazaki

Kazushi Iuchi

Itaru Yamazaki

Tetsuro Kanemaru

Masato Tanaka

Shintetsu Go

Koichi Suzuki

Shinichi Hakamada

Masakazu Matsumoto

Masako Udagawa

Hiroshi Kakikawa

Shuichi Okazaki

Mitsuhiro Kunieda

Satomi Sugiyama

Yuuhei Shimizu

Hideki Takayama

Kouhei Nakagawa

Takao Takiguchi

Toshiyuki Yoshihara

Hideki Anayama

Junichi Sakai

Kouichi Nakata

Masaaki Hiro

Kan Tanabe

Shinya Mayama

Makiko Endo

Hideyuki Ainoya

Harumi Sakoh

Keishi Danjo

Junichi Kishi

Toshie Miyaji

Nobuyuki Hanami

An ink contains at least a pigment, wherein the pigment is a solid solution of C.I. Pigment Red 202 and C.I. Pigment Violet 19, and a primary particle diameter D (nm) of the pigment and a 50%-cumulative diameter D(nm) in particle diameter distribution of the pigment satisfy a relation of D&#xd7;0.95&#x2266;(=&#x3c;)D&#x2266;(=&#x3c;)130, and a 90%-cumulative diameter D(nm) in particle diameter distribution of the pigment and the 50%-cumulative diameter D(nm) satisfy a relation of 1.5&#x2266;(=&#x3c;)D/D&#x2266;(=&#x3c;)2.2.

Ink, ink jet recording method, ink cartridge, and ink jet recording apparatus

An ink contains at least a pigment, wherein the pigment is C.I. Pigment Red 282, and a primary particle diameter D (nm) of the pigment and a 50%-cumulative diameter D50 (nm) in particle diameter distribution of the pigment satisfy a relation of D&#xd7;0.95&#x2266;D50&#x2266;150, and a 90%-cumulative diameter D90 (nm) in particle diameter distribution of the pigment and the 50%-cumulative diameter D50 (nm) satisfy a relation of 1.5&#x2266;D90/D50&#x2266;2.5.

The invention provides colored fine resin particles useful as coloring materials for inks which can provide images having good water fastness, weather fastness and rub-off resistance and are excellent in dispersion stability, and a production process thereof. The colored fine resin particles have a structure in which a pigment coated with a water-insoluble resin is encapsulated with a copolymer composed of at least a polymerizable unsaturated monomer and a reactive emulsifier.

Colored fine resin particles and production process thereof, aqueous dispersion of colored fine resin particles and production process of aqueous dispersion of colored fine resin particles, ink , ink cartridge, recording unit, ink-jet recording apparatus, and ink-jet recording process

An electrophotographic photosensitive member is disclosed which has a support and a photosensitive layer and is exposed to semiconductor laser light having a wavelength of from 380 nm to 500 nm. The photosensitive layer contains a gallium phthalocyanine compound, or an oxytitanium phthalocyanine compound having a strong peak at 27.2&deg; plus-minus 0.2&deg; of the diffraction angle in CuK&agr; characteristic X-ray diffraction. Also, disclosed are a process cartridge and an electrophotographic apparatus making use of the photosensitive member.

Electrophotographic photosensitive member process cartridge and electrophotographic apparatus

An electrophotographic photosensitive member is disclosed which is comprised of a support and a photosensitive layer provided thereon and is exposed to semiconductor laser light having a wavelength of from 380 nm to 500 nm. The photosensitive layer contains an azo pigment represented by the general formula: Ar&mdash;(&mdash;N&boxH;N&mdash;Cp),.

Electrophotographic photosensitive member, process cartridge, and electrophotographic apparatus

An electrophotographic photosensitive member is formed of a support, and a photosensitive layer disposed on the support. The photosensitive layer is characterized by containing an azo pigment having an organic group represented by formula (1) below: wherein A denotes a residue group of formula (1A) below: ##STR1## and k.sub.1, k.sub.2, Z.sub.1, Z.sub.2, D; R.sub.1 and R.sub.2 are defined in the text. The group of the formula (1) may provide at least one of up to 4 azo-substituents of the azo pigment having an entire structure represented by ##STR2## wherein Ar denotes an aromatic or heterocyclic core unit, Cp denotes a coupler residue group, and --(N.dbd.N--Cp) denotes such an azo-substituent. The photosensitive member can exhibit good electrophotographic performances including high and stable sensitivity on repetitive use.

