Electrically Insulating Overlayer Patents (Class 430/67)
  • Patent number: 7043175
    Abstract: In an image forming system, an image-bearing member having a photoconductor layer comprising an Si-based non-single crystal material is charged at a relatively low potential of 250 to 600 volts by a contact charging member in the presence of electroconductive fine powder. An electrostatic latent image formed on the image-bearing member is developed with a magnetic toner which includes magnetic toner particles comprising at least a binder resin and a magnetic iron oxide, and inorganic fine powder and electroconductive fine powder present at the surface of the magnetic toner particles. The magnetic toner has a weight-average particle size of 3-10 ?m and an average circularity of 0.950 to 0.995, and contains 0.05 to 3.00% of isolated iron-containing particles.
    Type: Grant
    Filed: November 15, 2001
    Date of Patent: May 9, 2006
    Assignee: Canon Kabushiki Kaisha
    Inventors: Keiji Komoto, Tsuyoshi Takiguchi, Tatsuhiko Chiba, Michihisa Magome, Akira Hashimoto, Takeshi Kaburagi
  • Patent number: 6939651
    Abstract: An electrophotographic photoconductor comprising at least an electroconductive support and a photoconductive layer which is formed on said electroconductive support, the outermost layer of the photoconductor contains particles comprising a polyorganosiloxane-containing phase which contains polyorganosiloxane and an organic polymer-containing phase which contains organic polymer without silicon and has a polyorganosiloxane content which is less than the polyorganosiloxane-containing phase, each phase being exposed at the top surface of the photoconductor.
    Type: Grant
    Filed: June 21, 2002
    Date of Patent: September 6, 2005
    Assignee: Ricoh Company, Ltd.
    Inventors: Hongguo Li, Kazukiyo Nagai, Masaomi Sasaki, Shinichi Kawamura, Yasuo Suzuki, Nozomu Tamoto, Kawori Tanaka
  • Patent number: 6936388
    Abstract: An electrophotographic photoreceptor in which at least a photosensitive layer is provided above an electroconductive substrate, the outermost surface layer of the electroconductive substrate contains at least an inorganic filler, a binder resin, and an aliphatic polyester, or, alternatively, the outermost surface layer of the electroconductive substrate contains at least an inorganic filler and a binder resin and the binder resin is a copolymer polyarylate having an alkylene-arylcarboxylate structural unit, also an image forming method, image forming apparatus, and image forming apparatus processing unit in which the electrophotographic photoreceptor is used.
    Type: Grant
    Filed: March 25, 2002
    Date of Patent: August 30, 2005
    Assignee: Ricoh Company, Ltd.
    Inventors: Tetsuro Suzuki, Kazukiyo Nagai, Nozomu Tamoto, Eiji Kurimoto, Hidetoshi Kami
  • Patent number: 6936387
    Abstract: An electrophotographic photoreceptor that can sufficiently prevent occurrence of filming, whereby defects on an image can be sufficiently prevented, and an electrophotographic process cartridge and an electrophotographic apparatus using the electrophotographic photoreceptor are to be provided. The electrophotographic photoreceptor contains an electroconductive substrate having provided thereon a photosensitive layer, and an outermost layer of the photosensitive layer has a dynamic hardness of about from 13.0×109 to 100.0×109 N/m2. According to the invention, occurrence of flaws on the surface of the photoreceptor can be sufficiently prevented, and cracking of a member made in contact with the photoreceptor can also be sufficiently prevented. Therefore, occurrence of filming is sufficiently prevented, and occurrence of defects on an image is also sufficiently prevented.
    Type: Grant
    Filed: December 13, 2001
    Date of Patent: August 30, 2005
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Kenji Yao, Wataru Yamada, Kazuhiro Koseki, Katsumi Nukada
  • Patent number: 6933090
    Abstract: The present invention relates to a photosensitive member for electrophotography which comprises a electroconductive support and one or more layers that include a photosensitive layer formed on the surface of the electroconductive support, wherein the outermost layer comprises binder resin, fluororesin particles A and fluororesin particles B.
    Type: Grant
    Filed: December 11, 2003
    Date of Patent: August 23, 2005
    Assignee: Konica Minolta Business Technologies, Inc.
    Inventors: Keiichi Inagaki, Shigeaki Tokutake, Takeshi Ishida
  • Patent number: 6911288
    Abstract: An imaging member having a substrate, a charge transport layer having charge transport materials dispersed therein, and an overcoat layer, wherein at least one of the charge transport layer and the overcoat layer comprise nano-size fillers having a particle size of from about 1 to about 250 nanometers.
    Type: Grant
    Filed: May 15, 2003
    Date of Patent: June 28, 2005
    Assignee: Xerox Corporation
    Inventors: H. Bruce Goodbrand, Nan-Xing Hu, Ah-Mee Hor, Cheng-Kuo Hsiao, Yvan Gagnon, Cuong Vong
  • Patent number: 6869741
    Abstract: A photoreceptor with good mechanical and physical properties is provided with an overcoat layer comprising a copolymer of an ?,?-ethylenically unsaturated carboxylic acid and an ?,?-ethylenically unsaturated monomer wherein the weight percent of the ?,?-ethylenically unsaturated carboxylic-acid is at least 25% up to 99% of the copolymer. The copolymer may comprise an ?,?-ethylenically unsaturated carboxylic acid and an ?,?-ethylenically unsaturated monomer wherein the copolymer has an acid value of at least 150 mg KOH/g the copolymer. The copolymer may be present in a blend with a second polymer or copolymer comprised of units derived from a second ?,?-ethylenically unsaturated monomer that is different from the an ?,?-ethylenically unsaturated carboxylic acid and/or the ?,?-ethylenically unsaturated monomer.
