Patents by Inventor Tomoyuki Shimada

Tomoyuki Shimada 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: 7838188
    Abstract: A preferred aspect of an electrophotographic photoconductor of the present invention contains a layer containing a hardened material which is prepared by polymerizing (A) a chain-polymerizable group-containing tertiary amine compound in which at least one alkyl group is bound to a nitrogen atom constituting an amine structure through chain polymerization. Another preferred aspect of the electrophotographic photoconductor contains a layer containing a hardened material which is prepared by polymerizing the (A) component, and (B) a chain-polymerizable charge transporting compound through chain polymerization. Still another preferred aspect of the electrophotographic photoconductor contains a layer containing a hardened material which is prepared by polymerizing the (A) component, (B) the chain-polymerizable charge transporting compound, and (C) a trifunctional or more chain-polymerizable compound through chain polymerization.
    Type: Grant
    Filed: March 28, 2007
    Date of Patent: November 23, 2010
    Assignee: Ricoh Company, Ltd.
    Inventors: Nobuya Mori, Kazukiyo Nagai, Tomoyuki Shimada, Tetsuro Suzuki, Tetsuya Toshine
  • Publication number: 20100119964
    Abstract: An electrophotographic photoreceptor including a conductive substrate and a photosensitive layer located overlying the conductive substrate. The photosensitive layer comprises a specific diamine compound.
    Type: Application
    Filed: November 6, 2009
    Publication date: May 13, 2010
    Inventors: Tomoyuki Shimada, Naohiro Toda, Yoshinori Inaba
  • Publication number: 20090324281
    Abstract: An electrophotographic photoreceptor is provided that contains a conductive substrate, an undercoat layer, a charge generation layer, and a charge transport layer, wherein the under coat layer contains a binder resin and multiple inorganic pigments each having different average primary particle diameters in a total amount of from 75 to 86% by weight, the charge generation layer contains a binder resin and a titanyl phthalocyanine pigment having a specific X-ray diffraction spectrum in an amount of from 70 to 85% by weight, the charge transport layer comprises a specific distyryl compound, and the following formulae (2-1) to (2-3) are satisfied: 0.2?(D(F2)/D(G))?0.5??(2-1) 0.2?D(F1)??(2-2) D(F2)?D(F1)??(2-3) wherein D(F1) (?m) and D(F2) (?m) represent average primary particle diameters of the largest and smallest inorganic pigments, respectively, and D(G) (?m) represents an average primary particle diameter of the titanyl phthalocyanine pigment.
    Type: Application
    Filed: June 23, 2009
    Publication date: December 31, 2009
    Applicant: RICOH COMPANY, LTD.
    Inventors: Hiromi Tada, Nozomu Tamoto, Tomoyuki Shimada, Takafumi Iwamoto
  • Publication number: 20090180804
    Abstract: An image forming apparatus including at least an image bearing member having a substrate having a photosensitive layer thereon, the image bearing member to bear a latent electrostatic image on a surface thereof, a charging device to the surface of the image bearing member, an irradiation device to irradiate the surface of the image bearing member with light to form a latent electrostatic image thereon, a development device to develop the latent electrostatic with toner to obtain a developed image, a transfer device to transfer the developed image to a recording medium, and a cleaning device to clean the surface of the image bearing member, wherein the photosensitive layer includes naphthalene tetracarbonic acid diimide derivative as a charge transport material represented by the following Chemical Structure (1): In the Chemical Structure (1), Z represents a group represented by the following Chemical Formula (1): or the following Chemical Formula (2): —R9 ??Chemical Formula (2).
