Patents by Inventor Hajimu Kitahara

Hajimu Kitahara 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: 4963254
    Abstract: A packing material for chromatographic use wherein an organosilane of formula (I): ##STR1## wherein R.sub.1, R.sub.2 and R.sub.3, which may be the same or different, each represents an alkyl, alkoxy or hydroxyl group or a halogen atom, provided that at least one of them represents an alkoxy group or a halogen atom; X represents an --NHCO-- or --NH.sub.3.sup..+-. --OCO-- group; n is an integer of 2 to 4; and *C represents an asymmetric carbon atom, is grafted on an inorganic carrier having hydroxyl groups on the surface thereof as well as a method for the analysis of an enantiomer mixture using the same are disclosed.
    Type: Grant
    Filed: July 14, 1988
    Date of Patent: October 16, 1990
    Assignees: Sumitomo Chemical Company, Limited, Sumika Chemical Analysis Service
    Inventors: Naobumi Oi, Hajimu Kitahara, Tadashi Doi
  • Patent number: 4512898
    Abstract: A packing material for chromatographic use comprising an inorganic carrier having hydroxyl groups at the surface thereof having grafted thereon an organosilane derivative selected from the group consisting of a urea derivative obtained by reacting an optically active isocyanate with an aminoalkylsilane, an N-carbomoyl amino acid derivative obtained by reacting an optically active amino acid carbamoylated by isocyanate with an aminoalkylsilane and an O-carbamoyl hydroxy acid derivative obtained by reacting an optically active hydroxy acid carbamoylated by isocyanate with an aminoalkylsilane is disclosed. This packing material is useful as a packing material for liquid chromatography analysis which comprises separating and analyzing an enantiomer mixture of a compound having an --OH group, a --CONH-- group, ##STR1## a --COO-- group, an --NHCOO-- group, an --NHCONH-- group or ##STR2## bonded to an asymmetric carbon atom thereof.
    Type: Grant
    Filed: September 30, 1983
    Date of Patent: April 23, 1985
    Assignee: Sumitomo Chemical Company, Limited
    Inventors: Naobumi Oi, Hajimu Kitahara