Patents by Inventor Akio Tokuyama

Akio Tokuyama 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: 5399208
    Abstract: To treat an iron-based, zinc-based, and an aluminumbased surfaces etc. with zinc phosphate using the same solution, a treating solution is adjusted in concentrations so as to contain a simple fluoride in a range of 200.about.500 mg/l upon converting into a HF concentration and to contain a fluoride complex in a range shown in the following formula; ##EQU1## and also, it is adjusted in an active fluorine concentration so as to be 15.about.130 .mu.A at a value indicated by a silicon electrode meter. Instead of such adjusting, aluminum ions in the treating solution is precipitated in an outside of a treating bath to separate them from the treating solution and then, this treating solution may be returned in to the treating bath.
    Type: Grant
    Filed: February 1, 1993
    Date of Patent: March 21, 1995
    Assignee: Nippon Paint Co., Ltd.
    Inventors: Tamotsu Sobata, Akio Tokuyama, Shoji Shiraishi, Seiichiro Shirahata
  • Patent number: 5380784
    Abstract: The invention relates to formation of a resin film excellent in adhesion with metal or other material and also excellent in alkaline resistance. The invention presents a water-based resin dispersion having an acid value of 0 to 15 obtained by emulsion polymerization of a monomer mixture comprising, in 100 parts by weight of .alpha.,.beta.-ethylenically unsaturated monomer, (1) 1 to 20 parts by weight of .alpha.,.beta.-ethylenically unsaturated monomer with a .beta.-ketoester group, (2) 0.05 to 5 parts by weight of crosslinking .alpha.,.beta.-ethylenically unsaturated monomer with two or more radically polymerizable groups, and (3) the rest of other .alpha.,.beta.-ethylenically unsaturated monomer than (1) and (2), by using a radically polymerizable emulsifier at a ratio of 0.2 to 10 parts by weight against the total of 100 pats by weight of the .alpha.,.beta.-ethylenically unsaturated monomer.
    Type: Grant
    Filed: February 19, 1992
    Date of Patent: January 10, 1995
    Assignee: Nippon Paint Co., Ltd.
    Inventors: Kazuhiko Usuki, Kazuhiko Nishimoto, Akio Tokuyama, Koichi Saito, Manabu Yoshioka
  • Patent number: 5232523
    Abstract: The present inventin concerns a process for phosphating a metal surface comprising treating a metal surface with an acidic aqueous phosphate solution comprising zinc ion, phosphate ion, a phosphating accelerator and particular concentration of colloidal particles having an isoelectric point of 3 or less and an average particle diameter of 0.1.mu. or less, the metal surface being iron-based surface, zinc-based surface or combination thereof and the resulted phosphate coating being excellent in film adhesion, corrosion resistance and especially scab corrosion resistance.
    Type: Grant
    Filed: May 6, 1992
    Date of Patent: August 3, 1993
    Assignee: Nippon Paint Co., Ltd.
    Inventors: Koetsu Endo, Akio Tokuyama, Tamotsu Sobata
  • Patent number: 5221370
    Abstract: A zinc phosphate film on a metal surface is used as a surface-protecting film and an under coating film for coating and so on. The zinc phosphate film is formed by treating a metal surface with an aqueous zinc phosphate solution. The aqueous zinc phosphate solution includes solutions containing a zinc ion in a concentration of more than 2 g/l to 20 g/l, a phosphate ion in a concentration of 5 g/l to 40 g/l, and at least one of silicotungstic acid and a silicotungstate in a concentration of 0.005 g/l to 20 g/l measured in terms of tungsten content.
    Type: Grant
    Filed: June 14, 1990
    Date of Patent: June 22, 1993
    Assignee: Nippon Paint Co., Ltd.
    Inventors: Masahiro Jo, Yasutake Mino, Takamasa Shimizu, Koetsu Endo, Akio Tokuyama, Tamotsu Sobata
  • Patent number: 5211769
    Abstract: To treat an iron-based, zinc-based, and an aluminum-based surfaces etc. with zinc phosphate using the same solution, a treating solution is adjusted in concentrations so as to contain a simple fluoride in a range of 200.about.500 mg/l upon converting into a HF concentration and to contain a fluoride complex in a range shown in the following formula; ##EQU1## and also, it is adjusted in an active fluorine concentration so as to be 15.about.130 .mu.A at a value indicated by a silicon electrode meter. Instead of such adjusting aluminum ions in the treating solution is precipitated in an outside of a treating bath to separate them from the treating solution and then, this treating solution may be returned into the treating bath.
    Type: Grant
    Filed: December 18, 1990
    Date of Patent: May 18, 1993
    Assignee: Nippon Paint Co., Ltd.
    Inventors: Tamotsu Sobata, Akio Tokuyama, Shoji Shiraishi, Seiichiro Shirahata
  • Patent number: 5039363
    Abstract: A process for phosphating the surfaces of iron-based metals, zinc-based metals or combination of such surfaces by treating the metal surfaces with an aqueous acidic zinc-phosphating solution comprising from about 0.1 to about 200 g/l of zinc ion, from about 5 to about 40 g/l of phosphate ion, from about 0.01 to 20.0 g/l as tungsten of soluble tungsten compound and a conversion coating accelerator. The metal surfaces thus phosphated with the solution are suitable for electrocoating.
    Type: Grant
    Filed: May 30, 1990
    Date of Patent: August 13, 1991
    Assignee: Nippon Paint Co., Ltd.
    Inventors: Masahiro Jo, Yasutake Mino, Takamasa Shimizu, Koetsu Endo, Akio Tokuyama, Tamotsu Sobata
  • Patent number: 5039563
    Abstract: Disclosed is a surface treating agent which improves the adhesive properties between a metal surface and a paint layer thereon. The surface treating agent is an acidic aqueous solution comprising zinc ions, nickel ions and phosphate ions, characterized by adding a cyclic metaphosphate thereto in the form of(MPO.sub.3).sub.n wherein M represents a metal atom and n isan integer of at least 4 in a concentration of 20 to 600 mg/l.
    Type: Grant
    Filed: October 20, 1989
    Date of Patent: August 13, 1991
    Assignee: Nippon Paint Co., Ltd.
    Inventors: Koetsu Endo, Akio Tokuyama
  • Patent number: 4501649
    Abstract: The present invention provides a method of controlling an electrocoating bath using an ion exchange resin. The ion exchange resin is maintained in a porous container in a suspended state in the electrocoating bath, and is used in a quantity of not more than the chemical equivalent of excess counter-ion to be removed from the bath. Bath control is easily achieved without any coagulation trouble as often observed in conventional column methods.
    Type: Grant
    Filed: November 2, 1983
    Date of Patent: February 26, 1985
    Assignee: Nippon Paint Co., Ltd.
    Inventors: Nobuo Furuno, Yoshio Ota, Masahiro Itai, Akio Tokuyama, Eiichi Nakano