Shape and distribution of aluminum pigments

Shape and distribution of aluminum pigments

Most of the aluminum pigments used in coatings have a flake structure. How to ensure that the flakes can be arranged neatly in the coating film will directly affect the appearance effects of the coating film such as flicker, brightness, and metallic texture. Because the floating aluminum pigment floats on the surface of the coating film, the arrangement is almost automatic, and the effect will be very excellent.

Here we only discuss the arrangement of non-floating aluminum pigments, which are directly related to the formulation and construction method of the coating. In the drying process of the coating film, the aluminum sheet should first be ensured to be fully stretched, and then the rapid volatilization of the solvent will cause the coating film to shrink quickly, as a result, the aluminum sheet is pressed into a fixed arrangement. The stronger this effect, the better the arrangement effect. Therefore, the more rapid strong solvents in the coating formulation, the better, and the lower the solid content during construction, the better the effect. If the solid content is too high during construction, the solvent will evaporate too slowly, which will cause the aluminum sheet to roll up and down with the solvent and flow at will, resulting in disorderly arrangement, resulting in uneven coating film black and white, and large areas of mottling.

In order to make the volatilization and shrinkage of the coating film conducive to the arrangement of aluminum sheets, other materials can usually be used for reinforcement. Such as: CAB, NC resin with excellent solvent release, some wax dispersions, surfactants, etc. can also play a role in fixing aluminum sheets.