Hair Structure Part 3


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Jeni Giles

Well-Known Member
May 27, 2004
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Chubbuck Idaho USA
I've written about the layers of our hair, cuticle, cortex, and medulla. We've talked about how our hair grows, Anagen, Catagen, Telogen. I alluded to the effect of products on our hair. Before we can talk about that I have to tell about this.....

pH scale or Potential Hydrogen scale- a tool used to determine the acidity or alkalinity of a water based solution. The scale goes from 0.1 EXTREME acid to 14 EXTREME alkalinity. It is a logrithmic scale, meaning that each number is 10 times stronger than the next. 7 is neutral, distilled water.

The acid mantle- Every human has a thin layer of oil and sweat which is secreted by glands found in our skin and hair follicles. This layer helps protect us from invading bacteria, dirt and water. It also has a pH or potential Hydrogen factor of 4.5 to 5.5. This number is important to remember because we affect it with the services we do. Our hair and skin like to maintain that balance, which is slightly acidic.

Hair fibers protrude from follicles which are found almost everywhere on the human body. We don't have any on our palms or soles, but the rest of our bodies are covered with some type of hair.

Terminal or scalp hair grows out of the follicle and is protected by our acid mantle. The acid mantle keeps the cuticle layer tight and compact. When our hair is covered by the acid mantle it is in it's strongest condition. Pretty easy, keep the hair covered with the acid mantle, no brainer!!

What happens when we shampoo our hair? Water has a pH of 7, that's approximately 100 times more alkaline that our acid mantle. Then we add shampoo, which contain surfactants (chemicals that have a water loving-hydrophyllic end and an oil loving or lipophyllic end) and it strips the oil, dirt and product out of our hair and off of our scalp.

Now what??? Our cuticle layer is no longer protected by the acid mantle- we've added water and scrubbed it off- the cortex starts to swell and stretches the cuticle layer out. Each time we shampoo our hair we put it in a delicate state.

Ok, now we know that just shampooing can damage the hair (damage can be minimized by using acid balanced products, HINT salon products are acid balanced) But what about coloring, relaxing or perming? Colors have a pH begining in the 7.9 range, relaxers 11 and perms 6.9-9.0. Professional stylists use this to our advantage, we force the cortex to swell and stretch the cuticle to get the chemicals inside the hair. To lock the change in, we lower the pH. We use an acid balanced product to shrink the cortex allowing the cuticle to tighten and restore the pH to the normal range for skin and hair.

Right, who cares about that garbage? Any one who shampoos their hair or uses any type of styling product on it. If the products used on the hair are not acid balanced, the cortex swells and the cuticle stretches allowing changes to take place. The most notable change is the change in color,especially if you have color treated hair. The ends fade quickly and tangle easily.

What about permed hair? If you use a product that is not acid balanced, every time you shampoo you will loosen or relax your perm. Nothing like washing a chunk of money down the drain...personally I can think of other things I'd rather spend my cash on.

Naturally curly or wavy hair is even more dependant upon maintaining the proper pH. It's texture doesn't allow a smooth even coating from the acid mantle. This type of hair is more fragile becasue the cuticle cannot lay flat and provide protection. If a harsh alkaline product is used on naturally curly or wavy hair for an extended amount of time, hair breakage is bound to occur. I don't know about any one else, but I'm not fond of breaking my hair off- tried that in beauty school- didn't like the look.

"Better for the Hair" "Repairs Damage" I've seen these advertizing slogans and we should beware, products that make these claims usually contain large amounts of preservatives and wax which coat our hair, makes it feel nice, but doesn't actually do anything to repair or make our hair better. It does make it harder to perform chemical services though- keep this in mind when selecting a shampoo or conditioner. As of yet hair that has been damaged cannot be rebuilt. It must be grown out and cut off before it is healthy hair again. I'm sure in time chemistry will allow our hair to be rebuilt, but not yet!

All things considered, find a product, hopefully through professional reccommendation by your stylist who knows what services you do to your hair, and stick with it. Professionals stand by their work, in our school, we garuntee our services when professional products are used. If we have made recommendations and they aren't being followed when having a chemical service, we will not redo that service with out charge, our clients have come to understand the value of caring for their hair, their children and grandchildren are my future, not only as clients, but as students. What I pass on today means there will be some one to take care of me tomorrow.

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