Patents by Inventor Yoshiaki Okuhama

Yoshiaki Okuhama 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: 7166152
    Abstract: A pretreatment solution for providing a catalyst for electroless plating and a pretreatment method using the solution are provided. The pretreatment solution comprises a silver colloidal solution containing, as essential components, at least the following components (I), (II) and (III): (I) silver colloidal particles, (II) one or more ions selected from an ion of a metal having an electric potential which can reduce a silver ion to metal silver in the solution and an ion oxidized at the time of reduction of the silver ion, and (III) one or more ions selected from a hydroxycarboxylate ion, a condensed phosphate ion and an amine carboxylate ion, the silver colloidal particles (I) being produced by the ion of the metal (II) having an electric potential which can reduce a silver ion to metal silver. When an object to be plated is pretreated by use of the pretreatment solution, provision of an effective catalyst for electroless plating is achieved.
    Type: Grant
    Filed: August 7, 2003
    Date of Patent: January 23, 2007
    Assignee: Daiwa Fine Chemicals Co., Ltd.
    Inventors: Yoshiaki Okuhama, Keigo Obata, Masakazu Yoshimoto, Kim Dong Hyun, Shingo Kitamura, Seiichiro Nakao, Hidenori Tsuji, Hidemi Nawafune
  • Patent number: 7056448
    Abstract: A method for forming a circuit pattern includes at least a step (a) of subjecting a non-conductor to electroless copper plating to form a copper film and a step (b) of etching the copper film so as to form a circuit pattern. As a catalyst for the electroless copper plating, a silver colloidal solution is used containing as essential components at least the following: (I) silver colloidal particles; (II) one or more of ions of metal having an electric potential which can reduce silver ions to metal silver in the solution and/or ions which result from oxidation of the ion at the time of reduction of the silver ions; and (III) one or more of hydroxycarboxylate, condensed phosphate and/or amine carboxylate ions. The silver colloidal particles (I) are produced by the ion (II) of the metal having an electric potential which can reduce silver ions to metal silver. The circuit pattern may be formed on a printed wiring board.
    Type: Grant
    Filed: May 20, 2003
    Date of Patent: June 6, 2006
    Assignee: Daiwa Fine Chemicals Co., Ltd.
    Inventors: Yoshiaki Okuhama, Keigo Obata, Masakazu Yoshimoto, Shingo Kitamura, Seiichiro Nakao, Osamu Masuyama, Hidenori Tsuji
  • Publication number: 20050258134
    Abstract: A method for forming a circuit pattern includes at least a step (a) of subjecting a non-conductor to electroless copper plating to form a copper film and a step (b) of etching the copper film so as to form a circuit pattern. As a catalyst for the electroless copper plating, a silver colloidal solution is used containing as essential components at least the following: (I) silver colloidal particles; (II) one or more of ions of metal having an electric potential which can reduce silver ions to metal silver in the solution and/or ions which result from oxidation of the ion at the time of reduction of the silver ions; and (III) one or more of hydroxycarboxylate, condensed phosphate and/or amine carboxylate ions. The silver colloidal particles (I) are produced by the ion (II) of the metal having an electric potential which can reduce silver ions to metal silver. The circuit pattern may be formed on a printed wiring board.
    Type: Application
    Filed: May 20, 2003
    Publication date: November 24, 2005
    Inventors: Yoshiaki Okuhama, Keigo Obata, Masakazu Yoshimoto, Shingo Kitamura, Seiichiro Nakao, Osamu Masuyama, Hidenori Tsuji
  • Publication number: 20040043153
    Abstract: A pretreatment solution for providing a catalyst for electroless plating and a pretreatment method using the solution are provided.
    Type: Application
    Filed: August 7, 2003
    Publication date: March 4, 2004
    Applicant: Daiwa Fine Chemicals Co., Ltd.
