Patents by Inventor Chizu Kawakami

Chizu Kawakami 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).

  • Optically active benzene derivatives, process for producing the same and liquid-crystalline composition containing said derivatives as liquid-crystalline compound and light switching elements
    Patent number: 5693251
    Abstract: An optically active phenol useful in the preparation of liquid crystalline compounds which is represented by the formula (V): ##STR1## wherein R.sub.2 represents an alkyl or alkoxyalkyl group having 1 to 20 carbon atoms optionally substituted by halogen atoms; Z' represents ##STR2## wherein q represents a number of 1 to 5 and * indicates asymmetric carbon atom; l represents a number of 2; t represents a number of 1 to 5; s represents a number of 0 or 1.
    Type: Grant
    Filed: November 23, 1994
    Date of Patent: December 2, 1997
    Assignee: Sumitomo Chemical Company, Limited
    Inventors: Takayuki Higashii, Isao Kurimoto, Shoji Toda, Masayoshi Minai, Takeshi Tani, Chizu Kawakami, Koichi Fujisawa
  • Optically active benzene derivatives, process for producing the same and liquid-crystalline composition containing said derivatives as liquid-crystalline compound and light switching elements
    Patent number: 5389293
    Abstract: Disclosed are herein optically active benzene derivatives represented by the formula (I): ##STR1## preparation processes therefor, liquid crystal composition containing such benzene derivatives as liquid-crystalline compound, and a light switching element using said liquid crystal composition as liquid crystal element, wherein R.sub.1, R.sub.2, x, y, z, m, p and s are as defined in the specification.
    Type: Grant
    Filed: July 9, 1992
    Date of Patent: February 14, 1995
    Assignee: Sumitomo Chemical Company, Limited
    Inventors: Takayuki Higashii, Isao Kurimoto, Shoji Toda, Masayoshi Minai, Takeshi Tani, Chizu Kawakami, Koichi Fujisawa
  • Optically active ester derivatives, preparation process thereof, liquid crystal materials and a light switching element
    Patent number: 5385693
    Abstract: Disclosed herein are optically active carboxylic acid or acid halide compounds of formula III: ##STR1## Wherein R.sub.2 represents an optically active alkyl or alkoxyalkyl group having 3 to 15 carbon atoms optionally substituted by halogen atoms; R' represents a hydroxyl group or a halogen atom; k is 0 or 1; and n represents an integer of 1 to 6.
    Type: Grant
    Filed: May 17, 1993
    Date of Patent: January 31, 1995
    Assignee: Sumitomo Chemical Company, Limited
    Inventors: Takayuki Higashii, Isao Kurimoto, Shoji Toda, Masayoshi Minai, Takeshi Tani, Chizu Kawakami, Koichi Fujisawa, Kiyoshi Imamura
  • Optically active ester derivatives, preparation process thereof, liquid crystal materials and a light switching element
    Patent number: 5264151
    Abstract: Disclosed herein are optically active phenols of formula (V) which are useful as precursors for esters used in liquid crystalline crystalline mixtures: ##STR1## wherein R.sub.2 represents an optically active alkyl or alkoxyalkyl group having 3 to 15 carbon atoms optionally substituted by halogen atoms; k represents a number of 0 or 1; n represents a number of 1 to 6.
    Type: Grant
    Filed: March 20, 1992
    Date of Patent: November 23, 1993
    Assignee: Sumitomo Chemical Company, Limited
    Inventors: Takayuki Higashi, Isao Kurimoto, Shoji Toda, Masayoshi Minai, Takeshi Tani, Chizu Kawakami, Koichi Fujisawa, Kiyoshi Imamura
  • Optically active ester derivatives, preparation process thereof, liquid crystal materials and a light switching element
    Patent number: 5124070
    Abstract: Disclosed are herein optically active ester derivatives represented by the formula (I): ##STR1## (wherein R.sub.1 represents an alkyl group having 3 to 20 carbon atoms; R.sub.2 represents an optically active alkyl or alkoxyalkyl group having 3 to 15 carbon atoms optionally substituted by halogen atoms; Y represents --O--, --COO-- or --OCO--; X represents --COO-- or --OCO--; l represents a number of 1 or 2; k and m each represents a number of 0 or 1; n represents a number of 1 to 6), preparation processes therefor, liquid crystal materials containing such ester derivatives as active ingredient, and a light switching element using said liquid crystal materials as liquid crystal element.
    Type: Grant
    Filed: August 28, 1989
    Date of Patent: June 23, 1992
    Assignee: Sumitomo Chemical Company, Limited
    Inventors: Takayuki Higashii, Isao Kurimoto, Shoji Toda, Masayoshi Minai, Takeshi Tani, Chizu Kawakami, Koichi Fujisawa, Kiyoshi Imamura