Patents by Inventor Akio Maruyama

Akio Maruyama 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: 7226711
    Abstract: An object of the present invention is to improve a phenomenon of the life-shortening of the endurance life due to scratch occurring when recesses of a fixed dimple shape are formed on the surface of the surface layer, in order to inhibit the chattering and folding back of a cleaning blade and the fracture of an edge, which occurs because friction between the surface layer of the surface of an electrophotographic photosensitive member and an abutting member is high; and particularly to improve the above described problems, from initial printing through printing on many sheets, which become particularly remarkable when using an electrophotographic photosensitive member with the use of a curable resin that is improved so as to have a high elastic deformation rate for the surface layer, in order to improve the strength of the surface layer, for the purpose of increasing the durability of an electrophotographic photosensitive member.
    Type: Grant
    Filed: September 28, 2005
    Date of Patent: June 5, 2007
    Assignee: Canon Kabushiki Kaisha
    Inventors: Shoji Amamiya, Koichi Nakata, Tatsuya Ikezue, Takahiro Mitsui, Akira Shimada, Hiroki Uematsu, Shuji Ishii, Akio Maruyama
  • Patent number: 7186489
    Abstract: An electrophotographic photosensitive member is disclosed having a cylindrical support and an organic photosensitive layer provided on the cylindrical support. The peripheral surface of the electrophotographic photosensitive member is composed of grooves formed substantially in its peripheral direction and flat portions, and in the grooves, the number of grooves each having a width in the range of from 0.5 ?m to 40 ?m is from 20 to 1,000 lines per 1,000 ?m in width in the generatrix direction of the peripheral surface of the electrophotographic photosensitive member.
    Type: Grant
    Filed: September 14, 2005
    Date of Patent: March 6, 2007
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hiroki Uematsu, Tatsuya Ikezue, Akira Shimada, Takahiro Mitsui, Koichi Nakata, Shuji Ishii, Shoji Amamiya, Akio Maruyama
  • Publication number: 20060019185
    Abstract: An object of the present invention is to improve a phenomenon of the life-shortening of the endurance life due to scratch occurring when recesses of a fixed dimple shape are formed on the surface of the surface layer, in order to inhibit the chattering and folding back of a cleaning blade and the fracture of an edge, which occurs because friction between the surface layer of the surface of an electrophotographic photosensitive member and an abutting member is high; and particularly to improve the above described problems, from initial printing through printing on many sheets, which become particularly remarkable when using an electrophotographic photosensitive member with the use of a curable resin that is improved so as to have a high elastic deformation rate for the surface layer, in order to improve the strength of the surface layer, for the purpose of increasing the durability of an electrophotographic photosensitive member.
    Type: Application
    Filed: September 28, 2005
    Publication date: January 26, 2006
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Shoji Amamiya, Koichi Nakata, Tatsuya Ikezue, Takahiro Mitsui, Akira Shimada, Hiroki Uematsu, Shuji Ishii, Akio Maruyama
  • Publication number: 20060008717
    Abstract: An electrophotographic photosensitive member is disclosed having a cylindrical support and an organic photosensitive layer provided on the cylindrical support. The peripheral surface of the electrophotographic photosensitive member is composed of grooves formed substantially in its peripheral direction and flat portions, and in the grooves, the number of grooves each having a width in the range of from 0.5 ?m to 40 ?m is from 20 to 1,000 lines per 1,000 ?m in width in the generatrix direction of the peripheral surface of the electrophotographic photosensitive member.
    Type: Application
    Filed: September 14, 2005
    Publication date: January 12, 2006
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Hiroki Uematsu, Tatsuya Ikezue, Akira Shimada, Takahiro Mitsui, Koichi Nakata, Shuji Ishii, Shoji Amamiya, Akio Maruyama
  • Publication number: 20050255393
    Abstract: An electrophotographic photosensitive member hard to cause the problem of chatter and wear-out of the cleaning blade and the problem of a rubbing memory, and both a process cartridge and an electrophotographic apparatus having the photosensitive member are provided. The peripheral surface of the photosensitive member has a plurality of dimple-shaped concaves, a 10-point average roughness Rzjis (A) as measured by sweeping along the circumference of the peripheral surface of the photosensitive member is 0.3 to 2.5 ?m, a 10-point average roughness Rzjis (B) as measured by sweeping along the generating line of the peripheral surface of the photosensitive member is 0.3 to 2.
    Type: Application
    Filed: June 17, 2005
    Publication date: November 17, 2005
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Koichi Nakata, Akira Shimada, Tatsuya Ikezue, Takahiro Mitsui, Hiroki Uematsu, Shuji Ishii, Shoji Amamiya, Akio Maruyama
  • Publication number: 20040043312
    Abstract: An electrophotographic photosensitive member is provided by forming a photosensitive layer on an electroconductive support.
