Patents Examined by Roland Martin
  • Patent number: 7879520
    Abstract: A toner for developing an electrostatic image comprises a binding resin for a toner and a charge control agent including an azo-type iron complex salt represented by the following chemical formula (1) (in the chemical formula (1), R1 and R3 are the same or different to each other and are an alkyl group having a straight chain or a branch chain of 3 to 8 carbons; R2a, R2b, R4a and R4b are the same or different to each other and are selected from the group consisting of a hydrogen atom, an alkyl group, an alkoxyl group, a halogen atom, a nitro group and a carboxyl group; A+ indicates m(H+)+n(K+)+p(Na+), which m, n and p satisfy numerical equations of m+n+p=1, 0.7?m?1, 0?n?0.3 and 0?p?0.3), wherein an average particle size thereof is 1 to 4 microns, and a specific volume resistivity thereof is ranging from 0.2×1015 to 7×1015 ?·cm.
    Type: Grant
    Filed: June 5, 2007
    Date of Patent: February 1, 2011
    Assignee: Orient Chemical Industries, Ltd.
    Inventors: Kaori Sato, Masashi Yasumatsu
  • Patent number: 7838187
    Abstract: The presently disclosed embodiments are directed to charge transport layers useful in electrostatography. More particularly, the embodiments pertain to an improved electrostatographic imaging member having a charge transport layer that is dual-dopant, wherein operating life improvement is achieved by incorporating a small amount of compatible thermalsetting resin and polyhedral oligomeric silsesquioxane into the layer. Incorporation of these resins have been shown to increase charge transport life.
    Type: Grant
    Filed: August 21, 2007
    Date of Patent: November 23, 2010
    Assignee: Xerox Corporation
    Inventors: Liang-Bih Lin, Daniel V. Levy, Jin Wu, Robert W. Hedrick, Gary A. Batt, M. John Hinckel
  • Patent number: 6410198
    Abstract: The present invention relates to a novel zirconium compound which is useful as a charge control agent for an electrophotographic toner. Further, it relates to an electrophotographic toner which contains said zirconium compound as a charge control agent.
    Type: Grant
    Filed: May 4, 1999
    Date of Patent: June 25, 2002
    Assignee: Hodogaya Chemical Co., Ltd.
    Inventors: Masataka Sawano, Taito Muraoka, Katuya Yamaguti, Rie Murakami, Hiroyoshi Yamaga
  • Patent number: 6331372
    Abstract: Toner particulates include a first resin comprising a cross-linked copolymer; a second resin comprising a non-cross-linked copolymer; and a wax comprising an ethylene propylene copolymer. The cross-linked copolymer is a copolymer other than the wax comprising an ethylene propylene copolymer and the non-cross-linked polymer is a copolymer other than the wax comprising an ethylene propylene copolymer.
    Type: Grant
    Filed: October 8, 1999
    Date of Patent: December 18, 2001
    Assignee: Lexmark International, Inc.
    Inventors: Bryan Patrick Livengood, James Craig Minor, Michael Thomas Moore, John Melvin Olson, Minerva Piffarerio, Vincent Wen-Hwa Ting
  • Patent number: 6294305
    Abstract: An image forming method includes (i) a charging step of using a charging device including conductive magnetic particles, a rotatable conductive-magnetic-particle carrying member for carrying and conveying the conductive magnetic particles, and a plurality of magnetic-field generation means provided within the conductive-magnetic-particle carrying member, and charging a surface of an image bearing member by applying a voltage to the conductive-magnetic-particle carrying member and causing the conductive magnetic particles to contact the image bearing member, (ii) a latent-image forming step of forming an electrostatic latent image on the charged surface of the image bearing member, and (iii) a developing step of using a developing device facing the image bearing member and including a two-component developer including a toner and magnetic carrier particles, a developer carrying member for carrying the two-component developer, and a plurality of magnetic-field generation means provided within the developer carr
    Type: Grant
    Filed: March 13, 2000
    Date of Patent: September 25, 2001
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yoshiaki Kobayashi, Masaru Hibino, Masanori Shida, Ichiro Ozawa
  • Patent number: 6270933
    Abstract: The invention relates to a commercially useful color thermal transfer dye sublimation toner comprising at least a binder resin and a sublimation dye component, the binder resin comprising a high molecular weight polymer having a molecular weight of above about 75,000, and a temperature, T1, of at least about 160° C. at which the viscosity is equal to 1×103, and the sublimation dye comprising a dye which sublimes at elevated temperatures above about 100° C. The invention further defines a process for the use of the toner.
