SALICYLIC ACID
Salicylic acid is an important organic synthetic raw material.
Physical Properties:
| Melting Point | 158-161 °C(lit.) |
| Boiling Point | 211 °C(lit.) |
| Density | 1.44 |
| Vapour density | 4.8 (vs air) |
| Vapour pressure | 1 mm Hg ( 114 °C) |
| Refractive index | 1,565 |
| Flash point | 157 °C |
| Storage temprature | 2-8°C |
| Solublity | Ethanol 1 M at 20 °C, clear, colorless |
| pKa | 2.98(at 25℃) |
| Form | Solid |
| Colour | White to off-white |
| PH | 3.21(1 mM solution);2.57(10 mM solution);2.02(100 mM solution) |
| Water solublity | 1.8 g/L (20 ºC) |
| Sensitive | Light sensitive |
| Stability | Stable. Substances to be avoided include oxidizing agents, strong bases, iodine, fluorine. Combustible. Sensitive to light. |
- Salicylic acid can also be added in the treatment of acne and dandruff. Nowadays many famous cosmetic ingredients: in 1993, Clinique CLINIQUE first launched 1% salicylic acid in soft water cream, immediately became one of Clinique's most successful products; In 1998, SK-II crystal induced skin cream added 1.5%BHA ingredients to the original, and salicylic acid has effect of treatment pores and cutin like the egg peeling analogy that caused the market boom; open access Olay popular products activating cream also contains 1.5% BHA components. However, due to the high concentration of salicylic acid, it has a certain degree of damage, cosmetics containing salicylic acid concentration has generally been limited between 0.2%~1.5%, containing salicylic acid cosmetics shall be added to the note of warning signs to determine the safety of long-term use and children under 3 years of age also shall not be used.
- Salicylic acid is an FDA approved skin care ingredient used for the topical treatment of acne, and it's the only beta hydroxy acid (BHA) used in skin care products. Perfect for oily skin, salicylic acid is best known for its ability to deep clean excess oil out of pores and reduce oil production moving forward. Because salicylic acid keeps pores clean and unclogged, it prevents future whiteheads and blackheads from developing. Salicylic acid also exfoliates dead skin, and its anti-inflammatory properties make it a prime ingredient for those with psoriasis. Salicylic acid naturally occurs in willow bark, sweet birch bark, and wintergreen leaves, but synthetic versions are also used in skin care products.
Dosage
widely used in medicine, pesticides, dyes, rubber, food and perfumes. In the pharmaceutical industry, the main drug productions of salicylic acid are sodium salicylate, wintergreen oil (methyl salicylate), aspirin (acetylsalicylic acid), salicylic acid amine, phenyl salicylate. In dye industry, it is used for production mordant pure yellow , direct yellow 3GN, direct yellow GR, direct brown 3GN, acid mordant brown G, acid mordant yellow GG, acid yellow dye complex. In pesticide production, salicylic acid is used for the synthesis of organic phosphorus pesticide Isocarbophos, intermediate isopropyl salicylate isofenphos methyl and Rodenticide warfarin, coumatetralyl intermediate 4-hydroxycoumarin. In rubber industry, it is used as anti scorching agent and production of ultraviolet absorbent and foaming agent. It is perfume material, used for the preparation of methyl salicylate, salicylic acid ethyl ester; food preservatives, its sodium Salt is mostly used, now a number of countries have been banned; methyl salicylate can be used as oral cleaning agents, such as toothpaste flavor.