Patents by Inventor Kenzo Hanawa

Kenzo Hanawa 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: 6004526
    Abstract: A process for producing lithium manganate as a cathode active material for lithium secondary batteries comprising firing raw materials at a rate of temperature rise and/or temperature drop of 150.degree. C./min or more.
    Type: Grant
    Filed: September 9, 1998
    Date of Patent: December 21, 1999
    Assignee: Mitsui & Mining Company, Ltd.
    Inventors: Akiko Sugimoto, Shintaro Ishida, Kenzo Hanawa
  • Patent number: 5951724
    Abstract: A fine particulate polishing agent comprises fine particles of a solid solution composed of single-crystal ceric oxide and silicon dioxide and fine particles of silicon dioxide. A slurry polishing agent comprising the fine particulate polishing agent can be prepared by a method which comprises the steps of mixing, with stirring, single-crystal ceric oxide fine particles, silica sol and a liquid; drying the mixture; subjecting the dried particulate material to a thermal treatment at a high temperature and then cooling the solid solution powder formed by the thermal treatment and composed of single crystal ceric oxide and silicon dioxide; again mixing the powder with silica sol and a liquid; and then subjecting the mixture to deagglomeration using a wet pulverizing mill to give a slurry.
    Type: Grant
    Filed: February 26, 1998
    Date of Patent: September 14, 1999
    Assignee: Mitsui Mining and Smelting Co., Ltd.
    Inventors: Kenzo Hanawa, Naoyoshi Mochizuki, Naruo Ueda, Kazuhiko Kato
  • Patent number: 5938798
    Abstract: A cathodic active material comprises a mixture of graphite particles and electrolytic manganese dioxide particles which are composed of needle-like crystals having an aspect ratio ranging from about 2 to about 20 and an alkaline manganese dioxide cell is provided with a cathode prepared from the cathodic active material. The cathodic active material for dry cells can be prepared by mixing, in advance, carbon powder with manganese dioxide powder in a weight ratio ranging from about 1:100 to about 15:100 and then pulverizing the resulting mixture. The novel cathodic active material for dry cells permits substantial improvement of the resulting dry cell in the high load-discharge quality.
    Type: Grant
    Filed: December 17, 1996
    Date of Patent: August 17, 1999
    Assignee: Mitsui Mining & Smelting Co., Ltd.
    Inventors: Kenzo Hanawa, Sakiko Taenaka, Noriko Hanzawa
  • Patent number: 5938837
    Abstract: Cerium oxide ultrafine particles consist essentially of cerium oxide single crystal grains having a grain size ranging from 10 to 80 nm and the cerium oxide ultrafine particles can be prepared by a method which comprises the steps of mixing, with stirring, an aqueous solution of cerous nitrate with a base in such a mixing ratio that the pH value of the mixture ranges from 5 to 10, then rapidly heating the resulting mixture up to a temperature of 70 to 100.degree. C. and maturing the mixture at that temperature. The cerium oxide ultrafine particles not only have an average particle size ranging from 10 to 80 nm, but also are uniform in the particle size and in the shape.
    Type: Grant
    Filed: September 25, 1996
    Date of Patent: August 17, 1999
    Assignee: Mitsui Mining and Smelting Co., Ltd.
    Inventors: Kenzo Hanawa, Naoyoshi Mochizuki, Naruo Ueda
  • Patent number: 5885369
    Abstract: According to the present invention, the oxidation of the surface of solder particles is inhibited and the generation of solder balls in the reflow soldering process is inhibited. More specifically, the present invention protects the surface of the solder particles from oxidation during all steps, including the storage of a solder powder, formation of a paste from the solder powder, printing, transferring to a reflow oven and reflow soldering, to minimize the oxidation of the solder particles at these steps so that the generation of solder balls is minimized. In addition, the present invention provides a method for making the solder powder and a solder paste using the solder powder. The objective of the present invention is achieved by the solder powder, the particles of which have on the surface thereof an organometallic compound composed of adipic acid and a metal of the solder alloy. This solder powder is produced by reacting particles of the solder alloy powder with vaporized adipic acid.
    Type: Grant
    Filed: August 15, 1997
    Date of Patent: March 23, 1999
    Assignee: Mitsui Mining & Smelting Co., Ltd.
    Inventors: Kenzo Hanawa, Takayuki Araki, Yoshinobu Okamura, Yasuhiro Asano
  • Patent number: 5766279
    Abstract: A fine particulate polishing agent is based on cerium oxide and silicon oxide; a slurry polishing agent comprises the foregoing fine particulate polishing agent which can be prepared by a method which comprises the steps of mixing, with stirring, cerium oxide fine particles, silica sol and a liquid; drying the mixture; mixing the material with a liquid; and then subjecting the mixture to deagglomeration using a wet pulverizing mill to give a slurry. Preferably, the dried particulate material is subjected to a thermal treatment at a high temperature of 150.degree. to 1200.degree. C., preferably 800.degree. to 900.degree. C., thereby to produce a solid solution of cerium oxide and silicon oxide. The slurry polishing agent can ensure the achievement of surface roughness comparable to or superior to that achieved by the colloidal silica polishing agents and a high polishing rate at least comparable to that achieved by the conventional cerium oxide polishing agents.
    Type: Grant
    Filed: September 25, 1996
    Date of Patent: June 16, 1998
    Assignee: Mitsui Mining and Smelting Co., Ltd.
    Inventors: Naruo Ueda, Norikazu Yamamoto, Kenzo Hanawa, Kazuhiko Kato
  • Patent number: 5358660
    Abstract: Magnetic particles for perpendicular magnetic recording, which are hexagonal ferrite particles having a hexagonal platelet shape, and are represented by the formula MM'.sub.x M".sub.y Fe.sub.2x-y+2z O.sub.1+4x+3z (wherein M represents at least one element or a combination of elements selected from Ba, Sr, Ca and Pb; M' is at least one element or a combination of elements selected from Co, Zn and Mn; M" is at least one element or a combination of elements selected from Co, Ti, In, Zn, Mn, Ge, Nb, Zr, Ta, V and Sn, x is a number of z/4 to z, inclusive; y is a number of 0 to (x+z)/3, inclusive; and z is a number of 5.5 to 9.0, inclusive), and has an average particle size of from 0.01 to 0.3 .mu.m. The magnetic particles have a novel crystal structure different from both the magnetoplumbite structure and the spinel structure, even internally of the individual particles.
    Type: Grant
    Filed: July 20, 1992
    Date of Patent: October 25, 1994
    Assignee: Showa Denko Kabushiki Kaisha
    Inventors: Takanori Kidoh, Katsura Ito, Kenzo Hanawa
  • Patent number: 4776885
    Abstract: Short, fine fibers having certain aspect ratios and generally triangular cross-section are mixed with particulate material whereby the fibers form a three dimensional network and the mixture is sintered to provide composites containing scattered and enveloped particulate material, which composites have utility as self-lubricating materials or grinding materials.
    Type: Grant
    Filed: May 5, 1987
    Date of Patent: October 11, 1988
    Assignees: Takeo Nakagawa, Shinsin International Development Corporation
    Inventors: Takeo Nakagawa, Kiyoshi Suzuki, Kenzo Hanawa