WO2016016540A2

WO2016016540A2 - Solar filter promoting agents

Info

Publication number: WO2016016540A2
Application number: PCT/FR2015/051981
Authority: WO
Inventors: Alexandra Fregonese; Alexandre EVEILLARD; Marie NAVARRO
Original assignee: Innovi
Priority date: 2014-07-18
Filing date: 2015-07-17
Publication date: 2016-02-04
Also published as: WO2016016540A3; FR3023715B1; FR3023715A1

Abstract

The invention relates to a synergistic combination of at least two agents promoting the photoprotective effectiveness of at least one solar filter, one of said two agents promoting the photoprotective effectiveness of the solar filter or filters against UVA, the other one of said two agents promoting the photoprotective effectiveness of the solar filter or filters against UVB, the agent promoting effectiveness against UVA being pongamol and the agent promoting effectiveness against UVB being chosen among hydroxycinnamic acids and the derivatives thereof. The invention also relates to the uses of such a combination in any solar composition.

Description

AGENTS PROMOTING SOLAR FILTERS

The invention relates to a synergistic combination of two or more promoters for the photoprotective efficacy of at least one sunscreen, one of the two agents being promoters of the photoprotective efficacy of the sunscreen or sunscreens vis-à-vis UVA, the other of the two agents being promoter of the photoprotective efficacy of the UVB sunscreen (s), its applications in cosmetology and dermatology for topical use, for the protection of the skin vis-à-vis vis-a-vis ultra-violet rays, but also in any other industrial field requiring the protection of a support vis-à-vis these rays, in particular to limit the aging of a coating when it is exposed to the sun.

There are three types of ultraviolet radiation, UVA with a wavelength of 400-320 nm, UVB with a wavelength of 320-280 nm and UVC with a wavelength of 280- 200 nm. Only UVA and UVB manage to cross the atmosphere, but UVAs represent between 95% and 98% of the UV that reaches the surface of the earth. The longer the UV radiation has a long wavelength, the closer it gets to visible light and the less harmful it is, but the greater its skin penetration power is important.

UVA by acting on melanocytes is responsible for tanning, but because of their high penetrating power, they cause the formation of free radicals which are responsible for the deterioration of lipids, proteins, collagen fibers and elastin fibers. UVB causes burns.

Solar products filter the UVB and leave, in part, penetrate the UVA, because these remained for a long time considered as not harmful.

The use of sunscreens is the most used cosmetic approach to fight against the damage caused by UV. The mode of action of these creams is based mainly on the ultraviolet filtration by chemical or physical filters (also called minerals).

Chemical filters are molecules that can absorb UV radiation. Thus, they operate on the same principle as melanin produced by animal cells in response to UV radiation.

Chemical filters are often aromatic compounds combined with a carboxyl group and are divided into three categories: UVA filters, UVB filters and UVA / UVB filters depending on their ability to absorb UVA and / or UVB radiation.

As non-limiting examples of chemical anti-UVA filters, the following can be cited: - benzophenone-8

benzophenone-3,

- meridimate,

benzophenone-4,

- avobenzone,

- terephthalylidene dicamphor sulfonic acid

- bisimidazylate

- Diethylamino-hydroxybenzoyl hexyl benzoate.

As non-limiting examples of UVB chemical filters, the following can be mentioned:

p-aminobenzoic acid (PABA)

- padimate 0,

phenylbenzimidazole sulphonic acid,

- cinoxate,

- homosalate,

octocrylene

- octinoxate,

octisalate

- trolamine salicylate,

4-methylbenzylidene camphor (4-MBC)

benzophenone-9,

octyl triazone

- amiloxate.

As non-limiting examples of UVA and anti-UVB chemical filters, the following can be mentioned:

- bisoctrizole,

- betotrizinol,

- Trisiloxane drometzole

- iscotrizinol.

Mineral or physical filters are compounds capable of reflecting and / or diffusing UVA and UVB radiation by forming an opaque film on the skin. These compounds may be, for example, zinc oxide, titanium dioxide, iron oxide, talc, or kaolin.

