Formula Review and Mixing Instructions for Whitening Gel Lotion

Here is a review of your proposed gel lotion formula and suggested mixing instructions.

Formula Review

Your formula includes a combination of potent whitening ingredients at relatively high concentrations for a body lotion. While the individual usage rates are generally within the recommended ranges (with Activated Resorcinol S and Sym White at the maximum recommended for leave-on products), combining multiple strong actives at these levels might increase the potential for skin irritation, especially on the body which can be more sensitive than the face. It is highly recommended to perform a patch test on a small area of skin before applying the product all over the body.

The ingredients you have chosen are:

• MSH White (Undecylenoyl phenylalanine) 5%
• Activated Resorcinol S (4-butyl Resorcinol) 5%
• LipidSoft Lite (Isononyl Isononanoate) 5%
• Trans White (Tranexamic Acid) 3%
• Lemon Skin (Lactobacillus/Citrus Medica Limonum (Lemon) Peel Ferment Extract) 3%
• Reservoir-Tech 3%
• Sym White (Phenylethyl Resorcinol) 1%
• Mild Preserve Eco (Ethylhexylglycerin, 1,3 Propanediol) 1%
• Satin Cream Maker (Sodium Acrylates Copolymer) 1%
• Water 73%

Total: 100%

Suggestions for Improvement

1. Stability: To enhance the stability of Activated Resorcinol S and Sym White, it is highly recommended to add Disodium EDTA at a concentration of 0.2% to your formula. This ingredient helps chelate metal ions that can cause degradation and discoloration of these actives.
2. pH Adjustment: For optimal stability and efficacy of Sym White and Activated Resorcinol S, the final pH of your formula should ideally be in the range of 4-5. You will need to check the pH after mixing and adjust it using a suitable acid (like Citric Acid solution) or base (like Triethanolamine solution) if necessary.

Recommended Mixing Instructions

Here is a suggested step-by-step method for mixing your gel lotion:

1. In a main beaker or container, combine the Water, Trans White, Activated Resorcinol S, and Satin Cream Maker. Stir gently but thoroughly until the Satin Cream Maker is fully dispersed and the mixture begins to thicken into a gel-like consistency. If you are adding Disodium EDTA, add it here and stir until dissolved.
2. In a separate small container, combine LipidSoft Lite and MSH White. Stir them together.
3. Slowly add the oil mixture from step 2 into the water mixture from step 1 while continuously stirring. Continue stirring until the mixture is uniform and has the desired gel-lotion texture. Avoid high-speed mixing, as this can negatively affect the Satin Cream Maker.
4. Once the temperature of the mixture is below 40°C, add Lemon Skin and Mild Preserve Eco. Stir well to incorporate.
5. For Sym White: Sym White dissolves best in oil and is recommended to be added at the final step. You can gently warm a small amount of your gel-lotion base (e.g., in a small beaker placed in warm water) to around 40-50°C. Add the Sym White powder to this warmed portion and stir until it is completely dissolved. Then, add this warmed mixture back into your main batch and stir thoroughly to ensure even distribution. Alternatively, you can try dissolving Sym White in a small amount of LipidSoft Lite first, or add the powder directly to the final formula and stir for a prolonged period until dissolved (this may take time without heat).
6. Add Reservoir-Tech to the mixture and stir until it is evenly dispersed throughout the gel-lotion.
7. Check the pH of your final product using a pH meter or pH strips. If the pH is outside the range of 4-5, carefully adjust it using a dilute acid or base solution, adding drop by drop and stirring well after each addition, until the target pH is reached.
8. Once the pH is adjusted and all ingredients are fully incorporated, your gel lotion is ready to be packaged. Store the finished product away from direct sunlight and heat. Storing in a cool place or refrigerator is recommended for optimal shelf life of some ingredients.

Remember to perform a patch test before full body application due to the high concentration of active ingredients.