Basecurve mold designs to maintain HEMA ring/basecurve adhesion

摘要

Designs for basecurves are disclosed which are designed to promote adhesion of an excess polymer HEMA ring to the basecurve during a demolding operation such that the excess polymer HEMA ring is removed along with the basecurve during the demolding operation. The basecurve mold designs promote and maintain adhesion of an excess polymer HEMA ring to the basecurve in a process for molding cast contact lenses in mold assemblies, each comprising a frontcurve and a spaced basecurve, and wherein a molded lens is formed therebetween. In an embodiment of the invention, the annular area of the basecurve mold can be formed with an annular step which includes projecting teeth positioned therearound which project into the excess polymer HEMA ring.