1 Standard film thickness is still thought of as 50 - 80 µm so anything less than this can be considered thin film. Thicknesses down to 25 µm can be achieved today, however, when you get down to this level, there are already challenges in manufacture as well as in application. For white/light colours, hiding power at such low thickness is the first challenge. Putting enough TiO 2 into the coating to give good opacity needs to be balanced with the ever-increasing cost of this key material. Particle size distribution (psd) is very important too. The average psd of a ...