The paint world of the future

Times are changing and working with traditional microscopes has long been forgotten in advanced laboratories. Nowadays, the word nanotechnology can be found at every turn in everyday life. What is it and what can it be used for?

First and foremost, nanotechnology allows for the creation of structures on an atomic or molecular level. It is a relatively new approach that refers to the understanding and improvement of the properties of matter on a ‘nano’ scale: one nanometre (one billionth of a metre). But how big are these objects? This can be illustrated by comparing a human hair, which is 1000 times thicker, to the nano structure next to it. Let's consider why researchers have focused so much on such small elements, which should not be important.

Nanotechnology is becoming increasingly widespread and has huge potential, which will soon result in a revolution in many areas of our lives. Manipulating at the molecular level clearly dictates the direction that future nano-products (including varnishes) will take in the years to come. Nanotechnology has contributed to the development of specialised coatings known as ‘smart coatings’. These include, among others:

• Self-healing paint for external paintwork, which has been used for several years to paint SpaceX space shuttles and rockets sent to the international space station. Currently, in the automotive industry, such paints can be found on premium cars.

• Camouflage coating materials for the arms industry, the use of which can be seen in many prototypes of new military equipment. Unfortunately, the durability of such a coating is currently the biggest problem.

• Coatings that indicate system leaks and other malfunctions will, in the long term, be used not only in construction systems but also in the automotive industry, making it much faster and easier to detect leaks.

• Coatings that react in a specific way to temperature fluctuations, such as thermal coatings, are already available and their use in the automotive industry, especially in tuning, is becoming standard.

• The term ‘smart coatings’ also refers to paints with antibacterial properties, which use nanosilver particles. These materials are sometimes described as ‘functional coatings’ because of their function - in this case, antibacterial. The nanoparticles of some fillers (including silica) increase the mechanical resistance of wood varnish coatings, and nano-sized metal oxides protect painted surfaces from UV rays and provide good anti-corrosion properties. In the production of varnishes, nanotechnology products are also used as a binder, which increases adhesion to the substrate and ensures excellent filling of the substrate pores.

Self-cleaning car paint

For example, silver nanoparticles have a much stronger bactericidal and fungicidal effect than silver in macro or micro form, and their effectiveness increases proportionally with the reduction of particle size (the smaller the particles, the larger the active surface). German and Japanese automotive corporations are positive about this technological solution. Research is being conducted on the use of similar coatings in public transport.

Self-cleaning and antibacterial surfaces can work wonders in the face of ever-growing cities (Tokyo already has 38 million inhabitants). Coatings are produced using organic and inorganic materials, as well as modern man-made materials such as composites and metamaterials.

Although new technologies for producing functional coatings have recently been developed on a large scale, they are often only suitable for laboratory use and cannot be applied to large surfaces. The challenge for technologists will therefore be to adapt these methods to the needs of industry so that functional layers can be applied to objects of any size.

Another problem with this type of coating is the unwanted interference between the individual layers applied to the painted surfaces. We can see that there is still a long way to go before we have products that meet all expectations.

Sometimes, on a daily basis, we see products whose properties we do not always appreciate. For example, we can make sure that our car's paintwork is at least a little ‘self-cleaning’. All we need to do is apply wax (e.g. Profix WAX) and in a short time, without interfering with the nano world, we not only get a mirror-like paintwork, but also, equally importantly, a surface that stays clean for a long time.