    Type: Grant
    Filed: June 29, 2000
    Date of Patent: August 7, 2001
    Assignee: International Communication Materials, Inc.
    Inventor: Richard J. Thompson
  • Patent number: 6248491
    Abstract: The present invention provides a polyester resin toner which has good fixing properties and is superior in image quality in a heat roller fixation system without employing an anti-offset solution, and which has a spherical or generally spherical shape and has a small particle diameter, and a method of producing the same. In a toner for electrostatic image development comprising a binder resin and a colorant, said binder resin is made of a polyester resin. Furthermore, the weight-average molecular weight as measured by gel permeation chromatography of a tetrahydrofuran-soluble fraction of said polyester resin contained in the toner is 30,000 or more and the weight-average molecular weight/number-average molecular weight is 12 or more and, moreover, the area ratio of a molecular weight of 600,000 or more is 0.5% or more and the area ratio of a molecular weight of 10,000 or less is within a range of 20-80%.
    Type: Grant
    Filed: September 21, 2000
    Date of Patent: June 19, 2001
    Assignee: Dainippon Ink and Chemical Inc.
    Inventors: Hitoshi Takayanagi, Minoru Nomura, Takashi Ito, Kenichi Hirabayashi, Yukiko Soma, Toshiro Kogawara, Toyomi Hashizume, Kazuo Itoya
  • Patent number: 6242148
    Abstract: The present invention uses a toner containing a styrene-acrylic resin having a glass transition point between 50 and 65° C. and a 150° C. melt index between 1 and 10 (g/10 min.), a polyethylene wax in 1 to 3% by weight. of the total weight of the toner, which wax has a melting point between 90 and 128° C., and a polypropylene wax in 3 to 6% by weight. of the total weight of the toner, which wax has a melting point between 135 and 146° C.
    Type: Grant
    Filed: February 23, 2000
    Date of Patent: June 5, 2001
    Assignee: Toshiba Tec Kabushiki Kaisha
    Inventor: Takahiro Nakajima
  • Patent number: 6232030
    Abstract: The present invention relates to a process for manufacturing a toner comprising the step of melt-kneading a composition comprising a resin binder and a colorant using an open roller-type continuous kneader having heating and cooling functions. According to the process for manufacturing a toner, there can be manufactured a toner which is excellent in the dispersion of the colorant and/or wax, and a toner having controlled dispersibilities of the charge control agent and the wax.
    Type: Grant
    Filed: May 1, 2000
    Date of Patent: May 15, 2001
    Assignee: Kao Corporation
    Inventors: Yasuhisa Otani, Toshihiro Hattori
  • Patent number: 6232025
    Abstract: A photoconductor comprises a substrate and at least one layer. The at least one layer is selected from the group consisting of charge transfer layers comprising a charge transfer molecule, polycarbonate and a first polyaryl ether selected from the group consisting of polyaryletherketones, poly(aryl-perfluoroaryl ether)s, polyaryletherketone-hydrazones, polyaryletherketone-azines and mixtures and copolymers thereof; charge generating layers comprising a pigment, a polyvinylbutyral and a second polyaryl ether selected from the group consisting of polyaryletherketones, polyarylethersulfones and mixtures and copolymers thereof, and mixtures thereof.
    Type: Grant
    Filed: January 10, 2000
    Date of Patent: May 15, 2001
    Assignee: Lexmark International, Inc.
    Inventor: Kasturi R. Srinivasan
  • Patent number: 6225016
    Abstract: A photoconductor for electrophotography includes a photosensitive film containing a bisazo charge generation agent described by structural formula (I) and from 100 nmol to 40 mmol, preferably from 500 nmol to 20 mmol, of a compound described by a structural formula (II) with respect to 1 mol of the bisazo charge generation agent. Such a photoconductor for electrophotography minimizes visual defects and image nonuniformity.
