Patents by Inventor Yukiyoshi Okada

Yukiyoshi Okada 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: 4673470
    Abstract: A tin, lead, or tin-lead alloy plating bath comprising, as essential ingredients, an alkali metal salt, and a soluble divalent tin compound or/and a lead compound, all of an aliphatic or aromatic sulfocarboxylic acid of the general formula ##STR1## wherein R is a C.sub.1-4 hydrocarbon radical, M.sub.1 is a hydrogen atom or alkali metal atom, M.sub.2 is an alkali metal atom, and X.sub.1 and X.sub.2 are each a hydrogen atom, OH, COON, or SO.sub.3 N (where N represents a hydrogen atom or alkali metal atom).
    Type: Grant
    Filed: February 21, 1986
    Date of Patent: June 16, 1987
    Assignees: Keigo Obata, Nobuyasu Dohi, Daiwa Fine Chemicals Co., Ltd., Ishihara Chemical Co., Ltd.
    Inventors: Keigo Obata, Nobuyasu Dohi, Yoshiaki Okuhama, Seishi Masaki, Yukiyoshi Okada, Masakazu Yoshimoto
  • Patent number: 4555314
    Abstract: A tin-lead alloy plating bath based on a principal plating bath comprising an alkanesulfonic or alkanolsulfonic acid and both bivalent tin and lead salts thereof is characterized by the addition of a guanamine compound having the general formula ##STR1## wherein R.sub.1 and R.sub.2, which may be the same or different, represent each a hydrogen atom, C.sub.1-18 straight- or branched-chain alkyl radical, C.sub.1-18 straight- or branched-chain alkoxy-lower alkyl radical, or a C.sub.3-7 cycloalkyl radical, or R.sub.1 and R.sub.2 may combine to form a carbon cycle or hetero cycle, and A represents a lower alkylene radical.
    Type: Grant
    Filed: September 10, 1984
    Date of Patent: November 26, 1985
    Assignees: Obata, Dohi, Daiwa Fine Chemicals Co. Ltd., Ishihaa Chemical Co., Ltd.
    Inventors: Keigo Obata, Nobuyasu Dohi, Yoshiaki Okuhama, Seishi Masaki, Yukiyoshi Okada, Tadashi Yoshida
  • Patent number: 4459185
    Abstract: A tin, lead or tin-lead alloy plating bath, which comprises(A) a principal plating bath containing an alkanesulfonic or alkanolsulfonic acid, and either a divalent tin salt or a divalent lead salt thereof or both;(B) at least one of surfactants comprising(a) a cationic surfactant selected from the group consisting of quarternary ammonium salts, alkyl pyridinium salts, alkyl imidazolinium salts and higher alkyl amine salts,(b) an amphoteric surfactant selected from betaines, or(c) a nonionic surfactant selected from the group consisting of condensation products of ethylene oxide and/or propylene oxide with a styrenated phenol, a higher alcohol, an alkylphenol, an alkylnaphthol, a fatty acid amide, a sorbitan or a phosphate; and(C) at least one of levelling agents selected from the group consisting of alkylidene sulfamic acids, quinolinol derivatives, benzotriazole derivatives, dialkylidene o-phenylene diamines, benzaldehyde derivatives, triazine derivatives, salicylic acid derivatives and nitriles.
    Type: Grant
    Filed: September 16, 1983
    Date of Patent: July 10, 1984
    Assignees: Obata, Doni, Daiwa, Fine Chemicals Co., Ltd., Ishibara Chemical Co., Ltd.
    Inventors: Keigo Obata, Nobuyasu Dohi, Yoshiaki Okuhama, Seishi Masaki, Yukiyoshi Okada, Masakazu Yoshimoto