Patents by Inventor Masanari Fujita

Masanari Fujita 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: 20070025772
    Abstract: An image-forming device including a plurality of supporting rollers, a photosensitive belt, a pressing roller, an intermediate roller, and a charging roller. The plurality of supporting rollers includes a preselected supporting roller The photosensitive belt is circularly movably supported on the plurality of supporting rollers The pressing roller is disposed to contact the photosensitive belt and to press the preselected supporting roller through the photosensitive belt. The intermediate roller is disposed away from the photosensitive belt and to contact the pressing roller. The intermediate roller is rotatable following rotation of the pressing roller. The charging roller is disposed to contact both the photosensitive belt and the intermediate roller and to press the preselected supporting roller through the photosensitive belt. The charging roller is rotatable following rotation of the intermediate roller to thereby charge the photosensitive belt.
    Type: Application
    Filed: July 31, 2006
    Publication date: February 1, 2007
    Inventors: Yasuo Takuma, Masashi Yamamoto, Masanari Fujita
  • Patent number: 7142794
    Abstract: A metal holder has a V-shape in cross-section formed by two arm sections. PET sheets are attached to mutually opposed surfaces of respective arm sections, and part of each PET sheet extends toward the electrically-conductive roller beyond the arm section. Flocked sheets are attached to the surfaces of the respective PET sheets opposite the electrically-conductive roller, and contact the electrically-conductive roller.
    Type: Grant
    Filed: January 19, 2005
    Date of Patent: November 28, 2006
    Assignee: Ricoh Printing Systems, Ltd.
    Inventors: Masanari Fujita, Kazuhiro Wakamatsu, Masahiko Saito, Masashi Yamamoto, Yasuo Takuma
  • Publication number: 20060165438
    Abstract: An image forming apparatus includes a photosensitive member being movable in a predetermined direction; a charging roller that charges a surface of the photosensitive member; and a static pre-eliminator that eliminates static electricity by irradiating the surface of the photosensitive member with light, the static pre-eliminator located in an upstream side of the charging roller in a direction of movement of the photosensitive member; wherein an arrangement and an exposure amount of the static pre-eliminator are set to satisfy E?0.025×exp(t/?) where ? is a residual time constant of a photo carrier generated in the photosensitive member by the static pre-eliminator, t is a time period from a time when the photosensitive member passes through the static pre-eliminator to a time when the photosensitive member is charged by the charging roller, and E is a normalized exposure amount of the static pre-eliminator.
    Type: Application
    Filed: January 24, 2006
    Publication date: July 27, 2006
    Applicant: RICOH PRINTING SYSTEMS, LTD.
    Inventors: Yasuo Takuma, Masashi Yamamoto, Masanari Fujita
  • Publication number: 20050169661
    Abstract: A metal holder has a V-shape in cross-section formed by two arm sections. PET sheets are attached to mutually opposed surfaces of respective arm sections, and part of each PET sheet extends toward the electrically-conductive roller beyond the arm section. Flocked sheets are attached to the surfaces of the respective PET sheets opposite the electrically-conductive roller, and contact the electrically-conductive roller.
    Type: Application
    Filed: January 19, 2005
    Publication date: August 4, 2005
    Inventors: Masanari Fujita, Kazuhiro Wakamatsu, Masahiko Saito, Masashi Yamamoto, Yasuo Takuma
  • Patent number: 6300412
    Abstract: This invention relates to a process for preparing rubber-modified aromatic vinyl resin compositions by polymerizing a raw material solution containing 3 to 20% by weight of rubbery polymer, 50 to 97% by weight of an aromatic vinyl monomer, and 0 to 30% by weight of a solvent until the conversion of said aromatic vinyl monomer falls in the range from 30 to 70%, adding a (meth)acrylate monomer or its mixture with other monomers to the reaction mixture so that the ratio by weight of the aromatic vinyl monomer in the reaction mixture to the (meth)acrylate monomer becomes 85/15 to 50/50, continuing the polymerization, and devolatilizing to remove the unreacted monomers, solvent, and the like. It is possible by this process to prepare easily and economically rubber-modified aromatic vinyl resin compositions of easy processability, good surface properties in respect to appearance and scratch resistance, and good balance between impact resistance and rigidity.
    Type: Grant
    Filed: January 7, 2000
    Date of Patent: October 9, 2001
    Assignee: Nippon Steel Chemical Co., Ltd.
    Inventors: Yasuji Shichijo, Masanari Fujita
  • Patent number: 6160052
    Abstract: Provided is a rubber-modified aromatic vinyl resin composition, wherein(a) 4 to 20% by weight of a rubber-like polymer is contained,(b) the rubber-like polymer is dispersed in the aromatic vinyl polymer in the form of grains, and the dispersed grains have a weight-average grain diameter falling in a range of 0.4 to 0.8 .mu.m,(c) the dispersed grains have 1.0 .mu.m or less of a 5% value and 0.2 .mu.m or more of a 95% value in a cumulative grain diameter distribution on a weight basis,(d) a ratio of toluene-insoluble matters to a rubber component each of which is contained in the said composition falls in a range of 1.0 to 2.5, and(e) 0.005 to 0.5% by weight of a silicone oil or the mixed oil of the same amount of silicone oil and a fluorine compound oil of 0.0002 to 0.03% by weight is contained in the said composition. The rubber-modified aromatic vinyl resin composition described above is excellent in a balance between an impact resistance and a rigidity, and has an excellent gloss.
