pigment

Abstract

A yellow to orange pigment for cosmetic applications is provided, which exhibits excellent color and stability characteristics, while being fully plant-based, edible and of natural origin.

Description

[0001] Pigment

[0002] The present invention relates to a yellow to orange pigment for cosmetic applications, in particular for make-up compositions.

[0003] Cosmetics are products used to enhance or change the appearance of the face, fragrance or the texture of the body. They are generally mixtures of chemical compounds derived from natural sources (such as coconut oil), or may be synthetic or artificial. Cosmetics that are applied to the face to enhance one's appearance are also known as make-up, which include items such as lipstick, mascara, eye shadow, foundation, blush, highlighter, bronzer and several other products.

[0004] In the United States, the Food and Drug Administration (FDA), which regulates cosmetics, defines cosmetics as "intended to be applied to the human body for cleansing, beautifying, promoting attractiveness, or altering the appearance without affecting the body's structure or functions". This broad definition includes any material intended for use as an ingredient of a cosmetic product.

[0005] Color cosmetics or make-up encompasses different categories of products for skin, eyes, cheeks and lips. It is a growing market as consumers increasingly seek to be always selfie-ready. Color cosmetics can enhance overall physical appearance, conceal flaws or define features, making one appear healthier and look more refreshed. Consumers have also expressed that color cosmetics have helped improve their mental well-being, by empowering them and boosting their selfconfidence.

[0006] The four main categories are: face make-up, such as foundation, blushers, illuminators, face bronzing lotions, creams and powders, loose and pressed powders, and mineral powders; eye make-up, such as eye shadows, eyeliners, eyebrow pencils, kohl and mascara, and mineral powders; lip make-up, such as lipstick, lip glosses, lip pencils, lip plumpers, pots and palettes; and nail make-up, such as nail varnishes and polishes, hardeners and strengtheners, base and top coat.

[0007] Lip color is currently the most active color cosmetics category, accounting for 32% of new launches with over 900 million lipsticks sold worldwide every year. Key performance attributes sought by consumers are color (93%), duration or long-lastingness (90%), texture (90%) and finish (89%).

[0008] Today, the yellow and orange pigments used in most color cosmetics on the market are either synthetic or mineral.

[0009] There is, however, a growing consumer demand for cleaner, healthier, more natural and more sustainable beauty products. 32% of consumers state that natural / organic make-up is their first choice, and 63% like it but not always buy it. In particular young consumers are looking for vegan alternatives.

[0010] But consumers are not willing to compromise on performance, even for a 100% natural lipstick. Less than 15% would accept reduced performance with regard to color, coverage and finish. In particular, long-lastingness is clearly an unmet consumer need.

[0011] It is therefore an objective of the present invention to provide plant-based pigments of natural-origin, which exhibits excellent color, coverage, long-lastingness and finish characteristics.

[0012] This problem has been solved by the pigment and cosmetic composition of the present invention.

[0013] In a first aspect, the present invention provides a pigment for use in cosmetic applications, comprising micronized Curcuma longa L. root extract and kaolinite clay.

[0014] The pigment of the invention is of 100% natural origin according ISO16128, cosmos approved, and China compliant. More importantly, it is easily dispersible in anhydrous cosmetic formulae, has a high intensity (chroma C*) and coverage (Cr*), as well as a good spreadability, and is stable to light and temperature.

[0015] Surprisingly, the pigment of the invention was found to perform even better than commercially available, non-natural alternatives in certain applications.

[0016] In a second aspect, the present invention provides a cosmetic composition comprising the pigment of the invention and a cosmetically acceptable excipient.

[0017] Turmeric, or curcuma, (Curcuma longa Linn) is a member of the Zingiberaceae family. It is cultivated in tropical and subtropical regions around the world and originates from India, Southeast Asia and Indonesia. Turmeric powder is used extensively as a coloring and flavoring agent in curries and mustards. It has traditionally been used for medical purposes for many centuries in countries such as India and China. Turmeric is one of the most popular medicinal herbs, with a wide range of pharmacological activities such as antioxidant, anti-protozoal, anti-venom activities, anti-microbial, anti-malarial, anti-inflammatory, anti-proliferative, anti-angiogenic, anti-tumor and anti-aging properties. It has also been used to treat ulcers, parasitic infections, various skin diseases, anti- immune diseases and curing the symptoms of colds and flus (Journal of Traditional and Complementary Medicine 7 (2017) 205-233). Throughout this disclosure, the terms “turmeric”, “curcuma”, “Curcuma longa L.” and “Curcuma longa Linn” are used interchangeably unless otherwise noted.

