Flat glass, method for producing same, and use thereof
A flat glass is provided that exhibits high transmittance to electromagnetic radiation in a range of wavelengths from 200 nm to 1500 nm. The transmittance for the flat glass having a thickness of 1 mm is 20% or more at a wavelength of 254 nm, 82% or more at a wavelength of 300 nm, 90% or more at a wavelength of 350 nm, 92% or more at a wavelength of 546 nm, 92.5% or more at a wavelength of 1400 nm, 91.5% or more in a wavelength range from 380 nm to 780 nm, and 92.5% or more in a wavelength range from 780 nm to 1500 nm.
1. A flat glass comprising a transmittance to electromagnetic radiation for glass having a thickness of 1 mm that is 20% or more at a wavelength of 254 nm, 82% or more at a wavelength of 300 nm, 90% or more at a wavelength of 350 nm, 92% or more at a wavelength of 546 nm, 92.5% or more at a wavelength of 1400 nm, 91.5% or more in a wavelength range from 380 nm to 780 nm, and 92.5% or more in a wavelength range from 780 nm to 1500 nm, wherein the flat glass comprises B 2 O 3 , and wherein the flat glass further comprises a ratio of weight fractions of ions of iron that is 0.1≤Fe 2+ /(Fe 2+ +Fe 3+ )≤0.3 and comprises a ratio of molar amounts Σ(Me x O y )/(Σ(SiO 2 +B 2 O 3 ) between 0.02 to 0.10, wherein Me is selected from a group consisting of an alkali metal, an alkaline earth metal, and aluminum.
2. The flat glass of claim 1 , wherein the transmittance is 60% or more at the wavelength of 254 nm, 90% or more at the wavelength of 300 nm, 91% or more at the wavelength of 350 nm, 92.5% or more at the wavelength of 546 nm, 93% or more at the wavelength of 1400 nm, 92% or more in the wavelength range from 380 nm to 780 nm, and 93% or more in the wavelength range from 780 nm to 1500 nm.
3. The flat glass of claim 2 , wherein the transmittance is 85% or more at a wavelength of 254 nm and 91% or more at a wavelength of 300 nm.
4. The flat glass of claim 3 , wherein the transmittance is 88% or more at a wavelength of 254 nm.
5. The flat glass of claim 1 , further comprising a content of oxides of network formers of not more than 98 mol % in total.
6. The flat glass of claim 5 , wherein the oxides of network formers comprise oxides of silicon and/or boron.
7. The flat glass of claim 1 , further comprising a coefficient of linear thermal expansion between 2.4*10 −6 /K and 3.5*10 −6 /K.
8. The flat glass of claim 1 , further comprising a content of SiO 2 between 72 mol % and 85 mol %.
9. The flat glass of claim 1 , further comprising a content of B 2 O 3 between 10 mol % and 25 mol %.
10. The flat glass of claim 1 , further comprising Σ(SiO 2 +B 2 O 3 ) of 92 mol % to 98 mol %.
11. The flat glass of claim 1 , further comprising ΣR 2 O that is between 1 mol % and 5 mol %, wherein R 2 O is alkali metal oxides.
12. The flat glass of claim 1 , further comprising a ratio of molar amounts of B 2 O 3 /SiO 2 between 0.12 to 0.35.
13. The flat glass of claim 1 , wherein for the weight fractions, in ppm, of Fe, Co, Ni, Cr, Cu, Mn, and V, the following applies: Σ(1*Fe+300*Co+70*Ni+50*Cr+20*Cu+5*Mn+2*V) [ppm by mass] is less than 200 ppm, wherein a total content of considered metals is considered irrespective of an oxidation state thereof.
14. The flat glass of claim 1 , further comprising a transformation temperature between 450° C. and 550° C.
15. The flat glass of claim 1 , further comprising having a viscosity η, wherein Ig η has a value of 4 at temperatures between 1000° C. and 1320° C.
16. The flat glass of claim 1 , further comprising a refractive index at a light wavelength of 587.6 nm that is less than 1.475.
17. The flat glass of claim 1 , further comprising a value of chemical resistance against water according to DIN ISO 719 class HGB 1, a value of chemical resistance against acids according to DIN 12116 class S 1 W; and a value of chemical resistance against alkalis according to DIN ISO 695 class A3 or better.
18. The flat glass of claim 1 , comprising:
SiO 2
72 mol % to 85 mol %,
B 2 O 3
10 mol % to 25 mol %,
Al 2 O 3
0.2 mol % to 2.5 mol %,
Na 2 O
0.5 mol % to 5.0 mol %,
K 2 O
0 mol % to 1.0 mol %, and
Li 2 O
0 mol % to 1.5 mol %.
19. The flat glass of claim 18 , wherein the Na 2 O, K 2 O, Li 2 O amount to less than 5 mol % in total.