The chloride process reacts titanium ore with chlorine gas at high temperature to produce highly pure TiCl₄, which is then oxidised to TiO2. This produces a more uniform particle size distribution, higher purity, better brightness, superior UV resistance, and lower environmental impact vs the sulphate process. Sulphate grade TiO2 is produced by digesting titanium ore with sulphuric acid — it is lower cost and still widely used in standard paints, paper, and plastics, but has lower whiteness, more variable particle morphology, and slightly less durability under UV exposure. For GCC exterior architectural applications and industrial specifications requiring maximum performance, chloride grade is the standard choice.