Viscosity is the intermolecular force of liquids. For inks, the intermolecular forces mainly come from pigments and resins. The reduction of ink viscosity mainly depends on low viscosity solvents (diluents). 

The diluent separates the resin molecules from the pigment molecules and reduces the force between them, thus reducing the viscosity of the ink. 

Viscosity is an important indicator of inkjet ink because when the viscosity of the ink is too high, it will block the sprinkler and cause ink breakage because of the difficulty of ink flow. On the contrary, when the ink viscosity is too low, it is easy to drip or drip ink. 

The viscosity of ink is greatly affected by temperature. when the temperature decreases, the viscosity increases. It is very important to keep the temperature of the workshop at 15-25 ℃ as far as possible. If the temperature of the inkjet workshop is too low, it will cause the cold substrate not to absorb ink. There are "fisheye"-like white spots.