    Type: Application
    Filed: January 9, 2009
    Publication date: July 16, 2009
    Inventors: Eiji Kurimoto, Keisuke Shimoyama, Tomoyuki Shimada, Masafumi Ohta, Yuuji Tanaka
  • Publication number: 20090068577
    Abstract: The present invention provides a naphthalenetetracarboxylic acid diimide derivative represented by the following general formula (1): wherein R1 and R2, which are identical or different, each represent a substituted or non-substituted alkyl group or a substituted or non-substituted aromatic hydrocarbon group; R3 represents an alkyl group having 1 to 8 carbon atoms or an aromatic hydrocarbon group; R4, R5, R6 and R7, which are identical or different, each represent a hydrogen atom, a substituted or non-substituted alkyl group, or a substituted or non-substituted aromatic hydrocarbon group; and R1 and R2 may be linked to form a substituted or non-substituted heterocyclic group including a nitrogen atom; with compounds where all of R1, R2 and R3 are a methyl group, and compounds where both of R1 and R2 are a methyl group and R3 is a 1-octyl group being excluded.
    Type: Application
    Filed: September 5, 2008
    Publication date: March 12, 2009
    Applicant: RICOH COMPANY, LTD.
    Inventors: Masafumi OHTA, Tomoyuki SHIMADA, Yuuji TANAKA, Eiji KURIMOTO, Keisuke SHIMOYAMA
  • Publication number: 20080298840
    Abstract: An electrophotographic photoreceptor including a conductive substrate and a photosensitive layer located overlying the conductive substrate which includes a naphthalenetetracarboxylic acid diimide derivative having a specific formula; and an image forming apparatus and a process cartridge using the electrophotographic photoreceptor are provided.
    Type: Application
    Filed: June 3, 2008
    Publication date: December 4, 2008
    Inventor: Tomoyuki SHIMADA
  • Patent number: 7381511
    Abstract: A photoreceptor including an electroconductive substrate; a photosensitive layer; and optionally a protective layer, wherein an outermost layer thereof includes a filler, an organic compound having an acid value of from 10 to 700 mg KOH/g and at least one compound selected from the group consisting of compounds having the following formulae (1) and (2): wherein R1 (R3) and R2 (R4) independently represent a substituted or an unsubstituted aromatic hydrocarbon group, or a substituted or an unsubstituted alkyl group, and optionally share bond connectivity to form a heterocyclic group including a nitrogen atom; Ar1 (Ar3) and Ar2 (Ar4) independently represent a substituted or a unsubstituted aromatic ring group; k (K) and m (M) independently represent 0 or an integer of from 1 to 3, wherein k (K) and m (M) are not 0 at the same time; and n (n?) represents an integer of from 1 to 3.
    Type: Grant
    Filed: June 1, 2004
    Date of Patent: June 3, 2008
    Assignee: Ricoh Company, Ltd.
    Inventors: Takaaki Ikegami, Tomoyuki Shimada, Yasuo Suzuki, Nozomu Tamoto, Hidetoshi Kami, Yuuji Takana
  • Publication number: 20080102391
    Abstract: A method for preparing a photoreceptor including forming a photosensitive layer overlying an electroconductive substrate; coating a liquid including a radically polymerizable compound to form a protective layer; irradiating the protective layer with light to crosslink the protective layer; and then contacting the protective layer with a fluid, which is selected from the group consisting of supercritical fluids and subcritical fluids and which includes a charge transport material. A photoreceptor prepared by the method. An image forming method, an image forming apparatus and a process cartridge using the photoreceptor.
    Type: Application
    Filed: October 29, 2007
    Publication date: May 1, 2008
    Inventors: Yoshiki YANAGAWA, Michio Kimura, Nozomu Tamoto, Hiromi Tada, Tetsuya Toshine, Tomoyuki Shimada, Chiaki Tanaka
  • Publication number: 20080063962
    Abstract: The present invention provides an electrophotographic photoconductor capable of reducing latent electrostatic image stability defects caused by adhesion/adsorption of an electric discharge product formed by a charger in an image forming process, degradation of charge transportability and cleaning defects caused when removing a residual toner.
    Type: Application
    Filed: September 5, 2007
    Publication date: March 13, 2008
    Inventors: Tetsuya TOSHINE, Chiaki Tanaka, Michio Kimura, Tomoyuki Shimada, Nozomu Tamoto, Yoshiki Yanagawa, Hiromi Tada
  • Publication number: 20070287083
    Abstract: An electrophotographic photoreceptor, including an electroconductive substrate; and a photosensitive layer, located overlying the electroconductive substrate, wherein an outermost layer of the electrophotographic photoreceptor includes an amine compound and a charge transport material, and wherein the amine compound includes an amine site having an electrostatic potential with a dimensionless unit not greater than ?0.27.
