Patents by Inventor Motoyo Wajima

Motoyo Wajima 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: 5768108
    Abstract: A multi-layer wiring structure for mounting electronic devices is provided to be used in an electronic computer, a work station or the like, and more particularly a multi-layer packaging board having microscopic wiring layers, which board has an excellent dimensional stability and a high reliability, and also a method of producing such a board are provided. The multi-layer wiring structure includes a complex of at least two sub-assemblies each having wiring layers formed respectively on opposite sides of a core material of a low thermal expansive metal through an insulation layer in such a manner that the wiring layers correspond in area ratio to each other. The sub-assemblies are connected to one another by conductors via through holes.
    Type: Grant
    Filed: September 27, 1996
    Date of Patent: June 16, 1998
    Assignee: Hitachi, Ltd.
    Inventors: Osamu Miura, Kunio Miyazaki, Akio Takahashi, Motoyo Wajima, Ryuji Watanabe, Takao Miwa, Yuichi Satsu, Shigeo Amagi
  • Patent number: 5472563
    Abstract: The present invention provides a printed circuit board which is high in acid resistance, mechanical strength at high temperature and bond strength, a method for making the printed circuit board and an apparatus used for making the printed circuit board. The technique of the present invention is characterized in that a metallic film having metal particles discretely distributed therein is provided on a roughened surface of copper circuit pattern on an insulating substrate which has been oxidized to form copper oxide and thereafter reduced.
    Type: Grant
    Filed: June 24, 1994
    Date of Patent: December 5, 1995
    Assignee: Hitachi, Ltd.
    Inventors: Kiyonori Kogawa, Nobuaki Ooki, Masami Kawaguchi, Motoyo Wajima, Haruo Akahoshi, Akira Nagai
  • Patent number: 5113477
    Abstract: A plastic optical fiber comprising a core and a clad, said core being formed by an amorphous and optically transparent polymer and said clad being formed by a polymer having a refractive index lower than that of the core by at least 0.3%, at least one of the core and the clad being formed by an amorphous and optically transparent polymer containing metal elements and halogen atoms, is low in light loss and excellent in heat resistance.
    Type: Grant
    Filed: February 20, 1990
    Date of Patent: May 12, 1992
    Assignee: Hitachi, Ltd.
    Inventors: Shuji Eguchi, Noriaki Taketani, Seikichi Tanno, Yoshiaki Okabe, Hiromu Terao, Hideki Asano, Motoyo Wajima, Tomiya Abe
  • Patent number: 5028513
    Abstract: The present invention provide a process for producing printed circuit boards which comprises the steps of(a) roughening a surface of a copper layer formed on an insulating board.(b) coating the roughened surface of copper layer with a photo-resist layer containing a sublimable copper-corrosion inhibitor, exposing the resist layer selectively to actinic rays according to a circuit pattern to form, and developing the resulting resist layer, thereby forming plating-resist coats on circuit-negative pattern portions of the copper layer,(c) heat-treating the plating-resist coats,(d) plating chemically the circuit-corresponding portion with copper,(e) removing the plating-resist coats, and(f) removing the copper layer except the circuit-corresponding portion thereof.
    Type: Grant
    Filed: April 13, 1989
    Date of Patent: July 2, 1991
    Assignees: Hitachi, Ltd., Hitachi Chemical Co., Ltd.
    Inventors: Kanji Murakami, Mineo Kawamoto, Akio Tadokoro, Haruo Akahoshi, Toshikazu Narahara, Ritsuji Toba, Toshiaki Ishimaru, Nobuyuki Hayashi, Motoyo Wajima
  • Patent number: 5021296
    Abstract: A circuit board, which comprises an insulating substrate, a copper wiring having a coarsely roughened surface provided on the insulating substrate, and a copper oxide-reduced layer provided on the coarsely roughened surface of the copper wiring and formed by reduction of copper oxide and electroless plating, the copper oxide-reduced layer having a finely roughed surface and having a deposited layer of at least one of nickel and cobalt, where the copper oxide-reduced layer having a deposited layer of at least one of nickel and cobalt on the surface is roughened in a range of 0.05 to 5 .mu.m in terms of a maximum vertical distance between the top of convex parts and the bottom of concave parts of the copper oxide-reduced layer per .mu.m of the longitudinal distance of the copper oxide-reduced layer, and at least one of nickel and cobalt is deposited in an amount of 5.times.10.sup.-7 to 1.times.10.sup.-4 g/cm.sup.2 on the copper oxide-reduced layer, has a high adhesiveness to an insulating resin.
