Patents by Inventor Keio Yamanaka

Keio Yamanaka 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).

  • Zeolite particles retaining silver ions having antibacterial properties
    Patent number: 4911898
    Abstract: Zeolite particles retaining silver ions having bacteriostatic properties on their ion-exchangeable sites in an amount up to 41% of the zeolite's exchange capacity are described.
    Type: Grant
    Filed: December 28, 1988
    Date of Patent: March 27, 1990
    Assignees: Kanebo Limited, Zenji Hagiwara
    Inventors: Zenji Hagiwara, Shigetaka Hoshino, Hiroo Ishino, Saburo Nohara, Kenichi Tagawa, Keio Yamanaka
  • Zeolite particles having bacteriocidal properties
    Patent number: 4911899
    Abstract: Zeolite particles retaining at least one metal ion having bacteriostatic properties on their ion-exchangeable sites in an amount up to 41% of the zeolite's ion exchange capacity are described.
    Type: Grant
    Filed: December 28, 1988
    Date of Patent: March 27, 1990
    Assignees: Kanebo Limited, Zenji Hagiwara
    Inventors: Zenji Hagiwara, Shigetaka Hoshino, Hiroo Ishino, Saburo Nohara, Kenichi Tagawa, Keio Yamanaka
  • Polymer article having an antibacterial property containing zeolite particles therein and the processes for producing same
    Patent number: 4775585
    Abstract: A polymer article containing zeolite particles on which metal ion having a bactericidal property, e.g. Ag, Cu or Zn, is provided by an ion exchange reaction shows an excellent bactericidal effect and durability of the effect, but no deterioration of physical properties of the polymer.The polymer article is produced by admixing zeolite particles previously provided with the metal ion with a polymer or by moulding a zeolite-containing polymer into an article and then treating the article with a metal ion solution.
    Type: Grant
    Filed: January 29, 1987
    Date of Patent: October 4, 1988
    Assignee: Kanebo Ltd./Kanto Chemical Co.
    Inventors: Zenji Hagiwara, Shigetaka Hoshino, Hiroo Ishino, Saburo Nohara, Kenichi Tagawa, Keio Yamanaka
  • Novel aromatic diamine compounds and flame-resistant polyamide compositions containing said compounds
    Patent number: 4144225
    Abstract: Novel N,N,N',N'-tetraacetyl aromatic diamine compounds shown by the general formula (1) ##STR1## wherein R is ##STR2## X is Br or Cl, Y is alkylene group or akylidene group having 1-3 carbon atoms, carbonyl group, sulfonyl group or oxygen atom and m and n is 0 or an integer of 1-4, are produced by reacting 1 mole of aromatic diamine having the general formulaH.sub.2 N--R--NH.sub.2 (2)with at least 4 moles of acetic anhydride. These compounds are used as a flame retardant for polyamides.
    Type: Grant
    Filed: August 12, 1976
    Date of Patent: March 13, 1979
    Assignee: Kanebo, Ltd.
    Inventors: Keio Yamanaka, Kazuo Okamoto, Yoshikatsu Mizukami