    Type: Application
    Filed: June 13, 2007
    Publication date: December 13, 2007
    Inventors: Masanobu Gondoh, Akihiro Sugino, Hideo Nakamori, Shinji Nohsho, Tomoyuki Shimada, Takaaki Ikegami
  • Publication number: 20070269729
    Abstract: An electrophotographic photoreceptor is provided, including an electroconductive substrate and a photosensitive layer located overlying the electroconductive substrate, wherein an outermost layer of the electrophotographic photoreceptor includes a resin including a graft copolymer in which a monomer having a polar group is graft polymerized to a polycarbonate resin, a polyarylate resin, or a copolymer thereof, and a filler; along with an image forming apparatus and a process cartridge using the electrophotographic photoreceptor.
    Type: Application
    Filed: May 18, 2007
    Publication date: November 22, 2007
    Inventors: Hiroshi Ikuno, Masafumi Ohta, Tomoyuki Shimada, Yuuji Tanaka, Hongguo Li
  • Publication number: 20070231720
    Abstract: A preferred aspect of an electrophotographic photoconductor of the present invention contains a layer containing a hardened material which is prepared by polymerizing (A) a chain-polymerizable group-containing tertiary amine compound in which at least one alkyl group is bound to a nitrogen atom constituting an amine structure through chain polymerization. Another preferred aspect of the electrophotographic photoconductor contains a layer containing a hardened material which is prepared by polymerizing the (A) component, and (B) a chain-polymerizable charge transporting compound through chain polymerization. Still another preferred aspect of the electrophotographic photoconductor contains a layer containing a hardened material which is prepared by polymerizing the (A) component, (B) the chain-polymerizable charge transporting compound, and (C) a trifunctional or more chain-polymerizable compound through chain polymerization.
    Type: Application
    Filed: March 28, 2007
    Publication date: October 4, 2007
    Inventors: Nobuya MORI, Kazukiyo Nagai, Tomoyuki Shimada, Tetsuro Suzuki, Tetsuya Toshine
  • Patent number: 7220522
    Abstract: A photoreceptor including a photosensitive layer including a specific diamine compound, or a photoreceptor including an electroconductive substrate; a photosensitive layer located overlying the electroconductive substrate; and optionally a protective layer located overlying the photosensitive layer, wherein an outermost layer of the photoreceptor includes a filler, an organic compound having an acid value of from 10 to 700 mgKOH/g and a specific diamine compound. An image forming method, an image forming apparatus and a process cartridge using the photoreceptor are also provided. A method for manufacturing the photoreceptor including the steps of preparing a coating liquid including the filler, the organic compound, the specific diamine compound and an antioxidant; and coating the coating liquid is also provided.
    Type: Grant
    Filed: March 4, 2004
    Date of Patent: May 22, 2007
    Assignee: Ricoh Company Limited
    Inventors: Takaaki Ikegami, Tomoyuki Shimada, Yasuo Suzuki
  • Patent number: 7183435
    Abstract: The present invention relates to triphenylene compounds useful, for example, in an electrophotographic photoreceptor, and to a method for manufacturing these compounds.
    Type: Grant
    Filed: July 28, 2005
    Date of Patent: February 27, 2007
    Assignee: Ricoh Company, Ltd.
    Inventors: Yuuji Tanaka, Tomoyuki Shimada
  • Patent number: 7122284
    Abstract: An electrophotographic photoconductor has an electroconductive support and a photoconductive layer which is formed thereon and contains at least one resin of a polyurethane resin, a polyester resin, or a polycarbonate resin, each resin having at least a structural unit of formula (1): wherein R1, R2, R3, a, b, and n are the same as those specified in the specification. An electrophotographic image forming apparatus and method, and a process cartridge employ the above photoconductor.
