China Clay or Kaolin is a white burning non plastic clay mineral with the chemical composition Al2Si2O5(OH)4. It is very soft in feeling and finer in particle size. It results from the alterations of feldspars, granite, gneiss and pegmatite rocks by hydrothermal action of aqueous solution. China clay carries minute impurities such as silica, iron, magnesium, titanium, calcium, potassium, sodium oxides, mica, tourmaline, etc. It is white in appearance and mined in lumps forms. The quality of china clay depends much upon the impurities present.
- Highly bright
- Easily dispersed
- Accurate chemical composition
- Withstands high temperature
ApplicationsChina clay is mainly used in ceramics, textiles, and Paper, rubber, paints, cosmetics and pharmaceuticals industries. It is also used in insecticides, white cement manufacturing.
- Used in paints for lending excellent exterior durability and archeological improvement
- Acts as an essential ingredient of oil based and water based paints.
- Used as a coating pigment in the manufacture of coated paper and boards.
- Demanded by the Rubber Industry to improve the impact resistance, tensile strength, hardness and abrasion of rubber.
- Extensively used in PVC wires, inks, adhesives, toothpaste, soaps, etc.
- Ceramic Tiles & other ceramic wares.
- White cement manufacturing.
- Medicines and pharmaceuticals industries.
- White incandescent light bulb
|Parameter (Physical / Chemical)||China Clay||Chemical Analysis|
|Physical properties||SiO2||44 – 55|
|Whiteness||80-95||Al2O3||33 – 39|
|Brightness (ISO)||85-97||TiO2||0.5 ± 0.1%|
|After Fired Brightness||90-98||Fe2O3||1.5 ± 0.2%|
|After Fired Color Shade||Pure White, White, Creamish White||MgO||0.5 ± 0.2%|
|Moisture||< 10 %||CaO||1 ± 0.5%|
|Ph (OF 10% Solution)||6 to 8||K2O||1 ± 0.5%|
|Residue (325#) Calibrated Sieve||<2 %||Na2O||0.5 ± 0.05%|
|Wet To Dry Shrinkage||3 – 4||LOI||< 14%|
|Wet To Fired Shrinkage||10 – 14|
|Green M.O.R (Kg/Cm2)||5 – 6|
|Fired M.O.R (Kg/Cm2)||55 – 57|
|Oil absorption||35-40 %|
|Water absorption||25-35 %|