The sun protection or the photoprotective efficacy of a solar composition can be evaluated by measuring the sun protection factor, SPF (Sun Protection Factor, SPF) or protection index (IP). The protection index has the same meaning in all countries. It is determined by standardized tests. The method known in vitro method Diffey has many advantages and mainly an ethical advantage since it allows to test without subjecting the skin of a volunteer UV.

The protective efficacy evaluated in vitro of solar products is based on the spectrophotometric measurement of the absorption of the product applied to a substrate having a relief comparable to that of human skin. The effectiveness of the protection against UVA and UVB is then determined by calculation.

The method involves applying the test product to a plate and measuring with a spectrophotometer its absorbance between 290 and 400 nm (UVB and UVA). From the absorption spectrum the SPF is calculated according to the formula:

* <* * 'With Ελ the erythematogenic spectral efficiency, SA the irradiance j EA.SA.dA

cpp _" 290 solar spectral and TA the spectral transmittance of the sample. The effectiveness

^- 4i »

j ^"EA SA T _L erythemal spectral dA and solar spectral irradiance are data

^{"1 ("} >

from the literature. The functions EA, SA, as well as their product appearing in the numerators and denominators of the formulas.

In vitro SPF (or I P) is therefore the ratio between two areas calculated between 290 and 400 nm. An SPF index can therefore only be obtained by attenuating both UVB radiation and UVA radiation. A solar product therefore always contains both at least one anti-UVA filter and a UVB filter, which can also be the same if it is anti-UVA and anti-UVB.

To date, high performance sunscreen compositions having an SPF of up to 50 are available, but a high SPF value remains associated with a high content of filters in the solar composition. All filters, including those conventionally used and in particular certain chemical filters, are not totally harmless; as examples, some would turn out to be endocrine disruptors. We are still looking for solar compositions with high photoprotection, while having a low content of filters.

The Applicant has discovered that by combining a combination of one or more furanoflavones, and one or more phenolic acids and / or their derivatives, with at least one sunscreen, the efficiency of said filter is surprisingly increased. solar. Thus, the invention relates to a synergistic combination of at least two agents that promote the photoprotective efficacy of at least one sunscreen, one of the two agents being promoters of the photoprotective efficacy of the sunscreen (s) vis-à-vis UVA screw and being selected from furanoflavones, the other of said two agents being promoter of the photoprotective efficacy of the UVB sunscreen (s) and being selected from phenol acids and their derivatives.

By promoter agent, also called "booster" agent, the photoprotective efficiency of a sunscreen is understood to mean a compound which considerably increases the efficiency of the sunscreen. The promoters of the present invention may have an absorption spectrum in UVA or UVB, but they are not considered as sunscreens because they are not or too little effective alone. Their promoter role does not result from an addition of their absorbency to that of the filter or filters with which they are associated.

The promoters of the invention are furthermore in the interest of being natural in the case of furanoflavones, or phenol acids and their derivatives, they all come from the metabolism of phenylpropanoids, in plants. Phenylpropanoids are a class of organic compounds of plant origin whose common point is to be biosynthesized in plants from phenylalanine. According to the invention, said agents can of course be manufactured synthetically.

By way of illustration, the following diagram shows some examples of compounds derived from the metabolism of phenylpropanoids from phenylalanine.

10 As indicated above, the agent (s) promoting the photoprotective efficacy of one or more anti-UVA sunscreens are chosen from furanoflavones.

Furanoflavones are exclusively listed in plants belonging to the legume family. Any furanoflavone may be included in the composition of a combination of the invention. In particular, the following furanoflavones can be mentioned, extracted from Pongamia glabra or pinnata, Cassia fistula, Millettia sanagana: kanjone, karanjine, pongamol, pongapine, glabone, fistulaflavone and sanagone.

In addition, ingredients comprising a mixture of furanoflavones may also be included in the composition of a combination. This is the case, for example, with Karanja oil whose composition includes the following furanoflavones: karanjin, pongapin, kanjone, pongamol and glabone.

Pongamol is a preferred furanoflavone.

A combination of the invention may further comprise, as a promoter for the photoprotective efficacy of a solar filter with respect to UVA, compounds of the family of diarylheptanoides which are characterized by the presence of two nuclei aromatics linked by a linear chain of seven carbon atoms. As a preferred diarylheptanoid, curcumin can be retained.

