METHOD FOR EVALUATING THE PROTECTION RATE OF AN ACTIVE INGREDIENT AND ACTIVE INGREDIENT POSSESSING THE PROTECTION RATE THUS EVALUATED AGAINST VISIBLE LIGHT-INDUCED PIGMENTATION
Patent Information
- Application Number
- FR2021010966
- Authority / Receiving Office
- FR · FR
- Patent Type
- Patents
- Current Assignee / Owner
- Filing Date
- 2021-10-15
- Publication Date
- 2025-03-21
- Estimated Expiration
- 2041-10-15
Abstract
Description
Title of the invention: METHOD FOR EVALUATING THE PROTECTION RATE OF AN ACTIVE INGREDIENT AND ACTIVE INGREDIENT HAVING THE PROTECTION RATE THUS EVALUATED AGAINST VISIBLE LIGHT-INDUCED PIGMENTATION FIELD OF THE INVENTION
[0001] The invention relates to a method for measuring the protective effect or the protection rate against hyperpigmentation induced by visible light, of active ingredients and cosmetic or pharmaceutical composition, a method for selecting active ingredients and ecobiological cosmetic or pharmaceutical composition having significant visible light filtration properties, in order to reduce the formation of pigment spots, and the ecobiological compositions thus selected. STATE OF THE ART
[0002] So-called visible light is composed of wavelengths ranging from 400 to 800 nm. According to some authors, the limits of this range can be different, the lower limit being between 320 and 480 nm, and the upper limit being between 720 and 880 nm.
[0003] In the spectrum of electromagnetic radiation, visible light is surrounded by UV rays (below 400 nm), and by infrared rays (above 800 nm).
[0004] Visible light contains all the colors of the rainbow, ranging from blue, the most energetic, to red, the least energetic, through green and yellow.
[0005] However, it has been shown that visible light is very important in hyperpigmentation problems. For example, irradiation of volunteers with phototypes III to IV with blue light (415 nm) induces pigmentation. On the other hand, red light (630 nm) does not induce pigmentation (Duteil et al. Pigment Cell Melanoma Res 2014 Sep; 27(5): 822-6) https: / / pubmed.ncbi.nlm.nih.gov / 24888214 /
[0006] Furthermore, in patients with melasma, the use of a tinted very high sun protection composition (SPF 50+) is significantly more effective in protecting against melasma relapses compared to a non-tinted very high sun protection product (SPF 50+) (Boukari et al., J Am Acad Dermatol, 2015 Jan; 72(1): 189-190) https: / / pubmed.ncbi.nlm.nih.gov / 25443629 /
[0007] Finally, more recent research suggests that receptors located at the Opsin 3 receptors in melanocytes play a key role in the induction of pigmentation by visible light. This receptor absorbs short wavelengths of visible light, up to 465 nm (Regazzetti et al., J Invest Dermatol., 2018 Jan; 138(1): 171-178).https: / / pubmed.ncbi.nlm.nih.gov / 28842328 /
[0008] In 2021, a protection index against visible light was established: the VL-PF (Visible Light-Protection Factor), or IP-VL in French (Index of Protection against Visible Light) (Duteil et al, Photodermatol Photoimmunol Photomed., 2017 Sep; 33(5): 260-266) (https: / / pubmed.ncbi.nlm.nih.gov / 28602025 / ).
[0009] This index is given by the following equation:
[0010] [Math.l] jp treated slope &ITA°prociuit
[0011] ITA° means Individual Typology Angle, calculated from spectro-colorimeter measurements of the L* (Luminance) and b* (yellow / blue color) components according to the formula:
[0012] [Math.2]
[0013] AITA° is defined as the difference between 1TTA° measured at a given time on the area exposed to visible light, and 1TTA° measured at the same time, on the area having received the same treatment, but not having been exposed to visible light.
[0014] This method has several disadvantages.
[0015] Even if the IP-VL gives a value of 1 for an irradiated but untreated area, and higher for irradiated areas but treated with effective products, it does not allow the effectiveness of these products to be compared with a non-irradiated area, or a irradiated but completely protected area.
[0016] Finally, the IP-VL also does not define a logical scale, easily understood by users, which would allow them to quickly judge the effectiveness of a product.
[0017] Finally, this method requires irradiating the backs of 20 volunteers for 4 days, and to carry out colorimetric measurements of their backs for 5 days. This method therefore has limits in terms of time and cost of implementation which is not compatible with the carrying out of screenings (of compositions or ingredients likely to be included in compositions), or rapid evaluations of numerous candidates with the aim of preselecting the most promising. AIMS AND TECHNICAL PROBLEMS OF THE INVENTION
[0018] A main object of the invention is to solve the technical problem of to provide a method for measuring the protection or protection rate against hyperpigmentation induced by visible light, in particular blue light, of active ingredients and cosmetic or pharmaceutical compositions.
[0019] Another main aim of the invention is to solve the technical problem of providing a method for selecting active ingredients and cosmetic, dermatological or pharmaceutical compositions having significant filtering properties of visible light, in particular blue light, in order to reduce the formation of pigment spots, and to allow easy comparison between different active ingredients or different compositions thus evaluated.
[0020] Another main aim of the invention is to solve the technical problem of providing a method for selecting active ingredients and cosmetic, dermatological or pharmaceutical compositions having significant filtering properties of visible light, in particular blue light, whether this selection is carried out in vivo or in vitro.
[0021] Another main object of the invention is to solve the technical problem of providing a technical solution for detecting and selecting active ingredients for topically use having the ability to filter visible light, and in particular blue light, significantly.
