| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide ultraviolet light-transmitting glass which has excellent transmittance in the ultraviolet region of 300 nm or less. <P>SOLUTION: Ultraviolet light-transmitting glass includes, in wt.% in terms of oxides, 10-40% of SiO<SB POS="POST">2</SB>, 10-40% of B<SB POS="POST">2</SB>O<SB POS="POST">3</SB>, 2-7.0% of Al<SB POS="POST">2</SB>O<SB POS="POST">3</SB>, 0-5% of Li<SB POS="POST">2</SB>O, 0-8% of Na<SB POS="POST">2</SB>O, 0-8.0% of K<SB POS="POST">2</SB>O (provided that Li<SB POS="POST">2</SB>O+Na<SB POS="POST">2</SB>O+K<SB POS="POST">2</SB>O=0-10%), 0-40% of CaO, 0-40% of BaO, 0-10% of ZnO (provided that CaO+BaO+MgO+SrO+ZnO=1-40%), 0-17% of Y<SB POS="POST">2</SB>O<SB POS="POST">3</SB>, 0-18.0% of ZrO<SB POS="POST">2</SB>, 0-15.0% of La<SB POS="POST">2</SB>O<SB POS="POST">3</SB>(provided that at least one of Y<SB POS="POST">2</SB>O<SB POS="POST">3</SB>, ZrO<SB POS="POST">2</SB>and La<SB POS="POST">2</SB>O<SB POS="POST">3</SB>is contained) and 0-0.5% of Sb<SB POS="POST">2</SB>O<SB POS="POST">3</SB>. By having fine crystals deposit, a sample of the ultraviolet light-transmitting glass having a thickness of 2.0 mm has a transmittance at 250 nm of 60% or more. <P>COPYRIGHT: (C)2013,JPO&INPIT |
