China Clay falls under Kaolinite group of clays. It is naturally occurring "Hydrated Aluminum Silicate" having the usual compositions Al
2O
3 2SiO
2 2H
2O. Grit is the most undesirable impurity in China Clay. The grading of the material is primarily done on the basis of the whiteness and grit content. The important properties of China Clay are that is has good plasticity, does not swell in water, withstand high temperature (upto 1300
0C and even above) and is a non-conductor of electricity.
The various grades of China Clay available are: Regular Fine
Micro Fine
Ultra FineTypical Applications: Surface Coatings (Paint) IndustryChina Clay due to its lamellar structure imparts toughness to coatings and tends to reinforce the films. It settles slowly in water and having low solubility in water, its is commonly used in water based paints. Due to its low solubility in the aqueous phase and its ability to impart good brushing and leveling characteristics, it is mainly used in Latex paints.
Rubber IndustryGrit free
China Clay having low bulk density, possessing reinforcing properties, is used as a filler.
Other usesIt is also used in large quantities in the manufacture of Porcelain, China ware, Crockery, Electrical Insulator, paper and Textile Industry.