Organic coatings are often pigmented with titanium dioxide in order to produce opacity. However, the presence of titanium dioxide at the surface of the coating can affect its microroughness, which will influence properties such as specular gloss and metal marking. In addition, titanium dioxide pigment is photoactive, which means that during weathering, it will contribute towards the breakdown of the organic binder, and therefore the surface roughness of the coating will increase with exposure time. In order to minimize the effect of titanium dioxide on the surface roughness of a coating, it is important to ensure that the correct grade of pigment is used, and that maximum dispersion is obtained.