Ricoh Company, Ltd.

Hodogaya Chemical Co., Ltd.

Richoh Company, Ltd.

Masafumi Ohta

Masaomi Sasaki

Mitsuru Hashimoto

Kiyoshi Sakai

Tomoyuki Shimada

Kyoji Tsutsui

Akio Kozima

Mitsutoshi Anzai

Yohta Sakon

Toshihiko Takahashi

Kazukiyo Nagai

Tamotsu Aruga

Akihiro Imai

Yoshiki Yanagawa

Tetsuro Suzuki

Yuuji Tanaka

Chihaya Adachi

Fumio Kawamura

Masayuki Shoshi

Akio Kojima

Teruyuki Ohnuma

Hiroshi Tamura

Eiji Kurimoto

Keisuke Shimoyama

Atsushi Takesue

Katsuhiro Morooka

Hiromi Sakaguchi

Masao Yoshikawa

Hiromi Tada

Yasuo Murakami

Tatsuya Niimi

Hiroshi Ikuno

Hongguo Li

Toshio Fukagai

Michio Kimura

Megumi Kawahara

Masakatsu Shimoda

Tomiko Kawakami

Kaoru Teramura

Norio Nagayama

Zenjiro Okuno

Takeo Kazami

Ryohei Miyake

To provide a gallium phthalocyanine compound, which is expressed by the following general formula (I): where R1 to R32 are each independently a hydrogen atom, an alkoxy group, an alkylthio group, an alkyl group, a halogen atom, a nitro group, or an aryl group.

Gallium phthalocyanine compound, gallium phthalocyanine composite pigment, method for preparing gallium phthalocyanine composite pigment, and electrophotographic photoconductor

An azo compound having the following formula (I):A(E)&#x2003;&#x2003;(I)wherein A represents a residue of an azo compound, bonded with n pieces of E group through one or more heteroatom being N or O and forming a part of the residue A; E independently represents a hydrogen atom or &#x2014;C(&#x2550;O)&#x2014;O&#x2014;R1 wherein R1 represents a substituted or an unsubstituted alkyl group having 4 to 10 carbon atoms, an alkenyl group, an alkynyl group, a cycloalkyl group, a cycloalkenyl group or an aralkyl group; and n represents an integer of from 1 to 10.

Azo compound and method of preparing the azo compound

A hydroxygallium phthalocyanine composite pigment, which is a composite pigment wherein an azo compound expressed by the following general formula (a) is conjugated to a hydroxygallium phthalocyanine pigment, wherein the hydroxygallium phthalocyanine composite pigment has diffraction peaks at least at 7.5&#xb0;, 9.9&#xb0;, 12.5&#xb0;, 16.3&#xb0;, 18.6&#xb0;, 25.1&#xb0;, and 28.3&#xb0; on an X-ray diffraction spectrum with Bragg angle of 2&#x3b8;&#xb1;0.2&#xb0;, using Cu&#x2014;K&#x3b1; X-rays:A(H)&#x2003;&#x2003;General Formula (a)where A is a residue of an azo compound; H is a hydrogen atom; the residue A is bonded to one or more hydrogen atoms, where the number of the hydrogen atoms is expressed with n, via one or more heteroatoms which are selected from the group consisting of N and O, and form part of the residue A; and n is an integer of 1 to 9.

Hydroxygallium phthalocyanine composite pigment, electrophotographic photoconductor containing the same, and image forming device and process cartridge for image forming device using the same

A gallium phthalocyanine compound represented by the following chemical structure I, 

Gallium phthalocyanine compound, and image bearing member, image forming method, image forming apparatus, and process cartridge using the gallium phthalocyanine compound

An image forming apparatus including at least an image bearing member having a substrate having a photosensitive layer thereon, the image bearing member to bear a latent electrostatic image on a surface thereof, a charging device to the surface of the image bearing member, an irradiation device to irradiate the surface of the image bearing member with light to form a latent electrostatic image thereon, a development device to develop the latent electrostatic with toner to obtain a developed image, a transfer device to transfer the developed image to a recording medium, and a cleaning device to clean the surface of the image bearing member, wherein the photosensitive layer includes naphthalene tetracarbonic acid diimide derivative as a charge transport material represented by the following Chemical Structure (1):  In the Chemical Structure (1), Z represents a group represented by the following Chemical Formula (1): or the following Chemical Formula (2):&#x2014;R&#x2003;&#x2003;Chemical Formula (2). In the Chemical Structure (1), and the Chemical Formulae (1) and (2), R, R, R, Rand Reach, independently, represent a substituted or non-substituted alkyl group or a substituted or non-substituted aromatic hydrocarbon group, R, R, Rand Reach, independently, represent hydrogen atom, a substituted or non-substituted alkyl group, or a substituted or non-substituted aromatic hydrocarbon group, and Rand Rand Rand Roptionally share a bond connectivity to form a substituted or non-substituted heterocyclic group including a nitrogen atom.

