Patents by Inventor Akiharu Fujita

Akiharu Fujita 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: 4609680
    Abstract: Polyethylene terephthalate scrap is depolymerized to bis-hydroxyethyl terephthalate and/or its oligomer (BHT) by supplying the scrap, together with ethylene glycol, to a reactor containing molten BHT under the following conditions(a) the molten BHT has a glycol to acid component equivalent ratio of 1.3 to 2.0(b) the ratio by weight of the acid component of the molten BHT to that of the polyester scrap is 1/4 to 2/1(c) the ratio of polyester scrap to ethylene glycol is such as to have a glycol to acid component equivalent ratio between the limits of 1.3 to 2.0.The depolymerization is performed at 215.degree. to 250.degree. C. with agitation of the reactants, after which a part of the product in the reactor be removed to a polymerizing reactor.
    Type: Grant
    Filed: May 20, 1985
    Date of Patent: September 2, 1986
    Assignee: Toray Industries, Inc.
    Inventors: Akiharu Fujita, Minako Sato, Masashige Murakami