    Type: Grant
    Filed: June 10, 2002
    Date of Patent: March 22, 2005
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Jiayi Zhu, Zbigniew Tokarski, Ronald J. Moudry, Kristine A. Fordahl, David T. Ask, Jonas Sidaravicius, Edmundas Montrimas, Kam W. Law, Valentas Gaidelis
  • Patent number: 6858362
    Abstract: An electrophotographic photoreceptor including an electroconductive substrate, a photosensitive layer located overlying the electroconductive substrate, and optionally a protective layer overlying the photosensitive layer, wherein an outermost layer of the photoreceptor includes a filler, a binder resin and an organic compound having an acid value of from 10 to 700 mgKOH/g. The photosensitive layer can be the outermost layer. A coating liquid for an outermost layer of a photoreceptor including a filler, a binder resin, an organic compound having an acid value of from 10 to 700 mgKOH/g and plural organic solvents. A method for preparing a photoreceptor including forming a photosensitive layer, and coating the coating liquid on the photosensitive layer. An image forming method and apparatus and a process cartridge using the photoreceptor are also provided.
    Type: Grant
    Filed: July 23, 2003
    Date of Patent: February 22, 2005
    Assignee: Ricoh Company, Ltd.
    Inventors: Nozomu Tamoto, Tetsuro Suzuki, Hiroshi Tamura, Tatsuya Niimi, Akihiko Matsuyama, Eiji Kurimoto, Hidetoshi Kami
  • Patent number: 6846600
    Abstract: A process for producing an electrophotographic photosensitive member comprising the steps of depositing a non-single crystal material composed basically of silicon atoms, on a cylindrical substrate in a deposition chamber, thereafter once taking the substrate with film out of the deposition chamber, then returning it to the deposition chamber, and thereafter again depositing thereon a non-single-crystal material composed basically of carbon atoms. In another embodiment, the process comprises the steps of depositing on a cylindrical substrate a photoconductive layer formed of a non-single crystal material, subjecting to surface processing the deposited film having protrusions present at its surface, and depositing on the processed surface a surface protective layer formed of a non-single-crystal material. Also disclosed is the electrophotographic photosensitive member thus obtained, and an electrophotographic apparatus having that member.
    Type: Grant
    Filed: January 31, 2002
    Date of Patent: January 25, 2005
    Assignee: Canon Kabushiki Kaisha
    Inventors: Toshiyuki Ehara, Junichiro Hashizume, Masaya Kawada, Tetsuya Karaki, Hironori Ohwaki, Kunimasa Kawamura, Ryuji Okamura, Kazuto Hosoi
  • Publication number: 20040259010
    Abstract: A solid-state imaging device including a substrate corresponding to a pixel. The substrate carries thereon a light receiving section, which is a stack of, in this order, a photoconductive layer for absorbing light in a wavelength region for red, a photoconductive layer for absorbing light in a wavelength region for green, and a photoconductive layer for absorbing light in a wavelength region for blue. A transparent electrode layer is provided on each of the photoconductive layers. The transparent electrode layer placed above the photoconductive layer and the transparent electrode layer placed below the photoconductive layer are sandwiching a translucent reflective layer for reflecting the light in the green wavelength region. Similarly, a translucent reflective layer is sandwiched between the transparent electrode layer placed above the photoconductive layer and the transparent electrode layer placed below the photoconductive layer for reflecting the light in the blue wavelength region.
    Type: Application
    Filed: May 4, 2004
    Publication date: December 23, 2004
    Inventor: Hideo Kanbe
  • Publication number: 20040234875
    Abstract: An electrophotographic photoconductor includes an electroconductive substrate, a charge generation layer, and a charge transport layer formed by using a halogen-free solvent, arranged in this order, in which the charge generation layer contains a charge generation material having an average particle diameter smaller than a surface roughness of a plane where the electroconductive substrate is arranged, and a polyvinyl acetal resin having a ratio Mw/Mn of a weight-average molecular weight Mw to a number-average molecular weight Mn is 2.2 or more.
    Type: Application
    Filed: March 19, 2004
    Publication date: November 25, 2004
    Inventors: Naohiro Toda, Tatsuya Niimi, Ryohichi Kitajima, Yoshiaki Kawasaki
  • Patent number: 6815135
    Abstract: In an electrophotographic photosensitive member comprising a conductive support, and provided thereon a charge generation layer, a charge transport layer and a protective layer in this order, the layer thickness a0 (&mgr;m) of the charge transport layer at the middle portion of the conductive support in its generatrix direction, the layer thickness b0 (&mgr;m) of the protective layer at the middle portion of the conductive support in its generatrix direction, the layer thickness a (&mgr;m) of the charge transport layer at a portion other than the middle portion and the layer thickness b (&mgr;m) of the protective layer at the portion other than the middle portion satisfy the following expression (1) in a region satisfying 0.8 (&mgr;m)≦(a0−a)≦3.0 (&mgr;m): b0×(a/a0)3≦b(&mgr;m)≦b0×(a/a0)1/4  (1). Also disclosed are a process cartridge and an electrophotographic apparatus which have such an electrophotographic photosensitive member.
