Patents Examined by Roland E. Martin
  • Electrophotographic image forming
    Patent number: 4921768
    Abstract: A photoconductive image forming method in a which charged toner contacts a transparent insulating substrate and is exposed from within the substrate. Exposure reduces the resistivity of the toner so that its charge can be reversed by a bias voltage and the exposed toner will adhere to the image forming substrate simultaneously with exposure and then transfer to a transfer medium. In an alternative embodiment of the invention, a layer of toner is applied to an electroconductive substrate and the toner layer is exposed with a latent image. The charge of the exposed toner is reversed and the exposed toner is removed by an intermediate toner removal device. The remaining toner is then transferred to a transfer medium. Toner suitable for use includes azo-type metal containing black dyes which do not absorb the exposure and can be sensitized to the near infrared region.
    Type: Grant
    Filed: October 5, 1988
    Date of Patent: May 1, 1990
    Assignee: Seiko Epson Corporation
    Inventors: Masanao Kunugi, Hajime Kurihara, Teruyuki Mizumoto
  • Image forming method
    Patent number: 4920035
    Abstract: An image is formed by imagewise exposing a silver halide light-sensitive material comprising at least a silver halide and a contrast enhancing agent, and producing the exposed material with a developer solution or aqueous activator solution in the presence of a substantially water-insoluble metal compound such as zinc hydroxide and a complexing compound such as guanidine picolinate.
    Type: Grant
    Filed: October 19, 1987
    Date of Patent: April 24, 1990
    Assignee: Fuji Photo Film Co., Ltd.
    Inventor: Katsumi Hayashi
  • Stable color developer compositions and process for the preparation thereof
    Patent number: 4920023
    Abstract: A process for the preparation of stable developer compositions, which comprises treating coated carrier particles with metal salts, or metal salts of fatty acids, and thereafter admixing these particles with a colored toner composition containing metal salts or metal salts of fatty acids, and comprised of resin particles and colored pigment particles, and wherein the salts are present in an amount of from about 0.01 to about 1 percent by weight.
    Type: Grant
    Filed: June 2, 1988
    Date of Patent: April 24, 1990
    Assignee: Xerox Corporation
    Inventors: Ronald J. Koch, John F. Knapp, Robert J. Gruber
  • Color image forming process comprising developing with substantially no benzyl alcohol a material having specific sensitizing dyes
    Patent number: 4920042
    Abstract: A color image-forming process of developing a color photographic paper having on a support silver halide emulsion layer(s) containing a monodispersed silver chlorobromide emulsion having a deviation coefficient of not more than 20% and a color coupler, said emulsion being spectrally sensitized by at least one of the compounds represented by general formulae (I), (II), (III) and (IV) defined in this invention, using a color developer containing substantially no benzyl alcohol for a period of time of not more than 2 minutes and 30 seconds.In processing the aforesaid color photographic paper, even when the color paper is procesed using a color developer containing no benzyl alcohol, which caused pollution problems, in a short processing time of not more than 2 minutes and 30 seconds, stable color images having less formation of fog and high color density are obtained.
    Type: Grant
    Filed: August 10, 1989
    Date of Patent: April 24, 1990
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Kokichi Waki, Masahiro Asami, Yoshinori Shibata
  • Photosensitive member composed of charge transporting layer and charge generating layer
    Patent number: 4913994
    Abstract: The practice of this invention provides a photosensitive member which comprises a charge transporting layer and a charge generating layer, said charge transporting layer essentially consists of a plasma-polymerized layer of amorphous material comprising methyl group and methylene group in the ratio of the number of the former to the number of the latter being 0.5:1 to 3:1. The photosensitive member obtained thereby is excellent in charge-transporting property and chargeability and, moreover, exhibits advantages corona resistance and resistances to acids, moisture and heat and also in physical properties such as stiffness.
    Type: Grant
    Filed: February 13, 1989
    Date of Patent: April 3, 1990
    Assignee: Minolta Camera Kabushiki Kaisha
    Inventors: Izumi Osawa, Shuji Iino, Hideo Hotomi, Mitsutoshi Nakamura
  • Gold sensitized silver halide emulsion and photographic silver halide light-sensitive material using same
    Patent number: 4914017
    Abstract: A gold-sensitized silver halide emulsion of surface latent image type exhibits improved shelf stability while maintaining high sensitivity when at least 80% of the gold sensitizer is contained in the silver halide grain phase. A photographic silver halide light-sensitive material is prepared as comprising at least one emulsion layer which contains the improved silver halide emulsion.
    Type: Grant
    Filed: June 16, 1987
    Date of Patent: April 3, 1990
    Assignee: Fuji Photo Film Co., Ltd.
    Inventor: Hiroyuki Mifune
  • Two-layer system
    Patent number: 4914004
    Abstract: Radiation-curable two-layer systems containing immobilized photoinitiators are suitable for the production of coatings of constant thickness and good adhesion, and relief structures of high resolution and edge steepness.
