★ Controlled flocculation dispersant

Dispersants with special structure can form hydrogen bond with each other, and when one of them is adsorbed on the surface of the pigment, the other end will form hydrogen bond with another dispersant, which will pull in between the pigment particles, but will not form real flocculation, this situation is called "controlled flocculation" or "controlled flocculation", and this type of dispersant is called "controlled flocculation type dispersant".

The controlled flocculation dispersant can prevent the floating color of the system by reducing the movement ability of pigments and balancing the difference of the movement ability of different pigments. In addition, flocculation system increases the low shear viscosity (thixotropy) of the system, which also increases the motion resistance of pigment particles. At the same time, some controlled flocculation dispersants will add a small amount of organosilicon leveling agent at the same time, to prevent or reduce the Benard vortex, increase the effect of anti-flare-up. Because the controlled flocculation will form a three-dimensional spatial structure, resulting in thixotropy of the coating system, but also play the effect of anti-current hanging and anti-sinking.

Also due to the above reasons, controlled flocculation will also bring about the decrease of leveling, bubble stability (thickening and thixotropy caused) and other adverse effects. At the same time, this type of dispersant has limited compatibility with most resins, which also affects shine and fullness. Therefore, this kind of dispersant is usually used for the appearance of the system does not require high, such as primer and paint, anticorrosive coating or coil coating of the back paint. Can also be used for decorative finish paint, but the amount is usually within 0.1-0.5%.

★ Flocculating dispersant

The deflocculating dispersant can reduce the viscosity of the system and improve the fluidity of the coating system, so that the viscosity of the system is close to Newtonian fluid, almost unaffected by the shear force. At the same time, the pigment particles obtained from the flocculation system are small, so it will enhance luster, improve leveling, enhance coloring power, increase hiding power or transparency. Therefore, deflocculating dispersants are often used in high demand finishes.