[0022] Again, a main aim of the invention is to solve the above technical problems according to a simple, rapid and inexpensive technical solution, making it possible to significantly improve the filtering capacity of visible light, in particular blue light, of topical compositions, usable on an industrial scale. Detailed description of the invention
[0023] The inventors have developed a method which allows, after irradiation of the backs of volunteers for 4-5 days, and application of active ingredients or compositions containing them and colorimetric measurements for 1 to 5 days, to calculate a protection index against visible light, in particular blue light; this index is expressed as a percentage, it varies between 0 (no protection) and 100% (protection with clothing for example).
[0024] It allows the effectiveness of these products, active ingredients or compositions to be compared between a treated and irradiated area and a non-irradiated area, or an irradiated area, which can be treated but is completely protected. It allows the products to be classified and the effectiveness of a composition to be quickly judged.
[0025] According to a first aspect, the invention relates to a method for evaluating the protection rate of a cosmetic active ingredient or of an ecobiological, cosmetic or dermatological composition containing said cosmetic active ingredient, against pig nutrition induced by visible light, in particular by blue light, characterized in that: a) A surface of the skin to be protected is identified and at least four areas are selected on this surface, a first area not treated with the cosmetic active ingredient or the composition and not exposed to light, called the control area, a second area not treated with the cosmetic active ingredient or the composition but exposed to light, a third area treated with the cosmetic active ingredient or the composition and not exposed to light, and a fourth area treated with the cosmetic active ingredient or the composition and exposed to light, for which the skin color is measured by measuring the ITA°, b) The cosmetic active ingredient or the composition containing it is applied to only the said third area, and the said fourth area, every day for 1 to 4 days, c) said second zone and said fourth zone are irradiated with a light source, comprising mainly visible light and at least blue light, for 1 to 7 days, d) The skin color of the said four areas is measured every day by a measurement of 1TTA° for 1 to 7 days, e) A protection rate is calculated according to the formula:
[0026] [Math.3] BLP“ 100 x(l slope &lTA“.product --------------------------) slope
[0027] In which: ITA° means Individual Typology Angle, calculated from spectro-colorimeter measurements of the L* (Luminance) and b* (yellow / blue color) components according to the formula:
[0028] [Math.4] I f S .s? 't । ' p ' ' y?
[0029] The A ITA ° product of the numerator is defined as the difference between 1TTA° measured at a given time on the fourth zone, and 1TTA° measured at the same time on the third zone. The A ITA ° n(m trajté of the denominator is defined as the difference between 1TTA° measured at a given time on the second zone, and 1TTA° measured at the same time on the first zone. Slope A ITA 0 pmdait is the slope of the ITA°p'or / / / / 7 curve as a function of time. Slope A ITA ° treat is the slope of the ITA°«^ treat curve as a function of time. time.
[0030] In an advantageous embodiment, the color is measured for 1 to 5 days and the slopes are measured between D1 and D5, or between D1 and D2 and D5, or between D1 and D3 and D5, or between D1 and D4 and D5, or between D1 and D2 and D3 and D5 or between D1 and D2 and D4 and D5, or between D1 and D3 and D4 and D5.
[0031] According to a particular embodiment of the invention, this method is characterized in that the cosmetic active ingredient or the composition containing it is modified and steps a. to e. are repeated in order to determine which cosmetic active ingredient or which composition containing it increases the BLP in order to increase its concentration so that said BLP reaches at least 50%.
[0032] According to a second aspect, the invention relates to a method for evaluating the protection rate of a cosmetic active ingredient or of an ecobiological, cosmetic or dermatological composition containing said active ingredient, against pigmentation induced by visible light, in particular by blue light, characterized in that it comprises: (a) the formulation of the active ingredient or composition containing it, in a test composition having a rheology compatible with spreading on a flat in vitro test surface; b) applying the in vitro test composition to a first in vitro test plate, of composition suitable for receiving irradiation with a UV-visible simulator and allowing the absorbance to be read, for example a polymer plate, in particular a polymethylmethacrylate (PMMA) at a thickness suitable for the in vitro test; c) the application to a second in vitro test plate of the same composition as the first plate called “Control Plate” for the measurement of the “background noise” of a suitable quantity of an in vitro control composition having a rheology compatible with spreading on a flat in vitro test surface, said composition not containing any active ingredient capable of filtering visible light and containing for example an alcohol, a polyglycol, in particular glycerol. d) drying the plates for 15 minutes in the dark and at room temperature; e) possible irradiation of the plates at 600W / m2 with a UV-visible simulator in order to possibly suppress the absorbance of unstable compounds in visible light; f) reading the absorbance at wavelength i denoted “Abi” of the test plate between 400 and 700 nm after insertion into a UV-Visible spectrophotometer (e.g. Lambda 650S, Perkin Elmer, MA, USA); g) reading the “background noise” absorbance noted Ci of the Control Plate described in c) between 400 and 700 nm; h) For each wavelength denoted “i”, the net absorbance denoted Ai is the result of “Ai = Abi-Ci”; i) The Blue Light Protection Factor, denoted BLP, is calculated by applying any of the following methods: I. For i from 418 to 420 nm, the Blue Light Protection Factor is calculated as applying the formula BLP = * V^420 / i 10¼ 10'^' ); with 0.12 < x < 0.39, avanta-A ^=418(1 2 / geusementx = 0.25847; or IL For i from 400 to 468 nm, the Blue Light Protection Factor is calculated as applying the formula BLP = * y / -468 / |G 11 io ' \ ; with 0.005 < 37 < 0.018, avanta-3 ^ / =400(1 2 ) geously 37 = 0.01168; or III. For i at 420 nm, the Blue Light Protection Factor is calculated by applying the formula BLP = 0 _ 10¼20^; with 0.39 < - < 1.16, advantageously = 0, 77663.
