Ceramic coating Car

The natural seal of lotus petals is a marvel of organic molecules so small that we can speak of the micro and nano scale. It is part of the cuticle. This refers to the uppermost layer of the leaf, which has only the task of separating it from the environment. Its special structure, in conjunction with the chemical properties of the molecules, ensures that contact between the leaf and the water droplet is as minimal as possible.

Tiny nubs – known as papillae – vary slightly in height and cover the leaf surface like a forest. They are so small that they cannot be seen with the naked eye. To be precise, the papillae are about 15 to 20 micrometers high. Even the tiniest drop of water is significantly larger than each of these nubs. And that is one of the reasons why water cannot hold on well here. This is because the water droplets always rest on the top of the nubs and are unable to get into the spaces between them. These are also only about 15 micrometers wide. Penetration into the interstices would be necessary, however, so that the leaf of the lotus flower could be wetted.

In addition to the papillae, the wax layer that covers the entire leaf surface also plays a role. This means that every single nub is also waxed. Although this wax is not identical to the wax used as a car paint coating, the two variants nevertheless share common features. In chemical terms, a wax is a substance that is water repellent. In technical jargon, this is called hydrophobicity. This property arises because there are virtually no adhesion forces between wax and water droplets. These forces are a kind of attractive force.

The papillae therefore ensure that the water rests on the tips, so that it always has to maintain a tiny distance from the leaf surface. At the same time, the wax layer prevents the water from sticking to the leaf at all. But in addition to these valuable properties of the cuticle of the lotus leaf, the water also has a special property that helps to influence the lotus effect.

Water is characterized by its surface tension. This ensures that the water takes on a spherical shape and maintains the largest possible volume with the smallest possible surface area. Due to gravity or centrifugal forces, the spherical shape can naturally distort, so that it is not always obvious to us. But we can sense it in raindrops and see it in the shenanigans of the ISS crew in space. We can also see it in the lotus effect on the leaf of the lotus flower. Because the surface tension causes the water to take this special shape, it is prevented from getting deeper between the nubs in the cuticle.

The water is thus forced by itself to remain on the tips of the nubs. But of course the water would not roll off the leaf all by itself. Despite its sophisticated properties, some external influence is still necessary for this to happen. If the leaf lies crooked, the water can follow gravity and roll down or collect in the center of the leaf. Incidentally, it can evaporate there more easily than on other surfaces. This is because the adhesive forces, which are not strong, require less energy input. The wind is also able to set the water droplets in motion and leave the leaf surface again.

This is the secret of the lotus effect. But it exists not only in the lotus flower, but also in several other plant species. Often, but not always, they are found near water. The lotus effect also exists in the world of insects. Many insect wings have a similar sealing of the surfaces, so that the wings can reliably dry again after the morning dew.

Industry has discovered the effect for itself and is making great efforts to imitate the natural properties of the lotus leaf and use them for a wide variety of things. The reason: wetted surfaces are undesirable for various everyday objects. In the case of car bodywork, for example, they would promote rust and leave unsightly water spots.

The phenomenon of self-cleaning is also particularly interesting. However, while the plant and insect worlds swear by organic molecules that cause the effect, industry prefers to rely on inorganic ones. These usually have a longer shelf life because they cannot be readily broken down by microorganisms, and are also more durable because they cope better with environmental influences such as those caused by UV radiation.

However, while such a lotus leaf or insect wing is only hydrophobic (water-repellent), the industry goes one better with superhydrophobicity. A superhydrophobic protective layer is intended to achieve particularly intensive water repellency on surfaces, because even the finest water stains can easily spoil the appearance. In other words, the lotus effect is supposed to be outdone by man. With the right materials, this is no problem at all. With some ceramic coating prototypes, for example, you can equip your car with such a property.

Video Superhydrophob

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But there are many other possible applications besides the automotive sector. Water can become a disruptive factor on a wide variety of materials. These include glass, for example, but solar cells also benefit greatly from a sealant with superhydrophobic or at least hydrophobic properties. The reason is that, like a lotus leaf, the solar cell is designed to allow as much sunlight as possible to enter unhindered. Water and dirt only interfere with this.

Oleophobicity is also interesting in this context. Oleophobicity differs from superhydrophobicity in that the surface defies not only water but also the most stubborn dirt such as oil. If a surface is oleophobic, machine or olive oil can therefore be removed as easily as water on a lotus leaf – perhaps even better. Incidentally, the industry can make a surface both superhydrophobic and oleophobic. This is also possible on materials to which these properties are not usually attributed. These are textiles with their fine fiber fabric.

With a high-quality ceramic-based nanocoating! When this is applied to the surface of the varnish, a firm chemical bond is formed between the varnish and the coating. Although visually the varnish looks like an exactly smooth surface, on the molecular level it is not. The interconnected elements form numerous peaks and valleys. But these are so tiny that they can only be studied with technical aids.

For the protection of the car, however, these minimal unevennesses can have consequences. Because these are precisely the places where all kinds of substances are deposited, dirt or water, for example. If you wipe off stubborn incrustations and are too rough, you quickly rub off the paint as well. But then the bodywork loses its protection. Because our atmosphere is full of water (humidity) and salts, the bodywork quickly begins to rust in these places. Rust, in turn, causes the metal to decompose. It is only a matter of time before untreated rust spots form holes.

Anyone who now equips their paint with a ceramic coating is known to have a much lower probability of such rust spots occurring. The trick is that the ceramic fills the finest gaps in the paint at the molecular level, creating a solid branching that cannot be unraveled under any circumstances. This already results in a much smoother surface, which can already deter some damage. But like varnish, this coating also forms a continuous film, which once again covers the entire surface and forms a uniform layer. The paint is thus covered everywhere. If done well, not a single molecule of the varnish will protrude from the ceramic coating.

If you opt instead for a polish or wax coating, you can’t expect it to penetrate so deeply between the lacquer layer. In fact, the molecules of polishes and waxes remain on the lacquer layer. In principle, no branching occurs in the process. Although such layers last for a while, they are lost over time, so they have to be replaced again. What’s more, you can completely remove these layers again if you want to.