Patents by Inventor Kyoichi Nakamura

Kyoichi Nakamura 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: 4761431
    Abstract: A pre-expanded particle of a propylene resin having two melting temperatures as determined by DSC, the heat of fusion for the peak based on the higher melting temperature being 0.5 to 2.3 cal/g. By using the pre-expanded particles of the propylene resin of the invention, foamed articles having excellent surface appearance, small dimentional shrinkage can be easily obtained without the procedure for giving the internal pressure.
    Type: Grant
    Filed: October 20, 1987
    Date of Patent: August 2, 1988
    Assignee: Kanegafuchi Kagaku Kogyo Kabushiki Kaisha
    Inventor: Kyoichi Nakamura
  • Patent number: 4748191
    Abstract: In a process for preparing pre-expanded particles of a thermoplastic resin which comprises releasing into a low pressure zone an aqueous dispersion of thermoplastic resin particles containing a volatile blowing agent, the dispersion being maintained at an elevated temperature under pressure in a pressure vessel, the improvement which comprises releasing the dispersion through an orifice having a ratio of the length to the average diameter of 4 to 100. According to the present invention, the pre-expanded particles having cells which are uniform in diameter and have an average dimeter of not less than 200 .mu.m can be obtained, and therefore the articles molded in a mold from the pre-expanded particles are small in the shrinkage and strain, are excellent in the appearance, and are increased in the productivity.
    Type: Grant
    Filed: January 30, 1987
    Date of Patent: May 31, 1988
    Assignee: Kanegafuchi Kagaku Kogyo Kabushiki Kaisha
    Inventor: Kyoichi Nakamura
  • Patent number: 4720509
    Abstract: A pre-expanded particle of a propylene resin having two melting temperatures as determined by DSC, the heat of fusion for the peak based on the higher melting temperature being 0.5 to 2.3 cal/g. By using the pre-expanded particles of the propylene resin of the invention, foamed articles having excellent surface appearance, small dimentional shrinkage can be easily obtained without the procedure for giving the internal pressure.
    Type: Grant
    Filed: May 26, 1987
    Date of Patent: January 19, 1988
    Assignee: Kanegafuchi Kagaku Kogyo Kabushiki Kaisha
    Inventor: Kyoichi Nakamura
  • Patent number: 4687641
    Abstract: A process and apparatus for preparing pre-expanded particles of a thermoplastic resin which comprises; heating under an elevated pressure an aqueous dispersion comprising thermoplastic resin particles containing a volatile foaming agent and an aqueous medium in a pressure vessel; releasing the dispersion from the pressure vessel into a space within a sealed low-pressure vessel wherein the pressure is lower than that in the pressure vessel, whereby expanding the thermoplastic resin particles to give pre-expanded particles; and simultaneously recovering the foaming agent volatilized from the thermoplastic resin particles by discharging the foaming agent out of the space in the low-pressure vessel with controlling the pressure in the low-pressure vessel to substantially a given pressure. According to the process, the release of the volatile foaming agent into the air is prevented.
    Type: Grant
    Filed: April 8, 1985
    Date of Patent: August 18, 1987
    Assignee: Kanegafuchi Kogaku Kogyo Kabushiki Kaisha
    Inventors: Hirofumi Maeda, Kyoichi Nakamura, Hisatoshi Fukui
  • Patent number: 4686087
    Abstract: A process and apparatus for preparing pre-expanded particles of a thermoplastic resin which comprises; heating under an elevated pressure an aqueous dispersion comprising thermoplastic resin particles containing a volatile foaming agent and an aqueous medium in a pressure vessel; releasing the dispersion from the pressure vessel into a space within a sealed low-pressure vessel wherein the pressure is lower than that in the pressure vessel and the space is sealed with an aqueous medium which exists in the lower portion of the vessel and communicates with the outside of the vessel, whereby expanding the thermoplastic resin particles to give pre-expanded particles; and sinking the resulting pre-expanded particles under the aqueous medium by means of a rotary impeller provided in the pressure vessel so that the pre-expanded particles are taken out of the low-pressure vessel through the aqueous medium towards the outside of the vessel, while recovering the foaming agent volatilized from the thermoplastic resin par
    Type: Grant
    Filed: February 11, 1985
    Date of Patent: August 11, 1987
    Assignee: Kanegafuchi Kagaku Kogyo Kabushiki Kaisha
    Inventors: Hirofumi Maeda, Kyoichi Nakamura, Toshihiro Hatamoto
  • Patent number: 4617322
    Abstract: A pre-expanded particle suitable for foaming in a mold comprising non-crosslinked linear low density polyethylene which has a characteristic property that an inclination of slope line obtained on a graph when logarithmic values of melt tension of the polyolefin are plotted as ordinate and reciprocals of absolute temperature at which the melt tension is measured are plotted as abscissa is not more than 1,500 is provided. A foamed article produced from the pre-expanded particles has an excellent appearance, a flat surface and good mechanical strength, and is useful for wrapping material, insulating material, a container or a fender of cars.
