摘要 |
<P>PROBLEM TO BE SOLVED: To provide a light-shielding lens for protective eyeglasses that cuts off ultraviolet/visible light having a wavelength of 430 nm or less, or a wavelength range of 500 nm or less, and that responds to requests from consumers for adjustment of a wide variety of color tones. <P>SOLUTION: An ultraviolet absorber is mixed into an eyeglass lens made of synthetic resin to provide a light-shielding lens for protective eyeglasses that cuts off ultraviolet/visible light having a wavelength equal to or shorter than a predetermined value. Into 100 pts. mass of the synthetic resin is mixed 0.01 to 2 pts. mass of indole ultraviolet absorber having a melting point of 140 to 150°C, preferably in combination with oil-soluble dye, to provide a light-shielding lens for protective glasses that cuts off ultraviolet/visible light having a wavelength equal to or shorter than 430 nm. Effective exertion of a predetermined amount of the indole ultraviolet absorber that has sufficiently been dissolved into the synthetic resin improves the light-shielding property, which was conventionally effective only up to 400 nm, and ultraviolet/visible light having a wavelength up to 430 or 500 nm can be cut off though the color tone is pale with high transparency. <P>COPYRIGHT: (C)2012,JPO&INPIT |