According to the invention, the one or more agents which promote the photoprotective efficacy of one or more UVB sunscreens are chosen from phenol acids and their derivatives. Of these, hydroxycinnamic acids and their derivatives are preferred.

According to the invention, and as commonly accepted, the hydroxycinnamic acids include the methylated derivatives (O-CH ₃ ) of the phenolic hydroxyls.

Advantageously, the hydroxycinnamic acids are chosen from para-coumaric acid, caffeic acid, ferulic acid, sinapic acid, 3,5-dimethoxy cinnamic acid and 3,4-dimethoxy acid. cinnamic.

In addition to one or more hydroxycinnamic acids or hydroxycinnamic acid derivatives, a combination of the invention may include other phenolic acids

The term "phenol-acid derivatives" is understood to mean in particular the esters, amides, aldehydes and alcohols of these phenolic acids and in particular those of the hydroxybenzoic acids and of the hydroxycinnamic acids. Of the hydroxybenzoic acids, parahydroxybenzoic acid, protocatechic acid, vanillic acid, gallic acid, syringic acid, salicylic acid and gentisic acid are preferred.

Any ingredient or plant extract containing molecules belonging to the family of hydroxycinnamic acids may be used in a combination of the invention. For example:

- garlic, carrot and tomato extracts, rich in para-coumaric acid

- extracts of rice grains, wheat or oats, rich in ferulic acid.

Within the meaning of the invention, and as previously stated, the molecules which directly derive from the hydroxycinnamic acids can be used to carry out a combination of the invention. In this class of hydroxycinnamic acid derivatives, mention may be made of the following compounds:

esters of cinnamic acid or of chlorogenic acid, as well as esters of chlorogenic acids, chlorogenic acids including, in particular, caffeylquinic acid, ferulylquinic acid, p-coumarylquinic acid, sinapylquinic acid and dimethoxycinnamylquinic acid)

- amides of cinnamic acids, such as feruloyl-tyramine) - coumarines

- cinnamyl aldehydes

- cinnamyl alcohols

- lignin

Of the hydroxycinnamic acids, para-coumaric acid, caffeic acid, ferulic acid, sinapic acid, dimethoxy-3,5-cinnamic acid and 3,4-dimethoxy-cinnamic acid are preferred. .

As the examples below will illustrate, and it is an object of the invention, a preferred combination of the invention is that of pongamol and ferulic acid, as well as that of pongamol, ferulic acid para-coumaric acid.

In a combination of the invention, the ratio of the mass of the anti-UVA promoter agent (s) to the mass of the anti-UVB promoter agent (s) ranges from 0.1% to 99.9.

Advantageously, the promoters of a combination of the invention are mixed with a solubilizing agent and / or viscosity, the latter promoting synergy between said agents. Preferably, it is selected from associations of lipophilic compounds such as that marketed by the Applicant under the name of GPS ^® -guidage performance care, surface guidance, and which will be designated hereinafter by GPS-S. The person skilled in the art is of course able to choose another agent to solubilize the promoter agents.

The invention also relates to a composition comprising a combination as defined above, at least one sunscreen and a vehicle. As indicated above, a composition of the invention can find applications in any industrial field, in which the protection of a support, for example painted or varnished, is necessary or desirable.

The invention is of particular interest in the field of photoprotection of the skin. Thus, it relates to a cosmetic or dermatological composition for topical use comprising a combination of the invention, at least one sunscreen and a support that is acceptable from a cosmetic or dermatological point of view.

Whatever its destination, a composition of the invention comprises one or more sunscreens, in particular as defined above. These are chosen from UVA, anti-UVB and anti-UVA / UVB filters, chemical, physical and mixtures thereof, provided they contain at least one anti-UVA filter and at least one anti-UVB filter, the same filter can be anti-UVA and anti-UVB.

In a composition of the invention, the weight of the combination preferably varies from 0.1% to 20% relative to the mass of the composition. The mass of the anti-UVA filter (s) and the mass of the anti-UVB filter (s) advantageously vary from 0.1% to 50% and from 0.1% to 50%, respectively, relative to the mass of the composition.

