Learning from Mother Nature
Biomimetic facade paints for all substrates
Some ideas are so good that it would be a shame not to mimic them. That’s why there is biomimetics, a specialist field devoted to transferring the ingenious principles we find in nature to products that people use. SÜDWEST currently has four such products in its portfolio and uses them to ensure long-lasting perfect facades on all substrates.
Biomimetic, practical, good
The best known is surely the Lotus-Effect®: drops of water simply run off the leaves of the lotus plant, taking the dirt particles with them. The idea is perfect for facades and has been in SÜDWEST’s portfolio for 20 years. SÜDWEST Lotusan® and SÜDWEST Lotusan® Therm are water-repellent facade paints inspired by the lotus plant. They stop algae and fungi from growing on them, keeping surfaces clean.
Durable and versatile
SÜDWEST Lotusan® and Lotusan® Therm boast outstanding resistance to weathering and chalking. They are UV-resistant, permeable to water vapour, and particularly suitable for rendered substrates. The sides of a building that are particularly exposed to weathering benefit from the protection provided by the two silicone facade paints. SÜDWEST Lotusan® and SÜDWEST Lotusan® Therm are easy to apply and don’t leave any seams. Particularly matt surfaces are produced. Professional users also value the wide colour shade variety on offer.
Dual effect for areas with high levels of condensate
In addition to the natural protection provided by the Lotus-Effect®, SÜDWEST Lotusan® Therm features innovative encapsulated film protection against algae and fungi. This is deposited in the paint and gradually released over time. The dual-acting power of Lotusan® Therm is recommended for surfaces that are exposed to a lot of condensate, such as those close to bodies of water or forests. Even on these facades, microorganisms do not stand a chance.
How the Lotus-Effect® works:
When two different surfaces come into contact with each other, adhesive forces arise. For example, these can cause drops of water to adhere even to a vertical surface. The strength of these adhesive forces depends on factors including the size of the contact surface. A drop of water that can spread (wet the surface) is more likely to adhere. The Lotus-Effect® minimises the contact surface. This is achieved in two ways: a surface texture comprising papillae on a micrometre scale and natural hydrophobic waxes. This combination results in contact surfaces of just 0.6 per cent. The drop of water therefore tends to retain its spherical shape and cannot wet the surface. The water runs off, taking any dirt particles with it.
Suitable for all substrates
Less well known than the Lotus-Effect, but just as effective, is a principle from the animal kingdom. Namibia’s Atlantic coast is a dry desert region that extends far into the country’s interior. Yet despite these conditions, the fog-basking beetle manages to survive close to the coast. It collects the moisture from fog patches and uses this as drinking water. We have transferred this principle to our SÜDWEST Drytec® facade paint. Any form of water – whether rain, fog, or dew – runs off in record time. Facades are dry again in next to no time and algae and fungi have nowhere to grow. SÜDWEST Drytec® is also suitable for areas where there is a lot of condensate. However, the key advantage of SÜDWEST Drytec® is that the product can be used on a whole host of substrates. These include metal, external render, concrete, plastic, and EWIS.
How it works in nature:
The desert habitat of the fog-basking beetle is dust dry. Close to the Atlantic, however, it manages to collect the moisture from passing fog patches. The beetle balances on the crest of a dune and extends its rear up into the wind. Due to the bumpy texture and hydrophilic surfaces of its shell, fine droplets of fog gradually accumulate there and then flow over the hydrophobic areas of its body and into its mouth.
Flexible and economical
Using a special binder formulation, we were able to transfer the bumps that make up the beetle’s surface texture to the facade paint. Dew condenses on the facade and runs off. Drytec® can be applied using a paint brush, roller, or airless spray. The material has a particularly high spreading rate. The facade paint is suitable for a huge range of substrates in classic construction types as well as for buildings with EWIS. It is therefore rarely necessary to change products, significantly increasing efficiency on projects involving different substrates. In terms of design, Drytec® boasts a wide colour shade variety.
