Lithium aluminosilicate glass with high modulus of elasticity, and method for producing same

1. A lithium aluminosilicate glass, comprising a composition, in mol %, of:

SiO 2

60-70;

Al 2 O 3

10-13;

B 2 O 3

0.0-0.9;

Li 2 O

 9.6-11.6;

Na 2 O

8.2-less than 10;

K 2 O

0.0-0.7;

MgO

0.0-0.2;

CaO

0.2-2.3;

ZnO

0.0-0.4;

ZrO 2

1.3-2.6;

P 2 O 5

0.0-0.5;

Fe 2 O 3

0.003-0.100;

SnO 2

0.0-0.3; and

CeO 2

0.004-0.200,

wherein said composition is in compliance with the following relations:

(Li 2 O+Al 2 O 3 )/(Na 2 O+K 2 O) greater than 2;

Li 2 O/(Li 2 O+Na 2 O+K 2 O) greater than 0.47 and less than or equal to 0.586;

CaO+Fe 2 O 3 +ZnO+P 2 O 5 +B 2 O 3 +CeO 2 greater than 0.8 and less than 3 with at least four out of six oxides included; and

wherein said lithium aluminosilicate glass exhibits a modulus of elasticity of at least 82 GPa and has a glass transition point T g of less than 540° C. and/or a working point of less than 1150° C.

2. The lithium aluminosilicate glass as claimed in claim 1 , wherein said lithium aluminosilicate glass is suitable for shaping by a float process.

3. The lithium aluminosilicate glass as claimed in claim 2 , wherein said lithium aluminosilicate glass can be chemically and/or thermally tempered so that it has a flexural strength of at least 550 N/mm 2 , as measured with a double ring method according to EN 1288-5.

4. The lithium aluminosilicate glass as claimed in claim 3 , wherein said lithium aluminosilicate glass is chemically tempered by exchanging Li ions for ions having a greater ionic radius.

5. The lithium aluminosilicate glass as claimed in claim 1 , further comprising a linear coefficient of thermal expansion α (20-300) between 8.0*10 −6 K −1 and 9.0*10 −6 K −1 .

6. The lithium aluminosilicate glass as claimed in claim 1 , wherein at least two components from a group of refining components consisting of Fe 2 O 3 , CeO 2 , and SnO 2 together account for at least 0.1 mol % of said composition.

7. The lithium aluminosilicate glass as claimed in claim 6 , wherein said lithium aluminosilicate glass is free of TiO 2 and/or MgO and/or As 2 O 3 and/or Sb 2 O 3 and/or V 2 O 5 and/or Bi 2 O 3 and/or PbO, except for technically or economically unavoidable residues in glass raw materials.

8. The lithium aluminosilicate glass as claimed in claim 1 , wherein SnO 2 is present in a content of not more than 0.5 wt %.

9. The lithium aluminosilicate glass as claimed in claim 1 , wherein said composition comprises:

SiO 2

62-68;

Al 2 O 3

10-12;

B 2 O 3

0.0-0.7;

Li 2 O

10.1-11.1;

Na 2 O

8.6-9.8;

K 2 O

0.0-0.3;

MgO

0.00-0.08;

CaO

0.5-1.7;

ZnO

0.0-0.2;

ZrO 2

1.5-2.1;

P 2 O 5

0.0-0.3;

Fe 2 O 3

0.003-0.080;

SnO 2

0.05-0.30; and

CeO 2

0.04-0.10.

10. The lithium aluminosilicate glass as claimed in claim 1 , wherein said composition comprises:

SiO 2

63-67;

Al 2 O 3

10.8-11.5;

B 2 O 3

0.1-0.6;

Li 2 O

10.3-10.8;

Na 2 O

9.0-9.5;

K 2 O

0.1-0.3;

MgO

0.00-0.05;

CaO

0.6-1.4;

ZnO

0.0-0.1;

ZrO 2

1.6-2.0;

P 2 O 5

0.0-0.1;

Fe 2 O 3

0.003-0.080;

SnO 2

0.1-0.2; and

CeO 2

0.04-0.07.

11. The lithium aluminosilicate glass as claimed in claim 1 , wherein said lithium aluminosilicate glass is suitable for use as a high-strength pane or glazing having high compressive strengths and stiffness.

12. The lithium aluminosilicate glass as claimed in claim 1 , wherein said lithium aluminosilicate glass is suitable for use as an article selected from the group consisting of a glass body for vehicle glazings, as a substrate for electronic modules, as a substrate for solar modules, as a component for solar modules, as a control element of touchpad or touch panel device, as a substrate for a hard disk, and as a cover or display for a mobile telecommunications device.

13. A method for producing a lithium aluminosilicate glass article having a modulus of elasticity of at least 82 GPa and a glass transition point below 540° C. and/or a working point below 1150° C., comprising:

preparing a glass melt having a composition, in mol %, of:

SiO 2

60-70;

Al 2 O 3

10-13;

B 2 O 3

0.0-0.9;

Li 2 O

 9.6-11.6;

Na 2 O

8.2-less than 10;

K 2 O

0.0-0.7;

MgO

0.0-0.2;

CaO

0.2-2.3;

ZnO

0.0-0.4;

ZrO 2

1.3-2.6;

P 2 O 5

0.0-0.5;

Fe 2 O 3

0.003-0.100;

SnO 2

0.0-0.3; and

CeO 2

0.004-0.200,

wherein said composition is in compliance with the following relations:

(Li 2 O+Al 2 O 3 )/(Na 2 O+K 2 O) greater than 2;

Li 2 O/(Li 2 O+Na 2 O+K 2 O) greater than 0.47 and less than or equal to 0.586;

CaO+Fe 2 O 3 +ZnO+P 2 O 5 +B 2 O 3 +CeO 2 greater than 0.8 and less than 3; and

forming said lithium aluminosilicate glass article by a float process.

14. The method as claimed in claim 13 , wherein at least two components from a group of refining components consisting of Fe 2 O 3 , CeO 2 , and SnO 2 together account for at least 0.1 mol % of said composition.

15. The method as claimed in claim 13 , further comprising adding in halogenide salts refining components in a range from 0.2 to 2.0 wt % of said composition.

16. The method as claimed in claim 15 , wherein said halogenide salts comprise NaCl and/or KCl.

17. The method as claimed in claim 13 , further comprising adding a sulfate to said composition as a refining component.

18. The method as claimed in claim 17 , further comprising thermally tempering said lithium aluminosilicate glass article.

19. The method as claimed in claim 18 , wherein the step of thermally tempering comprise using a conventional air tempering system for soda-lime glass with heat transfer coefficients from 200 to 500 W m −2 K −1 at a blowing pressure from 1 to 9 kPa.

20. The method as claimed in claim 17 , further comprising chemically tempering said lithium aluminosilicate glass article by exchanging Li ions from said lithium aluminosilicate glass for ions having a greater ionic radius.