Patents by Inventor Norihiro Oiwa

Norihiro Oiwa 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).

  • Publication number: 20140020190
    Abstract: Methods for dyeing aramid fibers, and the dyed arimid fibers produced by these methods, which comprises a dye providing step in which a vat dye or a sulfur dye is provided to aramid fibers, a solvent treatment step in which the aramid fibers are treated by a treating solution containing a polar solvent, and after the solvent treatment step, a heat treatment step in which the aramid fibers are subjected to a heat treatment, if necessary, and having one or more dyeing operations comprising the combination of the respective steps dyeing operations. The dyeing methods can be applied to either of the para-type aramid fibers, the para-type copolymerized aramid fibers and the meta-type aramid fibers, which can be dyed to a practical color depth required for developing new applications of the aramid fibers. Colorfastness of the dyed product, in particular, colorfastness to light, is improved.
    Type: Application
    Filed: March 29, 2012
    Publication date: January 23, 2014
    Applicant: Tokai Senko K.K.
    Inventors: Norihiro Oiwa, Kazuki Imai, Shohei Sayama, Takahiro Ito, Akira Yasui