Wetting and dispersing agents for two-component solvent-borne coatings

dh-6854 is a polymeric dispersant containing multiple anchoring groups, which has wetting and dispersing ability for various organic pigments, strong viscosity reduction ability, can reduce the operating viscosity of the grinding system, improve the pigment content in the grinding material, and the effect of using with the pigment derivative-type viscosity reducing agent–, meanwhile, it has strong ability to prevent flocculation and coarse return, and can improve the storage stability of the grinding–pulp. storage stability.

Physical index
Composition: polymeric block copolymer containing pro-pigment groups
Appearance: light brown-yellow transparent liquid
Active ingredient: 50%
Density: about 0.98g/ml

Pigments such as carbon black, phthalocyanine blue and phthalocyanine green and other organic pigments have a tendency to increase foam in water-based coatings, which may be the cause of the fine pigment particles. Water-based paints containing iron oxide pigments are particularly difficult to defoam because many defoamers affect the dispersibility of the pigments, and the defoamers themselves are easily adsorbed by the pigment particles. Therefore, when selecting defoamers, storage stability tests must be carried out. The effect wax dispersion quotes of filler on foam is not clear, but sometimes the foam will increase when talc is changed to silica, but it can be solved by increasing the amount of defoamer.

Dispersants have a significant effect on the foam of some water-based coatings. Polyacrylate dispersants have more foam than other types of dispersants. Generally speaking, dispersants with low dispersibility also have less foam. For example, diisobutyl sulfosuccinate (Ta mol 731). Relative to the pigment, there is little foam at 0.1%~0.25%. Certain dispersants will emulsify the defoamer first, which will cause pigment coalescence and defoamer failure.

The choice of wetting agent not only affects the amount of foam produced, but is also related to the type of defoamer selected. Excessive wetting agent will stabilize the foam.