90% is better for fast drying but for cleaning, 70% is often much better. People forget just how good a solvent water is, and there are plenty of things that dissolve in water but not alcohol (as you’ve noted, salt is one).
That 70% is most useful for actual cleaning, whereas 90% is likely better for removing any water through mixing and evaporation. Ultimately it depends on which liquid and much of it you got in your device.
90% is better for fast drying but for cleaning, 70% is often much better. People forget just how good a solvent water is, and there are plenty of things that dissolve in water but not alcohol (as you’ve noted, salt is one).
That 70% is most useful for actual cleaning, whereas 90% is likely better for removing any water through mixing and evaporation. Ultimately it depends on which liquid and much of it you got in your device.