Patents by Inventor Yoshitaro Nakayama

Yoshitaro Nakayama 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: 5876892
    Abstract: An electrophotographic photoreceptor in which the surface of a photosensitive layer has a small friction coefficient without impairing the excellent electrophotographic characteristics and which has an enhanced oil resistance and does not cause light fatigue, the electrophotographic photoreceptor comprising an electroconductive support having formed thereon a photosensitive layer comprising at least a charge-generating agent, a charge-transfer agent and a binder resin, wherein the photosensitive layer contains a polycarbonate copolymer comprising a recurring unit represented by the general formula (I) as the binder resin: ##STR1## and a butadiene compound represented by the general formula (IV) as the charge-transfer agent: ##STR2##
    Type: Grant
    Filed: June 4, 1998
    Date of Patent: March 2, 1999
    Assignees: Shindengen Electric Manufacturing Co., LTD, Yamanashi Electronics Co., LTD.
    Inventors: Kenichi Fujimori, Yoshitaro Nakayama, Mitsuru Noro, Tetsuya Sakuma, Hajime Suzuki
  • Patent number: 5443933
    Abstract: An electrophotographic photoreceptor which is highly sensitive to light having a wavelength in the oscillatory wavelength region of semiconductor laser and responds quickly and is excellent in other electrophotographic characteristics and which consists an electroconductive support, a charge-generating layer and a charge-transfer layer, the two layers being placed on the support, and said charge-transfer layer containing a specific butadiene compound having formula (I); ##STR1## and a monophenol type antioxidant, the weight ratio of the monophenol type antioxidant/the butadiene compound ranging from 5/95 to 40/80.
    Type: Grant
    Filed: September 10, 1993
    Date of Patent: August 22, 1995
    Assignees: Shindengen Electric Manufacturing Co., Ltd., Yamanashi Electronics Co., Ltd., Takasago International Corporation
    Inventors: Kenichi Fujimori, Yoshitaro Nakayama, Takumi Shinohara, Atsushi Iwanami, Toshimitsu Hagiwara, Tohru Kobayashi
  • Patent number: 5061584
    Abstract: An electrophotographic photoreceptor comprising a support having thereon a photosensitive layer, in which said photosensitive layer contains a butadiene compound represented by the following general formula: ##STR1## wherein each of A.sub.1 -A.sub.4, which may be the same or different, is an alkyl group, a hydrazone compound represented by the following general formula [II]: ##STR2## wherein each of B.sub.1 and B.sub.2, which may be the same or different, is an alkyl group, a phenyl group, a benzyl group or a methoxyphenyl group, R.sub.1 is hydrogen, an alkyl group or O-R in which R is a straight-chain or branched alkyl, alkenyl or alkadienyl group having from 5 to 10 carbon atoms or an aralkyl group having from 7 to 10 carbon atoms, and R.sub.2 is an alkyl group, a phenyl group, a methoxy group, an ethoxy group, a benzyl group, a methoxyphenyl group, a tolyl group or a naphtyl group, and a monophenol compound.
    Type: Grant
    Filed: December 15, 1989
    Date of Patent: October 29, 1991
    Assignees: Shindengen Electric Manufacturing Co., Ltd, Yamanashi Electronics Co., Ltd.
    Inventors: Kenichi Fujimori, Yoshitaro Nakayama, Hajime Suzuki, Yoshiko Shima