    Type: Grant
    Filed: August 28, 1987
    Date of Patent: April 3, 1990
    Assignee: Merck Patent Gesellschaft Mit Beschrankter Haftung
    Inventors: Manfred Kohler, Eike Poetsch, Jorg Ohngemach, Dieter Dorsch, Rudolf Eidenschink, Gerhard Greber
  • Photosensitive member composed of charge transporting layer and charge generating layer
    Patent number: 4913993
    Abstract: The practice of this invention provides a photosensitve member which comprises a charge transporting layer and a charge generating layer, said charge transporting layer essentially consisting of plasma-polymerized layer of amorphous material having carbon atoms constituting methyl group in a ratio of 20 to 60% against all the carbon atoms therein. The photosensitve member obtained thereby is excellent in charge-transporting property and chargeability and, moreover, exhibits advantages in corona resistance and resistances to acids, moisture and heat and also in physical properties such as stiffness.
    Type: Grant
    Filed: February 13, 1989
    Date of Patent: April 3, 1990
    Assignee: Minolta Camera Kabushiki Kaisha
    Inventors: Izumi Osawa, Shuji Iino, Hideo Hotomi, Mitsutoshi Nakamura
  • Electrophotographic process using fluorine resin coated heat application roller
    Patent number: 4913991
    Abstract: An electrographic process comprising the steps of forming latent electrostatic images on a photoconductive material, developing the latent electrostatic images with a toner to toner images, transferring the toner images to a recording sheet, fixing the toner images to the recording sheet by causing the toner image bearing recording sheet to pass between a heat application roller coated with a fluorine-containing resin and a pressure application roller for fixing to the toner images to the recording sheet, in which electrographic process the rheological characteristics of the toner are such that the loss tangent (tan .delta.), which is a ratio of the loss moldus (G") to the storage modulus (G') of the toner, is in the range of 1.70 to 3.00 when the storage modulus (G') is 10.sup.5 dynes/cm.sup.2, namely1.70.ltoreq.tan .delta..ltoreq.3.
    Type: Grant
    Filed: April 15, 1988
    Date of Patent: April 3, 1990
    Assignee: Ricoh Company, Ltd.
    Inventors: Shunichi Chiba, Satoru Inoue, Akio Matsui, Yoshihisa Okamoto
  • Disazo electrophotographic photoreceptor
    Patent number: 4913997
    Abstract: This provides an electrophotographic photoreceptor high in durability and sensitivity which comprises an electroconductive support and, provided thereon, a photosensitive layer containing an azo pigment represented by the formula [I]: ##STR1## wherein A represents an aryl group, a heterocyclic group or an alkyl group, Z represents a hydrogen atom, --B or --CH.dbd.CH--B wherein B represents an aryl group, a heterocyclic group or an alkyl group and Cp represents a coupler residue.
    Type: Grant
    Filed: January 12, 1989
    Date of Patent: April 3, 1990
    Assignee: Mitsubishi Paper Mills Limited
    Inventors: Kazuhiro Emoto, Kozo Haino
  • Light-sensitive material comprising light-sensitive layer provided on support where layer has specified ph
    Patent number: 4913999
    Abstract: A light-sensitive material comprises a light-sensitive layer containing silver halide, a reducing agent and a polymerizable compound provided on a paper support, wherein the paper support comprises a coating layer containing a hydrophobic polymer and a pigment provided on a base paper sheet. The coating layer has a pH value in the range of 4 to 9.
    Type: Grant
    Filed: January 29, 1988
    Date of Patent: April 3, 1990
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Shigehisa Tamagawa, Masayuki Kuroishi
  • Electrostatic toner
    Patent number: 4912006
    Abstract: An electrostatic toner consists of a polymer a charge controlling component and an optional color-giving component, wherein the charge controlling agent component comprises one or more compounds of the formula `(I)`, ##STR1## ps where R.sup.1 is chlorine or methyl, R.sup.2 is C.sub.4 -C.sub.22 -alkyl, benzyl or 2-phenylethyl, A.THETA. is an anion, n is 0, 1 or 2, m is 1 or 2 and r is 1 or 2.
    Type: Grant
    Filed: June 16, 1989
    Date of Patent: March 27, 1990
    Assignee: BASF Aktiengesellschaft
    Inventors: Walter Breitschaft, Erwin Czech, Udo Mayer, Guenther Seybold, Horst Bruder, Rainer Dyllick-Brenzinger
  • High contrast photographic recording material and emulsion and process for their development
    Patent number: 4912016
    Abstract: A photographic recording material and emulsion are described which are capable of providing high contrast images. The recording material and emulsion comprises negative working silver halide and contrast enhancing arylhydrazide nucleating agents. A process for utilization of the elements and emulsions is also described.