    Inventors: Yoshiaki Okuhama, Keigo Obata, Masakazu Yoshimoto, Kim Dong Hyun, Shingo Kitamura, Seiichiro Nakao, Hidenori Tsuji, Hidemi Nawafune
  • Patent number: 6235093
    Abstract: An aqueous solution for obtaining a noble metal by chemical reduction containing at least one water-soluble compound or complex of a metal selected from the group consisting of gold, platinum, silver, and palladium as a source of the metal to be deposited, and at least one mercapto compound or sulfide compound or a salt thereof as a reducing agent. The reducing agent is typically mercaptoacetic acid, 2-mercaptopropionic acid, 2-aminoethanethiol, 2-mercaptoethanol, glucose cysteine, 1-thioglycerol, sodium mercaptopropanesulfonate, N-acetylmethionine, thiosalicylic acid, 2-thiazoline-2-thiol, 2,5-dimercapto-1,3,4-thiadiazole, 2-benzothiazolethiol, or 2-benzimidazolethiol. They may be used singly or in combination.
    Type: Grant
    Filed: June 28, 1999
    Date of Patent: May 22, 2001
    Assignee: Daiwa Fine Chemicals Co., Ltd.
    Inventors: Yoshiaki Okuhama, Takao Takeuchi, Keigo Obata, Yasuhito Kohashi, Hidemi Nawafune
  • Patent number: 6183545
    Abstract: An aqueous solution for the reductive deposition of metals comprising, besides water, (A) a phosphine of the general formula (1)  in which R1, R2, and R3 denote lower alkyl groups, at least one of which being hydroxy-or amino-substituted lower alkyl group, and (B) a soluble compound of a metal or a compound of a metal solubilized through the formation of a soluble complex by said phosphine.
    Type: Grant
    Filed: June 28, 1999
    Date of Patent: February 6, 2001
    Assignee: Daiwa Fine Chemicals Co., Ltd.
    Inventors: Yoshiaki Okuhama, Takao Takeuchi, Masakazu Yoshimoto, Shigeru Takatani, Emiko Tanaka, Masayuki Nishino, Yuji Kato, Yasuhito Kohashi, Kyoko Kuba, Tetsuya Kondo, Keiji Shiomi, Keigo Obata, Mitsuo Komatsu, Hidemi Nawafune
  • Patent number: 5651873
    Abstract: An electroplating solution (A), comprises an aqueous solution consisting essentially of lead phenolsulfonate: 1 to 250 g/liter in terms of Pb content; tin phenolsulfonate: 0.1 to 250 g/liter in terms of Sn content; phenolsulfonic acid: 20 to 300 g/liter; polyoxyethylene polyoxypropylene alkylamine: 1 to 50 g/liter; a 1-naphthaldehyde derivative: 0.001 to 1 g/liter; and an aldol sulfanilic acid derivative: 0.1 to 30 g/liter; or an aqueous solution (B) consisting essentially of lead methanesulfonate: 1 to 250 g/liter in terms of Pb content; tin methanesulfonate: 0.1 to 250 g/liter in terms of Sn content; methanesulfonic acid: 20 to 300 g/liter; polyoxyethylene polyoxypropylene alkylamine: 1 to 50 g/liter; and an aldol sulfanilic acid derivative: 0.1 to 30 g/liter.
    Type: Grant
    Filed: June 26, 1995
    Date of Patent: July 29, 1997
    Assignees: Mitsubishi Materials Corporation, Daiwa Fine Chemicals Co., Ltd.
    Inventors: Naoki Uchiyama, Masayoshi Kohinata, Akihiro Masuda, Yoshiaki Okuhama, Seishi Masaki, Masakazu Yoshimoto
  • Patent number: 5618404
    Abstract: An electrolytic process for producing lead and tin sulfonates which comprises applying a DC voltage to an anode and a plurality of cathodes in an electrolytic cell and thereby dissolving lead or tin in an electrolytic solution. The electrolytic cell is partitioned by cation- and anion-exchange membranes into anode and cathode chambers. The electrolytic solution is a solution of an organic sulfonic acid, and the anode is lead or tin. The process reduces contents of radioisotopes such as uranium and thorium to a level of less than 50 ppb, and therefore the coatings formed by solder plating using the lead and tin salts in accordance with the invention show radioactive .alpha. particle counts of less than 0.1 CPH/cm.sup.2.
    Type: Grant
    Filed: May 16, 1995
    Date of Patent: April 8, 1997
    Assignee: Daiwa Fine Chemicals Co., Ltd.
    Inventors: Yoshiaki Okuhama, Seishi Masaki, Takao Takeuchi, Yoshiharu Matsuda, Masakazu Yoshimoto
  • 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