Patents by Inventor Masaru Nakagawa

Masaru Nakagawa 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: 5385702
    Abstract: Polybenzoxazole or polybenzothiazole polymer dopes are spun through a spinneret having an orifice density of more than 0.25 per cm.sup.2 to form filaments. The filaments formed then pass through an air gap which has a gas flowing into it at a temperature of between about 5.degree. C. to about 100.degree. C. and at a flow rate between about 0.1 meters/second and about 2.0 meters/second. The filaments cool in the air gap and are then coagulated. During or after coagulation the filaments are combined into one or more fibers. By this method of controlling the temperature in the air gap it is possible to stably spin polybenzoxazole or polybenzothiazole fibers at relatively high final line speeds.
    Type: Grant
    Filed: March 8, 1994
    Date of Patent: January 31, 1995
    Assignee: The Dow Chemical Company
    Inventors: Michael E. Mills, Yoshihiko Teramoto, Timothy L. Faley, Masaru Nakagawa
  • Patent number: 5332789
    Abstract: Polypropylene based resins and compositions comprising the resin having extremely high stiffness, heat resistance and impact strength, with these properties being well-balanced, are provided. The polypropylene based resins are characterized by comprising:(1) a propylene polymer having a content of alpha-olefin other than propylene of not more than 4 mole percent, and the following properties (2), (3) and (4):(2) a pentad fraction (mmmm fraction) measured by .sup.13 C-NMR of not less than 96.0 percent,(3) a main elution fraction peak position of not less than 118.0.degree. C. and a peak half value width of less than 4.0, these values being measured by the temperature raising separation method, and(4) an intrinsic viscosity of not less than 0.5 dl/g, but not more than 5.0 dl/g; and,(5) a rubber content measured by pulse NMR of more than 25 percent.
    Type: Grant
    Filed: February 26, 1993
    Date of Patent: July 26, 1994
    Assignee: Idemitsu Petrochemical Co., Ltd.
    Inventors: Akira Tanaka, Masaru Nakagawa, Hideo Kusuyama, Sueto Miyazaki, Tatsuya Housaki
  • Patent number: 5296185
    Abstract: Polybenzazole polymer dopes are spun into fibers at high speed by passing through a spinneret with proper selection of hole geometry, followed by spin-drawing to a spin-draw ratio of at least 20, washing, taking up and drying. The take up speed is at least about 150 meters per minute, and the fibers are spun in at least 10 km lengths without a break.
    Type: Grant
    Filed: December 3, 1992
    Date of Patent: March 22, 1994
    Assignee: The Dow Chemical Company
    Inventors: Chieh-Chun Chau, Timothy L. Faley, Michael E. Mills, Masaru Nakagawa, Timothy J. Rehg, Myrna Serrano, Ravi Shanker, George J. Quarderer, Jr., Yoshihiko Teramoto
  • Patent number: 5294390
    Abstract: Polybenzazole polymer dopes are spun through a spinneret having more than 2 per cm.sup.2, of orifices in relatively close proximity. The dope filaments formed, then pass through an air gap which has a temperature of 50.degree. to 100.degree. C. and a gas flow sufficient to uniformly reduce the temperature of the dope filaments. The filaments cool in the air gap and are then coagulated.
    Type: Grant
    Filed: December 3, 1992
    Date of Patent: March 15, 1994
    Assignee: The Dow Chemical Company
    Inventors: Steven Rosenberg, George J. Quarderer, Jr., Ashish Sen, Masaru Nakagawa, Timothy L. Faley, Myrna Serrano, Yoshihiko Teramoto, Chieh-Chun Chau
  • Patent number: 5096755
    Abstract: A packaging medium for an electrophotographic photosensitive member contains a conductive material and has a volume resistivity of not more than 10.sup.12 .OMEGA..cm.
    Type: Grant
    Filed: May 19, 1989
    Date of Patent: March 17, 1992
    Assignee: Canon Kabushiki Kaisha
    Inventors: Masaru Nakagawa, Masaaki Hiro, Yoichi Kawamorita
  • Patent number: 5008168
    Abstract: A photosensitive member for electrophotography comprising: an electroconductive substrate and a photosensitive layer disposed thereon comprising an organic photoconductor is provided. the photosensitive layer contains at least, a compound represented by the following formula (I): ##STR1## wherein X.sub.1 denotes a t-butyl or t-amyl group, and X.sub.2 denotes a hydrogen atom, an alkyl group having 1-10 carbon atoms or an alkenyl group having 2-10 carbon atoms; and a compound represented by the following formula (II): ##STR2## wherein X.sub.3 and X.sub.4 respectively denote an alkyl group having 1-10 carbon atoms or an alkenyl group having 2-10 carbon atoms.