    Type: Grant
    Filed: May 31, 1988
    Date of Patent: March 27, 1990
    Assignee: Eastman Kodak Company
    Inventors: Harold I. Machonkin, Lee J. Fleckenstein, Donald L. Kerr
  • Electrophotographic photoreceptor
    Patent number: 4912000
    Abstract: An electrophotographic photoreceptor comprises an electrically conductive support, a photoconductive layer provided thereon, and a protective layer coated on the photoconductive layer, wherein the protective layer comprises a product of uncatalized hydrolysis of a composition essentially consisting of at least one specific epoxysilane compound, at least one specific alkylalkoxysilane compound, and at least one specific aminosilane compound. The photoreceptor is very useful in that it is free from wear due to friction with paper and cleaning members, keeps high resolving power, and is sufficiently proof against continuous copying under conditions of high temperature and high humidity.
    Type: Grant
    Filed: January 30, 1989
    Date of Patent: March 27, 1990
    Assignees: Japan Atomic Energy Research Institute, Shindengen Electric Manufacturing Co., Yamanashi Electronics Co., Ltd.
    Inventors: Minoru Kumakura, Isao Kaetsu, Masahiro Horigome, Tsuneo Isomura, Tomio Yoneyama, Tadaichi Murata
  • Method of annealing electrophotographic photosensitive device
    Patent number: 4912008
    Abstract: In an electrophotographic photosensitive device, which comprises an electroconductive support, a photoconductive layer provided thereon, and a surface protective layer provided on the photoconductive layer, the surface protective layer being made from a film having a density of localized states of not more than 5.times.10.sup.17 cm.sup.-3 and a higher dark resistance than that of the photoconductive layer, the surface protective layer is less susceptible to deterioration, adhesion to the photoconductive layer is enhanced, and thus the device has a prolonged life.
    Type: Grant
    Filed: May 31, 1988
    Date of Patent: March 27, 1990
    Assignee: Hitachi, Ltd.
    Inventors: Megumi Naruse, Kunihiro Tamahashi, Mitsuo Chigasaki, Masanobu Hanazono
  • Toner and developer compositions with conductive carrier components
    Patent number: 4912005
    Abstract: A carrier composition with a conductivity of from about 10.sup.4 to about 10.sup.10 (ohm-cm).sup.-1, and comprised of a mixture of a first carrier component and a second carrier component, at least one of said carrier components containing a polymeric coating thereover, and wherein at least one coating contains conductive particles.
    Type: Grant
    Filed: January 26, 1989
    Date of Patent: March 27, 1990
    Assignee: Xerox Corporation
    Inventors: Donald J. Goodman, John F. Knapp
  • Image forming method using toner of pH 2.5-6.5
    Patent number: 4912007
    Abstract: An image forming method wherein an electrostatic latent image formed on a photosensitive member having an organic plasma polymerized layer formed on the surface of the member is developed by using a toner having a pH of about 2.5 to 6.5. By this method, a sharp and clear image can be obtained over a long period of time.
    Type: Grant
    Filed: July 15, 1988
    Date of Patent: March 27, 1990
    Assignee: Minolta Camera Kabushiki Kaisha
    Inventors: Izumi Osawa, Kenji Masaki
  • Reverse development method
    Patent number: 4912003
    Abstract: A reverse development method comprising the steps of forming electrostatic image on the surface of an image-bearing member; supplying a developer comprising chargeable magnetic toner based on magnetic powder and a resin development roll comprising a conductive core, a permanent magnet arranged around the conductive core and a dielectric layer provided around and fixed to the permanent magnet and having conductive particles mutually insulated from each other; conveying the developer onto a surface of the image-bearing member by rotation of the developement roll so that the magnetic toner is attracted to the uncharged portions of the image; characterized in that the chargeable magnetic toner contains an aliphatic acid metal salt and is coated with hydrophobic silica.
    Type: Grant
    Filed: August 23, 1988
    Date of Patent: March 27, 1990
    Assignee: Hitachi Metals, Ltd.
    Inventors: Masumi Asanae, Fumio Kimura
  • Toner for electrophotography
    Patent number: 4910114
    Abstract: A toner for electrophotography containing as a binder a polymer comprising as essential ingredient a high-molecular-weight monofunctional monomer having a weight average molecular weight of 1,000 to 50,000 and an ethylenic double bond only at one end of the molecular chain is excellent in fixing properties in a heat roll fixing process and anti-offset properties.
    Type: Grant
    Filed: May 4, 1987
    Date of Patent: March 20, 1990
    Assignee: Hitachi Chemical Company, Ltd.
    Inventors: Yukihisa Hosino, Takeo Kudo
  • Photoreceptor for electrophotography
    Patent number: 4908289
    Abstract: Novel squarylium compounds, a process for the production thereof as well as to a photoreceptor for electrophotography containing the squarylium compound are disclosed, said squarylium compounds being represented by formula (I) or (II): ##STR1## wherein X is a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, a hydroxyl group, an alkoxy group having 1 to 4 carbon atoms, or a halogen atom; Y is a hydrogen atom, an alkyl group having 1 to 4 carbon atoms a hydroxyl group or an alkoxyl group having 1 to 4 carbon atoms.
    Type: Grant
    Filed: December 17, 1986
    Date of Patent: March 13, 1990
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Hiroyuki Tanaka, Seki Kin, Lyong S. Pu