Pigments tinting strength

Hiding power and tinting strength of a pigment also depend on concentration in the organic matrix. The concentration is usually expressed as the pigment volume concentration ... 

Low Tinting Strength - The zinc borate has a refractive index similar to most organic polymers, which results in the retention of considerable translucency. This provides for easy visual inspection of the finished products and allows the use of lower pigment loadings in formulations requiring deep shades. 

Tinting, of paint, 18 66 Tinting strength, of inorganic pigments, 19 381... 

Table 19.2 Hiding Power and Tinting Strength of Pigments...

Pigment Hiding Power (m /kg) Index of Refraction Tinting Strength... 

Like the natural iron oxide pigments, the synthetics are used for colouring concrete, bitumen, asphalt, tiles, bricks, ceramics and glass. They are also used extensively in house and marine paints. Because the shapes of the particles can be accurately controlled and the particle size distribution is narrow, synthetic iron oxides have a greater tinting strength than the natural ones and so, are chosen where paint colour is important, i. e., for top coats. Red iron oxides are used in primers for automobiles and steel structures. 

This process is used principally in Europe. It was first developed in 1854 for the production of aniline. Nitrobenzene was reduced to aniline using metallic iron, hence the process was termed the aniline or nitrobenzene process. Iron oxides were formed as unusable, grey/black products. Around 1925, Laux found that addition of iron chloride modified the process so that iron oxides suitable for use as pigments could be produced. With this additive alone, magnetite with a high tinting strength results, i. e. 

When determining the tinting strength of inorganic pigments, the tristimulus value Y (lightness) is usually used [1.37]. 

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