Glass plate for induction cooking device

Patent metadata

Field	Value
Publication number	US-10081568-B2
Application number	US-201314437567-A
Country	US
Kind code	B2
Filing date	Oct 29, 2013
Priority date	Oct 30, 2012
Publication date	Sep 25, 2018
Grant date	Sep 25, 2018

Abstract

The subject matter of the invention is a reinforced glass plate for an induction cooking device, the chemical composition of which comprises the following colorants, in a content which varies within the weight limits defined hereinafter: Fe 2 O 3 (total iron): 0.8% to 1.8%, CoO: 0.02% to 0.06%, Se: 0 to 0.005%, Cr 2 O 3 : 0 to 0.1%. The invention is also directed towards an induction cooking device comprising at least one inductor placed under such a glass plate.

First claim

The invention claimed is:

1. A plate made of strengthened glass, the plate comprising a chemical composition comprising the following colorants, in a content varying within the limits by weight defined below:

Fe 2 O 3 (total iron)
0.8 to 1.8%;

CoO
0.02 to 0.06%;

Se
0 to 0.005%; and

Cr 2 O 3
0 to 0.1%,

wherein the plate does not comprise crystals connected by a residual vitreous phase.

2. The glass plate of claim 1 , wherein a linear thermal expansion coefficient of the glass is at most 50×10 −7 /K.

3. The glass plate of claim 1 , wherein the glass is a lithium aluminosilicate, a borosilicate or an alumino-borosilicate glass.

4. The glass plate of claim 3 , wherein the chemical composition further comprises:
silica SiO 2 in a content by weight ranging from 49 to 75%;
alumina Al 2 O 3 in a content by weight ranging from 15 to 30%; and
lithium oxide Li 2 O in a content by weight ranging from 1 to 8%.

5. The glass plate of claim 4 , wherein the chemical composition comprises the following constituents, varying within the limits by weight defined below:

SiO 2
49-75%; 

Al 2 O 3
15-30%; 

Li 2 O
1-8%;

K 2 O
0-5%;

Na 2 O
0-5%;

ZnO
0-5%;

MgO
0-5%;

CaO
0-5%;

BaO
0-5%;

SrO
0-5%;

TiO 2
0-6%;

ZrO 2
0-5%;

P 2 O 5
    0-10%; and

B 2 O 3
0-5%.

6. The glass plate of claim 1 , wherein the chemical composition further comprises:
silica SiO 2 in a content by weight ranging from 70 to 85%;
boron oxide B 2 O 3 in a content by weight ranging from 8% to 20%; and
at least one alkali-metal oxide, a total content by weight of alkali-metal oxides ranging from 1 to 10%.

7. The glass plate of claim 6 , wherein the glass is a borosilicate glass in which the chemical composition further comprises the following constituents, varying within the limits by weight defined below:

SiO 2
70-85%;

B 2 O 3
 8-16%;

Al 2 O 3
 0-5%;

K 2 O
0-2%; and

Na 2 O
 1-8%.

8. The glass plate of claim 1 , wherein the glass is an alumino-borosilicate glass in which the chemical composition further comprises:
silica SiO 2 in a content by weight ranging from 45% to 68%;
alumina Al 2 O 3 in a content by weight ranging from 8 to 20%;
boron oxide B 2 O 3 in a content by weight ranging from 4% to 18%; and
at least one alkaline-earth oxide selected from the group consisting of MgO, CaO, SrO and BaO, in a total content ranging from 5 to 30%.

9. The glass plate of claim 1 , wherein a content by weight of the Fe 2 O 3 (total iron) varies from 0.9 to 1.7%.

10. The glass plate of claim 1 , wherein a content by weight of the CoO varies from 0.03 to 0.05%.

11. The glass plate of claim 1 , wherein a content by weight of Cr 2 O 3 is zero.

12. The glass plate of claim 1 , wherein a content by weight of the TiO 2 is at most 1%.

13. The glass plate of claim 1 , wherein the glass is thermally strengthened.

14. An induction cooking appliance, comprising at least one inductor placed under the glass plate of claim 1 .

15. The cooking appliance of claim 14 , further comprising at least one device that emits white light.

16. The glass plate of claim 1 , wherein a linear thermal expansion coefficient of the glass is between 30 and 45×10 −7 /K.

17. The glass plate of claim 4 , wherein the chemical composition comprises the following constituents, varying within the limits by weight defined below:

SiO 2
52-75%; 

Al 2 O 3
18-27%; 

Li 2 O
2.5-5.5%;  

K 2 O
0-3%;

Na 2 O
0-3%;

ZnO
0-3.5%;  

MgO
0-3%;

CaO
0-2.5%;  

BaO
0-3.5%;  

SrO
0-2%;

Ti

Assignees

• Eurokera

Inventors

• Plevacova Kamila
• Brunet Edouard
• Lecomte Emmanuel

Classifications

• C03C3/083

  containing aluminium oxide or an iron compound · CPC title

• C03C3/085

  containing an oxide of a divalent metal · CPC title

• C03C3/091 Primary

  containing aluminium · CPC title

• H05B6/1209

  induction cooking plates or the like and devices to be used in combination with them · CPC title

• C03C3/089

  containing boron · CPC title