[0018] In cosmetics, the INCI name “CURCUMA LONGA (TURMERIC) ROOT EXTRACT” is typically used. Sometimes, it is also identified by CAS number 84775-52-0 and / or EC number 283-882-1.

[0019] During the extensive studies leading to the present invention, several botanical extracts (gardenia, turmeric, safflower) were tested, and turmeric was found to provide the best results.

[0020] Turmeric extracts are typically liposoluble, which makes them rather suitable for use in anhydrous cosmetic compositions.

[0021] Surprisingly, it was found that the addition of kaolinite clay allowed to increase the C* (intensity) of the pigment.

[0022] Furthermore, micronization was found to improve its spreadability.

[0023] Kaolinite clay (also called kaolin) is a clay mineral with the chemical composition AI2Si2O5(OH)4. It is a layered silicate mineral, with one tetrahedral sheet of silica (SiO4) linked through oxygen atoms to one octahedral sheet of alumina (AIO6). Kaolinite is a soft, earthy, usually white, mineral, produced by the chemical weathering of aluminium silicate minerals like feldspar.

[0024] Throughout this disclosure, the terms “kaolinite”, “kaolinite clay”, and “kaolin” are used interchangeably unless otherwise noted. It may also be identified by the CAS number 1332-58-7.

[0025] During the extensive studies leading to the present invention, several clays were evaluated. Surprisingly, it was found that kaolinite provided the best stability and highest intensity. This finding is contra-intuitive, as kaolinite has an inactive nature based on its structure. Furthermore, it was described in the prior art (e.g. Shue Li, Bin Mu, Xiaowen Wang, Aiqin Wang, “Recent researches on natural pigments stabilized by clay minerals: A review”, Dyes and Pigments, Volume 190, 2021 , 109322, ISSN 0143-7208) that kaolinite is not very suitable for stabilizing natural pigments.

[0026] As an alternative or in addition to kaolinite, montmorillonite may also be used in the pigment of the invention.

[0027] It has been found that by micronizing the Curcuma longa L root extract, and optionally also the kaolinite clay, a highly uniform pigment with good dispersibility and spreadability can be obtained. Curcuma longa L root extract typically comprises a number of components, which may slightly vary depending on origin, season and production method.

[0028] Among the extract’s components, curcuminoids, and in particular curcumin, are highly relevant for the yellow to orange color. Curcuminoids are linear, diarylheptanoid molecules that include curcumin, demethoxycurcumin, bisdemethoxycurcumin, and cyclocurcumin. It is therefore desirable that the Curcuma longa L. extract comprises a relatively high amount of curcuminoids, and in particular curcumin (which is typically the most prevalent component).

[0029] Therefore, in an embodiment, the Curcuma longa L. root extract comprises about 70 wt% to about 99.9 wt% of curcuminoids, more preferably about 90 wt% to about 99.5 wt% of curcuminoids, and still more preferably about 95 wt% to about 99 wt% of curcuminoids, based on the total weight of the Curcuma longa L. root extract. Preferably, the Curcuma longa L. root extract comprises at least about 90 wt%, more preferably at least about 95 wt% of curcuminoids, based on the total weight of the Curcuma longa L. root extract.

[0030] In an embodiment, the Curcuma longa L. root extract comprises about 50 wt% to about 95 wt% of curcumin, more preferably about 70 wt% to about 90 wt% of curcumin, and still more preferably about 80 wt% to about 85 wt% of curcumin, based on the total weight of the Curcuma longa L. root extract. For example, the Curcuma longa L. root extract may comprise about 82 wt% to about 84 wt% of curcumin, based on the total weight of the Curcuma longa L. root extract. Preferably, the Curcuma longa L. root extract comprises at least about 65 wt%, more preferably at least about 75 wt% of curcumin, based on the total weight of the Curcuma longa L. root extract.