    Type: Grant
    Filed: August 25, 2000
    Date of Patent: May 1, 2001
    Assignee: Fuji Electric Imaging Device Co., Ltd.
    Inventors: Teruo Sasaki, Yoichi Nakamura
  • Patent number: 6225015
    Abstract: Oxytitanium phthalocyanine having a novel crystal form having excellent electrophotographic properties, such as a high charge potential, a high sensitivity and stable performances free from causing changes in various properties in repeated use, can be produced in the absence of a halogen substance, by carrying out the crystal transformation of amorphous oxytitanium phthalocyanine in a solvent comprising water and naphthalene.
    Type: Grant
    Filed: June 3, 1999
    Date of Patent: May 1, 2001
    Assignee: Mitsubishi Paper Mills Ltd.
    Inventors: Makoto Okaji, Michihiko Sato, Kazuyuki Suruga, Tamotsu Horiuchi
  • Patent number: 6221547
    Abstract: The invention relates to a photosensitive drum based on a cylindrical base which is made with an electrically conductive resin composition which comprises a polyamide resin as the resin component and an electrically conductive material, said polyamide resin being one selected from the group consisting of polyamide resins obtained from m-xylylenediamine and adipic acid, polyamide resins obtained from &egr;-caprolactam, and mixtures thereof. The cylindrical base for the photosensitive drum has good surface smoothness as well as good mechanical strength, and it can be obtained easily by injection molding or the like from said resin composition.
    Type: Grant
    Filed: August 30, 1999
    Date of Patent: April 24, 2001
    Assignee: Bridgestone Corporation
    Inventors: Munenori Iizuka, Youichi Nishimuro, Kunio Machida
  • Patent number: 6218064
    Abstract: In an electrophotographic apparatus having a structure for scrape-cleaning a developer of an average particle diameter of 5 to 8 &mgr;m with an elastic rubber blade having a modulus of repulsion elasticity of not less than 10% nor more than 50%, by using a light receiving member having a surface layer comprised of a non-monocrystalline fluorinated carbon film in which the wear loss after copying steps of 10,000 A4-size transfer sheets is not less than 0.1 Å nor more than 100 Å, in which the dynamic hardness is within the range of 10 to 500 kgf/mm2, and in which the fluorine content is not less than 5 atomic % nor more than 50 atomic %, an electrophotographic apparatus is provided which can prevent scattering or fusion of a developer, uneven scraping of a surface layer and image smearing irrespective of the service environment conditions and also can prevent image smearing without provision of means for directly heating the light receiving member.
    Type: Grant
    Filed: November 24, 1999
    Date of Patent: April 17, 2001
    Assignee: Canon Kabushiki Kaisha
    Inventors: Shigenori Ueda, Junichiro Hashizume, Ryuji Okamura
  • Patent number: 6214510
    Abstract: An external addition toner that sufficiently exhibits the effect of an external additive and is excellent in transfer property, and an apparatus for forming an image and a process for forming an image excellent in general purpose property that provide an image of good quality without formation of image defects, such as transfer unevenness and drop off due to transfer failure of the toner. An external addition toner is employed, in which the shape coefficient of the toner particles, as well as a coating ratio x (%) of the external additive to a surface area of the toner particles, a volume average particle diameter D (&mgr;m) of the toner particles and a volume average particle diameter d (&mgr;m) of the external additive having the maximum average particle diameter satisfy the prescribed relationship.
    Type: Grant
    Filed: August 25, 2000
    Date of Patent: April 10, 2001
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Noriaki Kojima, Hiroyuki Koide, Kazuhisa Masuko, Takatoshi Ishikawa
  • Patent number: 6214505
    Abstract: A photoconductive imaging member containing a photogenerating layer and a charge transport layer, and wherein the charge transport layer contains a poly(imide-carbonate) resin binder of (I) or (II) wherein A, B and E are divalent linkages; D is a trivalent linkage in (I) and a tetravalent linkage in (II); and x and y represent mole fractions wherein the sum of x+y is equal to 1.
