Bone china is a kind of soft ceramics, which is suitable for making tableware, tea set, coffee set, display porcelain and ceramic gifts.
Bone china is a kind of porcelain based on calcium phosphate. This kind of porcelain is a kind of "calcium phosphate kaolin quartz feldspar" system porcelain with calcium phosphate as solvent, sometimes with other ingredients. Bone china is generally divided into two firing: the first is plain firing, the temperature is 1200 ℃ - 1300 ℃; the second is glaze firing, the temperature is 900 ℃ - 1160 ℃.
After firing, the porcelain is mainly composed of cristobalite, anorthite, mullite and glass phase. Porcelain has high whiteness, high transparency, soft porcelain and soft luster.
The above brief introduction is the basic knowledge you need to understand before you customize ceramics. What's the difference between Bone China and new bone china (that is, what people usually call fake Bone China)?
1、 Bone china is produced in Tangshan, Hebei Province. New bone china is produced in Zibo, Shandong Province, and is developed by the Institute of silicate of Shandong Province.
2、 The difference of composition: the bone powder content of Bone China refers to the content of natural material "tricalcium phosphate" produced in animal bone after calcination. The "tricalcium phosphate" of new bone china is artificially synthesized.
3、 The difference of bone powder: Bone China has added more than 40-25% animal bone powder; new bone china has no natural ingredients of bone powder, only uses the chemical "tricalcium phosphate".
4、 The difference of manufacturing methods: Bone China is divided into two steps: plain firing and glaze firing; new bone china is a one-time firing process.
5、 The difference of lead proportion: Bone China generally has low aluminum content, which is mainly due to the use of aluminum free frit in secondary firing; the high aluminum content of new bone china is the use of aluminum frit.
6、 Color differentiation: the color of Bone China is natural milk white, because it contains high bone content, Bone China with low bone content turns yellow, and the lower it is, the more yellow. New bone china is a kind of chemical material instead of bone powder, adding a certain amount of whitening agent, so its texture is like white porcelain.
7、 The difference of sound: the crisp "Dang" sound of Bone China has echo, and the sound is longer. The higher the grade Bone China, the longer the echo; the dull "Ding" voice of new bone china basically has no echo.
8、 The difference in weight: Bone China is light; new bone china is heavy; white porcelain is the heaviest.
9、 The difference of fetal quality: Bone China is thin; new bone china is thick.
10、 The difference of appearance: Bone China has small deformation (because of secondary firing), the glaze gloss is balanced, bright and without glaze mark; the brightness of new bone china is low, and there are obvious glaze flow marks on the glaze surface.
11、 Transparency comparison: Bone China because of its thin matrix, light transmission effect is more obvious; new bone china is less transparent than bone china, because its carcass is thicker.
12、 The differentiation of types: because Bone China contains bone powder, its viscosity is relatively low, and it is difficult to burn a complex shape; new bone china is added with chemicals, so clay can be added with other hard raw materials, so the modeling difficulty can be increased.
13、 Bone China, new bone china, white porcelain, etc., have no principle comparable degree, can be their own good.
Therefore, when you choose to make to order ceramics, do it according to your needs. Here is just to give you a brief introduction, the general oxidation fired ceramics for soft porcelain, Jingdezhen belongs to redox firing, belongs to hard ceramics.