    Type: Grant
    Filed: December 18, 2002
    Date of Patent: November 9, 2004
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yosuke Morikawa, Tatsuya Ikezue, Kouichi Nakata, Kimihiro Yoshimura, Daisuke Tanaka
  • Publication number: 20040197689
    Abstract: A photoreceptor comprising a support layer and a photoconductive layer, wherein at least a portion of an exposed surface of the photoreceptor is roughened.
    Type: Application
    Filed: February 24, 2004
    Publication date: October 7, 2004
    Inventors: Benzion Landa, Mark Sandler
  • Patent number: 6790572
    Abstract: An electrophotographic photoreceptor including an electroconductive substrate, a photosensitive layer located overlying the electroconductive substrate, and optionally a protective layer overlying the photosensitive layer, wherein an outermost layer of the photoreceptor includes a filler, a binder resin and an organic compound having an acid value of from 10 to 700 mgKOH/g. The photosensitive layer can be the outermost layer. A coating liquid for an outermost layer of a photoreceptor including a filler, a binder resin, an organic compound having an acid value of from 10 to 700 mgKOH/g and plural organic solvents. A method for preparing a photoreceptor including forming a photosensitive layer, and coating the coating liquid on the photosensitive layer. An image forming method and apparatus and a process cartridge using the photoreceptor are also provided.
    Type: Grant
    Filed: November 2, 2001
    Date of Patent: September 14, 2004
    Assignee: Ricoh Company Limited
    Inventors: Nozomu Tamoto, Tetsuro Suzuki, Hiroshi Tamura, Tatsuya Niimi, Akihiko Matsuyama, Eiji Kurimoto, Hidetoshi Kami
  • Publication number: 20040063014
    Abstract: According to the present invention, there is provided: an electrophotographic photosensitive member having a photosensitive layer on a support in which a surface layer of the electrophotographic photosensitive member comprises an acrylic polymer having a polyfluoroolefin unit and an alkylene oxide unit, and having a number-average molecular weight in a range of 2,000 to 20,000; a process cartridge and an electrophotographic apparatus both comprising the electrophotographic photosensitive member.
    Type: Application
    Filed: July 15, 2003
    Publication date: April 1, 2004
    Inventors: Kimihiro Yoshimura, Yosuke Morikawa, Tatsuya Ikezue, Kouichi Nakata, Shuji Ishii, Daisuke Tanaka
  • Patent number: 6686109
    Abstract: In an electrophotographic process using an amorphous silicon photosensitive member which has a surface protective layer and effecting reverse development and cleaning with a cleaning blade, the surface moving speed PS (mm/sec) of the photosensitive member is 320 mm/sec or more and a film thickness and a specific resistance value of the surface protective layer are respectively Ds (&mgr;m) and Rs (&OHgr;·cm) which fulfill the following conditions: 1.0×109≦Rs≦1.0×1013 Ds≦−0.136Ln(Rs)+(−0.004×PS+6).
    Type: Grant
    Filed: March 27, 2002
    Date of Patent: February 3, 2004
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hideaki Matsuoka, Yoshio Segi, Hiroyuki Katagiri, Tetsuya Karaki
  • Patent number: 6649314
    Abstract: A process for reducing image defects in an electrostatographic image resulting from particulate contamination. A primary imaging member, including a photoconductive element and an outermost layer of silicon carbide, is uniformly charged in an electrostatographic imaging apparatus subject to particulate contamination. The electrostatographic imaging apparatus includes a charging station, an exposing station, at least one developing station, and a transfer station comprising an electrically biased roller transfer assembly. The primary imaging member is exposed imagewise at the exposing station to form a latent image on the imaging member, which is thereafter developed with toner at the developing station to form a developed image on the imaging member.
    Type: Grant
    Filed: February 17, 2000
    Date of Patent: November 18, 2003
    Assignee: NexPress Solutions LLC
    Inventors: Susan A. Visser, Donald S. Rimai, Paul M. Borsenberger
  • Publication number: 20030113646
    Abstract: An imaging method utilizing an imaging member containing a supporting substrate, a layer of a charge carrier injecting surface, a hole blocking layer, an optional adhesive layer, a layer of a charge carrier transport material, a layer of an charge carrier generating material, an optional charge trapping layer, a crossed linked silicone rubber, and an electrically insulating overcoating layer. The member is first charged with electrostatic charges of a first polarity, charged a second time with electrostatic charges of a polarity opposite to said first polarity in order to substantially neutralize the charges residing on the electrically insulating surface of the member and exposed to an imagewise pattern of activating electromagnetic radiation whereby an electrostatic latent image is formed. The electrostatic latent image may be developed to form a visible image which may be transferred to a receiver member. The imaging member may be reused after erasure and cleaning.