    Type: Grant
    Filed: July 18, 2000
    Date of Patent: April 10, 2001
    Assignee: Xerox Corporation
    Inventors: Beng S. Ong, Yu Qi, Cheng-Kuo Hsiao
  • Patent number: 6214503
    Abstract: The invention features organic photoreceptors that include a charge transport compound having the formula: where X is an N-alkyl-substituted carbazole, an N-aryl-substituted carbazole, or a p-(N,N-disubstituted)arylamine; Ar is a group having the formula: R1 is a hydrogen, halogen, or alkyl group; R is a hydrogen, halogen, OH, CN, OR2, or OCOR3 group; R2 is an alkyl, aryl, or alkaryl group; R3 is a hydrogen, alkyl, aryl, or haloalkyl group; n is 0 or 1; A is a group having the formula: Z is O or S; Q is O, S, or CH2; and m is 0 or 1.
    Type: Grant
    Filed: December 21, 1999
    Date of Patent: April 10, 2001
    Assignee: Imation Corp.
    Inventors: Valentas Gaidelis, Janina Gavutiene, Vytautas Getautis, Juozas Vidas Grazulevicius, Vygintas Jankauskas, Rimtautas Kavaliunas, Ruta Lazauskaite, Osvaldas Paliulis, Mitchell A. Rossman, Donatas Jonas Sidaravicius, Terrance P. Smith, Albina Stanishauskaite
  • Patent number: 6214506
    Abstract: An electrophotographic photosensitive member, including: a conductive substrate; an undercoat layer formed on the conductive substrate, which contains a binder resin and metal oxide particles treated with an organic metal compound represented by formula (1): where M is —Si3, —TiR3 or Al; R is a hydrogen atom or a C1 to C6 alkyl group; R1 and R2 are each, independently, a C1 to C6 alkyl group; R3 is a C1 to C6 alkyl group which may be substituted with an alkoxy group or a C1 to C6 alkoxy group which may be substituted with an alkoxy group; and a photosensitive layer formed on the undercoat layer.
    Type: Grant
    Filed: July 28, 1999
    Date of Patent: April 10, 2001
    Assignee: Mitsubishi Chemical Corporation
    Inventors: Syunichiro Kurihara, Takahiro Choda
  • Patent number: 6214502
    Abstract: Charge generation layers comprise a charge generation compound and a binder which comprises polyvinylbutyral and phenolic resol. Dual layer photoconductors comprise the charge generation layer in combination with a substrate and a charge transport layer, in which the charge generation layer comprises a charge generation compound and a binder which comprises polyvinylbutyral and phenolic resol. Dual layer photoconductors comprise the charge generation layer in combination with a substrate and a charge transport layer, in which the charge generation layer comprises a charge generation compound and a binder which comprises polyvinylbutyral and a resin selected from the group consisting of phenol novolac and polyhydroxystyrene.
    Type: Grant
    Filed: March 28, 2000
    Date of Patent: April 10, 2001
    Assignee: Lexmark International, Inc.
    Inventors: Kasturei Rangan Srinivasan, Ronald Harold Levin, Garry D. Hinch, Gregory Walter Haggquist
  • Patent number: 6210848
    Abstract: An electrophotographic photoconductor has an electroconductive support and a photoconductive layer formed thereon, a surface top portion of the photoconductor containing a high-molecular charge transport material including a polycarbonate copolymer synthesized from (a) a bisphenol monomer with an ionization potential of 6.0 eV or less, having a positive hole transporting function, and (b) a bisphenol monomer having a substituent at the o-position with respect to at least one hydroxyl group thereof, the substituent being bulkier than a fluorine atom. A process cartridge holds the above-mentioned photoconductor therein, and an electrophotographic image forming apparatus is provided with the above-mentioned photoconductor or process cartridge.
    Type: Grant
    Filed: April 28, 2000
    Date of Patent: April 3, 2001
    Assignee: Ricoh Company, Ltd.
    Inventors: Kazukiyo Nagai, Tetsuro Suzuki, Masaomi Sasaki, Kohkoku Ri, Shinichi Kawamura