METHOD OF PREPARING FINE CRYSTALLINE CORUNDUM Russian patent published in 2001 - IPC

FIELD: synthesis of inorganic materials, more particular manufacture of light-translucent ceramic material and leucosapphire. SUBSTANCE: thermocouple treatment of aluminium hydroxide is carried out at temperatures from 380 to 420 C and pressures from 50 to 300 atm in the presence of lower saturated alcohols methyl, ethyl, propyl or butyl in amount of 0.06-1 wt % with respect to weight of aluminium hydroxide, or with carbamide additive in amount of 0.05- 0.5 wt % with respect to weight of aluminium hydroxide. The resulting corundum samples correspond to optical class of crystals with respect to purity and are useful for facing monocrystals o leucosapphire and light-translucent ceramic material. EFFECT: pure fine crystalline corundum comprising total amount of 12 elements. 2 ex, 1 tbl