Cream Formulation with Multiple Whitening Actives: Compatibility and Base

Subject: Re: Inquiry about formulation

Regarding your cream formulation request with Activated Resorcinol 1%, TXC 3%, Vitamin B3 10%, Ectoin 5%, Alpha Arbutin 2%, and Mild Preserved Eco 0.5%:

Ingredient Compatibility:

• Generally, these ingredients can be combined in a formulation.
• However, the high concentration of Vitamin B3 (10%) combined with other potent actives like Activated Resorcinol, TXC, and Alpha Arbutin might increase the potential for skin irritation, especially for sensitive skin.
• Alpha Arbutin is most stable at a pH between 5.0 and 7.0. It is crucial to check and adjust the final pH of your cream to be within this range (ideally around 5.0-6.0) to ensure the stability and effectiveness of Alpha Arbutin and minimize the conversion to hydroquinone.
• Always perform a patch test before applying the product to a larger area of skin.

Cream Base:

• To create a cream texture, you will need an emulsifying system and thickeners to form a stable emulsion (oil-in-water or water-in-oil).
• A common approach for an oil-in-water (O/W) cream base suitable for these actives involves:
  • Water Phase: Water, humectants (like Glycerin), and most of your water-soluble actives (Vitamin B3, Ectoin, Alpha Arbutin).
  • Oil Phase: Emollients (various oils or esters), fatty alcohols (like Cetearyl Alcohol) which act as thickeners and co-emulsifiers, and potentially oil-soluble actives (Activated Resorcinol, TXC depending on its form).
  • Emulsifier(s): Ingredients that help mix the oil and water phases (e.g., Glyceryl Stearate SE, or a blend like Cetearyl Alcohol and Ceteareth-20).
  • Thickeners/Stabilizers: (e.g., fatty alcohols like Cetearyl Alcohol, or gums like Xanthan Gum) to give the cream body and stability.
• Mild Preserved Eco should be added during the cooling phase.
• You would typically heat the water and oil phases separately, combine them while hot, emulsify using a high-shear mixer, cool down, add heat-sensitive ingredients (like some actives and the preservative), and adjust the pH.
• Selecting the specific emulsifier and thickener system depends on the desired feel and stability requirements. You can explore various emulsifying wax blends or combinations of individual emulsifiers and fatty alcohols available in the shop.

In summary, the ingredients are generally compatible but pay close attention to the final pH and potential for irritation due to high active concentrations. For the base, use a standard O/W emulsifying system with emollients, fatty alcohols, emulsifiers, and water, ensuring the pH is adjusted correctly.