Formula Review and Recommendations

Your goal is to create a facial gel targeting wrinkles (minor), clogged pores, acne marks, clarity, and smooth skin for combination skin. Your initial formula includes several excellent ingredients for these concerns.

Let's address your specific questions:

1. Gel viscosity: Your original formula used 2% Pro Polymer. Pro Polymer is a strong gel maker, and 2% can result in a quite thick, potentially "หนืดไป" (too viscous) gel, especially for a facial product where a lighter feel might be preferred for combination skin. The staff's suggestion to reduce Pro Polymer to 1% is appropriate. You can always start lower and add more if you desire a thicker texture.
2. Unnecessary or incompatible ingredients:
   • Based on your goals and skin type, the staff's suggestion to remove Tea Tree Oil (Water Soluble) is reasonable. While Tea Tree Oil is great for killing bacteria associated with inflammatory acne, it is less effective for clogged pores, which you specifically mentioned.
   • Similarly, for combination skin, Double Hyaluron Liquid might provide more moisture than needed, especially in the T-zone. The staff's recommendation to focus on ingredients that balance moisture is suitable for combination skin.
   • The ingredients you selected are generally compatible in a water-based gel formula. However, the concentration of Phenoxyethanol in your original formula (0.15%) is below the typical recommended range (0.5-1.0%) for effective preservation. It is crucial to use a sufficient amount of preservative to prevent microbial growth and ensure product safety and stability. Increasing it to at least 0.5% is highly recommended.
3. Adenosine addition timing: You asked if Adenosine Complex should be added after gel formation because it might thin the gel. The staff correctly explained that adding it after the gel is formed is often easier, especially without high-speed mixing equipment. This allows the gel-forming ingredient (Pro Polymer) to hydrate fully and build viscosity first. While it might slightly reduce viscosity, this can often be compensated for by adjusting the gel maker concentration. If you have a high-speed mixer, the order is less critical, but adding heat-sensitive ingredients after cooling is always a good practice.
4. Last ingredient (Preservative vs. Adenosine): The staff's explanation is accurate. If any heat is used during the formulation process, heat-sensitive ingredients like Phenoxyethanol (avoid heat over 80°C) and potentially Adenosine Complex (storage in refrigerator suggests some heat sensitivity or preference for cooler temperatures) should be added after the mixture has cooled down. If no heat is used, the order between these two is less critical, as long as they are fully incorporated.

Revised Formula Recommendation:

Considering your goals, combination skin, and the staff's valuable input, here is a revised formula that should be more effective and stable:

• Repair Activator™: 10%
• Matrixyl™ 3000: 6%
• Galactomyces Ferment Filtrate (Pitera): 4%
• GlucoBright™ (Acetyl Glucosamine): 4%
• Safe-B3™ (Vitamin B3, Niacinamide): 5%
• Adenosine Complex: 1.5%
• Pro Polymer™: 1%
• Phenoxyethanol: 0.5%
• Water: 68%

This revised formula removes ingredients less targeted to your specific acne concern (clogged pores) and skin type (combination moisture balance), increases the concentration of a key multi-benefit ingredient (Safe-B3™), adjusts the thickener for better texture, and ensures proper preservation.