What Is The Important Role Of Acid And Alkaline Resistance Of Pigments in The Application Of Water-based Inks?

The resins used in water-based inks are mostly carboxylic acid type, which are neutralized with ammonia and become water-soluble resins. Therefore, water-based binders are slightly acidic. If the pigment used for water-based ink is acidic, it may cause acidification of the water-soluble resin, leading to resin condensation and damage to the suspension structure of the ink. But pigments with strong alkalinity are prone to saponification of the resin; Pigments with high water solubility can also damage the stability of the binder, so the selection of pigments for water-based inks should consider factors such as their acidity, alkalinity, and water solubility.