Salicylic Acid is a beta hydroxy acid found in many plants but it's most well know source is White Willowor Salix alba from which it's name is derived. Salicylic acid is the active metabolite of the drug Asprin (Acetylsalicylic acid) a well know pain reliving medication.
Topically, Salicylic acid is most commonly found in products used to combat acne and other skin conditions such as dandruff. It acts as a comdeolytic and bateriostatic agent meaning it stimulates the shedding off dead skin cells, unclogs pores, and inhibits the growth of potentially acne-causing bacteria. These properties also make it useful as a 'chemical peel'.
|Melting Point||159°C (318°F)|
|Usage rate||Typical use level 0.5-3%. Typically, it is added to the water phase of formulas but it is only slightly soluble in water. If used at concentrations higher than 2%, propylene glycol should be used as solvent. Salicylic acid can be added also in powder form to a finished cream or lotion without dissolving it first in water or another solvent.|
|Applications||Peels and exfoliant products. Anti-acne products (max. 2%). Anti-dandruff products (max 3%).|
Water: about 0.2% at 20oC, about 1.7% at 75oC (by adding about 5% of sodium phosphate or another neutral salt, solubility of salicylic acid in water is increased to about 1.8%)
Alcohol (ethanol): about 14% in pure ethanol, about 0.5% in 20% ethanol
Propylene glycol: about 3-6%
Glycerin: about 1.6%