Patents by Inventor Nobuhito Koga

Nobuhito Koga 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: 8236869
    Abstract: Highly-functionalized, low-viscosity polyether polyols are obtained by dehydration condensation reaction of alcohols. The polyether polyols are obtained by dehydration condensation of glycerin and monohydric and/or dihydric alcohol with the glycerin percentage being more than 50 mol % relative to 100 mol % of the total of the glycerin and alcohol. The glycerin may be crude glycerin obtained by hydrolysis or alcoholysis of natural fat and oils.
    Type: Grant
    Filed: October 25, 2007
    Date of Patent: August 7, 2012
    Assignee: Mitsui Chemicals, Inc.
    Inventors: Atsushi Miyata, Tomoki Tsutsui, Nobuhito Koga, Shinsuke Matsumoto, Kazuhiko Ohkubo
  • Publication number: 20100130631
    Abstract: Polyester polyol compositions have a low viscosity and are suited for the production of rigid polyurethane foams. Compositions for rigid polyurethane foams contain the polyester polyol compositions. Rigid polyurethane foams are produced therefrom. A polyester polyol composition is obtained by: a step (I) in which a dibasic acid compound (A) is reacted with a trihydric or higher polyhydric alcohol (a compound (B)); and a step (II) in which the reaction mixture from the step (I) is reacted with a hydroxycarboxylic acid compound (C); at least one compound (C) being a compound (C?) selected from the group consisting of ricinoleic acid compounds and 12-hydroxystearic acid compounds; the polyester polyol composition having a hydroxyl value in the range of 250 to 550 mg KOH/g and an average functionality of 3 to 8.
    Type: Application
    Filed: April 21, 2008
    Publication date: May 27, 2010
    Inventors: Atsushi MIYATA, Tomoki TSUTSUI, Nobuhito KOGA, Masahiro SASAKI, Shinsuke MATSUMOTO, Kazuhiko OHKUBO
  • Publication number: 20100029799
    Abstract: Highly-functionalized, low-viscosity polyether polyols are obtained by dehydration condensation reaction of alcohols. The polyether polyols are obtained by dehydration condensation of glycerin and monohydric and/or dihydric alcohol with the glycerin percentage being more than 50 mol % relative to 100 mol % of the total of the glycerin and alcohol. The glycerin may be crude glycerin obtained by hydrolysis or alcoholysis of natural fat and oils.
    Type: Application
    Filed: October 25, 2007
    Publication date: February 4, 2010
    Inventors: Atsushi Miyata, Tomoki Tsutsui, Nobuhito Koga, Shinsuke Matsumoto, Kazuhiko Ohkubo
  • Patent number: 5514748
    Abstract: A molding resin composition comprising 99.9 to 50% by weight of polyimide represented by the formula: ##STR1## and 0.1 to 50% by weight of polyether ketone resin and/or polyester resin, and more particularly comprising the polyester resin capable of forming an anisotropical molten phase at a temperature of 420.degree. C. or less, and a polyimide-based molding resin composition which comprises the said resins and other additives such as phenolic resin, fluororesin, graphite, carbon fibers, aromatic polyamide fibers, potassium titanate fibers and a crystallization accelerator, and is excellent in thermal resistance, chemical resistance, mechanical strength and processability.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: May 7, 1996
    Assignee: Mitsui Toatsu Chemicals, Inc.
    Inventors: Toshihiko Isutsumi, Toshiyuki Nakakura, Shuichi Morikawa, Katsunori Shimamura, Toshiaki Takahashi, Atsushi Morita, Nobuhito Koga, Akihiro Yamaguchi, Masahiro Ohta, Yoshihisa Gotoh, Masaki Amano, Hiroyasu Oochi, Kayako Ito
  • Patent number: 5321096
    Abstract: A thermoplastic resin composition comprise 99.9.about.50 parts by weight of one or more thermoplastic resin selected from the group consisting of aromatic polyimide, aromatic polyetherimide, aromatic polyamideimide, aromatic polyethersulfone and aromatic polyether ketone and 0.1.about.50 parts by weight of one or more liquid crystal type aromatic polyimide having recurring structural units represented by the formula (1): ##STR1## wherein R.sub.1 .about.R.sub.5 is a hydrogen atom, fluorine atom, trifluoromethyl, methyl, ethyl or cyano and may be the same or different, and R is a tetravalent radical having 6.about.27 carbon atoms and being selected from the group consisting of a monoaromatic radical, condensed polyaromatic radical and noncondensed aromatic radical connected each other with a direct bond or a bridge member.
