| 摘要 |
Optically clear soft contact lenses of aqueous swollen solid polyvinyl alcohol having a weight average molecular weight of at least 6,000, having been annealed under crystallinity promoting conditions to a crystallinity degree of 0.195 to 0.7 to effectively increase the elastic modulus of the swollen lenses, and optionally subsequently crosslinked, and methods of preparation and the use thereof are disclosed. The lenses are characterized by their relatively high oxygen transmissibility, sufficient to meet the needs of the human cornea, high optical clarity, improved hot water resistance and superior mechanical properties. The lens may be tinted with dyes and pigments. |