[0033] According to a particular embodiment of the invention, this in vitro evaluation method is characterized in that it comprises: a) the formulation of the cosmetic active ingredient or composition containing it, in a composition having a rheology compatible with spreading on a flat surface; b) applying the composition to a first polymethylmethacrylate (PMMA) plate (for example Helioplate PMMA Molded HD6, HelioScreen, Creil, France) at a rate of 1.3 mg / cm2 on the rough face; (c) the application of 15 microliters of glycerol on a second separate plate called “Control Plate” for the measurement of “background noise”; d) drying the plates for 15 minutes in the dark and at room temperature; e) irradiation of the plates at 600W / m2 with a UV-visible simulator (e.g. Suntest CPS+, Ametek, PA, USA) for a sufficient period of time, e.g. 5 to 15 minutes, to possibly suppress the absorbance of unstable compounds in visible light; f) reading the absorbance at a wavelength i, noted “Abi”, of the plates between 400 and 700 nm after insertion into a UV-Visible spectrophotometer (for example Lambda 650S, Perkin Elmer, MA, USA); g) reading the “background noise” absorbance noted Ci of the Control Plate described in c) between 400 and 700 nm; h) For each wavelength denoted “i”, the net absorbance denoted Ai is the result of “Ai = Abi-Ci” i) The Blue Light Protection Factor (or BLP) is calculated by applying any of the methods: I. The absorbance At of the composition to be evaluated is measured at a wavelength of 418 to 420 nm and the Blue Light Protection Factor is calculated by applying the formula BLP = 1 _ 10¼ x being between 0.12 and 0.39 or X 2 / II. The absorbance Aj of the composition to be evaluated is measured at a wavelength of 400 to 468 nm and the Blue Light Protection Factor is calculated by applying the formula BLP = * y«=468 / i0 \+ 10 t+1 \ y being between 0.005 and 0.018 or > ^=40011 2 / III. The absorbance A of the composition to be evaluated is measured at a wavelength of 420 nm and the Blue Light Protection Factor is calculated by applying the formula: BLP = ? ( 1 - 10 A*20), z being between 0.39 and 1.16
[0034] According to another particular characteristic of the invention, the method is characterized in that the active ingredient or the composition containing it is modified until a level of protection against visible light greater than 50%, in particular greater than 60%, even better greater than 70% is obtained.
[0035] More specifically, the invention also relates to a method for adjusting the protection rate of a cosmetic active ingredient, or of an eco-biological, cosmetic or dermatological composition containing it, the value of which measured according to one of the 2 methods described above is less than 50%, consisting of changing the cosmetic active ingredient, modifying its concentration or modifying the composition containing it until a protection rate of at least 50% is reached, measured according to one of the 2 methods described above.
[0036] In a particular embodiment, the adjustment method consists of changing the cosmetic active ingredient, modifying its concentration or modifying the composition containing it until a protection rate of 70%, advantageously at least 60%, is reached, measured according to one of the 2 methods described previously.
[0037] According to yet another particular characteristic of the invention, the evaluation method or the adjustment method is characterized in that the cosmetic active ingredient is chosen from Titanium Dioxide, Iron Oxide, Magnesium Oxide, Manganese Oxide, Manganese Dioxide, Calcium Oxide, Chromium Oxide, Calcium Cerium Oxide, Cerium Oxide, Clay Ore Oxide, Zinc Cerium Oxide, Barium / Calcium / Silicon / Titanium Oxide, Zirconium Dioxide, Cupric Oxide, Cuprous Oxide, Tin Oxide, Tungsten Oxide, or Germanium Dioxide.
[0038] According to a third aspect, the invention relates to a method for selecting a cosmetic active ingredient, or a cosmetic or dermatological ecobiological composition containing it, comprising the following steps: - determination of the protection rate of the cosmetic active ingredient or the composition containing it according to one of the 2 methods previously described, - selection of the cosmetic active ingredient or the composition containing it having a BLP protection rate of at least 50%, in particular at least 60% and even better at least 70%, noted respectively BLP 50 or BLP 50+, BLP 60 or BLP 60+, BLP 70 or BLP 70+.
[0039] According to yet another particular characteristic of the invention, the selection method is characterized in that the cosmetic active ingredient is chosen from Titanium Dioxide, Iron Oxide, Magnesium Oxide, Manganese Oxide, Manganese Dioxide, Calcium Oxide, Chromium Oxide, Calcium Cerium Oxide, Cerium Oxide, Clay Ore Oxide, Zinc Cerium Oxide, Barium / Calcium / Silicon / Titanium Oxide, Zirconium Dioxide, Cupric Oxide, Cuprous Oxide, Tin Oxide, Tungsten Oxide, or Germanium Dioxide.
[0040] According to a fourth aspect, the present invention also relates to a cosmetic active ingredient or a composition containing it protecting against hyperpigmentation induced by visible light, in particular blue light, characterized in that it has a BLP measured by the evaluation method as previously defined or described in the following description greater than 50%, in particular greater than 60%, even better greater than 70% noted respectively BLP 50 or BLP 50+, BLP 60 or BLP 60+, BLP 70 or BLP 70+.
[0041] The invention also relates to a cosmetic active ingredient or cosmetic or dermatological eco-biological composition containing it for use as a skin protective agent against visible light, in particular blue light, said cosmetic active ingredient or the composition containing it having a level of protection against visible light, in particular blue light, determined according to one of the 2 methods previously described, at least equal to 50%, in particular at least equal to 60%, advantageously at least equal to 70%, these compositions being respectively denoted BLP 50 or BLP 50+, BLP 60 or BLP 60+, BLP 70 or BLP 70+.
