Method for manufacturing high opacity, durable pigment

摘要

The present invention relates to an improved titanium dioxide pigment that incorporate a dense silica coating and its process for manufacture. The pigment is preferably produced from a titania base from the chloride process in which the manufacturing process comprises the following steps in the order stated: (a) partial or substantial removal of salt from the oxidizer discharge; (b) addition of a dispersant; (c) milling to produce a highly dispersed, highly deagglomerated slurry, followed by dense silica surface treatment. Pigments prepared using the inventive process exhibit optics equivalent to high gloss, high opacity pigments and maintain the durability of the more conventional dense silica treated pigments.