Development of technology gives rise to innovations in industry. Technology is used in coating and paint industry to produce better quality and durable paints. Many companies producing coating and paint seek innovation in both their production technologies and raw materials used to produce better quality products in their R&D units. Nanotechnology is one
of the most frequently used technologies in the field of paints.
The word nano means ‘dwarf’ in Latin. Derived from this word, nanometer is a measure of length and means one billionth of a meter. Nowadays, study and development of materials in nanometer length and using materials in nanometer length together to produce new materials is known as nanotechnology. Artificially created particles in nano dimensions together with nano-size system components have significant new properties to develop new products and applications.
There are numerous areas where nanoscience or technology create positive developments such as material development, chemistry, physics or engineering sciences. Chemicals Industry played a very significant role in not just development of nano materials but also in their use in various applications. Another area where nanotechnology created a major improvement is coverings.
Nano coating and paints are produced using nanotechnology. Such new generation nano
coatings displayed major potential in diverse industrial applications by improving chemical resistance with their resistance against erosion together with abrasion and U.V. resistance properties.
Nanotechnology brought diverse opportunities to coating industry. Thanks to its small particle size, adding nano materials to coating ensured more functional coatings could be produced. Nanotechnology made it possible to produce diverse types of coatings and paint formulations.
Thanks to nanotechnology coating and paints that:
• Transmit heat and electricity much better,
• Prevent creation of mold, bacteria, and germs,
• Clean themselves,
• Clean the air, could be produced.
Especially the most recent developments in nanotechnology enabled production of coatings that are more resistant to scratches. It was noted that coatings produced with SiO2 nanoparticles were more resistant to scratches and abrasion.
Thanks to nanotechnology, self-cleaning coatings could be produced. Such coatings could be easily cleaned using rainwater. In 1997, Barthelott and colleagues examined lotus leaf. As a result of this study, it was determined that lotus leaves that could self-clean had hydrophobic and special surface morphology.
Based on findings of this study, lotus leaf pushes water thanks to its hydrophobic property
and as these water droplets roll, they carry dirt with themselves. With this hydrophobic property, surface of lotus leaf always remains clean.
Similar coatings were produced with this technology developed based on such properties of lotus leaf. Photocatalytic titanium dioxide (TiO2) was used in production of these coatings. The useful effect of TiO2 is its hydrophilic effect.
TiO2 brings forward the property known as ‘water chest’ in coatings. This effect ensures coatings can self-clean. Nano coatings with this property have photocatalytic characteristic.
Such coatings need natural or artificial UV source, oxygen (O2) and moisture to fulfil their functions. Thus, such coatings are more suitable to use on façades.
When meaning of the word photocatalytic is checked, it could be determined that it is very recent in the world and could be described as nano-technological and photochemical surface coating product that is friendly to organic materials and human health, that could be used for a long term after being used once, creating a chemical reaction using light energy.
Paints Produced Using Nano-Technology
In the simplest terms paints are produced using nanotechnology following the steps below;
• Partial hydrolysis of silanes,
• Modifying surfaces of nano-size metal oxide particles with the resulting hydrolysate,
• Dispersion in resin of nano-size metal oxides with modified surfaces,
• Addition of the created product to paint formulations in certain percentages.
Nano paints produced using nanotechnology are more resistant in many aspects. Paints with photocatalytic properties are produced using nanotechnology. Especially, these paints are more resistant in chemical terms.
The purposes of use of photocatalytic paints are to prevent bacteria (antimicrobial property), to clean water, to clean air, to self-clean and to remove odor. In particular, paints with this property are increasingly used in sterile environments such as operating rooms.
When we look at the coming years, we can predict that photocatalytic paints and coatings will be more frequently on the façades of buildings. Nanotechnology become an increasingly used technology to produce more durable materials.
Global studies on nanoscale still continue. The most important benefits of nanotechnology are extending the life of materials, keeping indoor comfort conditions in balance with passive methods, reducing energy and resource consumption in buildings, contributing to the elimination of structure-based negativities on the environment and human health. These properties, that materials gain with nanotechnology, are important in terms of sustainability.
Sustainability is becoming more and more important due to the climate crisis and disappearing resources. Thus, industries prefer sustainable production and products are preferred in industries. It is predicted that the demand for more sustainable paints and coatings produced with nanotechnology will increase.
• http://ijcea.org/papers/108-A530.pdf Nanotechnology-A New Prospective in Organic Coating -Review -A.Mathiazhagan and Rani Joseph
• http://www.ajesjournal.com/PDFs/08-2/2.%20Nanotechnology-A%20boon.pdf -Nanotechnology in HighPerformance Paint Coatings
Prepared by: Nilsu Kotil