Question: what is the difference between alkaline and acid perms?
Answer: People with damaged hair should use acid perms instead of alkaline perms though. ... Alkaline perm has a pH balance of between 8.2 and 9.6 while Acid perm has a pH balance of between 4.5 and 6.5. 5. Alkaline perm is stronger and is good for coarse and thick hair while Acid perm is gentler and good for damaged hair.