GLASS SHEET

• US 20150030838A1
• Filed: 03/13/2013
• Published: 01/29/2015
• Est. Priority Date: 03/15/2012
• Status: Abandoned Application

• Current Assignee: Saint-Gobain Glass France (Compagnie De Saint-Gobain)
• Original Assignee: Saint-Gobain Glass France (Compagnie De Saint-Gobain)
• Inventors: Sellier, Julien, Gy, Rene, Pelletier, Stephanie
• Application Number:
  US14/384,629
• Publication Number:
  US 20150030838A1
• Time in Patent Office: Days
• US Class Current: 428/220
• CPC Class Codes: C03C 21/002 to perform ion-exchange between alkali ions C03C21/005 takes precedence
• CPC Class Codes: C03C 3/085 containing an oxide of a divalent metal
• CPC Class Codes: C03C 4/00 Compositions for glass with special properties
• CPC Class Codes: H01L 31/0481 characterised by the composition of the encapsulation material
• CPC Class Codes: H01L 31/0488 Double glass encapsulation, e.g. photovoltaic cells arranged between front and rear glass sheets
• CPC Class Codes: Y02E 10/50 Photovoltaic [PV] energy

Abstract

A glass sheet, the composition of which is of the lithium aluminosilicate type and includes at most 1% by weight of sodium oxide, the thickness of which is at most 2 mm, having a surface region under compression obtained by ion exchange and a central region under tension, such that the flexural stress at break in a ring-on-tripod test is at least 50 MPa, after Vickers indentation under a load of 120 N.

Claims

1. A lithium aluminosilicate glass sheet, a composition of which comprises at most 1% by weight of sodium oxide, a thickness of which is at most 2 mm, having a surface region under compression obtained by ion exchange and a central region under tension, such that a flexural stress at break in a ring-on-tripod test is at least 50 MPa, after Vickers indentation under a load of 120 N.

2. The lithium aluminosilicate glass sheet as claimed in claim 1, wherein the flexural stress at break in a ring-on-tripod test is at least 100 MPa, after Vickers indentation under a load of 120 N.

3. The lithium aluminosilicate glass sheet as claimed in claim 1, such that wherein the flexural stress at break in a ring-on-tripod test is at least 300 MPa, after Vickers indentation under a load of 10 N.

4. The lithium aluminosilicate glass sheet as claimed in claim 1, the thickness of which is at most 1.5 mm and at least 0.25 mm.

5. The lithium aluminosilicate glass sheet as claimed in claim 4, the thickness of which is at most 1.1 mm.

6. The lithium aluminosilicate glass sheet as claimed in claim 1, wherein an exchange depth is at least 40 micrometers.

7. The lithium aluminosilicate glass sheet as claimed in claim 1, such that the surface region under compression is obtained by ion exchange using sodium ions.

8. The lithium aluminosilicate glass sheet as claimed in claim 1, wherein the chemical composition comprises the following oxides in the ranges of contents by weight defined below:

9. The lithium aluminosilicate glass sheet as claimed in claim 8, wherein the content by weight of CaO is at most 3%.

10. The lithium aluminosilicate glass sheet as claimed in claim 8, wherein the chemical composition comprises the following oxides in the ranges of contents by weight defined below:

11. An electronic device, comprising at least one lithium aluminosilicate glass sheet as claimed in claim 1, as protective glass, visual display window, screen or decorative element.

12. A pocket or portable electronic device, comprising at least one lithium aluminosilicate glass sheet as claimed in claim 1 as protective glass.

13. A solar thermal or photovoltaic collector, comprising at least one lithium aluminosilicate glass sheet as claimed in claim 1.

14. A process for obtaining a lithium aluminosilicate glass sheet as claimed in claim 1, comprising stages of melting the glass, of forming, of cutting and of ion exchange.

15. The process as claimed in claim 14, wherein at least one ion exchange stage is carried out using a molten sodium salt chosen from a nitrate, sulfate, chloride or any one of their mixtures.

16. The lithium aluminosilicate glass sheet as claimed in claim 6, wherein the exchange depth is at least 300 micrometers.

17. The lithium aluminosilicate glass sheet as claimed in claim 9, wherein the content by weight of CaO is at most 1%.

18. The lithium aluminosilicate glass sheet as claimed in claim 10, wherein the chemical composition comprises the following oxides in the ranges of contents by weight defined below:

19. The electronic device as claimed in claim 11, wherein said electronic device is a smart phone, personal digital assistant, digital camera, multimedia player, computer, tablet or television.