In heat ATH (aluminium hydroxide or alumina trihydrate) decomposition begins at around 200°C. At first the hydrate loses two water molecules. The reaction is endothermic, so surrounding heat is consumed, slowing fire propagation. The released water reacts as a smoke suppressor.
The last water molecule is released at around 600°C.
ATH is used in a number of applications as a filler :
- Synthetic latex in the carpet backing
- Unsaturated polyester in the Sheet Moulding Compounds & Bulk Moulding Compounds.
Depending on the customer’s process, hydrates with different particle size distributions are used.
Coarse alumina hydrate
Aluminium trihydroxide (ATH) is produced by the Bayer Process in Gardanne. These ATH grades are used for the production of a variety of aluminium salts and in glass production.
Fine alumina hydrate
Aluminium trihydroxide (ATH) produced by the Gardanne Bayer process is subject to controlled grinding to obtain a range of particle size distributions and low viscosity grades.