4) The Chemical Science Behind Hair Perming

Hello there everyone!

Today is the day that we get down to the hard facts about what really happens when you perm your hair. 

(http://us-marketsuccess.com/Blog/the-cold-hard-facts/)

So, how should we go about this? 

I'll begin by explaining the main goal of the chemical process, the steps and chemicals used... 

The main goal of hair perming is to penetrate the cortex of the hair shaft to alter the texture of the hair. The cortex of the hair is also home to the moisture and the natural pigment of the hair (melanin) and that is why previously chemically-treated hair is not as viable for perming, because the dyes of hair colour target the cortex and alters the melanin pigment and throughout these treatments, the hair's natural moisture content will also decrease throughout these chemical treatments.

And again, before we start talking about the steps, let's talk about some physical and chemical properties about the perm solution and neutralizer...

• Physical; liquid, ammonium thioglycolate has a strong ammonia scent (very alcoholic and very uncomfortable for the nose, irritating)(can be described as a repulsive skunk-like odour), clear colour, molecular mass: 109.15 g/mol
• Chemical; exists in a solution of an equilibrium mixture, not combustable (easily), weak acid, reacts to reform disulfide bonds in the hair, concentration up to 15.2% (thioglycolic acid), toxicity: medium-high; can cause respiratory problems, allergies and allergic reactions, skin conditions

Let's go through the steps to perm the hair, shall we?

Step 1 - Consider the factors that will influence the service; temperature of the salon, direction and size of the curl required, hair condition, previous chemical treatments and hair texture. All of these factors can contribute to either a fantastic perming treatments or one that has failed miserably. 

Step 2 - Wash the hair using shampoo, it doesn't have to be a specific kind of shampoo, but try to use a moisturizing formula because we are going to be stripping the hair of a lot of its natural moisture. We want to keep the hair as hydrated as possible.

(http://www.sheknows.com/beauty-and-style/articles/813278/salon-etiquette-101-how-to-tip-and-more)

Step 3 - Dry the hair as much as possible with a towel to remove excess moisture from the hair; the hair should be damp.

(http://www.videojug.com/film/how-to-towel-dry-hair)

Step 4 - Consider the type of curl your client wants; if they want a tighter curl, use a smaller rod. If they want a looser curl, use a bigger rod. Pick the rod size and start wrapping each section of the hair, allowing all hair to be wrapped up. When finished, check for any strands that were possibly unaccounted for. 

(http://www.hairfinder.com/techniques/permrods.htm)

Step 5 - Apply Vaseline around the top of the head (i.e. hair line of neck, sides of head, forehead) to protect the skin from the chemical treatments that will be as follows. Press cotton rolls along the line of Vaseline to protect the skin even further, seeing as through the chemicals can potentially be corrosive to the skin.

(http://www.salonsdirect.com/product/hair/permanent-wave-and-straightening/perm-accessories/foam-wrap-perm-protection-(x2))

Step 6 - Now the chemical treatment begins... Apply the perm solution to the hair, specifically to each curl. Apply enough of the solution to saturate each curl, but not to the point where it is dripping wet.

(http://www.beautyundercover.sg/mens-perm-air-salon/)

WOAH WOAH WOAH... Let's pause for a second....

What exactly is this perm solution that we are speaking of?

Well, the perm solution consists of the chemical I had spoken of previously known as Ammonium Thioglycolate... chemical formula: NH4 + HSCH2COO .  It has a pH of approx. 5.5 to 6.5. This formula is placed on the hair and it works by penetrating the cortex of the hair, which holds the shape of the hair and the moisture content. The excess ammonia present in the solution helps the hair to swell so that the reactants can work their way through the layers of the hair and then breach the cortex. This solution also "deprotonates the thioglycolate molecule, enabling it to break open disulfide bridges" (Archived Blogs, 2014). This basically means that the solution breaks the bonds and reforms them to the shape that the curler has prepared for them; they reform slowly as they sit in the rollers. Want to see the chemical reaction for the rebonding process? Well, here you go...

