Marginally hinged, silicone rubber, contact lens - moulded by composite plunger with hinge-shaping edge zone

摘要

Mfr. of a flexible, pref. silicone rubber, contact lens with hinge-like annular zone, comprises press-moulding the lens by means of an at least 2-part stamp composed of concentric elements whose marginal zones serve to shape the hinge. Those regions of the resulting lens corresp. to the marginal zones of the stamp are polished after the press-moulding step. In addn., these regions may be perforated. Physiological compatibility is claimed to be improved i.e. the prod. gives wearer better tolerance. The perforated zones are suitably of narrower (or thinner) contour thus giving a hinge effect.