[0031] Suitable methods for obtaining the Curcuma longa L. root extract are generally known in the art.

[0032] For example, the processes described in European Regulation No. 231 / 2012 may be followed. This regulation describes the preparation of food additives, and in particular E100 Curcumine. It also provides a list of solvents that may be used for the extraction, including ethyl acetate, acetone, dichloromethane, n-butanol, methanol, ethanol and propan-2-ol. Thus, Curcuma longa L. roots may be extracted with ethanol, for instance, to obtain a liquid extract.

[0033] A liquid extract may be subjected to concentration, spray drying, and / or other drying techniques known in the art to obtain a solid extract.

[0034] Preferably, a solid extract is used for the preparation of the pigment of the invention. The Curcuma longa L root extract may also comprise a number of other components, for example Ar-turmerone, p-turmerone, triglycerides and other fatty compounds, Intermedin B, p-sisterol glucoside, and Letestuianin.

[0035] The Curcuma longa L root extract used in the pigment of the invention is micronized. It has been found that micronization has a positive impact on chroma and coverage.

[0036] The most commonly used metrics when describing particle size distributions are D-Values: D10, D50 and D90, which are the intercepts for 10%, 50% and 90%, respectively, of the cumulative distribution. The D50 is the diameter of the particle that 50% of a sample's mass is smaller than and 50% of a sample's mass is larger than. In other words: D represents the diameter of powder particles, and D50 means a cumulative 50% point of diameter (or 50% pass particle size); D10 means a cumulative 10% point of diameter. D50 is also called average particle size, median diameter, mass-median-diameter (MMD) or log-normal distribution mass median diameter.

[0037] D50 is also divided into Dv50, Dw50 and Dn50; Dv50 means volume D50, whereas Dw50 is mass D50 and Dn50 is number D50. Dv50 is also known as volume median or volume average particle size, it physically represents that each volume of particles greater or smaller than such value takes account of 50% of the total particles volume. Dn50 is known as number median, it physically represents that each number of particles greater or smaller than such value takes account of 50% of the total particles number.

[0038] In an embodiment, the micronized Curcuma longa L. root extract has a volume median particle size (Dv50) of from about 1.0 pm to about 7.5 pm, more preferably of from about 1 .5 pm to about 6.0 pm, and most preferably from about 2.0 pm to about 5.0 pm.

[0039] In an embodiment, the micronized Curcuma longa L. root extract has a volume particle size 90% percentile (Dv90) of from about 3.0 pm to about 20.0 pm, more preferably of from about 4.0 pm to about 17.0 pm, and most preferably from about 5.0 pm to about 15.0 pm.

[0040] Depending on the intended use or application, the ratio between the micronized Curcuma longa L. root extract and the kaolinite clay may be selected by the skilled person. For most cosmetic applications, a weight ratio in which the two components are used in amounts of similar magnitude is suitable.

[0041] In an embodiment, the weight ratio of micronized Curcuma longa L. root extract to kaolinite clay is from about 1 :2 to about 2:1 , more preferably from about 1 :1.5 to about 1 :1. These ratios have been found to be particularly suitable for color cosmetic applications, such as lipsticks, eye shadows or compacted powders, for example.

[0042] For instance, the concentration of micronized Curcuma longa L root extract in the pigment can be from about 30 wt% to about 70 wt%, more preferably from about 40 wt% to about 60 wt%, and most preferably from about 45 wt% to about 55 wt%; e.g. about 50 wt% of micronized Curcuma longa L. root extract.

[0043] For instance, the concentration of the kaolinite clay in the pigment can be from about 30% to about 70%, more preferably from about 40% to about 60%, and most preferably from about 45% to about 55%; e.g. about 50% of kaolinite clay.

[0044] Depending on the curcuminoid content of the Curcuma longa L. root extract and on the amount of extract used in the pigment of the invention, the curcuminoid content of the pigment will vary.

