Patents by Inventor Hideaki Oikawa

Hideaki Oikawa 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: 5322962
    Abstract: Disclosed are a novel aromatic diamine; a polymide comprising 1,3-bis(3-aminobenzoyl)benzene or 4,4'-bis(3-aminobenzoyl)biphenyl as a diamine component and having recurring structural units represented by the formula (III): ##STR1## wherein R is a tetravalent radical selected from the group consisting of an aliphatic radical having from 2 to 27 carbon atoms, alicyclic radical, monoaromatic radical, condensed polyaromatic radical, and noncondensed aromatic radical connected each other with a direct bond or a bridge member, and X is a divalent radical of ##STR2## and a polyimide having a terminal aromatic group which is essentially unsubstituted or substituted with a radical having no reactivity with amines or dicarboxylic acid anhydrides or a composition comprising said polyimide.
    Type: Grant
    Filed: May 12, 1993
    Date of Patent: June 21, 1994
    Assignee: Mitsui Toatsu Chemicals, Inc.
    Inventors: Shoji Tamai, Keizaburo Yamaguchi, Yuko Ishihara, Saburo Kawashima, Hideaki Oikawa, Toshiyuki Kataoka, Akihiro Yamaguchi
  • 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: 5288843
    Abstract: In one aspect, the present invention relates to polyimides having excellent thermal resistance and process for preparing the same comprising carrying out condensation of 4,4'-bis(3-aminophenoxy)biphenyl with pyromellitic dianhydride in the presence of a different diamine compound and optionally with a different tetracarboxylic acid dianhydride.In a second aspect, the present invention relates to a heat resistant resin composition consisting essentially of an aromatic polyetherimide and a defined polyimide.In a third aspect, the present invention relates to a polyimide resin composition comprised on a defined polyimide and a separate high-temperature engineering polymer.In a fourth aspect, the present invention relates to a resin composition comprised of a defined polyimide and an aromatic polyamideimide.
    Type: Grant
    Filed: November 5, 1990
    Date of Patent: February 22, 1994
    Assignee: Mitsui Toatsu Chemicals, Inc.
    Inventors: Shoji Tamai, Masahiro Ohta, Saburo Kawashima, Katsuaki Iiyama, Hideaki Oikawa, Akihiro Yamaguchi, Kouji Ohkoshi, Masao Yoshikawa
  • 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: 5278276
    Abstract: Polyimide having repeating units of the following formula (I) and its polyamic acid precursor having repeating units of the following formula (II) are disclosed; ##STR1## (where Y is a radical selected from the group consisting of a bond, divalent hydrocarbon having 1 to 10 carbons, hexafluorinated isopropylidene, carbonyl, thio, sulfinyl, sulfonyl and oxide, and R is a tetra-valent radical selected from the group consisting of aliphatic radical having 2 and more carbons, cyclo-aliphatic radical, monoaromatic radical, condensed polyaromatic radical, and non-condensed polyaromatic radical wherein aromatic radicals are mutually connected with a bond or a crosslinking function).Typical examples of polyimide and polyamic acid include where Y is thio radical and R is ##STR2## Y is a bond and R is III or IV, and Y is isopropylidene radical and R is IV.The polymers can be prepared from corresponding diamine and tetracarboxylic acid dianhydride.
    Type: Grant
    Filed: January 26, 1993
    Date of Patent: January 11, 1994
    Assignee: Mitsui Toatsu Chemicals, Incorporated
    Inventors: Masahiro Ohta, Saburo Kawashima, Yoshiho Sonobe, Shoji Tamai, Hideaki Oikawa, Kouji Ohkoshi, Akihiro Yamaguchi
  • Patent number: 5231160
    Abstract: A novel aromatic diamine; a polyimide comprising 1,3-bis(3-aminobenzoyl)benzene or 4,4'-bis(3-aminobenzoyl)biphenyl as a diamine component and having recurring structural units represented by the formula (III): ##STR1## wherein R is a tetravalent radical selected from the group consisting of an aliphatic radical having from 2 to 27 carbon atoms, alicyclic radical, monoaromatic radical, condensed polyaromatic radical, and noncondensed aromatic radical connected each other with a direct bond or a bridge member, and X is a divalent radical of ##STR2## and a polyimide having a terminal aromatic group which is essentially unsubstituted or substituted with a radical having no reactivity with amines or dicarboxylic acid anhydrides or a composition comprising said polyimide.
