The SILCO® product portfolio offers leveling and wetting additives for printing inks, overprint varnishes and versatile coatings as well as high-performance dispersing additives for pigment preparations.
In order to achieve a homogeneous and defect-free coating, a large number of factors and influencing variables must be taken into account.
After the application of water-based coating systems, currents and concentration differences often occur in the paint during drying. This can lead to the undesirable formation of a scar structure, comparable to a so-called orange peel, on the surface. Changes in density, temperature and surface tension are the decisive parameters of this effect.
This effect can be specifically counteracted by adding suitable leveling and surface additives. In addition to optimizing the flow, various surface properties can be adjusted with specifically modified additives:
Substrate wetting agents provide excellent wetting of surfaces. A coating system achieves optimal results when the surface tension of the coating is lower than the interfacial tension of the substrate.
Since water has a much higher surface tension than any organic solvent, wetting problems are often observed when using water-based formulations.
These disturbances can be prevented by the addition of suitable substrate wetting agents, as they significantly reduce the surface tension of the aqueous system. This leads to aqueous formulations with a wetting behavior comparable to solvent-based systems.
Wetting and dispersing additives act in two ways. As surface-active substances, they accelerate the wetting of the pigment agglomerates in the binder and also improve the stability of the pigment dispersion.
This prevents uncontrolled flocculation of the solids in the coating, which can otherwise lead to quality losses due to separation, low colour strength or so-called rub-out effects.
Wetting and dispersing additives are essential in pigmented and filled systems and guarantee: