The sun, our favorite “frenemy”

The sun is necessary to life. It induces positive effects such as the promotion of vitamin D synthesis, melatonin synthesis which helps maintain the biological rhythms, and it has also been proven to positively influence the mood by promoting release of endorphins.

But the sun exposure brings also some negative short and long-term effects to the organism. The most known and visible one, sunburn, is linked to UVB. Shortly after exposure, reactional acne, summer Lucitis, or photosensitization can appear. In addition, it is also well known that repeated sun (and especially UVA) exposure can lead to photo aging associated symptoms such as dark spots, wrinkles, elastosis, and ultimately skin cancer.

The risks associated with sun exposure are therefore important enough to privilege proper protection from its rays.

What is photoprotection?

Photoprotection is ensured by suncare products, which are characterized by 3 distinct elements:

The SPF, or Sun Protection Factor, which indicates the product’s level of protection towards UVB rays;
The UVA performance, which is not evaluated in the same way depending on the area. In Europe, UVA performance should be at least 1/3 of the SPF, while in the UK, there is a specific evaluation system called BOOTS star rating. And in Asia, it is rated between PA+ and PA++++, from 2 to 16. On the contrary, it is not required in the US;
The broad spectrum performance, which is only mandatory in the US.

To bring an efficient photoprotection to the skin, suncare products contain UV filters. These particular cosmetic ingredients are divided into 2 categories:

Organic UV filters: this heterogenous group of complex molecules, in liquid or powder form, hydrophilic or lipophilic, bring UVA and/or UVB protection. They work by absorbing the UV rays at the skin surface, preventing their penetration.
Inorganic UV filters: these powders can be used already predispersed or not. There is only 2 of them: titanium dioxide, which protects against UVB, and zinc oxide, with broad spectrum efficacy. They work by reflecting UV rays at the skin surface or scattering them. During scattering, a particle will disperse the UV rays it receives onto those around, which will do the same, reducing the intensity of the rays.

Figure 1: UV protection mechanisms

But adding UV filters in a cosmetic formulation brings a lot of problems…

Performance first

The first objective of a suncare product is to be efficient. Organic and inorganic UV filters need to be carefully formulated to ensure an effective protection against UV rays.

If organic UV filters are used, the first thing to think of is proper solubilization. Each organic UV filter has a specific solubilizer. It is therefore necessary to identify the best combination by consulting the UV filter supplier’s documentation and then doing some experimental lab work (visual test, microscopy).

If inorganic UV filters are chosen, ensuring their good dispersion is crucial. For this, the use of a dispersing or wetting agent is necessary. Coated grades facilitate the compatibility, the dispersibility and the sensoriality of the UV filters.

Another tip is to combine organic and inorganic UV filters. The resulting synergy effect will increase the final SPF of the formula.

The use of other ingredients can help:

SPF boosters: increase the final SPF without increasing the total amount of UV filters in the formula
Photostabilizers: maintain UV filters performance after UV radiation

Finally, it is important to create a homogeneous film at the skin surface by choosing the right gelling agents and adding a film former.

Stability challenge

Stability is always a challenge for cosmetic products, and especially for suncare products because of UV filters. Fluid and sprayable ones are particularly difficult to stabilize.

The first thing to check is the packaging that will be used. Viscosity drop at high temperature (especially for beach products) can be a problem if the packaging is not adapted. Moreover, W/O formulas sometimes interact with some materials, leading to instabilities.

The choice of the right gelling system is primordial to guarantee a perfect stability. It depends again on the packaging used, but some gums may increase stability at high temperature.

Finally, the type of emulsions (W/O or O/W) and emulsifier play a key role in the formula stability. Depending on the type of UV filters used and the other ingredients of the formula, the emulsifier is more or less compatible and may no longer fulfil its emulsifying function.

Sensoriality is key

Sensoriality is not only essential to ensure a second purchase, but above all it favors regular application and proper skin protection. In sunscreens, organic and inorganic UV filters present sensorial disadvantages to overcome.

Organic UV filters bring greasiness, shine, tackiness, and a high film residue to final formulas. These drawbacks can be balanced by using powders, adding alcohol, adapting the emollients and feeling agents and using SPF boosters to reduce the total amount of UV filters and the quantity of oils.

