Porcelain enamel compositions and coatings made therefrom
A porcelain enamel composition may include a glass component including: at least one alkali oxide in an amount ranging from about 6 to 21 wt %, SiO 2 in an amount ranging from about 20 to 50 wt %, ZnO in an amount ranging from about 0.1 to 10 wt %, Al 2 O 3 in an amount ranging from about 5 to 20 wt %, B 2 O 3 in an amount ranging from about 0.1 to 20 wt %, and P 2 O 5 in an amount ranging from about 5 to 30 wt %, all weight percentages expressed relative to the enamel composition. Methods of using such compositions and formed products are also described.
1. A porcelain enamel composition, comprising:
a glass component including:
at least one alkali oxide in an amount ranging from about 6 to 21 wt %,
SiO 2 in an amount ranging from about 20 to 50 wt %,
ZnO in an amount ranging from about 1.5 to 10 wt %,
Al 2 O 3 in an amount ranging from about 5 to 20 wt %,
F in an amount ranging from greater than 0 to 10 wt %,
B 2 O 3 in an amount ranging from about 0.1 to 20 wt %, and
P 2 O 5 in an amount ranging from about 5 to 30 wt %, and
wherein the porcelain enamel composition is substantially free of BaO,
all weight percentages expressed relative to the enamel composition.
2. The porcelain enamel composition of claim 1 , wherein the at least one alkali oxide comprises Na 2 O in an amount ranging from 5-20 wt % and K 2 O in an amount ranging from about 1 to 15 wt %.
3. The porcelain enamel composition of claim 2 , further comprising Li 2 O in an amount ranging from greater than 0 to 7 wt %.
4. The porcelain enamel composition of claim 1 , further comprising at least one of MnO, CoO, NiO, Fe 2 O 3 or CuO.
5. The porcelain enamel composition of claim 4 , wherein, when present: MnO is present in an amount ranging from greater than 0 to 5 wt %, CoO is present in an amount ranging from greater than 0 to 8 wt %, NiO is present in an amount ranging from greater than 0 to 5 wt %, Fe 2 O 3 is present in an amount ranging from greater than 0 to 8 wt %, and/or CuO is present in an amount ranging from greater than 0 to 5 wt %.
6. The porcelain enamel composition of claim 1 , wherein a total combined amount of Al 2 O 3 , SiO 2 , P 2 O 5 , and ZnO ranges from about 50 to about 75 wt % of the porcelain enamel composition.
7. The porcelain enamel composition of claim 1 , wherein the glass component further includes TiO 2 in an amount ranging from greater than 0 to 8 wt %.
8. The porcelain enamel composition of claim 1 , wherein the glass component further includes ZrO 2 in an amount ranging from greater than 0 to about 15 wt % of the porcelain enamel composition.
9. The porcelain enamel composition of claim 1 , wherein the glass component has alkaline earth oxides in an amount of no more than 3 wt % of the porcelain enamel composition.
10. A method of forming a porcelain enamel coating on a substrate, comprising:
depositing a layer of the porcelain enamel composition of claim 1 on the substrate; and
firing the layer to thereby form a porcelain enamel coating on the substrate.
11. The method of claim 10 , wherein the substrate comprises a ground coat layer thereon such that the layer of the porcelain enamel composition is deposited on the ground coat layer.
12. The method of claim 11 , wherein the ground coat layer and layer of porcelain enamel composition are fired in a single step.
13. The method of claim 10 , wherein the porcelain enamel composition is deposited as a dry powder.
14. The method of claim 10 , wherein the firing occurs at a temperature ranging from about 770 to 900° C.
15. A method of cleaning food residue from a cooking surface comprising a porcelain enamel coating formed from the porcelain enamel composition of claim 1 , comprising:
heating the cooking surface to a temperature of less than about 250° C. in the presence of water vapor or liquid water; and
wiping the food residue off the cooking surface without application of a caustic cleaning agent.
16. The porcelain enamel composition of claim 1 , wherein MnO is present in an amount ranging from 0.1 to 5 wt %.
17. The porcelain enamel composition of claim 1 , wherein the at least one alkali oxide comprises Na 2 O in an amount ranging from 10-15 wt % and K 2 O in an amount ranging from about 5 to 14 wt %.
18. A porcelain enamel composition, comprising:
a glass component including:
at least one alkali oxide in an amount ranging from about 6 to 21 wt %,
SiO 2 in an amount ranging from about 20 to 50 wt %,
ZnO in an amount ranging from about 1.5 to 10 wt %,
Li 2 O in an amount ranging from greater than 0 to 7 wt %,
Al 2 O 3 in an amount ranging from about 5 to 20 wt %,
B 2 O 3 in an amount ranging from about 0.1 to 20 wt %, and
P 2 O 5 in an amount ranging from about 5 to 30 wt %,
wherein the porcelain enamel composition is substantially free of BaO, and
wherein the at least one alkali oxide comprises Na 2 O in an amount ranging from 5-20 wt % and K 2 O in an amount ranging from about 1 to 15 wt %,
all weight percentages expressed relative to the enamel composition.
19. A porcelain enamel composition, comprising:
a glass component including:
at least one alkali oxide in an amount ranging from about 6 to 21 wt %,
SiO 2 in an amount ranging from about 20 to 50 wt %,
ZnO in an amount ranging from about 1.5 to 10 wt %,
Al 2 O 3 in an amount ranging from about 5 to 20 wt %,
ZrO 2 in an amount ranging from greater than 0 to about 15 wt %,
B 2 O 3 in an amount ranging from about 0.1 to 20 wt %, and
P 2 O 5 in an amount ranging from about 5 to 30 wt %,
wherein the porcelain enamel composition is substantially free of BaO,
all weight percentages expressed relative to the enamel composition.
20. A porcelain enamel composition, comprising:
a glass component including:
at least one alkali oxide in an amount ranging from about 6 to 21 wt %,
SiO 2 in an amount ranging from about 20 to 50 wt %,
ZnO in an amount ranging from about 1.5 to 10 wt %,
Al 2 O 3 in an amount ranging from about 5 to 20 wt %,
B 2 O 3 in an amount ranging from about 0.1 to 20 wt %, and
P 2 O 5 in an amount ranging from about 5 to 30 wt %,
wherein the porcelain enamel composition is substantially free of BaO, and
wherein the glass component has alkaline earth oxides in an amount of no more than 3 wt % of the porcelain enamel composition,
all weight percentages expressed relative to the enamel composition.