Patents by Inventor Katsuji Nakaba

Katsuji Nakaba 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).

  • Publication number: 20030190466
    Abstract: An adhesive sheet for producing semiconductor devices, such as QFNs, can prevent the generation both of wire-bonding defects and mold flashes, and can thereby prevent the production of defective semiconductor devices. The present invention provides an adhesive sheet for producing semiconductor devices which is detachably attached to a lead frame and which comprises a heat resistant substrate and an adhesive layer which is arranged on one surface of the heat resistant substrate, wherein the adhesive layer contains, a thermosetting resin component (a) and a thermoplastic resin component (b); and the weight ratio of the component (a)/the component (b) is 0.3 to 3.
    Type: Application
    Filed: April 2, 2003
    Publication date: October 9, 2003
    Inventors: Katsuji Nakaba, Toshihiro Nakajima, Takeshi Sato, Osamu Oka
  • Patent number: 5512628
    Abstract: This invention is to provide a liquid adhesive of the present invention can be adhered and cured at a relatively low temperature and have sufficient heat resistance and reliability, etc., and an adhesive tape using the same.The liquid adhesive of this invention is obtainable by dissolving (a) a piperazinylethylaminocarbonyl-containing butadiene-acrylonitrile copolymer having a weight average molecular weight of 10,000-200,000, an acrylonitrile content of 5-50% by weight, and an amino equivalent of 500-10,000, represented by the following formula (I): ##STR1## wherein, k, m, and n are molar ratios and taking n as 1, k is a number of 3-175, and m is a number of 0.3 to 93; and (b) a compound having at least two maleimide groups, the ratio of component (b) based on 100 parts by weight of component (a) being in the range of 10 to 900 parts by weight.
    Type: Grant
    Filed: June 5, 1995
    Date of Patent: April 30, 1996
    Assignee: Tomoegawa Paper Co., Ltd.
    Inventors: Yukinori Sakumoto, Takeshi Hashimoto, Katsuji Nakaba, Masaharu Kobayashi, Takeshi Nishigaya, Fumiyoshi Yamanashi
  • Patent number: 5510189
    Abstract: This invention is to provide a liquid adhesive of the present invention can be adhered and cured at a relatively low temperature and have sufficient heat resistance and reliability, etc., and an adhesive tape using the same.The liquid adhesive of this invention is obtainable by dissolving (a) a piperazinylethylaminocarbonyl-containing butadiene-acrylonitrile copolymer having a weight average molecular weight of 10,000-200,000, an acrylonitrile content of 5-50% by weight, and an amino equivalent of 500-10,000, represented by the following formula (I): ##STR1## wherein, k, m, and n are molar ratios and taking n as 1, k is a number of 3-175, and m is a number of 0.3 to 93; and (b) a compound having at least two maleimide groups, the ratio of component (b) based on 100 parts by weight of component (a) being in the range of 10 to 900 parts by weight.
    Type: Grant
    Filed: June 5, 1995
    Date of Patent: April 23, 1996
    Assignee: Tomoegawa Paper Co., Ltd.
    Inventors: Yukinori Sakumoto, Takeshi Hashimoto, Katsuji Nakaba, Masaharu Kobayashi, Takeshi Nishigaya, Fumiyoshi Yamanashi
  • Patent number: 5500294
    Abstract: This invention is to provide a liquid adhesive can be adhered and cured at a relatively low temperature and have sufficient heat resistance and reliability, etc., and an adhesive tape using the same. The liquid adhesive of this invention is obtainable by dissolving(a) a butadiene-acrylonitrile copolymer having piperazinylethylaminocarbonyl groups at both terminals and having a weight average molecular weight of 1,000-50,000, and an acrylonitrile content of 5-50% by weight, represented by the following formula (I): ##STR1## wherein, m=50-95, and n=5-50; and (b) a compound having at least two maleimide groups, the ratio of component (b) based on 100 parts by weight of component (a) being in the range of 10 to 900 parts by weight. This is applied to one or both surfaces of a heat resistant film or one surface of a release film to form an adhesive layer, thereby obtaining an adhesive tape for electronic parts.
    Type: Grant
    Filed: October 20, 1994
    Date of Patent: March 19, 1996
    Assignee: Tomoegawa Paper Co., Ltd.
    Inventors: Yukinori Sakumoto, Takeshi Hashimoto, Katsuji Nakaba, Masaharu Kobayashi, Takeshi Nishigaya, Fumiyoshi Yamanashi
  • Patent number: 5494757
    Abstract: This invention is to provide a liquid adhesive of the present invention can be adhered and cured at a relatively low temperature and have sufficient heat resistance and reliability, etc., and an adhesive tape using the same.The liquid adhesive of this invention is obtainable by dissolving (a) a piperazinylethylaminocarbonyl-containing butadiene-acrylonitrile copolymer having a weight average molecular weight of 10,000-200,000, an acrylonitrile content of 5-50% by weight, and an amino equivalent of 500-10,000, represented by the following formula (I): ##STR1## wherein, k, m, and n are molar ratios and taking n as 1, k is a number of 3-175, and m is a number of 0.3 to 93; and (b) a compound having at least two maleimide groups, the ratio of component (b) based on 100 parts by weight of component (a) being in the range of 10 to 900 parts by weight.
    Type: Grant
    Filed: October 20, 1994
    Date of Patent: February 27, 1996
    Assignee: Tomoegawa Paper Co., Ltd.
    Inventors: Yukinori Sakumoto, Takeshi Hashimoto, Katsuji Nakaba, Masaharu Kobayashi, Takeshi Nishigaya, Fumiyoshi Yamanashi
  • Patent number: 5446080
    Abstract: A liquid adhesive comprising a dispersion of the following component (b) in a solution of the following component (a) in an organic solvent:(a) a piperazinylethylaminocarbonyl-containing butadiene-acrylonitrile copolymer(b) a maleimide compound having at least two maleimide groups.An insulating pattern or insulating layer is formed by applying the liquid adhesive onto an electronic part by a dispensing or screen printing method, followed by thermally curing.
    Type: Grant
    Filed: October 27, 1994
    Date of Patent: August 29, 1995
    Assignee: Tomoegawa Paper Co., Ltd.
    Inventors: Takeshi Shima, Katsuji Nakaba, Masaharu Kobayashi, Yukinori Sakumoto
  • Patent number: 5428113
    Abstract: The piperazinylethylaminocarbonyl-containing butadiene-acrylonitrile copolymer of this invention is a novel substance useful as an adhesive component for adhesive tapes, which tapes are used in the interior of a resin-sealed type semiconductor device. The copolymer has a weight average molecular weight of 10,000-200,000, and is represented by the following general formula (I) and obtained by condensing a carboxyl-containing butadiene-acrylonitrile copolymer having a weight average molecular weight of 10,000-200,000 with N-aminoethylpiperazine in the presence of a phosphite and a pyridine derivative to undergo the amidation. ##STR1## wherein k, m, and n indicate molar proportions, where n is taken as 1, k is a number in the range of 3-175, and m is a number in the range of 0.3-93.
    Type: Grant
    Filed: October 18, 1994
    Date of Patent: June 27, 1995
    Assignee: Tomoegawa Paper Co., Ltd.
    Inventors: Yukinori Sakumoto, Takeshi Hashimoto, Katsuji Nakaba, Masaharu Kobayashi, Takeshi Nishigaya, Fumiyoshi Yamanashi