Patents by Inventor Osamu Uchinokura

Osamu Uchinokura has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 7318989
    Abstract: To provide a toner that can provide long-term removability and high-definition images with reduced image layer thickness and densely-packed toner particles, a developer capable of forming high-quality images using the toner, a toner container for containing the toner, a process cartridge using the toner, an image forming apparatus using the toner, and an image forming method using the toner. The toner of the present invention is a toner having a substantially spherical shape with irregularities on its surface and containing at least a binder resin and a colorant, wherein a surface factor SF-1 that represents the sphericity of toner particles is 105 to 180, a surface factor SF-2 that represents the degree of surface irregularities of the toner particles is correlated with the volume-average diameter of the toner particles, and the toner particles have an inorganic oxide particle-containing layer within 1 ?m from their surfaces.
    Type: Grant
    Filed: August 3, 2006
    Date of Patent: January 15, 2008
    Assignee: Ricoh Company, Ltd.
    Inventors: Akihiro Kotsugai, Satoshi Mochizuki, Hisashi Nakajima, Yasuo Asahina, Osamu Uchinokura, Masayuki Ishii, Tomoyuki Ichikawa, Shinya Nakayama, Koichi Sakata, Tomoko Utsumi, Hitoshi Iwatsuki, Yasuaki Iwamoto, Hideki Sugiura, Masami Tomita
  • Patent number: 7300736
    Abstract: A toner contains: (A) a binder resin; (B) a colorant; (C) a charge controlling agent; and (D) an additive. (A) contains: a polyester resin containing no tetrahydrofuran-insoluble component; and having components having a molecular weight not greater than 5×102 present in an amount of 4% or less by weight, a main peak present in a molecular weight range of from 3×103 to 9×103 as determined by gel permeation chromatography. (C) contains: a metal salt of salicylic acid or salicylic acid derivative. (D) contains: a hydrophobized silica having a primary particle diameter of from 0.01 to 0.03 ?m; and a hydrophobized titanium oxide having a primary particle diameter of from 0.01 to 0.03 ?m, a specific surface area of from 60 to 140 m2/g, one or more water-soluble components in an amount of 0.2% or more by weight, a transmittance not less than 35% for light having a wavelength of 300 nm and a transmittance not less than 80% for light having a wavelength of 600 nm.
    Type: Grant
    Filed: May 27, 2004
    Date of Patent: November 27, 2007
    Assignee: Ricoh Company, Ltd.
    Inventors: Hiroyuki Fushimi, Osamu Uchinokura
  • Publication number: 20070264035
    Abstract: A toner is provided that contains: (A) a binder resin; (B) a colorant; (C) a charge controlling agent; and (D) an additive; wherein the binder resin (A) contains: a polyester resin containing no tetrahydrofuran-insoluble component; and having a molecular weight distribution wherein components having a molecular weight not greater than 5×102 are present in an amount of 4% or less by weight, and wherein a main peak is present in a molecular weight range of from 3×103 to 9×103 when the molecular weight distribution is determined by gel permeation chromatography; wherein the charge controlling agent (C) contains: a metal salt of salicylic acid or salicylic acid derivative; and wherein the additive (D) contains: a hydrophobized silica having a primary particle diameter of from 0.01 to 0.03 ?m; and a hydrophobized titanium oxide having a primary particle diameter of from 0.01 to 0.
    Type: Application
    Filed: July 24, 2007
    Publication date: November 15, 2007
    Inventors: Hiroyuki Fushimi, Osamu Uchinokura
  • Publication number: 20070218389
    Abstract: A toner is provided including a colorant; a binder resin (A) which is a polyester resin having no tetrahydrofuran insoluble component, and having a molecular weight distribution such that components having a molecular weight of not greater than 500 are included in an amount of not greater than 4% by weight and a peak is present in a molecular weight range of from 3,000 to 9,000 when measured by gel permeation chromatography (GPC); and a binder resin (B) which is a polyester resin having no tetrahydrofuran insoluble component, and including units of a polycarboxylic acid and a diol having the specific formula; wherein at least one of the binder resins (A) and (B) is prepared in the presence of the specific titanium-containing catalyst, and wherein a weight ratio ((A)/(B)) of the binder resin (A) to the binder resin (B) is from 60/40 to 85/15.
