| 摘要 |
PURPOSE: To maintain a bright-visional and easily visible state of an object without reducing visible light transmissivity of a lens under normal conditions by forming ultraviolet absorption layers on both surfaces of a lower part of half dimming plastic lens. CONSTITUTION: In this manufacture, a lower part 5 of a dimming plastic lens 2 is immersed for 5 to 30min in a solution obtained by dissolving an ultraviolet- absorbing agent in hot water of 70 to 90 deg.C to deposit the agent on the surfaces of the lower part 5 of the lens 2 and then, this lens 2 is taken out of the solution and dried to manufacture a half dimming plastic lens 1 having ultraviolet absorption layers 6 on its lower part 5. Accordingly, even when ultraviolet rays are incident on the lower part 5 of the lens 1, the rays are shielded by the ultraviolet absorption layers 6 and the lower part 5 is inhibited from being discolored by the effect of the absorption layers 6 to maintain its visible light transmissivity at about 90%. Also, since the whole surface of the lens 1 does not uniformly turn dark in color when ultraviolet rays are incident on the lens 1, this lens 1 has novelty that theretofore can not be attained and its fashonableness is improved. |
