What's is kojic acid?
"Kojic acid" can be produced through the fermentation of various substances by Aspergillus (a fungus). Pure kojic acid is mainly produced by the fermentation of glucose. Kojic acid is a small molecular component with a molecular weight of 142.22, which can be directly absorbed through the skin. The English name of kojic acid is: Kojic acid. Ingredient alias: 2-hydroxymethyl-5-hydroxy-γ-pyrone. Since its discovery, kojic acid was first used in food, medicine, agriculture and other fields. In the field of food, it can be used as a food additive to keep fresh, preserve antiseptic and resist oxidation. Later, some research institutions found that "kojic acid" has a good whitening effect and can lighten dark spots. After this application was discovered, "kojic acid" began to be used as a skin whitening agent, and it was widely used in whitening and blemish products.
Why kojic acid works?
"Melanin" is the core component that causes the skin to become dark and spots appear, and it inhibits the production of melanin, which can have the effect of whitening and lightening spots. In the process of melanin production, "tyrosinase" is an essential catalyst. "Kojic acid" can snatch copper ions with tyrosinase, inactivate tyrosinase, block the production of melanin, and achieve the purpose of whitening and lightening spots.
Is kojic acid safe?
Kojic acid is not an acute, chronic, or reproductively toxic substance, and although some animal data suggest tumor promotion and weak carcinogenesis, kojic acid is absorbed very slowly from human skin into the circulation, and it is likely that the threshold for these effects will not be reached. Kojic acid is safe in cosmetics at concentrations below 2%. In practical application, a large number of statistical data show that consumers who have used "kojic acid" for a long time have no abnormal liver function, including liver tumors and skin cancer.
Regarding the safety of "kojic acid", after decades of research, it can basically be concluded that it is safe to use in cosmetics within a limited range, so there is no need to worry.
The stable of kojic acid?
"Kojic acid" is abandoned by most manufacturers. Apart from the above negative news, there is another important reason, which is "stability". Like all whitening products, "kojic acid" is afraid of light and high temperature, and it is easy to decompose and oxidize in these environments.
How to make kojic acid products that remain stable during the shelf life without oxidative decomposition poses a great challenge to formulators. Kojic acid has relatively high pH requirements. In an environment with a pH value of 4, it can withstand the challenge of high temperature. If the pH value of the product exceeds 5, it is easy to oxidize and deteriorate.
Therefore, if you use products containing kojic acid during the day, you should do a good job of sun protection to protect the kojic acid from acting on the skin. If it is not used for a long time, store it in the refrigerator to help moisturize the activity of kojic acid and prolong the shelf life.
What's Kojic acid dipalmitate?
Kojic acid dipalmitate, which is a derivative of kojic acid, has become a new favorite in the whitening market because of its good stability, good whitening effect and no irritation to the skin; kojic acid dipalmitate is composed of kojic acid and palmitoyl chloride Synthesized by acylation and purified by filtration, washing, decolorization, crystallization, recrystallization, drying and other steps. Kojic acid dipalmitate has excellent stability in the formulation, and will not produce chemical reactions with other ingredients in cosmetics, which reduces the difficulty of formulation. When the oil phase is heated to 75°C-85°C, it can easily melt into the oil phase and emulsify immediately, which is convenient for preparation. In clinical trials of pigmented patients, the effective rates of kojic acid and kojic acid dipalmitate were 60%-95% and 80%, respectively. The good fat solubility of kojic acid dipalmitate makes it easier to be absorbed by the skin and is a good moisturizer.
Recommend formula for kojic acid cream:
Note: A-165 is polyethylene glycol (100) stearate and glyceryl stearate. Preparation Process:
Add component A into the oil phase pot and heat up to 80-85°C;
Add component B1 into the water phase pot, heat to 80-85°C, add component B2 into the water phase pot, and keep the temperature constant for 20 minutes;
Add component B into the homogenizing pot, add component A, stir and emulsify for 5 minutes, and homogenize for 3 minutes;
Lower the temperature to 60°C, add component C, stir evenly, homogenize for 1 minute, cool down to 40-42°C, add component D, stir evenly, and cool down to room temperature to obtain the whitening and freckle removing cream.
For more information about kojic acid, please do not hesitate to contact us at chriswang@sheerherb.com.
