What is Glazes?
Glaze contains glass composition, when firing to form a non-porous glass layer.
They are usually also suitable for Bisque pottery, but occasionally they are also suitable for green porcelain if they are single fire glaze.
Underglaze and overglaze composition
In this section, I will be able to examine the similarities and differences between the composition of underglaze and glaze.
While single-fire glazing is an option, most of the time, glazing is applied to porcelain. Part of the reason for this is that Bisque pottery is usually porous and can absorb water from the glaze. As a result, the stone is coated with glaze.
In contrast, many modern underglaze vessels are designed for either celadon or celadon. In fact, underglazes are often used on wet clay, leather hard clay, bone dry clay or bisque ware.
The time of using underglaze coating depends on the type of underglaze coating used. for instance. If the underglaze may be colored clay, it is usually used for wet clay. An underglaze pencil must be used in Bisque pottery. If a pencil is used on unfired clay, the surface of the work may be damaged.
Another factor affecting the use of underglaze coatings is the water content involved. For example, underglaze coatings are usually used for celadon. However, the water in the underglaze coating will soften the clay in the pottery and affect its shape or design. Therefore, it is usually easier to use wet underglaze porcelain.
Having said that, if you dip the underglaze pigment in a transparent glaze, the color in the underglaze pigment will disappear. So, there’s also the argument that the underglaze is applied to the greenware, fired, and then glazed.
Overglaze and underglaze are two different ways to decorate porcelain. Each method has its advantages and disadvantages, but each method gives porcelain a completely different way of expression. Whether you use one or the opposite depends on what kind of finished porcelain you want.
It’s all about the color!
This is its point when it comes to overglaze and underglaze. The difference between the two methods is expressed visually by the color of the finished porcelain. The color selection range of overglaze process is wider than that of underglaze process. the rationale for this is often chemical. It’s just a matter of breaking down the colours at different temperatures, with underglaze colours much hotter than overglaze colours. This is why you will find more colors in overglaze porcelain than underglaze porcelain.
In fact, the reason blue is so widely used in porcelain is that it can withstand the best temperatures, especially underglaze colors, which are widely used in Danish porcelain. Have you ever wondered why there are so few colors in the Royal statue of Copenhagen and the statue of binglundar? This is usually because they are underglaze statues, so there are only a few colors to choose from.
Why two methods?
The important difference between overglaze and underglaze is when to use paint. In the case of overglaze, burn the glass from the China and then paint it. When using underglaze paint, first coat the paint on unglazed porcelain, and then coat the glaze on the paint. This is underglaze. The paint is under the glaze. The glaze on the porcelain may be a layer of glass covering the underside of the block. The glaze is burned at a really heat of quite 2372°F. This temperature will dissolve most types of paint, but on the other hand, the paint will be permanently protected under the glaze. After glazing, the overglaze burns only at 1472°F, indicating that several paints are often used. Especially. Red and gold should not be used under the glaze.
After glazing, the paint needs to be burned further, which will increase the value. Therefore, overglaze is additionally often costlier than underglaze.
Therefore, this is a trade-off, the formation of the choice for porcelain overglaze or underglaze color idea. Is the color choice or price the most important factor in decoration?
Overglaze decoration is usually used for more elaborate and complex statues, because this method is most suitable for this situation, because the color here is not affected by warmth as underglaze decoration.