Patents by Inventor Takehiko Iwaoka

Takehiko Iwaoka 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).

  • Thermosensitive stencil paper and method of producing the same
    Patent number: 7201938
    Abstract: A thermosensitive stencil paper having a thermoplastic resin film and a porous resin layer which is provided on the thermoplastic resin film by coating a porous resin layer formation coating liquid including a water-in-oil emulsion of a resin on the thermoplastic resin film and drying the coating liquid. In addition, the method of producing the above-mentioned thermosensitive stencil paper is also disclosed.
    Type: Grant
    Filed: January 30, 2002
    Date of Patent: April 10, 2007
    Assignees: Ricoh Company, Ltd., Tohoku Ricoh Co., Ltd.
    Inventors: Fumiaki Arai, Takehiko Iwaoka, Yuji Natori, Masanori Rimoto
  • Thermosensitive stencil paper and method of producing the same
    Publication number: 20020102397
    Abstract: A thermosensitive stencil paper having a thermoplastic resin film and a porous resin layer which is provided on the thermoplastic resin film by coating a porous resin layer formation coating liquid including a water-in-oil emulsion of a resin on the thermoplastic resin film and drying the coating liquid. In addition, the method of producing the above-mentioned thermosensitive stencil paper is also disclosed.
    Type: Application
    Filed: January 30, 2002
    Publication date: August 1, 2002
    Inventors: Fumiaki Arai, Takehiko Iwaoka, Yuji Natori, Masanori Rimoto
  • Heat-sensitive stencil and method of fabricating same
    Patent number: 6403150
    Abstract: A heat-sensitive stencil having a thermoplastic resin film, and a porous resin layer formed thereon. The stencil has an air permeability in the range of 1.0 cm3/cm2·sec to 157 cm3/cm2·sec in a portion thereof when the thermoplastic resin film of the portion is perforated to form perforations providing an open ratio SO/SP of at least 0.2, wherein SO represents a total area of the perforations and SP represents the area of the portion. The heat-sensitive stencil is prepared by applying a coating liquid containing the resin of the porous resin layer to the thermoplastic resin film and drying the coating. The coating liquid contains a mixture of a good solvent and a poor solvent less vaporizable than the good solvent so that the porous resin layer is formed after drying.
    Type: Grant
    Filed: July 5, 2000
    Date of Patent: June 11, 2002
    Assignees: Ricoh Company, Ltd., Tohoku Ricoh Co., Ltd.
    Inventors: Masayuki Ohta, Takehiko Iwaoka, Fumiaki Arai, Hiroshi Tateishi, Masanori Rimoto, Hideki Ono, Tetsuo Tanaka, Yuji Natori
  • Thermosensitive stencil paper and method of producing the same
    Patent number: 6372332
    Abstract: A thermosensitive stencil paper having a thermoplastic resin film and a porous resin layer which is provided on the thermoplastic resin film by coating a porous resin layer formation coating liquid including a water-in-oil emulsion of a resin on the thermoplastic resin film and drying the coating liquid. In addition, the method of producing the above-mentioned thermosensitive stencil paper is also disclosed.
    Type: Grant
    Filed: December 3, 1998
    Date of Patent: April 16, 2002
    Assignees: Ricoh Company, Ltd., Tohoku Ricoh Co., Ltd.
    Inventors: Fumiaki Arai, Takehiko Iwaoka, Yuji Natori, Masanori Rimoto
  • Heat-sensitive stencil and method of fabricating same
    Patent number: 6096374
    Abstract: A heat-sensitive stencil having a thermoplastic resin film, and a porous resin layer formed thereon. The stencil has an air permeability in the range of 1.0 cm.sup.3 /cm.sup.2 .multidot.sec to 157 cm.sup.3 /cm.sup.2 .multidot.sec in a portion thereof when the thermoplastic resin film of the portion is perforated to form perforations providing an open ratio S.sub.O /S.sub.P of at least 0.2, wherein S.sub.O represents a total area of the perforations and S.sub.P represents the area of the portion. The heat-sensitive stencil is prepared by applying a coating liquid containing the resin of the porous resin layer to the thermoplastic resin film and drying the coating. The coating liquid contains a mixture of a good solvent and a poor solvent less vaporizable than the good solvent so that the porous resin layer is formed after drying.
    Type: Grant
    Filed: August 24, 1998
    Date of Patent: August 1, 2000
    Assignees: Ricoh Company, Ltd., Tohoku Ricoh Co., Ltd.
    Inventors: Masayuki Ohta, Takehiko Iwaoka, Fumiaki Arai, Hiroshi Tateishi, Masanori Rimoto, Hideki Ono, Tetsuo Tanaka, Yuji Natori
  • Heat-sensitive stencil and method of fabricating same
    Patent number: 5843560
    Abstract: A heat-sensitive stencil having a thermoplastic resin film, and a porous resin layer formed thereon. The stencil has an air permeability in the range of 1.0 cm.sup.3 /cm.sup.2 .multidot.sec to 157 cm.sup.3 /cm.sup.2 .multidot.sec in a portion thereof when the thermoplastic resin film of the portion is perforated to form perforations providing an open ratio S.sub.O /S.sub.P of at least 0.2, wherein S.sub.O represents a total area of the perforations and S.sub.P represents the area of the portion. The heat-sensitive stencil is prepared by applying a coating liquid containing the resin of the porous resin layer to the thermoplastic resin film and drying the coating. The coating liquid contains a mixture of a good solvent and a poor solvent less vaporizable than the good solvent so that the porous resin layer is formed after drying.
    Type: Grant
    Filed: October 30, 1996
    Date of Patent: December 1, 1998
    Assignees: Ricoh Company, Ltd., Tohoku Ricoh Co., Ltd.
    Inventors: Masayuki Ohta, Takehiko Iwaoka, Fumiaki Arai, Hiroshi Tateishi, Masanori Rimoto, Hideki Ono, Tetsuo Tanaka, Yuji Natori
  • Method for producing a large number of copies by means of copying apparatus
    Patent number: 4220699
    Abstract: A method whereby a large number of copies can be produced from a single electrostatic latent image formed on one of a dielectric member, an insulating member or photoconductive member by developing and printing the image by transfer printing in successive operations. The absolute value of a bias voltage impressed on the developing device in developing the electrostatic latent image is gradually reduced until the number of copies produced reaches a specific level, and then progressively increased as the number of copies produced increases for producing copies in numbers which exceed the specific level, whereby copies of a number greater than the number of the specific level can be produced from the same electrostatic latent image.
    Type: Grant
    Filed: May 17, 1978
    Date of Patent: September 2, 1980
    Assignee: Ricoh Co., Ltd.
    Inventors: Tsutomu Ishida, Takehiko Iwaoka