| 摘要 |
PROBLEM TO BE SOLVED: To prevent loss, damage, crack or the like of a lens by a method wherein a surplus polymer HEMA ring is formed in the circumference of a central lens mold part and an annular region of a base curve mold is brought into contact with the surplus polymer HEMA ring so that the surface area of the base curve mold is increased and that sticking is enhanced at the time of mold release. SOLUTION: A mold cavity for a contact lens is formed between a lower recessed mold part and an upper projecting mold part, i.e., a base curve mold. A surplus polymer HEMA ring is formed at the time of mold release of a molded article and a roughened surface is provided on the base curve mold, in a circumferential annular region 50 wherein sticking of the surplus polymer ring to a base curve is to be enhanced. For this roughened annular region 50, a roughened annular region of a main mold for casting the base curve mold is formed by laser beam machining. At the time of the operation of mold release of the molded article, according to this constitution, it is possible to enhance sticking of the surplus polymer HEMA ring to the base curve and to separate a formed contact lens easily from the lower-side mold without damaging it. |
