Sunscreen Cream Separation Issue

The separation of oil and water phases in your sunscreen cream is a common problem in emulsion formulations. This happens because the ingredients in the two phases are not compatible and cannot stay mixed together stably.

The solution to this problem is to use an emulsifier.

What is an Emulsifier?
An emulsifier is a substance that has both oil-attracting (lipophilic) and water-attracting (hydrophilic) parts in its molecule. This allows it to act as a bridge between the oil and water phases, helping them to mix and stay dispersed within each other, preventing separation. Emulsifiers work by surrounding the droplets of one phase (like oil droplets in water) and keeping them suspended in the other phase.

How to Choose and Use Emulsifiers:

1. Select the Right Type: Emulsifiers come in different types, primarily Oil-in-Water (O/W), where oil is dispersed in water (typical cream texture), and Water-in-Oil (W/O), where water is dispersed in oil (often heavier texture, used for water resistance). The choice depends on the desired type of sunscreen cream.
2. Use Appropriate Concentration: Each emulsifier has a recommended usage range. Using too much or too little can lead to an unstable formulation.
3. Consider Co-emulsifiers or Stabilizers: Sometimes, additional ingredients like co-emulsifiers or thickeners/stabilizers (such as certain polymers or gums) are needed to further enhance the stability and texture of the emulsion.
4. Manufacturing Process: The method of mixing, temperature, and stirring speed significantly impact emulsion stability. It's important to follow the recommended process for each specific emulsifier.

Examples of Emulsifiers You Could Consider:

• LeciCream™: A natural emulsifier derived from Hydrogenated Lecithin, suitable for heavy creams. It is mixed into the oil phase.
• Emulsifying Wax 1000: A non-ionic emulsifier (Cetearyl Alcohol (and) Ceteareth-20) that effectively binds water and oil. It's suitable for O/W creams and lotions and is mixed into the oil phase. It can also act as a thickener.
• CreamMaker EG™: Functions as both a thickener and stabilizer, helping the cream texture remain stable. It can also act as a binder/emulsifier and is mixed into the water phase.
• OccluSoft™: A Water-in-Oil (W/O) cationic emulsifier that provides a soft, non-sticky feel to W/O creams. It is mixed into the oil phase, and the water phase is added gradually.

To solve the separation issue, you need to choose an emulsifier that is compatible with the other ingredients in your formula and follow the correct mixing procedure.