Heavy metal toxins mainly come from pigments in glazes. Lead compounds in glazed ceramics can be leached by acid. When food comes into contact with pigments, lead may be leached by organic acids in food. Due to the diversification of ceramic color painting or the use of stickers, it will be harmful or discolored if it is used for a long time or is too acidic, but it will not protect the underglaze color and glaze surface.
Of course, if the glaze color design is reasonable and the barbecue process is proper, lead can be avoided from exceeding the standard. If the ceramic products contain harmful components, they may overflow at the high temperature of 600℃ ~ 800℃, so when people use the microwave oven, it is best to put them in a white tire bowl or an underglaze colored bowl. In contrast, the underglaze and white porcelain on the market at present do not contain lead and are relatively safe.
How to see if the tableware is underglaze?
1, see process.
Under-glaze color is to directly paste decal paper or hand-painted patterns on the porcelain blank, then glaze the decorated blank and fire it in the kiln. Because of the temperature, the color lines will sink under the glaze, forming underglaze color. The underglaze color ceramic tableware is safer, because the pigment is covered by the glaze, there will be no heavy metal precipitation, and it is safer to eat.
2. Look at this color
Glazed ceramic tableware is generally bright in color and rich in patterns; Ceramic tableware with underglaze color is softer and simpler than underglaze color, and its color performance is average, not as magnificent as underglaze color. The representatives of underglaze color are blue and white porcelain, underglaze color and underglaze red.
Step 3 touch your hand
The pattern of glaze color is on the top of glaze, and you will feel the pattern when you touch it with your hands; The pattern of underglaze color is under glaze, and the surface of tableware is smooth, and it feels smooth and flat by hand, without any concave and convex feeling.
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