Isoindoline Pigments properties

The properties of isoindoline pigments depend strongly on their chemical stmcture as well as on particle size and shape. The influence of the physical properties of the pigments on the color behavior is more pronounced for isoindoline pigments than for other pigment groups, e.g. copper phthalocyanines. 

Table 14—5 lists typical properties of commercially available isoindoline pigments. Table 14-S Typical properties of isoindoline pigments.

Only after o-phthalodinitrile became available in high purity on an industrial scale from BASF the importance of these pigments was recognized. By improving the methods of synthesis and finishing it became possible to produce pigments with brilliant hues and better fastness properties. In 1973 BASF released the first isoindoline pigment into the market Lithol Fast Yellow 1840 (P.Y. 139). At the same time several other companies (Bayer, Ciba, Dainippon Ink) published novel isoindoline structures [8- 11]. 

To obtain the necessary fastness properties, high-quality pigments are generally used for security printing. The range of suitable products covers disazo, disazo condensation, benzimidazolone, naphthol AS, isoindolin, perinone, anthanthrone, dioxazine and quinacridone pigments. 

This isoindoline nickel complex pigment is mainly recommended for the coloration of metallics and effect coatings, especially for water based systems. P.R.271 affords yellowish to medium red shades, providing a bright flop in metallics. Alkyd/melamine resin systems may safely be overcoated and withstand exposure of 140°C for 30 minutes. The flow properties of P.R.271 in these systems and in polyester cellulose acetobutyrate base coat systems are good, but there is a certain tendency to flocculate. 

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