[0042] According to a particular embodiment, the cosmetic active ingredient is characterized in that it is chosen from Titanium Dioxide, Iron Oxide, Magnesium Oxide, Manganese Oxide, Manganese Dioxide, Calcium Oxide, Chromium Oxide, Calcium Cerium Oxide, Cerium Oxide, Clay Ore Oxide, Zinc Cerium Oxide, Barium / Calcium / Silicon / Titanium Oxide, Zirconium Dioxide, Cupric Oxide, Cuprous Oxide, Tin Oxide, Tungsten Oxide, or Germanium Dioxide.
[0043] According to a fifth aspect, the present invention also relates to an ecobiological, cosmetic, dermatological, or pharmaceutical composition, characterized in that said composition consists of one or more cosmetic or active ingredients pharmaceutical whose PLB is evaluated by the evaluation or selection method as previously defined or described in the following description, and in that this PLB is at least equal to 50%, in particular at least equal to 60%, even better at least equal to 70%, the designations of the ecobiological compositions in question being respectively noted BLP 50 or BLP 50+, BLP 60 or BLP 60+, BLP 70 or BLP 70+.
[0044] According to a sixth aspect, the present invention also relates to the use of the cosmetic active ingredient or the composition containing it, the PLB of which is evaluated by the evaluation or selection method as previously defined or described in the following description, and in that this PLB is at least equal to 50%, in particular at least equal to 60%, even better at least equal to 70% for the production of an ecobiological composition, usable in cosmetics, dermatology or pharmacy, protecting the skin against hyperpigmentation induced by visible light, in particular by blue light. The designations of the ecobiological compositions in question are respectively noted BLP 50 or BLP 50+, BLP 60 or BLP 60+, BLP 70 or BLP 70+.
[0045] According to a seventh aspect, the present invention finally relates to a cosmetic care method characterized in that the cosmetic active ingredient or the ecobiological or dermatological composition containing it, defined previously or in the following description, is applied to at least one area of the skin of a person at risk of hyperpigmentation upon exposure to visible light, this area of the skin is in particular chosen from an area of healthy skin, an area of scarred skin, an area of skin having lost its integrity, for example due to acne, atopy, eczema.
[0046] In the context of the invention, the Blue Light Protection Factor (PLB or FPLB or FPB) or Blue Light Protection Factor (BLP or BLPF or BPF) is a new index, a new scale, which gives a percentage of protection against pigmentation induced by visible light in general and by blue light in particular.
[0047] [Math.5] BLP = 100 x(l - slope &ITA°product slope 1A not treated
[0048] ITA° means Individual Typology Angle, calculated from spectro-colorimeter measurements of the L* (Luminance) and b* (yellow / blue color) components according to the formula:
[0049] [Math.6]
[0050] The A ITA ° product of the numerator is defined as the difference between 1TTA' measured at a given time on the fourth area treated with the "test product" and exposed to visible light, and the ITA° measured at the same time on the third area having received the same treatment, but not having been exposed to visible light. TheAITAonnon-treated of the denominator is defined as the difference between HTA0 measured at a given time on the second untreated area but exposed to visible light, and HTA0 measured at the same time on the first untreated control area and not having been exposed to visible light.
[0051] This blue light protection factor can be measured by an in vivo method, but the inventors have also developed a physical, in vitro method, allowing much faster screenings. Indeed, the inventors were able to correlate physical in vitro measurements with in vivo results on volunteers. This method, which is very interesting in terms of time and cost of implementation, therefore becomes totally compatible with the performance of screenings, rapid evaluations of numerous active ingredients or substances or compositions, with the aim of preselecting the most promising ones.
[0052] The percentage of visible light stopped between b (blue) and r (red) (in nm) is given by the formula: 1 y^-V. m ' - m :i rh ^i=b \ - / Aj is the absorbance of the product measured for wavelength i.
[0053] The data obtained by the invention make it possible to determine that: BLP = q - i <) * » lo j. for an absorbance measured between 418 and 420 nm; the value of this coefficient (0.25847) can vary in practice between 0.12 and 0.39; or BLP = ()()1 108]F / =46^| JLÏXIL™ j- for an absorbance measured between 400 and 468 nm; the value of this coefficient (0.01168) can vary in practice between 0.005 and 0.018; or BLP = g 77663^1 - ] 0^420^ for an absorbance measured at 420 nm; the value of this coefficient (0.77663) can vary in practice between 0.39 and 1.16.
[0054] The invention makes it possible to quantify the effectiveness of cosmetic active ingredients, products or compositions for preventing pigmentation induced by visible light, in the form of a percentage, on a scale ranging from 0 to 100%.
[0055] Classes allow the grouping together of active ingredients, products or compositions whose effectiveness is similar, and allow a more understandable presentation of the effectiveness of the active ingredients, products or compositions.
[0056] Finally, the results of this BLP index show a very good correlation with visible light absorption data obtained in vitro, which makes the use of this faster and less expensive method possible to predict the in vivo efficacy of products.
[0057] It is thus understood that the invention achieves the aforementioned aims by solving the technical problems stated above according to a simple technical solution usable on an industrial scale.
[0058] Visible light (400-700 nm) is a source of photodermatosis and hyperpigmentation, particularly around the wavelengths of blue light (450 nm). It is possible, by a rapid test of a few days, on volunteers, to measure the skin coloration obtained and to identify the most protective formulations against these hyperpigmentations.
[0059] It is possible to calculate a protection rate against hyperpigmentation induced by visible light, in particular blue light, expressed in %, using a simple formula which is based on the differences observed between "with" and "without" protection. This rate is called: - Visible Light Protection Factor FLV or FPLV or FPV; or - Blue Light Protection Factor or PLB or FPLB or FPB (or BLP or BLPF or BPF in English).
[0060] By measuring the induced hyperpigmentation, it is possible to classify cosmetic active ingredients, products or compositions, from the least protective to the most protective. Active ingredients, products or compositions which have a FPLB greater than 50% will be considered as having significant protection against the effects of blue light.
