Formula Review for Thick Serum Texture

Based on your formula and the properties of the ingredients, this formulation should indeed yield a thick serum texture as you desire. The ratio of Silky Serum Base (30%) to the water phase (Part B, totaling 69%) is appropriate for achieving a thicker consistency, similar to a heavy cream, while still maintaining the quick-absorbing feel characteristic of the Silky Serum Base.

Regarding the staff's feedback, their point about Vitamin E (Tocopheryl Acetate) at 1% potentially causing stickiness is valid. The product information for Vitamin E (Tocopheryl Acetate) indicates that usage rates above 0.5% can lead to a sticky feeling on the skin. Reducing the concentration to 0.5%, as suggested by the staff, would help mitigate this stickiness while still providing antioxidant benefits.

The mixing method you described, slowly adding Part B to Part A and then incorporating Part C, is a suitable approach for formulating with Silky Serum Base.

In summary:

• The ratio of Silky Serum Base to the water phase is suitable for a thick serum texture.
• Using 1% Vitamin E (Tocopheryl Acetate) may result in a sticky feel; reducing it to 0.5% is recommended for a lighter texture.
• The mixing method is appropriate.

Consider adjusting the Vitamin E concentration based on your desired skin feel.