Patents by Inventor William J. Zegarski

William J. Zegarski 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).

  • Flux for phosphor particle size control
    Patent number: 5395554
    Abstract: An improved flux for use in preparing X-ray phosphors comprises an alkali metal sulfate, an alkali metal metaborate and, a strontium halide. By varying the concentration of the metaborate and strontium halide in the flux composition, the size and dry bulk density of the phosphor particles and the speed of the phosphor, respectively, can be controlled. Also disclosed is a process of making phosphors using the above flux, and X-ray intensifying screens containing such phosphors.
    Type: Grant
    Filed: February 7, 1994
    Date of Patent: March 7, 1995
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: David B. Hedden, William J. Zegarski
  • Process of making tantalate X-ray phosphors
    Patent number: 5310505
    Abstract: An improved flux for use in preparing X-ray phosphors comprises an alkali metal sulfate, an alkali metal metaborate and, optionally a strontium halide. By varying the concentration of the metaborate and strontium halide in the flux composition, the size and dry bulk density of the phosphor particles and the speed of the phosphor, respectively, can be controlled. Also disclosed is a process of making phosphors using the above flux, and X-ray intensifying screens containing such phosphors.
    Type: Grant
    Filed: December 16, 1992
    Date of Patent: May 10, 1994
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: David B. Hedden, William J. Zegarski
  • Process of preparing tantalate X-ray intensifying phosphors with improved X-ray to light conversion efficiency
    Patent number: 5141673
    Abstract: A process for preparing X-ray intensifying M' monoclinic tantalate phosphors by firing precursor oxides in a novel flux mixture of alkali metal sulfate/alkali metal or alkaline earth chloride/alkali metal metasilicate. Tantalate phosphors made in this manner have improved X-ray to light conversion efficiency. X-ray intensifying screens made from these phosphors have improved speed and can be used with good results with a plurality of X-ray film elements.
    Type: Grant
    Filed: December 17, 1990
    Date of Patent: August 25, 1992
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: William J. Zegarski
  • Mixed phosphor x-ray intensifying screens with improved resolution
    Patent number: 5069982
    Abstract: An X-ray intensifying screen made from a mixture of yttrium tantalate and lanthanum oxyhalide phosphors is described. This screen, when used to expose a silver halide element, e.g., conventional grain or tabular grain element, will produce superior image resolution compared to similar screens made using single phosphors alone.
    Type: Grant
    Filed: November 19, 1990
    Date of Patent: December 3, 1991
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: William J. Zegarski
  • Process of preparing tantalate X-ray intensifying phosphors with improved efficiency
    Patent number: 5064729
    Abstract: A process for preparing X-ray intensifying M' monoclinic tantalate phosphors by firing precursor oxides in a novel flux mixture containing a compound capable of producing an alkali metal oxide and an effective amount of an alkali metal metasilicate. Tantalate phosphors made in this manner have improved efficiency and purity. X-ray intensifying screens made from these phosphors have improved speed and can be used with good results with a plurality of X-ray film elements.
    Type: Grant
    Filed: December 17, 1990
    Date of Patent: November 12, 1991
    Assignee: E. I. du Pont de Nemours and Company
    Inventor: William J. Zegarski
  • Adhesion between phosphor and topcoat layers of an X-ray intensifying screen
    Patent number: 5017440
    Abstract: An improved X-ray intensifying screen element containing a topcoat layer comprising an acrylonitrile-styrene copolymer optionally mixed with a carboxylated acrylic polymer and an active, phosphor layer having an adhesion promoting amount of a soluble, inorganic salt as described. The improved element exhibits strong adhesion between the topcoat and active layers and is eminently suitable for the rough handling encountered when these elements are used in autochangers and the like.
    Type: Grant
    Filed: September 29, 1989
    Date of Patent: May 21, 1991
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: William D. Bills, Theodore P. Christini, Reid E. Kellogg, Richard B. Maynard, William J. Zegarski