Abstract:
The present invention relates to a TiO2 pigment coated sequentially in a wet treatment process with hydrous silica and hydrous alumina both in the presence of citric acid wherein the resulting pigment is coated with from 1 to 4% amorphous alumina based on the weight of the untreated TiO2; from 3 to 6% silica glass based on the weight of the untreated TiO2.
Abstract:
The present invention relates to a TiO2 pigment coated sequentially in a wet treatment process with hydrous silica and hydrous alumina both in the presence of citric acid wherein the resulting pigment is coated with from 1 to 4% amorphous alumina based on the weight of the untreated TiO2; from 3 to 6% silica glass based on the weight of the untreated TiO2.
Abstract:
A process is provided to prepare durable, high gloss titanium dioxide pigments by a continuous wet treatment process which involves curing of a silica coating at pH of between 7.0 and 8.5. Pigment prepared in this fashion is substantially free from Al(OH).sub.3 impurities and has excellent performance properties in high quality latex paint formulations.