Thin lithium-aluminosilicate glass for three dimensional precision molding
A thin lithium-aluminosilicate glass is provided. The glass is suitable for three dimensional precision molding and suitable for toughening, wherein after toughening, the glass has a center tension smaller than 50 Mpa, a surface compressive stress of 600-1200 Mpa, and a bending strength of up to 500 MPa. The glass also has a transition point lower than 550° C.
1. A thin lithium-aluminosilicate glass for three dimensional precision molding, comprising:
after toughening, a center tensile stress smaller than 50 MPa, a surface compressive stress of 500-1200 MPa, a bending strength of at least 500 MPa, and a glass transition point lower than 550° C.; and
a glass composition, based on the total weight, in weight percentage:
SiO 2
58-65
wt. %
Li 2 O
4.6-5.4
wt. %
Na 2 O
8.1-9.7
wt. %
K 2 O
0.01-1.0
wt. %
Al 2 O 3
16-20
wt. %
B 2 O 3
0.1-1.0
wt. %
MgO
0-0.1
wt. %
SrO
0-0.2
wt %
ZnO
0-0.5
wt. %
ZrO 2
2.5-5.0
wt. %
P 2 O 5
0-1
wt. %
Fe 2 O 3
0.008-0.2
wt. %
SnO 2
0.05-0.6
wt. %
CeO 2
0.01-0.3
wt. %
wherein:
(Li 2 O+Al 2 O 3 )/(Na 2 O+K 2 O) is greater than 2.0,
SnO 2 +CeO 2 +Fe 2 O 3 is greater than 0.1 wt. %, and
CaO+ZnO+P 2 O 5 +B 2 O 3 +CeO 2 +Fe 2 O 3 is greater than 0.8 wt. % and less than 2.0 wt. %.
2. The thin lithium-aluminosilicate glass according to claim 1 , wherein the center tensile stress is smaller than 30 MPa.
3. The thin lithium-aluminosilicate glass according to claim 2 , wherein the center tensile stress is smaller than 20 MPa.
4. The thin lithium-aluminosilicate glass according to claim 1 , wherein the surface compressive stress is 700-1200 MPa.
5. The thin lithium-aluminosilicate glass according to claim 4 , wherein the surface compressive stress is 800-1200 MPa.
6. The thin lithium-aluminosilicate glass according to claim 1 , wherein the bending strength is at least 600 MPa.
7. The thin lithium-aluminosilicate glass according to claim 1 , wherein the glass transition point is lower than 530° C.
8. The thin lithium-aluminosilicate glass according to claim 7 , wherein the glass transition point is lower than 520° C.
9. The thin lithium-aluminosilicate glass according to claim 8 , wherein the glass transition point is lower than 510° C.