[0061] Furthermore, the inventors have demonstrated the correlation between the tests on volunteers and the in vitro tests, which allows access to a very rapid calculation of the FPLB from a series of simple measurements. This method therefore makes it possible to carry out very rapid and effective screening tests, usable on an industrial scale.
[0062] By using these different new methods, the inventors were able to show that certain topical compositions could have a BLP greater than 50%, or even greater than 60%, or even greater than 70%, which provides excellent protection against hyperpigmentation induced by visible / blue light.
[0063] How to calculate a “Percentage of protection against hyperpigmentation induced by visible light” or, alternatively, a “Percentage of protection against hyperpigmentation induced by blue light” also called “Blue Light Protection Factor”:
[0064] [Math.7] BLP = 100 x (1 - ■treated slope'
[0065] The selection of formulas according to their GLP makes it possible to produce ecobiological formulations to combat photodermatoses and hyperpigmentation induced by visible light in general, and by blue light in particular.
[0066] The extension of this technique to the active ingredients of cosmetic and pharmaceutical compositions allows the identification of the active ingredients of the formulation, generally reflective particles, which have an effect on this protection, and their use in compositions intended to be marketed for this property.
[0067] The invention will be further understood by various exemplary embodiments given simply by way of illustration and which therefore cannot in any way limit the scope of the invention. In the examples, all percentages are given as percentages by weight, the temperature is room temperature where is given in degrees Celsius, the pressure is atmospheric pressure, unless otherwise indicated.
[0068] EXAMPLES OF THE INVENTION Example 1: Evaluation of protection against pigmentation induced by visible light of 6 cosmetic formulations by an in vivo method on volunteers
[0069] The following formulations are made. The name of the substances used is given according to their INCI name. The composition values are given in grams per 100 grams. [Table 1] Oil phase: AB c DEF BIS-ETHYLHEXYLOXYPH NOL METHOXYPHENYL TRIAZINE 5% 2.5% 2.5% 2% 2% 2% BUTYL METHOXYDIBEN-ZOYLMETHANE 0% 5% 4.5% 0% 0% 0% DIETHYLAMINO HY- DROXYBENZOYL HEXYL BENZOATE 9% 0% 0% 4% 4% 4% DIETHYLHEXYL BUTAMIDO TRIAZONE 0% 0% 0% 3% 3% 3% ETHYLHEXYL SA-LICYLATE 4.5% 0% 0% 0% 0% 0% ETHYLHEXYL TRIAZONE 4.5% 0% 0% 0% 0% 0% HOMOSALATE 9% 0% 0% 0% 0% 0% METHYLENE BIS- 0% 6% 6% 3.5% 3.5% 3.5% BENZOTRIAZOLYL TETRA-METHYLBUTYLPHENOL [NANO]
[0070] [Table 2] Aqueous phase: A B c D E F AQUA / WATER / EAU : qsp 100 qsp 100 qsp 100 qsp 100 qsp 100 qsp 100 CAPRYLOYL GLYCINE 0,4% 0% 0% 0% 0% 0% CAPRYLYL GLYCOL 0,15% 0% 0,3% 0,25% 0,25% 0,25% DIPROPYLENE GLYCOL 0% 6% 0% 0% 0% 0% DISODIUM EDTA 0. % 0,2% 0% 0% 0% 0% GLYCERIN 2% 0% 0% 0% 0% 0% METHYLPROPANEDIO L 0% 0% 2% 0% 0% 0% PENTYLENE GLYCOL 0% 0% 0,5% 2% 2% 2% PHENOXYETHANOL 0% 0,35% 0% 0% 0% 0% POTASSIUM CETYL PHOSPHATE 0% 2% 0% 3% 3% 3% PROPANEDIOL 5% 0% 5% 2% 2% 2% SODIUM LAUROYL GLUTAMATE 0,1% 0% 0% 0,1% 0,1% 0,1% SODIUM POLY-ACRYLATE 0,75% 0% 0% 0% 0% 0% SODIUM STEAROYL GLUTAMATE 1% 0% 1% 0% 0% 0% SUCROSE LAURATE 1,5% 0% 0% 0% 0% 0% XANTHAN GUM 0% 0,3% 0,3% 0,2% 0,2% 0,2%
[0071] [Table 3] Poudres et pigments : A B C D E F IRON OXIDES (CI 74491, CI 77492, CI 77499) 0% 0,2% 1,8% 2,2% 4,1% 4,9% SILICA 2% 0,8% 6,0% 1,6% 1,6% 1,6% TITANIUM DIOXIDE (CI 77891, [NANO]) 1,9% 0,2% 4,9% 15,9% 14,0% 13,2%
[0072] The phases are prepared independently and are heated to 60°C with moderate stirring (planetary or Raynerie type) until homogeneous preparations are obtained. The phases are then combined with very vigorous stirring at 60°C (Ultraturax type) for 15 minutes, then allowed to cool to room temperature with moderate stirring. A - Control cream B - Cream with filters C - Cream II with filters D - Protection with BLP IE - Protection with BLP II F - Protection with BLP III.
