Tinted contact lens and method of tinting with reactive dye and quaternary ammonium 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 quaternary salt to the tinting solution before the applying step.
Claims10
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 on 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 an ammonium quaternary salt to said tinting solution before said applying step.
An aqueous solution for tinting soft contact lenses, comprising effective amounts of a reactive dyestuff and an ammonium quaternary salt.
Dependencies are inferred from the claim text.