Patents Assigned to William H. Webster
  • Patent number: 6162646
    Abstract: A urine pH indicator has a plurality of hydrophilic, non-ionic, polymer foam carrier particles. The carrier particles are impregnated with an indicator complex having more than one chromophore and indicating more than one pH threshold via at least three distinguishable colors. The carrier particles are preferable chopped and soaked in a solution containing the chromophore complex. Upon evaporation of the solvent, the chromophore complex is bound to the carrier particles which can then be spread upon animal litter to receive urine and indicate pH via color display.
    Type: Grant
    Filed: May 18, 1998
    Date of Patent: December 19, 2000
    Assignee: William H. Webster
    Inventors: William H. Webster, Alfred E. Fox