Vitroceramic plate

Patent metadata

Field	Value
Publication number	US-10017415-B2
Application number	US-201515510529-A
Country	US
Kind code	B2
Filing date	Sep 11, 2015
Priority date	Sep 12, 2014
Publication date	Jul 10, 2018
Grant date	Jul 10, 2018

Abstract

A transparent, colorless and non-scattering glass-ceramic plate of lithium aluminosilicate type and containing crystals of β-quartz structure, the chemical composition of which does not contain oxides of arsenic, of antimony and of neodymium, and includes the following constituents within the limits defined below, expressed as weight percentages: SiO 2 55-75%; Al 2 O 3 12-25%; Li 2 O 2-5%; Na 2 O+K 2 O 0-<2%; Li 2 O+Na 2 O+K 2 O 0-<7%; CaO 0.3-5%; MgO 0-5%; SrO 0-5%; BaO 0.5-10%; CaO+BaO >1%; ZnO 0-5%; TiO 2 ≤1.9%; ZrO 2 ≤3%; TiO 2 +ZrO 2 >3.80%; SnO 2 ≥0.1%; SnO 2 /(SnO 2 +ZrO 2 +TiO 2 )<0.1.

First claim

The invention claimed is:

1. A transparent, colorless and non-scattering glass-ceramic plate of lithium aluminosilicate and containing crystals of β-quartz structure, the chemical composition of which does not contain oxides of arsenic, of antimony and of neodymium, and comprises the following constituents within the limits defined below, expressed as weight percentages:

SiO 2
  55-75%,

Al 2 O 3
  12-25%,

Li 2 O
   2-5%,

Na 2 O + K 2 O
 0-<2%,

Li 2 O + Na 2 O + K 2 O
 0-<7%,

CaO
   0.3-5%,

MgO
   0-5%,

SrO
   0-5%,

BaO
 0.5-10%,

CaO + BaO
   >1%,

ZnO
   0-5%,

TiO 2
 ≤1.9%,

ZrO 2
   ≤3%,

TiO 2 + ZrO 2
 >3.80%,

SnO 2
 ≥0.1%,

SnO 2 /(SnO 2 +
<0.1

ZrO 2 + TiO 2 ).

2. The glass-ceramic plate as claimed in claim 1 , wherein a light transmission factor of the glass-ceramic plate is at least 75%, and the b* color coordinate of the glass-ceramic plate is at most 20.

3. The glass-ceramic plate as claimed in claim 1 , wherein the glass-ceramic has a coefficient of linear thermal expansion of at most 10×10 −7 K −1 between 20 and 700° C.

4. The glass-ceramic plate as claimed in claim 1 , wherein the crystals of β-quartz structure have a size of at most 100 nm.

5. The glass-ceramic plate as claimed in claim 1 , wherein a sum of the TiO 2 and ZrO 2 contents is greater than 4%.

6. The glass-ceramic plate as claimed in claim 1 , wherein the TiO 2 content is at most 1.8%.

7. The glass-ceramic plate as claimed in claim 1 , wherein the SnO 2 content is at least 0.15%.

8. The glass-ceramic plate as claimed in claim 1 , wherein the CaO content is at least 0.8%.

9. A glass plate capable of being converted to a glass-ceramic plate as claimed in claim 1 by a ceramization treatment.

10. A cooking device comprising at least one plate as claimed in claim 1 .

11. A domestic oven door comprising at least one plate as claimed in claim 1 .

12. A fireplace insert comprising at least one plate as claimed in claim 1 .

13. A fire-resistant glazing comprising at least one plate as claimed in claim 1 .

14. A process for obtaining a glass-ceramic plate as claimed in claim 1 , comprising performing a melting step, a forming step, then a ceramization step.

15. The glass-ceramic plate as claimed in claim 1 , comprising, expressed as weight percentages:

SiO 2
  60-70%,

Al 2 O 3
  19-24%,

Li 2 O
   3-4%,

Na 2 O + K 2 O
   0-1%,

Li 2 O + Na 2 O + K 2 O
   0-5%,

CaO
  0.3-5%,

MgO
   0-1%,

SrO
   0-1%,

BaO
   1-5%,

CaO + BaO
   3-5%,

ZnO
   1-2%,

TiO 2
 ≤1.9%,

ZrO 2
   2-3%,

TiO 2 + ZrO 2
 >3.80%,

SnO 2
 ≥0.1%,

SnO 2 /(SnO 2 +
<0.06

ZrO 2 + TiO 2 ).

16. The glass-ceramic plate as claimed in claim 2 , wherein the b* color coordinate of the glass-ceramic plate is at most 15.

17. The domestic oven door as claimed in claim 11 , wherein the plate is the closest to a chamber of said an oven that includes the domestic oven door.

Assignees

• Eurokera

Inventors

• Plevacova Kamila
• Lecomte Emmanuel
• Jousseaume Cécile
• Di Caro Richard

Classifications

• F24C15/10

  Tops, e.g. hot plates; Rings (cover lids or splash guards F24C15/12; spillage trays or grooves F24C15/14) · CPC title

• C03C2209/00

  Compositions specially applicable for the manufacture of vitreous glazes · CPC title

• C03C23/007

  by thermal treatment · CPC title

• C03C10/0027 Primary

  containing SiO2, Al2O3, Li2O as main constituents · CPC title

• C03C8/14

  Glass frit mixtures having non-frit additions, e.g. opacifiers, colorants, mill-additions · CPC title