    Type: Application
    Filed: March 14, 2007
    Publication date: September 20, 2007
    Inventors: Takahiro Honda, Hiroyuki Fushimi, Osamu Uchinokura
  • Publication number: 20070218380
    Abstract: A toner containing a colorant, a binder resin and a laminar inorganic mineral in which part or all of the ions present between layers are modified by organic ions. The toner can be prepared by a method including dispersing or emulsifying a toner constituent mixture liquid containing the colorant, the binder resin and/or a precursor thereof, and the laminar inorganic mineral, in an aqueous medium. The density of the laminar inorganic mineral measured by XPS for the toner surface before (A) and after(B) mixing and kneading satisfies the following relationship: A>B.
    Type: Application
    Filed: March 14, 2007
    Publication date: September 20, 2007
    Inventors: Osamu UCHINOKURA, Naohiro Watanabe, Junichi Awamura
  • Publication number: 20070218381
    Abstract: It is an object to provide toner excellent in charge stability, fixing property at low temperature, durability, microdot reproducibility and cleaning ability. An excellent image forming apparatus using the toner is provided. Said toner has at least a plurality of resins, a colorant and a layered inorganic material in which at least a part of ions in the layered inorganic material has been exchanged with organic ions in the toner prepared by dispersing and/or emulsifying an oil phase comprising at least a toner composition and/or a toner composition precursor in a water-based medium to granulate, and wherein a first resin in said a plurality of resins has a weight average molecular weight of 3,000 to 10,000 in a molecular weight distribution obtained by gel permeation chromatography (GPC).
    Type: Application
    Filed: March 14, 2007
    Publication date: September 20, 2007
    Inventors: Osamu Uchinokura, Naohiro Watanabe, Junichi Awamura
  • Patent number: 7258959
    Abstract: The object of the present invention is to provide a developer having a sharp charge amount distribution and bringing out high-quality image without substantially smearing a charging unit, developing units, a photoconductor, and an intermediate transferring member by the developer, namely, a developer capable of providing an appropriate image density and exhibiting extremely little background smear even when used over a long period of time and repeatedly used for a number of sheets of paper as well as to provide an image forming apparatus for electrophotography using the developer.
    Type: Grant
    Filed: September 26, 2005
    Date of Patent: August 21, 2007
    Assignee: Ricoh Company, Ltd.
    Inventors: Shinya Nakayama, Satoshi Mochizuki, Yasuaki Iwamoto, Yasuo Asahina, Kazuhiko Umemura, Hideki Sugiura, Hisashi Nakajima, Tomoyuki Ichikawa, Tomoko Utsumi, Koichi Sakata, Akihiro Kotsugai, Osamu Uchinokura, Masayuki Ishii
  • Publication number: 20070134581
    Abstract: The present invention provides a method for producing a toner including preparing an emulsified dispersion which contains emulsion particles by emulsifying or dispersing an oil phase containing at least a pigment and any one of a binder resin and a binder resin precursor in an aqueous medium, and granulating toner base particles by converging the emulsified dispersion, wherein the Casson yield value of the single oil phase before being emulsified or dispersed in the aqueous medium is 0.5 Pa to 20 Pa; and the temperature Tn of the emulsified dispersion in the preparation of the emulsified dispersion, the temperature Ts of the emulsified dispersion in the granulation of the toner base particles, and the glass transition temperature Tg of the toner base particles satisfy the relation Tn<Ts<Tg.
