Patents by Inventor Mitsuo Aoki

Mitsuo Aoki 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).

  • Publication number: 20050079430
    Abstract: An image forming method, comprising passing a toner image-bearing sheet through a nip defined between two rollers including a heater roller to fix the toner image on the sheet, wherein the toner image is formed from a toner comprising a binder resin, and a colorant, wherein the toner image before the passage through the nip has a toner volume V1 and a toner image area S1, wherein the toner image after the passage through the nip has a toner volume V2 and a toner image area S2, and wherein a volume change Vt and an area change St defined by the formulas shown below are 30% or less and 20% or less, respectively: Vt(%)=(V1?V2)/V1×100 St(%)=(S2?S1)/S1×100. Alternatively, the toner image before the passage through the nip has a surface roughness of 2.5 ?m or less.
    Type: Application
    Filed: December 3, 2004
    Publication date: April 14, 2005
    Inventors: Mitsuo Aoki, Kumi Hasegawa, Toshiaki Higaya, Yasushi Koichi, Yutaka Takahashi, Tadashi Kasai
  • Publication number: 20050064310
    Abstract: A toner for forming a full color image, which includes a colorant and a binder resin including a polyester resin which is prepared by a polycondensation ester reaction in the presence of a titanium-containing catalyst selected from the group consisting of halogenated titanium, titanium diketone enolates, titanium carboxylates, titanyl carboxylates, and salts of titanyl carboxylates. A toner kit including a yellow toner, a magenta toner, a cyan toner and a black toner, wherein each of the toners is the toner mentioned above. An image forming apparatus including an image bearing member; a charger; a light irradiator; a developing device configured to develop an electrostatic latent image with a developer including the toner mentioned above; a transfer device; and a fixing device.
    Type: Application
    Filed: September 8, 2004
    Publication date: March 24, 2005
    Inventors: Minoru Masuda, Mitsuo Aoki, Kumi Hasegawa, Bing Shu
  • Publication number: 20050030595
    Abstract: In an image forming apparatus configured to electrostatically transfer a toner image formed on an image carrier to a recording medium with image transferring means of the present invention, pressure is applied between the image carrier and the image transferring means. Toner is provided with relatively high hardness in accordance with the pressure beforehand. Image transfer is effected by reducing a potential difference between the image carrier and the recording medium while maintaining an electric field around the toner the same.
    Type: Application
    Filed: August 29, 2003
    Publication date: February 10, 2005
    Inventors: Yasushi Koichi, Mitsuo Aoki, Bing Shu, Koji Suzuki, Shigeru Watanabe, Tadashi Kasai, Yutaka Takahashi
  • Publication number: 20050025535
    Abstract: In an image forming apparatus, a toner image is formed on a photosensitive element and a transfer roller, which carries a transfer medium, is pressed against a photosensitive element at a pressure of from 20.4 N/cm2 to 200 N/cm2.
    Type: Application
    Filed: June 30, 2004
    Publication date: February 3, 2005
    Inventors: Yasushi Koichi, Mitsuo Aoki, Bing Shu, Setsuo Soga, Koji Suzuki, Yutaka Takahashi, Tadashi Kasai
  • Publication number: 20040241566
    Abstract: An electrophotographic image forming apparatus capable of reliably forming an image with density gradation, one which does not have a low-quality appearance. The estimated average halftone granularity of the toner image after developing but before electrostatic transfer was set at 0.25 or less. The average halftone granularity was found by measuring the granularity of a toner image at locations of different average brightness by means of newly proposed formula, and averaging the measured values for which the average brightness is 40 to 80. The estimated average halftone granularity was obtained by estimating the average halftone granularity of the toner image on a photoreceptor by means of a newly proposed method.
    Type: Application
    Filed: March 23, 2004
    Publication date: December 2, 2004
    Inventors: Koji Suzuki, Mitsuo Aoki, Bing Shu, Yasushi Koichi, Setsuo Soga, Tadashi Kasai, Yutaka Takahashi
  • Publication number: 20040234879
    Abstract: A toner for electrophotography contains a binder resin, a charge control agent, and a colorant. The colorant is a black iron oxide compound containing 10 to 45% by weight of titanium component calculated in terms of Ti atom in relation to Fe atom when measured by wavelength dispersive X-ray fluorescence spectrometry. Peaks at Bragg angle 2&thgr; of the toner to Cu&kgr;&agr; X-ray are peak A at 32.9 degrees±0.3 degrees and peak B at 35.5 degrees±0.3 degrees, and X ray intensity ratio between peaks A and B (A/B) is in the range of 0.3 to 2.0 at a scan speed of 0.5 to 4 degrees/min.