    Type: Grant
    Filed: April 17, 1989
    Date of Patent: April 16, 1991
    Assignee: Canon Kabushiki Kaisha
    Inventors: Masaru Nakagawa, Fumio Sumino, Masaaki Hiro, Noboru Kashimura, Shin Nagahara
  • Patent number: 4974964
    Abstract: An apparatus for preparing electrophotographic photosensitive members comprises a means for forming a charge generation layer by coating a charge generation layer coating solution containing two or more kinds of charge-generating materials having different maximum absorption wavelengths, wherein the apparatus further comprises a means for measuring absorbance or transmittance at the respective maximum absorption wavelengths of said coating solution to measure the mixing ratio of the respective charge-generating materials, and a means for controlling the mixing ratio by controlling the feed amount of the respective charge-generating materials.
    Type: Grant
    Filed: November 13, 1989
    Date of Patent: December 4, 1990
    Assignee: Canon Kabushiki Kaisha
    Inventors: Toshiyuki Yoshihara, Yoichi Kawamorita, Tomohiro Kimura, Masaru Nakagawa, Masaaki Hiro
  • Patent number: 4932860
    Abstract: An electrophotographic photosensitive member comprises a photosensitive layer containing an organic photoconductor provided on an electroconductive substrate, wherein said photosensitive layer contains a compound represented by the formula (1) shown below in an amount ranging from 0.1 to 10% by weight based on the total weight of the photosensitive layer added;Formula: ##STR1## wherein R represents ##STR2## X.sub.1, X.sub.2 and X.sub.3 each represent hydrogen atom or methyl group, X.sub.4 represents ##STR3## X.sub.5 represents hydrogen atom, an alkyl group or an alkenyl group.
    Type: Grant
    Filed: October 7, 1988
    Date of Patent: June 12, 1990
    Assignee: Canon Kabushiki Kaisha
    Inventors: Toshiyuki Yoshihara, Masaaki Hiro, Yoichi Kawamorita, Masaru Nakagawa, Fumio Sumino, Noboru Kashimura, Masafumi Hisamura, Tomohiro Kimura
  • Patent number: 4863823
    Abstract: An electrophotographic photosensitive member has a photosensitive layer on an electroconductive support, characterized in that the surface layer contains a fluorine type resin powder and a fluorine type block copolymer.
    Type: Grant
    Filed: April 1, 1988
    Date of Patent: September 5, 1989
    Assignee: Canon Kabushiki Kaisha
    Inventors: Masaaki Hiro, Tomohiro Kimura, Toshiyuki Yoshihara, Yoichi Kawamorita, Masaru Nakagawa
  • Patent number: 4860898
    Abstract: A packaging arrangement and method for the user thereof to protect an electrophotographic photosensitive member which includes a packaging material for covering and protecting the electrophotographic photosensitive member from physical damage and is capable of generating a frictional electrostatic charge of the same polarity as the electrophotographic photosensitive material, whereby the packaging material has a stronger electron acceptor characteristic than the electrophotographic photosensitive material where the electrophotographic photosensitive material possesses a positive charge, and the packaging material has a stronger electron donor characteristic than the electrophotographic photosensitive material where the electrophotographic photosensitive material possesses a negative charge.
    Type: Grant
    Filed: September 9, 1988
    Date of Patent: August 29, 1989
    Assignee: Canon Kabushiki Kaisha
    Inventors: Masaaki Hiro, Masaru Nakagawa, Yoichi Kawamorita, Koji Yamazaki
  • Patent number: 4450467
    Abstract: A gate turn-off thyristor of a short-circuited emitter configuration comprises a semiconductor substrate of a P.sub.E -N.sub.B -P.sub.B -N.sub.E four-layer structure, wherein a P.sub.E -layer is short-circuited through a N.sub.B -layer and an anode. The N.sub.B -layer includes heavily doped regions to which the anode is ohmic contacted with a low resistance. The P.sub.E -layer is provided at a location at least covered by a projection of the N.sub.E -layer. The thickness of the heavily doped regions is greater than that of the P.sub.E -layer. The improved structure assures satisfactory gate turn-off characteristics, although the semiconductor substrate is not doped with a life time killer impurity.
    Type: Grant
    Filed: June 12, 1981
    Date of Patent: May 22, 1984
    Assignee: Hitachi, Ltd.
    Inventors: Takahiro Nagano, Isamu Sanpei, Shuroku Sakurada, Masaru Nakagawa
  • Patent number: 4133736
    Abstract: An apparatus for determining oxygen content in a sealed container is disclosed. The apparatus comprises a sampling tube having a sampling zone which is provided with a pumping means, a change-over valve means for communicating the sampling zone selectively with either inlet or outlet path and a measuring instrument containing an electrode for oxygen determination and air-tightly connected to said sampling tube where one end of the outlet path is opened against the electrode.
    Type: Grant
    Filed: November 22, 1977
    Date of Patent: January 9, 1979
    Assignees: Iijima Products M.F.G. Co., Ltd., Okada Shigyo Co., Ltd.
    Inventors: Masaru Nakagawa, Yasuaki Saito, Hideaki Okada