    Type: Application
    Filed: December 14, 2001
    Publication date: June 19, 2003
    Applicant: Xerox Corporation
    Inventors: Merlin E. Scharfe, Richard L. Schank, William W. Limburg, Damodar M. Pai, Dale S. Renfer, John F. Yanus, Paul J. DeFeo
  • Patent number: 6576388
    Abstract: An electrophotographic photoreceptor including at least an electroconductive substrate; and a photosensitive layer overlying the electroconductive substrate and including at least a charge generation layer; a charge transport layer; and a protective layer including a filler, wherein the filler is dispersed in the protective layer so as to occupy an area of from 3 to 5% of a cross section of the protective layer; the filler has particle diameter distribution having a peak at a diameter of from 0.2 to 0.3 &mgr;m; and the particles of the filler having a particle diameter of not less than 0.3 &mgr;m occupies an area of from 10 to 30% of the area of all the filler in the cross section of the protective layer.
    Type: Grant
    Filed: November 2, 2001
    Date of Patent: June 10, 2003
    Assignee: Ricoh Company Limited
    Inventors: Yohta Sakon, Akio Kosuge, Tatsuya Niimi, Narihito Kojima
  • Patent number: 6562530
    Abstract: An electrophotographic photosensitive member has, in this order, a support, a photosensitive layer and a protective layer. The thickness d (&mgr;m) of the protective layer, the universal hardness Hu-1 (N/mm2) of the protective layer, and the universal hardness Hu-2 (N/mm2) of the photosensitive layer after peeling off the protective layer satisfy the following expression (1): 5.8×d+Hu-2≦Hu-1≦−2.45×d2+44.4×d+Hu-2  (1). Also disclosed are a process cartridge and an electrophotographic apparatus which have the above electrophotographic photosensitive member.
    Type: Grant
    Filed: June 19, 2001
    Date of Patent: May 13, 2003
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yosuke Morikawa, Kouichi Nakata, Kimihiro Yoshimura, Daisuke Tanaka
  • Patent number: 6558862
    Abstract: An electrophotographic photoreceptor including a photosensitive layer on an electroconductive substrate, wherein nitrate ion is present on the surface of the photosensitive layer in an amount of from 50 to 300 &mgr;g per 1 m2 of the surface of the photosensitive layer when the nitrate ion is determined by an ion chromatographic method. Preferably a material having a fluorine atom and a carbon atom or a fatty acid metal salt such as zinc stearate is further present on the surface of the photosensitive layer such that the F/C ratio is from 0.05 to 0.5 or the Zn/C ratio is from 0.001 to 0.1. An image forming apparatus using the photoreceptor is also provided.
    Type: Grant
    Filed: March 2, 2001
    Date of Patent: May 6, 2003
    Assignee: Ricoh Company Limited
    Inventors: Narihito Kojima, Ryuta Takeichi, Akiyo Namiki, Hiroshi Nagame, Yohta Sakon
  • Publication number: 20030077531
    Abstract: An electrophotographic photoreceptor in which at least a photosensitive layer is provided above an electroconductive substrate, the outermost surface layer of the electroconductive substrate contains at least an inorganic filler, a binder resin, and an aliphatic polyester, or, alternatively, the outermost surface layer of the electroconductive substrate contains at least an inorganic filler and a binder resin and the binder resin is a copolymer polyarylate having an alkylene-arylcarboxylate structural unit, also an image forming method, image forming apparatus, and image forming apparatus processing unit in which the electrophotographic photoreceptor is used.
    Type: Application
    Filed: March 25, 2002
    Publication date: April 24, 2003
    Inventors: Tetsuro Suzuki, Kazukiyo Nagai, Nozomu Tamoto, Eiji Kurimoto, Hidetoshi Kami
  • Patent number: 6548218
    Abstract: Magnetic particles for charging means disposed in contact with an electrophotographic photosensitive member for charging the electrophotographic photosensitive member based on a voltage applied thereto are provided as particles of a ferrite component represented by the following formula (1): (Fe2O3)X(A)Y(B)Z  (1), wherein A denotes at least one metal oxide component selected from the group consisting of Li2O, MnO and MgO, B denotes at least one metal oxide component different from A; X, Y and Z denote numbers representing mol ratios and satisfying the following conditions: 0.2<X<0.95, 0.01<Y<0.5, X+Y≦1, and 0≦Z<0.79. The magnetic particles show an excellent charging performance, particularly in injection charging, without causing a difficulty, such as soiling or pinhole leakage of the photosensitive member.
    Type: Grant
    Filed: June 19, 1995
    Date of Patent: April 15, 2003
    Assignee: Canon Kabushiki Kaisha
    Inventors: Tsutomu Kukimoto, Kenji Okado, Shuichi Aita, Tsuyoshi Takiguchi
  • Publication number: 20030054272
    Abstract: A photoreceptor with good mechanical and physical properties is provided with an overcoat layer comprising a copolymer of an &agr;,&bgr;-ethylenically unsaturated carboxylic acid and an &agr;,&bgr;-ethylenically unsaturated monomer wherein the weight percent of the &agr;,&bgr;-ethylenically unsaturated carboxylic-acid is at least 25% up to 99% of the copolymer. The copolymer may comprise an &agr;,&bgr;-ethylenically unsaturated carboxylic acid and an &agr;,&bgr;-ethylenically unsaturated monomer wherein the copolymer has an acid value of at least 150 mg KOH/g the copolymer. The copolymer may be present in a blend with a second polymer or copolymer comprised of units derived from a second &agr;,&bgr;-ethylenically unsaturated monomer that is different from the an &agr;,&bgr;-ethylenically unsaturated carboxylic acid and/or the &agr;,&bgr;-ethylenically unsaturated monomer.