    Type: Application
    Filed: May 31, 2002
    Publication date: March 4, 2004
    Inventors: Toshihiro Kikuchi, Akio Maruyama, Hiroki Uematsu
  • Patent number: 6664014
    Abstract: An electrophotographic photosensitive member is constituted by disposing a protective layer and a photosensitive layer on an electroconductive support in this order. The protective layer is characterized by containing an electroconductive particles, fluorine-containing resin particles and a binder resin. The photosensitive layer is suitable for providing an electrophotographic apparatus showing excellent electrophotographic characteristics such as a high photosensitivity and a low residual potential and also providing good image forming properties under any environmental condition, improved pause memory characteristics and a decreased transfer memory.
    Type: Grant
    Filed: May 6, 1997
    Date of Patent: December 16, 2003
    Assignee: Canon Kabushiki Kaisha
    Inventors: Toshihiro Kikuchi, Akio Maruyama, Kazushige Nakamura, Michiyo Sekiya
  • Patent number: 6436597
    Abstract: An electrophotographic photosensitive member has a support and a photosensitive layer formed thereon. The electrophotographic photosensitive member has a surface layer containing a charge-transporting material and a resin obtained by exposing to radiations a compound having an acryloyloxy group or methacryloyloxy group to cure.
    Type: Grant
    Filed: January 6, 1999
    Date of Patent: August 20, 2002
    Assignee: Canon Kabushiki Kaisha
    Inventors: Akio Maruyama, Shoji Amamiya, Michiyo Sekiya, Hiroki Uematsu
  • Patent number: 6416915
    Abstract: An electrophotographic photosensitive member is provided by forming a photosensitive layer on an electroconductive support. The photosensitive layer is provided with particularly excellent durability while retaining good electrophotographic performances when formed as a layer comprising a polymerizate of a hole-transporting compound having at least two chain polymerization function groups in its molecule represented by formula (1) below: &Parenopenst;P1&Parenclosest;aA&Parenopenst;Z—(P2)d)b  (1), wherein A denotes a hole-transporting group, P1 and P2 independently denote a chain polymerization function group and Z denotes a bonding organic group; a, b and d are independently an integer of at least 0 satisfying a+b×d≧2 provided that if a≧2. plural groups P1 can be identical or different; if b≧2, plural groups Z can be identical or different; and if b×d≧2, plural groups P2 can be identical or different.
    Type: Grant
    Filed: November 12, 1999
    Date of Patent: July 9, 2002
    Assignee: Canon Kabushiki Kaisha
    Inventors: Toshihiro Kikuchi, Akio Maruyama, Hiroki Uematsu
  • Patent number: 6372397
    Abstract: An electrophotographic photosensitive member is constituted by a support and a photosensitive layer disposed on the support. The photosensitive layer comprises a charge-transporting material and a resin obtained by radiation curing of a compound having a functional group represented by the following formula (1): wherein Ar denotes a substituted or unsubstituted arylene group and R1 denotes a hydrogen atom or methyl group.
    Type: Grant
    Filed: December 30, 1999
    Date of Patent: April 16, 2002
    Assignee: Canon Kabushiki Kaisha
    Inventors: Akio Maruyama, Toshihiro Kikuchi, Shoji Amamiya, Michiyo Sekiya, Hiroki Uematsu
  • Publication number: 20020018953
    Abstract: An electrophotographic photosensitive member has a support and a photosensitive layer formed thereon. The electrophotographic photosensitive member has a surface layer containing a charge-transporting material and a resin obtained by exposing to radiations a compound having an acryloyloxy group or methacryloyloxy group to cure.
    Type: Application
    Filed: January 6, 1999
    Publication date: February 14, 2002
    Inventors: AKIO MARUYAMA, SHOJI AMAMIYA, MICHIYO SEKIYA, HIROKI UEMATSU
  • Patent number: 6289190
    Abstract: An electrophotographic apparatus includes an electrophotographic photosensitive member; a charger for charging the electrophotographic photosensitive member including a charging member supplied with a voltage and disposed in contact with the photosensitive member so as to form a nip with the photosensitive member to charge the photosensitive member; an exposure device; a developing device; and a transfer device. The photosensitive member includes a surface layer containing a charge-transporting material having an oxidation potential of 0.4-1.0 volt. Charging promoter particles are present at the nip between the photosensitive member and the charging member to injection-charge the photosensitive member. Because of the selection of the charge-transporting material and the presence of the charging promoter particles, the photosensitive member can be effectively injection-charged.
    Type: Grant
    Filed: September 3, 1999
    Date of Patent: September 11, 2001
    Assignee: Canon Kabushiki Kaisha
    Inventors: Shoji Amamiya, Akio Maruyama, Yukio Nagase, Toshihiro Kikuchi, Koichi Suzuki, Harumi Ishiyama
  • Patent number: 6180303
    Abstract: An electrophotographic photosensitive member, process cartridge and electrophotographic apparatus which use the same photosensitive member, and process for producing the same photosensitive member. The electrophotographic photosensitive member, includes a support and photosensitive layer thereon, wherein said photosensitive layer contains at least one of a hole-transporting compound with two or more chain-polymerizing functional groups in the same molecule and the compound hardened by polymerizing or cross-linking the above hole-transporting compound.
