Evaluation of Your Sunscreen Formulation

You've proposed a sunscreen formula aiming for a non-greasy, long-lasting, waterproof, sweat-resistant texture without white cast, suitable for combination/oily skin. Let's break down the ingredients and method.

Ingredient Analysis

Based on the properties of the ingredients:

• LipidSoft Lite, Silicone Gel (Ultra Clear), and Cyclomethicone are excellent choices for creating a light, non-greasy feel and improving spreadability. Cyclomethicone, in particular, is known for its quick evaporation, which helps reduce the heavy feel often associated with sunscreens.
• Water-Capsule is a key component here. It's a water-in-oil (W/O) emulsifier designed to create formulas that are long-lasting, waterproof, and sweat-resistant, while minimizing the greasy feel typically associated with W/O emulsions by allowing for a lower oil percentage. This aligns well with your goals for durability and water resistance.
• Beige Iron Oxides Easy Mix is a coated pigment that provides color and helps with adherence and waterproof properties.
• Satin Cream Maker is primarily an oil-in-water emulsifier and thickener. In this W/O formula, it appears to be used to thicken the water phase before emulsification, which is a valid technique to help stabilize the internal water phase in a W/O system.
• SPF Protect Plus (at 20%) is the ingredient that might work against your goal of a non-greasy texture, especially for oily skin. As noted in the feedback you received, this ingredient is likely oil-based. A high percentage of an oily component can make the final product feel heavy or greasy.

Mixing Method Review

Your proposed mixing method is appropriate for creating a water-in-oil emulsion using Water-Capsule:

1. Combining the oil-soluble ingredients (LipidSoft Lite, Silicones, Iron Oxides, SPF Protect Plus) with the Water-Capsule emulsifier forms the oil phase.
2. Combining the water (Distilled Water) with the Satin Cream Maker forms the thickened water phase (gel).
3. Adding the oil phase to the water phase all at once and stirring slowly is the correct procedure for emulsifying with Water-Capsule to form the W/O cream.

Achieving Your Goals

• Non-greasy texture: The formula includes several ingredients that promote a light feel (LipidSoft Lite, Silicones). However, the oiliness of SPF Protect Plus at 20% is the main factor that could make the formula feel greasy on oily skin.
• Long-lasting, Waterproof, Sweat-resistant: The use of Water-Capsule as a W/O emulsifier and coated Iron Oxides strongly supports these properties. The formula is likely to be durable and resistant to water and sweat.
• No white cast: This depends on the specific SPF Protect Plus. If it contains physical filters (Titanium Dioxide, Zinc Oxide), it might leave a white cast, although the Beige Iron Oxides will help tint the product. Chemical sunscreens generally do not leave a white cast.
• Suitable for combination/oily skin: The base formula with light emollients and silicones is a good starting point, but the choice of sunscreen active is critical.

Recommendation for Oily Skin

To ensure a non-greasy texture suitable for combination/oily skin, it is highly recommended to replace SPF Protect Plus with a less oily sunscreen active. Good alternatives include:

• Tris-Biphenyl Triazine (Nano): This is a highly effective broad-spectrum chemical filter that can provide high SPF/PA at a reasonable concentration (e.g., 10% can yield SPF 30+). It's compatible with the oil phase and generally contributes less to a greasy feel compared to some other sunscreen oils.
• Physical Filters (Titanium Dioxide and Zinc Oxide): If you prefer physical sunscreens, use modern, coated, and properly dispersed forms (like Titanium Dioxide Nanosil or suitable Zinc Oxide dispersions) in the oil phase. The existing Beige Iron Oxides will help minimize white cast.

By adjusting the sunscreen active, this formula has the potential to achieve a light, non-greasy, long-lasting, waterproof, and sweat-resistant finish suitable for oily skin. The mixing method is appropriate for the W/O system.