Patents Assigned to Keigo Obata
  • Tin, lead, or tin-lead alloy plating bath
    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