ULTRA-VIOLET RAY TRANSMITTING GLASS AND MICROPLATE USING THE SAME

摘要

An ultra-violet ray transmitting glass which contains, in mass %, 65 to 79 % of SiO2, 1 to 2 % of Al2O3, 0 to 10 % of B2O3, 0 to 10 % of MgO, 0 to 10 % of CaO, 0 to 15 % of SrO, 5 to 15 % of Na2O, 0 to 15 % of K2O, 0.002 % or less (in terms of Fe2O3) of total iron oxides, 0.002 % or less of TiO2, and 0.1 to 3 % of Cl. The above glass can exhibit, when it has a thickness of 1 mm, an ultraviolet ray transmittance of 40 % or more for the wavelength range of 240 to 300 nm, and, in combination with the above ultraviolet ray transmittance, can also have an average thermal expansion coefficient at 50 to 350°C of 80 to 100 x 10<-7>/°C.