Patents by Inventor Ranvir Singh Virdi

Ranvir Singh Virdi 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 nitrosamine systems for rubber vulcanization
    Patent number: 6162875
    Abstract: A metal dialkyldithiocarbamate or other such compound including a group of the formula R.sub.2 NCS-- or R.sub.2 NS-- is useful as a rubber accelerator/vulcanizing agent, wherein each R is C.sub.5-18 branched alkyl.
    Type: Grant
    Filed: May 17, 1995
    Date of Patent: December 19, 2000
    Assignee: Robinson Brothers Limited
    Inventor: Ranvir Singh Virdi
  • Sulfur-containing amine compositions and agents for vulcanizing rubber
    Patent number: 5686536
    Abstract: A vulcanizable composition comprises sulfur-vulcanizable rubber, sulfur or a sulfur-donor, a zinc compound, and a sulfur-containing amine of the formulaR.sup.1 --S.sub.n --R--NR.sup.2 R.sup.3wherein R is a divalent radical comprising a chain of at least 2 C atoms, R.sup.1 is an organic radical, and R.sup.2 and R.sup.3 are each H or an organic radical, provided that NR.sup.2 R.sup.3 is not NH(C.sub.1-6 alkyl), and n is an integer, or a salt thereof, provided that the amine is not 3-(methylthio)propylamine. The amine is preferably cystamine.
    Type: Grant
    Filed: October 17, 1995
    Date of Patent: November 11, 1997
    Assignee: Robinson Brothers Limited
    Inventors: William Raymond Poyner, Khirud Behari Chakraborty, Ranvir Singh Virdi