    Type: Grant
    Filed: April 21, 1998
    Date of Patent: December 12, 2000
    Assignee: Nippon Steel Chemical Co., Ltd.
    Inventors: Masayuki Nozawa, Masanari Fujita, Yasuji Shichijo
  • Patent number: 6031050
    Abstract: A rubber-modified styrenic resin composition obtained by graft-polymerizing a styrenic monomer dissolving a rubber-like polymer, wherein(1) the rubber-like polymer is dispersed in a styrenic polymer matrix in the form of particles having a volume average particle diameter falling in the range of 0.5 to 1.6 .mu.m,(2) the dispersed particles of said rubber-like polymer are of a salami structure in which a part of the styrenic polymer having a number average particle diameter falling in the range of 0.13 .mu.m or more and up to 0.20 .mu.m and a particle diameter distribution falling in the range of 1.15 to 1.35 is dispersed and included in the rubber-like polymer particles, and(3) the dispersed particles of said rubber-like polymer have a swelling ratio falling in the range of 7 to 12 in toluene.The rubber-modified styrenic resin composition of the present invention is excellent in mechanical strength, a gloss and a coloring property and has a good balance between them.
    Type: Grant
    Filed: August 22, 1997
    Date of Patent: February 29, 2000
    Assignee: Nippon Steel Chemical Co., Ltd
    Inventors: Masayuki Nozawa, Masanari Fujita, Yasuji Shichijo
  • Patent number: 5747593
    Abstract: An object of the present invention is to provide a process for producing rubber-modified styrene resins in which a distribution of the diameters of the rubber particles is narrow and the impact resistance is well balanced with the elastic modulus. The constitution thereof is characterized in that an aromatic monovinyl series monomer, a rubbery polymer and a styrene polymer are mixed and dissolved, and the mixed solution is adjusted so that the relation of the content R (wt. %) of the rubbery polymer contained in said mixed solution with the content Ps (wt. %) of the styrene polymer satisfies 0.2<Ps/R<3; the solution is further subjected to pre-heating treatment to maintain the conditions before rubber phase inversion, and then rubber phase inversion is carried out in a plug flow type reactor followed by polymerizing to enhance the polymerization conversion rate in the following plug flow type reactor.
    Type: Grant
    Filed: March 22, 1996
    Date of Patent: May 5, 1998
    Assignee: Nippon Steel Chemical Co., Ltd.
    Inventors: Masayuki Nozawa, Yasuji Shichijo, Masanari Fujita
  • Patent number: 5349012
    Abstract: Rubber-modified styrene resins with excellent impact resistance are prepared by formulating a feed from a styrene-based monomer, or a mixture thereof with comonomers and high-viscosity rubber, an organic peroxide, and, if necessary, all inert organic solvent, preheating and continuously supplying the feed to one end of a plug flow type reactor equipped with an agitator, performing the preliminary polymerization to a conversion sufficiently high for the transformation of the rubber in the feed into particles while controlling the weight average particle diameter of the rubber particles to 0.8 to 5 .mu.m, withdrawing the prepolymerized feed from the other end of the reactor, and supplying it to a following plug flow type reactor for continuous enhancement of tile conversion.
    Type: Grant
    Filed: June 25, 1993
    Date of Patent: September 20, 1994
    Assignee: Nippon Steel Chemical Co., Ltd.
    Inventors: Toshio Fujita, Masanari Fujita, Naoto Takeda, Koji Hirashima
  • Patent number: 5244977
    Abstract: A feed containing 100 parts by weight of reactants consisting of 88 to 98% by weight of a styrene-based monomer or its mixture with other comonomers and 2 to 12% by weight of high-viscosity rubber with a viscosity of 400 to 2,000 centipoises in a 5% by weight styrene solution at 25.degree. C., 0.01 to 0.2 part by weight of an organic peroxide, and 0 to 30 parts by weight of an inert organic solvent is supplied continuously to the first complete mixing type reactor where it is polymerized under the condition prevailing before the rubber phase inversion, the initial reaction mixture is withdrawn continuously and supplied to the second complete mixing type reactor where the rubber is transformed into particles with the conversion of the monomers in the reactants held at 40% by weight or less, and the conversion is raised in the following reactor to yield impact-resistant rubber-modified styrene resins containing rubber particles with a weight average particle diameter of 1.5 to 4 .mu.m.
    Type: Grant
    Filed: October 31, 1990
    Date of Patent: September 14, 1993
    Assignee: Nippon Steel Chemical Co., Ltd.
    Inventors: Akifumi Hayakawa, Masanari Fujita, Hiroyuki Shibata, Yoshitaka Sakamaki