Frozen out

AN environmentally friendly antifreeze that also deters graffiti artists is
being patented by Leonard Haslim of California (WO 00/00568). Motorists use
conventional antifreeze, ethylene glycol, to de-ice their windscreens and
airlines need it to prevent the wings of planes icing up. But the run-off can
pollute local water courses. Haslim’s spray is a mixture of propylene glycol and
propanol, which lowers the freezing point of water, and xanthan, which makes the
fluid stick to surface it is de-icing. The same mixture also stops ice forming
on car windows and road signs, and foils graffiti artists because spray paint
won’t…