Ah so you're not talking about antifreeze used in cars but
IPA , well the advert is misleading as IPA needs to be diluted at
10% IPA to 90% water to stop the water freezing , but only
Works down to -4 then you will need to increase ratio.
It's not cost effective . But if you insist on trying it ,you'll be
Better of buy from ,litho supplies or Dow chemicals
But don't bother, average van carries / uses 400ltres water
So min IPA will need to be 40-50litres which equates to
A van with a driver that's as high as a kite on fumes and
Skint .
Pmsl