TAGS: European Coatings Show
At the European Coatings Show 2023, the Munich-based WACKER Group showcases a new silicone additive for formulating silicate paints and brush-on plasters for interiors. This product, which is available as an aqueous emulsion under the name SILRES® BS 338, facilitates processing of the coating materials, increases their storage stability and enhances the properties of the applied coating.
Wall paints and brush-on plasters produced with the silicone additive have the same breathability as before, but yield a hydrophobic, water-repellent finish that is only slightly absorbent. This greatly extends the range of options for manufacturers to tailor their silicate paints to market requirements.
Suitable for Interior Coatings
SILRES® BS 338 complements WACKER’s portfolio of additives for interior coatings. Unlike conventional silicone additives, the new product can cope with the high alkalinity of coating materials that contain a water glass as binder, such as silicate paints and silicate plasters. Wall coatings modified with SILRES® BS 338 are notable for their high storage stability.
The active ingredient in SILRES® BS 338 is a reactive polysiloxane. During setting, this forms a solid, durable bond with the surfaces of the filler and pigment particles in the coating materials. The resulting effects in the coating are permanent.
Thanks to its low surface tension, which is a characteristic property of silicones, 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 level, uniform and streak-free results than was previously possible with silicate paints and plasters.
Silicones are typically hydrophobic and this is also true of SILRES® BS 338: coatings formulated with the additive are water-repellent. As a result, water droplets do not penetrate the surface, but roll off instead.
In addition, the new silicone additive significantly reduces capillary water absorption and thus the absorbency of the coating as well. A silicate paint containing SILRES® BS 338 can therefore also be used in damp interior rooms.
Exhibits Hydrophobicity & Reduced Absorbency During Application
The hydrophobicity and reduced absorbency are also noticeable during application. Since the first coat already confers a certain amount of water repellency on the substrate, the second coat is absorbed less and so remains wet for longer. This gives the user more time to make corrections. As a result, silicate paints and brush-on plasters are much easier to apply.
SILRES® BS 338 is extremely effective. All its effects are achieved at application rates of 1 to 3 percent, without causing undesirable side effects. Water vapor in masonry is still able to diffuse through the coating modified with SILRES® BS 338. The coating remains breathable.
Silicate paints and plasters are mineral coating materials. As they are aqueous, water glass-based systems, they are solvent-free and odorless. They are free of biocides and therefore ideal for painting interiors used by people who, for example, may suffer from allergies.
Silicate-based coatings produce good-looking, matt and water-vapor-permeable finishes that are exceptionally durable. However, conventional silicate paints are not as easy to apply as polymer emulsion paints, and this can discourage the inexperienced from using them.
The new silicone additive SILRES® BS 338 helps to alleviate this hesitancy. Silicate coatings formulated with the new product are easy to apply, and this makes them ideal for manufacturers looking to enter new markets.
Explore SILRES® Range from WACKER
Source: WACKER