The invention relates to the use of a synergistic combination as described above, in particular that of pongamol and at least one hydroxycinnamic acid, for increasing the photostability of UVA, UVB and / or UVA / UVB chemical sunscreens and / or physical. This combination is particularly effective in increasing the photostability of a combination of 2-ethylhexyl-p-methocinnamate and 1- [4-methoxyphenyl] -3- [4-tert-butylphenyl] propane-1,3-dione.

The present invention is now illustrated, without limitation, by the following examples in support of FIGS. 1-8, in which:

FIG. 1 represents spectrophotometric absorption curves of samples A, I and Y. Figures 2, 3 and 4 show spectrophotometric absorption curves of creams 1, 2, 3 and 4 of Example 3.

FIG. 5 represents the spectrophotometric absorption curve of the combination 1-8 of Table 2 solubilized in the GPS-S, of Example 4.

FIG. 6 illustrates the comparison of the SPF of the creams 1 and 2 of the example

4 (FC).

FIG. 7 illustrates the comparison of the SPF of the creams 1 and 2 of the example

5 (FP).

Figure 8 illustrates the interest of a combination of the invention in the photostabilization of a mixture of sunscreens.

Example 1 Preparation of Combinations of the Invention and Anti-UV Evaluation in Spectrophotometry

1) Combinations of pongamol and ferulic acid

Various combinations of the invention are prepared from pongamol as a UVA and ferulic acid protecting promoter as a UVB protection promoting agent.

The combinations are prepared by dry mixing of pongamol and ferulic acid, with proportions varying from 0-100% by weight relative to the total mass of the mixture, for each of these ingredients, as indicated in the following Table 1.

Table 1

M 50

N 55 45

0 60 40

P 65 35

Q 70 30

R 75 25

S 80 20

T 85 15

u 90 10

V 95 5

w 97.5 2.5

X 99 1

Y 100 0

Each combination is analyzed spectrophotometrically. All of them, including those containing only one of the two promoters (Samples A and Y) have a level of absorption in UVA and UVB. The optimal efficiency, ie the highest level of absorption for a maximum UVA / UVB ratio, is observed with sample I containing 30% pongamol and 70% ferulic acid.

2) Combinations of pongamol, ferulic acid and para-coumaric acid

On the basis of the results of Example 1-1 in which sample I exhibits the optimum efficacy, other combinations of the invention are prepared from pongamol as an anti-UVA promoter and ferulic acid and para-coumaric acid, as an anti-UVB promoter.

The combinations were prepared according to the same protocol as that described above. They are indicated in the following Table 2.

Table 2

Sample Pongamol Ferulic acid Para-coumaric acid

1 30 70 0

1-1 30 65 5

1-2 30 60 10

1-3 30 55 15

1-4 30 50 20

Each combination is analyzed spectrophotometrically. All have a level of absorption in UVA and UVB. The optimal efficiency, ie the highest level of absorption for a maximum UVA / UVB ratio, is observed with sample 1-8 containing 30% pongamol, 30% ferulic acid and 40% para-coumaric acid.

Example 2 Synergy of a Combination of an Anti-UVA Promoter and an Anti-UVB Promoter According to the Invention

The spectrophotometric absorption curves of pongamol alone (sample Y of Table 1 above), ferulic acid alone (sample A of Table 1 above), and the pongamol and ferulic acid combination of the sample I of Table 1 above, have been noted.

The measurement was performed on samples of said promoters diluted to 0.002% in alcohol.

The curves are shown in Figure 1.

It is unexpectedly observed that the absorption capacity of the combination of pongamol and ferulic acid is greater than the addition of the absorption capacities of each of pongamol and ferulic acid. There is therefore a synergy between these two promoters.

Example 3 Synergistic Action of the Promoter Agents of the Mixture in a Composition of the Invention

The following creams 1 to 4 were prepared with different chemical filter (CF) assays (2-ethylhexyl-p-methocinnamate and 1- [4-methoxyphenyl] -3- [4- tert-butyl phenyl] propane-1,3-dione, also called avobenzone) in the absence or in the presence of pongamol and / or ferulic acid:

- cream 1 - STANDARD: composed of 4.75% FC

- cream 2 - EVALUATION A: composed of 4.75% FC + 4.75% pongamol (in solubilized form in the GPS-S, at a rate of 16% (m / m))

- cream 3 - EVALUATION B: composed of 4.75% FC + 4.75% ferulic acid (in solubilized form in the GPS-S, at a rate of 16% (m / m))

- cream 4 - EVALUATION AB: composed of 4.75% FC + 4.75% pongamol and ferulic acid (Sample I in solubilized form in the GPS-S, at a rate of 16% (m / m))

The absorption curves are shown in FIGS. 2, 3 and 4. The SPF values obtained for the creams 1, 2, 3 and 4 are 12.8; 25.1; 21 and 31.5 respectively.

