Patents by Inventor Toshitake Yamakawa

Toshitake Yamakawa 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).

  • S,S-ethylenediamine-N,N?-disuccinic acid iron alkali salt and a process for production thereof
    Patent number: 6515159
    Abstract: An S,S-ethylenediamine-N,N′-disuccinic acid iron alkali salt which contains a lactam compound represented by the following general formula (1): wherein M is an ammonium ion or an alkali metal ion, and an ethylenediaminemonosuccinic acid represented by the following general formula (2): wherein M is an ammonium ion or an alkali metal ion, in an amount of 7 wt % or less, respectively.
    Type: Grant
    Filed: August 17, 2001
    Date of Patent: February 4, 2003
    Assignee: Mitsubishi Rayon Co., Ltd.
    Inventors: Toshitake Yamakawa, Haruo Sakai
  • S, S-ethylenediamine-N, N'-disuccinic acid iron alkali salt and a process for production thereof
    Publication number: 20020040156
    Abstract: An S,S-ethylenediamine-N,N′-disuccinic acid iron alkali salt which contains a lactam compound represented by the following general formula (1): 1
    Type: Application
    Filed: August 17, 2001
    Publication date: April 4, 2002
    Applicant: Mitsubishi Rayon Co., Ltd.
    Inventors: Toshitake Yamakawa, Haruo Sakai
  • Iron alkali salt of S,S-ethylenediamine-N,N?-disuccinic acid and process for producing the same
    Patent number: 6300510
    Abstract: An S,S-ethylenediamine-N,N′-disuccinic acid iron alkali salt which contains a lactam compound represented by the following general formula (1): wherein M is an ammonium ion or an alkali metal ion, and an ethylenediaminemonosuccinic acid represented by the following general formula (2): wherein M is an ammonium ion or an alkali metal ion, in an amount of 7 wt % or less, respectively.
    Type: Grant
    Filed: April 28, 2000
    Date of Patent: October 9, 2001
    Assignee: Mitsubishi Rayon Co., Ltd.
    Inventors: Toshitake Yamakawa, Haruo Sakai
  • Alkylenediamine-N,N'-disuccinic acid iron (III) complex salts and process for production thereof
    Patent number: 5679817
    Abstract: (S,S)-ethylenediamine-N,N'-disuccinic acid iron (III) ammonium salt represented by the formula: ##STR1## wherein C* is an asymmetric carbon atom. This compound has a very high biodegradability and it is not accumulated in the environment even when used as a photographic processing agent or the like. Therefore, the compound is advantageous for the protection of environment.
    Type: Grant
    Filed: July 21, 1995
    Date of Patent: October 21, 1997
    Assignee: Nitto Chemical Industry Co., Ltd.
    Inventors: Haruo Sakai, Takashi Sato, Toshitake Yamakawa