    Type: Grant
    Filed: October 6, 2005
    Date of Patent: October 17, 2006
    Assignee: Ricoh Company, Ltd.
    Inventors: Shinichi Kawamura, Kazukiyo Nagai, Tomoyuki Shimada, Chiaki Tanaka, Michihiko Namba
  • Patent number: 7112392
    Abstract: An electrophotographic photoreceptor including an electroconductive substrate and a photosensitive layer on the electroconductive substrate, wherein the photosensitive layer includes at least a compound having a substituted or unsubstituted alkylamino group and a charge transport material, and wherein an oxidation potential (Eox1) of the substituted or unsubstituted alkylamino group and an oxidation potential (Eox2) of the charge transport material satisfy the following relationship (I): Eox1?Eox2??0.2.
    Type: Grant
    Filed: February 24, 2004
    Date of Patent: September 26, 2006
    Assignee: Ricoh Company, Ltd.
    Inventors: Tomoyuki Shimada, Takaaki Ikegami, Yasuo Suzuki
  • Patent number: 7056633
    Abstract: An electrophotographic photoconductor has an electroconductive support and a photoconductive layer which is formed thereon and contains at least one resin of a polyurethane resin, a polyester resin, or a polycarbonate resin, each resin having at least a structural unit of formula (1): wherein R1, R2, R3, a, b, and n are the same as those specified in the specification. An electrophotographic image forming apparatus and method, and a process cartridge employ the above photoconductor.
    Type: Grant
    Filed: February 12, 2003
    Date of Patent: June 6, 2006
    Assignee: Ricoh Company, Ltd.
    Inventors: Shinichi Kawamura, Kazukiyo Nagai, Tomoyuki Shimada, Chiaki Tanaka, Michihiko Namba
  • Patent number: 7018755
    Abstract: An electrophotographic photoconductor having at least a photosensitive layer on a conductive support, wherein the electrophotographic photoconductor comprising, in the outermost layer thereof: a filler, an organic compound having an acid value of 10–400 mgKOH/g, and at least one of compounds represented by the following general formulas 1 and 2: where R1, R2 are substituted or unsubstituted alkyl groups or aromatic hydrocarbon rings, and may be identical or different. R1, R2 may also be bonded together to form a substituted or unsubstituted heterocycle containing a nitrogen atom. R3, R4, R5 are substituted or unsubstituted alkyl or alkoxy groups, or halogen atoms. Ar is a substituted or unsubstituted aromatic hydrocarbon ring or aromatic heterocycle. n is an integer in the range 2 to 4, and k, l, m are respectively integers in the range 0 to 3. X is an oxygen atom, or a sulfur atom.
    Type: Grant
    Filed: September 23, 2003
    Date of Patent: March 28, 2006
    Assignee: Ricoh Company, Ltd.
    Inventors: Takaaki Ikegami, Tomoyuki Shimada, Yasuo Suzuki, Nozomu Tamoto, Hidetoshi Kami
  • Publication number: 20060035161
    Abstract: An electrophotographic photoconductor has an electroconductive support and a photoconductive layer which is formed thereon and contains at least one resin of a polyurethane resin, a polyester resin, or a polycarbonate resin, each resin having at least a structural unit of formula (1): wherein R1, R2, R3, a, b, and n are the same as those specified in the specification. An electrophotographic image forming apparatus and method, and a process cartridge employ the above photoconductor.
    Type: Application
    Filed: October 6, 2005
    Publication date: February 16, 2006
    Applicant: RICOH COMPANY, LTD.
    Inventors: Shinichi Kawamura, Kazukiyo Nagai, Tomoyuki Shimada, Chiaki Tanaka, Michihiko Namba
  • Publication number: 20060024595
    Abstract: The present invention relates to triphenylene compounds useful, for example, in an electrophotographic photoreceptor, and to a method for manufacturing these compounds.
    Type: Application
    Filed: July 28, 2005
    Publication date: February 2, 2006
    Inventors: Yuuji Tanaka, Tomoyuki Shimada