    Type: Grant
    Filed: August 29, 1991
    Date of Patent: July 27, 1993
    Assignee: Mitsui Toatsu Chemicals, Incorporated
    Inventors: Shoji Tamai, Keizaburo Yamaguchi, Yuko Ishihara, Saburo Kawashima, Hideaki Oikawa, Toshiyuki Kataoka, Akihiro Yamaguchi
  • Patent number: 5210174
    Abstract: In a process for the preparation of polyimide by reacting a diamine compound with tetracarboxylic dianhydride in a phenol based solvent, an improved process for reacting the diamine compound with tetracarboxylic dianhydride in a solution by forming separate solutions of the tetracarboxylic dianhydride and the diamine compound and mixing the solutions and/or by dissolving tetracarboxylic dianhydride in the phenol-based solvent containing an organic base.
    Type: Grant
    Filed: November 14, 1990
    Date of Patent: May 11, 1993
    Assignee: Mitsui Toatsu Chemicals, Inc.
    Inventors: Shoji Tamai, Hideaki Oikawa, Masahiro Ohta, Akihiro Yamaguchi
  • Patent number: 5205894
    Abstract: Polyimide having repeating units of the following formula (I) and its polyamic acid precursor having repeating units of the following formula (II) are disclosed; ##STR1## (where Y is a radical selected from the group consisting of a bond, divalent hydrocarbon having 1 to 10 carbons, hexafluorinated isopropylidene, carbonyl, thio, sulfinyl, sulfonyl and oxide, and R is a tetra-valent radical selected from the group consisting of aliphatic radical having 2 and more carbons, cyclo-aliphatic radical, monoaromatic radical, condensed polyaromatic radical, and non-condensed polyaromatic radical wherein aromatic radicals are mutually connected with a bond or a crosslinking function).Typical examples of polyimide and polyamic acid include where Y is thio radical and R is ##STR2## Y is a bond and R is III or IV, and Y is isopropylidene radical and R is IV.The polymers can be prepared from corresponding diamine and tetracarboxylic acid dianhydride.
    Type: Grant
    Filed: June 17, 1991
    Date of Patent: April 27, 1993
    Assignee: Mitsui Toatsu Chemicals, Inc.
    Inventors: Masahiro Ohta, Saburo Kawashima, Yoshiho Sonobe, Shoji Tamai, Hideaki Oikawa, Kouji Ohkoshi, Akihiro Yamaguchi
  • Patent number: 5157085
    Abstract: This invention relates to molding resin compositions, and more particularly relates to polyimide resin compositions having markedly improved molding ability in addition to excellent high temperature stability, chemical resistance and mechanical strength.The polyimide resin compositions of this invention comprises 99.9 to 50.0% by weight of the polyimide and 0.1 to 50.0% by weight of polyphenylene sulfide and/or aromatic polysulfone and/or aromatic polyetherimide high-temperature engineering polymer.
    Type: Grant
    Filed: March 9, 1989
    Date of Patent: October 20, 1992
    Assignee: Mitsui Toatsu Chemicals, Incorporated
    Inventors: Masahiro Ohta, Saburo Kawashima, Katsuaki Iiyama, Shoji Tamai, Hideaki Oikawa, Akihiro Yamaguchi
  • Patent number: 5087689
    Abstract: Polyimide having repeating units of the following formula (I) and its polyamic acid precursor having repeating units of the following formula (II) are disclosed; ##STR1## (where Y is a radical selected from the group consisting of a bond, divalent hydrocarbon having 1 to 10 carbons, hexafluorinated isopropylidene, carbonyl, thio, sulfinyl, sulfonyl and oxide, and R is a tetra-valent radical selected from the group consisting of aliphatic radical having 2 and more carbons, cyclo-aliphatic radical, monoaromatic radical, condensed polyaromatic radical, and noncondensed polyaromatic radical wherein aromatic radicals are mutually connected with a bond or a crosslinking function).Typical examples of polyimide and polyamic acid include where Y is thio radical and R is ##STR2## Y is a bond and R is III or IV, and Y is isopropylidene radical and R is IV.The polymers can be prepared from corresponding diamine and tetracarboxylic acid dianhydride.
    Type: Grant
    Filed: November 9, 1990
    Date of Patent: February 11, 1992
    Assignee: Mitsui Toatsu Chemicals, Inc.
