摘要 |
Provided are light-blocking lenses for safety glasses that block ultraviolet and visible light rays with a wavelength less than or equal to 430 nm, or widen the light-blocking range to a wavelength of less than or equal to 500 nm, and meet consumer demand for adjusting various color tones. The light-blocking lenses for safety glasses, which have an indole-based ultraviolet absorber with a melting point of 140 to 150°C blended in at 0.01 to 2 parts by mass with respect to 100 parts by mass of the lenses' synthetic resin, are preferably used together with an oil-soluble dye, and block ultraviolet and visible light rays with a wavelength less than or equal to 430 nm, are provided. By adequately dissolving a prescribed amount of the indole-based ultraviolet absorber in the synthetic resin, and efficiently exerting an effect, the lenses exhibit an improvement in light-blocking effect that was only been possible at or less than 400 nm in the conventional art, while having a highly-transparent pale color tone, and the lenses are capable of blocking ultraviolet or visible light rays with a wavelength of less than or equal to 430 nm, or less than or equal to 500 nm. |