Analysis of Your Sunscreen Formula

Thank you for sharing your sunscreen formula and skin concerns. Let's break down the feasibility and suitability of your proposed cream.

Formula Feasibility

Your formula consists of Avobenzone (5%), Octisalate (5%), Octocrylene (10%), Light Cream Maker™ (2%), and Water (78%). The total concentration of chemical sunscreens is 20%, which is a common level for achieving good SPF protection and is within the maximum usage rates for these filters in Thailand (Avobenzone 5%, Octisalate 5%, Octocrylene 10%).

Your proposed mixing method involves heating the sunscreens (Avobenzone, Octisalate, Octocrylene) to help dissolve the Avobenzone, then adding the Light Cream Maker™, and finally the water. This method is feasible. Avobenzone requires heat to dissolve properly in the oil phase (which in your case are the other liquid sunscreens). While Light Cream Maker™ is described as working without heat, it can be added to the oil phase, and the heat applied is primarily for dissolving the sunscreens, not activating the emulsifier. The emulsifier will then work to combine the heated oil phase with the water phase.

Therefore, yes, this formula can be made using the ingredients and method you described.

Suitability for Your Skin Type

Your skin is described as combination to oily, prone to clogged pores, large pores, and sensitive.

• Oily/Combination/Large Pores: The formula uses Light Cream Maker™, which is designed to create a light, non-greasy texture. However, a total of 20% oil-soluble chemical sunscreens is a relatively high oil load. While the emulsifier helps, the final feel might still be heavier than ideal for very oily skin and could potentially contribute to a feeling of clogged pores for some individuals.
• Clogged Pores/Acne: Chemical sunscreens themselves don't necessarily cause acne, but the overall formulation can. A heavier or occlusive formula might worsen clogged pores. The lightness of the base is key here, but the high sunscreen percentage is a factor to consider.
• Sensitive Skin: Chemical sunscreens, especially at higher concentrations, can sometimes cause irritation or stinging on sensitive skin. While Avobenzone, Octisalate, and Octocrylene are generally better tolerated than some older filters, individual sensitivity varies. Your formula does not include any ingredients specifically aimed at soothing or calming sensitive skin.

In summary, while the formula is feasible to make, it might not be optimally suited for your specific skin concerns (very oily, acne-prone, sensitive) due to the high concentration of chemical sunscreens and lack of ingredients targeting these issues.

Suggested Adjustments

To make the sunscreen more suitable for your skin type, consider these adjustments:

1. Add Soothing and Anti-inflammatory Ingredients: Incorporate ingredients known to calm sensitive skin and reduce redness, such as Allantoin, Panthenol (Vitamin B5), or extracts like Centella Asiatica.
2. Include Ingredients for Oily/Acne-Prone Skin: Consider adding Niacinamide, which can help regulate oil production, improve pore appearance, and strengthen the skin barrier. For clogged pores, Salicylic Acid (BHA) is effective, but incorporating it requires careful attention to pH and compatibility within the formula.
3. Optimize the Base: While Light Cream Maker™ provides a light feel, you might explore other emulsifiers or formulation techniques specifically designed for very light, non-comedogenic sunscreens for oily and acne-prone skin. However, working with your current ingredients, ensuring thorough mixing with Light Cream Maker™ is crucial for the best texture.
4. Consider Sunscreen Concentration/Type: If you find the 20% chemical sunscreen load too heavy or irritating, you might explore formulations with a slightly lower total sunscreen percentage or consider incorporating physical sunscreens (Zinc Oxide, Titanium Dioxide), which are often better tolerated by sensitive skin, although formulating chemical and physical filters together requires careful consideration of compatibility and stability (especially with Avobenzone).

By incorporating ingredients that address oiliness, clogged pores, and sensitivity, you can create a sunscreen that is not only protective but also more comfortable and beneficial for your specific skin type.