Salicylic acid is a beta-hydroxy acid known for over 6,000 years for its therapeutic properties. It is found in willow bark, from which it derives its name, as well as in many fruits (grapes, plums, apricots…) and vegetables (broccoli, cucumber, spinach, sweet potato…). Its soothing, keratolytic and sebum-regulating properties make it a valuable ally in the treatment of acne and blemishes. Here's a focus on its history and extraction process.
How is salicylic acid produced?
Summary
Published on July 26, 2024, by Maylis, Chemical Engineer — 4 min of reading
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Process of obtaining salicylic acid.
The willow is a shrub belonging to the Salicaceae family. The use of its bark spans millennia: it was from its extracts that in 1828, Johannes BUCHNER prepared salicin, an active ingredient with powerful anti-inflammatory properties. The hydrolysis of this molecule releases D-glucose and salicylic alcohol, a compound that can then be oxidised to give birth to thesalicylic acid.
In 1860, salicylic acid was first synthetically produced by the Kolbe-Schmidt reaction. Even today, this synthesis route is used to produce this active ingredient found in several Typology skincare products. The process of obtaining it is as follows: sodium phenate reacts with carbon dioxide under pressure, thus producing sodium salicylate. This then precipitates with sulphuric acid to yield the final product, salicylic acid.
Main applications of salicylic acid.
In medicine, salicylic acid is traditionally used for its effect as an exfoliant in squamous pathologies: it effectively treats warts and psoriasis. The destruction of desmosomes connecting the keratinocytes and the inhibition of prostaglandin production constitute its two biological modes of action.
In dermocosmetics, salicylic acid is particularly recommended for the care of oily skin due to its comedolytic and antimicrobial properties. It also helps to stimulate cell renewal and to brighten dull and grey complexions. It is also found in anti-dandruff shampoos (for oily flakes) and in hair care products, to restore shine and radiance to the hair.
In which Typology treatments can one find salicylic acid?
Typology has developed two treatments with salicylic acid:
Unlike the serum, the toner can be applied all over the face as it has a lower concentration of salicylic acid. Apply it with a cotton pad to the face and neck after they have been cleaned, avoiding the eye area, preferably in the evening, before the daily serum or night cream.
The local imperfections serum :
Containing 2% salicylic acid and 1% zinc, this serum purifies the skin and provides a comprehensive anti-bacterial action. It is applied in the evening, locally and in small amounts. One drop per spot is sufficient; initial results can be observed after three days.
Sources
WHITE J.W. Salicylic Acid: Its History and Applications, Glasgow Medical Journal Glasgow Medical Journal (1882).
JESKEY H. & al. The Kolbe-Schmitt Reaction. Chemical Review (1957).