[0073] The formulas are then evaluated for their ability to block pigmentation induced by visible light in a single-center, double-blind, randomized and controlled study, with intra-individual comparisons, on the backs of 20 volunteers. After 3 weeks of follow-up, all volunteers are irradiated (or not on certain areas) every day for 4 days using a dose of 144 J / cm2 of visible light (Oriel 1600 Watts solar simulator model 92292-1000 equipped with a metal mirror to exclude the vast majority of UVA and B rays). The compositions to be tested are applied (2 mg / cm2) to separate areas every day for 4 days. Skin color (parameters L, a and b) is measured by a Minolta CR400 Chromameter (Konica-Minolta, Osaka, Japan) and the ITA° angle is calculated according to the formula:
[0074] [Math. 8] MM* ™ wte i । s -.........\ x' ■ / S'
[0075] These values are then edited in the form of a curve (ITA as a function of time in days) and the slope “DITA°” is calculated between points D1 and D5, or between D1 J2 and D5, or D1 J3 and D5, or D1 J4 and D5, or D1 J2 J3 J5, or D1 J2 J4 and D5, or D1 J3 J4 J5.
[0076] From these calculations, the blue light protection factor known as BLP can be calculated for each formula tested by applying the formula:
[0077] [Math.9]
[0078] BLP=100x(l- slope &11 A !Wn treated The results, measured between several times (kinetics) for each formulation, are as follows: [Tables4] Composition Applied None ABCDEF BLP (D1-D2-D3-D4-D5) 0 10 15 48 61 66 66 D1-D5 0 10 16 48 62 68 66 D1-D2-D5 0 9 15 48 60 68 65 D1-D3-D5 0 10 16 48 62 68 66 D1-D4-D5 0 10 16 49 62 67 66 D1-D2-D3-D5 0 9 15 48 61 68 66 J1-J2-J4-J5 0 10 15 48 61 66 66 J1-J3-J4-J5 0 10 16 49 62 67 66
[0079] In view of the results, it is possible to say that compositions A, B and C do not have significant protection against pigmentation induced by visible light because their BLP is less than 50%. With 61%, 66% and 66% inhibition, formulations D, E and F are, on the other hand, compositions which significantly reduce pigmentation induced by visible light.
[0080] This effective protection is attributed to the presence of active ingredients whose concentration is significantly higher than that of formulas A, B and C, namely iron oxides (Iron Oxide), and titanium dioxide (Titanium Dioxide).
[0081] Example 2: Evaluation of protection against pigmentation induced by visible light of cosmetic compositions by an in vitro physical method
[0082] The formulations of Example 1 are evaluated for their ability to block pigmentation induced by visible light, by an in vitro physical method, by measuring their absorbance A at different wavelengths (denoted "i") and by calculating the protection factor against blue light, as indicated below:
[0083] Each sunscreen product was spread in 16 points by a robot (HD-SPREADMASTER, HelioScreen, Creil, France) on three polymethylmethacrylate (PMMA) plates (Helioplate PMMA Molded HD6, HelioScreen, Creil, France) at a height of 1.3 mg / cm2
[0084] on the rough surface. After drying for 15 minutes in the dark and at room temperature, the PMMA plates were irradiated at 600W / m2 (equivalent to 1 DEM for a phototype III) with the UV-visible simulator (Suntest CPS+, Ametek, PA, USA), in order to possibly suppress the absorbance of unstable compounds in visible light. After an irradiation period sufficient to deliver 600W / m2, the plates were inserted into the Lambda 650S UV-Visible spectrophotometer equipment (Perkin Elmer, MA, USA) for a reading between 400 and 700 nm after irradiation. Each plate was measured 9 times, and the result is given by the average of these 9 measurements. Before the measurement of the sunscreen, a PMMA plate was manually covered with 15 μL of glycerin and was measured by the spectrophotometer in order to subtract the absorption noise of the PMMA plate. Similarly, a metal plate was measured to estimate the total absorption of the support. The BLP is then measured using each of the three techniques below: a. For a wavelength reading i of 418 to 420 nm, the Blue Light Protection Factor is calculated by applying the formula BLP = 0 75847^^^(1- 10 iU * j ' For a value of this coefficient (0.25847) between 0.12 and 0.39, the measured variations remain acceptable within the framework of the invention; or b. For a reading of wavelength i from 400 to 468 nm, the Blue Light Protection Factor is calculated by applying the formula BLP = 0.0116^31-^ ,-Æ ; for a value of this coefficient (0.01168) included
[0085] between 0.005 and 0.018, the measured variations remain acceptable within the scope of the invention; or c. For a reading of the wavelength i at 420 nm, the Blue Light Protection Factor is calculated by applying the formula BLP = q 77663^1 - 10 ^420} ' for a value of this coefficient (0.77663) between 0.39 and 1.16, the measured variations remain acceptable within the framework of the invention. The results are as follows: [Tables 5] Applied Composition None ABCDEF BLP according to the volunteer test of example 1 0 10 15 48 61 66 66 BLP according to a 0 14 11 53 56 62 63 BLP according to b 0 15 10 52 56 62 64 BLP according to c 0 14 10 53 56 62 63
[0086] It can be seen that the results are consistent and similar to each other. The method developed therefore makes it possible to carry out composition and substance screenings much more quickly than with the techniques usually used. As in example 1, ecobiological compositions D, E and F are shown by this method to be the most significantly effective in blocking the effects of visible light on skin pigmentation.
[0087] Also, this effective protection is attributed to the presence of the active ingredients indicated in Example 1, namely iron oxides and titanium dioxide.