    Type: Grant
    Filed: June 11, 1999
    Date of Patent: January 30, 2001
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hiroki Uematsu, Akio Maruyama, Toshihiro Kikuchi
  • Patent number: 6110628
    Abstract: An electrophotographic photosensitive member is comprised of a support and a photosensitive layer formed on the support. The electrophotographic photosensitive member has a surface layer which contains a resin having at least one of the structural units represented by the following formula: ##STR1## wherein the bond represented by a broken line may be present, and when present, m is 4 and when m is 6, n represents an integer of 0 or more, and R.sub.1 and R.sub.2 represent each independently hydrogen, halogen, hydroxy, a substituted or unsubstituted alkyl, a substituted or unsubstituted unsaturated aliphatic hydrocarbon, a substituted or unsubstituted aryl, a substituted or unsubstituted cycloalkyl, a substituted or unsubstituted cyclodienyl, a substituted or unsubstituted alkoxy, a substituted or unsubstituted carbonyl, or a substituted or unsubstituted heterocyclic group.
    Type: Grant
    Filed: July 31, 1998
    Date of Patent: August 29, 2000
    Assignee: Canon Kabushiki Kaisha
    Inventors: Michiyo Sekiya, Hideki Anayama, Akio Maruyama, Shoji Amamiya, Hiroki Uematsu, Hiroyuki Tanaka
  • Patent number: 6016414
    Abstract: An electrophotographic photosensitive member comprising a conductive support, a photosensitive layer and a protective layer containing a setting resin, characterized in that the photosensitive layer contains a resin which has a glass transition point of 170.degree. C. or more. The above image forming apparatus has excellent durability and good image forming properties.
    Type: Grant
    Filed: December 5, 1995
    Date of Patent: January 18, 2000
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hideki Anayama, Akio Maruyama, Kazushige Nakamura
  • Patent number: 5923925
    Abstract: An electrophotographic apparatus has an electrophotographic photosensitive member having a photosensitive layer on an electroconductive support, a charging means provided in contact with the photosensitive member, and image exposure means, a development means, and an image transfer means. The electrophotographic photosensitive member has a surface layer containing electroconductive particles having particle surface treated with a fluorine-containing compound, and a binder resin.
    Type: Grant
    Filed: April 30, 1997
    Date of Patent: July 13, 1999
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kazushige Nakamura, Akio Maruyama, Noboru Kashimura, Shoji Amamiya
  • Patent number: 5890037
    Abstract: An electrophotographic apparatus is constituted by an electrophotographic photosensitive member, and a charger, imagewise exposing light and a developer disposed in this order opposite to the photosensitive member. The photosensitive member has a surface layer which is a charge-injection layer. The charger includes a charging member formed of magnetic particles and disposed contactable to the photosensitive member so as to charge the photosensitive member to at least 80% of a DC voltage supplied to the charging member. The magnetic particles have a volume resistivity in the range of 1.times.10.sup.4 -1.times.10.sup.9 ohm.cm, and the magnetic particles have a surface layer having a volume resistivity of at most 1.times.10.sup.9 ohm.cm.
    Type: Grant
    Filed: June 19, 1995
    Date of Patent: March 30, 1999
    Assignee: Canon Kabushiki Kaisha
    Inventors: Tsutomu Kukimoto, Akio Maruyama, Shuichi Aita, Yoshifumi Hano
  • Patent number: 5838410
    Abstract: An optical modulation element, in which a pixel surrounding a ferroelectric liquid crystal layer and an column shaped orientation layer is formed between a pair of electrodes. The orientation layer is formed by a high-molecular polymer in which an ultrafine granular conductive substance may be dispersed. External voltage applied across the electrodes in response to gradation signals performs gradation drivings.
    Type: Grant
    Filed: April 7, 1994
    Date of Patent: November 17, 1998
    Assignee: Canon Kabushiki Kaisha
    Inventors: Ryoji Fujiwara, Shuzo Kaneko, Akio Maruyama, Tomoko Maruyama, Tomoko Murakami
  • Patent number: 5729801
    Abstract: An electrophotographic apparatus which comprises an electrophotographic photosensitive member, a charging member provided in contact therewith for charging the electrophotographic photosensitive member by being applied with a voltage, a light exposure device, a developing device, and a transfer device, wherein the electrophotographic photosensitive member has a surface layer containing an organic compound having a reduction potential of 0.5 V or lower, and the charging is injection charging.
    Type: Grant
    Filed: August 30, 1996
    Date of Patent: March 17, 1998
    Assignee: Canon Kabushiki Kaisha
    Inventors: Akio Maruyama, Noboru Kashimura, Toshihiro Kikuchi, Kazushige Nakamura, Shoji Amamiya, Hiroyuki Tanaka
  • Patent number: 5708932
    Abstract: This invention relates to a charging system for charging a body to be electrified, comprising a body to be electrified, and a charging member which can be applied with voltage to brush the surface of said body to be electrified and charge it. Wherein the surface of the body to be electrified exhibits a contact angle of 90.degree. or more for water.
    Type: Grant
    Filed: January 7, 1997
    Date of Patent: January 13, 1998
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hideyuki Yano, Akio Maruyama, Yomishi Toshida, Noboru Kashimura, Kazushige Nakamura, Shoji Amamiya, Harumi Ishiyama, Tadashi Furuya