Discover what you need to have the perfect emulsion in your formula.
The facts prove that exposure to the sun causes most skin cancers. Dermatologists recommend the use of sunscreen and/or sunblock to protect you from the harmful effects of the Sun. As the usage of Sunscreens has increased and become common practice, the number of different formulas and brands has increased. There are a variety of options, such as water-resistant, infant, various sun protection factors (SPF), organic, and inorganic ingredients.
Sunscreen Manufacturing Process
The manufacturing process of sunscreen/sunblock involves a process of combining two ingredients that do not easily mix to create an emulsion. The emulsion can be water in oil or oil in water. Typical sunscreen ingredients include zinc oxide or titanium dioxide, which reflect UV rays and avobenzone or oxybenzone, which absorb UV rays. Other common ingredients include emollients (smoothing agents), lubricants, emulsifiers, perfume, color, and preservatives.
Manufacturing Process Phases:
- Water Phase: includes the addition of the active UV filters and emulsifiers mixed into the water phase.
- Oil Phase: includes the addition of various oil products and minor ingredients.
- The water and oil phases are then blended together into a homogeneous solution to create an emulsion (with a target droplet size of 1-3 µm to create a stable emulsion).
Common Conventional Mixing Technology Challenges
There are common challenges of using conventional mixing technologies (Co-axial Agitator with or without Scrape Surface Agitator):
- Gums and thickeners are difficult to mix without lumps or agglomerates.
- Partially hydrated materials build up on mixer shafts.
- The ideal emulsion is difficult to manufacture.
- Need to micronize the active UV filter ingredients to obtain maximum utilization of the ingredients.
- Long batch times.
- Significant air entrainment.
Solutions for sunscreen mixing applications.
When mixing oil and water (two ingredients that normally repel each other) along with other ingredient substances, it can be hard to achieve a stable smooth and glossy solution. The solutions below will produce a smooth, stable emulsion.
- Our first recommendation is to install a Scott Turbon Top Mount High Shear Mixer or Bottom Mount High Shear Mixer. These unique mixer heads will rapidly disperse, dissolve, hydrate, de-agglomerate, disintegrate, homogenize, and emulsify the most difficult ingredients.
Should the existing tank and Co-axial Agitation System not have the capability to be retrofitted with a high shear mixer without replacing the existing mixing system, Scott Turbon would recommend the following:
- An alternative recommendation is to install a High Shear Mill (HSM) in recirculation with the processing vessel. The process involves mixing the water phase in the Co-axial system (adding the UV filters and gums) while recirculating through the HSM. The oil phase is then transferred to the Water phase to create the Emulsion.
These solutions are proven to create a superior high-gloss smooth emulsion. Contact us to hear our success stories.
Advantages of the Scott Turbon Mixer Equipment
- Eliminates lumps and agglomerates with the proper dispersion of the gums providing maximum yield.
- Able to reduce the UV filters down to their natural micronized size for maximum UV effect with multi-row design.
- Creates a water in oil or oil in water emulsion in the 1-3µm range.
- Able to use the existing mixing tank with minimal additional cost for the inline mixer.
- Reduction in overall production time.