Patent ID: 7165840

Claim:
A method of manufacturing a contact lens having a mark, said method comprising the steps of: providing a mold assembly for polymerization comprising a male mold and a female mold which cooperate with each other to define a mold cavity therebetween having a configuration sufficient to provide a contact lens at least one of said male and said female molds comprising a resin; and forming said contact lens by polymerizing a predetermined monomer mixture in said mold assembly, said contact lens forming step comprising the steps of roughening at least a portion of a molding surface of at least one of said male and female molds for a marker portion by sputtering to form a multiplicity of minute recesses, providing a coloring composition by dissolving or dispersing a predetermined dyestuff comprising a polymeric colorant having a polymerizable functional group in a medium composed of at least one monomer component of said monomer mixture of said contact lens, attaching said coloring composition to said portion of said molding surface that was roughened during said roughening step so that said coloring composition defines a predetermined shape of a mark in said marker portion, prepolymerizing said coloring composition in said marker portion after said coloring composition is attached to said molding surface in said marker portion, filling said monomer mixture of said contact lens into said mold cavity after said coloring composition is attached in said marker portion, and polymerizing said monomer mixture as said prepolymerization step is completed, so as to at least partially copolymerize said monomer mixture and said coloring composition in said marker portion to integrate a polymer formed from said monomer mixture of said contact lens with a polymer of said coloring composition in said marker portion.