Glycolic acid is a water-soluble alpha hydroxy acid (AHA) made from sugar cane. It is one of the most widely used AHAs in skincare products.

Efficacy

Glycolic acid has the smallest-sized molecules of all the AHAs.This allows glycolic acid to absorb into the skin and exfoliate it even better than other AHAs.

Glycolic acid works by speeding up cell turnover.In other words, it dissolves the bonds that hold skin cells together. In effect, your skin is able to shed dead skin cells more quickly than it would on its own.

Glycolic acid triggers your skin to make more collagen as well.Collagen is the protein that makes skin firm, plump, and elastic. It also gives your bones and connective tissues their strength.

Your skin makes less collagen as you age. Collagen is also destroyed when you spend too much time in the sun. Using glycolic acid each day can help prevent the breakdown of collagen.

Preparation

Glycolic acid can be synthesized in various ways. The predominant approaches use a catalyzed reaction of formaldehyde with synthesis gas (carbonylation of formaldehyde), for its low cost.

It is also prepared by the reaction of chloroacetic acid with sodium hydroxide followed by re-acidification.

Other methods, not noticeably in use, include hydrogenation of oxalic acid, and hydrolysis of the cyanohydrin derived from formaldehyde.Some of today's glycolic acids are formic acid-free. Glycolic acid can be isolated from natural sources, such as sugarcane, sugar beets, pineapple, cantaloupe and unripe grapes.

Glycolic acid can also be prepared using an enzymatic biochemical process that may require less energy.

Applications

Glycolic acid is used in the textile industry as a dyeing and tanning agent,in food processing as a flavoring agent and as a preservative, and in the pharmaceutical industry as a skin care agent. It is also used in adhesives and plastics.Glycolic acid is often included in emulsion polymers, solvents and additives for ink and paint in order to improve flow properties and impart gloss. It is used in surface treatment products that increase the coefficient of friction on tile flooring. It is the active ingredient in modern formulations of Pine-Sol brand household cleaning liquid.