    Type: Grant
    Filed: September 18, 1989
    Date of Patent: June 4, 1991
    Assignee: Hitachi, Ltd.
    Inventors: Yoshihiro Suzuki, Toshinari Takada, Masahiro Suzuki, Haruo Akahoshi, Akira Nagai, Akio Takahashi, Shigeo Amagi, Toshikazu Narahara, Motoyo Wajima, Kiyonori Kogawa
  • Patent number: 4933228
    Abstract: A thermosetting resin composition comprising a special poly(p-hydroxystyrene) derivative resin and a radical polymerization initiator, and if necessary an epoxy modified polybutadiene, can provide prepregs and laminates having a low dielectric constant, a shorter signalling delay time, good heat resistance and flame retardancy and thus being suitable for producing multilayer printed circuit boards.
    Type: Grant
    Filed: June 19, 1989
    Date of Patent: June 12, 1990
    Assignee: Hitachi, Ltd.
    Inventors: Junichi Katagiri, Akira Nagai, Keiko Tawara, Akio Takahashi, Motoyo Wajima, Toshikazu Narahara, Ryo Hiraga
  • Patent number: 4886858
    Abstract: A thermosetting resin composition comprising a special poly(p-hydroxystyrene) derivative resin and a radical polymerization initiator, and if necessary an epoxy modified polybutadiene, can provide prepregs and laminates having a low dielectric constant, a shorter signalling delay time, good heat resistance and flame retardancy and thus being suitable for producing multilayer printed circuit boards.
    Type: Grant
    Filed: February 17, 1987
    Date of Patent: December 12, 1989
    Assignee: Hitachi, Ltd.
    Inventors: Junichi Katagiri, Akira Nagai, Keiko Tawara, Akio Takahashi, Motoyo Wajima, Toshikazu Narahara, Ryo Hiraga
  • Patent number: 4820549
    Abstract: A photo-curable resist resin composition for electroless plating comprising an epoxy resin having a viscosity of at least 150 poises at 25.degree. C., and at least two glycidyl ether groups in one molecule, the glycidyl ether groups being directly bonded to the aromatic ring as Component A, an oxirane ring-containing compound having a boiling point of at least 140.degree. C. and a molecular weight of not more than 500 as Component B, and a photo-sensitive aromatic onium salt as Component C, wherein the Component A is in an amount of 90 to 40 parts by weight per total 100 parts by weight of the Components A and B, and the Component C is in an amount of 0.
    Type: Grant
    Filed: May 19, 1987
    Date of Patent: April 11, 1989
    Assignee: Hitachi, Ltd.
    Inventors: Kiyoshi Ozaki, Atsushi Mori, Hideo Tsuda, Mineo Kawamoto, Kanji Murakami, Motoyo Wajima
  • Patent number: 4784917
    Abstract: A thermosetting resin composition comprising as essential constituents (a) a prepolymer comprising a poly(p-hydroxystyrene) derivative represented by the general formula ##STR1## wherein A represents a hydrogen or halogen atom or an alkenyl or alkenoyl group having 2 to 4 carbon atoms, m represents a number in the range of from 1 to 4, and n represents a number in the range of from 1 to 100, and (b) a 1,2-polybutadiene or a derivative thereof. By using this novel resin composition and a customary equipment and procedure, it is easy to obtain a tack-free prepreg which is able to produce laminated materials of low permittivity suitable for use in multilayer printed circuit boards improved in peel strength of bonded copper foil, mechanical strengths, flame retardancy, and heat resistance, as compared to conventional printed circuit boards.
    Type: Grant
    Filed: April 22, 1986
    Date of Patent: November 15, 1988
    Assignee: Hitachi, Ltd.
    Inventors: Keiko Tawara, Akira Nagai, Akio Takahashi, Katuo Sugawara, Masahiro Ono, Ritsuro Tada, Motoyo Wajima, Toshikazu Narahara
  • Patent number: 4752641
    Abstract: A thermosetting resin composition comprising (a) a polyfunctional maleimide, (b) at least one member selected from the group consisting of alkenylphenols and alkenylphenol ethers, and (c) an allyl ester of polyvalent carboxylic acid, or cyanuric or isocyanuric acid and a prepolymer obtained by preliminarily heating the thermosetting resin composition can be used as a solventless type varnish for impregnating, e.g. electric windings, or for preparing a prepreg, and can give a cured product with heating at 120.degree.-250.degree. C. having excellent heat resistance of class C (180.degree. C. or higher) and electrical insulating properties.
