Patents by Inventor Michael Hiew

Michael Hiew 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).

  • Continuous processes for producing titanium dioxide pigments
    Patent number: 6695906
    Abstract: Titanium dioxide pigments having improved gloss and durability are disclosed. These pigments are prepared by continuous processes, where pH, temperature, and addition times of hydrous silica and alumina coatings are carefully controlled.
    Type: Grant
    Filed: April 12, 2001
    Date of Patent: February 24, 2004
    Assignee: Millennium Inorganic Chemicals, Inc.
    Inventors: Michael Hiew, Yarw-Nan Wang, Les Hamor, Brian Tear, Robert McIntyre
  • Methods for producing titanium dioxide pigments having improved gloss at low temperatures
    Patent number: 6395081
    Abstract: The present invention provides methods of preparing a titanium dioxide pigment having improved gloss properties which involves heating an aqueous slurry of base titanium dioxide pigment to a temperature below about 75° C., coating the base titanium dioxide pigment with a silica compound at a temperature below about 75° C. to form a silica coated titanium dioxide pigment; and coating the silica coated titanium dioxide pigment with an alumina compound at a temperature below about 75° C. to form the titanium dioxide pigment having improved gloss.
    Type: Grant
    Filed: November 3, 2000
    Date of Patent: May 28, 2002
    Assignee: Millennium Inorganic Chemical, Inc.
    Inventors: Michael Hiew, Yarw-Nan Wang, Les Hamor, Brian Tear, Robert McIntyre
  • Continuous processes for producing titanium dioxide pigments
    Publication number: 20020017221
    Abstract: Titanium dioxide pigments having improved gloss and durability are disclosed. These pigments are prepared by continuous processes, where pH, temperature, and addition times of hydrous silica and alumina coatings are carefully controlled.
    Type: Application
    Filed: April 12, 2001
    Publication date: February 14, 2002
    Inventors: Michael Hiew, Yarw-Nan Wang, Les Hamor, Brian Tear, Robert McIntyre
  • Coated titanium dioxide pigments and processes for production and use
    Patent number: 6342099
    Abstract: The present invention provides a coated titanium dioxide pigment which includes a base titanium dioxide pigment; a first deposit of a phosphate compound contiguous with the base titanium dioxide pigment; a deposit of a silica or zirconia compound contiguous with the phosphate deposit; a second deposit of a phosphate compound contiguous with the silica or zirconia compound; and a deposit of an alumina compound contiguous with the second phosphate deposit. Titanium dioxide pigments of the present invention are easily dispersible, and display excellent durability and gloss.
    Type: Grant
    Filed: September 15, 2000
    Date of Patent: January 29, 2002
    Assignee: Millennium Inorganic Chemicals, Inc.
    Inventors: Michael Hiew, Philip Chegwidden