Electrophotographic photosensitive member, process cartridge and

An electrophotographic photosensitive member, a process cartridge having the electrophotographic photosensitive member and an electrophotographic apparatus are provided. The electrophotographic photosensitive member has a conductive substrate and a photosensitive layer thereon, wherein the photosensitive layer contains a disazo pigment represented by the following formula (1): ##STR1## wherein R.sub.1 to R.sub.8 are the same or different and are each a hydrogen atom, a halogen atom, an alkyl group or an alkoxy group, n is a positive integer, A.sub.1 and A.sub.2 are the same or different and are each a coupler residual group having a phenolic hydroxyl group, and at least one of A.sub.1 and A.sub.2 is a coupler residual group represented by the following formula (2): ##STR2## wherein X.sub.1 is a residual group forming a polycyclic aromatic ring or a heterocyclic ring by condensing with a benzene ring, R.sub.9 and R.sub.10 are the same or different and are each a hydrogen atom, an alkyl group, an aryl group, an aralkyl group, a heterocyclic group or a residual group forming a cyclic amino group by bonding together, and Z.sub.1 is an oxygen atom or a sulfur atom.

A new crystalline form of oxytitanium phthalocyanine is characterized by main peaks specified by Bragg angles (2.theta..+-.0.2 degrees) of 7.4 degrees, 10.2 degrees, 12.5 degrees, 15.0 degrees. 16.3 degrees, 18.3 degrees, 22.4 degrees, 24.2 degrees, 25.2 degrees and 28.5 degrees in X-ray diffraction pattern based on CuK.alpha. characteristic X-rays. The oxytitanium phthalocyanine is formed by treating amorphous oxytitanium phthalocyanine with a solvent selected from the group consisting of monohydric alcohols having at least two carbon atoms, cellosolves, diethylene glycol monoethers and diacetone alcohol. The oxytitanium phthalocyanine is useful as a charge generating material for providing an electrophotographic photosensitive member, which shows a stably high sensitivity to long wavelength light.

Oxytitanium phthalocyanine, process for producing same and

An electrophotographic photosensitive member is constituted by disposing a photosensitive layer on a support. The photosensitive layer contains oxytitanium phthalocyanine and a specific disazo pigment of the formula (I) or (II) each characterized by having particular coupler residues. The photosensitive layer may preferably include a charge generation layer and a charge transport layer. The charge generation layer may preferably include a first charge generation layer containing the above disazo pigment of the formula (I) or (II) and a second charge generation layer containing the above oxytitanium phthalocyanine. The electrophotographic photosensitive member including the photosensitive layer described above is usable for providing an apparatus unit and an electrophotographic apparatus showing excellent electrophotographic characteristics such as high photosensitivity, good potential stability in repetitive use and good image-forming properties substantially providing no black spots.

Electrophotographic photosensitive member, electrophotographic apparatus

An to an electrophotographic photosensitive member includes a photosensitive layer containing a specified oxytitanium phthalocyanine and a polyvinyl acetal resin having a structural unit represented by Formula: ##STR1## wherein X is a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, a nitro group, or a cyano group; and Y is a fluorine atom, a chlorine atom, a bromine atom, a nitro group, or a cyano group. The photosensitive member maintains a low residual potential without deterioration of the sensitivity during repeated use.

Electrophotographic photosensitive member, and electrophotographic

An electrophotographic photosensitive member is constituted by an electroconductive support and a photosensitive layer disposed on the electroconductive support. The photosensitive layer contains a specific disazo pigment having a 2,2'-bis-1,3-benzdithiolene-diyl skeleton or a thiophene-diyl skeleton. The photosensitive member is effective for providing a process cartridge and an electrophotographic apparatus respectively including the photosensitive member with an excellent photosensitivity and a stable electric potential in repetitive use.

Electrophotographic photosensitive member, process cartridge including

The present invention relates to a process for producing a crystalline I-type oxytitanium phthalocyanine having strong peaks in CuK.alpha. characteristic X-ray diffraction at Bragg angles (2.theta..+-.0.2.degree.) of 9.0.degree., 14.2.degree., 23.9.degree., and 27.1.degree., comprising milling-treatment of oxytitanium phthalocyanine or an aqueous paste thereof with a solvent containing a saturated hydrocarbon solvent.

Process for producing crystalline I-type oxytitanium phthalocyanine

An electrophotographic photosensitive member has a conductive support, and a charge generating layer and a charge transporting layer. The charge generating layer contains an acetal resin obtained from a reaction of polyvinyl alcohol, alkyl aldehyde having a structure shown in Formula (1) below, and aryl aldehyde having a structure shown in Formula (2) below:

Electrophotographic photosensitive member and electrophotographic

A process for producing crystalline oxytitanium phthalocyanine showing strong peaks in CuK.alpha. characteristic X-ray diffraction at Bragg angles 2.theta..+-.0.2.degree. of 9.0.degree., 14.2.degree., 23.9.degree., and 27.1.degree., which comprises a dispersion treatment of the aqueous paste of oxytitanium phthalocyanine in an ether type compound.

Growing community of inventors

Yokohama, Japan

Hideyuki Takai