The paintings of the future

The technological advances achieved by the industry allow us to see great developments, considered as futuristic, about to be brought to the market today. The creation of "smart coatings" and the mechanisms developed for the reduction of VOCs are the most significant achievements.

by: Vanesa Restrepo

It is no longer strange to read news of new coatings with amazing properties such as self-repair, scratch and UV resistance and even self-washing. In fact, more and more research and development departments of large paint manufacturing companies, as well as university institutions are focusing on the development of this type of products.

The main reason lies in the environmental and legal issue, since the number of countries that adhere to international regulations for the reduction of polluting elements in paints, especially VOCs, is growing, while encouraging the formulation of coatings with high resistance, so that they have a higher performance that demands less retouching or maintenance over time.

The future, now

The advances obtained in the field until today are due to the implementation of hybrids of materials, as well as nanotechnology, in research projects that aim at the conservation of water, energy and the environment in general. This was explained by Hugo de Notta, president of the Argentine Society of Coating Technicians, Sater, on the opening day of the last version of Andina Paint, held in Medellín, Colombia.

During the presentation, in which he reproduced the most important extracts of his successful dissertation at the European Coating Show, De Notta explained that innovation in the area of coatings is divided into four basic approaches: the development of reduced cost systems, the reduction of the impact on the environment, the increase in durability and the creation of so-called smart coatings, such as those exemplified at the beginning of this writing.

Variable technologies

The characteristics of the paintings that are developed will depend, to a large extent, on the area in which they will be used. Thus, if it is the United States, for example, most of the advances will be directed to the sector of paints for wood and stucco, while in China work is being done on materials that protect green concrete.

The light and UV radiation conditions of the area in which the paint will be applied, as well as the quality standards that are handled on the site will directly influence the development although the overall purpose will always be to have products with certain characteristics that make them efficient and good performance on the site.

Economic factors also have their weight, especially in regions such as Latin America, where the resources available for R&D are limited compared to the bloc of countries with more developed economies. So, we have that GDP per capita will directly influence the purchasing and investment capacity of the public (measured by per capita consumption), which in turn will have an impact on the number of companies producing paint, the type of products they develop and the budget they allocate for their own research.

Seeing graph 1, we can see that in the Latin American region, Brazil is the best placed country in terms of per capita consumption, with about 8,500 kilograms, quite close to what other nations such as the United States, Japan and Germany register, where the figure is around 10,000 Kg.

That is, the Brazilian economy is the one that shows itself most solid to the world, which is why it becomes an attractive place for investors. Applied to the reality of the industry, we see that certainly several of the suppliers of raw materials have installed their operations centers in that country, despite the fact that it is the only one, among the main economies of the region, non-Spanish speaking.

De Notta also cited the case of architectural paintings, (graph 2) where Brazil, again, is the only country that reaches an average similar to developed countries in the relationship of price and percentage growth. Here the international treaties signed by the countries are considered as influential elements, as well as the existing facilities to facilitate foreign trade.

Environment, the protagonist

Regulations on emissions of Volatile Organic Compounds (VOCs) have found in the recent global concern about climate change and the adoption of more environmentally friendly practices, which reduce our carbon footprint, the appropriate breeding ground to have the attention of all industry players and, in the European case, of the rulers.

Thus, we have that in the European Union mandatory measures have been implemented such as the "eco label" that only allows the most sustainable products to reach the market. However, the greatest achievement achieved is that of the REACH regulations for polluting emissions, adopted and adapted by different countries.

Recently the United States also had a breakthrough in this regard with the launch in 2009 of the California Air Resources Board standard, aimed at controlling VOC emissions. However, Latin America remains completely devoid of measures in this regard, while the deadlines established by the Montreal, Kyoto and, recently, Copenhagen Protocols expire.

Environmentally friendly alternatives adopted by companies include minimizing the levels of co-solvents and glycols, using high solid, powder or radiation-cured paints; the use of new coalescence agents, plasticizers and alternative solvents, mixtures with soft latexes and use of latexes with own coalescence and stability to cold / heat cycles, pigmentation with low oil absorption, among others.

To this is added the discovery of acrylic acid from sugar cane, acrylic esters from renewable raw materials, polyols based on natural oils and alkyl alcohol (C8-C14) based on coconut seed oil.

All of the above is complemented by the intensive use of water-based paints, with fewer polluting compounds. In graph 3 you can see the evolution in the use of this type of paintings since its creation in the 60's.

Smart and well-performing paints

Respecting the definition given by Hugo de Notta, we have that intelligent paintings are the result of a careful control of architecture and composition at the nanometer scale. That is, they are made from principles and applications of nanotechnologies.

Among the most successful applications is the case of alumina and silica particles to increase scratch resistance in wooden floors, vehicles, safety glass and electronic displays. Silver ions have also been used for the development of new biocides, while selenium and cadmium nanoparticles have been used to create pigments with special effects and titanium dioxide has been applied to increase UV protection.

The most common uses include anti-reflective paints based on silsesquioxane, an organic/inorganic hybrid whose photoresistivity thickness has decreased, maintaining reflectivity control.

Scratch-resistant paint has also been successfully developed for vehicles, which also repel water and dust and give better finishes in terms of color and brightness. It is based on the use of CeramiClear, a nanosilica that polymerizes on the surface, and Progloss, an isocyanate varnish in which an acrylate is polymerized.

The capture of solar energy in buses, roofs and clothing has also grown with the development of paints receiving this type of energy, which create a series of nanocells from an inorganic nanorod embedded in a semiconductor polymer located between two electrons.

To these developments is added a long list of products that are still being tested and that could solve many problems of everyday life. So we have to work on the development of nanoparticles for the controlled release of drugs in the body, to absorb UV rays in cosmetic applications, for the identification of personnel and elements in combat and their camouflage before the enemy, paints with self-cleaning capacity, fast drying, effects to the touch (soft touch), among others.

The challenge for the industry is then to invest in new developments and get states to fix their eyes on the need to have a strict and current regulation for the control of polluting compounds. The alternatives today seem endless.