Patents Represented by Attorney William J. Fisher
  • Patent number: 5219572
    Abstract: A controlled release delivery device for macromolecular proteins which comprises a water-soluble outer capsule completely surrounding an inner compartment containing a plurality of non-uniform beadlets. The beadlets comprise a rupturable wax shell which completely surrounds a core matrix containing the macromolecular proteins and optional "core agents" such as excipients, stabilizers, binders, surfactants, preservatives, or mixtures thereof, and the like.The water-soluble outer capsule dissolves when the device is administered to an animal and simultaneously exposes substantially all of the beadlets to an aqueous environment. Each beadlet absorbs fluid from the environment and separately ruptures over a prolonged period thus delivering the macromolecular protein to the animal.
    Type: Grant
    Filed: July 25, 1991
    Date of Patent: June 15, 1993
    Assignee: Pitman-Moore, Inc.
    Inventors: Kallidaikurichi N. Sivaramakrishnan, Lindy F. Miller
  • Patent number: 5165907
    Abstract: A method for producing high purity silica and ammonium fluoride from silicon tetrafluoride-containing gas wherein silicon tetrafluoride-containing gas from the acidulation of phosphorus-containing rock is recovered and the liquid entrainment is separated from the gas. The recovered gas is converted to an ammonium fluosilicate solution and is ammoniated to produce high purity silica and ammonium fluoride. The recovered gas can be converted to an ammonium fluosilicate solution either by absorbing the gas directly in a solution of ammonium fluoride or by first absorbing the gas in water to produce fluosilicic acid and then reacting the fluosilicic acid with ammonia or ammonium fluoride.
    Type: Grant
    Filed: December 31, 1990
    Date of Patent: November 24, 1992
    Assignee: IMCERA Group Inc.
    Inventor: Paul C. Chieng
  • Patent number: 5158758
    Abstract: A method for production of high specific surface area silica gel by hydrolysis of silicon tetrahalide, wherein a solution of silicon tetrahalide in a non-reactive solvent such as alcohol is mixed with water to produce silica gel having a high surface area and narrow pore diameter distribution especially suited for use as normal phase packing material in high performance chromatography columns. The water contains fluoride ions if the halide is chloride. Reverse phase packing material can be prepared by reacting the normal phase silica gel with organochlorosilanes to prepare bonded reverse phase material for use in high performance liquid chromotagraphy systems.
    Type: Grant
    Filed: April 24, 1989
    Date of Patent: October 27, 1992
    Assignee: International Minerals & Chemical Corp.
    Inventors: Paul C. Chieng, Deborah J. Brame, Alexander H. T. Chu
  • Patent number: 5030433
    Abstract: A method of producing pure and dense amorphous fused synthetic silica. Silica of desired purity is wet pelletized or agglomerated to form particles having an average particle size of between about 5 and 2500 microns. These particles are calcined to volatilize impurities and increase density to at least about 0.9 g/cm.sup.3. Calcined particles are classified by size or reduced in size if desired or needed by grinding in such a way that the purity of the product is maintained.
    Type: Grant
    Filed: July 18, 1988
    Date of Patent: July 9, 1991
    Assignee: International Minerals & Chemical Corp.
    Inventor: Vikram P. Mehrotra
  • Patent number: 5028407
    Abstract: A method of producing a high purity silica powder which can be fused to form transparent, bubble-free particles. An ammonium fluosilicate solution is purified preliminarily by removing colloidal-sized silica onto which impurities in the solution have been adsorbed. The high purity powder is produced by ammoniation of an unsaturated aqueous solution of ammonium fluosilicate. Silica powder produced is filtered, washed, and dried before fusion. Additional pre-fusion treatments such as washing, hydrothermal leaching, calcination, and a combination thereof, may be utilized to ensure that the concentration of volatile material is low.
    Type: Grant
    Filed: January 25, 1990
    Date of Patent: July 2, 1991
    Assignee: International Minerals & Chemical Corp.
    Inventors: Paul C. Chieng, Vikram P. Mehrotra, Chin-Liang Chou