    Type: Grant
    Filed: April 24, 1987
    Date of Patent: June 21, 1988
    Assignee: Hitachi, Ltd.
    Inventors: Toru Koyama, Hiroko Ohayashi, Junichi Katagiri, Motoyo Wajima, Junji Mukai
  • Patent number: 4738900
    Abstract: Cured resin obtained by polymerization by heating of a thermo-setting, polymerizable composition comprising at least two kinds of polymerizable compounds whose exothermic polymerization temperature ranges at polymerization by heating substantially coincide with each other, for example, an aromatic maleimide compound and an aromatic cyanamide compound, the composition showing a substantially one exothermic polymerization peak at the polymerization by heating, has a good heat resistance, and a laminated, high density wiring board with a good heat resistance, capable of being directly loaded with LSI chips and chip carriers can be obtained, using the composition.
    Type: Grant
    Filed: April 23, 1986
    Date of Patent: April 19, 1988
    Assignee: Hitachi, Ltd.
    Inventors: Masahiro Ono, Akio Takahashi, Katuo Sugawara, Ritsuro Tada, Akira Nagai, Motoyo Wajima, Toshikazu Narahara
  • Patent number: 4710854
    Abstract: A multilayer wiring board structure includes a plurality of conductor layers and insulation layers interleaved between each ones of the conductor layers. The conductor layers includes power (or ground) line layers and signal line layers, and one type of insulation layer having lower relative permittivity and another type of insulation layer having higher relative permittivity is used between power (ground) line layers interposed by signal line layer(s).
    Type: Grant
    Filed: March 10, 1987
    Date of Patent: December 1, 1987
    Assignee: Hitachi, Ltd.
    Inventors: Minoru Yamada, Motoyo Wajima, Akira Masaki, Akio Takahashi, Keiichirou Nakanishi, Katuo Sugawara
  • Patent number: 4661417
    Abstract: A composite of metal and resin comprising a resin layer and a metal layer having a surface roughness of a degree giving a lusterless appearance and a color of olive brown to black closely adhered through said surface to the resin layer is excellent in adhesive strength between the metal and resin layers, the metal layer being excellent in acid resistance, and is suitable for producing printed circuit boards.
    Type: Grant
    Filed: December 31, 1984
    Date of Patent: April 28, 1987
    Assignee: Hitachi, Ltd.
    Inventors: Yoshihiro Suzuki, Nobuhiro Satoh, Motoyo Wajima, Toshikazu Narahara, Takeshi Shimazaki
  • Patent number: 4642161
    Abstract: A method of bonding copper and a resin together is disclosed which comprises forming a copper oxide layer on the surface of copper to be bonded to a resin, reducing the copper oxide layer to metallic copper with a reducing solution, and bonding the metallic copper and the resin together. According to this method, a good acid resistance of the bonding interface and a sufficiently high bonding strength can be obtained.
    Type: Grant
    Filed: January 27, 1986
    Date of Patent: February 10, 1987
    Assignee: Hitachi, Ltd.
    Inventors: Haruo Akahoshi, Kanji Murakami, Motoyo Wajima, Kiyonori Kogawa, Ritsuji Toba, Takeshi Shimazaki
  • Patent number: 4632852
    Abstract: In a process for electroless copper plating in an electroless copper plating solution containing a copper salt, a complexing agent for the copper salt, a reducing agent for the copper salt, and a pH-adjusting agent, a plating film having distinguished mechanical properties can be obtained by adding at least one of soluble inorganic silicon compounds and soluble inorganic germanium compounds and conducting the electroless copper plating by injecting an oxygen-containing gas into the plating solution or by adding an oxidizing agent to the plating solution or by both injection or the oxygen-containing gas and addition of the oxidizing agent thereto. The stability of the electroless copper plating solution can be maintained better thereby and substantially thick plating is possible.
    Type: Grant
    Filed: June 18, 1985
    Date of Patent: December 30, 1986
    Assignee: Hitachi, Ltd.