    Type: Application
    Filed: November 10, 2006
    Publication date: June 14, 2007
    Inventors: Osamu Uchinokura, Fumihiro Sasaki, Satoshi Mochizuki, Hidetoshi Noda, Tsuyoshi Fukushima, Koutaro Kitano
  • Publication number: 20070031748
    Abstract: To provide a toner that can provide long-term removability and high-definition images with reduced image layer thickness and densely-packed toner particles, a developer capable of forming high-quality images using the toner, a toner container for containing the toner, a process cartridge using the toner, an image forming apparatus using the toner, and an image forming method using the toner. The toner of the present invention is a toner having a substantially spherical shape with irregularities on its surface and containing at least a binder resin and a colorant, wherein a surface factor SF-1 that represents the sphericity of toner particles is 105 to 180, a surface factor SF-2 that represents the degree of surface irregularities of the toner particles is correlated with the volume-average diameter of the toner particles, and the toner particles have an inorganic oxide particle-containing layer within 1 ?m from their surfaces.
    Type: Application
    Filed: August 3, 2006
    Publication date: February 8, 2007
    Inventors: Akihiro Kotsugai, Satoshi Mochizuki, Hisashi Nakajima, Yasuo Asahina, Osamu Uchinokura, Masayuki Ishii, Tomoyuki Ichikawa, Shinya Nakayama, Koichi Sakata, Tomoko Utsumi, Hitoshi Iwatsuki, Yasuaki Iwamoto, Hideki Sugiura, Masami Tomita
  • Publication number: 20060204883
    Abstract: A toner which includes a toner material, wherein the toner satisfies the following formula: 0° C.??Tm?20° C. where ?Tm represents Tma (° C.)?Tmb (° C.), Tma (° C.) is ½ flown-out temperature of the toner by a capillary type flow tester, and Tmb (° C.) is ½ flown-out temperature of a melt kneaded mixture of the toner by the capillary type flow tester, and wherein Tma is from 130° C. to 200° C.
    Type: Application
    Filed: March 20, 2006
    Publication date: September 14, 2006
    Inventors: Shinya Nakayama, Satoshi Mochizuki, Yasuaki Iwamoto, Yasuo Asahina, Akihiro Kotsugai, Masayuki Ishii, Osamu Uchinokura, Hisashi Nakajima, Tomoyuki Ichikawa, Tomoko Utsumi, Koichi Sakata, Hideki Sugiura, Shigeru Emoto, Junichi Awamura, Masami Tomita, Takahiro Honda, Shinichiro Yagi, Tomomi Suzuki, Hiroshi Yamada, Toshiki Nanya, Hiroto Higuchi, Fumihiro Sasaki, Naohito Shimota
  • Publication number: 20060068313
    Abstract: The object of the present invention is to provide a developer having a sharp charge amount distribution and bringing out high-quality image without substantially smearing a charging unit, developing units, a photoconductor, and an intermediate transferring member by the developer, namely, a developer capable of providing an appropriate image density and exhibiting extremely little background smear even when used over a long period of time and repeatedly used for a number of sheets of paper as well as to provide an image forming apparatus for electrophotography using the developer.
    Type: Application
    Filed: September 26, 2005
    Publication date: March 30, 2006
    Inventors: Shinya Nakayama, Satoshi Mochizuki, Yasuaki Iwamoto, Yasuo Asahina, Kazuhiko Umemura, Hideki Sugiura, Hisashi Nakajima, Tomoyuki Ichikawa, Tomoko Utsumi, Koichi Sakata, Akihiro Kotsugai, Osamu Uchinokura, Masayuki Ishii
  • Publication number: 20060063081
    Abstract: It is an object of the present invention to provide a toner that can sustain favorable transferability and cleaning ability for prolonged periods; prevent photoconductor filming; exhibit no variation in image nonuniformity or external additive immersion induced by developer agitation at the time of use; excels in stability with flowability and charge stability over prolonged periods. Therefore, provided is the toner of which the quantity of aggregate of residual external additives found on the sieve of 635-mesh and 452 cm2 of mesh area, after 0.2 g of the toner on the sieve is blasted with air at a blow pressure of 0.2 MPa from 160 mm above the sieve while being air-suctioned at a suction force of 5 mmHg, and then air-suctioned at a suction force of 20 mmHg, is 4,500 or less and 5 or more.
