Patents by Inventor Yukio Muranaka

Yukio Muranaka 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: 6133406
    Abstract: The present invention relates to a process for preparing an aromatic polyamide which comprises:(A) a dicarboxylic acid component unit comprising 30 to 100 mol % of a terephthalic acid component unit, and, as required, 0 to 70 mol % of a cyclic dicarboxylic acid component unit other than the terephthalic acid and, as required, 0 to 15 mol % of an aliphatic dicarboxylic acid having 7 to 20 carbon atoms; and(B) a diamine unit comprising 50 to 100 mol % of a component unit derived from an aliphatic alkylene diamine having 4 to 25 carbon atoms, and 0 to 50 mol % of a component unit derived from an alicyclic diamine having 3 to 25 carbon atoms; said process comprising:a step (i) of preparing a solid low-degree condensation product having an intrinsic viscosity [.eta.].sub.1 of from 0.05 to 0.2 dl/g is prepared by the polycondensation reaction of the dicarboxylic acid with the diamine;a step (ii) of solid-phase polymerizing said low-degree condensation product at a temperature of not higher than 195.degree. C.
    Type: Grant
    Filed: November 18, 1998
    Date of Patent: October 17, 2000
    Assignee: Mitsui Chemicals, Inc.
    Inventors: Masaki Kosaka, Yukio Muranaka, Kenji Wakatsuru