Contact lenses and materials and methods of making same

A method of producing an optical lens blank having an interpenetrating network copolymer composition, said method comprising:

• preparing, in weight percent of the weight of all polymerizable vinyl monomers in the network copolymer composition (W/W), a first mixture of polymerizable vinyl monomers containing from about 5% to about 95% (W/W) of polymerizable vinyl monomers, from about 0.01% up to about 35% of a polymerizable monomeric vinyl crosslinking agent, and from about 0.1% up to about 3% (W/W) of a vinyl polymerization initiator;
• preparing a second mixture of polymerizable vinyl monomers containing from about 5% up to about 95% (W/W) of polymerizable vinyl monomers, from about 0.1% up to about 25% of a polymerizable monomeric vinyl crosslinking agent, and from about 0% up to about 0.3% (W/W) of a vinyl polymerization initiator;
• polymerizing said first mixture until said partially polymerized first mixture obtains a relative viscosity relative to said unpolymerized first mixture of from about 1.05 up to about 10;
• interrupting the polymerization of said partially polymerized first mixture by mixing said second mixture therein to create a casting solution therewith;
• introducing said casting solution into a mold having at least one lens finishing surface therein;
• closing said molds;
• heating said closed mold in the range of from about 20.degree. C. up to about 70.degree. C. for a time sufficient to complete the polymerization of said casting solution and create a lens blank having at least one optical surface in said mold;
• removing the closed mold from an oven;
• and removing said blank from said mold.