The acidic nature of the skin surface was first determined by Heuss in 1892  .
Since then numerous studies have confirmed this observation.
 Heuss E: Die Reaktion des Schweisses beim gesunden Menschen. Monatschr Prakt Dermatol 1892; 14: 341–343.
Since the beginning of the 1950s, the flat glass electrode was used more and more for skin pH measurements  .
 Schirren CG: Does the glass-electrode determine the same pH values on the skin surface as a quinhydrone electrode? J Invest Dermatol 1955; 24: 485–488.
In the 1970’, a French medical cosmetic company launched acid skincare products which help the epidermis regain and express its original regenerating properties.
In 2019, the Swiss company launched acid pH therapy line in Russia, clinic group which was developed and modified from French products in Korea.
In 2020, the Chinese premium spa group launched pH therapy line which was developed in Korea.