FR2676645A1 - Novel cosmetic compositions for protecting the skin against UV radiation - Google Patents

Abstract

The invention relates to the discovery that a mixture composed of shea butter unsaponifiable and a bacterial filtrate of biotechnological origin enables the efficacy of sunscreen agents in a cosmetic preparation to be improved by increasing its coefficient of solar protection.

Description

The dermal dangers of prolonged exposure to the W-rays of the sun are now becoming better known.

To reduce the adverse effects of solar irradiation on exposed skin, chemical compounds have been developed based on their ability to absorb UVA and UVB radiation by specific chromophores. Certain highly efficient molecules and synergistic mixtures of these molecules have made it possible to increase the values of the sun protection indices considerably.

The cosmetics industry is contradictory in trying to increase the protection factors of its products and is increasingly hesitant to use too high concentrations of these filters, mainly because of their sensitizing and allergenic potential.

Research in cosmetology is therefore moving towards solutions that can provide better sun protection, while reducing the risk of irritation, allergy or phototoxicity.

The object of the present invention is the discovery of a combination of two active components: the unsaponifiable fraction of shea butter and the ultrafiltrate of the culture medium of a bacterial fermentation which has a power of potentiation of the filtering action conventional sunscreens.

The soothing and anti-inflammatory effect of shea butter, which is rich in terpene alcohols, has been described in numerous publications. Its use in cosmetics is also widespread.

The unsaponifiable fraction obtained by extraction after sodium treatment of shea butter is highly enriched in triterpene alcohols and phytosterols and plays a key role in anti-erythematous activity.

The bacterial fermentation filtrate has a stimulating activity on epidermal and dermal cells (stimulation of the growth of fibroblasts, of cellular respiration, regulation of seborrhea).

These properties have been highlighted on this product by the appropriate cosmetic objectification methods.

The filtrate is prepared from a culture medium of enterobacteria on various peptones, purified by decantation, filtration and other usual methods.

In the various tolerance and phototoxicity tests it has been discovered that the combination of the two active components leads to a better protection of the skin against the W rays.

The following tests were then carried out
Solar milks (formulas 1 to 4) containing an absorbent filter and / or a mixture of unsaponifiable shea butter and bacterial filtrate are applied to the skin of dehaired guinea pigs according to the official methods for determining the sun protection coefficients. .

<Tb>

<SEP> 1 <SEP> 2 <SEP> 3 <SEP> 4
<tb> Bees Wax <SEP><SEP> 0.50 <SEP> 0.50 <SEP> 0.50 <SEP> 0.50
<tb> Oil <SEP> of <SEP> lanolin <SEP> 5.00 <SEP> 5.00 <SEP> 5.00 <SEP> 5.00
<tb> Oil <SEP> of <SEP> Silicone <SEP> 3.00 <SEP> 3.00 <SEP> 3.00 <SEP> 3.00
<tb> Octyl Palmitate <SEP> 8.00 <SEP> 8.00 <SEP> 8.00 <SEP> 8.00
<tb> Stearate <SEP> of <SEP> glycerol <SEP> 1.50 <SEP> 1.50 <SEP> 1.50 <SEP> 1.50
<tb> PHB <SEP> of <SEP> methyl <SEP> 0.20 <SEP> 0.20 <SEP> 0.20 <SEP> 0.20
<tb> PHB <SEP> of <SEP> propyl <SEP> 0.10 <SEP> 0.10 <SEP> 0.10 <SEP> 0.10
<tb> Demineralized <SEP> Water <SEP> 77.50 <SEP> 70.50 <SEP> 74.00 <SEP> 67.00
<tb> Carbomer-934 <SEP> 0.40 <SEP> 0.40 <SEP> 0.40 <SEP> 0.40
<tb> Triethanolamine <SEP> 99 <SEP>% <SEP> 0.40 <SEP> 0.40 <SEP> 0.40 <SEP> 0.40
<tb> Propylene <SEP> Glycol <SEP> 3.00 <SEP> 3.00 <SEP> 3.00 <SEP> 3.00
<tb> Diazolidinyl Urea <SEP> 0.20 <SEP> 0.20 <SEP> 0.20 <SEP> 0.20
<tb> Association <SEP> of
<tb> two <SEP> components <SEP><SEP>}<SEP> ~ <SEP> 7.00 <SEP> ~ <SEP> 7.00 <SEP>
<tb> assets
<tb> Octyl methoxycinnamate <SEP> - <SEP><SEP> - <SEP><SEP> 3.50 <SEP> 3.50
<tb> Fragrance <SEP> 0.20 <SEP> 0.20 <SEP> 0.20 <SEP> 0.20
<Tb>
The results of these measurements are summarized in the following table