    Inventors: Masahiro Ohta, Saburo Kawashima, Yoshiho Sonobe, Shoji Tamai, Hideaki Oikawa, Kouji Ohkoshi, Akihiro Yamaguchi
  • Patent number: 5086125
    Abstract: This invention relates to molding resin compositions, and more particularly relates to polyimide resin compositions having markedly improved molding ability in addition to excellent high temperature stability, chemical resistance and mechanical strength.The polyimide resin composition of this invention comprises 99.9 to 50% by weight of the polyimide and 0.1 to 50% by weight of high temperature engineering polymer. The polyimide has recurring units of the following formula: ##STR1## wherein X is a sulfonyl radical or a carbonyl radical and R is a tetravalent radical selected from an aliphatic radical, alicyclic radical, monoaromatic radical, condensed aromatic radical and non-condensed aromatic radical.
    Type: Grant
    Filed: August 24, 1990
    Date of Patent: February 4, 1992
    Assignee: Mitsui Toatsu Chemicals, Inc.
    Inventors: Masahiro Ohta, Saburo Kawashima, Katsuaki Iiyama, Shoji Tamai, Hideaki Oikawa, Akihiro Yamaguchi
  • Patent number: 5043419
    Abstract: This invention relates to a method for preparing a polyimide having good heat-stability and excellent flowability in a molten state.The polymide is prepared by reacting aromatic diamines such as 4,4'-bis(3-aminophenoxy)biphenyl, bis[4-(3-aminophenoxy)phenyl] ketone and bis [4-(3-aminophenoxy)phenyl] sulfone; tetracarboxylic dianhydrides such as pyromellitic dianhydride, 3,3', 4,4'-benzophenonetetracarboxylic dianhydride and bis(3,4-dicarboxyphenyl) ether dianhydride; and dicarboxylic anhydrides such as glutaric anhydride, 1,2-hexanedicarboxylic anhydride, phthalic anhydride and 3,4-benzophenonedicarboxylic anhydride. The molar ratio of aromatic diamine: tetracarboxylic dianhydride: dicarboxylic anhydride is 1:(0.9 to 1.0):(0.001 to 1.0).The invention also relates to polyimide composite materials which are excellent in mechanical strengths and processability.
    Type: Grant
    Filed: October 24, 1988
    Date of Patent: August 27, 1991
    Assignee: Mitsui Toatsu Chemicals, Inc.
    Inventors: Masahiro Ohta, Saburo Kawashima, Shoji Tamai, Hideaki Oikawa, Akihiro Yamaguchi, Tomohito Koba, Toshiyuki Nakakura, Hideo Sakai, Misao Masuda, Satoru Kishi, Chiaki Maruko
  • Patent number: 5041520
    Abstract: Disclosed is a process for preparing a polyimide by reacting certain reactants. The reactants include an aromatic diamine which is 3,3'-diaminobenzophenone and/or bis(3-aminophenyl)sulfone, a tetrocarboxylic dianhydride and a dicarboxylic anhydride. A thermally stable polyimide can be obtained which displays excellent processability.
    Type: Grant
    Filed: June 26, 1989
    Date of Patent: August 20, 1991
    Assignee: Mitsui Toatsu Chemicals, Inc.
    Inventors: Masahiro Ohta, Saburo Kawashima, Katsuaki Iiyama, Shoji Tamai, Hideaki Oikawa, Akihiro Yamaguchi
  • Patent number: 5013817
    Abstract: The invention relates to processes for preparing a polyimide, a polyimide composition prepared by the processes and polyimide composite materials containing the same.
    Type: Grant
    Filed: November 3, 1988
    Date of Patent: May 7, 1991
    Assignee: Mitsui Toatsu Chemicals, Inc.
    Inventors: Masahiro Ohta, Saburo Kawashima, Shoji Tamai, Hideaki Oikawa, Akihiro Yamaguchi, Tomohito Koba, Toshiyuki Nakakura, Hideo Sakai, Misao Masuda, Satoru Kishi, Chiaki Maruko
  • Patent number: 4987197
    Abstract: This invention relates to molding resin compositions, and more particularly relates to polyimide resin compositions having markedly improved molding ability in addition to excellent high temperature stability, chemical resistance and mechanical strength.The polyimide resin compositions of this invention comprises 99.9 to 50.0% by weight of the polyimide and 0.1 to 50.0% by weight of aromatic polyamideimide.
    Type: Grant
    Filed: April 24, 1989
    Date of Patent: January 22, 1991
    Assignee: Mitsui Toatsu Chemicals, Inc.