    Type: Application
    Filed: March 16, 2004
    Publication date: November 25, 2004
    Inventors: Kumi Hasegawa, Mitsuo Aoki, Bing Shu, Toyoshi Sawada, Keiko Shiraishi, Masashi Nagayama, Shinichi Kuramoto
  • Publication number: 20040224247
    Abstract: An image formation method includes the steps of charging the surface of an electrophotographic photoconductor, exposing the charged photoconductor to a light image to form a latent electrostatic image on the photoconductor, developing the latent electrostatic image using a two-component developer containing a toner and a carrier to obtain a toner image, and transferring the toner image to an image receiving material directly or via an intermediate transfer member, with the photoconductor showing a surface friction coefficient of 0.40 or less, and the toner having toner particles with an average circularity of 0.930 or more.
    Type: Application
    Filed: June 21, 2004
    Publication date: November 11, 2004
    Inventors: Fumihiro Sasaki, Mitsuo Aoki, Yasuaki Iwamoto, Naohito Shimota, Kazuyuki Yazaki, Hiroaki Matsuda, Hiroshi Nakai, Kumi Hasegawa, Shinichiro Yagi, Hiroto Higuchi, Akemi Sugiyama
  • Publication number: 20040157147
    Abstract: A toner including a binder resin including a crystalline polyester and a non-crystalline resin; a release agent; and a black metal-containing material having a saturation magnetization not greater than 50 emu/g. A toner container containing the toner. A fixing method including passing a support with the toner image thereon through a nip between two cylindrical rollers while applying a pressure not greater than 1×105 Pa to the two cylindrical rollers, wherein one of the cylindrical rollers which contacts the toner image has a thickness not greater than 1.0 mm. An image forming method including developing an electrostatic image with the toner to form a toner image; transferring the toner image onto a receiving material; and fixing the toner image by the fixing method mentioned above. A process cartridge including an image bearing member and a developing device using the toner.
    Type: Application
    Filed: February 6, 2004
    Publication date: August 12, 2004
    Inventors: Keiko Shiraishi, Toyoshi Sawada, Masashi Nagayama, Shinichi Kuramoto, Mitsuo Aoki, Kumi Hasegawa, Bing Shu
  • Publication number: 20040146309
    Abstract: The image forming apparatus comprises a photoconductor, a latent electrostatic image forming unit for forming a latent electrostatic image on the photoconductor, a developing unit for developing the latent electrostatic image using a developer comprising a toner to form a visible image, a transfer unit for transferring the visible image to a recording medium, a cleaning unit for removing the developer remained on the photoconductor surface and a developer amount detection unit for detecting developer amount adhering to the photoconductor surface by a reflecting photosensor, wherein the developer stirring time per copy when one copy is made from an original, is 2 to 6 times the developer stirring time per copy when two or more copies are made from the original, wherein the toner comprises at least a binder resin and a wax, and the dynamic frictional coefficient of the toner is 0.15 to 0.45.
    Type: Application
    Filed: January 15, 2004
    Publication date: July 29, 2004
    Inventors: Bing Shu, Mitsuo Aoki, Haruji Mizuishi, Mikio Ishibashi, Masaru Tanaka, Shinji Tamaki, Hiroshi Mizusawa, Shin Hasegawa
  • Publication number: 20040076443
    Abstract: In a copier which is an image-forming apparatus comprising a photoconductor 1, a developing apparatus 4, transfer apparatus 5 which transfers a toner image formed on the photoconductor 1 to a transfer material by heat and pressure using a transfer roller 52, and a fixing apparatus which fixes the toner image transferred to the transfer material, on the transfer material, a heater 56, temperature detection apparatus 57 and temperature control apparatus are provided which controls the temperature to within a range of from the glass transition temperature (Tg) to the softening temperature (Tm) of the toner, and lower than the fixing temperature of the fixing apparatus 7.