[0045] In an embodiment, the pigment comprises about 25 wt% to about 75 wt% of curcuminoids, more preferably about 35 wt% to about 65 wt% of curcuminoids, and still more preferably about 45 wt% to about 55 wt% of curcuminoids, based on the total weight of the pigment. For example, the curcuminoid content of the pigment may be about 47 wt% or slightly higher.

[0046] Analogously, depending on the curcumin content of the Curcuma longa L. root extract and on the amount of extract used in the pigment of the invention, the curcumin content of the pigment will vary.

[0047] In an embodiment, the pigment comprises about 20 wt% to about 55 wt% of curcumin, more preferably about 30 wt% to about 50 wt% of curcumin, and still more preferably about 40 wt% to about 45 wt% of curcumin, based on the total weight of the pigment. For example, the curcuminoid content of the pigment may be about 35 wt% or higher, e.g. about 41 wt%.

[0048] The pigment of the present invention may further comprise a suitable carrier.

[0049] Therefore, in an embodiment of the present invention, the pigment of the present invention further comprises a polysaccharide (preferably maltodextrin), gum arabic, starch, cellulose, silica, calcium stearate, calcium carbonate, tricalcium phosphate, glucose syrup, or any other suitable carriers or mixtures thereof.

[0050] The pigment of the invention typically has a yellow to orange color, with varying shade depending on the concentrations of the components used. For example, the pigment may provide a yellow color similar to Pantone 7409 U (CMYK: 0; 31 ; 68; 1 / / sRGB: 252; 173; 80 / / Hex: #FCAD50 / / Light Reflectance Value (LRV) = approx. 52).

[0051] The shade will also somewhat vary depending on the amount of pigment used in a cosmetic formulation. For example, at a concentration of about 0.17 wt% of the pigment in a make-up formulation, a yellow color is observed, whereas a concentration of about 0.70 wt% will provide a more orange shade.

[0052] In order to adjust the shade to the desired color, it is also possible to include a color-adjusting substance in the pigment of the invention, for example titanium dioxide (TiO2), zinc oxide, microcrystalline cellulose, calcium sulfate, calcium carbonate or guanine for obtaining a lighter shade or other pigments such as Unipure Yellow LC188 (INCI: CI77492, iron oxides), Unipure Yellow LC125 (Cl 19140, Yellow 5 Lake), Unipure Orange LC226 (Cl 15985, Yellow 6 Lake), or Carbon Black (Cl 77268:1 ; charcoal) for obtaining darker shades.

[0053] The positive effects of micronization have been discussed above.

[0054] In an embodiment of the present invention, not only the Curcuma longa L. root extract is micronized, but also the kaolinite clay and, if present, any other solid components. Preferably, most of the solid components are micronized. More preferably, at least all solid components of the pigment are micronized.

[0055] In an embodiment of the present invention, the entire pigment is micronized. The micronization can be done either on the separate components, on several partial mixtures, or on the full composition. It is also possible to perform several micronization steps.

[0056] In a second aspect, the present invention provides a cosmetic composition comprising the pigment of the invention and a cosmetically acceptable excipient.

[0057] Preferably, the cosmetic composition comprises the pigment of one or more of the specific embodiments outlined above.

[0058] Any excipients commonly used in the preparation of cosmetic preparations for use on the human skin may be employed in the present invention. Suitable excipients include, but are not limited to ingredients that can influence organoleptic properties, dispersability, appearance, and spreadability of the pigment of the present invention. More specifically, they include liquids, such as water, oils or surfactants, including those of petroleum, animal, plant or synthetic origin, such as and not restricted to, peanut oil, soybean oil, mineral oil, sesame oil, castor oil, polysorbates, sorbitan esters, ether sulfates, sulfates, betaines, glycosides, maltosides, fatty alcohols, nonoxynols, poloxamers, polyoxyethylenes, polyethylene glycols, dextrose, glycerol, digitonin, squalene, hemisqualene, and the like, as well as mixtures thereof.

[0059] The cosmetic composition may take any physical form and may be produced in any solid, liquid, or semi-solid form useful for application.

[0060] In an embodiment, the cosmetically acceptable excipient comprises castor oil. More preferably, the cosmetically acceptable excipient at least essentially consists of castor oil. Castor oil is of natural origin and has been found to provide a good dispersion of the pigment of the invention.

