On 23rd September, 2014, TOTO Europe GmbH, the European subsidiary of the TOTO Global Group, convened a meeting of key HYDROTECT® partners in Casalgrande (RE), Italy. Those attending included Casalgrande Padana S.p.A., Crossville Inc., Laminam S.p.A. and Grespania S.A. At this meeting, the partners agreed to work collaboratively increase use and awareness of HYDROTECT® more throughout the global ceramic tile market. As a practical matter, keeping a building’s surface clean poses considerable environmental and financial challenges, with the high consumption of water, energy, and the use harmful chemical detergents being the primary ones. However, TOTO, the Japanese plumbing manufacturer, has discovered self-cleaning surfaces result from super-hydrophilic (water attracting) material surfaces that are created by baking titanium dioxide (TiO2), a semi-conducting photocatalyst, into the surface of ceramic tiles. Using only natural resources such as sunshine, HYDROTECT® decomposes a multitude of compounds: air-borne pollutants (such as nitrous oxide [NOx]; significant factors in smog); “dirt” (including exhaust gas, grease and oil) and the bacteria that cause odors. Once catalyzed, air-borne pollutant breaks down into less harmful substance (NO3-) and dirt loses its adhesive power. These compounds are easily washed away only by rainwater or by simple rinsing. In indoor applications, HYDROTECT® decomposes bacteria and reduces malodor causing by bacteria even in a darkened room thanks to its hybrid structure with noble metals.
The Development of Active Cleansing Surfaces
In 1967, Japanese scientists Akira Fujishima and Kenichi Honda (University of Tokyo) discovered the active cleansing effect of titanium dioxide in photocatalysis. They researched this phenomenon, now known as the “Honda-Fujishima Effect”, and in 1972, published their findings in an article entitled, ““The Effect of Photocatalyst TiO2,” in Nature, the international scientific journal of original, ground-breaking research. However, the additional passive cleansing effect of photocatalysis was only discovered in the 1990s by development engineers at TOTO, who were collaborating with the University of Tokyo. The additional passive cleansing effect is based on the hydrophilic properties of titanium dioxide. Surfaces treated with titanium dioxide dramatically reduce the surface tension of falling water. Instead of rolling off the surface as individual drops, the water flows off the edges in an ultra-thin film, which removes all dust and dirt particles in the process. Unlike the so-called lotus effect (hydrophobia), water applied to the titanium dioxide-treated surface was able to eliminate even oily and greasy substances without leaving a dirt film behind. Thanks to this extraordinary discovery, TOTO successfully introduced world first photocatalytic tiles to Japanese market in 1994. Currently, a wide range of materials are to create exterior façades and outdoor surfaces as well as interior walls and flooring materials, including ceramic tile, aluminium, paint, glass, etc. All of these building materials can be coated with HYDROTECT®.
From the left: Mr. Frank Douglas, Vice president of Crossville Inc., Mr. Luis Hernández Sanchis, CEO of Grespania S.A., Mr. Franco Manfredini, CEO of Casaglrande Padana S.p.A., Mr. Kazuo Sako, Executive officer of TOTO ltd., and Mr. Alberto Selmi, CEO of Laminam S.p.A..