    Type: Application
    Filed: June 10, 2002
    Publication date: March 20, 2003
    Applicant: Samsung
    Inventors: Jiayi Zhu, Zbigniew Tokarski, Ronald J. Moudry, Kristine A. Fordahl, David T. Ask, Jonas Sidaravicius, Edmundas Montrimas, Kam W. Law, Valentas Gaidelis
  • Publication number: 20030049556
    Abstract: In an electrophotographic process using an amorphous silicon photosensitive member which has a surface protective layer and effecting reverse development and cleaning with a cleaning blade, the surface moving speed PS (mm/sec) of the photosensitive member is 320 mm/sec or more and a film thickness and a specific resistance value of the surface protective layer are respectively Ds (&mgr;m) and Rs (&OHgr;·cm) which fulfill the following conditions:
    Type: Application
    Filed: March 27, 2002
    Publication date: March 13, 2003
    Inventors: Hideaki Matsuoka, Yoshio Segi, Hiroyuki Katagiri, Tetsuya Karaki
  • Publication number: 20030050489
    Abstract: A method for purifying an electronic item material, which comprises dissolving an electronic item material or its intermediate product in an organic solvent and having the solution contacted with activated clay at a temperature of 65° C. to 200° C.
    Type: Application
    Filed: June 29, 2001
    Publication date: March 13, 2003
    Applicant: Hodogaya Chemical Co., Ltd.
    Inventors: Katsumi Abe, Tomonori Nishimura, Takanobu Watanabe, Susumu Suzuka
  • Patent number: 6531253
    Abstract: An a-Si photosensitive member and an image forming apparatus are provided which prevent fusion bonding in digital copying machines and attain satisfactory image formation. Specifically, in order that even when uneven abrasion occurs on a drum surface layer, it may not substantially affect the image, a photosensitive member formed by successively stacking on a conductive substrate a photoconductive layer comprising amorphous Si and a surface protective layer comprised of an amorphous material is provided such that the spectral reflectance (%) satisfies the relation of 0≦(Max−Min)/(Max+Min)≦0.20, and a center line average roughness Ra1 of the interface on the surface side of the photoconductive layer and the center line average roughness Ra2 of the outermost surface of the surface layer, within the range of 10 &mgr;m×10 &mgr;m, satisfy the relations of Ra1/Ra2≧1.3 and 22 nm≦Ra1≦100 nm.
    Type: Grant
    Filed: March 29, 2001
    Date of Patent: March 11, 2003
    Assignee: Canon Kabushiki Kaisha
    Inventors: Toshiyuki Ehara, Koji Yamazaki, Masaya Kawada, Tetsuya Karaki, Hironori Ohwaki, Kunimasa Kawamura
  • Patent number: 6517984
    Abstract: An electrophotographic element comprises: an electrically conducting layer, a charge generating layer overlying the electrically conducting layer, and a charge transport layer overlying the electrically conducting layer. The charge transport layer, which can be an overcoat overlying the charge generating layer, comprises the reaction product in an aqueous medium of a mixture comprising a silsesquioxane polymer and a hole transport compound that comprises a tertiary arylamine containing at least one alcoholic or one phenolic hydroxy substituent.
    Type: Grant
    Filed: March 27, 2001
    Date of Patent: February 11, 2003
    Assignee: Heidelberger Druckmaschinen AG
    Inventors: Wayne Thomas Ferrar, Jane Robinson Cowdery-Corvan, William Tod Gruenbaum, Jeanne Ellen Kaeding, Michel Frantz Molaire, Louis Joseph Sorriero, David Steven Weiss
  • Patent number: 6503674
    Abstract: Member for a printer, a fax machine, a copier or a toner cartridge, in which said member has a face in contact with toner particles, said face being provided with a top layer in contact with toner particles, said top layer comprising substantially spherical particles with a Mohs hardness of more than 3 or equal to 3 and an average particle size lower than 100 &mgr;m.
    Type: Grant
    Filed: April 24, 2001
    Date of Patent: January 7, 2003
    Assignee: CF Technologies
    Inventor: Gino Sirejacob
  • Publication number: 20020197549
    Abstract: An electrophotographic photoreceptor including at least an electroconductive substrate; and a photosensitive layer overlying the electroconductive substrate and including at least a charge generation layer; a charge transport layer; and a protective layer including a filler, wherein the filler is dispersed in the protective layer so as to occupy an area of from 3 to 5% of a cross section of the protective layer; the filler has particle diameter distribution having a peak at a diameter of from 0.2 to 0.3 &mgr;m; and the particles of the filler having a particle diameter of not less than 0.3 &mgr;m occupies an area of from 10 to 30% of the area of all the filler in the cross section of the protective layer.
