Solving Kojic Dipalmitate Crystallization in Oil Serum
Question
I tried making a Kojic Dipalmitate oil serum, but the Kojic Dipalmitate settles to the bottom once the oil cools down. I heat the oils to 80°C and then add the Kojic Dipalmitate and stir until fully clear. However, once it starts to cool, the oil turns cloudy and the Kojic Dipalmitate clearly returns to its powder form and settles to the bottom. I have to shake the bottle every time to use it. How do I achieve a clear oil?
My Formula:
IPM: 45%Sunflower oil: 47.5%Kojic dp: 2%Grape seed oil: 2%Jojoba oil: 2%Fragrance oil: 1%Vitamin e: 0.5%
Answer
The issue you are experiencing with Kojic Acid Dipalmitate crystallizing and settling is common in anhydrous (water-free) oil serums. While it dissolves at high temperatures (80°C), it can precipitate out as the mixture cools if the oil base cannot maintain the solubility at room temperature.
To achieve a stable, clear oil serum, consider the following adjustments:
1. Increase the Ester Content
Natural vegetable oils (like Sunflower, Grape Seed, and Jojoba) are often poor solvents for Kojic Acid Dipalmitate compared to esters. Isopropyl Myristate (IPM) is a much better solvent.
- Suggestion: Try increasing the Isopropyl Myristate to 60-70% of the formula and reducing the natural oils accordingly. This increases the "solvent power" of your base.
2. Check the Concentration
While 2% is a standard usage rate, it may be near the saturation point for your specific oil blend.
- Suggestion: Test a small batch at 1% concentration. If it remains clear, you can gradually increase the percentage to find the maximum stability point for your specific carrier oil ratio.
3. Cooling Rate
Sometimes, cooling the mixture too slowly allows large crystals to form and settle.
- Suggestion: After the Kojic Acid Dipalmitate is fully dissolved and clear at 80°C, try cooling the mixture more rapidly (e.g., placing the beaker in a room-temperature water bath while stirring) to see if it helps maintain clarity.
4. Ensure Complete Anhydrous Conditions
Even a tiny amount of moisture can trigger crystallization in oil-based whitening formulas. Ensure all your equipment and oils are completely dry.
Recommended Ingredients for your formula:
- Kojic Acid Dipalmitate: The active whitening agent.
- Isopropyl Myristate (IPM): Acts as the primary solvent and helps with skin penetration.
- Sunflower Oil (High Omega, Refined): A lightweight carrier oil.
- Grape Seed Oil: Provides antioxidants.
- Jojoba Oil: Mimics skin sebum and adds stability.
- Vitamin E (Tocopheryl Acetate): Protects the oils from rancidity (oxidation).
Related Products Mentioned
Vitamin E (Tocopheryl Acetate)
Jojoba Oil (Golden - Deodorized)
Kojic Acid Dipalmitate
Isopropyl Myristate (Deodorized)