    Type: Grant
    Filed: March 22, 1993
    Date of Patent: June 14, 1994
    Assignee: Mitsui Toatsu Chemical, Incorporated
    Inventors: Yuichi Okawa, Nobuhito Koga, Hideaki Oikawa, Tadashi Asanuma, Akihiro Yamaguchi
  • Patent number: 5312866
    Abstract: A molding resin composition comprising 99.9 to 50% by weight of polyimide represented by the formula: ##STR1## and 0.1 to 50% by weight of polyether ketone resin and/or polyester resin, and more particularly comprising the polyester resin capable of forming an anisotropical molten phase at a temperature of 420.degree. C. or less, and a polyimide-based molding resin composition which comprises the said resins and other additives such as phenolic resin, fluororesin, graphite, carbon fibers, aromatic polyamide fibers, potassium titanate fibers and a crystallization accelerator, and is excellent in thermal resistance, chemical resistance, mechanical strength and processability.
    Type: Grant
    Filed: May 14, 1992
    Date of Patent: May 17, 1994
    Assignee: Mitsui Toatsu Chemicals, Incorporated
    Inventors: Toshihiko Tsutsumi, Toshiyuki Nakakura, Shuichi Morikawa, Katsunori Shimamura, Toshiaki Takahashi, Atsushi Morita, Nobuhito Koga, Akihiro Yamaguchi, Masahiro Ohta, Yoshihisa Gotoh, Masaki Amano, Hiroyasu Oochi, Kayako Ito
  • Patent number: 5286840
    Abstract: A thermally stable polyimide which is blocked at the polymer terminal with a dicarboxylic acid anhydride represented by the formula (III): ##STR1## wherein Z is a divalent radical selected from the group consisting of a monoaromatic radical which is substantially unsubstituted or substituted with a radical having no reactivity with amine or dicarboxylic acid anhydride and has from 6 to 15 carbon atoms, a condensed polyaromatic radical or a noncondensed aromatic radical connected each other with a direct bond or a bridge member, and has a fundamental skeleton represented by recurring structural units of the formula (IV): ##STR2## and a process of preparing the polyimide.
    Type: Grant
    Filed: November 21, 1991
    Date of Patent: February 15, 1994
    Assignee: Mitsui Toatsu Chemicals, Inc.
    Inventors: Hideaki Oikawa, Nobuhito Koga, Akihiro Yamaguchi, Shoji Tamai
  • Patent number: 5206340
    Abstract: Integrated circuit sockets for use in a burn-in test are disclosed. The IC sockets are produced by injection molding of a specific polyimide having an inherent viscosity of 0.35 to 0.65 dl/g and essentially consisting of recurring units represented by the formula (I): ##STR1## wherein X is a radical selected from the group consisting of a bond, divalent hydrocarbon having from 1 to 10 carbon atoms, etc. and R is a tetravalent radical selected from the group consisting of an aliphatic radical having two or more carbon atoms, cycloaliphatic radical, monoaromatic radical etc.
    Type: Grant
    Filed: December 19, 1989
    Date of Patent: April 27, 1993
    Assignee: Mitsui Toatsu Chemicals, Inc.
    Inventors: Toshihiko Tsutsumi, Toshiyuki Nakakura, Taizo Nagahiro, Shuithi Morikawa, Nobuhito Koga
  • Patent number: 5087644
    Abstract: Provided are carbon-fiber-reinforced polyimide resin compositions having excellent mechanical strength. The compositions are formed of (a) 5-50 parts by weight of carbon fibers, which have been obtained by coating starting carbon fibers at surfaces thereof with an aromatic polysulfone resin and then heating the thus-coated carbon fibers at 300.degree.-400.degree. C., and (b) 95-50 parts by weight of a polyimide resin which perferably have recurring units of following formula: ##STR1## wherein X represents a specific divalent radical and R represents a particular tetra-valent radical.
    Type: Grant
    Filed: February 15, 1990
    Date of Patent: February 11, 1992
    Assignee: Mitsui Toatsu Chemicals, Inc.
    Inventors: Toshihiko Tsutsumi, Toshiyuki Nakakura, Shuichi Morikawa, Nobuhito Koga
  • Patent number: 4960852
    Abstract: Thermosetting resin compositions are provided which comprise aromatic bismaleimide derivatives, for example, 2,2-bis[4(3-maleimidephenoxy)phenyl]propane and diamine derivatives, for example, 4,4'-bis(3-aminophenoxy)biphenyl. Prepolymers are also prepared by conducting heat-treatment of said compositions. The compositions of this invention are used for thermoforming such as compression molding etc. as well as raw materials of adhesives and coatings. The compositions provide molded articles which are excellent, for example, impact strength, flexibility and high-temperature stability.