    Type: Application
    Filed: September 16, 2005
    Publication date: March 23, 2006
    Inventors: Tsuneyasu Nagatomo, Akihiro Kotsugai, Hiroshi Yamashita, Masayuki Ishii, Hiroto Higuchi, Osamu Uchinokura, Satoshi Mochizuki, Fumihiro Sasaki, Hisashi Nakajima, Hideki Sugiura, Yasuo Asahina, Shinya Nakayama, Koichi Sakata, Tomoyuki Ichikawa, Takuya Saito, Sonoh Matsuoka
  • Publication number: 20060029433
    Abstract: A toner for an image forming apparatus having a volume average diameter of from 2 to 8 ?m is manufactured by reacting an aqueous dispersion comprising at least one pigment, a polymer and/or a mixture of monomers to form fine toner particles wherein the amount of fine particles having a diameter of one-half the average number diameter are present in an amount of 20% by number or less, a toner cartridge containing the toner and a method for using the toner.
    Type: Application
    Filed: July 29, 2005
    Publication date: February 9, 2006
    Inventors: Takuya Saito, Koichi Sakata, Tomoyuki Ichikawa, Shinya Nakaya, Hisashi Nakajima, Sonoh Matsuoka, Akihiro Kotsugai, Yasuo Asahina, Fumihiro Sasaki, Satoshi Mochizuki, Osamu Uchinokura
  • Publication number: 20050208408
    Abstract: A toner which is negatively charged to develop an electrostatic latent image is provided that contains a colorant; and a binder resin, wherein the toner has an acid value of from 5 to 20 mg KOH/g and an amine value of from 0.5 to 10 mg KOH/g.
    Type: Application
    Filed: March 16, 2005
    Publication date: September 22, 2005
    Inventors: Osamu Uchinokura, Masami Tomita, Hisashi Nakajima, Shinya Nakayama, Koichi Sakata, Akihiro Kotsugai, Tomoyuki Ichikawa, Yasuo Asahina, Hideki Sugiura, Yasuaki Iwamoto, Satoshi Mochizuki
  • Publication number: 20050208411
    Abstract: A toner containing toner particles having a core-shell structure containing a binder resin, a colorant and a release agent. The toner particles are prepared by dissolving or dispersing at least one of the binder resin and a precursor thereof in an organic solvent or a polymeric monomer and reacting the resultant in an aqueous medium for reaction, wherein the toner satisfies the following relationship: ?Tm=Tm1?Tm2>10 ° C., wherein Tm1 represents half efflux temperature of the toner and Tm2 represents half efflux temperature of a toner which is prepared by melting and kneading the toner particles and wherein a content of the release agent existing close to the surface portion of the toner particles is from 7 to 30% by volume based on an entire portion close to the surface portion of the toner particles when the content is determined by Fourier Transform Infrared Spectroscopy Attenuated Total Reflection (FTIR-ATR) method.
    Type: Application
    Filed: March 17, 2005
    Publication date: September 22, 2005
    Inventors: Shinya Nakayama, Fumihiro Sasaki, Satoshi Mochizuki, Akihiro Kotsugai, Yasuo Asahina, Osamu Uchinokura, Hisashi Nakajima, Sonoh Matsuoka, Takuya Saito, Tomoyuki Ichikawa, Koichi Sakata
  • Patent number: 6916587
    Abstract: A toner including at least a binder resin; a colorant; and a charge controlling agent, in which the binder resin includes at least a polyester resin having a molecular weight distribution such that components having a molecular weight not greater than 500 are included in an amount of 4% by weight and at least a peak is present in a range of from 3,000 to 9,000 when measured by Gel Permeation Chromatography. In addition, the binder resin does not include a tetrahydrofuran-insoluble compound and the charge controlling agent is a resin charge controlling agent including at least units obtained from a monomer including a sulfonate group; an aromatic monomer including an electron absorption group; and an acrylic ester and/or a methacrylic ester monomer.
