Patents by Inventor Shigeru Sadamatsu

Shigeru Sadamatsu 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: 5037717
    Abstract: A developer for an electrostatic latent image is disclosed, which comprises a carrier powder, a toner powder, and a fine powder that has a particle size smaller than that of the toner powder said fine powder being made of a polymer which is located closer to the carrier side of the triboelectric series than to the toner side. The developer does not cause insufficient cleaning or toner filming on a photoreceptor or electrostatic recording element.
    Type: Grant
    Filed: November 16, 1988
    Date of Patent: August 6, 1991
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Yukihiro Ishii, Takayoshi Aoki, Koichi Tanaka, Shigeru Sadamatsu
  • Patent number: 4943505
    Abstract: A developer for an electrostatic latent image is described, which comprises a toner powder and a fine powder having a particle size smaller than that of the toner powder, said fine powder being made of a polymer obtained by soap-free emulsion polymerization.
    Type: Grant
    Filed: March 6, 1985
    Date of Patent: July 24, 1990
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Takayoshi Aoki, Yukihiro Ishii, Koichi Tanaka, Shigeru Sadamatsu
  • Patent number: 4933253
    Abstract: A developer for an electrostatic latent image is disclosed, which comprises a toner powder and a fine powder of an acrylic homopolymer or copolymer having an average particle size smaller than that of the toner powder. The developer can be easily cleaned off without causing damage to a latent image-forming member.
    Type: Grant
    Filed: March 6, 1985
    Date of Patent: June 12, 1990
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Takayoshi Aoki, Yukihiro Ishii, Koichi Tanaka, Shigeru Sadamatsu
  • Patent number: 4365274
    Abstract: A one-dimensional image sensor such as may be used in scanning an original document for use in a copying system and a method for producing the sensor. Integrated drive circuit elements are formed in a relatively small region of a monocrystalline semiconductor substrate. Lead electrodes are formed on the surface of the substrate diverging outwardly from the drive circuit elements. The lead electrodes have at end portions picture element size belt-shaped electrodes. A photoconductive non-crystalline film is formed over the belt-shaped electrodes with a wide transmissive electrode layer provided over the photoconductive non-crystalline film layer.
    Type: Grant
    Filed: April 16, 1980
    Date of Patent: December 21, 1982
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Mutsuo Takenouchi, Shigeru Sadamatsu
  • Patent number: 4346159
    Abstract: A photosensitive element for electrophotography comprising an electrically conductive backing member, a photoconductive layer overlying the backing member, and a transparent electrically insulating surface layer on the photoconductive layer, wherein the transparent electrically insulating surface layer contains a charge-retentive material or a layer of a charge-retentive material is interposed between the photoconductive layer and the transparent electrically insulating surface layer so as to form a charge-retentive layer in the boundary between the photoconductive layer and the transparent electrically insulating layer.
    Type: Grant
    Filed: February 14, 1978
    Date of Patent: August 24, 1982
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Shigeru Sadamatsu, Lyon S. Pu, Yoshihisa Ishikawa
  • Patent number: 4315980
    Abstract: An electrophotographic member in which a photoconductive layer and a protective layer are superposed in order on a photoconductive support, wherein the improvement comprises:said protective layer containing at least one metallocene or a compound having at least one metallocene nucleus in its molecular structure.
    Type: Grant
    Filed: April 4, 1980
    Date of Patent: February 16, 1982
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Shigeru Sadamatsu, Kohichi Yamamoto, Kazuaki Ohmi
  • Patent number: 4245022
    Abstract: A xerographic developer including 2 to 10% by weight of abrasive particles having a diameter of 100 to 800.mu., exhibiting no electrophotographic developing effect, substantially no frictional charging, having a low toner retention capacity, and as much fluidity as the carriers employed. Such particles improve the charging properties of the carriers, prevent the attachment or adherence of the toner to the machine parts, improve the surface potential of the light-sensitive member, and lessen or eliminate the deterioration of the light-sensitive member due to the "deletion phenomenon".
    Type: Grant
    Filed: October 12, 1976
    Date of Patent: January 13, 1981
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Shigeru Sadamatsu, Masakatsu Kimura
  • Patent number: 4197119
    Abstract: In an electrophotographic process for the formation of an electrostatic latent image on a photosensitive element for electrophotography produced through the sequential lamination on an electrically conductive substrate of an electrically insulating layer, a photoconductive layer, and an electrically insulating surface layer by repeating a series of steps comprising a first charging; a light exposure of the entire surface; a second charging of a polarity opposite to that of the first charging; and an image-wise exposure to light, wherein the polarity between the first electrical charging and the second electrical charging is changed from positive to negative and vice versa simultaneously (either a positive image or a negative image can be obtained from an original using the same developer).
