Self-cleaning paint uses light to cleanse walls


It sounds like something out of a householder's fantasy - walls covered with self-cleaning paint that repels dirt and grime.

But this new kind of paint is a reality now being tested on the walls of research lab at the University of Miami College of Engineering. The experimental initiative is designed to fit into the university’s commitment towards environmental sustainability on campus.

Dr. James Giancaspro - an assistant professor at the department of Civil, Architectural and Environmental Engineering - has applied the innovative product on the walls of his lab, where undergraduate and graduate students work.

The self-cleaning paint is an ecologically friendly product, Giancaspro says, which has the ability to keep walls clean and maintenance-free by repelling dirt, smog, bacteria, algae and fungus that normally accumulates on surfaces, eliminating toxic odours at the same time. He is currently in the process of designing ways of monitoring the anti-bacterial, anti-pollutant qualities of the paint.

The secret of how the paint works was discovered in the 1960s by Dr. Akira Fujishima in Japan. He found that titanium dioxide crystals, stimulated by ultra-violet light, could break down the molecules found in grime and organic matter that are necessary for bacteria to grow. This chemical process is called photocatalytic activity.

Using energy found in the UV light, the photocatalyst titanium dioxide can break down organic substances - such as oil grime and hydrocarbons from car exhaust and industrial smog, volatile organic compounds found in building materials and furniture, as well as organic growth such as fungus and mildew.

The contaminants are transformed into non-toxic molecules and reduced to such small quantities that they can no longer damage the surfaces.

A photocatalyst coating can control 'sick building' syndrome by removing volatile organic compounds emitted from building materials, carpeting and furniture - creating a purer space for more comfortable living and working.

Giancaspro says this 'eco-active' product was developed by Global Engineering - the Italian company that made the product available to the University of Miami scientist.

Although the paint is used in Europe and Asia, this is the first time it has been utilised in the United States. Global Engineering plans to fund research of the paint at the University of Miami, which may lead to development of the product for the US market.