Additives for wetting pigments, paints and surfaces

In the field of paint chemistry as in that of application, adjuvant additives play a fundamental role in the use of pigments or liquid preparations on supports. Wetting additives are involved in several ways, at different stages and without them, our paints would not be so effective, nor easy to apply. The first role of wetting additive takes place during the grinding and dispersion of pigments into dry powder.

These very fine particles tend to clump together, and by their size, and by the surface tension effect, they are naturally more difficult to wet, to coat, by the different liquids (water, solvents ,..) that we add. They therefore make it possible in the first place to act at the microscopic level by ensuring good wetting of the pigment particle, whatever its material, shape and size, which is essential in order to be able to disperse the pigments and keep them in suspension.

Additive and wetting agent in the manufacture and application of paint

Previously, we talked about the coating and “soaking” of the pigment by liquids on a microscopic scale. In this second paragraph, we are going to talk about surface tension and how to deal with this problem, for the paint manufacturer, or of course for the applicator. What happens if water is sprayed or projected onto a surface, such as bodywork varnish: the water or the liquid will form drops. The liquid product will shrink, it just won't "wet" the surface. This is due to surface tension.

Wetting additives and wetting agents are active and concentrated products that exist in both water-based and solvent-based paints and are used in the composition of all paints and varnishes. A wetting additive will allow the paint film to spread completely, whatever its thickness and the surface, without creating dry areas or shrinkage.

How to make your own wetting agent ?

You surely have this very effective wetting agent at home, it's your dishwashing liquid : mix a few drops with water and wash the surface of your bodywork, you will obtain a temporary disappearance of the surface tension. Not to mention that dishwashing liquid is a good degreaser that will eliminate a good part of the contaminants present and even invisible on the surface.

Wetting by flaming or wetting agent

There is a process in which a shiny part is silvered with very liquid chemical solutions, in order to give it a mirror chrome finish. In this technique called "silvering", it is extremely important that the surface allows liquids to come into contact with it completely and perfectly. Two methods are used for this, they are : • an anti-surface tension pre-treatment made with the wetting agent (brown natural product). It is very effective and it is practiced on parts that do not support other treatments. • Flamming using a torch and a blue flame : by licking the surface, the flame removes the surface tension.

Defoaming additive
Dispersing additive