    Inventors: Haruo Akahoshi, Kanji Murakami, Mineo Kawamoto, Motoyo Wajima, Rituji Toba, Shoji Kawakubo, Akio Tadokoro
  • Patent number: 4610910
    Abstract: A printed circuit board comprising an insulating board deposited with a catalyst having reactivity against electroless plating deposition, a resist for electroless plating provided on the insulating board excepting the part where a circuit is to be formed and a circuit formed by electroless plating, wherein the resist for electroless plating contains a coupling agent having a function of preventing the catalyst from ionizing. A process for producing the printed circuit board in which the insulating board surface excepting the part where a circuit is to be formed is covered with a resist for electroless plating containing a coupling agent having a function of preventing the catalyst from ionizing. Use of said resist for electroless plating can prevent drop of insulation resistance of the insulating board after moisture absorption.
    Type: Grant
    Filed: September 28, 1984
    Date of Patent: September 9, 1986
    Assignee: Hitachi, Ltd.
    Inventors: Mineo Kawamoto, Kanji Murakami, Haruo Akahoshi, Yoichi Matsuda, Motoyo Wajima, Makoto Matsunaga, Shoji Kawakubo, Toyofusa Yoshimura, Haruo Suzuki, Tomio Yoshida
  • Patent number: 4607094
    Abstract: The thermosetting resin composition of the present invention is prepared by mixing an aromatic cyanamide compound with a cyclic ester compound and/or a cyclic amide compound. Although a solventless type composition is preferable, the present invention is not limited thereto. The cured product of the present invention can be prepared by heating and curing said thermosetting resin composition. The obtained cured product of the present invention usually contains melamine rings, isomelamine rings and linear polyester and/or a linear polyamide units.
    Type: Grant
    Filed: February 1, 1985
    Date of Patent: August 19, 1986
    Assignee: Hitachi, Ltd.
    Inventors: Katuo Sugawara, Akio Takahashi, Masahiro Ono, Ritsuro Tada, Motoyo Wajima, Toshikazu Narahara, Akira Nagai
  • Patent number: 4604160
    Abstract: This invention concerns a method for the manufacture of a printed wiring board which particularly proves useful as a printed coil. This method is characterized by the fact that in the work in process which has undergone the step for formation of a conductor circuit and which has not undergone the step for separation of a plating resist, the plating resist and other insulating substratal material are separated for transfer from the surface of the substrate having the conductor circuit formed thereon.Since this method permits formation of an extremely thin insulating layer and a conductor circuit layer thicker than the insulating layer, it enables production of very thin printed wiring board and printed coil having high circuit density in the surfaces of component layers as well as in the direction of superposition of component layers.
    Type: Grant
    Filed: January 8, 1985
    Date of Patent: August 5, 1986
    Assignee: Hitachi, Ltd.
    Inventors: Kanji Murakami, Haruo Akahoshi, Mineo Kawamoto, Motoyo Wajima, Yoichi Matsuda, Kyoji Kawakubo, Minoru Kanechiku, Toyofusa Yoshimura, Makoto Matsunaga
  • Patent number: 4587162
    Abstract: A resin composition comprising a prepolymer of homopolymer or copolymer of isocyanuric acid derivative or cyanuric acid derivative, and a cyclized polybutadiene can give a laminate for multi-layer printed circuit boards excellent in heat resistance, dimensional stability and high-frequency electrical properties.
    Type: Grant
    Filed: July 12, 1985
    Date of Patent: May 6, 1986
    Assignee: Hitachi, Ltd.
    Inventors: Akira Nagai, Akio Takahashi, Katuo Sugawara, Masahiro Ono, Ritsuro Tada, Motoyo Wajima, Toshikazu Narahara
  • Patent number: 4585841
    Abstract: A transparent resin material containing metallic atoms (except for alkali metals) which are ionic-bonded to a vitreous polymeric material constituting the substance of said resin material, in an amount of at least 8% by weight based on the total weight of the resin material, said resin material having a transparency of at least 80% in terms of a light transmittance, and a refractive index n.sub.D.sup.25 of at least 1.55.
    Type: Grant
    Filed: November 1, 1983
    Date of Patent: April 29, 1986
    Assignee: Hitachi, Ltd.
    Inventors: Shuji Eguchi, Noriaki Taketani, Hideki Asano, Motoyo Wajima