    Type: Application
    Filed: November 2, 2001
    Publication date: December 26, 2002
    Inventors: Yohta Sakon, Akio Kosuge, Tatsuya Niimi, Narihito Kojima
  • Patent number: 6492081
    Abstract: An electrophotographic photosensitive member exhibiting a good durability and stable electrophotographic performances regardless of environmental change is provided by coating the photosensitive layer with a specific protective layer. The protective layer has a thickness of 1-7 &mgr;m and comprises a cured phenolic resin and metal particles or metal oxide particles dispersed therein.
    Type: Grant
    Filed: June 19, 2001
    Date of Patent: December 10, 2002
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yosuke Morikawa, Kouichi Nakata, Hiroshi Saito
  • Patent number: 6489069
    Abstract: An electrophotographic image carrier is disclosed. The image carrier has a photoreceptor made from a photoreceptive layer and a resin layer. The resin layer is made of a siloxane resin having a cross-linked structure, and contains an anti-oxidant.
    Type: Grant
    Filed: February 9, 2000
    Date of Patent: December 3, 2002
    Assignee: Konica Corporation
    Inventors: Akihiko Itami, Takeo Oshiba, Tomoo Sakimura, Yohko Kitahara, Masahiko Kurachi, Kazuhisa Shida
  • Patent number: 6489071
    Abstract: The invention relates to an electrophotosensitive material comprising an organic photosensitive layer and an inorganic surface protective layer, wherein at least an outermost part of the organic photosensitive layer contains a diphenylamine compound represented by a formula (1): wherein ‘A’ denotes a groups combined with two phenyl groups in the formula in a manner to jointly form a &pgr;-electron conjugated system. The electrophotosensitive material features more excellent durability because the compound functions as a binder for combining the organic photosensitive layer with the inorganic surface protective layer so that the surface protective layer is less prone to suffer cracks or delamination.
    Type: Grant
    Filed: July 24, 2001
    Date of Patent: December 3, 2002
    Assignee: Kyocera Mita Corporation
    Inventors: Eiichi Miyamoto, Yoshio Inagaki, Hideaki Fukunaga
  • Publication number: 20020177058
    Abstract: Member for a printer, a fax machine, a copier or a toner cartridge, in which said member has a face in contact with toner particles, said face being provided with a top layer in contact with toner particles, said top layer comprising substantially spherical particles with a Mohs hardness of more than 3 or equal to 3 and an average particle size lower than 100 &mgr;m.
    Type: Application
    Filed: April 24, 2001
    Publication date: November 28, 2002
    Inventor: Gino Sirejacob
  • Publication number: 20020159804
    Abstract: Disclosed are image forming apparatus [1] which comprises removing a toner remained on the surface of the rotatable image carrier by cleaning means after going through developing means and transferring means; said cleaning means has an elastic blade and is contacted with the surface of the image carrier at a contact pressure within 8 to 20 g/cm, and a press-contact angle of the elastic blade of 12 to 30°; and said image carrier is an organic photosensitive material having a photosensitive layer made of a binder resin containing an electric charge generating material and an electric charge transferring material; and image forming apparatus [2], comprising a single-layer type photosensitive layer made of a binder resin containing an electric charge generating material, an electron transferring material and a hole transferring material, and the solid content of the binder resin is within 50 to 70 wt % of the whole solid content in the photosensitive layer and, a pair of paper transporting
    Type: Application
    Filed: February 14, 2002
    Publication date: October 31, 2002
    Inventors: Jun Azuma, Ayako Yashima, Yukimasa Watanabe, Keisuke Oba, Masashi Fujishima, Takashi Nagashima
  • Patent number: 6447966
    Abstract: This invention is to provide an electrophotographic photosensitive body used in a wet electrophotographic apparatus and including a substrate having a conductive surface, and a photosensitive layer formed on the conductive surface of the substrate and changing in a charged state upon being irradiated with light, the photosensitive layer having, on an exposed surface, C—F bonds and C—H bonds for which the ratio of the number NCF of C—F bonds to the number NCH of C—H bonds satisfies, on the exposed surface of the photosensitive layer, a relationship represented by 2/100<NCF/NCH<300/100, and a wet electrophotographic apparatus using the electrophotographic photosensitive body.
    Type: Grant
    Filed: March 9, 2000
    Date of Patent: September 10, 2002
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hitoshi Yagi, Masahiro Hosoya, Koichi Ishii
  • Patent number: 6444387
    Abstract: An image bearing material including a matrix resin and, within the matrix resin, a core/shell graft copolymer including a core including one or more polymers and a shell including a graft polymer which has a linear chain connected with the core and which is formed from one or more monomers. The image bearing material is preferably used for a surface layer of an electrophotographic photoreceptor, an intermediate transfer medium, and the like image bearing members to improve the abrasion resistance thereof.
    Type: Grant
    Filed: December 22, 2000
    Date of Patent: September 3, 2002
    Assignee: Ricoh Company Limited
    Inventors: Kohkoku Ri, Masaomi Sasaki, Kazukiyo Nagai, Shinichi Kawamura
  • Patent number: 6436597
    Abstract: An electrophotographic photosensitive member has a support and a photosensitive layer formed thereon. The electrophotographic photosensitive member has a surface layer containing a charge-transporting material and a resin obtained by exposing to radiations a compound having an acryloyloxy group or methacryloyloxy group to cure.
