Paints · Paper · Rubber
Calcined Kaolin
Heat-treated kaolin with higher brightness, opacity, and hardness than raw china clay.
The grade
Calcined kaolin is china clay that has been heat-treated. The reason to buy it is simple: raw kaolin is not bright enough, opaque enough, or hard enough for the line. Paints, paper coatings, cables, rubber, and plastics are the usual homes. A ceramic body that still needs plasticity should stay with hydrous kaolin or a blend.
In the kiln the clay loses combined water, brightness moves up, and the particle hardens. That is what a coating chemist is paying for. It is also why you cannot swap it into a plastic body and expect the same forming behaviour.
Skylark Exports supplies calcined kaolin against the brightness and the mesh your line already uses. Compare a sample. The notes on this page describe the grade family. They are typical, and they are not a certificate of analysis. If you are unsure which clay the coating actually needs, the note on kaolin and calcined kaolin walks through that choice.
What buyers check
- Brightness and opacity above the hydrous kaolin it starts from
- Hardness that raw china clay does not give a coating or a compound
- Low loss on ignition after calcination, so the grade stays stable in process
- A fit for paint, paper coating, cable, rubber, and plastics when raw kaolin falls short
Applications
- Paints and coatings
Coatings use ground quartz, kaolin, and calcined kaolin for mesh, brightness, and opacity in the film.
- Paper
Paper coatings use kaolin for shade and smoothness, and calcined kaolin when opacity has to go further.
- Rubber and plastics
Rubber, plastics, and cable compounds use kaolin, calcined kaolin, and quartz powder as controlled fillers.
Packing
- 25 kg bags, typical export packing, still to confirm
- 50 kg bags, typical export packing, still to confirm
- 1 MT jumbo bags, typical export packing, still to confirm
Questions buyers ask
When does a coating line need calcined kaolin instead of kaolin?
Raw kaolin is the right clay for many ceramic bodies and for some coatings. A coating, cable, rubber, or plastics line that needs more brightness, more opacity, and a harder particle usually moves to calcined kaolin. If raw kaolin already hits your shade and film, calcined is an extra cost you may not need.
What does calcination change?
The clay is heated so combined water leaves and the particles become harder and brighter. Loss on ignition drops. The clay is no longer the plastic forming clay a ceramic body expects. Treat it as a coating and compound grade, not as a substitute for hydrous kaolin in a plastic body.
Which mesh is typical?
Paint, paper coating, and polymer lines are qualified on a particle size. Send the mesh or the curve you already run. This page does not lock a single mesh, and it does not publish a brightness number without your test method.
How is calcined kaolin packed?
Typical export packing is 25 kg bags, 50 kg bags, or 1 MT jumbo bags. What Skylark offers is still to be confirmed. Put packing, quantity, and your destination port on the inquiry.
