Patents by Inventor Kazumasa Igarashi

Kazumasa Igarashi 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: 6383660
    Abstract: An epoxy resin composition for encapsulating a semiconductor device comprising as essential components (A) an epoxy resin; (B) a phenolic resin; (C) a curing accelerator; and (D) a hollow inorganic filler having an average particle size of 4 to 100 &mgr;m and an average shell thickness of 1.5 &mgr;m or more, wherein the amounts of the component (A) and the component (B) are adjusted such that a total amount of X and Y (X+Y) is 350 or more, wherein X is an epoxy equivalent of the epoxy resin (A), and Y is a hydroxyl group equivalent of the phenolic resin (B); and a semiconductor device comprising a semiconductor element encapsulated by the epoxy resin composition.
    Type: Grant
    Filed: April 6, 2001
    Date of Patent: May 7, 2002
    Assignee: Nitto Denko Corporation
    Inventor: Kazumasa Igarashi
  • Publication number: 20020006986
    Abstract: An epoxy resin composition for encapsulating a semiconductor device comprising as essential components (A) an epoxy resin; (B) a phenolic resin; (C) a curing accelerator; and (D) a hollow inorganic filler having an average particle size of 4 to 100 &mgr;m and an average shell thickness of 1.5 &mgr;m or more, wherein the amounts of the component (A) and the component (B) are adjusted such that a total amount of X and Y (X+Y) is 350 or more, wherein X is an epoxy equivalent of the epoxy resin (A), and Y is a hydroxyl group equivalent of the phenolic resin (B); and a semiconductor device comprising a semiconductor element encapsulated by the epoxy resin composition.
    Type: Application
    Filed: April 6, 2001
    Publication date: January 17, 2002
    Inventor: Kazumasa Igarashi
  • Patent number: 6333139
    Abstract: There are provided a circuit-forming substrate comprising a long stainless steel foil having formed on one surface or both surfaces thereof a polyimide resin layer wholly or partially, and a circuit substrate formed by using the circuit-forming substrate, wherein a conductor layer is finely patterned on the circuit-forming substrate. The circuit-forming substrate sufficiently satisfies low cost, high density and high reliability, scarcely causes warping of the substrate itself, and has excellent workability.
    Type: Grant
    Filed: August 3, 1999
    Date of Patent: December 25, 2001
    Assignee: Nitto Denko Corporation
    Inventors: Toshihiko Omote, Yasuhito Funada, Hideyuki Usui, Masanori Ueno, Kazumasa Igarashi
  • Patent number: 6117616
    Abstract: There are provided a circuit-forming substrate comprising a long stainless steel foil having formed on one surface or both surfaces thereof a polyimide resin layer wholly or partially, and a circuit substrate formed by using the circuit-forming substrate, wherein a conductor layer is finely patterned on the circuit-forming substrate. The circuit-forming substrate sufficiently satisfies low cost, high density and high reliability, scarcely causes warping of the substrate itself, and has excellent workability.
    Type: Grant
    Filed: April 16, 1996
    Date of Patent: September 12, 2000
    Assignee: Nitto Denko Corporation
    Inventors: Toshihiko Omote, Yasuhito Funada, Hideyuki Usui, Masanori Ueno, Kazumasa Igarashi
  • Patent number: 5990546
    Abstract: A semiconductor device in which the space between a semiconductor chip and an auxiliary wiring plate is sealed with resin. The auxiliary wiring plate has insulating layers and on both sides of the routing conductor, the insulating layer on the side of the semiconductor chip has a hole being led from the routing conductor to the electrode of the semiconductor chip, the metal filled in the hole and the metal bump formed so as to protrude from the hole serves as an inner electrode. The semiconductor device can be manufactured by the TAB technique.
    Type: Grant
    Filed: December 29, 1995
    Date of Patent: November 23, 1999
    Assignee: Nitto Denko Corporation
    Inventors: Kazumasa Igarashi, Megumu Nagasawa, Satoshi Tanigawa, Hideyuki Usui, Nobuhiko Yoshio, Hisataka Ito
  • Patent number: 5814894
    Abstract: A semiconductor device capable of preventing the occurrence of defect of electroconductivity, wherein a semiconductor chip 1 equipped with electrodes 11 is mounted on an auxiliary wiring plate 2 in the state of facing the surface of the electrode 11 side, leading conductors 23 are disposed in the inside of the auxiliary wiring plate 2, one end of each leading conductor 23 forms an internal electrode 21 projecting from the surface of the auxiliary wiring plate 2 at the side of mounting the semiconductor chip 1, the other end of the leading conductor 23 forms an external electrode 22 projecting from the surface of the auxiliary wiring plate opposite to the side of mounting the semiconductor chip 1, and each of the internal electrodes 21 is connected to each of the electrodes 11 of the semiconductor chip 1, at least a gap between the semiconductor chip 1 and the auxiliary wiring plate 2 is encapsulated with a heat-welding polyimide resin layer.
