Hiding power, of pigment

Hiding power of pigment in paint can be measured by refiectometry without the use of standard. It is calculated from the determined values of reflectivity and the scattering coefficient. 

There are many properties of particulate systems other than those relevant to solid-liquid separation, which depend strongly on particle size the activity of dmgs, the setting time of cement, and the hiding power of pigments, to name just a few. 

Manufacturing processes afford azo pigments with, for instance, certain defined physical forms. Thermal treatment usually increases the particle size, reduces the tinctorial strength, and may improve the hiding power of a pigment. Reversal of... 

According to ASTM D 2805-70, the hiding power of a layer is characterized by the ratio of the Y values (as defined in the CIE color system) over a black and a white patch of substrate. If this ratio is larger than 0.98, the layer is referred to as hiding. This criterion occasionally fails if applied to brightly colored pigments. 

There are several techniques which determine the hiding power of a pigmented medium for practical application. Colored systems are typically tested by measuring their ability to entirely cover up a standard black and white checkerboard substrate. Parameters used as variables are the pigment concentration and/or the... 

The recent isoindolinone pigment is already being withdrawn from the market. The commercially available grade had a coarse particle size and thus provided good hiding power. The pigment was recommended for use in various types of industrial paints, including automotive finishes. 

Refraction, R0, which is related to the hiding power of a pigment, is equal to the square of the differences in the n values of the pigment and the polymer, as shown by Fresnel s law where , and nt are the refractive indices of the pigment and the polymer. 

Figure 11. Determination of the hiding power of a yellow iron oxide pigment...

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