TEMPERED GLASS AND TEMPERED GLASS SHEET

• US 20120196110A1
• Filed: 01/17/2012
• Published: 08/02/2012
• Est. Priority Date: 01/19/2011
• Status: Abandoned Application

• Current Assignee: Nippon Electric Glass Company Limited
• Original Assignee: Nippon Electric Glass Company Limited
• Inventors: MURATA, Takashi, Tojyo, Takako, Kawamoto, Kosuke, Tomita, Yuusuke
• Application Number:
  US13/351,601
• Publication Number:
  US 20120196110A1
• Time in Patent Office: Days
• US Class Current: 428/220
• CPC Class Codes: C03B 25/08 of glass sheets
• CPC Class Codes: C03C 21/00 Treatment of glass, not in the form of fibres or filaments, by diffusing ions or metals in the surface
• CPC Class Codes: C03C 3/062 with less than 40% silica by weight
• CPC Class Codes: C03C 3/085 containing an oxide of a divalent metal
• CPC Class Codes: Y10T 428/315 Surface modified glass [e.g., tempered, strengthened, etc.]

Abstract

Provided is a tempered glass having a compression stress layer in a surface thereof, comprising, as a glass composition in terms of mol %, 50 to 75% of SiO₂, 3 to 13% of Al₂O₃, 0 to 1.5% of B₂O₃, 0 to 4% of Li₂O, 7 to 20% of Na₂O, 0.5 to 10% of K₂O, 0.5 to 13% of MgO, 0 to 6% of CaO, and 0 to 4.5% of SrO, and being substantially free of As₂O₃, Sb₂O₃, PbO, and F.

Claims

1. A tempered glass having a compression stress layer in a surface thereof, comprising, as a glass composition in terms of mol %, 50 to 75% of SiO₂, 3 to 13% of Al₂O₃, 0 to 1.5% of B₂O₃, 0 to 4% of Li₂O, 7 to 20% of Na₂O, 0.5 to 10% of K₂O, 0.5 to 13% of MgO, 0 to 6% of CaO, and 0 to 4.5% of SrO, and being substantially free of As₂O₃, Sb₂O₃, PbO, and F.

2. The tempered glass according to claim 1, which comprises, as a glass composition in terms of mol %, 50 to 75% of SiO₂, 4 to 13% of Al₂O₃, 0 to 1.5% of B₂O₃, 0 to 2% of Li₂O, 9 to 18% of Na₂O, 1 to 8% of K₂O, 0.5 to 12% of MgO, 0 to 3.5% of CaO, 0 to 3% of SrO, and 0 to 0.5% of TiO₂.

3. The tempered glass according to claim 1, which comprises, as a glass composition in terms of mol %, 50 to 75% of SiO₂, 4 to 12% of Al₂O₃, 0 to 1% of B₂O₃, 0 to 1% of Li₂O, 10 to 17% of Na₂O, 2 to 7% of K₂O, 1.5 to 12% of MgO, 0 to 3% of CaO, 0 to 1% of SrO, and 0 to 0.5% of TiO₂.

4. The tempered glass according to claim 1, which comprises, as a glass composition in terms of mol %, 55 to 75% of SiO₂, 4 to 11% of Al₂O₃, 0 to 1% of B₂O₃, 0 to 1% of Li₂O, 10 to 16% of Na₂O, 2 to 7% of K₂O, 3 to 12% of MgO, 0 to 3% of CaO, 0 to 1% of SrO, 0.5 to 10% of ZrO₂, and 0 to 0.5% of TiO₂.

5. The tempered glass according to claim 1, which comprises, as a glass composition in terms of mol %, 55 to 69% of SiO₂, 4 to 11% of Al₂O₃, 0 to 1% of B₂O₃, 0 to 1% of Li₂O, 11 to 16% of Na₂O, 2 to 7% of K₂O, 3 to 9% of MgO, 0 to 3% of CaO, 0 to 1% of SrO, 1 to 9% of ZrO₂, and 0 to 0.1% of TiO₂.

