Hydrophilic synthetic polymers for soft contact lenses

A process for preparing a hydrophilic synthetic polymer usable as soft contact lenses is provided. The process comprises copolymerizing 20 parts (by wt.) of 2-hydroxyethyl methacrylate with 0.5 to 3 parts of vinyl acetate and 0.1 to 1 part of a cross-linking monomer (A). The polymerization is carried out either catalytically or by radiation. The resulting copolymer is mechanically fabricated and then swollen with water to give soft contact lenses. The lenses are stable both dynamically and optically, do not injure the cornea, and are capable of correcting regular astigmatism. In one example, 20 parts of 2-hydroxyethyl methacrylate were copolymerized in a mold with 1 part of vinyl acetate and 0.5 part of divinylbenzene (A) by irradiation with Co 60 radiation (1 x107 r) and then thermally treated. A transparent hydrophilic polymer usable as soft contact lenses was obtained. (Kaichi, S.)