REINFORCED PLATE GLASS AND METHOD FOR MANUFACTURING THE SAME

• US 20100119846A1
• Filed: 03/03/2008
• Published: 05/13/2010
• Est. Priority Date: 03/02/2007
• Status: Abandoned Application

• Current Assignee: Nippon Electric Glass Company Limited
• Original Assignee: Nippon Electric Glass Company Limited
• Inventors: Sawada, Masahiro
• Application Number:
  US12/528,693
• Publication Number:
  US 20100119846A1
• Time in Patent Office: Days
• US Class Current: 428/426
• CPC Class Codes: C03B 33/023 the sheet or ribbon being in a horizontal position
• CPC Class Codes: C03B 33/027 Scoring tool holders; Driving mechanisms therefor
• CPC Class Codes: C03B 33/033 Apparatus for opening score lines in glass sheets
• CPC Class Codes: C03B 33/04 Cutting or splitting in curves, especially for making spectacle lenses
• CPC Class Codes: C03B 33/074 Glass products comprising an outer layer or surface coating of non-glass material
• CPC Class Codes: C03B 33/091 using at least one focussed radiation beam, e.g. laser beam C03B33/0955 takes precedence
• CPC Class Codes: C03C 19/00 Surface treatment of glass, not in the form of fibres or filaments, by mechanical means sand-blasting, grinding, or polishing glass B24
• CPC Class Codes: C03C 21/002 to perform ion-exchange between alkali ions C03C21/005 takes precedence
• CPC Class Codes: C03C 23/0025 by a laser beam
• CPC Class Codes: C03C 23/007 by thermal treatment
• CPC Class Codes: C03C 3/085 containing an oxide of a divalent metal
• CPC Class Codes: C03C 3/091 containing aluminium
• CPC Class Codes: C03C 3/093 containing zinc or zirconium
• CPC Class Codes: Y02P 40/57 Improving the yield, e-g- reduction of reject rates

Abstract

[Object] To provide a method of manufacturing a reinforced plate glass by which glass surface strength can be sufficiently increased, and a stable quality reinforced plate glass is manufactured at high production efficiency, and to provide a reinforced plate glass manufactured by the manufacturing method.

[Solving Means] A reinforced plate glass (10) is formed of an inorganic oxide glass, and is provided with a compression stress layer by chemical reinforcement on plate surfaces (11, 12) opposed to each other in a plate thickness direction. Plate end faces (13, 14, 15, 16) have regions where a compression stress is formed and regions where no compression stress is formed.

Claims

1. A reinforced plate glass made of an inorganic oxide glass, comprising a compression stress layer formed by chemical reinforcement on each of plate surfaces opposed to each other in a plate thickness direction, and a region where a compression stress is formed and a region where a compression stress is not formed on a plate end face.

2. The reinforced plate glass according to claim 1, wherein the region where a compression stress is formed is distributed in parallel with the plate surface on the plate end face.

3. The reinforced plate glass according to claim 1, wherein a stress distribution of the compression stress layer in a plate thickness direction is limited in accordance with a compression stress function represented by a compression stress value of the plate surface, a thickness size of the compression stress layer, and a thickness size of the region where a compression stress is not formed.

4. The reinforced plate glass according to claim 1, wherein the compression stress function is a function obtained by dividing a product of the compression stress value and the thickness size of the compression stress layer by the thickness size of the region where a compression stress is not formed, and a value calculated by the function is 40 MPa or less.

5. The reinforced plate glass according to claim 1, wherein a compression stress value of at least one of the plate surfaces is in a range of from 200 to 1,500 MPa.

6. The reinforced plate glass according to claim 1, wherein an average breaking stress by a four-point bending test according to JIS R1601 (1995) is 400 MPa or more, and a Weibull coefficient according to JIS R1625 (1996) is 3 or more.

7. The reinforced plate glass according to claim 1, comprising 50 to 80% of SiO₂, 0 to 15% of B₂O₃, 3 to 25% of Al₂O₃, 0 to 20% of Li₂O, 0 to 20% of Na₂O, 3 to 25% of Li₂O+Na₂O, 0 to 20% of K₂O, 0 to 10% of CaO+MgO+ZnO+SrO+BaO, and 0 to 10% of TiO₂+ZrO₂, represented by percent by mass of an oxide conversion.

8. The reinforced plate glass according to claim 1, wherein the plate end face is a surface formed by physical processing.

9. The reinforced plate glass according to claim 1, wherein the physical processing is any one of laser cutting and scribe cleaving.

10. A method of manufacturing a reinforced plate glass, comprising a compression reinforcement step of forming a compression stress layer on a surface of a plate glass by chemical reinforcement and a dividing step of applying a tensile stress to a plate surface of the plate glass chemically reinforced by the compression reinforcement step and dividing the plate glass, to thereby obtain the reinforced glass according to claim 1.

11. The method of manufacturing a reinforced plate glass according to claim 10, wherein a stress distribution in a plate thickness direction of a compression stress layer of the plate surface is limited in accordance with a compression stress function represented by a compression stress value of the plate surface, a thickness size of the compression stress layer, and a thickness size of a region where a compressive force is not formed, due to the compression reinforcement step.

12. The method of manufacturing a reinforced plate glass according to claim 11, wherein the dividing step is conducted by any one of laser cutting and scribing cleaving.

13. The method of manufacturing a reinforced plate glass according to claim 12, wherein the scribing cleaving is conducted under a force applying condition of from 0.5 to 1.5 kgf with respect to the plate surface.

14. The method of manufacturing a reinforced plate glass according to claim 12, wherein the scribing cleaving is conducted at a scribing speed of from 10 to 1,000 mm/s.

15. The method of manufacturing a reinforced plate glass according to claim 12, wherein the laser cutting is conducted by laser light radiated by a carbon dioxide laser light source with an output of from 10 to 100 W.

16. The method of manufacturing a reinforced plate glass according to claim 11, wherein the laser cutting is conducted by operating radiation light at a transfer speed of from 5 to 100 mm/s with respect to a plate glass surface.

17. The reinforced plate glass according to claim 2, wherein a stress distribution of the compression stress layer in a plate thickness direction is limited in accordance with a compression stress function represented by a compression stress value of the plate surface, a thickness size of the compression stress layer, and a thickness size of the region where a compression stress is not formed.

18. The reinforced plate glass according to claim 3, wherein the compression stress function is a function obtained by dividing a product of the compression stress value and the thickness size of the compression stress layer by the thickness size of the region where a compression stress is not formed, and a value calculated by the function is 40 MPa or less.

19. The reinforced plate glass according to claim 17, wherein the compression stress function is a function obtained by dividing a product of the compression stress value and the thickness size of the compression stress layer by the thickness size of the region where a compression stress is not formed, and a value calculated by the function is 40 MPa or less.

20. The reinforced plate glass according to claim 2, wherein a compression stress value of at least one of the plate surfaces is in a range of from 200 to 1,500 MPa.