Clear glass composition
View Patent ↗Glass is provided so as to have high visible transmission and/or fairly clear or neutral color. In certain example embodiments, the clear glass includes a low amount of iron coupled with zinc oxide and/or erbium oxide in amounts designed to provide a neutral color. While the erbium oxide is used to provide for neutral color, the zinc oxide binds sulfur into whitish-colored zinc sulfide thereby reducing the amount of sulfur that binds/bonds with iron in the glass to form sulfides of iron which is/are brownish in color. Thus, the use of the zinc oxide helps make the glass more neutral in color. In certain example embodiments, the use of the erbium oxide brings the a* color value of the resulting glass closer to zero, whereas the use of the zinc oxide brings the b* value of the resulting glass closer to zero.
1. Glass comprising:
Ingredient
wt. %
SiO 2
67-75%
Na 2 O
10-20%
CaO
5-15%
total iron (expressed as Fe 2 O 3 )
0.0005 to 0.20%
erbium oxide
0.0001 to 0.20%
zinc oxide
0.01 to 3%
wherein the glass has visible transmission of at least 85%, a transmissive a* color value of from −0.20 to +0.15, and a transmissive b* color value of −0.15 to +0.20.
2. The glass of claim 1 , wherein the glass has visible transmission of at least 90%, a transmissive a* color value of from −0.15 to +0.10, and a transmissive b* color value of −0.10 to +0.15.
3. The glass of claim 1 , wherein the glass has visible transmission of at least 91%.
4. The glass of claim 1 , wherein the glass has a transmissive a* color value of from −0.10 to +0.05, and a transmissive b* color value of −0.10 to +0.10.
5. The glass of claim 1 , wherein the glass further comprises from about 0-1% aluminum oxide, and from about 0.1 to 3% of an oxide of strontium.
6. The glass of claim 1 , wherein the glass further comprises from about 0.1 to 1.5% of an oxide of strontium.
7. The glass of claim 1 , wherein the glass further comprises from about 0.1 to 0.6% of an oxide of strontium.
8. The glass of claim 1 , wherein the glass comprises
total iron (expressed as Fe 2 O 3 )
0.001 to 0.08%
erbium oxide
0.0005 to 0.10%
zinc oxide
0.01 to 2%.
9. The glass of claim 1 , wherein the glass comprises
total iron (expressed as Fe 2 O 3 )
0.001 to 0.06%
erbium oxide
0.0005 to 0.05%
zinc oxide
0.01 to 3%.
10. The glass of claim 1 , wherein the glass comprises
total iron (expressed as Fe 2 O 3 )
0.001 to 0.05%
erbium oxide
0.009 to 0.03%
zinc oxide
0.3 to 2%.
11. The glass of claim 1 , wherein the glass comprises from 0 to 0.07% cerium oxide.
12. The glass of claim 1 , wherein the glass comprises from 0 to 0.003% cerium oxide.
13. The glass of claim 1 , wherein the glass comprises 0% cerium oxide.
14. The glass of claim 1 , wherein the glass is substantially free of cerium, nickel, and selenium.
15. The glass of claim 1 , wherein the glass is substantially free of cobalt.
16. The glass of claim 1 , wherein the glass has a redox value (FeO/Fe 2 O 3 ) of from about 0.05 to 0.15.
17. Glass comprising:
Ingredient
wt. %
SiO 2
67-75%
Na 2 O
10-20%
CaO
5-15%
total iron (expressed as Fe 2 O 3 )
0.0005 to 0.20%
erbium oxide
0.0001 to 0.20%
zinc oxide
0 to 3%
strontium oxide
from about 0.1 to 3%.
wherein the glass has visible transmission of at least 90%, a transmissive a* color value of from −0.20 to +0.15, and a transmissive b* color value of −0.15 to +0.20.
18. The glass of claim 17 , wherein the glass has visible transmission of at least 91%, a transmissive a* color value of from −0.10 to +0.05, and a transmissive b* color value of −0.10 to +0.10.
19. The glass of claim 17 , wherein the glass further comprises from about 0-1% aluminum oxide.
20. The glass of claim 17 , wherein the glass further comprises from about 0.1 to 1.5% of an oxide of strontium.