    Type: Grant
    Filed: February 1, 1989
    Date of Patent: October 2, 1990
    Assignee: Mitsui Toatsu Chemicals, Inc.
    Inventors: Norimasa Yamaya, Nobuhito Koga, Masahiro Ohta, Akihiro Yamaguchi
  • Patent number: 4908409
    Abstract: Polyimide of this invention is almost colorless and has remarkably high light transmittance as well as excellent processability and adhesive properties at high temperatures in addition to its substantial high-temperature stability.The polyimide is a novel polyimide capable of being used for space and aeronautical materials, electric and electronic members, automotive parts, and furthermore for high-temperature adhesives.The polyimide has recurring units of the following formula ##STR1## wherein X is a radical selected from the group consisting of a bond, divalent hydrocarbon radical having from 1 to 10 carbons, hexafluorinated isopropylidene radical, carbonyl radical, sulfonyl radical and thio radical, and each nitrogen atom of imide ring is located simultaneously at meta- or para-position to ether linkage.
    Type: Grant
    Filed: November 10, 1987
    Date of Patent: March 13, 1990
    Assignee: Mitsui Toatsu Chemicals, Inc.
    Inventors: Hideaki Oikawa, Katsuaki Liyama, Nobuhito Koga, Saburo Kawashima, Shoji Tamai, Masahiro Ohta, Akihiro Yamaguchi
  • Patent number: 4847311
    Abstract: This invention is a polyimide resin composition containing 100 parts by weight of polyimide having recurring units of the following general formula (I): ##STR1## where Y is a bond, divalent hydrocarbon radical having from 1 to 10 carbons, hexafluorinated isopropylidene radical, carbonyl radical, thio radical, sulfinyl radical, sulfonyl radical or oxide, and R is a tetra-valent radical of aliphatic radical having 2 or more carbons, cyclic aliphatic radical, monocyclic aromatic radical, fused polycyclic radical and polycyclic aromatic radical wherein the aromatic radicals are linked to one another directly or via bridged member, and from 5 to 100 parts by weight of fibrous reinforcing materials such as glass fibres, carbon fibres, potassium titanate fibres and aromatic polyamide fibres.
    Type: Grant
    Filed: November 30, 1987
    Date of Patent: July 11, 1989
    Assignee: Mitsui Toatsu Chemicals, Inc.
    Inventors: Norimasa Yamaya, Nobuhito Koga, Kenichi Baba
  • Patent number: 4831102
    Abstract: Thermosetting resin compositions are provided which comprise aromatic bismaleimide derivatives, for example, 2,2-bis[4(3-maleimidephenoxy)phenyl]propane and diamine derivatives, for example, 4,4'-bis(3-aminophenoxy)biphenyl. Prepolymers are also prepared by conducting heat-treatment of said compositions. The compositions of this invention are used for thermoforming such as compression molding etc. as well as raw materials of adhesives and coatings. The compositions provide molded articles which are excellent, for example, in impact strength, flexibility and high-temperature stability.
    Type: Grant
    Filed: July 8, 1987
    Date of Patent: May 16, 1989
    Assignee: Mitsui Toatsu Chemicals, Incorporated
    Inventors: Norimasa Yamaya, Nobuhito Koga, Masahiro Ohta, Akihiro Yamaguchi
  • Patent number: 4816516
    Abstract: This invention is a polyimide resin composition containing 100 parts by weight of polyimide having recurring units of the following formula: ##STR1## wherein Y is a bond, divalent hydrocarbon radical having from 1 to 10 carbons, hexafluorinated isopropylidene radical, carbonyl radical, thio radical, sulfinyl radical, sulfonyl radical or oxide, and R is a tetravalent radical of aliphatic radical having at least 2 carbons, alicyclic radical, monoaromatic radical, condensed polyaromatic radical, or noncondensed polyaromatic radical wherein aromatic radicals are mutually connected with a bond or a crosslinking function and from 5 to 100 parts by weight of fluororesin. The resin composition can provide molded products which are excellent in high-temperature stability, dimensional stability and mechanical strength and moreover have a low friction coefficient and good wear resistance. Therefore, the composition is useful as the material for electric and electronic devices, precision instrument parts etc.
    Type: Grant
    Filed: June 19, 1987
    Date of Patent: March 28, 1989
    Assignee: Mitsui Toatsu Chemicals, Inc.
