Glass and chemically tempered glass

• US 8,349,455 B2
• Filed: 08/18/2010
• Issued: 01/08/2013
• Est. Priority Date: 09/18/2009
• Status: Active Grant

• Current Assignee: AGC, Inc.
• Original Assignee: Asahi Glass Company, Limited (AGC, Inc.)
• Inventors: Kondo, Yuki, Ohkawa, Hiroyuki, Sano, Makoto, Hayashi, Kazutaka, Akiba, Shusaku
• Primary Examiner(s): SAMPLE, DAVID R
• Application Number:
  US12/858,768
• Publication Number:
  US 20110071012A1
• Time in Patent Office: 874 Days
• Field of Search: 501 68- 71, 428/410
• US Class Current: 428/410
• 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 3/087 containing calcium oxide, e.g. common sheet or container glass
• CPC Class Codes: C03C 4/02 for coloured glass
• CPC Class Codes: Y10T 428/315 Surface modified glass [e.g., tempered, strengthened, etc.]

Abstract

Glass comprising, as represented by mole percentage based on the following oxides, from 50 to 75% of SiO₂, from 1 to 15% of Al₂O₃, from 6 to 21% of Na₂O, from 0 to 15% of K₂O, from 0 to 15% of MgO, from 0 to 20% of CaO, from 0 to 21% of ΣRO (wherein R is Mg, Ca, Sr, Ba and/or Zn), from 0 to 5% of ZrO₂, from 1.5 to 6% of Fe₂O₃, and from 0.1 to 1% of Co₃O₄.

Claims

1. Chemically tempered glass comprising, as represented by mole percentage based on the following oxides, from 50 to 75% of SiO₂, from 1 to 15% of Al₂O₃, from 6 to 21% of Na₂O, from 0 to 15% of K₂O, from 0 to 15% of MgO, from 0 to 20% of CaO, from 0 to 21% of Σ

RO (wherein R is Mg, Ca, Sr, Ba and/or Zn), from 0 to 5% of ZrO₂, from 1.5 to 6% of Fe₂O₃, and from 0.1 to 1% of Co₃O₄, and having a compressive stress layer of from 6 to 70 μ

m in a depth direction from the surface.

2. The chemically tempered glass according to claim 1, which comprises from 0 to 15% of SrO, from 0 to 15% of BaO, or from 0 to 15% of ZnO.

3. The chemically tempered glass according to claim 1, wherein the Co₃O₄/Fe₂O₃ ratio is from 0.01 to 0.5.

4. The chemically tempered glass according to claim 1, which comprises from 0.005 to 0.5% of SO₃.

5. The chemically tempered glass according to claim 1, wherein the iron redox is from 10 to 50%.

6. The chemically tempered glass according to claim 1, which has a visible light transmittance of at most 30% at a thickness of 0.5 mm.

7. The chemically tempered glass according to claim 1, wherein when the transmittance at 600 nm is normalized to 1, the relative values of the transmittance at 550 nm and the transmittance at 450 nm are both at least 1.

8. The chemically tempered glass according to claim 1, which has a maximum thickness of at most 2 mm.

9. The chemically tempered glass according to claim 1, which comprises from 3 to 12% of SrO.

10. The chemically tempered glass according to claim 1, which comprises from 3 to 12% of BaO.

11. The chemically tempered glass according to claim 1, which comprises from 3 to 12% of ZnO.

12. The chemically tempered glass according to claim 1, which comprises from 1 to 21% of Σ

RO.

13. The chemically tempered glass according to claim 1, which comprises from 5 to 16% of Σ

RO.