    Type: Grant
    Filed: June 26, 1985
    Date of Patent: October 14, 1986
    Assignee: Kanegafuchi Kagaku Kogyo Kabushiki Kaisha
    Inventors: Kenichi Senda, Masao Ando, Kyoichi Nakamura, Tatehiko Nishida
  • Patent number: 4540718
    Abstract: A pre-expanded particle suitable for foaming in a mold comprising polyolefin which has a characteristic property that an inclination of slope line obtained on a graph when logarithmic values of melt tension of the polyolefin are plotted as ordinate and reciprocals of absolute temperature at which the melt tension is measured are plotted as abscissa is less than 1,500 is provided. A foamed article produced from the pre-expanded particles has an excellent appearance, a flat surface and good mechanical strength, and is useful for wrapping material, insulating material, a container or a fender of cars.A process for preparing the above-mentioned pre-expanded particles is also disclosed.
    Type: Grant
    Filed: February 29, 1984
    Date of Patent: September 10, 1985
    Assignee: Kanegafuchi Kagaku Kogyo Kabushiki Kaisha
    Inventors: Kenichi Senda, Masao Ando, Kyoichi Nakamura, Tatehiko Nishida
  • Patent number: 4525485
    Abstract: A process for preparing pre-expanded particles of a thermoplastic resin which comprises; heating under an elevated pressure an aqueous dispersion comprising thermoplastic resin particles containing a volatile foaming agent and an aqueous medium in a pressure vessel; releasing the dispersion from the pressure vessel into a space within a sealed low-pressure vessel wherein the pressure is lower than that in the pressure vessel, whereby expanding the thermoplastic resin particles to give pre-expanded particles; and simultaneously recovering the foaming agent volatilized from the thermoplastic resin particles by discharging the foaming agent out of the space in the low-pressure vessel with controlling the pressure in the low-pressure vessel to substantially a given pressure. According to the process, the release of the volatile foaming agent into the air is prevented.
    Type: Grant
    Filed: September 6, 1984
    Date of Patent: June 25, 1985
    Assignee: Kanegafuchi Kagaku Kogyo Kabushiki Kaisha
    Inventors: Hirofumi Maeda, Kyoichi Nakamura, Hisatoshi Fukui
  • Patent number: 4524154
    Abstract: A process for preparing pre-expanded particles of a thermoplastic resin which comprises; heating under an elevated pressure an aqueous dispersion comprising thermoplastic resin particles containing a volatile foaming agent and an aqueous medium in a pressure vessel; releasing the dispersion from the pressure vessel into a space within a sealed low-pressure vessel wherein the pressure is lower than that in the pressure vessel and the space is sealed with an aqueous medium which exists in the lower portion of the vessel and communicates with the outside of the vessel, whereby expanding the thermoplastic resin particles to give pre-expanded particles; and sinking the resulting pre-expanded particles under the aqueous medium by means of a rotary impeller provided in the pressure vessel so that the pre-expanded particles are taken out of the low-pressure vessel through the aqueous medium towards the outside of the vessel, while recovering the foaming agent volatilized from the thermoplastic resin particles by disc
    Type: Grant
    Filed: September 6, 1984
    Date of Patent: June 18, 1985
    Assignee: Kanegafuchi Kagaku Kogyo Kabushiki Kaisha
    Inventors: Hirofumi Maeda, Kyoichi Nakamura, Toshihiro Hatamoto
  • Patent number: 4448901
    Abstract: The mixture of water and the polyolefin resin particles impregnated with a volatile blowing agent are released from the interior of the pressure-resistant container under a constant temperature and constant pressure preferably keeping the partial pressure of the blowing agent constant, through at least one orifice having an area of 0.07 to 300 mm.sup.2, into a low-pressure zone.This invention gives various advantages when applied to the practical process resulting in expanded particles with superior properties which are free of blocking and remarkably uniform in the degree of expansion, and are useful for molding.
    Type: Grant
    Filed: May 13, 1983
    Date of Patent: May 15, 1984
    Assignee: Kanegafuchi Kagaku Kogyo Kabushiki Kaisha
    Inventors: Kenichi Senda, Masao Ando, Kyoichi Nakamura, Kiyoshi Mori, Tatehiko Nishida
  • Patent number: 4298706
    Abstract: Foams of polypropylene resin composition having remarkably improved extrusion foaming characteristics are prepared by a non-crosslinking extrusion foaming process comprising mixing and kneading polypropylene resin and 1,2-polybutadiene resin so that 1,2-polybutadiene resin reacts under the influence of the heat and shearing stress in the extruder, and extruding thereafter.
    Type: Grant
    Filed: September 18, 1979
    Date of Patent: November 3, 1981
    Assignee: Kanegafuchi Kagaku Kogyo Kabushiki Kaisha
    Inventors: Takashi Ueno, Kyoichi Nakamura