    Inventors: Masahiro Ohta, Saburo Kawashima, Katsuaki Iiyama, Shoji Tamai, Hideaki Oikawa, Akihiro Yamaguchi
  • Patent number: 4959440
    Abstract: This invention relates to a novel polyimide and describes method of its preparation, adhesives of the polyimide and the method for their application.The polyimide has recurring units of the formula ##STR1## (where the positions of two carbonyl radicals in a benzene ring are meta or para, and R is a tetra-valent radical selected from the group consisting of aliphatic radical having not less than two carbons, cyclo-aliphatic radical, monoaromatic radical, condensed polyaromatic radical, and non condensed polyaromatic radical wherein aromatic radicals are mutually connected with a bond or a crosslinking function).The polyimide can be prepared by reacting diamine with tetracarboxylic dianhydride in organic solvents and imidizing resultant polyamic acid.The diamine in use is ether diamine and includes 1,3-bis[4-(3-aminophenoxy)benzoyl]benzene and 1,4-bis[4-(3-aminophenoxy)benzoyl]benzene.
    Type: Grant
    Filed: January 23, 1987
    Date of Patent: September 25, 1990
    Assignee: Mitsui Toatsu Chemicals, Inc.
    Inventors: Shoji Tamai, Saburo Kawashima, Yoshiho Sonobe, Masahiro Ohta, Hideaki Oikawa, Akihiro Yamaguchi
  • Patent number: 4937316
    Abstract: A process for preparing a polyimide by reaction of a diamine and a tetracarboxylic dianhydride to obtain a polyamide acid and subjecting the polyamide acid to conversion into a polyimide thermally or chemically. The reaction in the process is carried out in the presence of at least one dicarboxylic anhydride selected from the group consisting of aliphatic dicarboxylic anhydrides and aromatic dicarboxylic anhydrides, and the amount of the tetracarboxylic dianhydride is in the range of from 0.9 to 1.0 mole per mole of the diamine and the amount of the dicarboxylic anhydride is in the range of from 0.001 to 1.0 mole per mole of the diamine. The resultant polyimides exhibit good thermal stability at high temperatures and good forming processability even at low temperatures.
    Type: Grant
    Filed: February 22, 1989
    Date of Patent: June 26, 1990
    Assignee: Amdahl Corporation
    Inventors: Masahiro Ohta, Saburo Kawashima, Katsuaki Iiyama, Shoji Tamai, Hideaki Oikawa, Akihiro Yamaguchi
  • Patent number: 4931531
    Abstract: This invention relates to a novel polyimide which is high-temperature resistant and capable of being molded in a fused state. This invention also relates to a high-temperature adhesive using the polyimide.The polyimide consists essentially of recurring units of the formula: ##STR1## where R is a tetra-valent radical selected from the group consisting of an aliphatic radical having 2 or more carbon atoms, alicyclic radical, monoaromatic radical, condensed polyaromatic radical, and non-condensed polyaromatic radical wherein aromatic radicals are linked to one another directly or via a bridge member.The polyimide can be prepared by reacting bis[4-(4-aminophenoxy)phenoxy)phenyl] sulfone with a tetracarboxylic dianhydride in an organic solvent and imidizing the resultant polyamic acid.
    Type: Grant
    Filed: June 24, 1988
    Date of Patent: June 5, 1990
    Assignee: Mitsui Toatsu Chemicals, Incorporated
    Inventors: Shoji Tamai, Masahiro Ohta, Saburo Kawashima, Katsuaki Iiyama, Hideaki Oikawa, 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: 4884911
    Abstract: A mechanical pencil comprising a tubular casing, a centrally apertured conical tip piece connected to an end of the tubular casing to form a pencil tip, a lead engaging chuck device longitudinally movably mounted within the tubular casing, first spring for biasing the chuck device rearwardly relative to the chuck actuator, second spring for biasing the chuck actuator longitudinally forwardly and circumferentially relative to the tubular casing, actuation knob device longitudinally mounted on the tubular casing for rotation the chuck actuator against a resilient force of the second spring, engagement device for slidably engaging the chuck actuator against a resilient force of the second spring, and locking device for locking the chuck actuator to prevent a further rotation of the chuck actuator to thereby release the engagement between the actuation knob and the chuck actuator.
    Type: Grant
    Filed: October 28, 1988
    Date of Patent: December 5, 1989
    Assignee: Pentel Kabushiki Kaisha
    Inventor: Hideaki Oikawa