6. The tempered glass according to claim 1, wherein a compression stress value of the compression stress layer is 300 MPa or more, and a thickness of the compression stress layer is 10 μ

m or more.

7. The tempered glass according to claim 1, which has a degradation coefficient D of 0.01 to 0.6.

8. The tempered glass according to claim 1, which has a liquidus temperature of 1,075°

C. or less.

9. The tempered glass according to claim 1, which has a liquidus viscosity of 10^4.0 dPa·

s or more.

10. The tempered glass according to claim 1, which has a temperature at 10^4.0 dPa·

s of 1,250°

C. or less.

11. The tempered glass according to claim 1, which has a density of 2.6 g/cm³ or less.

12. The tempered glass according to claim 1, which has a Young'"'"'s modulus of 65 GPa or more.

13. A tempered glass sheet, comprising the tempered glass according to claim 1.

14. The tempered glass sheet according to claim 13, which is formed by a float method.

15. The tempered glass sheet according to claim 13, which has a surface formed by polishing by 0.5 μ

m or more in a thickness direction.

16. The tempered glass sheet according to claim 13, which has a Δ

CS value of 50 MPa or less, the Δ

CS value being a difference in compression stress value between compression stress layers in surfaces opposite to each other.

17. A tempered glass sheet having a compression stress in a surface thereof, the tempered glass sheet having a length of 500 mm or more, a width of 500 mm or more, a thickness of 0.5 to 1.5 mm, a Young'"'"'s modulus of 65 GPa or more, a compression stress value of a compression stress layer of 200 MPa or more, a thickness of a compression stress layer of 20 μ

m or more, a degradation coefficient D of 0.6 or less, and a Δ

CS value of 50 MPa or less, the Δ

CS value being a difference in compression stress value between compression stress layers in surfaces opposite to each other.

18. The tempered glass sheet according to claim 17, which is used for a touch panel display.

19. The tempered glass sheet according to claim 17, which is used for a cover glass for a cellular phone.

20. The tempered glass sheet according to claim 17, which is used for a cover glass for a solar battery.

21. The tempered glass sheet according to claim 17, which is used for a protective member for a display.

22. A tempered glass sheet having a compression stress in a surface thereof, the tempered glass sheet comprising, as a glass composition in terms of mol %, 50 to 75% of SiO₂, 4 to 12% of Al₂O₃, 0 to 1% of B₂O₃, 0 to 1% of Li₂O, 10 to 17% of Na₂O, 2 to 7% of K₂O, 1.5 to 12% of MgO, 0 to 3% of CaO, 0 to 1% of SrO, and 0 to 0.5% of TiO₂, and having a molar ratio MgO/(MgO+CaO) of 0.5 or more, a length of 500 mm or more, a width of 500 mm or more, a thickness of 0.5 to 1.5 mm, a Young'"'"'s modulus of 65 GPa or more, a compression stress value of a compression stress layer of 400 MPa or more, a thickness of a compression stress layer of 30 μ

m or more, and a degradation coefficient D of 0.4 or less.

23. A glass to be tempered to be subjected to tempering treatment, comprising, as a glass composition in terms of mol %, 50 to 75% of SiO₂, 3 to 13% of Al₂O₃, 0 to 1.5% of B₂O₃, 0 to 4% of Li₂O, 7 to 20% of Na₂O, 0.5 to 10% of K₂O, 0.5 to 13% of MgO, 0 to 6% of CaO, and 0 to 4.5% of SrO, and being substantially free of As₂O₃, Sb₂O₃, PbO, and F.

24. A glass sheet to be tempered, comprising a glass to be tempered to be subjected to tempering treatment, wherein the glass sheet to be tempered has a thickness of 1.5 mm or less, and has an Fmax value of 5 MPa or less, the Fmax value being a maximum value of residual stresses in a planar direction with respect to all planar portions of the glass to be tempered.