The hair based on their condition are divided into three basic types: dry, normal and oily. As of recently in addition you can often hear a description of hair being mixed or damaged. Scalp skin condition determines the hair state as the skin is a source of hair. If you wish to have healthy and shiny hair, you need to have a healthy head skin as your hair obtain from it all the nurtients and strength they need for further development, growth and life cycle renewal. Normal healthy skin without any anomalies or problems in most cases contributes to the development of normal healthy hair. The pH value describes the degree of acidity or alkalinity (pH is a chemical indicator of acidity or alkalinity). Hair pH value has a direct impact on their condition. Normal healthy hair have an acid pH. It provides a closed up outer hair layer (cuticle) that protects inside cortical layer and insures a general strength, elasticity and shine for hair. Accordingly, the higher or more alkaline the hair pH is, the more raised their cuticle and opened up their cortex will be, making overall hair condition worse. So what’s the pH? This is the potential amount of hydrogen in the water. Neutral H2O water molecule consists of two molecules: H+ and OH. Depending on how many molecules of H+ and OH are present in the composition, i.e. depending on their relationship in a substance (liquid, skin, hair, etc.) it is being determined their acidity or alkalinity. In general pH scale has values from 0 to 14. Clean water, considered to be a neutral solution has a value set to 7, right in the middle of the scale. So all values of the scale with a pH from 0 to 7 cosidered to be acidic and from 7 to 14 - alkaline. When the pH <7.0 there is more molecules of H+ than OH molecules and an environment considered to be acidic - causes hair to harden and shrink. When the pH = 7.0 that means that there is an equal amount of H+ and OH molecules and it is considered to be a neutral environment. And when pH>7.0 there is more molecules of OH than H+ molecules, so environment considered to be alkaline - causes hair to soften and swell.

Different chemical treatments can significantly change the pH value of the hair. Alkalis during procedures are used to soften and swell the hair, while acids vice versa - to harden and shrink. Basic knowledge in this area can also help to answer the question why it is not such a good idea to use soap for your next hair wash.

 

The pH scale - chemical indicators of acidity and alkalinity: A - hydrochloric acid (pH from 0 to 1); B - lemon juice (pH = 2.2); C - vinegar (pH = 2.5); D - neutralizing solutions (pH = 3.0); E - hydrogen peroxide (pH = 4.0); F - hair conditioners (pH from 3.0 and 5.8); G - skin (pH from 4.8 to 5.5); H - hair (pH from 4.5 to 5.5); I - acidic hair chemical treatments (pH from 4.2. to 6.0 ); K - neutralizing preparations for hair perming (pH from 6.0. to 7.8); L - urine (pH = 6.0); M - distilled water (pH = 7.0); N - blood (pH about 7.5); O - semi-permanant hair dyes ( pH from 7.0 to 9.0); P - cold weaving lotions (pH from 9.0 to 9.5); Q - soaps (pH from 8.5 to 10.2); R - regular hair dyes (pH from 9.2 to 10.4); S - hair whitening treatments (pH = 10.0); T - hair depilation solutions (pH about 11.3); U - ammonia (pH about 11.6); V - alkaline solutions for hair softening (pH from 11.0 to 13.0); W - the alkalis (pH about 14.0).