Chemical additives for automotive coating

They are used both in the composition of solvent-based car paints and in water-based paints called “hydro”. These are the additives for the formulation of car paints. An additive is a concentrated chemical that helps to correct or add characteristics, qualities or properties to a paint recipe.

In the field of the formulation of bodywork coatings, these additives are used in very low proportions ranging from 0.1 to 2% at most. In general, a preparation contains, in addition to solvents and resins, a series of 4 to 10 complements, without which the final product would produce defects, would be difficult to use, or worse, would be unusable.

Let's see a non-exhaustive list of the main products used by chemists to create high-performance and satisfactory paints at all levels : texture and film qualities adhesion gloss drying

Car paint additives

Wetting agents are invisible agents that allow the product to spread on a support, eliminating "surface tension". Without these products, we would have products on our bodywork that drip, or that form "refusals", or openings on the surface. To adjust the thickness of a product, thickeners are used (to make it more viscous, to prevent the product from flowing) or, on the contrary, "flow" promoters, which will thin the product and give it a homogeneous self-leveling surface in a way.

Gloss or gloss suppressor (matting agent) additives are fillers to modulate the degree of gloss of dry car paint. Adhesion promoter additives, such as the famous "silanes", forge links with the various supports and therefore allow the car paint not to peel off once dry. There are many other additives, so some are versatile.

Dispersant additives

In a preparation, when the viscosity is maximum, or on the contrary when you are not allowed to reduce the fluidity of the product, then this is where the dispersant additives come into play, maintaining a distance between each pigment, pushing them away from each other, so that they don't all clump together and form a separation in the paint.

Defoaming additives

In chemistry, they are among the most common : defoaming additives prevent the formation of foam. It is a product without which our paints could look like washing-up liquid as soon as they are shaken a little and would therefore be hellish to use. This particularly concerns water-based formulas.

Additives and wetting agents

Have you ever seen a drop resting on the surface of a glass plate ? It does not spread ! Why ? Well, it's because of the electrical tension on the surfaces. Additives and wetting agents or active tensioning agents allow the products to wet the surface immediately. We find them once again in our good old dishwashing liquid!

Epoxy resin binder
Nitrocellulose resin binder
Polyurethane resin binder
Solvent-based acrylic resin binder
Car paint solvents