1. Definition
Determination of the pH value of the suspension of pigments in water is a common method for determining the pH of the amount.
2. Measurement method
(1) Determination of the pH value of the standard GB/T 1717-1986 pigment aqueous suspension.
(2) The principle uses the potentiometric analysis method, an indicating electrode whose potential changes with the activity of hydrogen ions in the solution and a reference electrode whose electrode potential is constant under certain a working battery, and the pH is determined by measuring its electromotive force value.
(3) Operation Prepare 10% pigment suspension with distilled water, vibrate vigorously for 1 min, rest for 5 min, and measure its pH value with an instrument. The pH meter is shown in Figure 2-11.