    Type: Grant
    Filed: April 4, 1996
    Date of Patent: September 29, 1998
    Assignee: Nitto Denko Corporation
    Inventors: Kazumasa Igarashi, Megumu Nagasawa, Satoshi Tanigawa, Hideyuki Usui, Nobuhiko Yoshio, Hisataka Ito, Tadao Okawa
  • Patent number: 5508742
    Abstract: There is provided a color video camera apparatus (10) which includes an image sensor (11) having a plurality of pixel elements for converting an optical image into an electric image signal, a color filter (12) arranged on the image sensor and having a predetermined mosaic pattern of different colors including complementary colors, an image signal processing circuit (15) for processing the electric image signal to produce at least first and second color difference signals (2R-G) and (2B-G), a variable coefficient generator (20) for generating first and second coefficients (a) and (b) each of which is variable in dependence on the first and second color difference signals, first and second multipliers (19 and 22) for multiplying the first and second color difference signals respectively by the second and first coefficients, and first and second adders (18 and 21 ) for adding outputs of the second and first multipliers to the first and second color difference signals to generate objective third and fourth color
    Type: Grant
    Filed: March 29, 1994
    Date of Patent: April 16, 1996
    Assignee: U.S. Philips Corporation
    Inventors: Jurgen H. T. Geerlings, Kazumasa Igarashi, Hiroshi Kitagawa
  • Patent number: 5294835
    Abstract: A semiconductor device in which a semiconductor chip is encapsulated in an epoxy resin composition comprising (A) an epoxy resin represented by formula (I): ##STR1## wherein R.sub.1, R.sub.2, R.sub.3, and R.sub.4 each represents an alkyl group having from 1 to 4 carbon atoms, and (B) a reaction product obtained by preliminarily reacting a silane compound represented by formula (II): ##STR2## wherein X represents a monovalent organic group having at least one functional group selected from the group consisting of a glycidyl group, an amino group, and a mercapto group; Y represents an alkoxy group having from 1 to 4 carbon atoms; and n represents 0, 1 or 2, with a phenol aralkyl resin represented by formula (III) ##STR3## wherein m represents 0 or a positive integer. The epoxy resin composition has low moisture absorption and low stress to provide a semiconductor device excellent in thermal crack resistance and moisture resistance.
    Type: Grant
    Filed: July 28, 1992
    Date of Patent: March 15, 1994
    Assignee: Nitto Denko Corporation
    Inventors: Kazumasa Igarashi, Hideto Kimura, Megumu Nagasawa, Tsutomu Nishioka, Kazuhiro Ikemura, Hideyuki Usui, Michio Komoto, Haruo Tabata, Satoshi Ito
  • Patent number: 5120573
    Abstract: The present invention provides a process for producing a metal/polyimide composite article such as high-density wiring boards. This metal/polyimide composite article is produced by a method which comprises coating a polyamic acid alkyl ester represented by the following formula on a metallic film and curing it: ##STR1## wherein R.sub.1 and R.sub.2 which may be identical or different each represents an organic group of 1 or more carbon atoms.
    Type: Grant
    Filed: September 27, 1989
    Date of Patent: June 9, 1992
    Assignees: Hitachi, Ltd., Nitto Denko Corporation
    Inventors: Kunio Miyazaki, Osamu Miura, Ryuji Watanabe, Yukio Ookoshi, Toshio Miyamoto, Mikio Aizawa, Kazumasa Igarashi, Amane Mochizuki
  • Patent number: 5053314
    Abstract: A positively photosensitive polyimide composition is disclosed, which composition comprises polyimide having repeating unit represented by formula (I): ##STR1## wherein Ar.sup.1 represents a tetravalent aromatic hydrocarbon group; Ar.sup.2 represents a divalent aromatic hydrocarbon group having an acyloxy group at the ortho-position and/or the meta-position of the aromatic ring; Ar.sup.3 represents a divalent aromatic hydrocarbon group; and the subunit having an amount ratio of m in the repeating unit is present in an amount of at least 20% by weight based on the polyimide. The composition exhibits high photosensitivity in reproduction of a fine pattern and excellent dimensional stability.
    Type: Grant
    Filed: January 9, 1990
    Date of Patent: October 1, 1991
    Assignee: Nitto Denko Corporation
    Inventors: Tsuguo Yamaoka, Amane Mochizuki, Kazumasa Igarashi, Toshihiko Omote
  • Patent number: 4520075
    Abstract: A siloxane-modified polyimide precursor which can be converted into a polyimide having excellent adhesion and moisture resistance is produced by simultaneously polymerizing a diaminosiloxane and a diamine containing no silicon atoms in its molecule with 3,3',4,4'-biphenyltetracarboxylic dianhydride, wherein the diaminosiloxane is used in an amount of 1 to 4 mole % per mole of the total diamino compounds and such that the silicon content in the final reaction product is 0.5 wt % or less. The thus obtained precursor solution is further heat aged to reduce the molecular weight of the precursor so that solution viscosity is decreased to a proper level suitable for coating operation.
    Type: Grant
    Filed: September 25, 1984
    Date of Patent: May 28, 1985
    Assignee: Nitto Electric Industrial Co., Ltd.
    Inventors: Kazumasa Igarashi, Katsuhiko Yamaguchi, Kazuo Iko, Kazuyuki Miki
  • Patent number: 4499252
    Abstract: A process for producing a polyimide precursor having excellent adhesion property and improved moisture resistance by polymerization of an organic tetracarboxylic acid component and a diamine is disclosed. A portion of the organic tetracarboxylic acid is reacted with an aminosilane compound in which H in an amino group is substituted with a monovalent organic group containing a hydrophobic aromatic ring, to produce a silane-modified polycarboxylic acid component and the resulting silane-modified polycarboxylic acid component is polymerized with a diamine together with the residual organic tetracarboxylic acid component.
    Type: Grant
    Filed: March 28, 1984
    Date of Patent: February 12, 1985
    Assignee: Nitto Electric Industrial Co., Ltd.
    Inventors: Kazumasa Igarashi, Katsuhiko Yamaguchi, Munekazu Tanaka