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Acids have many valuable properties, therefore they are widely used in the production of cosmetics and cosmetology. Salicylic acid is one of the most used acids. Where can it be found, what are its characteristics and what is its role in cosmetics? These are the key data: Published: 04-24-2023 What is salicylic acid? Salicylic acid is also called acidum salicylicum or o -hydroxybenzoic acid. Its name comes from the Latin word salix, meaning willow, from whose bark it was first extracted. This organic compound is classified as an aromatic hydroxy acid and consequently has a carboxyl group (COOH) and a hydroxyl group (OH) . The chemical formula of salicylic acid is as follows: C 7 H 6 O 3 . The discovery of salicylic acid is attributed to an Italian chemist, Raffaele Piria, who lived between 1814 and 1865. He was the first person to investigate the properties of salicin. In the 1850s, German chemist Hermann Kolbe isolated salicylic acidum . Where can you find salicylic acid? In nature, salicylic acid is present in plants. This compound keeps them healthy and protects them from pathogens and pests. It also stimulates their growth and improves the vital process of photosynthesis. What things contain salicylic acid? Salicylates, that is , the salts and esters of salicylic acid, are also found in many products that we use daily. These include, but are not limited to: certain vegetables and nuts, pickled fruits and vegetables, mustards, wines and other fermented beverages, certain fruit juices and concentrates, herbs and spices.
Under laboratory conditions, salicylic acid can be obtained by the so-called Kolbe-Schmitt reaction using sodium phenoxide and carbon dioxide. Salicylic acid: physical and chemical properties What are the characteristics of salicylic acid? It is a white or transparent, crystalline and odorless powder. It dissolves easily in hot water, ethanol , chloroform and ether. On the other hand, it does not dissolve at all or dissolves CZ Leads very poorly in cold water. The density of salicylic acid is 1.443 g/cm³ and its melting point is 159 °C . Salicylic acid: acceptable concentration Strongly concentrated salicylic acid irritates mucous membranes and can even cause skin burns. In cosmetics and medicines, appropriate concentrations depend on their function in a given product. Detailed guidance on the maximum concentration of salicylic acid is provided in Regulation (EC) No 1223/2009 of 30 November 2009. According to this regulation, the maximum concentration of salicylic acid used as a preservative in the manufacture of cosmetics is 0.5%. Furthermore, acidum salicylicum should not be used, among others, in cosmetics for children under 3 years of age (except shampoos). In certain rinse-off cosmetics, the concentration of salicylic acid used as a preservative should not exceed 2-3% (depending on the type of product and intended use). In prepared and compounded medicines, the concentration of salicylic acid solutions ranges from 1% to 10%.
There are also very strong cosmetic preparations available on the market that contain between 30% and 40% salicylic acid; These are specialized products that are used most frequently. in beauty salons. How does salicylic acid work? Why have people been using salicylic acid for over 150 years? The reason is that this compound has a very wide range of effects: it is one of the most effective disinfectants, bactericides, fungicides and regenerating agents. Facial treatments with salicylic acid reduce the amount of sebum and improve the general condition of the skin. Salicylic acid deeply exfoliates the skin, facilitating the removal of diseased or dead cells. (However, it is important to note that too much salicylic acid can cause dry skin.) Salicylic acid can also be used for skin discoloration. Its solution, applied in the appropriate amount, evens out skin tone and progressively eliminates hyperpigmentation spots. Additionally, salicylic acid can be used on the skin of the feet, making it easier to remove uncomfortable calluses and callused, unsightly skin. Salicylic acid in cosmetics What products currently contain salicylic acid? The use of this compound in cosmetics is very common. Salicylic acid is present, among others, in: acne toners, antibacterial gels and creams, exfoliants, soaps, masks, anti-dandruff shampoos. In the cosmetic and pharmaceutical industries , manufacturers again and again find new applications for salicylic acid. It is also used in products such as callus plasters, zinc anti-acne pastes with salicylic acid or exfoliating facial serums. Advanced preparations with high concentration of salicylates are also available on the market. These products are mainly used for professional local treatments for the face and body.
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發表於 2024-3-16 15:13:51