Patents Assigned to Sojitz Corporation
  • Solvent-soluble 6,6-polyimide copolymers and processes for preparing them
    Patent number: 8742031
    Abstract: Heat-resistant polyimide copolymers having the following four components: pyromellitic dianhydride (PMDA), 1,4-diaminodiphenyl ether (DADE), biphenyltetracarboxylic dianhydride (BPDA), and 2,4-diaminotoluene (DAT) are provided. In an embodiment the molar ratio of (BPDA):(DADE):(PMDA):(DAT) is 2:2:m:m, in which m is an integer of 3, 4 or 5.
    Type: Grant
    Filed: April 3, 2007
    Date of Patent: June 3, 2014
    Assignees: Solpit Industries, Ltd., Sojitz Corporation
    Inventor: Hiroshi Itatani
  • Solvent-Soluble 6,6-Polyimide Copolymers and Processes for Preparing Them
    Publication number: 20130018167
    Abstract: Heat-resistant polyimide copolymers having the following four components: pyromellitic dianhydride (PMDA), 1,4-diaminodiphenyl ether (DADE), biphenyltetracarboxylic dianhydride (BPDA), and 2,4-diaminotoluene (DAT) are provided. In an embodiment the molar ratio of (BPDA):(DADE):(PMDA):(DAT) is 2:2:m:m, in which m is an integer of 3, 4 or 5.
    Type: Application
    Filed: April 3, 2007
    Publication date: January 17, 2013
    Applicants: SOJITZ CORPORATION, SOLPIT INDUSTRIES, LTD.
    Inventor: Hiroshi Itatani
  • 6,6-polyimide copolymers and processes for preparing them
    Patent number: 8349971
    Abstract: The present invention provides a process for preparing a solvent-soluble polyimide copolymer synthesized from a 6,6-imide segment having an imide oligomer with PMDA at both ends produced by adding 4 molar equivalents of pyromellitic dianhydride (PMDA) and 2 molar equivalents of diaminotoluene (DAT) to an imide oligomer produced by heating 1 molar equivalent of biphenyltetracarboxylic dianhydride (BPDA) and 2 molar equivalents of diaminodiphenyl ether (DADE) at 160-200° C. in the presence of a catalyst in an organic polar solvent.
    Type: Grant
    Filed: June 18, 2007
    Date of Patent: January 8, 2013
    Assignees: Solpit Industries, Ltd., Sojitz Corporation
    Inventor: Hiroshi Itatani
  • 6,6-Polyimide Copolymers and Processes for Preparing Them
    Publication number: 20100273955
    Abstract: The present invention provides a process for preparing a solvent-soluble polyimide copolymer synthesized from a 6,6-imide segment having an imide oligomer with PMDA at both ends produced by adding 4 molar equivalents of pyromellitic dianhydride (PMDA) and 2 molar equivalents of diaminotoluene (DAT) to an imide oligomer produced by heating 1 molar equivalent of biphenyltetracarboxylic dianhydride (BPDA) and 2 molar equivalents of diaminodiphenyl ether (DADE) at 160-200° C. in the presence of a catalyst in an organic polar solvent.
    Type: Application
    Filed: June 18, 2007
    Publication date: October 28, 2010
    Applicants: SOLPIT INDUSTRIES, LTD., SOJITZ CORPORATION
    Inventor: Hiroshi Itatani