The synergistic action of the two anti-UV promoter agents makes it possible to obtain a solar protection promoter effect (measured by SPF) greater than that of the two agents separately.

Example 4 Evaluation of a Solar Composition of the Invention of Chemical Filters

Combination 1-8 of Table 2 is first solubilized in GPS-S, as solubilizing agent and / or viscosity, at 16% (w / w). Then it is diluted in alcohol to 0.01% (w / v), then an absorption measurement is performed spectrophotometrically. The absorption curve obtained from 280 nm to 400 nm is shown in FIG.

It is observed that the combination 1-8 at 0.01% has a significant absorption capacity in UVB and UVA. This combination, however, can not be considered as having insufficient anti-solar efficacy. Indeed, to achieve an SPF of 6, a composition should incorporate a rate of chemical and / or mineral filters of the order of 4% (m / m) on average. To achieve the same SPF, 14.5% (w / w) of sample 1-8 alone, which acts as a solar agent, should be included.

The SPF efficiency of this combination is therefore much lower than that of a filter whether chemical or mineral, and a combination of the invention can not be considered a sunscreen.

On the other hand when it is associated with chemical and / or mineral filters, its promoting effect is considerable. This effect is hereinafter illustrated by the comparison of two creams:

cream 1 (Control) is composed of 4.75% (m / m) of chemical filters (FC), (2-ethylhexyl-p-methocinnamate and 1- [4-methoxyphenyl] -3- [4-tert- butyl phenyl] propane-1,3-dione, also called Avobenzone).

- cream 2 (Evaluation + Booster) is composed of 4.75% (m / m) chemical filters (FC) above + 4.75% (m / m) of combination 1-8 in the state solubilized as described above.

The results are shown in Figure 6.

The addition of the combination 1-8 in a proportion equivalent to that of the chemical filters makes it possible to multiply the SPF by 4. It should be noted that the SPF is not increased of the same order in a cream containing 9.50% ( m / m) of said FCs.

The present invention, when it is added in equal parts to chemical filters makes it possible to multiply the sun protection (evaluated by the SPF) by 4. Example 5: Evaluation of a solar composition of the invention of physical filters

To highlight the promoter effect of combination 1-8 on physical filters, the two creams were prepared and compared with different physical filter assays and combination 1-8:

- cream 1 (Control): composed of 16% (m / m) of physical filters

(FP) (titanium dioxide)

cream 2 (Evaluation + Booster): composed of 16% (m / m) of said physical filters (FP) above + 16% (m / m) of the combination 1-8 in the solubilized state as described above.

The results are shown in Figure 7.

The addition of the combination 1-8 in a proportion equivalent to that of the physical filters makes it possible to multiply the SPF by 4. It should be noted that the SPF is not increased of the same order in a cream containing 9.50% ( m / m) of said FPs.

It emerges from Examples 4 and 5 that the promoter effect is indifferently observed with the physical and chemical filters.

The present invention therefore makes it possible to obtain a high sun protection with a small percentage of chemical and / or physical filters by increasing the effectiveness of these.

On the other hand, the multiplying coefficient is not dependent dose: the SPF does not increase linearly with the increase of the addition of the reference sample. Not being dependent dose the invention can be considered as UV filter only but only as a booster.

It is up to the formulators to dose the chemical and / or mineral filter according to the targeted SPF and the multiplying coefficient provided by the booster.

Example 6: Light stabilizing action of a synergistic combination of promoter agents according to the invention in a composition of the invention.

By absorbing UV, the chemical (or organic) filters pass into an excited state, this phenomenon being reversible or not. The return to the initial state passes by the emission of a low energy radiation which is generally translated by a release of heat.

However, it can also result that after the solar exposure of an organic filter, its composition is modified and, consequently, its UV absorption capacity is also. This parameter therefore has a direct impact on the photoprotective efficiency of a sunscreen.