    Type: Application
    Filed: August 1, 2003
    Publication date: April 22, 2004
    Inventors: Koji Suzuki, Mitsuo Aoki, Hiroto Higuchi, Shinya Nakayama, Maiko Kondo, Bing Shu, Yasushi Koichi, Tadashi Kasai, Yutaka Takahashi
  • Patent number: 6632939
    Abstract: The present invention relates to dextran whose boron content is reduced to a value less than 0.30 &mgr;g/g (dry basis) calculated on the basis of boron atom, a process for producing the same, and dextran with which a container is filled in a solution state. Dextran of the present invention is obtained by treating a boron-containing dextran with a lower alcohol, and said dextran has such a characteristic that deposition is inhibited or the deposition rate is drastically reduced when using it in the form of a solution. Therefore, an isotonic sodium chloride solution of said dextran is suitably used as substitute plasma or external perfusate in an operation.
    Type: Grant
    Filed: April 7, 2000
    Date of Patent: October 14, 2003
    Assignees: Meito Sangyo Co., Ltd., Otsuka Pharamaceutical Factory, Inc.
    Inventors: Haruo Machida, Shigeaki Kato, Yuuki Hirata, Mitsuo Aoki, Hideki Kobatake
  • Publication number: 20030186155
    Abstract: An image forming method, comprising passing a toner image-bearing sheet through a nip defined between two rollers including a heater roller to fix the toner image on the sheet, wherein the toner image is formed from a toner comprising a binder resin, and a colorant, wherein the toner image before the passage through the nip has a toner volume V1 and a toner image area S1, wherein the toner image after the passage through the nip has a toner volume V2 and a toner image area S2, and wherein a volume change Vt and an area change St defined by the formulas shown below are 30% or less and 20% or less, respectively:
    Type: Application
    Filed: September 23, 2002
    Publication date: October 2, 2003
    Inventors: Mitsuo Aoki, Kumi Hasegawa, Toshiaki Higaya, Yasushi Koichi, Yutaka Takahashi, Tadashi Kasai
  • Publication number: 20030165760
    Abstract: A toner for developing an electrostatic latent image, comprising a colorant, a releasing agent and a binder resin, wherein said binder resin comprises a first, non-linear resin, a second, linear resin, and a modified wax comprising a wax moiety and a vinyl polymer moiety having an ester group content of 8 to 30% by weight based on the weight of the vinyl polymer moiety.
    Type: Application
    Filed: December 27, 2002
    Publication date: September 4, 2003
    Inventors: Hiroto Higuchi, Mitsuo Aoki, Fumihiro Sasaki, Naohito Shimota, Kumi Hasegawa, Bing Shu, Maiko Kondo, Shinya Nakayama
  • Publication number: 20030104297
    Abstract: A toner for a two-component developer comprising the toner and carrier particles, the developer being used for an oilless fixing-type image forming apparatus comprising a developer carrier rotatable at a linear speed of 360-1,680 mm/sec, and a developer adjusting member extending in a lateral direction parallel to the rotational axis of the developer carrier and disposed adjacent to the developer carrier to define a gap therebetween of 0.3-1.0 mm, said image forming apparatus being operated so that the amount of the developer conveyed by the developer carrier and passing through the gap per 1 second is 5.0-25.0 g per 1 cm of the lateral width of the gap, the toner comprising a wax dispersed therein and the toner having a coefficient of dynamic friction in the range of 0.18-0.45.
    Type: Application
    Filed: May 31, 2002
    Publication date: June 5, 2003
    Inventors: Hiroaki Matsuda, Kazuyuki Yazaki, Takayuki Koike, Koji Suzuki, Tadashi Kasai, Yutaka Takahashi, Mitsuo Aoki, Naohito Shimota, Akihiro Itoh
  • Publication number: 20030018010
    Abstract: The present invention relates to dextran whose boron content is reduced to a value less than 0.30 &mgr;g/g (dry basis) calculated on the basis of boron atom, a process for producing the same, and dextran with which a container is filled in a solution state. Dextran of the present invention is obtained by treating a boron-containing dextran with a lower alcohol, and said dextran has such a characteristic that deposition is inhibited or the deposition rate is drastically reduced when using it in the form of a solution. Therefore, an isotonic sodium chloride solution of said dextran is suitably used as substitute plasma or external perfusate in an operation.
    Type: Application
    Filed: April 7, 2000
    Publication date: January 23, 2003
    Inventors: HARUO MACHIDA, SHIGEAKI KATO, YUUKI HIRATA, MITSUO AOKI, HIDEKI KOBATAKE
  • Patent number: 6403275
    Abstract: A toner including a resin and a colorant which is dispersed in the toner and which has an average major particle diameter not greater than about 0.5 &mgr;m, wherein the following relationships are satisfied: Ta≦100 (° C.), and (Tb−Ta)≧7.0 (° C.), wherein Ta represents a temperature at which the toner has a melt viscosity of 50,000 Pa·sec and Tb represents a temperature at which the toner has a melt viscosity of 5,000 Pa·sec.
