1.   A permanent coating of titanium oxide applied to the glass as it is being made gives it the self-cleaning properties.

2.   It is processed into titanium oxide, a lucrative material that is one of the whitest industrial pigments ever discovered.

3.   The titanium oxide attracts the water and makes it run down the glass in a continuous sheet.

4.   Titanium oxide is a white pigment used in paints, paper and cosmetics.

5.   To get the layer so thin it must rest on an underlayer of titanium oxide, which is not used on conventional floppy disks.

6.   A coating of titanium oxide gives the glass the ability to self-clean, Pilkington said.