Patents Examined by Roland Martin
  • Patent number: 6143456
    Abstract: A carrier core for use in an electrostatographic developer composition is a ferrite substantially free of copper and zinc. By being substantially free of copper and zinc, the carrier core is environmentally friendly and eliminates the need for use of conventional copper zinc carrier cores which must be handled as hazardous waste. Developer compositions employing the ferrite carrier core possess suitable properties.
    Type: Grant
    Filed: November 24, 1999
    Date of Patent: November 7, 2000
    Assignee: Xerox Corporation
    Inventors: Scott M. Silence, George R. Hsu, Brian E. Moore, Morris M. Deyoung, Jr.
  • Patent number: 6144825
    Abstract: An image forming apparatus using an electrophotographic processor with a transfer roller, a charge roller and a photosensitive drum for image formation. The photosensitive drum is comprised of a cylindrical elastic body exhibiting a predetermined level of elasticity; a conductive film formed on an outer surface of said cylindrical elastic body; an image carrier generation layer of a first photoconductive material formed on the conductive film; and an image carrier transfer layer of a second photoconductive material formed on said image carrier generation layer.
    Type: Grant
    Filed: April 7, 1998
    Date of Patent: November 7, 2000
    Assignee: SamSung Electronics Co., Ltd.
    Inventor: Ki-Ju Park
  • Patent number: 6140000
    Abstract: A toner for electrophotography comprises a resin, a colorant and a charge controlling agent, wherein the charge controlling agent is substantially present on a surface part of the toner, and wherein the toner has a saturated charge quantity (absolute value) of from about 10-40 .mu.C/g when the toner is mixed with a carrier which is coated with a silicone resin, and a carrier contamination degree not greater then about 20%.
    Type: Grant
    Filed: October 7, 1998
    Date of Patent: October 31, 2000
    Assignee: Ricoh Company, Ltd.
    Inventor: Hiroshi Yamashita
  • Patent number: 6140004
    Abstract: An organic photoreceptor that includes:(a) a charge transport compound having the formula ##STR1## where n is an integer between 2 and 6, inclusive; R.sup.1 and R.sup.2, independently, are an alkyl group, a cycloalkyl group, or an aryl group, or R.sup.1 and R.sup.2 combine with the nitrogen atom to form a ring;Y is a bond, a carbon atom, a --CR.sup.3 group, an aryl group, a cycloalkyl group, or a cyclosiloxyl group;R.sup.3 is hydrogen, an alkyl group, or an aryl group; andX is a linking group having the formula --(CH.sub.2).sub.m -- wherein m is an integer between 4 and 10, inclusive, and one or more of the methylene groups is optionally replaced by an oxygen atom, a carbonyl group, or an ester group;(b) a charge generating compound; and(c) an electroconductive substrate.
    Type: Grant
    Filed: December 16, 1999
    Date of Patent: October 31, 2000
    Assignee: Imation Corp.
    Inventors: Andrew W. Mott, David J. Owen, Nusrallah Jubran, Martin D. Attwood, Richard A. Barcock, Richard J. Ellis, Rachel J. Hobson, David R. McGill
  • Patent number: 6136488
    Abstract: A flash fixing toner comprising a binding resin, a coloring agent, and an infrared absorbent, the infrared absorbent having the largest absorption wavelength in the range of 750-1100 nm, and the infrared absorbent being solved in or being finely dispersed in the binding resin.
    Type: Grant
    Filed: July 16, 1998
    Date of Patent: October 24, 2000
    Assignee: Nippon Shokubai Co., Ltd.
    Inventors: Mitsuo Kushino, Osamu Kaieda, Tatsuhito Matsuda, Makoto Matsumoto
  • Patent number: 6136491
    Abstract: Titanium oxide, silica having a BET specific surface area of 10 to 50 m.sup.2 /g, and metal soap having a volume average grain diameter of 1 to 5 .mu.m are added to toner particles. With such toner, it becomes possible to stabilize the charge amount and suppress the spent toner, filming and scratches on the photoreceptor, and therefore an image with an excellent reproducibility of half tone, can be obtained at high fineness degree in a later stage in its life.
    Type: Grant
    Filed: March 16, 2000
    Date of Patent: October 24, 2000
    Assignee: Toshiba TEC Kabushiki Kaisha
    Inventor: Toshiaki Yamauchi
  • Patent number: 6132921
    Abstract: An electrostatic-charged image developing toner containing a binder resin and a coloring agent, which is excellent in the fixing characteristics, has high charging uniformity and stability, and gives excellent images, wherein the crosslinking molecular weight Mc of the toner obtained by a temperature dispersion measurement in the dynamic viscoelasticity of the toner is from about 1.6.times.10.sup.4 to 3.5.times.10.sup.6, or the crosslinking density Me thereof is from about 1.6.times.10.sup.-8 to 3.5.times.10.sup.-6 /Kmol.
