Soluble dyes plastics applications

Fat- and oil-soluble dyes are used on a large scale in a wide variety of industrial sectors. The main fields of application are the coloration of products in the mineral oil and plastics industries, as well as of wax products (e.g., candles, shoe polishes, floor polishes). 

Dyes. Dyes similar to pigments are listed according to their class, generic name, and Color Index (Cl) name and number. The dyes are essential without them, many transparent effects in plastics could not be achieved. Dyes are soluble in plastic, and therefore more transparent by nature than pigments. Dyes are known for poor lightfastness in tinted application. This is not as great a concern in masstone or transparent parts as failure occurs on the surface, and the color beneath is unaffected. 

Since there are no solvent-soluble FD C colors, FD C lakes have proven particularly valuable for coloring water-repelling foods such as fats, gums, waxes, and oils, and for coloring food-packaging materials including lacquers, containers, plastic films, and inks from which soluble dyes would be quickly leached. Similarly useful applications have been found for D C and Ext. D C lakes in their respective areas of application. 

For commercial printing onto nonporous, hydrophobic materials such as plastics, metals, and glass, rapidly drying solvent inks which adhere to these substrates are needed. A typical solvent for these applications is methyl ethyl ketone (MEK). However, alternative alcoholic solvents tike ethanol and N-propanol have been introduced for ecological and safety reasons. The predominant color for industrial marking is black, and solvent soluble 2 1 azo chromium(m) complex, polyazo, Nigrosine, and sulfur dyes are used. Typical formulation of an... 

Colour is introduced into these materials and applications using substances known as dyes and pigments, or collectively as colorants. The essential difference between these two colorant types is that dyes are soluble coloured compounds which are applied mainly to textile materials from solution in water, whereas pigments are insoluble compounds incorporated by a dispersion process into products such as paints, printing inks and plastics. The reader is directed to Chapter 2 of this book for a more detailed discussion of the distinction between dyes and pigments as colouring materials. 

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