    Inventors: Norimasa Yamaya, Nobuhito Koga, Kenichi Baba
  • Patent number: 4506042
    Abstract: Disclosed is a curable resin composition comprising (a) at least one maleimide compound selected from the group consisting of N-(alkenylphenyl)maleimide derivatives, and dimers and polymers thereof and (b) one or more kinds of epoxy resins, each having at least one epoxy group in the unit molecule thereof. The resin composition may contain, besides the above two components, an amino compound as a further component (c). The resin composition may comprise a prepolymer of any two components among the three components (a), (b) and (c) and the remaining component. The resin compositions are useful as molding materials, for the fabrication of laminates, and as varnishes, including insulation varnishes and impregnating varnishes.
    Type: Grant
    Filed: April 4, 1983
    Date of Patent: March 19, 1985
    Assignee: Mitsui Toatsu Chemicals, Inc.
    Inventors: Hikotada Tsuboi, Motoo Kawamata, Masayuki Oba, Nobuhito Koga
  • Patent number: 4500719
    Abstract: Disclosed are novel alkenylphenylmaleimide derivatives having the general formula ##STR1## where R is an alkenyl radical of from 3 to 12 carbon atoms, R' is a hydrogen atom, a halogen atom, or a straight-chain or branched alkyl radical of from 1 to 4 carbon atoms, and n is a whole number of from 1 to 4, and linear dimers thereof as well as a process for the preparation of such maleimide compounds.
    Type: Grant
    Filed: August 13, 1982
    Date of Patent: February 19, 1985
    Assignee: Mitsui Toatsu Chemicals, Incorporated
    Inventors: Masayuki Oba, Motoo Kawamata, Hikotada Tsuboi, Nobuhito Koga
  • Patent number: 4401777
    Abstract: Disclosed is a curable resin composition comprising (a) at least one maleimide compound selected from the group consisting of N-(alkenylphenyl)maleimide derivatives, and dimers and polymers thereof and (b) one or more kinds of epoxy resins, each having at least one epoxy group in the unit molecule thereof. The resin composition may contain, besides the above two components, an amino compound as a further component (c). The resin composition may comprise a prepolymer of any two components among the three components (a), (b) and (c) and the remaining component. The resin compositions are useful as molding materials, for the fabrication of laminates, and as varnishes, including insulation varnishes and impregnating varnishes.
    Type: Grant
    Filed: October 20, 1981
    Date of Patent: August 30, 1983
    Assignee: Mitsui Toatsu Chemicals, Inc.
    Inventors: Hikotada Tsuboi, Motoo Kawamata, Masayuki Oba, Nobuhito Koga
  • Patent number: 4400521
    Abstract: Maleimide compounds represented by the general formula (I) ##STR1## where R and R' are a hydrogen atom, a halogen atom, or an alkyl radical of from 1 to 4 carbon atoms, and n and n' are a whole number of from 1 to 4; and a process for the preparation of the maleimide compounds, in which a maleamic acid represented by the general formula (II) ##STR2## where R and R' are a hydrogen atom, a halogen atom, or an alkyl radical of from 1 to 4 carbon atoms, and n and n' are a whole number of from 1 to 4, is contacted with a dehydrating agent in an organic solvent.
    Type: Grant
    Filed: October 29, 1980
    Date of Patent: August 23, 1983
    Assignee: Mitsui Toatsu Chemicals, Incorporated
    Inventors: Masayuki Oba, Motoo Kawamata, Hikotada Tsuboi, Nobuhito Koga
  • Patent number: 4376206
    Abstract: Disclosed are novel alkenylphenylmaleimide derivatives having the general formula ##STR1## where R is an alkenyl radical of from 3 to 12 carbon atoms, R' is a hydrogen atom, a halogen atom, or a straight-chain or branched alkyl radical of from 1 to 4 carbon atoms, and n is a whole number of from 1 to 4, and linear dimers thereof as well as a process for the preparation of such maleimide compounds.
    Type: Grant
    Filed: March 19, 1980
    Date of Patent: March 8, 1983
    Assignee: Mitsui Toatsu Chemicals, Inc.
    Inventors: Masayuki Oba, Motoo Kawamata, Hikotada Tsuboi, Nobuhito Koga
  • Patent number: 4323662
    Abstract: Disclosed is a thermosetting resin composition comprising (a) a bismaleimide and/or a polymaleimide and (b) at least one member selected from alkenylaniline derivatives, linear dimers thereof, and polymers thereof. In addition to components (a) and (b), this resin composition can contain (c) a polymerizable unsaturated substance.
    Type: Grant
    Filed: July 8, 1980
    Date of Patent: April 6, 1982
    Assignee: Mitsui Toatsu Chemicals, Inc.
    Inventors: Masayuki Oba, Motoo Kawamata, Hikotada Tsuboi, Nobuhito Koga