1. Material Explanation

Ceramic is made of clay. After the clay or other inorganic non-metal raw materials are formed and sintered, they are made into ceramics which are used to decorate and protect the walls and floors. Ceramics won’t dissolve in water after they are harden by drying and heating to some certain degree.

The main compositions of ceramic cups are kaolin, clay, chinastone, porcelain clay, blue and white pigment, lime glaze and lime alkaline glaze. Pure kaolin is in dense or loosen piece, white or light gray.Polluted by other impurities, kaolin changes into brown, pink and beige, and it is easy to pinch into powder. After it is roasted, it changes into white. Kaolin is a fine raw material to produce porcelian.

2. Classifications of Ceramics

(1)Classified by sorts. The main circulated ceramics in market are household fine china, household china, ceramic bone china, exquisit household china, household glaze china, ordinary porcelian cooker, fine porcelian cooker. Except ceramic bone china, other ceramics may be classified into superior ones, top quality ones and qualified ones.

(2)Classified by decoration method. Ceramics can be divided into overglaze color, in-glaze decoration, underglaze color, glaze porcelain and white ceramic.

Overglaze color china is to paste or paint the overglaze china pigment on the product surface and bake under 700-850︒. Because the baking temperature doesn’t reach the melting point of glaze, so the pattern won’t dip into glaze but stick on the glaze surface. If you touch the product, you may feel the uneven surface.

The baking temperature of in-glaze decoration is higher than overglaze color china, reaching the melting point of glaze, so the pigment will dip into glaze, after cooling, the pigment will be covered by glaze.Thus, the surface is smooth and even.

Underglaze color is a traditional decoration method in China. The whole decoration is on ware, and the glazed ware will be baked into finished product. Same as in-glaze decoration, the pattern is covered by glaze, and the surface is smooth, and barely has uneven feel.

Glaze china is to add a high temperature toner in pigment in order to make the finished product present a certain color like yellow, blue, green etc. White ceramic refers to the unglazed ceramic.