Patents by Inventor John Bernard Clarke

John Bernard Clarke 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).

  • Dispersants for emulsion paints
    Patent number: 6359058
    Abstract: A pigment dispersant, for instance for incorporation in an emulsion paint containing non-reactive or reactive pigment, is a water-soluble copolymer of monomer units derived from two or more monomers of the formula CH2═CR1—COOR2 wherein R1 is methyl in 75 to 85 mol % of the monomer units and is hydrogen in the remainder, and R2 is hydrogen or a cation in 75 to 85 mol % of the monomer units and is C1-8 alkyl in the remainder of the monomer units and wherein at least 80% of the R2 alkyl groups are butyl groups.
    Type: Grant
    Filed: November 18, 1999
    Date of Patent: March 19, 2002
    Assignee: Ciba Specialty Chemicals Water Treatments Ltd.
    Inventors: John Bernard Clarke, Christopher Robert Walker