Why is 70% alcohol solution a much better disinfectant than a 90% alcohol concentration? Wouldn’t a higher concentration mean better?

Question

Why is 70% alcohol solution a much better disinfectant than a 90% alcohol concentration? Wouldn’t a higher concentration mean better?

In: 5202

Answer 1

90% evaporate too fast, germ(infacting agent) can still survive after all the solution evaporated. 70% evaporate at slower rate so germ will die before the solution completed its evaporation.