<tb> Solar <SEP> Milks <SEP> 2 <SEP> | <SEP> 2 <SEP> | <SEP> 3 <SEP>
<tb><SEP> Index of <SEP> Protection
<tb><SEP> Solar <SEP> O <SEP> 1.5 <SEP> 6.3 <SEP> 8.9
<Tb>
The same experiment on the skin of human volunteers leads to the following values

<tb> Solar <SEP> milks <SEP> 1 <SEP> 2 <SEP> 3 <SEP> 4
<tb><SEP> Index of <SEP> Protection
<tb><SEP> Solar <SEP> O <SEP> 0.2 <SEP> 3.0 <SEP> 4.0
<Tb>
It has also been observed that repeated application of the product prior to exposure to radiation increases the protection.

Thus, a pretreatment of 10 days before the measurement of sun protection index makes it possible to determine an index of 11.0 on the guinea pig model and of 4.8 on the human skin for milk 4. The percentages of increase of the protection compared to the reference milk, are similar (if we compare the guinea pig and human results) and show that the combination of the two active components produces a synergistic effect, since the measured index is greater than the sum of the individual indices.

The use in cosmetics, a mixture of unsaponifiable shea butter and a bacterial filtrate endowed with stimulating activity on the epidermal cells thus makes it possible to increase the protection provided by the filters against the harmful effects of the skin. Sun.

It is thus possible to reduce the amount of filters while maintaining a high sun protection factor, and thus reduce the risk of sensitization and allergy.

The effectiveness of the mixture which is the subject of the invention is not limited to octyl methoxycinnamate, the combination with other filters is also convincing, such as, for example, the derivatives of para-aminobenzoic acid, benzophenone, salycilates.

This list is not exhaustive.

In formulation tests, it has been observed that the best efficiency is obtained by preparing an emulsion of the unsaponifiable shea butter with the bacterial filtrate, in proportions ranging from 0.5: 2 to 2: 0.5, using nonionic emulsifiers. The emulsion thus prepared can be stabilized by the addition of polyacrylic gels, polysaccharides or other aqueous gels commonly used in cosmetics.

This combination of the two active components described can be advantageously used in any cosmetic or dermopharmaceutical product, gels, O / W or W / O emulsions, ointments. It is used not only in products for sun preparation, sunscreen products and after-sun products, but also in any cosmetic skincare product, which protects the skin during the day even from the weak radiation doses (normal daily exposure): day creams, foundations, make-up products, masks. This list is not exhaustive.

To be effective, it is recommended to mix the two active components, whose proportions can vary from 0.5: 2 to 2: 0.5 (by weight), from 1 to 90% in a finished cosmetic product. Below 1% there is no observable effect, beyond 90% it is impossible to stabilize the emulsion.

Claims (6)

1. Cosmetic and dermopharmaceutical compositions containing  one or more sunscreens and a non-absorbent product  potentiating the protective action of the filter (s).  2. Cosmetic and dermopharmaceutical compositions according to  claim 1 characterized in that this product  absorbing potentiator is a mixture of the fraction  unsaponifiable shea butter and a bacterial filtrate  obtained by fermentation culture.  3. Cosmetic and dermopharmaceutical compositions according to  any of claims 1 and 2 characterized in  what the respective proportion of the fraction  unsaponifiable shea butter and bacterial filtrate  is between 0.5: 2 and 2: 0.5.  4. Cosmetic and dermopharmaceutical compositions according to  any one of claims 1 to 3 characterized  in that the concentration of the active mixture is included  between 1 and 90% of the finished product. 5. Cosmetic or dermopharmaceutical compositions according to one  any of claims 1 to 4 characterized in that  the bacterial culture filtrate is obtained by  fermentation of enterobacteria on peptones, followed by  filtration of the fermentation medium and its purification. 6. Cosmetic or dermopharmaceutical compositions according to one  any of claims 1 to 5 characterized in that  they are gels, O / W emulsions or W / O emulsions,  makeup, ointments.