Addressing Bubbles in Your Sunscreen Formulation

It sounds like you've made a good attempt at creating the sunscreen based on the SPF Protect Ultra II formula! The issue with persistent bubbles in the cream texture is a common challenge in emulsion formulations and is typically caused by air being incorporated during the mixing process.

While Satin Cream Maker is known for its ability to help absorb bubbles, the method and duration of mixing are critical factors.

Looking at the recommended method for using SPF Protect Ultra II with Milk Lotion Maker and Satin Cream Maker, a key step involves adding the water phase to the oil phase while blending at high speed for at least 15 minutes. This long blending time is crucial for proper emulsification and helps to ensure a stable texture and potentially allows trapped air to escape or be managed by the emulsifiers.

Your method involved heating and combining the phases, then adding Satin Cream Maker, and finally the preservative. While your mixing speed of 1000-1200 rpm seems reasonable, the duration of blending during the critical emulsification step (when adding water to oil) might be the reason for the trapped bubbles.

To address the persistent bubbles, I recommend trying the following:

1. Follow the mixing method described in the SPF Protect Ultra II product description more closely.
2. Pay particular attention to the step where the water phase is added to the oil phase.
3. Ensure you are blending at a sufficient speed during this addition and continue blending for the recommended duration of at least 15 minutes.

By ensuring thorough and sufficiently long blending during the emulsification process, you should be able to achieve a smoother, bubble-free texture.