Inorganic UV filters, on the other hand, increase formula dryness, roughness, and whitening effect if they are non-nano. Adapting the emollients and feeling agents improves the formulation afterfeel. As the emulsifying system impacts the product’s sensoriality, changing the emulsifier can also be a solution. Reducing the filters’ particle size or tinting the formula can counteract the whitening effect.

Gattefossé suncare expertise

Gattefossé’s ingredients for unexpected suncare products

Gattefossé has developed texture ingredients that respond to the major issues encountered in the formulation of suncare products: performance, stability, and sensoriality.

Emulium® Illustro, a W/O emulsifier, has proven its compatibility with organic, mineral UV filters and SPF boosters and creates stable formulations with a comfortable feel.

Emulium® Dolcea MB, an O/W emulsifier, creates stable textures with an ultra-soft and non-tacky afterfeel. In addition to its biodegradable nature, its moisturizing properties will benefit any sunscreen products.

Emulium® Mellifera MB is another O/W emulsifier that makes it possible to formulate suncare products with a light and non-greasy finish. Its capacity to auto-adapt to climates and its many different claims make it a perfect emulsifier for suncare applications with skincare benefits.

Finally, Acticire® MB is an active texturizing agent that improves sensoriality of suncare products by reducing the greasy and tacky afterfeel. It also improves durability of the protective film on the skin, as observed with the UV camera.

8 suncare formulas for all situations and needs

Gattefossé’s application lab has been working on 8 new formulations, with very different sensory profiles and containing organic UV filters, mineral or a combination of both, to meet all expectations in terms of photo-protection.

2177-7.03 Mineral Shield SPF50

Sensitive and sun-intolerant skin deserves effective and sensorial UV protection too! Formulated with Emulium® Illustro, this sunscreen is neither sticky nor greasy on the skin. It is easy to apply and gives the skin a sunshine glow thanks to Gatuline® Radiance.

2708-1.08 Refresh & Protect Bi-gel SPF30

Refresh and protect your skin with this sprayable suncare lotion. Thanks to Emulfree® CBG MB and its bi-gel technology, the formula is very fluid and refreshing during application and brings comfort without any greasy nor tacky afterfeel.

2746-1.17 Dry Touch Lotion SPF50

Perfectly adapted for beach or daily use, this suncare lotion SPF50 formulated with Emulium® Mellifera MB spreads easily and penetrates very quickly into the skin. It leaves a very light and dry feel, as if no product had been applied.

2532-2.01 High Protection Lotion SPF50

This very high protection SPF50 is the best ally for sun-sensitive skin, whether in the city or at the beach. Thanks to Emulium™ Dolcea MB, the texture is fluid, soft and comfortable and leaves a very smooth, non-greasy and non-sticky afterfeel.

2397-2.25 Extremely Soft Protection SPF30

This SPF30 sunscreen doesn’t look like it! Thanks to Emulium® Dolcea MB, the texture is soft and comfortable and leaves a very smooth, non-greasy and non-sticky afterfeel. It can be used for daily care routines or at the beach.

2494-1.13 Powdery Stick SPF50+

Some body areas are particularly prone to UV damage and deserve a foolproof sun protection: nose, cheekbones, scars, tattoos… This anhydrous sun stick is ideal due to its targeted application and its SPF50+. Once applied, it leaves a dry and powdery finish.

2078-1.13 Fully Mineral Sunscreen SPF30

This natural sunscreen SPF30, composed exclusively of non-nano mineral filters, is perfect for protecting your skin from UV rays at the beach while limiting environmental damage! Unlike most natural sunscreens, its texture is soft, easy to spread, and leaves no sticky nor greasy film thanks to Emulium® Illustro. A mix of active ingredients brings energy and radiance to the skin.

2670-1.12 Daily Shield SPF20

This daily care is perfect to protect the skin from UV rays without worry. Its comfortable yet fluid texture penetrates quickly and leaves a soft film on the skin, while Solastemis™ protects the skin from the harmful effects of UVA and combats photo-aging.

Find out more about these formulas in our booklet HERE.

Other formulations are available on demand. Do not hesitate to contact your Gattefossé’s sales representative for more information about these new formulations or for any suncare development project to benefit from Gattefossé’s expertise.

Formulation Finder

SELECT