Matt and Special Effects Powder Coatings - Paint India 2014 (original) (raw)
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The growth of the powder coating business is affected by the toxicological effects of the raw materials used in the coating formulation and the saturation of the present market for powder coatings, being limited to general metal applications only. This has a strong influence on the long-term research programmes at both raw materials suppliers and powder paint producers. In the last decade of the 20th century, we witness appearance of several new types of toxicologically-safe powder coating systems on the commercial scale. At the same time, there is strong evidence of efforts to penetrate new market fields where powder coatings are not typically used. This includes the markets for automotive clear top coatings, can and coil coatings, coatings for industrial wood, plastics and paper. The new developments in the chemistry of powder coatings are followed by changes and improvements in the production technology for powder coatings as well as developments of new application techniques. This paper summarises the research work on chemistry, production and application technology of powder coatings and tries to extrapolate the tendencies in the years to come in order to predict the achievements and the impacts on the paint industry.
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The coating technology is very commonly applied to modify or improve powders properties. The dry coating is one technology to coat particles without using of organic solvent or water dispersion. Compared to solvent and water based coating, the dry coating method is favourable regarding environmental friendliness, safety and cost. It might be a very suitable coating method in order to coat foods and drugs which are sensitive to organic solvents or water. Dry particle coating, consists in coating relatively large particle size (core material or host) with fine particles (guest). The adhesion of these particles is made using mechano-chemical treatment or using plasticizer. The using of plasticizer is particularly indicated to coat particles that are relatively soft and very sensitive to heat and can be deformed by severe mechanical forces. The object of this work is the study of coating of particles with modified polysaccharides, using pan coater equipment. The mechanism of coating on particles surface and process parameters are being further investigated to be able to obtain a homogeneus coating shell and to reach the desired particle attributes.
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