Patents by Inventor Narayan Das

Narayan Das 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: 4391652
    Abstract: A low pH solution and a method for conversion coating aluminum and aluminum alloy surfaces, as well as the coated surfaces themselves, utilizing zirconium, fluoride and nickel and, optionally, fluorophosphate.
    Type: Grant
    Filed: January 29, 1982
    Date of Patent: July 5, 1983
    Assignee: Chemical Systems, Inc.
    Inventors: Narayan Das, Joy M. Schaefer
  • Patent number: 4381064
    Abstract: A stock material for producing seamless containers from a black plate base includes applying a layer of insoluble crystalline phosphate to each surface of the black plate and subsequently producing a thin film of organic lubricating material on the exposed surfaces of the phosphate layers so that a drawn and ironed container can be produced from a flat blank without the use of any additional lubricants during fabrication. The weight of the phosphate layer for each surface of the black plate base is preferably less than 100 milligrams per square foot, while the weight of lubricating film is on the order of 70 to 360 milligrams per square foot. In the preferred embodiment, the phosphate layer is preferably in the range of 20 to 35 milligrams per square foot, and the lubricant layer is on the order of 70 to 180 milligrams per square foot.
    Type: Grant
    Filed: March 2, 1981
    Date of Patent: April 26, 1983
    Assignee: National Can Corporation
    Inventors: Narayan Das, Surya K. Misra
  • Patent number: 4285223
    Abstract: A stock material for producing seamless containers from a black plate base includes applying a layer of insoluble crystalline phosphate to each surface of the black plate and subsequently producing a thin film of organic lubricating material on the exposed surfaces of the phosphate layers so that a drawn and ironed container can be produced from a flat blank without the use of any additional lubricants during fabrication. The weight of the phosphate layer for each surface of the black plate base is preferably less than 100 milligrams per square foot, while the weight of lubricating film is on the order of 70 to 360 milligrams per square foot. In the preferred embodiment, the phosphate layer is preferably in the range of 20 to 35 milligrams per square foot, and the lubricant layer is on the order of 70 to 180 milligrams per square foot.
    Type: Grant
    Filed: February 12, 1979
    Date of Patent: August 25, 1981
    Inventors: Narayan Das, Surya K. Misra
  • Patent number: 3964936
    Abstract: An acidic aqueous coating solution for forming on an aluminum surface a coating which is corrosion resistant and to which overlying coatings adhere excellently is disclosed. The coating solution contains compounds of zirconium and fluorine. The use of boric acid in the solution is disclosed also. The coating solution is capable of forming on an aluminum surface a uniformly colorless and clear coating so that the coated surface has the appearance of the underlying metal surface, that is, the coating can be formed without changing the appearance of the metal surface. When coating a shiny bright aluminum surface, there can be produced a coated surface having a uniformly shiny bright appearance which is maintained even after the coated surface is subjected to boiling water.
    Type: Grant
    Filed: December 17, 1974
    Date of Patent: June 22, 1976
    Assignee: Amchem Products, Inc.
    Inventor: Narayan Das