11 ноября, 2015 
Pokraskin All particles in a given pigment are not identical in size; rather, they are a mixture of particles with different sizes. Therefore, pigments are generally evaluated for their mean particle size and particle size distribution by means of the following methods:
• Sieve analysis
• Accelerated sedimentation, such as centrifugal and ultra-centrifugal
• Light attenuation and scattering techniques, such as spectrophoto — metric techniques, light scattering techniques and laser diffraction
• Microscopy, such as using an optical microscope, electron microscope or transmission electron microscope
• Coulter counter
• Surface area measurement (using gas/liquid adsorption)
Each of the above methods has advantages and limitations, but sedimentation methods (using centrifuges) and diffraction techniques are frequently used for the determination of particle size of pigments.
Further details on particle size measurement and basic related terms are in ISO 9276, ASTM D 1366, DIN 53206-1, DIN 66141, DIN 66143, DIN 66144 and DIN 66145.
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