Synthetic Glycolic Acid Formation.

Glycolic acid is a natural organic acid belonging to the family of alpha-hydroxy acids (AHAs or fruit acids). It is a small molecule that easily penetrates the surface layer of the epidermis and stimulates the skin's cellular activity. Indeed, glycolic acid is known for its exfoliating action on the dead cells of the horny layer. It allows improving the homogeneity of the complexion, to refine the grain of skin and to tighten the pores. It also reduces acne scars and dark spots by inhibiting the production of melanin in the melanocytes.

The raw glycolic acid structure CH2(OH)COOH, is formed synthetically from two reagents: formaldehyde (HCHO) and carbon monoxide (CO). First, formaldehyde is dissolved in water in the presence of an organic acid (in our case, it is sulfuric acid H2SO4). The acid is introduced to catalyze the reaction, i.e., it allows the glycolic acid synthesis to be faster and to have a better yield. Then, the solution is heated and pressurized in a reactor containing carbon monoxide. The glycolic acid formula equation is as follows:

HCHO + CO + HOH --> CH2OHCOOH

The reaction medium is then neutralized to recover the reaction products, especially glycolic acid.

Note: The higher the concentration of sulfuric acid, and therefore of catalyst, the less the reaction medium needs to be heated and the lower the pressure in the reactor.

The exfoliating serum with 10% glycolic acid is concentrated in exfoliating and astringent active ingredients. It effectively fights against blackheads and dilated pores, for a smooth and unified complexion. It is applied in the evening, before your usual night cream.

The exfoliating tonic contains glycolic acid, lemongrass hydrolate and vegetable glycerin. This care allows tighten the pores and to reduce the black spots. It is suitable for all skin types, except for sensitive and atopic skin due to its high concentration of AHAs, which can cause irritation or a glycolic acid reaction. It is advisable to use this lotion in the evening only. Soak a cotton pad with this care, then apply it to your already cleaned face. You can then apply your serum and your night cream.

The exfoliating night cream contains glycolic acid, mandelic acid and vegetable shea butter. Made with 94% natural ingredients, it helps tighten pores and reduce blackheads. Day after day, the skin's radiance is restored.

The peeling mask combines the exfoliating action of 4 types of AHA and a PHA to act at different depths of the epidermis. Used once or twice a week, in the evening only, it eliminates dead cells to unclog pores and refine skin texture. This gel-mask also helps to reduce the appearance of blackheads.

Note: By exfoliating the skin, the stratum corneum becomes thinner. The skin is then more exposed, more vulnerable and more sensitive. Therefore, the application of glycolic acid formulas is best done at night. The skin will then have enough time to regenerate during sleep.

• UNITED STATES PATENT OFFICE 2,152,852 PROCESS FOR MANUFACTURE OF GLYCOLC. ACO

• HEARING V.J. & al. Applications of hydroxy acids : classification, mechanisms, and photoactivity. Clinical Cosmetic and Investigational Dermatology (2010).

• KAWASHIMA M. & al. Glycolic acid chemical peeling improves inflammatory acne eruptions through its inhibitory and bactericidal effects on Propionibacterium acnes. Journal of Dermatology (2012).