Patents by Inventor Chinmoy Nandi

Chinmoy Nandi 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).

  • Process for preparing 4-aminodiphenylamine
    Patent number: 9708243
    Abstract: A process for preparing 4-aminodiphenylamine (4-ADPA) comprising steps of coupling of aniline with nitrobenzene in presence of a suitable base, e.g. tetramethylammonium hydroxide (TMAH), hydrogenation of the coupling mass, phase separation, hydrogenation of azobenzene in the separated organic mass and fractional distillation for 4-ADPA recovery. An improvement in 4-ADPA recovery and a lowering of tar formation are obtained due to azobenzene reduction prior to 4-ADPA isolation. Also a gain in volume productivity of 4-ADPA is obtained by suitably altering the batch cycle time of the coupling reaction.
    Type: Grant
    Filed: March 7, 2012
    Date of Patent: July 18, 2017
    Assignee: NOCIL LIMITED
    Inventors: Chinmoy Nandi, Narendra Gangal, Pramod Purohit, Vinay Ketkar, Dilip Kashelikar
  • Efficient continuous process for manufacturing of 4-aminodiphenylamine from aniline and nitrobenzene
    Patent number: 9102585
    Abstract: An efficient continuous manufacturing process for 4-aminodiphenylamine by coupling aniline with nitrobenzene in the presence of tetramethylammonium hydroxide (TMAH) as a base, using flow reactors wherein base decomposition is considerably reduced by optimizing base quantity, process conditions and process equipment.
    Type: Grant
    Filed: April 13, 2012
    Date of Patent: August 11, 2015
    Assignee: NOCIL LIMITED
    Inventors: Chinmoy Nandi, Narendra Gangal, Pramod Purohit, Vinay Ketkar, Prahlad Rao
  • PROCESS FOR PREPARING 4-AMINODIPHENYLAMINE
    Publication number: 20150045584
    Abstract: A process for preparing 4-aminodiphenylamine (4-ADPA) comprising steps of coupling of aniline with nitrobenzene in presence of a suitable base, e.g. tetramethylammonium hydroxide (TMAH), hydrogenation of the coupling mass, phase separation, hydrogenation of azobenzene in the separated organic mass and fractional distillation for 4-ADPA recovery. An improvement in 4-ADPA recovery and a lowering of tar formation are obtained due to azobenzene reduction prior to 4-ADPA isolation. Also a gain in volume productivity of 4-ADPA is obtained by suitably altering the batch cycle time of the coupling reaction.
    Type: Application
    Filed: March 7, 2012
    Publication date: February 12, 2015
    Applicant: NOCIL LIMITED
    Inventors: Chinmoy Nandi, Narendra Gangal, Pramod Purohit, Vinay Ketkar, Dilip Kashelikar
  • Efficient Continuous Process for Manufacturing of 4-Aminodiphenylamine From Aniline and Nitrobenzene
    Publication number: 20150038743
    Abstract: An efficient continuous manufacturing process for 4-aminodiphenylamine by coupling aniline with nitrobenzene in the presence of tetramethylammonium hydroxide (TMAH) as a base, using flow reactors wherein base decomposition is considerably reduced by optimizing base quantity, process conditions and process equipment.
    Type: Application
    Filed: April 13, 2012
    Publication date: February 5, 2015
    Applicant: NOCIL LIMITED
    Inventors: Chinmoy Nandi, Narendra Gangal, Pramod Purohit, Vinay Ketkar, Prahlad Rao
  • Sulfenamide accelerators for improved network stabilization of rubber vulcanizates
    Patent number: 8110634
    Abstract: Sulfenamide derivatives of 4-alkyl substituted 2-mercapto benzothiazole (4m-MBT) as accelerators used in vulcanizable rubber composition having improved ‘Reversion Resistance’ and ‘Modulus & Hardness Stabilization’ properties for sulphur vulcanized tire compounds predominantly based on Natural Rubber or its blends with Polybutadiene (BR) and styrene butadiene rubber (SBR) in which Natural Rubber is the major component thereby improving the overall tire performance, ride safety and tyre service life.
    Type: Grant
    Filed: July 23, 2007
    Date of Patent: February 7, 2012
    Assignee: Nocil, Ltd
    Inventors: Chandrashekhar Shankar Inamdar, Chinmoy Nandi, Narendra Digambar Gangal
  • NOVEL SULFENAMIDE ACCELERATORS FOR IMPROVED NETWORK STABILIZATION OF RUBBER VULCANIZATES
    Publication number: 20100234535
    Abstract: Sulfenamide derivatives of 4-alkyl substituted 2-mercapto benzothiazole (4m-MBT) as accelerators used in vulcanizable rubber composition having improved ‘Reversion Resistance’ and ‘Modulus & Hardness Stabilization’ properties for sulphur vulcanized tire compounds predominantly based on Natural Rubber or its blends with Polybutadiene (BR) and styrene butadiene rubber (SBR) in which Natural Rubber is the major component thereby improving the overall tire performance, ride safety and tyre service life.
    Type: Application
    Filed: July 23, 2007
    Publication date: September 16, 2010
    Inventors: Chandrashekhar Shankar Inamdar, Chinmoy Nandi, Narendra Digambar Gangal