Patents by Inventor Asim K. Sarkar

Asim K. Sarkar 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).

  • Low color, low sodium benzoxazinone UV absorbers and process for making same
    Patent number: 6774232
    Abstract: The present invention relates to benzoxazinone compounds having a yellow index less than about 0, and a sodium concentration less than about 50 ppm. This invention also relates to a process for preparing these compounds comprising the step of reacting an isatoic anhydride with approximately stoichiometric amounts of an acylating compound, where the isatoic anhydride is purified by re-crystallization or other purification methods.
    Type: Grant
    Filed: July 31, 2002
    Date of Patent: August 10, 2004
    Assignee: Cytec Technology Corp.
    Inventor: Asim K. Sarkar
  • Low color, low sodium benzoxazinone UV absorbers and process for making same
    Publication number: 20030096889
    Abstract: The present invention relates to benzoxazinone compounds having a yellow index less than about 0, and a sodium concentration less than about 50 ppm. This invention also relates to a process for preparing these compounds comprising the step of reacting an isatoic anhydride with approximately stoichiometric amounts of an acylating compound, where the isatoic anhydride is purified by re-crystallization or other purification methods.
    Type: Application
    Filed: July 31, 2002
    Publication date: May 22, 2003
    Inventor: Asim K. Sarkar