For the color, paint and coating industry, these nano-materials are of particolar interest, as by the addition of nano-sized particles may be prepared paints, varnishes and coatings with special decorative and functional properties. Color and gloss characteristics are numbered among the decorative aspects; conductivity, microbial inacti-vation or antistatic properties are numbered to the functional aspects. By addition of nanoparticles, also the protective functions of paints and coatings, such as scratch resistance and UV stability can be improved. In the production of novel color and coating formulations, special nano-sized metal oxides, such as T1O2 and ZnO or alumina, ceria, silica, and nano-sized pigments, have been proven to be extremely promising components. Conventional devices such as high s-hear or shear mixer, high-pressure homogenizers or colloid and disk mills do not deliver sufficient power to separate nanomaterial into its individual particles. Particularly for substances in the range of a few nanometers to a few micrometers, the use of high power ultrasound have been proven as a highly efficient and effective means to destroy the agglomerates, aggregates and even primary particles. During the preparation of highly concentrated batches, through the liquid jets, generated by ultrasonic cavitation, interparticle collision is caused. These particles collide with each other at speeds of up to 400 mph. Due to the high intensity interparticular collision, the van der Waals forces in agglomerates and even in the primary particles becomes broken.
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