Silica as Surface Modifiers

Silica additives are very effective in lowering the gloss of all kinds of systems - both solvent - as well as waterborne. The matting effect relies on the porous and uneven shape of the silica particles.

When added in a sufficient quantity to a coating or ink, they will extend beyond the paint surface when the film shrinks during the drying process, thus altering the film from a smooth and even - glossy - surface to a mat one.

The silica matting ability suits particularly in both solventborne or aqueous systems. However silica efficiency is limited in high-solid or solvent-free coatings because of the lack of film shrinkage when paint is drying.