Image forming apparatus and process cartridge

An azo compound having the following formula (I):A(E)n&#x2003;&#x2003;(I)wherein A represents a residue of an azo compound, bonded with n pieces of E group through one or more heteroatom being N or O and forming a part of the residue A; E independently represents a hydrogen atom or &#x2014;C(&#x2550;O)&#x2014;O&#x2014;R1 wherein R1 represents a substituted or an unsubstituted alkyl group having 4 to 10 carbon atoms, an alkenyl group, an alkynyl group, a cycloalkyl group, a cycloalkenyl group or an aralkyl group; and n represents an integer of from 1 to 10.

The present invention provides a naphthalenetetracarboxylic acid diimide derivative represented by the following general formula (1): wherein Rand R, which are identical or different, each represent a substituted or non-substituted alkyl group or a substituted or non-substituted aromatic hydrocarbon group; Rrepresents an alkyl group having 1 to 8 carbon atoms or an aromatic hydrocarbon group; R, R, Rand R, which are identical or different, each represent a hydrogen atom, a substituted or non-substituted alkyl group, or a substituted or non-substituted aromatic hydrocarbon group; and Rand Rmay be linked to form a substituted or non-substituted heterocyclic group including a nitrogen atom; with compounds where all of R, Rand Rare a methyl group, and compounds where both of Rand Rare a methyl group and Ris a 1-octyl group being excluded.

Naphthalenetetracarboxylic acid diimide derivative and electrophotographic photoconductor having the same

An electrophotographic photoreceptor, including an electroconductive substrate; and a photosensitive layer overlying the substrate, wherein the photosensitive layer comprises a complex azo pigment comprising an azo compound having the following formula (a):A(H)&#x2003;&#x2003;(a)wherein A represents a residue of an azo compound, bonded with n pieces of hydrogen atom through one or more heteroatom being N or O and forming a part of the residue A; H represents a hydrogen atom; and n represents an integer of from 1 to 9,and a pigment.

Electrophotographic photoreceptor, and image forming apparatus and process cartridge therefor using the photoreceptor

A method of preparing a complex-azo pigment having plural pigment components including at least an azo pigment represented by the following formula (a)A(H)&#x2003;&#x2003;(a)Pigments, both limited and unlimited by the process of making.

Method of preparing complex-AZO pigment and complex-AZO pigment thereof

An electrophotographic photoreceptor is provided, including an electroconductive substrate and a photosensitive layer located overlying the electroconductive substrate, wherein an outermost layer of the electrophotographic photoreceptor includes a resin including a graft copolymer in which a monomer having a polar group is graft polymerized to a polycarbonate resin, a polyarylate resin, or a copolymer thereof, and a filler; along with an image forming apparatus and a process cartridge using the electrophotographic photoreceptor.

Electrophotographic photoreceptor, and image forming apparatus and process cartridge using the electrophotographic photoreceptor

An electrophotographic photoconductor includes an electroconductive support, and a photoconductive layer formed thereon containing as an effective component an aromatic polycarbonate resin having a structural unit of formula (I), two structural units of formulae (I) and (II), or a repeat unit of formula (III):

Electrophotographic photoconductor and aromatic polycarbonate resin for use therein

An optically anisotropic recording medium and a method of recording and erasing method using the recording medium are disclosed, which comprises the steps of applying heat or light to the recording medium which comprises a recording layer made of optically anisotropic organic thin-film-shaped crystals to raise the temperature of an organic material or which comprises the optically anisotropic organic thin-film-shaped crystals to a recording temperature at which the crystals are fused, performing partial changing of the crystalline state of the crystals by rapidly cooling the recording layer, thereby recording information in the recording layer; and heating the recording layer to an erasing temperature which is lower than the recording temperature, at which the crystals are not fused, but the molecules thereof can be thermally moved.

Optically anisotropic recording medium and method of recording and

An electrophotographic photoconductor includes an electroconductive support, and a photoconductive layer formed thereon containing as an effective component an aromatic polycarbonate resin having a structural unit of formula (I), two structural units of formulae (I) and (II), or a repeat unit of formula (III): ##STR1## wherein Ar.sup.1 to Ar.sup.7, Y, X, and n are as specified in the specification.

Electrophotographic photoconductor and aromatic polycarbonate resin for

An electrophotographic photoconductor includes an electroconductive support, and a photoconductive layer formed thereon, containing a novel aromatic polycarbonate resin having a repeat unit of formula (I): ##STR1## wherein R.sup.1, R.sup.2 and R.sup.3 each is an alkyl group which may have a substituent, or a halogen atom; R.sup.4 is a hydrogen atom, or an alkyl group which may have a substituent; Ar.sup.1 and Ar.sup.2 each is an aromatic hydrocarbon group which may have a substituent; l, m and n each is an integer of 0 to 4; k is an integer of 5 to 5,000; and X is a bivalent aliphatic group, a bivalent cyclic aliphatic group, or ##STR2## in which R.sup.5 and R.sup.6 each is an alkyl group which may have a substituent, a halogen atom, or an aromatic hydrocarbon group; p and q each is an integer of 0 to 4; and r is 0 or 1, and when r is 1, Y is a straight-chain, branched or cyclic alkylene group having 1 to 12 carbon atoms, --O--, --S--, --SO--, --SO.sub.2 --, or --C(O)--.

Electrophotographic photoconductor, aromatic polycarbonate resin for use

Growing community of inventors

Susono, Japan

Masafumi Ohta