31 декабря, 2015 
Pokraskin Pearlescent pigments give rise to a white pearl effect often accompanied by a coloured iridescence. The most important pearlescent pigments consist of thin platelets of mica coated with titanium dioxide which partly reflect and partly transmit incident light. Simultaneous reflection from many layers of oriented platelets creates the sense of depth which is characteristic of pearlescent lustre and, where the particles are of an appropriate thickness, colours are produced by interference phenomena. Pearlescent pigments are used in automotive finishes, plastics and cosmetics.
Daylight fluorescent pigments consist essentially of fluorescent dyes dissolved in a transparent and colourless polymer. The resulting solid solutions are then ground to a fine particle size for incorporation as pigments into paints, printing inks or plastics. In these application media, the pigments in daylight give rise to colours which possess a remarkable vivid brilliance as a result of the extra glow of fluorescent light. The applications of daylight fluorescent pigments are generally associated with their extremely high visibility and their ability to attract attention such as in advertising and in the field of safety. Fluorescent pigments are mostly based on a toluenesulfonamide-melamine-formaldehyde resin matrix. The fluorescent dyes most commonly used in the pigments are rhodamines (Chapter 6) in the red to violet shade range, and aminonaph — thalimides and coumarins (Chapter 4) in the yellow shade range.
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