    Type: Grant
    Filed: November 28, 1977
    Date of Patent: April 8, 1980
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Shigeru Sadamatsu, Kozo Oka
  • Patent number: 4175962
    Abstract: Developer mixtures comprising finely-divided toner particles electrostatically clinging to the surface of carrier particles. The toner particles comprise a colorant and at least about 60 percent by weight, based on the weight of the toner particles, of a resin mixture comprising between about 40 and about 90 parts by weight of a styrene resin and from about 10 to about 60 parts by weight of an epoxy resin. Electrostatographic imaging processes employing said developer mixtures are also disclosed.
    Type: Grant
    Filed: October 12, 1976
    Date of Patent: November 27, 1979
    Assignee: Rank Xerox, Ltd.
    Inventors: Shigeru Sadamatsu, Tooru Nozaki, Yoshihiko Yamada, Tsuneo Noami
  • Patent number: 4170476
    Abstract: A photosensitive material for electrophotography comprising a support having thereon a photoconductive layer and an electrically insulating layer, in which the photoconductive layer is a vacuum-deposited film substantially comprising Se with a surface layer portion of the vacuum-deposited film contacting the electrically insulating layer containing, within a thickness of about 10 .mu. or less, about 1 to about 50% by weight of As and/or Te and about 0.5 to about 1000 ppm of at least one element of Group IIIb of the Periodic Table.
    Type: Grant
    Filed: June 30, 1977
    Date of Patent: October 9, 1979
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Shigeru Sadamatsu, Kozo Oka
  • Patent number: 4078286
    Abstract: Silicone rubber is employed as an outer coating material on a fuser member and is applied to the base member by means of a novel construction which prevents the separation of the outer silicone rubber coating from the roll even when silicone oil is applied thereto. The fuser member comprises a base member, a layer of a heat-resistant resin formed on the base member and a layer of a silicone rubber formed on the heat-resistant resin layer, the silicone rubber being vulcanized after the formation of the layer of silicone rubber on the resin layer. A primer layer may be used between the heat-resistant resin layer and the silicone rubber layer.
    Type: Grant
    Filed: March 14, 1977
    Date of Patent: March 14, 1978
    Assignee: Rank Xerox Ltd.
    Inventors: Koichi Takiguichi, Teruhiko Itami, Shigeru Sadamatsu, Ashihiko Yamada, Masakatsu Kimura
  • Patent number: 3959153
    Abstract: This invention is a method for manufacturing an electrophotographic developer for use in electrophotography or electrostatic recording processes. The developer comprises polymer particles by suspension polymerizing, in an aqueous phase, a polymerization liquid comprising at least one polymerizable vinyltype monomer, a polymerization initiator, and a finely divided dispersion stabilizer either sparingly soluble or insoluble in water and said monomer. Said polymerization liquid is blended prior to suspension polymerization. The improvement includes adding to said liquid, a resinous substance, as a fluidizer which is soluble in the monomer and having a solubility parameter in the range of from 7.8 to 16.1. During the blending, the dispersion stabilizer is uniformly dispersed throughout said polymerization liquid.
    Type: Grant
    Filed: May 28, 1970
    Date of Patent: May 25, 1976
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Shigeru Sadamatsu, Hiroyuki Kaneko, Keitaro Ohe, Daijiro Nishio
  • Patent number: 3941898
    Abstract: A method for developing a latent image bearing member comprising applying a developer thereto, the developer including a toner comprising a pulverized, colored vinylic polymer resin polymerized by adding to the monomer thereof a crosslinking agent 0.005 - 20% by weight of the monomer and a molecular weight control agent 0 - 20% by weight of the monomer.
    Type: Grant
    Filed: January 4, 1974
    Date of Patent: March 2, 1976
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Shigeru Sadamatsu, Toll Nozaki
  • Patent number: 3936183
    Abstract: An electrophotographic copying machine having a cleaning blade with a cleaning surface coated with a material having a friction coefficient less than 0.8 with respect to the surface of the photosensitive member of the machine, the blade having a tensile elasticity of 0.01 to 10 Kg/mm.sup.2 and the cleaning surface thereof facing the direction of advance of the photosensitive member.
    Type: Grant
    Filed: March 4, 1974
    Date of Patent: February 3, 1976
    Assignee: Fuji Xerox Co., Ltd.
    Inventor: Shigeru Sadamatsu