The most important component of sunscreens, their "raison d'être", are the UV filters. Their job is to stop ultraviolet light from reaching the skin. UV filters can do this in one of two ways: they can either absorb the UV-light by "soaking it up"; or they can scatter it and reflect it away from the skin. Consequently, there are two different types of UV filter.
What are the different types of UV filters?
All UV filters are chemical substances which act as "sunscreens". They typically fall into two main categories: synthetic or organic filters, such as the cinnamates, which absorb UV light; and mineral or inorganic filters, such as titanium dioxide, which mainly reflect UV light. Frequently, both types are used in combination for optimum effect in a product.
Absorber filters (or organic filters)
Absorber type UV filters work by absorbing ultraviolet light much like a sponge soaks up water. Each tiny sunscreen "sponge" soaks up ultraviolet light, and then releases it back out after converting it into lower energy and less dangerous infrared light. These filters can be thought of as "energy converters", converting dangerous ultraviolet light into safer infrared warmth.
(Source: Cosmetic Toiletry & Perfume Association - CTPA)
Reflector filters (mineral or inorganic filters)
Unlike the absorber-type UV filters, reflectors tend to be less specific about the type of UV-light they reflect and tend to protect against both UVA and UVB. These sun filters act in a different way. Instead of soaking up the UV rays in the way that the absorber sun filters do, these materials reflect and scatter the UV light away from the skin without changing it to anything else. They can be thought of as thousands of tiny mirrors each reflecting UV light away from the skin.
(Source: Cosmetic Toiletry & Perfume Association - CTPA)
Organic and mineral sunscreens - Which is better?
Is one better? No, they just work in different ways.
The most commonly used UV filters are the absorbers because these are more efficient (you get more sun protection for the same amount of ingredient). However they are often supplemented with reflectors.
Some people with sensitive skins or certain allergies may prefer a product with less absorber-type (organic) filters. In order to ensure that the product still provides the required amount of UV-protection, the absorber filters are replaced with reflector (mineral) sunscreens. Allergy and reaction to sunscreens are very rare so the large majority of users find absorber-type sun filters suit their needs.
Organic sunscreens often get a bad press because they are sometimes referred to as "chemical sunscreens". There is a growing trend to see "chemical" as something of which to be scared - but this is just not the case.
Because different UV filters tend to be effective against different UV-light wavelengths most sun protection products include several different UV filters. This means they provide a broad spectrum of protection across the whole range of UV. Including different filters in a product also helps to achieve the high levels of sun protection that are demanded by consumers today.
One other thing to know about all sun filters is that many of them will not dissolve in water. This means that most sun products must contain oil ingredients to help dissolve the sun filters. Manufacturers try to keep the oil content to an absolute minimum to prevent the finished product from being greasy, but a small amount in the product is essential.
<< Previous Page <<:
What is Broad spectrum UV protection and why do I need it?