Pilkington Announces the World's First Self-Cleaning Glass

Pilkington plc, the world-leading glass manufacturer, today announces the development of Pilkington Activ™ - glass with a self-cleaning action that heralds a major innovation in the largest sector of the glass industry.

Incorporating the latest Pilkington online coating technology, Pilkington Activ™ self-cleaning glass has been developed for use in external windows. The product incorporates a proprietary dual action coating, using hydrophilic and photocatalytic properties to eliminate water and organic and inorganic deposits from the surface of the glass. The effects are continuous and will last the lifetime of the product.

The key element of Pilkington Activ™ self-cleaning glass is a microscopically thin, transparent coating of a specially developed compound. This patented coating is bonded permanently to the surface of the glass by a special manufacturing process. The overall thickness of the coating, which has several distinct chemical layers, is around 50nm (50 millionths of a millimetre - the equivalent of the thickness of a penny coin on top of the Empire State Building).

The surface coating has two important chemical properties which, when combined, make the glass "self cleaning". First, it is hydrophilic. It attracts water and causes it to "sheet" on the surface of the glass, preventing the formation of separate droplets and ensuring that loose particles of dust and dirt can be washed naturally from the surface during normal rainy weather.

Secondly, it is Photocatalytic. Ultra violet (UV) radiation - always abundant during daylight hours - causes it to react chemically with unwanted dirt and organic deposits, oxidising them and breaking their adherence to the surface of the glass. After an initial "running in" period of several days, during which the coating gradually becomes active, UV radiation absorbed during daylight hours is sufficient to ensure that the necessary chemical reactions continue through the night.

Pilkington Activ™ is being trialled in Ireland, Austria and North America from March, ahead of wider European and North American launches planned for the end of this year.

'Pilkington Activ™ self-cleaning glass is the latest example of the type of innovation that has secured Pilkington a reputation as a pioneer in the glass industry during the 20th century. This exciting new product, which virtually eliminates the chore of window cleaning, is expected to secure a significant part of the world's flat glass market. We look forward to launching the product at the end of this year (2001)'.