10. The thin lithium-aluminosilicate glass according to claim 1 , wherein K 2 O is less than 0.5 wt. %.
11. The thin lithium-aluminosilicate glass to claim 10 , wherein K 2 O is less than 0.3 wt. %.
12. The thin lithium-aluminosilicate glass according to claim 1 , wherein ZnO is less than 0.4 wt. %.
13. The thin lithium-aluminosilicate glass according to claim 12 , wherein ZnO is less than 0.3 wt. %.
14. The thin lithium-aluminosilicate glass according to claim 1 , wherein CaO is less than 1.5 wt. %.
15. The thin lithium-aluminosilicate glass according to claim 14 , wherein CaO is less than 1.0 wt. %.
16. The thin lithium-aluminosilicate glass according to claim 1 , wherein P 2 O 5 is less than 0.5 wt. %.
17. The thin lithium-aluminosilicate glass according to claim 16 , wherein P 2 O 5 is less than 0.2 wt. %.
18. The thin lithium-aluminosilicate glass according to claim 1 , wherein B 2 O 3 is less than 0.8 wt. %.
19. The thin lithium-aluminosilicate glass according to claim 18 , wherein B 2 O 3 is less than 0.6 wt. %.
20. The thin lithium-aluminosilicate glass according to claim 1 , wherein ZrO 2 is less than 4.5 wt. %.
21. The thin lithium-aluminosilicate glass according to claim 20 , wherein ZrO 2 is less than 4.0 wt. %.
22. The thin lithium-aluminosilicate glass according to claim 1 , wherein SnO 2 is less than 0.5 wt. %.
23. The thin lithium-aluminosilicate glass according to claim 22 , wherein SnO 2 is less than 0.4 wt. %.
24. The thin lithium-aluminosilicate glass according to claim 1 , wherein Al 2 O 3 is from 17 to 19 wt. %.
25. The thin lithium-aluminosilicate glass according to claim 24 , wherein Al 2 O 3 is from 17.5 to 18.5 wt. %.
26. The thin lithium-aluminosilicate glass according to claim 1 , wherein Li 2 O is from 4.8 to 5.2 wt. %.
27. The thin lithium-aluminosilicate glass according to claim 1 , wherein Na 2 O is from 8.4 to 9.6 wt. %.
28. The thin lithium-aluminosilicate glass according to claim 27 , wherein Na 2 O is from 8.6 to 9.5 wt. %.
29. The thin lithium-aluminosilicate glass according to claim 1 , wherein CeO 2 is from 0.03 to 0.25 wt. %.
30. The thin lithium-aluminosilicate glass according to claim 29 , wherein CeO 2 is from 0.05 to 0.2 wt. %.
31. The thin lithium-aluminosilicate glass according to claim 1 , wherein the glass is free of As 2 O 3 and Sb 2 O 3 .
32. The thin lithium-aluminosilicate glass according to claim 1 , wherein the glass is molded into a 3D shape at a temperature between 500° C. and 700° C.
33. The thin lithium-aluminosilicate glass according to claim 7 , wherein the glass is molded into a 3D shape at a temperature between 500° C. and 650° C.
34. The thin lithium-aluminosilicate glass according to claim 8 , wherein the glass is molded into a 3D shape at a temperature between 500° C. and 630° C.
35. The thin lithium-aluminosilicate glass according to claim 9 , wherein the glass is molded into a 3D shape at a temperature between 500° C. and 600° C.
36. The thin lithium-aluminosilicate glass according to claim 1 , wherein the glass is a flat glass having a thickness between 0.4 mm and 2.0 mm.
37. The thin lithium-aluminosilicate glass according to claim 1 , wherein the glass is subjected to toughening in a molten composition selected from the group consisting of KNO 3 , NaNO 3 , and a mixed salt of molten NaNO 3 and KNO 3 .
38. The thin lithium-aluminosilicate glass according to claim 1 , wherein the glass is subjected to toughening in molten KNO 3 , and has a surface stress of 800-1200 MPa.
39. The thin lithium-aluminosilicate glass for according to claim 1 , wherein the glass is subjected to toughening in molten KNO 3 , and has a surface stress layer of at least 10 microns.
40. The thin lithium-aluminosilicate glass according to claim 1 , wherein the glass is subjected to toughening in molten NaNO 3 , and has a surface stress of 500-800 MPa.
41. The thin lithium-aluminosilicate glass according to claim 1 , wherein the glass is subjected to toughening in molten NaNO 3 , and has a surface stress layer of at least 50 microns.
42. The thin lithium-aluminosilicate glass according to claim 1 , wherein the glass is subjected to toughening in molten KNO 3 +NaNO, and has a surface stress of 600-1000 MPa.
43. The thin lithium-aluminosilicate glass according to claim 1 , wherein the glass is subjected to toughening in molten KNO 3 +NaNO 3 , and has a surface stress layer of at least 50 microns.
44. The thin lithium-aluminosilicate glass according to claim 1 , wherein the glass has a thickness ranging from 0.4 to 3.0 mm.
45. The thin lithium-aluminosilicate glass according to claim 1 , wherein the glass has a thickness ranging from 0.4 to 2.0 mm.
46. The thin lithium-aluminosilicate glass according to claim 1 , wherein the glass has a thickness ranging from 0.4 to 1.0 mm.
47. The thin lithium-aluminosilicate glass claim 1 , wherein the glass is suitable for use as a protective glass of a touchpad.
48. The thin lithium-aluminosilicate glass according to claim 1 , wherein the glass has a surface structure.