[0061] In an embodiment, the cosmetically acceptable excipient comprises squalene and / or hemisqualene. More preferably, the cosmetically acceptable excipient at least essentially consists of squalene and / or hemisqualene. Squalene and / or hemisqualene have been found to provide a good dispersion of the pigment of the invention.

[0062] In an embodiment, the cosmetically acceptable excipient comprises a mixture of castor oil with squalene and / or hemisqualene.

[0063] The cosmetic composition of the present invention is typically a color cosmetic or make-up composition. Possible product formats have been mentioned in the introductory section above.

[0064] In an embodiment, the cosmetic composition of the present invention is selected from the group consisting of a lipstick, a lip balm, a lip oil, a lip gloss, a lip scrub, a make-up emulsion, a make-up powder, a make-up oily gel, an eye shadow, a compacted powder, a nail polish, a mascara, a foundation, and a soap.

[0065] In a preferred embodiment, the cosmetic composition of the invention is a lipstick composition, an eye shadow composition or a compacted powder composition.

[0066] Surprisingly, the pigment of the invention also exhibited a pro-pigmenting activity. This is particularly unexpected in view of the fact that the state of the art describes a whitening activity for turmeric extracts I curcuminoids (e.g. “Molecular interaction of curcumin, demethoxycurcumin, bisdemethoxycurcumin, and turmerone of Curcuma longa with tyrosinase and tyrosinase-related protein-1”, Firmansyah, D.; Sumiwi, S. A.; Saptarini, N. M.; Levita, J.Rasayan Journal of Chemistry (2021), 14(4), 2298-230. “The melanin inhibitory effect of plants and phytochemicals: A systematic review”, Feng, Danni; Fang, Zhongxiang; Zhang, Pangzhen, Phytomedicine (2022), 107, 154449. “Curcumin inhibits melanogenesis in human melanocytes” Tu, C., Lin, M., Lu, S., Qi, X., Zhang, R., Zhang, Y., 2012. Phytother. Res. 26 (2), 174-179). By contrast, the studies conducted by the present team revealed a stimulation of melanogenesis (see Example 7 below).

[0067] The pigment of the invention was also found to provide antioxidant and anti-inflammatory activity.

[0068] In view of this biological activity, the pigment of the invention is also highly beneficial for skin care applications.

[0069] Therefore, in an embodiment, the cosmetic composition of the invention is a skin care composition.

[0070] The present invention is further illustrated by means of the following non-limiting examples:

[0071] Example 1 : Preparation of Pigment

[0072] Curcuma longa L. root extract is commercially available from several suppliers, for example from Arjuna Natural Extracts Ltd. in India.

[0073] Kaolinite clay is commercially available from several suppliers, for example from Color Clay Natural S.L. in Spain.

[0074] In order to prepare the pigment of the invention, 200 kg of a solid Curcuma longa L. root extract were dispersed in 600 kg of tap water and 200 kg of kaolinite clay were added. The mixture was stirred at 50 °C for 15-30 min until homogeneisation, e.g. using Koruma Romaco DH160 equipment.

[0075] The thus obtained mixture was spray dried with a spray dry apparatus (Anhydro spx flow) to obtain 360 kg of powder. Micronization (e.g. by air jet micronization; e.g. using Hosokawa Alpine 200) of the powder afforded 342 kg of micronized powder.

[0076] The micronized powder was sterilized by saturated steam water (Steripure).

[0077] The thus obtained pigment had a particle size distribution of Dv10 = 1.25 pm, Dv50 = 4.28 pm, and Dv90 = 9.61 pm. Example 2: Characteristics of Pigment

[0078] Six different batches of pigments according to Example 1 were assessed and found to exhibit the following characteristics:

[0079] The curcumin and curcuminoids contents were measured by HPLC with UV detection. A suitable method is described: Journal of Pharmacognosy and Phytochemistry, 2018, 7(5), p. 1913-1918, “Standardizaton and quantification of curcumin from Curcuma longa extract using UV visible spectroscopy and HPLC”, by Prasad V Kadam et al.

