Cosmetic Formulation Advice

Based on your formula using Silky Serum Base, Titanium Dioxide, Zinc Oxide, and Water, here is the information regarding waterproofness and coloring:

Waterproofing

Your formula uses Silky Serum Base, which creates a water-in-silicone base. This type of base can offer some water resistance. However, to achieve good waterproofness, additional ingredients are needed.

To enhance the waterproof properties, you can add:

• Polyethylene Wax (around 3%): This wax helps to form a coating on the skin, improving the formula's water resistance and stability.
• Dimethicone or Silicone Gel (3-5%): These silicone ingredients also contribute to film formation and water repellency, helping the product stay on the skin better.

Coloring to a Base Tone

To color your cream to a skin tone (base color), you will need to use cosmetic pigments. The most common pigments for creating skin tones are:

• Iron Oxides Yellow
• Iron Oxides Red
• Iron Oxides Black

You will need to blend these pigments in varying ratios to match the desired skin tone. Titanium Dioxide, which is already in your formula for UV protection, also acts as a white pigment and contributes to the coverage and opacity of the base color.

These pigments are typically dispersed in the oil or silicone phase of the formula.