Patents by Inventor Hikotada Tsuboi

Hikotada Tsuboi 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: 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: 4440920
    Abstract: Aromatic polyesters are obtained by copolycondensing isophthalic acid and terephthalic acid or derivatives thereof with bis(hydroxyphenyl) sulfone and 2,2-bis(4'-hydroxyphenyl)propane.These aromatic polyesters have excellent molding workability. From these polyesters, colorless, transparent moldings can be obtained by compression, extrusion or injection molding methods. The products thus obtained have excellent mechanical and electrical properties and improved heat resistance.
    Type: Grant
    Filed: December 10, 1982
    Date of Patent: April 3, 1984
    Assignee: Mitsui Toatsu Chemicals, Inc.
    Inventors: Shiro Fujikake, Motoo Kawamata, Hikotada Tsuboi
  • 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
  • Patent number: 4289699
    Abstract: N-(hydroxyphenyl) maleimides of the general formula ##STR1## where R' stands for H, CH.sub.3, C.sub.2 H.sub.5, F, Cl, Br or I and n is an integer of 1-5 are produced by treating the corresponding maleamic acid or by treating the ester of said N-(hydroxyphenyl) maleimide at a temperature of 0.degree.-150.degree. C. in the presence of at least one dehydrating agent selected for the group consisting of oxides and oxyacids of sulfur or phosphorus and alkali metal and alkaline earth metal salts of the said oxyacids. The corresponding maleamic acid can be obtained by reacting an aminophenol having one or more hydroxyl groups on its phenyl nucleus with maleic anhydride. The esters of the N-(hydroxyphenyl maleimide) can be obtained by reacting said aminophenol and said maleic anhydride in the presence of a conventional acid anhydride dehydrating agent and a conventional imide-forming cyclization catalyst.
    Type: Grant
    Filed: October 26, 1979
    Date of Patent: September 15, 1981
    Assignee: Mitsui Toatsu Chemicals, Incorporated
    Inventors: Masayuki Oba, Motoo Kawamata, Hikotada Tsuboi, Nobuhito Koga
  • Patent number: 4231934
    Abstract: N-(hydroxyphenyl) maleimides of the general formula ##STR1## where R' stands for H, CH.sub.3, C.sub.2 H.sub.5, F, Cl, Br or I and n is an integer of 1-5 are produced by treating the corresponding maleamic acid or by treating the ester of said N-(hydroxyphenyl) maleimide at a temperature of 0-150.degree. C. in the presence of at least one dehydrating agent selected from the group consisting of oxides and oxyacids of sulfur or phosphorus and alkali metal and alkaline earth metal salts of the said oxyacids. The corresponding maleamic acid can be obtained by reacting an aminophenol having one or more hydroxyl groups on its phenyl nucleus with maleic anhydride. The esters of the N-(hydroxyphenyl maleimide) can be obtained by reacting said aminophenol and said maleic anhydride in the presence of a conventional acid anhydride dehydrating agent and a conventional imide-forming cyclization catalyst.
    Type: Grant
    Filed: November 2, 1978
    Date of Patent: November 4, 1980
    Assignee: Mitsui Toatsu Chemicals, Incorporated
    Inventors: Masayuki Oba, Motoo Kawamata, Hikotada Tsuboi, Nobuhito Koga