    Type: Grant
    Filed: April 3, 2002
    Date of Patent: July 12, 2005
    Assignee: Ricoh Company Limited
    Inventors: Hiroyuki Fushimi, Toshiki Nanya, Osamu Uchinokura, Shinichiro Yagi, Kohki Katoh
  • Publication number: 20050089786
    Abstract: A toner including a binder resin; and a colorant, wherein a hexafluoroisopropanol (HFIP)-soluble component satisfies the following relationship: 2,000?Mn?7,000 and 1.5?Mn/Mw?10 wherein Mn represents a number-average molecular weight and Mw represents a weight-average molecular weight.
    Type: Application
    Filed: October 7, 2004
    Publication date: April 28, 2005
    Inventors: Hideki Sugiura, Satoshi Mochizuki, Akihiro Kotsugai, Yasuo Asahina, Osamu Uchinokura, Hisashi Nakajima, Tomoyuki Ichikawa, Shinya Nakayama, Kohichi Sakata, Tomoko Utsumi, Hitoshi Iwatsuki, Yasuaki Iwamoto
  • Publication number: 20050089787
    Abstract: An image forming method including: forming a toner image on a support using a toner including toner particles; and feeding the support bearing the toner image thereon through a nip between an endless toner heating member and a pressure roller to fix the toner image on the support, wherein the endless toner heating member is rotated while stretched by a fixing roller and a heat roller which includes a magnetic metal and which is heated by electromagnetic induction, and wherein the pressure roller presses the support to the endless toner heating member and the fixing roller at the nip, wherein the toner particles are prepared by a polymerizing method using a binder resin containing at least a modified polyester resin.
    Type: Application
    Filed: October 21, 2004
    Publication date: April 28, 2005
    Inventors: Osamu Uchinokura, Akihiro Kotsugai, Yasuo Asahina, Tomoyuki Ichikawa, Shinya Nakayama, Kohichi Sakata, Tomoko Utsumi, Hisashi Nakajima, Yasuaki Iwamoto, Hideki Sugiura, Satoshi Mochizuki
  • Patent number: 6855468
    Abstract: In a method for forming a multicolored toner image in accordance with an electrophotographic process, the addition amount of external additives to a non-added toner is 1.5 to 10.0 parts by weight per 100 parts by weight of the non-added toner in each developing step, the aggregation degree of the toner is within the range of 30 to 80%, and the change ratio of the aggregation degree satisfies the relation: 0.8?(initial aggregation degree/aggregation degree after no-load revolution of developing portion for 20 hours)?1.2. According to this method, it becomes possible to form a high-quality color image while a toner always keeps a stable degree of aggregation and a charge amount.
    Type: Grant
    Filed: November 16, 2000
    Date of Patent: February 15, 2005
    Assignees: Fujitsu Limited, Ricoh Company, Ltd.
    Inventors: Takashi Yamamoto, Masae Nakamura, Masakazu Kinoshita, Yoshimichi Katagiri, Shin-ichi Kuramoto, Hachiro Tosaka, Hiroshi Yamashita, Osamu Uchinokura
  • Publication number: 20050003289
    Abstract: A toner is provided that contains: (A) a binder resin; (B) a colorant; (C) a charge controlling agent; and (D) an additive; wherein the binder resin (A) contains: a polyester resin containing no tetrahydrofuran-insoluble component; and having a molecular weight distribution wherein components having a molecular weight not greater than 5×102 are present in an amount of 4% or less by weight, and wherein a main peak is present in a molecular weight range of from 3×103 to 9×103 when the molecular weight distribution is determined by gel permeation chromatography; wherein the charge controlling agent (C) contains: a metal salt of salicylic acid or salicylic acid derivative; and wherein the additive (D) contains: a hydrophobized silica having a primary particle diameter of from 0.01 to 0.03 ?m; and a hydrophobized titanium oxide having a primary particle diameter of from 0.01 to 0.
    Type: Application
    Filed: May 27, 2004
    Publication date: January 6, 2005
    Inventors: Hiroyuki Fushimi, Osamu Uchinokura