Why Bleach Bath Works
Black Elephants
In a previous post, we went through the steps on how to remove tangles from human hair using a bleach bath. Now we are going to see why this detangling method works on human hair weave and wigs.
The key to this mystery is the power of hydrogen, or pH. You've seen this symbol used in chemistry class or when treating a swimming pool. The pH scale goes from 0 to 14 with 7 considered neutral. Plain water has a pH level about 7. Anything less than 7 is considered acidic, and anything above 7 is considered basic or alkaline.
Licensed under Creative Commons
Human hair has a pH level of 4.5 to 5.5 which is slightly acidic according to our pH scale. As long as the hair remains at that pH level, it is considered stable. So what happens when we put bleach on the hair? Well, bleach has a pH of about 12.5 which is on the opposite side of the pH scale to hair. This makes bleach a basic solution. And hopefully we all remember from chemistry that mixing an acid and a base causes a chemical reaction. This reaction is the forcing of the hair cuticles to rise up and expose the soft cortex underneath.
During the 3 minutes in the bleach bowl, the bleach is opening up the cuticles so that they are no longer interlocking into one another like a jigsaw puzzle or a zipper. This is why we begin detangling with a comb once the hair begins soaking in the bleach bowl.
Removing the hair from the bleach within 3 minutes prevents the bleach from drastically changing the color of the hair. The shampoo and conditioner bowl helps bring the human hair back down to an acidic pH level of 5. This locks down the cuticles before the hair can re-interlock (or tangle back up).
So what is the ammonia for? After all, ammonia has a pH level of 11.5 which is still highly basic. Ever clean a bathroom or kitchen using bleach AND ammonia. Together? That is considered a no-no because bleach plus ammonia produces very toxic vapors including chlorine gas.
So can we kill this step and skip the whole toxic gas thing? You can but you risk leaving some bleach on the hair. If left alone, bleach will continue to react with the hair causing noticeable color change. Ammonia neutralizes the bleach. Ammonia can also reopen the cuticles which is why we dip the hair in the ammonia bowl rather than soak.
So be smart and bleach bath your hair knowing why each step is important.
Have a blessed weekend!
-Aly