    Type: Grant
    Filed: February 29, 2000
    Date of Patent: October 17, 2000
    Assignee: Fuji Xerox Co., Ltd
    Inventors: Takao Ishiyama, Manabu Serizawa, Takeshi Shoji, Yukiko Watanabe, Yasuo Matsumura
  • Patent number: 6132917
    Abstract: A carrier comprised of a core and thereover a polymer generated from a blend of a polymer containing amine groups and a second polymer containing carboxylic acid functional groups.
    Type: Grant
    Filed: March 29, 2000
    Date of Patent: October 17, 2000
    Assignee: Xerox Corporation
    Inventors: Thomas R. Hoffend, Robert D. Bayley, Carol A. Fox, John G. VanDusen, Scott M. Silence, K. Derek Henderson
  • Patent number: 6132911
    Abstract: A method of manufacturing an organic pigment including the steps of providing an organic pigment wet cake which includes at least an organic pigment and a solvent and drying the organic pigment wet cake while the wet cake is heated at a temperature higher than room temperature to prepare a powder of the organic pigment, wherein the organic pigment is present in the organic pigment wet cake in an amount of not greater than about 70% by weight.
    Type: Grant
    Filed: July 22, 1999
    Date of Patent: October 17, 2000
    Assignee: Ricoh Company, Ltd.
    Inventor: Tatsuya Niimi
  • Patent number: 6132915
    Abstract: Provided is an image-forming process including a step of forming an electrostatic latent image on a latent image-carrier and a step of developing the latent image by a developer on a developer-carrier disposed facing the electrostatic latent image-carrier, a developer contains a color toner containing a wax which amount is from 1 to 10% by weight of the toner is used, and the developer-carrier wherein a ten-point average roughness (Rz) of the surface thereof of and the average spacing (Sm) of roughness peaks meet the following formula is used; 5.ltoreq.Rz.times.20.ltoreq.Sm. By the process, the conveying property of the developer is good, staining of the surface of the developer-carrier can be prevented, and images having a high quality and excellent in the fixing property over a long period time is obtained even in the case of using oil-less color toners containing a wax.
    Type: Grant
    Filed: November 30, 1999
    Date of Patent: October 17, 2000
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Susumu Yoshino, Yasuhiro Oya, Masanobu Ninomiya, Hirokazu Hamano, Koutarou Yoshihara, Kaori Oishi, Tetsuya Taguchi, Haruhide Ishida
  • Patent number: 6132919
    Abstract: A polymerized toner of core-shell structure, comprising core particles composed of colored polymer particles, which comprise a polyfunctional ester compound formed of a trifunctional or still higher polyfunctional polyhydric alcohol and a carboxylic acid, and a colorant, and shell which is formed of a polymer having a glass transition temperature higher than that of a polymer component making up the core particles and covers each of the core particles, a production process thereof, an image forming process comprising using the polymerized toner, and an image forming apparatus containing the polymerized toner.
    Type: Grant
    Filed: May 5, 1999
    Date of Patent: October 17, 2000
    Assignee: Nippon Zeon Co., Ltd.
    Inventors: Tokudai Ogawa, Noboru Yanagida, Takahiro Takasaki, Kazuhiro Sato
  • Patent number: 6132914
    Abstract: An electrophotographic photoconductor has an electroconductive support, and a photoconductive layer formed thereon which contains at least one bisazo compound of formula (I): ##STR1## wherein Cp.sup.1 and Cp.sup.2 are each a coupler radical which may be the same or different. Further, these are disclosed a bisazo compound of formula (II), and raw materials thereof, that is, 1,4-bis[4-(4-nitrophenyl)-1,3-butadienyl]benzene of formula (V), 1,4-bis[4-(4-aminophenyl)-1,3-butadienyl]benzene of formula (VI) and a bis(diazonium salt) compound of formula (III).
    Type: Grant
    Filed: April 7, 1999
    Date of Patent: October 17, 2000
    Assignee: Ricoh Company, Ltd.
    Inventor: Tomoyuki Shimada
  • Patent number: 6132920
    Abstract: The present invention relates to a toner comprising:toner particles containing a binder resin and a colorant; andan external addition agent that is admixed with the toner particles,the external addition agent comprising titanium oxide particles which are produced through a vapor-phase oxidizing method and has a number-average particle size of 0.1 to 0.7 .mu.m.
    Type: Grant
    Filed: November 8, 1999
    Date of Patent: October 17, 2000
    Assignee: Minolta Co., Ltd.
    Inventors: Masayuki Hagi, Junichi Tamaoki, Takeshi Arai, Megumi Aoki
  • Patent number: 6130020
    Abstract: The present invention relates to a developing agent comprising:toner particles containing at least a binder resin and a coloring agent; andmetallic oxide fine particles represented by a composition formula Si.sub.x A.sub.y O .sub.4x+yz)/2 (wherein the character A represents a metallic element, the character Z represents a valence number of element A, and x/y is 1-25), the metallic oxide fine particles being hydrophobically treated if desired.
    Type: Grant
    Filed: December 9, 1998
    Date of Patent: October 10, 2000
    Assignee: Minolta Co., Ltd.
