From
Ceramic Mug Group,According to the usage and firing temperature, ceramic pigments can be divided into overglaze pigments, underglaze pigments and in glaze pigments:
1. Overglaze pigments are used for decoration on the surface of the glaze layer of the calcined ceramic vessels. It contains color group and flux (60-95% in general), and its melting temperature is low. The color firing temperature is low, usually between 800 ~ 850 degree. There are many kinds of pigments on glaze, such as Jiachi, doucha, Daizhe, capsanthin, orange and so on.
2. Underglaze pigment is a kind of pigment used to decorate the green body (green body or plain burning body) without glaze. It is composed of color agent (or color base) and a small amount of diluent (clay, kaolin, green powder, quartz, alumina, etc.). The function of diluent is to dilute tone and control shrinkage. Underglaze pigments are sometimes mixed with more refractory fluxes, such as feldspar or frits of glaze. The color of underglaze pigment is required to be stable at high temperature, not affected by the blank and glaze. The common underglaze pigments are ferruginous red, chrome aluminum red, vanadium zirconium yellow, praseodymium yellow, cobalt chrome green, vanadium black, antimony tin grey and ferrochrome tin brown.
3. Pigment in glaze is a new type of ceramic pigment developed in 1970s. The composition of the flux contains no or less lead, which can withstand higher temperature. After decoration on glaze or utensils, it is calcined under the system of high temperature and fast firing (when it is used for decoration of fine
china sublimation mug manufacturers, the calcination temperature is about 1060 ~ 1100 degree, and the time is about 60 ~ 90min; when it is used for decoration of porcelain, the calcination temperature is about 1100 ~ 1250 degree, and the time is about 90 ~ 100min). In this way, the pigment can penetrate into the inner part of the glaze layer, and the effect similar to the underglaze color will appear. Glaze pigment is also called high temperature fast burning pigment. Ceramic pigments can also be classified according to the mineral phase of pigments.