Keratin-S-S-keratin + 2HS-CH₂CO₂NH₄ --> -HO₂CH₂CS-SCH₂CO₂H + 2NH₃ + 2HS-keratin 

(Keratin-S-S-keratin are the protein bonds of the hair)

(http://en.wikipedia.org/wiki/Ammonium_thioglycolate)

Here is a real great webpage that explains everything you need to know about Ammonium Thioglycolate... http://www.chemicalland21.com/specialtychem/finechem/AMMONIUM%20THIOGLYCOLATE.htm

Step 7 - Allow the hair to process while the bonds reform themselves and the hair swells to allow the solution to move deeper into the hair shaft. 

                                            

                  

(https://www.linkedin.com/today/post/article/20140816165214-190976645-living)

Step 8- After the hair has processed based on the manufacturer's instructions and the hair type of the client, a solution of hydrogen peroxide is placed on the curls to strengthen the hair, after the Ammonium Thioglycolate solution. This can also be known as the oxidation lotion which reconstitutes the disulphide bonds.

(http://www.lissakahayon.com/2013/11/new-hair-new-look.html)

Hydrogen Peroxide Structure

(https://www.youtube.com/watch?v=LxY8AL3Sp4Q)

Here is the chemical formula for that reaction...

2Keratin-SH + H₂O₂ --> Keratin-S-S-keratin + 2H₂O

Step 9- After allowing the second solution of Hydrogen Peroxide to process, the curls can be throughly rinsed and dried throughly with a towel. A neutralizer must be applied to each curl and allowed to process based on the manufacturer's instructions. What the neutralizer does is again just reconstitute the new bonds and neutralize the hair's pH levels again, considering that we have just added acid-based products to the hair which have seeped into the hair shaft quite significantly. 

And again...

(https://www.linkedin.com/today/post/article/20140816165214-190976645-living)

Step 10- Carefully unwrap the hair from each curler, being careful to not overstretch the hair. Massage the remaining neutralizing solution into your hair and rinse the hair again using lukewarm water. Apply a leave-in conditioner to the hair if desired and allow the hair to dry. Voila; beautiful hair! ... at least from the outside... 

(http://different-hairstyles.blogspot.ca/2013/12/most-beautiful-perm-hairstyles-2014.html)

In summary, the perming process of the hair consists of breaking down the hair's protein bonds and the shape/texture of the hair. When this is broken down using the perm salts, also known as Ammonium Thioglycolate, the hair will reform to the rod size that was placed in the hair at the beginning of the treatment. After the hair is process for a while, a Hydrogen Peroxide solution is placed on the hair to reconstitute the new bonds and strengthen the hair. This solution is left to process and finally rinsed out after a certain period of time. After rinsing, a neutralizer is placed on each curl to reconstitute the new bonds once more, but mostly just returning the pH levels of the hair back to a somewhat normal state, or at least as normal as close as they can get back to neutral, after the whole chemical treatment. Finally, a conditioner is placed in the hair, then rinsed out and the hair is dried, left to reveal a very nice new style. 

(http://cenblog.org/just-another-electron-pusher/2011/09/making-waves-the-chemistry-of-hair-perms/)

Before I end this post, I want to share with you a really fantastic video of how a perm works; what is the science behind a perm... in summary of course?

https://www.youtube.com/watch?v=v14CPmnggcE

AND I have another video of what the process of a perm looks like; what happens when you go to the salon? 

https://www.youtube.com/watch?v=K5FmQhgeLq4

OH and by the way; here is a fantastic picture that shows the different kinds of perms available depending on the chemicals used or the pH of the chemicals..

(http://www.hairfinder.com/info/permanent-waves.htm)

So, what are the benefits of all these reactions? You get gorgeous curls or waves; you end up with the hair you have always dreamed of! And not only that, your hair becomes much more versatile because of the more flexible bonds!

As you can see, hair perming is not just a simple aesthetic treatment, there is a lot of scientific knowledge that comes along side the knowledge of giving a perm.

Until next time,

-Emma