Cream Formulation Issues: Texture, Solubility, and Odor

Hello, I understand you are trying to refine your cream formulation to achieve the desired texture and efficacy. Based on the information you provided and the staff's responses, I will summarize and provide additional advice based on your questions.

Summary from previous recommendations:

• The staff recommended removing Deoxyarbutin and DMAE if you are concerned about irritation.
• It was recommended to increase the proportion of Satin Cream Maker to 1.5% or 2-2.5% if the texture is too liquid.
• It was recommended that Satin Cream Maker should be in the water phase, and mixing should involve gradually adding the oil phase to the water phase at a similar warm temperature.
• It was noted that Kojic Acid Dipalmitate will disperse in the cream texture, not dissolve completely clear.

From your latest experimental formula and process:
You have adjusted the formula by removing DMAE and changing Shea Butter to Apricot Kernel Oil, as well as adding Pro Polymer and Satin Cream Maker to the Water phase and moving Deoxyarbutin, Reservoir-Tech, SKIN-DEFENSE® V, Kojic Acid Dipalmitate, Sym-White™ to the Lipid phase, which is the correct approach for separating ingredients by type.

The problems encountered were a lumpy texture and a rather thick and sticky consistency, with a rancid smell (which you attributed to Shea Butter, but in the latest formula, you changed to Apricot Kernel Oil, which natural oils can also become rancid). You also had issues with AnyGel clumping in the first attempt and Pro Polymer clumping in the second attempt, as well as Chamomile Extract not dissolving well and Kojic Acid Dipalmitate being difficult to dissolve and making the Lipid phase thick upon cooling.

Answers to your questions:

1. Which oil can be used that dissolves easily and doesn't have a rancid smell?

   • The Octyldodecanol you have can be used instead of natural oils in the formula. It will help make the texture less sticky than Shea Butter or Apricot Kernel Oil and does not have a rancid smell. However, as the staff mentioned, Octyldodecanol is primarily used for color dispersion in makeup formulations, but it can also be used as an Emollient in general skin creams. If you want an oil with a light texture, easy absorption, and no rancid smell, you can consider using other light and easily absorbed Ester Oils or Silicone Oils such as Caprylic/Capric Triglyceride (MCT Oil), Isopropyl Myristate (IPM), Isopropyl Palmitate (IPP), or Silicone Oils like Cyclomethicone (which will be addressed in question 5) instead of natural oils.

2. Will using heat help Pro Polymer dissolve better? Will using less result in less thick cream?

   • Based on the staff's previous recommendation, it is advised to remove Pro Polymer from the formula entirely. Your formula already contains Satin Cream Maker, which functions to create the cream texture and emulsify oil into water. Using a high amount of Pro Polymer can lead to the uneven, lumpy texture you observed.
   • If you still wish to use Pro Polymer (which is not recommended for this formula), using heat (as you experimented with at 50-60 degrees) will help it dissolve and disperse more smoothly. And yes, using a smaller amount of Pro Polymer will result in a less thick cream proportionally.

3. Can the amount of Kojic Acid Dipalmitate be reduced?

   • Absolutely. Reducing the amount of Kojic Acid Dipalmitate will help make the Lipid phase more liquid and easier to mix when it cools down. Your formula already contains other whitening ingredients such as Ethyl Ascorbic acid, L-Glutathione, Tranexamic Acid, Deoxyarbutin, Sym-White™, which are sufficient for whitening purposes. Reducing Kojic Acid Dipalmitate to 1% or an amount that dissolves more easily based on your experiments is a good approach.

4. How to adjust the formula for a lighter, easier-to-spread, faster-absorbing cream?

   • Reduce the total amount of the Lipid phase: The proportion of the Lipid phase in your latest formula is 14.10%, which is quite high for a cream intended to be light. Try reducing the total amount of the oil phase, for example, to around 8-10%, by potentially reducing the amount of Apricot Kernel Oil or Kojic Acid Dipalmitate (as per question 3).
   • Use lighter oils/Emollients: Instead of using Shea Butter or Apricot Kernel Oil, which have a relatively heavy texture, try using Ester Oils or Silicone Oils that have a lighter texture and are more easily absorbed, such as Caprylic/Capric Triglyceride, Isopropyl Myristate, Isopropyl Palmitate, or Cyclomethicone (as per question 5).
   • Adjust Emulsifier: Ensure you are using an appropriate amount of Satin Cream Maker (1.5-2.0% as recommended by the staff) to achieve the desired consistency and stability.
   • Remove Pro Polymer: As recommended in question 2, removing Pro Polymer will help make the cream texture smoother and prevent gel lumps.

5. Can Cyclomethicone be added? Where to add it? Is an additional emulsifier needed?

   • Yes, adding Cyclomethicone (5-8% as recommended by the staff) will help improve spreadability and absorption speed, making the texture feel lighter and less sticky.
   • Add to the Lipid phase: Cyclomethicone is a Silicone Oil and should be added to the oil phase (Lipid phase).
   • No additional emulsifier needed: The Satin Cream Maker you are using is an Emulsifier capable of emulsifying oils into water, including Silicone Oils. Therefore, you do not strictly need to add another Emulsifier specifically for Cyclomethicone, although the total amount of emulsifier might need slight adjustment depending on the final percentage of the oil phase.

6. Regarding fragrance, which scent can be added? Can it be added directly?

   • You can add the essential oil or fragrance you desire to the formula. If you want a light, subtle scent like chamomile, you can use Chamomile Oil (Roman).
   • Add in the final step: As recommended by the staff, you can add essential oils or fragrances in the final step of making the cream, after the water and oil phases have been combined and the cream has started to cool down. Then, mix or stir to incorporate. Satin Cream Maker will help emulsify the fragrance into the cream texture.

Summary of recommended formula and process adjustments:

• Remove Pro Polymer from the Water phase.
• Reduce the amount of Kojic Acid Dipalmitate in the Lipid phase (e.g., to 1-2%).
• Consider changing the oil in the Lipid phase from Apricot Kernel Oil to a lighter, non-rancid Ester Oil or Silicone Oil, or use it in combination with the Octyldodecanol you have.
• Add Cyclomethicone at 5-8% to the Lipid phase to help the cream spread and absorb faster.
• Check the amount of Satin Cream Maker to ensure it is appropriate (1.5-2.0%) to achieve the desired thickness and stability.
• Mixing process:
  • Prepare the Water phase by dissolving water-soluble ingredients (including Satin Cream Maker) and stirring/mixing until a smooth gel-cream texture is obtained.
  • Prepare the Lipid phase by dissolving oil-soluble ingredients (including Cyclomethicone and the reduced amount of Kojic Acid Dipalmitate).
  • Gradually add the Lipid phase to the Water phase in small amounts while continuously mixing or stirring. Ensure both phases are at a similar warm temperature (around 70 degrees as recommended by the staff).
  • Once the cream starts to cool down, gradually add heat-sensitive ingredients such as Phenoxyethanol SA (Optiphen Plus) and essential oils/fragrances in the final step and mix thoroughly.

These adjustments should help you achieve a smoother, lighter, easier-to-spread, faster-absorbing cream without a rancid smell.

If you have any further questions or need to adjust the formula again, feel free to ask.