[0088] Example 3: Evaluation of protection against visible light-induced pigmentation of cosmetic substances and compositions by an in vitro physical method
[0089] The following formulations are made. The name of the substances used is given according to their INCI name. The composition values are given in grams per 100 grams. G: Protection with B LP X H: Protection with B LP XI I: Protection with BLP XII J: Protection with BLP XIII
[0090] [Table 6] Oily phase: GHIJ DIBUTYL ADIPATE 15 15 15 15 DIETHYLAMINO HYDROXYBENZOYL HEXYL BENZOATE 4 4 4 4 METHYLENE BIS-BENZOTRIAZOLYL TETRAMETHYLBUTYLPHENOL [NANO] 3.5 3.5 3.5 3.5 DIETHYLHEXYL BUTAMIDO TRIAZONE 3 3 3 3 BIS-ETHYLHEXYLOXYPHENOL ME-THOXYPHENYL TRIAZINE 2 2 2 2
[0091] [Table 7] Aqueous phase: GHIJ AQUA / WATER / EAU qs 100 qs 100 qs 100 qs 100 qs 100 CORN STARCH MODIFIED 2 2 2 2 PENTYLENE GLYCOL 2 2 2 2 PROPANEDIOL 2 2 2 2 XANTHAN GUM 0.25 0.25 0.25 0.25 SODIUM LAUROYL GLUTAMATE 0.1 0.1 0.1 0.1 SODIUM HYDROXIDE 0.1 0.1 0.1 0.1
[0092] [Table 8] Powders and pigments: GHIJ TITANIUM DIOXIDE [NANO] 7.6 7.6 7.6 14.0 IRON OXIDES (CI 77492) 0 0 3.0 0 IRON OXIDES (CI 77491) 0 0.7 0 0 IRON OXIDES (CI 77499) 0.4 0 0 0
[0093] The aqueous and oily phases are prepared independently and are heated to 60°C with moderate stirring (planetary or Raynerie type) until homogeneous preparations are obtained. The phases are then combined with very vigorous stirring at 60°C (Ultraturax type) for 15 minutes, then cooled to room temperature with moderate stirring.
[0094] These substances and compositions are evaluated in vitro according to the application methods described in example 2, for their capacity to block pigmentation induced by visible light, by a physical method in vitro, by measuring their absorbance A, at different wavelengths (noted "i") and by calculating the protection factor against blue light by applying the formulas: a) For i from 418 to 420 nm, we calculate the Blue Light Protection Factor 2 by applying the formula BLP = q 25847^-4 j 10; for a value of this coefficient (0.25847) between 0.12 and 0.39, the measured variations remain acceptable within the framework of the invention; or b) For i from 400 to 468 nm, the Blue Light Protection Factor is calculated by applying the formula BLP = q qj 168^^^1- ; for a value of this coefficient (0.01168) between 0.005 and 0.018, the measured variations remain acceptable within the framework of the invention; or c) For i at 420 nm, the Blue Light Protection Factor is calculated by applying the formula BLP = q 77663^1 - 10 ^420^ ' For a value of this coefficient (0.77663) between 0.39 and 1.16, the measured variations remain acceptable within the framework of the invention.
[0095] The results are as follows: [Tables 9] Applied composition None GHIJ BLP according to a 0 9% 41% 50% 35% BLP according to b 0 9% 41% 47% 36% BLP according to c 0 9% 41% 50% 35%
[0096] It can be seen that the results are consistent and similar to each other. The method developed therefore makes it possible to carry out screenings of compositions and substances in a much faster way than by the techniques usually used. As in example 1, the ecobiological compositions H, I and J are shown by this method to be significantly effective in blocking the effects of visible light on skin pigmentation. These tests demonstrate in particular the benefit of integrating the iron oxide ingredients used in these compositions H, I and J to produce formulations aimed at protecting against visible light, and in particular blue light.
[0097] Example 4: Evaluation of protection against visible light-induced pigmentation of cosmetic substances and compositions by an in vitro physical method
[0098] The following formulations are made. The name of the substances used is given according to their INCI name. The composition values are given in grams per 100 grams. K: Protection with BLP XX L: Protection with BLP XXI M: Protection with BLP XXII N: Protection with BLP XXIII
[0099] [Table 10] Oil phase: KLMN DIBUTYL ADIPATE 15 15 15 15 DIETHYLAMINO HYDROXYBENZOYL HEXYL BENZOATE 4 4 4 4 METHYLENE BIS-BENZOTRIAZOLYL TETRAMETHYLBUTYLPHENOL [NANO] 3.5 3.5 3.5 3.5 DIETHYLHEXYL BUTAMIDO TRIAZONE 3 3 3 3 BIS-ETHYLHEXYLOXYPHENOL ME-THOXYPHENYL TRIAZINE 2 2 2 2
[0100] [Table 11] Aqueous phase: KLMN AQUA / WATER / EAU qs 100 qs 100 qs 100 qs 100 qs 100 CORN STARCH MODIFIED 2 2 2 2 PENTYLENE GLYCOL 2 2 2 2 PROPANEDIOL 2 2 2 2 XANTHAN GUM 0.25 0.25 0.25 0.25 SODIUM LAUROYL GLUTAMATE 0.1 0.1 0.1 0.1 SODIUM HYDROXIDE 0.1 0.1 0.1 0.1
[0101] [Table 12] Powders and pigments: KLMN TITANIUM DIOXIDE [NANO] 7.6 7.6 7.6 7.6 MAGNESIUM OXIDE 3 0 0 0 MANGANESE OXIDE 3 0 0 0 MANGANESE DIOXIDE 3 0 0 0 CALCIUM OXIDE 3 0 0 0 CHROMIUM OXIDE 0 3 0 0 BARIUM / CALCIUM / SILICON / TITANI 0 3 0 0 UM OXIDE CALCIUM CERIUM OXIDE 0 3 0 0 CERIUM OXIDE 0 3 0 0 CLAY MINERAL OXIDE 0 0 3 0 ZINC CERIUM OXIDE 0 0 3 0 ZIRCONIUM DIOXIDE 0 0 3 0 CUPRIC OXIDE 0 0 3 0 CUPROUS OXIDE 0 0 0 3 TIN OXIDE 0 0 0 3 TUNGSTEN OXIDE 0 0 0 3 GERMANIUM DIOXIDE 0 0 0 3
[0102] The aqueous and oily phases are prepared independently and are heated to 60°C with moderate stirring (planetary or Raynerie type) until homogeneous preparations are obtained. The phases are then combined with very vigorous stirring at 60°C (Ultraturax type) for 15 minutes, then cooled to room temperature with moderate stirring.