    Type: Grant
    Filed: January 6, 1999
    Date of Patent: August 20, 2002
    Assignee: Canon Kabushiki Kaisha
    Inventors: Akio Maruyama, Shoji Amamiya, Michiyo Sekiya, Hiroki Uematsu
  • Patent number: 6406825
    Abstract: An electrophotographic photoreceptor is disclosed. The photoreceptor comprises a resin layer &bgr; obtained by hardening at least one of an organic silicon compound having a hydroxyl group or a hydrolizable group and condensation compound thereof, and a compound represented by formula(1), A(Q)k  (1) wherein A represents a group containing an aromatic group or a heterocyclic group, Q represents a group containing at least one of a hydroxy group, an amino group, and a mercapto group, and k represents an integer not less than 2, and wherein said organic silicon compound is three-dimensionally cross-linked.
    Type: Grant
    Filed: October 17, 2000
    Date of Patent: June 18, 2002
    Assignee: Konica Corporation
    Inventors: Tomoo Sakimura, Akihiko Itami, Kazumasa Watanabe, Shingo Fujimoto, Toyoko Shibata, Tomoko Sakimura
  • Patent number: 6408152
    Abstract: A process cartridge is disclosed which includes an electrophotographic photosensitive member having a photosensitive layer and a charging means. The charging means has a charging member which is provided in contact with the electrophotographic photosensitive member to charge the photosensitive member electrostatically by applying a voltage formed by superimposing an alternating-current voltage on a direct-current voltage. The photosensitive member has a surface layer which contains at least one of a polyarylate resin having a weight-average molecular weight of 7.5×103 to 3.7×104 and having a specific structural unit of Formula (1) and a polycarbonate resin having a weight-average molecular weight of 7.5×103 to 3.7×104 and having a specific structural unit of Formula (2). The photosensitive member further contains fluorine-containing resin particles. Also, an electrophotographic apparatus having the photosensitive member is disclosed.
    Type: Grant
    Filed: April 28, 1999
    Date of Patent: June 18, 2002
    Assignee: Canon Kabushiki Kaisha
    Inventors: Wataru Kitamura, Osamu Tamura, Yoshihisa Saito
  • Patent number: 6406824
    Abstract: As the surface layers of an electrophotographic photosensitive member, a first surface layer which satisfies a condition that a center line average surface roughness (Ra) ranges from 50 Å to 5000 Å and a second surface layer comprising a non-single-crystal carbon containing at least fluorine are laminated in this order. Thus, the generation of a defective image such as the dimness of an image or an image smearing can be suppressed under an environment of high temperature and high humidity without providing any heater even when an electrophotographic apparatus is repeatedly employed. Further, even when a toner of small particle size and excellent in its fixing characteristic is used, a cleaning characteristic can be improved and the fusion of the toner can be suppressed. Still further, even in an electrophotographic process with a frictional force raised for improving the cleaning characteristic, the cleaning characteristic can be improved and the fusion of the toner can be suppressed.
    Type: Grant
    Filed: November 24, 1999
    Date of Patent: June 18, 2002
    Assignee: Canon Kabushiki Kaisha
    Inventors: Ryuji Okamura, Shigenori Ueda, Junichiro Hashizume
  • Patent number: 6405005
    Abstract: A process cartridge is disclosed which includes an electrophotographic photosensitive member having a photosensitive layer and a charging means. The charging means has a charging member which is provided in contact with the electrophotographic photosensitive member to charge the photosensitive member electrostatically by applying a voltage formed by superimposing an alternating-current voltage on a direct-current voltage. The photosensitive member has a surface layer which contains at least one of a polyarylate resin having a weight-average molecular weight of 7.5×103 to 3.7×104 and having a specific structural unit of Formula (1) and a polycarbonate resin having a weight-average molecular weight of 7.5×103 to 3.7×104 and having a specific structural unit of Formula (2). The photosensitive member further contains fluorine-containing resin particles. Also, an electrophotographic apparatus having the photosensitive member is disclosed.
    Type: Grant
    Filed: July 31, 2000
    Date of Patent: June 11, 2002
    Assignee: Canon Kabushiki Kaisha
    Inventors: Wataru Kitamura, Osamu Tamura, Yoshihisa Saito
  • Patent number: 6395441
    Abstract: The present invention provides an electrophotographic photosensitive member having a surface layer containing diorganopolysiloxane having, as substituents, a perfluoro group, and a group having a substituted or unsubstituted polystyrene chain, a closed terminal and a degree of polymerization of 3 or more. The present invention also provides a process cartridge having the electrophotographic photosensitive member, and an electrophotographic apparatus.
    Type: Grant
    Filed: December 27, 2000
    Date of Patent: May 28, 2002
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hirotoshi Uesugi, Hideki Anayama
  • Publication number: 20020048711
    Abstract: The invention relates to an electrophotographic photosensitive member, and more specifically, to a photosensitive member having a photosensitive layer superimposed over a substrate. In one aspect of the invention, sequential laminations of a dispersion layer of conductive tantalum-doped tin oxide powder dispersed in a binder resin solution, are provided between the substrate layer and the photosensitive layer. Another aspect of the invention relates to a protective layer provided for the photosensitive layer. The protective layer of the most exterior surface of the photosensitive member may be a dispersion layer formed by dispersing tantalum-doped tin oxide powder in a resin solution.
