Patents by Inventor Mituhiro Ohta

Mituhiro Ohta 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: 5488101
    Abstract: Herein is provided a trisazo compound represented by formula (I) in the free acid form: ##STR1## wherein Q.sub.1 is an unsubstituted or substituted phenylene or naphthylene group, Q.sub.2 is an unsubstituted or substituted phenyl or naphthyl group, Z is --SO.sub.2 CH.sub.2 CH.sub.2 OH or --SO.sub.2 CH.sub.2 CH.sub.2 SO.sub.3 H group, and L is 0 or 1. The trisazo compound provided herein is excellent in solubility and gives deep colored dyed product or image when used in dyeing or printing, so that it is useful as a dye and an ink. Herein are also provided a method for dyeing fiber materials, paper or leather by using said trisazo compound, and an ink containing said trisazo compound.
    Type: Grant
    Filed: June 5, 1992
    Date of Patent: January 30, 1996
    Assignee: Sumitomo Chemical Company, Limited
    Inventors: Kazuya Ogino, Kingo Akahori, Naoki Harada, Yutaka Kayane, Hideo Kawashita, Mituhiro Ohta
  • Patent number: 5183501
    Abstract: An ink composition for ink jet recording, which contains a water-soluble dye, an organic solvent and water, in which the dye is represented by the formula (1) as shown in the state of free acid:D--(SO.sub.2 CH.sub.2 CH.sub.2 SO.sub.3 H).sub.m (1)wherein D represents a dye residue selected from the group of monoazo and polyazo dyes, their complexes with Cr, Fe, Co and Cu, copper and nickel phthalocyanine dyes, anthraquinone dyes, dioxazine dyes, and formazane complex dyes, and m represents an integer of 1, 2, 3 or 4, and which is superior in its stability during preservation and while being used, thermal stability, image clearness, water resistivity, light fastness, etc.
    Type: Grant
    Filed: October 11, 1991
    Date of Patent: February 2, 1993
    Assignees: Sumitomo Chemical Company, Limited, Taoka Chemical Co. Ltd.
    Inventors: Hideo Kawashita, Mituhiro Ohta, Kazuya Ogino
  • Patent number: 5149366
    Abstract: A disazo compound of the formula (I) in the free acid form, ##STR1## and an ink jet recording ink composition containing the same are provided, and the composition is superior in stability during storage or use, heat resistance, image clearness, water resistance and light fastness, and has a desirable tint as a red color.
    Type: Grant
    Filed: October 9, 1991
    Date of Patent: September 22, 1992
    Assignees: Sumitomo Chemical Company, Limited, Taoka Chemical Company
    Inventors: Hideo Kawashita, Mituhiro Ohta, Kazuya Ogino