    Type: Grant
    Filed: August 31, 2000
    Date of Patent: June 11, 2002
    Assignee: Ricoh Company, Ltd.
    Inventors: Shinichi Kuramoto, Mitsuo Aoki, Hiroshi Yamashita, Fumihiro Sasaki, Tomio Kondou, Masahide Yamashita, Kazuhito Watanabe, Takashi Okada
  • Publication number: 20020039698
    Abstract: An image formation method includes the steps of charging the surface of an electrophotographic photoconductor, exposing the charged photoconductor to a light image to form a latent electrostatic image on the photoconductor, developing the latent electrostatic image using a two-component developer containing a toner and a carrier to obtain a toner image, and transferring the toner image to an image receiving material directly or via an intermediate transfer member, with the photoconductor showing a surface friction coefficient of 0.40 or less, and the toner having toner particles with an average circularity of 0.930 or more.
    Type: Application
    Filed: July 17, 2001
    Publication date: April 4, 2002
    Applicant: Ricoh Company, Ltd.
    Inventors: Fumihiro Sasaki, Mitsuo Aoki, Yasuaki Iwamoto, Naohito Shimota, Kazuyuki Yazaki, Hiroaki Matsuda, Hiroshi Nakai, Kumi Hasegawa, Shinichiro Yagi, Hiroto Higuchi, Akemi Sugiyama
  • Patent number: 6248488
    Abstract: A method of forming images on an image receiving material including a non-contact thermal fusing image fixing step employs a black toner made of black toner particles, a yellow toner made of yellow toner particles, a magenta toner made of magenta toner particles and a cyan toner made of cyan toner particles, the black toner particles having a greater volume mean diameter than the volume mean diameter of the toner particles of any of the yellow toner, the magenta toner and the cyan toner.
    Type: Grant
    Filed: January 15, 1999
    Date of Patent: June 19, 2001
    Assignee: Ricoh Company, Ltd.
    Inventors: Nobutaka Kinoshita, Mitsuo Aoki, Shinichi Kuramoto, Akira Oyamaguchi, Hiroshi Sugimoto
  • Patent number: 6168894
    Abstract: An image forming method including a new toner fixing method and toner therefor, wherein the method includes two rollers in which a toner image on an image supporting material is fixed by heating at a nipped section of the rollers, wherein one of the rollers which is a fixing roller contacting the toner image includes a metal cylinder having a thickness of not more than 1.0 mm, and the fixing pressure of the two rollers is not more than 1.4×105 Pa, and wherein the toner contains resins including two polyester resins, (A) and (B), and the polyester resin (B) includes discrete domains of the polyester resin (A) which has higher glass transition Tg and higher molecular weight than those of the polyester resin (B) and includes a component insoluble in tetrahydrofuran, and wherein the developed image can be fixed at relative low temperature and in wide temperature range, and the fixed image has excellent image quality and preserving property.
    Type: Grant
    Filed: September 13, 1996
    Date of Patent: January 2, 2001
    Assignee: Ricoh Company, Ltd.
    Inventors: Mitsuo Aoki, Hachiro Tosaka, Hiroyuki Fushimi, Masanori Suzuki, Akihiro Kotsugai
  • Patent number: 6120960
    Abstract: A toner including a colorant and a binder resin, wherein the ratio of a melt viscosity .eta.120 of the toner at 120.degree. C. to a melt viscosity .eta.100 of the toner at 100.degree. C. is greater than 0.06 and less than 0.15. An image forming method is provided which includes the steps of forming a toner image on a receiving material with the toner and heating the toner image to fix the toner image. Provided that the toner image has a gloss y when a heating temperature in the heating step is x, the gloss y preferably changes depending on the heating temperature x such that the relationship between the gloss y and the heating temperature x, y=f(x), is within the range between a line 1, f(x)=0.08x-6, and a line 2, f(x)=0.6x-50.
    Type: Grant
    Filed: May 21, 1999
    Date of Patent: September 19, 2000
    Assignee: Ricoh Company, Ltd.
    Inventors: Mitsuo Aoki, Akira Oyamaguchi, Nobutaka Kinoshita