Лако-красочные материалы — производство

The tinting strength is a measure of the ability of a colorant to confer color to a light­scattering material by virtue of its absorption properties. The lightening power can be considered as the tinting strength of a white pigment, and is a measure of its ability to increase the reflectance of an absorbing (black or colored) medium by virtue of its scattering power. Tinting strength is expressed as the mass ratio in which the reference pigment (mass, mR) can be replaced by the test pigment (mass, mT) to give the same color quality in a white system. Analogously, lightening power is the mass ratio in which the reference pigment can be replaced by the test pigment to give the same lightness in a colored system. Thus, the same equation defines tinting strength and lightening power:

P = (mR/m, T) AQ=const

where AQ = const expresses the tinting strength matching. Both parameters are yield properties; if, for example, tinting strength is doubled, only half the weight of pigment is required. Optical properties can therefore provide information about the economic performance of a colored pigment (“value for money”). Testing of tinting strength and lightening power can be rationalized by means of the Kubelka-Munk theory (see Section 1.3.1).

1.3.3.1