Particle Size Distribution and Application Properties of Pigmented Media

7 Particle Size Distribution and Application Properties of Pigmented Media 

There are a number of specific cases in which, independent of the application, the tinctorial strength of a product is even more sensitive to the particle size distribution. 

The shade of a product is another parameter which is influenced by the particle size (Sec. 1.6.1.2). This is easy to see by comparing the reflection curves of two Pigment Yellow 83 white reductions in an alkyd-melamine resin system. The electron photomicrographs in Fig. 65 and the particle size distribution histograms in Fig. 66 represent these samples. At equal pigment concentration, curve 1 of the two remission curves in Fig. 67 reflects the behavior of the pigment with the smaller 

Paints behave similarly. Fig. 68 illustrates the color shifts which are observed in Pigment Yellow 1 pastes containing different particle size distributions (Sec. 1.7.1). The colors are identified according to their location on the DIN Color Chart, in which each color is defined by two values, x and y [4]. Increasing amounts of pig- 

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