The ability of a filter to maintain its photoprotective efficacy during exposure to UV radiation is determined by its photostability.

Thus, the combination of 2-ethylhexyl-p-methocinnamate and 1- [4-methoxyphenyl] -3- [4-tert-butylphenyl] propane-1,3-dione filters (also called Avobenzone), under the effect of ultraviolet radiation exhibits an irreversible photoreaction photoreaction. This instability makes the use of this combination ineffective vis-à-vis the photoprotection.

On the other hand, when this same combination is used with a synergistic combination of the invention, it is observed that the respective photoprotective capacity of each of the filters is retained. This effect is hereinafter illustrated by comparing the photostability of two creams:

Cream 1: STANDARD: composed of 4.75% (w / w) of a mixture of 2-ethylhexyl-p-methocinnamate and 1- [4-methoxyphenyl] -3- [4-tert-butylphenyl] propane-1,3- dione.

- Cream 2: EVALUATION composed of 4.75% (m / m) of a mixture of 2-ethylhexyl-p-methocinnamate and 1- [4-methoxyphenyl] -3- [4-tert-butylphenyl] propane-1,3- dione and 4.75% (w / w) of the combination 1-8 of Table 2 first solubilized in the GPS-S, as a solubilizing agent and / or viscosity, at a rate of 16% (m / m). m)

The results are shown in Figure 8. The addition of the combination 1-8 in a proportion equivalent to that of the chemical filters makes it possible to make photostable (photostability greater than 70%) the combination of the chemical filters 2-ethylhexyl-p-methocinnamate and 1- [4-methoxyphenyl] 3- [4-tert-butylphenyl] propane-1,3-dione, demonstrating a further interest in a synergistic combination of the invention.

Claims

A synergistic combination of at least two agents promoting the photoprotective efficacy of at least one sunscreen, one of the two agents being promoters of the photoprotective efficacy of the sunscreen or sunscreens vis-à-vis the UVA, l other of said two agents being promoter of the photoprotective efficacy of the UVB sunscreen or sunscreens, characterized in that the agent promoting the efficacy against UVA is pongamol and agent promoting the efficacy against UVB is chosen from hydroxycinnamic acids and their derivatives.

2. Combination according to claim 1, characterized in that the hydroxycinnamic acids are chosen from para-coumaric acid, caffeic acid, ferulic acid, sinapic acid, 3,5-dimethoxy cinnamic acid. and 3,4-dimethoxycinnamic acid.

3. Combination according to any one of the preceding claims of pongamol and ferulic acid.

4. Combination according to any one of the preceding claims, pongamol, ferulic acid and para-coumaric acid.

Combination according to any one of the preceding claims, characterized in that the ratio of the mass of the anti-UVA promoter agent (s) to the mass of the anti-UVB promoter agent (s) varies from 0.1% to 99.9%. %.

6. Combination according to any one of the preceding claims, characterized in that said promoter agents are solubilized in a solubilizing agent and / or viscosity promoting synergy between said agents.

7. Composition comprising a combination according to any one of the preceding claims, at least one sunscreen and a vehicle.

8. Cosmetic or dermatological composition for topical use comprising a combination according to any one of claims 1 to 7, at least one sunscreen and a cosmetically or dermatologically acceptable carrier.

9. Composition according to claim 7 or 8, characterized in that the sunscreen or filters are selected from UVA filters, UVB and UVA / UVB, chemical, physical and mixtures thereof.

10. Composition according to any one of claims 7 to 9, characterized in that the mass of the combination varies from 0.1% to 20% relative to the mass of the composition.

11. Composition according to any one of claims 7 to 10, characterized in that the mass of the anti-UVA filter (s) and the mass of the filter (s) anti-UVB range from 0.1% to 50% and from 0.1% to 50%, respectively, based on the weight of the composition.

12. Use of a synergistic combination according to any one of claims 1 to 6 for increasing the photostability of chemical and / or physical UVA, UVB and / or UVA / UVB sunscreens.

Use according to claim 12 for increasing the photostability of a combination of 2-ethylhexyl-p-methocinnamate and 1- [4-methoxyphenyl] -3- [4-tert-butylphenyl] propane-1,3- dione.