Sunscreen is an emulsion which can be either oil-in-water or water-in-oil. To create it, you must prepare an oil phase and a water phase separately, then mix and heat them. Homogenization is a key process to guarantee that the product will have the right consistency. When manufacturing sunscreen, give special attention to protection against UV filters.
Tell us about your production challenge
Ultraviolet types – why do we need protection from them?
While three types of UV radiations (UVA, UVB and UVC) exist, sunscreens’ ingredients only protect us from two: UVA and UVB. UVA goes deeper in the skin and is photoaging, meaning that skin gets old prematurely because of exposure to it. It can also damage collagen, elastin and hyaluronic acid, which are produced in this deeper layer. UVB only reaches the top part of your skin and is responsible for getting the pigment, but is also the one that can cause skin cancer. UVC, the most harmful of the three, doesn’t “trespass” the ozone layer – so it doesn’t reach us, luckily.
Do the math for the sunbath
Ever wondered what are the numbers on the sunscreen bottles? That’s the SPF, or the Sun Protection Factor. It is the result of a simple math that determines how long it takes for your skin to get red due to sun exposure. You calculate it running tests with UVB, one of the three different ultraviolet (UV) radiation types. Apart from SPF, European sunscreens usually also have a PPD factor. Meaning “persistent pigment darkening”, it’s the equivalent to SPF for UVB.
Back to math, the SPF number on the bottle is the amount of radiation it takes to make your skin red using the sunscreen versusthe amount it takes without the sunscreen. Translating into English, it means that with an SPF 50 sunscreen, you need to get exposed 50 times longer to the sun to get burned compared to being exposed without the product.
PPD, in its turn, indicates the sunscreen efficiency protecting you from longer-lasting tanning caused by UVA. Like SPF, PPD compares the effect with the sunscreen and without it. It’s important because high exposure to UVA can cause erythema.
Different filters: how to make sunscreen?
To make sunscreen, you can use chemical, physical or mixed filters, which are the main components of sunscreen and the ones that protect you from radiation. Chemical filters absorb part of the photon energy of the radiation and turn it into heat. This makes us feel hot for 20 to 30 minutes after applying the product. Chemical sunscreen types also have a lighter consistency.
Physical filters don’t absorb, rather reflect part of the radiation, and leave a white coating on the skin. Some producers try to avoid them due to esthetics. They also include nanoparticles which help spread the product better. Some scientists, though, raised questions regarding whether they can cause damage and penetrate the skin.
To get the most efficiency, you can combine both chemical and physical filters to get a safe and photostable product. Make sure you include protection from UVA and UVB.