Bone China takes animal bone charcoal, clay, feldspar and quartz as basic raw materials. The most commonly used are the bones of cattle, sheep, pigs and other animals. Britons believe that calf bone aged 2-4 is the best bone porcelain. Although sheep bone has good plasticity and is easy to form, its whiteness is not as good as cow bone. Cow bone is the best raw material, followed by sheep bone and pig bone. So, why is Bone China advertising cup an aristocratic cup in porcelain?
With good raw materials, we need better technology, otherwise, it will be wasted. When the content of bone meal reaches a certain proportion, the quality of porcelain will be greatly improved, which is mainly reflected in the gloss and smoothness of utensils. However, if the content exceeds a certain proportion, the composition of clay will be relatively reduced, and the porcelain will become too soft, which is easier to crack in the manufacturing process. It requires higher technology in molding, which increases the difficulty of firing, so it is more precious.
The formed bone china was sintered at 1250 ℃. In the sintering process, the finished product will shrink by 20% (generally porcelain shrinks by 7%), so the shape is easy to deform. Plates, bowls, etc., It must be placed on a special pot to sinter for a long time. Then check the shape, size the surface, spray the glaze with the sprayer, and put it in the kiln for 1150 degrees.
The general coloring method is to paste transfer paper on the white finished product and burn it at 800 ℃. Manual coloring takes time, but the texture of the picture is more flexible.
4. Health and environmental protection
Bone China advertising cup is not only beautiful and exquisite, but also more healthy and environmental protection. Ordinary porcelain products are corroded by acid and alkali in daily use, and trace metals will overflow, which will affect human health over time. But bone china doesn't contain lead or cadmium. Overglaze and underglaze bone porcelain are not only lead-free and cadmium free, but also the flower surface is not easy to wear off. It is suitable for dishwashers, disinfection cabinets and steamers. It is a well deserved green and healthy ceramic.