Enamel composition, method for preparing enamel composition, and cooking appliance

Patent metadata

Field	Value
Publication number	US-11274060-B2
Application number	US-202016795923-A
Country	US
Kind code	B2
Filing date	Feb 20, 2020
Priority date	Feb 22, 2019
Publication date	Mar 15, 2022
Grant date	Mar 15, 2022

Abstract

An enamel composition, a method for preparing an enamel composition, and a cooking appliance are provided. The enamel composition may include 20 to 50% by weight of silicon dioxide (SiO 2 ), 7 to 12% by weight of boron oxide (B 2 O 3 ), one or more of lithium superoxide (Li 2 O), sodium oxide (Na 2 O), or potassium oxide (K 2 O), and 10 to 20% by weight of sodium fluoride (NaF), 1 to 10% by weight of zinc oxide (ZnO), and one or more of molybdenum oxide (MoO 3 ), bismuth oxide (Bi 2 O 3 ), or cerium dioxide (CeO 2 ), and 10 to 40% by weight of titanium dioxide (TiO 2 ). With such an enamel composition, cleaning is possible in a heating condition of a relatively low temperature and without a soaking process using water.

First claim

What is claimed is:

1. An enamel composition, comprising:
20 to 50% by weight of silicon dioxide (SiO 2 );
7 to 12% by weight of boron oxide (B 2 O 3 );
one or more of lithium superoxide (Li 2 O), sodium oxide (Na 2 O), or potassium oxide (K 2 O), and 10 to 20% by weight of sodium fluoride (NaF);
1 to 10% by weight of zinc oxide (ZnO); and
one or more of molybdenum oxide (MoO 3 ), bismuth oxide (Bi 2 O 3 ), or cerium dioxide (CeO 2 ), and 10 to 40% by weight of titanium dioxide (TiO 2 ).

2. The enamel composition of claim 1 , wherein the MoO 3 is 3 to 10% by weight.

3. The enamel composition of claim 1 , wherein the TiO 2 is 10 to 15% by weight.

4. The enamel composition of claim 1 , wherein the TiO 2 is 10 to 15% by weight.

5. A cooking appliance, comprising:
a cavity in which a cooking space is formed;
a door that selectively opens and closes the cooking space;
at least one heating source that provides heat to the cooking space;
a buffer layer coated on an inner surface of the cavity or an inner surface of the door; and
a coating layer coated on the buffer layer and formed using the enamel composition according to claim 1 .

6. A method for preparing an enamel composition, comprising:
providing materials for the enamel composition, the materials comprising:
20 to 50% by weight of silicon dioxide (SiO 2 );
7 to 12% by weight of boron oxide (B 2 O 3 );
one or more of lithium superoxide (Li 2 O), sodium oxide (Na 2 O), or potassium oxide (K 2 O) and 10 to 20% by weight of sodium fluoride (NaF);
1 to 10% by weight of zinc oxide (ZnO); and
one or more of molybdenum oxide (MoO 3 ), bismuth oxide (Bi 2 O 3 ), or cerium dioxide (CeO 2 ), and 10 to 40% by weight of titanium dioxide (TiO 2 );

melting the materials; and
quenching the melted materials to form the enamel composition.

7. The method of claim 6 , wherein the MoO 3 is 3 to 10% by weight.

8. The method of claim 6 , wherein the TiO 2 is 10 to 15% by weight.

9. A cooking appliance, comprising:
a cavity in which a cooking space is formed;
a door that selectively opens and closes the cooking space;
at least one heating source that provides heat to the cooking space;
a buffer layer coated on an inner surface of the cavity or an inner surface of the door; and
a coating layer coated on the buffer layer and formed using the method for preparing the enamel composition according to claim 6 .

10. The method in claim 6 , wherein the melting of the materials includes melting the materials at about 1,200 to 1,400° C. for about one to two hours.

11. The method in claim 10 , wherein the melting of the materials includes melting the materials at about 1,300° C. for about 1.5 hours.

12. The method of claim 6 , further comprising:
mixing the materials for about 3 hours before melting the materials.

13. The method of claim 6 , wherein the quenching of the melted material includes quenching the melted materials using a quenching roller.

14. The method of claim 6 , further comprising:
applying the enamel composition to at least one of an inner surface of a cavity of a cooking appliance or an inner surface a door of the cooking appliance.

15. The method of claim 14 , wherein the applying of the enamel composition includes applying the enamel composition by a dry process that includes dispersing the quenched materials for the enamel composition in an organic binder, milling the quenched materials for the enamel composition and the organic binder to prepare a frit, and applying the frit to the at least one of the inner surface of the cavity of the cooking appliance or the inner surface the door of the cooking appliance.

16. The method of claim 14 , wherein the applying of the enamel composition includes applying the enamel composition by a wet process that includes dispersing the quenched materials for the enamel composition in water and a pigment, milling the materials for the enamel composition, water, and the pigment to prepare a frit, and applying the frit to the at least one of the inner surface of the cavity of the cooking appliance or the inner surface the door of the cooking appliance.

17. The method of claim 14 , wherein the applying of the enamel composition includes:
spraying a frit that includes the quenched materials for the enamel composition to the at least one of the inner surface of the cavity of the cooking appliance or the inner surface the door of the cooking appliance; and
firing the sprayed frit.

18. The method of claim 17 , wherein the spraying of the frit includes spraying about 300 g/m 2 of the frit onto a steel sheet substrate.

19. The method of 17 , wherein the spraying of the frit includes directly applying a single layer of the frit onto a steel sheet substrate without using an interposing buffer layer.

20. The method of claim 17 , wherein the frit is applied to form a coating layer having a thickness of about 80 to 250 μm, and the frit is fired at about 600 to 900° C. for about 100 to 450 seconds.

Assignees

• Lg Electronics Inc

Inventors

• Choi Suyeon
• Kim Young Seok

Classifications

• C03C2207/02

  containing ingredients for securing a good bond between the vitrified enamel and the metal · CPC title

• C03C8/04 Primary

  containing zinc · CPC title

• C03C8/20

  containing titanium compounds; containing zirconium compounds · CPC title

• C23D5/04

  by dry methods · CPC title

• C03C8/02 Primary

  Frit compositions, i.e. in a powdered or comminuted form · CPC title