Patents by Inventor Tadashi Ohkuma

Tadashi Ohkuma 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).

  • Acrylic ester compound usage thereof
    Patent number: 6794471
    Abstract: An acrylic ester compound represented by the general formula (1): wherein, R1 and R2 represent independently a hydrogen atom, an alkyl group which may have a substituent, an aromatic alkyl group which may have a substituent or an aromatic residue which may have a substituent, respectively; R3 represents a hydrogen atom or an alkyl group; A represents a divalent organic group; and X represents a sulfur atom or an oxygen atom; provided that when X is an oxygen atom, R1 represents an aromatic residue that may have a substituent, a polymerizable composition comprising the compound, and a cured article and optical components obtained by polymerizing the polymerizable composition.
    Type: Grant
    Filed: September 24, 2001
    Date of Patent: September 21, 2004
    Assignee: Mitsui Chemicals, Inc.
    Inventors: Tadashi Ohkuma, Masao Imai, Mitsuo Nakamura, Atsuo Otsuji
  • Sulfur-containing unsaturated carboxylate compound and its cured products
    Patent number: 6458908
    Abstract: A sulfur-containing unsaturated carboxylate compound comprising a sulfur-containing substituent and at least two &agr;,&bgr;-unsaturated carboxylic acid residues, which are each attached to a secondary or tertiary carbon atom via an oxygen atom; a polymerizable composition comprising the sulfur-containing unsaturated carboxylate compound; a cured product prepared by polymerizing the polymerizable composition; an optical component consisting of the cured product; and novel intermediate compounds for preparation of the above carboxylate.
    Type: Grant
    Filed: May 31, 2000
    Date of Patent: October 1, 2002
    Assignee: Mitsui Chemicals, Inc.
    Inventors: Masao Imai, Kenichi Sugimoto, Kenichi Fujii, Atsuo Otsuji, Tadashi Ohkuma, Masatoshi Takagi, Rihoko Suzuki, Keisuke Takuma
  • Acrylic ester compound and usage thereof
    Publication number: 20020061995
    Abstract: An acrylic ester compound represented by the general formula (1): 1
    Type: Application
    Filed: September 24, 2001
    Publication date: May 23, 2002
    Inventors: Tadashi Ohkuma, Masao Imai, Mitsuo Nakamura, Atsuo Otsuji