When trying to make homemade chemical solutions to treat skin problems, it is very important to understand the role and safety of chemical components. The following are some chemical components commonly used in skin care, but please use them with caution and consult a doctor or professional for advice if necessary. ### 1. **Salicylic Acid (Salicylic Acid)** -**Function**: Salicylic acid is a β-hydroxyl acid (BHA), which is commonly used to treat acne, acne and blackheads. It can penetrate pores, dissolve oil, and promote the loss of the stratum corneum. -** Application**: Usually used in acne treatment products, the concentration is 0.5% to 2%. ### 2. **Fruit acids (Alpha Hydrogen Acids, AHAs)** -**Effect**: Fruit acids (such as glycolic acid and lactic acid) can remove dead skin cells, promote skin renewal, and improve uneven skin tone and fine lines. -** Application**: Commonly used in exfoliating products, the concentration is usually 5% to 10%. ### 3. **Benzoylperoxide (Benzoylperoxide)** -**Effect**: Benzoyl peroxide is an antibacterial agent, commonly used in the treatment of acne. It can kill the bacteria that cause acne and reduce inflammation. -** Application**: Usually used in acne treatment products, the concentration is 2.5% to 10%. ### 4. **Niacinamide (Niacinamide)** -**Function**: Niacinamide is a form of vitamin B3, which has anti-inflammatory, moisturizing and pigmentation-reducing effects. -** Application**: Commonly used in moisturizing and repairing products, the concentration is 2% to 5%. ### 5. **Tea Tree Oil (Tea Tree Oil)** -** Effect**: Tea tree oil has natural antibacterial and anti-inflammatory effects and is commonly used to treat acne and other skin infections. -**Application**: Usually used after dilution, the concentration does not exceed 5%. ### 6. **Hyaluronic acid (Hyaluronic Acid)** -**Function**: Hyaluronic acid is a powerful moisturizer that absorbs and locks in moisture and keeps the skin hydrated. -** Application**: It is commonly used in moisturizing products with a concentration of 0.1% to 2%. ### 7. **Urea (Urea)** -**Effect**: Urea has the effect of moisturizing and softening keratin, and is commonly used to treat dry and rough skin. -** Application**: Usually used in moisturizing and exfoliating products, the concentration is 5% to 10%. ### 8. **Zinc Oxide (Zinc Oxide)** -**Effect**: Zinc oxide has anti-inflammatory and astringent effects and is commonly used in the treatment of eczema, dermatitis and acne. -** Application**: Usually used in ointments and sunscreen products, the concentration is 5% to 20%. ### 9. **Vitamin C (Ascorbic Acid)** -**Function**: Vitamin C is an antioxidant that can brighten skin tone, reduce pigmentation and promote collagen synthesis. -** Application**: It is commonly used in antioxidant and whitening products with a concentration of 5% to 20%. ### 10. **Aloe Vera (Aloe Vera)** -**Effect**: Aloe vera has soothing, moisturizing and repairing effects on the skin. It is commonly used to treat sunburn, inflammation and dryness. -** Application**: Usually used in gel or emulsion products, the concentration is 90% to 100%. ### Precautions -**Dilution**: Many active ingredients need to be diluted before they can be used safely. Avoid direct use of high-concentration ingredients. -**Test**: Before using any new ingredients, it is recommended to test on a small area of skin to ensure that it will not cause allergies or irritation. -**Consult a professional**: If you are not sure how to formulate or use these ingredients, it is recommended to consult a dermatologist or a chemical professional. Homemade chemical solutions need to be handled carefully to ensure the purity and concentration of the ingredients to avoid unnecessary damage to the skin.