Achromatism of pigments

1. Definition and content

One of the important optical properties of white pigments is the ability of white pigments to lighten the color of colored pigments under certain test conditions .

2. Test method

(1) There are visual method, instrument measurement method and Reynolds index method.

(2) Standard GB/T13451.2--1992 Determination of relative tinting strength of coloring pigments and phase scattering power of white pigments by photometer method.

(3) Principle

Test pigments and standard pigments of the same quality are respectively dispersed in the same black pigment slurry of the same quality , and the reflection factor or reflection coefficient of each dispersion is measured photometrically at a wavelength of 550nm or with an r color filter. Calculated with the corresponding K/S value.

(4) Operation Grind the standard black pulp and white pigment into a slurry, measure the reflectance at 550nm or under the gamma filter, find out the K/S value, and then calculate.

(5) Instrument flat Grinder and photometer.