Patents by Inventor Tarun K. S. Gupta

Tarun K. S. Gupta 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).

  • Aluminium articles having anodic oxide coatings and methods of coloring them by means of optical interference effects
    Patent number: 4310586
    Abstract: The invention provides aluminium articles having porous anodic oxide films colored by means of an optical interference effect. In FIG. 4, the article 10 carries a first anodic oxide film 12 with pores 14 enlarged at their inner ends 20 and containing deposits 22. The products may be made by growing a second anodic oxide film 26 underneath the deposits 22 which are preferably of acid-resistant material. X is at least 26 nm, Y is preferably at least 60 nm, Z is preferably 15 nm to 200 nm, (Y+Z) is preferably 75 nm to 600 nm, and W is preferably at least 15 nm.
    Type: Grant
    Filed: April 17, 1980
    Date of Patent: January 12, 1982
    Assignee: Alcan Research and Development Limited
    Inventors: Peter G. Sheasby, Graham Cheetham, Rainer W. M. Stuckart, Tarun K. S. Gupta
  • Electrolytic coloring of anodized aluminium by means of optical interference effects
    Patent number: 4251330
    Abstract: In a process for the electrocoloring of anodized aluminium in which colors are obtained by interference effects the pores of an anodic oxide film, produced by D.C. anodizing in sulphuric acid, are enlarged by electrolytic treatment in an acid electrolyte having a high dissolving power for aluminium oxide under alternating current conditions.
    Type: Grant
    Filed: January 16, 1979
    Date of Patent: February 17, 1981
    Assignee: Alcan Research and Development Limited
    Inventors: Peter G. Sheasby, Edward P. Short, Tarun K. S. Gupta