Tinted contact lens and method of manufacture thereof: reactive dye and quaternary phosphonium salt
AssigneeCiba-Geigy Corporation
InventorsWilliam M. Hung, Kai C. Su
Life of this patent
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Abstract
An improvement in a process for preparing a contact lens tinted over at least a portion of its surface, having the steps of forming a tinting solution having a reactive dyestuff and applying the tinting solution to a polymeric hydrogel contact lens material, wherein the improvement comprises adding an effective amount of an ammonium or phosphonium quaternary salt to the tinting solution before the applying step.
Claims13
An improvement in a process for preparing a soft contact lens tinted over at least a portion of its surface having the steps of forming an aqueous tinting solution comprising a reactive dyestuff and applying said tinting solution to a polymeric hydrogel contact lens material, wherein the improvement comprises adding an effective amount of a quaternary phosphonium salt to said tinting solution before said applying step.
A solution for tinting contact lenses, comprising effective amounts of a reactive dyestuff and a quaternary phosphonium salt.
Dependencies are inferred from the claim text.