    Inventors: Minoru Wada, Junji Machida, Osamu Ebisu
  • Patent number: 6130018
    Abstract: A carrier for use in development of an electrostatic latent image and an image forming apparatus using the carrier, with which a stable charging ability is maintained for a long period of time, and a high density image free from fog can be formed. The carrier has magnetic material particles coated with a coating resin. The coating resin is a thermoplastic resin, with a hardness of rank F to B in the terms of the pencil scratch test, and is present in an amount of 0.5 to 5 parts by weight to 100 parts by weight of the magnetic material particles.
    Type: Grant
    Filed: July 27, 1999
    Date of Patent: October 10, 2000
    Assignee: Kyocera Mita Corporation
    Inventors: Hideaki Kawata, Akinori Koyama, Nobuaki Kawano
  • Patent number: 6127083
    Abstract: A non-magnetic one-component development process is provided which comprises supplying a developer onto a photoreceptor using a non-magnetic one-component developing machine comprising at least a developer-supporting roll and a layer-forming blade so that an electrostatic latent image on said photoreceptor is developed, characterized in that as said developer there is used a spherically particulate toner having a volume-average particle diameter of from 1 to 6 .mu.m and the amount of said toner to be attached to said developer-supporting roll is from 0.1 mg/cm.sup.2 to 0.45 mg/cm.sup.2. In accordance with the process of the present invention, the image quality can be drastically improved while drastically reducing the consumed amount of the toner.
    Type: Grant
    Filed: January 29, 1999
    Date of Patent: October 3, 2000
    Assignee: Dainippon Ink and Chemicals, Inc.
    Inventors: Minoru Nomura, Takashi Ito, Hitoshi Takayanagi, Kazuo Itoya
  • Patent number: 6127081
    Abstract: Disclosed is a developing agent which permits preventing occurrence of offset and spent toner, which permits obtaining a picture image having a sufficiently high image density, which can be used in a fixing device that does not include an oil supply mechanism. The developing agent comprises a coloring agent, a binder containing a polyester resin as a main component, a charge controller consisting of a zirconium complex compound of a salicylic acid derivative, silica subjected to a hydrophobic treatment, and titanium oxide.
    Type: Grant
    Filed: November 18, 1999
    Date of Patent: October 3, 2000
    Assignees: Toshiba Tec Kabushiki Kaisha, Kabushiki Kaisha Toshiba
    Inventor: Toshiaki Yamauchi
  • Patent number: 6127079
    Abstract: A two-component-type developing agent comprising a silicone resin-coated carrier and a positively charging toner, the silicone coated carrier having an average particle diameter of from 60 to 110 .mu.m, the silicone resin coating having an average thickness of from 0.1 to 0.3 .mu.m, the carrier having a resistivity of from 1.5.times.10.sup.8 to 1.5.times.10.sup.11 .OMEGA..multidot.cm, the toner concentration being from 3.0 to 5.0 % by weight and the amount of electric charge by friction of the toner based on the suction method being from +10 to +20 .mu.c/g.
    Type: Grant
    Filed: December 16, 1999
    Date of Patent: October 3, 2000
    Assignee: Kyocera Mita Corporation
    Inventors: Tadao Sumiyoshi, Tomohide Iida
  • Patent number: 6127078
    Abstract: An organic electrophotographic photoconductor diminished in an image trouble due to history of a transfer process in a reversal development system is disclosed. The above organic electrophotographic photoconductor is called a separated-function laminated type organic electrophotographic photoconductor, which has an undercoat layer and a photosensitive layer laminated in this order on a conductive substrate, the photosensitive layer comprising a charge generation layer laminated on the undercoat layer and containing an organic compound, and a charge transport layer laminated on the charge generation layer and containing an organic compound. For the charge generation layer, a titanyloxyphthalocyanine compound is used as a charge generation material. The present invention uses the titanyloxyphthalocyanine compound having a clear diffraction peak at a Bragg angle (2.theta.) of 9.6.degree..+-.0.2.degree. or 27.3.degree..+-.0.2.degree. for CuK.alpha. characteristic X-ray (wavelength 1.541 .ANG.).
    Type: Grant
    Filed: January 4, 2000
    Date of Patent: October 3, 2000
    Assignee: Fuji Electric Co., Ltd.
    Inventors: Shinichi Omokawa, Kenichi Ohkura, Seishi Terasaki, Yoshihiro Ueno, Kenji Kawate
  • Patent number: 6127076
    Abstract: Naphthalenetetracarboxylic acid diimide derivatives represented by the following general formula, ##STR1## wherein R is a hydrogen atom, an alkyl group, an alkoxyl group or a halogen atom, R1 and R2 are different from each other and may be a substituted or unsubstituted alkyl group, alkoxyl group or an aryl group, respectively, and R3 is a hydrogen atom, a substituted or unsubstituted alkyl group, an alkoxyl group or an aryl group.The derivatives exhibit excellent solubility in an organic solvent, excellent compatibility with a resin binder and excellent photosensitivity, and are very useful as an electron transporting agent for the electrophotosensitive material.
    Type: Grant
    Filed: May 27, 1999
    Date of Patent: October 3, 2000
    Assignee: Kyocera Mita Corporation
    Inventors: Kou Ishigami, Fumio Sugai, Yasufumi Mizuta