[0103] These substances and compositions are evaluated in vitro according to the application methods described in example 2, for their capacity to block pigmentation induced by visible light, by a physical in vitro method, by measuring their absorbance Aj at different wavelengths (noted "i") and by calculating the protection factor against blue light by applying the following formula:
[0104] For i from 400 to 468 nm, the Blue Light Protection Factor is calculated by applying the formula BLP = q qj 1Q / >+ j ' For a value of this coefficient (0.01168) between 0.005 and 0.018, the measured variations remain acceptable within the framework of the invention.
[0105] The results are as follows: [Tables 13] Applied composition None KLMN BLP 0 62% 68% 75% 72%
[0106] We see that the results are high, all the formulas evaluated being considered as BLP 60+ and the M and N formulations can even be classified as BLP 70+. The method developed therefore makes it possible to carry out screenings of compositions and substances in a much faster way than by the techniques usually used. As in examples 1 to 3, the ecobiological compositions K, L, M and N prove by this method to be significantly effective in blocking the effects of visible light on skin pigmentation. These tests demonstrate in particular the interest of integrating the mineral ingredients used in these compositions, to produce formulations aimed at protecting from visible light and in particular from blue light, such as: Titanium Dioxide, Iron Oxide, Magnesium Oxide, Manganese Oxide, Manganese Dioxide, Calcium Oxide, Chromium Oxide, Calcium Cerium Oxide, Cerium Oxide, Clay Ore Oxide, Zinc Cerium Oxide, Barium / Calcium / Silicon / Titanium Oxide, Zirconium Dioxide, Cupric Oxide, Cuprous Oxide, Tin Oxide, Tungsten Oxide, or Germanium Dioxide.
Claims
Claims
1. Method for evaluating the protection rate of an eco-biological, cosmetic or dermatological composition containing a cosmetic active ingredient, against pigmentation induced by visible light, in particular by blue light, characterized in that it comprises: a) the formulation of said composition containing a cosmetic active ingredient in a test composition having a rheology compatible with spreading on a flat in vitro test surface; b) the application of this test composition on a first test plate, of composition adapted to receive irradiation with a UV-visible simulator and allow the reading of the absorbance, on a thickness adapted to the in vitro test; c) the application on a second in vitro test plate of the same composition as the first test plate called “Control Plate” for the measurement of the “background noise” of a suitable quantity of a control composition having a rheology compatible with spreading on a flat in vitro test surface, said composition not containing a cosmetic active ingredient absorbing visible light and comprising for example an alcohol, a polyglycol, in particular glycerol. d) drying the plates for 15 minutes in the dark and at room temperature; e) possible irradiation of the plates at 600W / m2 with a UV-visible simulator; f) reading the absorbance at wavelength i noted “Abi” of the plates between 400 and 700 nm after insertion into a UV-Visible spectrophotometer; g) reading the “background noise” absorbance noted Ci of the Control Plate described in c) between 400 and 700 nm h) For each wavelength denoted “i”, the net absorbance denoted Ai is the result of “Ai = Abi-Ci” i) The Blue Light Protection Factor, denoted BLP, is calculated by applying any of the following methods: I. For i from 418 to 420 nm, the Blue Light Protection Factor is calculated by applying the formula BLP = * y'=420 / i 1 C4+ H* ~ 1 ; with 0.12 < x < 0.39, advantageously x = ' ^=4181 / 2 / 0.25847; or II. For i from 400 to 468 nm, we calculate the Protection Factor of the Blue Light by applying the formula BLP = * y ~4W nr% \ ; with 0.005 < 3' < 0.018, advantageously = > 2 / 0.01168 ; or III. For i at 420 nm, the Blue Light Protection Factor is calculated by applying the formula BLP = _ lO^420^ ' with 0-39 < c < 1.16, advantageously z = 0.77663.
2. Method for adjusting the protection rate of an eco-biological, cosmetic or dermatological composition containing a cosmetic active ingredient, the value of which measured according to claim 1 is less than 50%, consisting of changing a cosmetic active ingredient, modifying its concentration or modifying the composition containing it until a protection rate of at least 50% is reached, measured according to claim 1.
3. Method for adjusting the protection rate of an eco-biological, cosmetic or dermatological composition containing a cosmetic active ingredient, the value of which measured according to claim 1 is less than 50%, consisting of changing a cosmetic active ingredient, modifying its concentration or modifying the composition containing it until a protection rate of 60%, advantageously at least 70%, measured according to claim 1 is reached.
4. Method for selecting a cosmetic or dermatological ecobiological composition containing a cosmetic active ingredient, comprising the following steps: - determining the protection rate of the composition containing the cosmetic active ingredient, according to the method which is the subject of claim 1, - selecting the composition containing the cosmetic active ingredient, having a BLP protection rate of at least 50%, in particular at least 60% and even better at least 70%, noted respectively BLP 50 or BLP 50+, BLP 60 or BLP 60+, BLP 70 or BLP 70+.
5. Method according to one of claims 1 to 4, characterized in that the cosmetic active ingredient is chosen from Titanium Dioxide, Iron Oxide, Magnesium Oxide, Manganese Oxide, Manganese Dioxide, Calcium Oxide, Chromium Oxide, Calcium Cerium Oxide, Cerium Oxide, Clay Ore Oxide, Zinc Cerium Oxide, Barium / Calcium / Silicon / Titanium Oxide, Zirconium Dioxide, Cupric Oxide, Cuprous Oxide, Tin Oxide, Tungsten Oxide, or Germanium Dioxide.