    Type: Application
    Filed: September 19, 2001
    Publication date: April 25, 2002
    Applicant: Minolta Co., Ltd.
    Inventors: Kimiyuki Ito, Keiichi Inagaki, Takeshi Ishida
  • Patent number: 6372397
    Abstract: An electrophotographic photosensitive member is constituted by a support and a photosensitive layer disposed on the support. The photosensitive layer comprises a charge-transporting material and a resin obtained by radiation curing of a compound having a functional group represented by the following formula (1): wherein Ar denotes a substituted or unsubstituted arylene group and R1 denotes a hydrogen atom or methyl group.
    Type: Grant
    Filed: December 30, 1999
    Date of Patent: April 16, 2002
    Assignee: Canon Kabushiki Kaisha
    Inventors: Akio Maruyama, Toshihiro Kikuchi, Shoji Amamiya, Michiyo Sekiya, Hiroki Uematsu
  • Patent number: 6372398
    Abstract: The present invention relates to a manufacturing method of an electronic device comprising the steps of: preparing at least two kinds of hydrolytic silicon compounds that are different in reactivity to water; preparing a protective group precursor having a substituent having a reactivity to water equal or substantially equal to the reactivity of a reactive group of one of the hydrolytic silicon compounds to water; exchanging a reactive group of the other hydrolytic silicon compound with the substituent of the protective group precursor; preparing a silicon-containing coating agent containing the one of the hydrolytic silicon compounds and a hydrolytic silicon compound having the reactive group which has been exchanged with the substituent of the protective group precursor; and coating and curing the silicon-containing coating agent on a base plate so that at least one layer of a cured film is formed.
    Type: Grant
    Filed: November 28, 2000
    Date of Patent: April 16, 2002
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Wataru Yamada, Katsumi Nukada, Rie Ishii, Mieko Seki
  • Patent number: 6365308
    Abstract: In order to maintain excellent electrical, optical and photoconductive characteristics and to significantly improve the durability under adverse environments, a light receiving member for electrophotography according to the present invention comprises in sequence: a supporting member and a light receiving layer; said light receiving layer comprising in sequence at least a photoconductive layer and a surface layer thereon, said photoconductive layer comprising a non-single-crystal material containing silicon atoms as a matrix, and said surface layer comprising an amorphous material containing silicon atoms and carbon atoms as a matrix, wherein the carbon atoms are at least diamond-bonded and graphite-bonded, and wherein from 2% to 30% by number of the carbon atoms are graphite-bonded.
    Type: Grant
    Filed: October 29, 1997
    Date of Patent: April 2, 2002
    Assignee: Canon Kabushiki Kaisha
    Inventors: Satoshi Kojima, Keishi Saito, Hirokazu Ohtoshi, Masafumi Sano, Junichiro Hashizume, Yasuyoshi Takai, Ryo Hayashi, Masahiko Tonogaki
  • Patent number: 6365309
    Abstract: The present invention provided a photosensitive member for electrophotography having excellent durability and adhesion between a surface protective layer and a photosensitive layer. In the photosensitive member for electrophotography wherein at least the photosensitive layer and the surface protective layer are laminated on an electroconductive support in this order, the characteristic is that said surface protective layer comprises at least polysiloxane and silyl group-containing vinyl resin.
    Type: Grant
    Filed: February 1, 2000
    Date of Patent: April 2, 2002
    Assignee: Minolta Co., Ltd.
    Inventors: Shigeaki Tokutake, Keiichi Inagaki, Teiko Edo, Mitsutoshi Sakamoto
  • Publication number: 20020018953
    Abstract: An electrophotographic photosensitive member has a support and a photosensitive layer formed thereon. The electrophotographic photosensitive member has a surface layer containing a charge-transporting material and a resin obtained by exposing to radiations a compound having an acryloyloxy group or methacryloyloxy group to cure.
    Type: Application
    Filed: January 6, 1999
    Publication date: February 14, 2002
    Inventors: AKIO MARUYAMA, SHOJI AMAMIYA, MICHIYO SEKIYA, HIROKI UEMATSU
  • Patent number: 6342325
    Abstract: The main material of related photoconductors is silicon. When toner is blown onto a photoconductor, spots of NOx occur, which leads to occurrence of image blurring and image running, and image quality deteriorates substantially. In the present invention, there is provided a photoconductor for use in an electro-photographic photoconductor comprising a conductive substrate, a carrier blocking layer and a photosensitive layer, wherein a value for a polarized element of the most outer surface energy of the photoconductor is 2 [mN/cm] or less. The photoconductor can therefore be used without being heated to 35-45° C., heating equipment is unnecessary, and image blurring and image running do not occur. The present invention also includes defining of the most outer surface energy of the photoconductor having a surface protection layer composed mainly of silicon on the photosensitive layer.
    Type: Grant
    Filed: November 20, 2000
    Date of Patent: January 29, 2002
    Assignee: Stanley Electric Co., Ltd.
    Inventors: Fumiyuki Suda, Hiroaki Hamanaka, Shinichi Nomura