ECS 2023: Wacker presents new silicone additive for silicate-based interior coatings

Without impairing their ability to breathe, wall paints and coating plasters produced with the new Silres BS 338 silicone additive from Wacker are given a hydrophobic, water-repellent surface that is only slightly absorbent. Manufacturers thus have significantly more options for tailoring their silicate paints to market requirements. Silres BS 338 complements Wacker's additive portfolio for interior paints. Unlike conventional silicone additives, the new product can cope with the high alkalinity of coating materials that - like silicate paints and silicate plasters - contain a water glass as a binder. Silicate paints and plasters modified with Silres BS 338 are consequently characterized by high storage stability.

Silres BS 338 contains a reactive polysiloxane as active ingredient. On setting, the silicone forms a solid, indissoluble bond with the surface of the filler and pigment particles contained in the coating materials. This leads to permanent effects in the coating. With its silicone-typical low surface tension, the new additive improves the wetting properties of the coating material and lowers its viscosity. These two effects ensure that the coating material flows well during application. This makes it much easier to achieve even, uniform and streak-free paints and coatings than was previously possible with silicate paints and plasters. Silicones typically have a hydrophobic effect. This also applies to Silres BS 338. Coatings formulated with the additive are water-repellent. Hydrophobicity means that water droplets do not penetrate, but instead roll off the surface. In addition, the new silicone additive significantly reduces capillary water absorption and thus the absorbency of the coating. A silicate paint finished with Silres BS 338 can thus also be used in damp interiors. The European Coatings Show will be held in Nuremberg from March 28 to 30.