Acidic and basic are two extremes that describe chemicals, just like hot and cold are two extremes that describe temperature. Mixing acids and bases can cancel out their extreme effects, much like mixing hot and cold water can even out water temperature. A substance that is neither acidic nor basic is neutral.
The pH scale measure how acidic or basic a substance is. It ranges from 0 to 14. A pH of 7 is neutral. A pH less than 7 is acidic and a pH greater than 7 is basic.
Pure water is neutral, with a pH of 7.0. When chemicals are mixed with water, the mixture can become either acidic or basic. Vinegar and lemon juice are acidic substances, while laundry detergents and bar soaps are basic or alkaline.
The skin produces both sebum and sweat, which create a barrier on the surface of the skin certain forms of bacteria and microorganisms, and it may be a factor in the natural skin shedding and renewal process. The pH of the acid mantle varies between 4.5 and 6.2. Skin care products should be below the skin’s pH of 4.5 – 6.8 to have maximum effects on the skin.
Very strong acids, such as sulfuric acid, can produce chemical burns that basically destroy the epidermis. Likewise, highly alkaline substances, such as lye, can also produce inflammation and in some cases, chemical burns.
pH adjusters or buffering agents are frequently added to skin care products. These additives keep pH at the correct level to produce the desired effect, while keeping the product safe and non-irritating to the skin.
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Increasing Acidity Neutral Increasing Basicity
Alpha Peel 40% = pH 1.8
Cocoa Cola = pH 2.5
Skin = pH 4.5 – 6.0
Ivory Soap = pH 9.5 – 10.5
Maximum results are achieved when the pH is between 1.8 – 6.8.
Next time we will discuss active ingredients that are beneficial to the skin.