This document specifies a method for the determination of the particle size distribution of coating powders by sieve analysis. Particle size distributions with a maximum of less than 100 µm is determined by laser diffraction, ISO 8130‑13. This method is used especially for determining the oversize material or for the presence of contamination and can be used as a quality control procedure ("go"/"no go" test) by checking the amount retained on a single sieve.
The following particle sizes are typical for coating powders, however the particle size can deviate depending on the application:
— thin-film technology: 1 µm to 63 µm;
— electrostatic coating: 10 µm to 200 µm;
— fluidizing-bed method: 100 µm and above.
NOTE Sieves with a mesh size smaller than 32 µm are not practical and are likely to become blind during use.