[0080] The colorimetric properties were measured through L,a,b measurements (Spectrocolorimeter Konica-Minolta 3600d (D65, L*, a*, b*, h, C*, Y)). L,a,b colorimeters are widely used to evaluate color variations of products. Any color shade can be specified by three coordinates in the L*,a*,b* three- dimensional system:

[0081] - the L* axis runs from 0 (black) to 100 (white)

[0082] - the a* axis (green / red direction)

[0083] - the b* axis (blue / yellow direction).

[0084] Positive a* is red, and the higher the a* value, the more intense the red. Analogously, negative a* is green, positive b* is yellow, and negative b* is blue.

[0085] L* is the clarity value, representing darkness to lightness, with values ranging from 0 to 100. The 50% light level is considered "normal" and is often used to display colors.

[0086] Y refers to the relative Luminance. This is a photometric measure of the luminous intensity per unit area of light travelling in a given direction. It is used to determine the opacity or coverage.

[0087] Opacity is a measure of covering power, 100% opacity means full coverage.

[0088] Opacity / coverage (CR) is calculated as follows: CR (%) = ((Y black*100) / Y white) Chroma (C*) is the amount of saturation of a color. Colors of high chroma are said to be clear, bright or brilliant. Dull (pastel) colors have a low chroma. Lower saturation means that the color has more grey and appears faded and less intense.

[0089] Hue (h) is the color tone or color name of a color. It is the property of light which identifies color within the spectrum. Hue ranges over colors with familiar names like red, orange, yellow, green, blue, indigo, and violet. For convenience, hue is often visualized to be on a color wheel or circle. In Web colors, hue is measured in 360 degrees of a color circle. Red is at 0°, green is at 120°, and blue is 240°. At 360°, the measure of hue goes back to 0°. of Plant Extracts

[0090] Three different yellow plant extracts were tested:

[0091] - T urmeric extract Gardenia extract Safflower extract

[0092] The turmeric extract is described above in Example 1 .

[0093] Yellow Gardenia extracts are commercially available. In the present testing, “Gardenia yellow powder” from Yunnan Rainbow Biotech. Corp., Ltd. was used. According to the supplier, this material has the following composition: maltodextrin (±5%) and gardenia jasminoides fruit extract (±95%).

[0094] Safflower Gardenia extracts are also commercially available. In the present testing, “Safflower yellow powder” from Yunnan Rainbow Biotech. Corp., Ltd. was used. According to the supplier, this material has the following composition: 67±5% maltodextrin and 33±5% carthamus tinctorius flower (safflower) extract.

[0095] From each of these extracts, test pigments were prepared by suspending the respective extract in water, adding the respective clay under stirring and drying the resulting mixture by spray drying. The type of clay and quantities of extracts and clays used are shown in the table below.

[0096] The colorimetric properties were measured through L,a,b measurements (Spectrocolorimeter Konica-Minolta 3600d (D65, L*, a*, b*, h, C*)).

[0097] As can be seen from the above table, the pigment based on turmeric extract and kaolin, according to the invention, exhibited the highest b* value of the samples tested, meaning that it provided the strongest yellow color. In addition, this pigment also had the highest C* value. This confirms that the pigment of the invention provides the best results.

[0098] Example 4: Effect of Micronization

[0099] In order to assess the effect of micronization, samples of turmeric extract and kaolin (both commercially available) were micronized and compared to the respective non-micronized materials and to the pigment of the present invention (turmeric extract / kaolin 50:50, micronized). The colorimetric properties were measured through L,a,b measurements (Spectrocolorimeter Konica-Minolta 3600d (D65, L*, a*, b*, h, C*)). The granulometry of the turmeric-containing samples was determined using a particle size analyser Mastersizer 3000+ Ultra from Malvern Panalytical.

[0100] As can be seen from the above table, micronization allowed to modify the colorimetric parameters and to increase the Chroma C* and the L* of the turmeric extract, but has hardly any impact on the kaolin. In particular, micronization leads to a strong increase of the b* value, which indicates yellowness. Furthermore, the particle size of the micronized samples 2 and 6 is clearly more uniform than that of the non-micronized samples 1 and 5.

[0101] Photographs of the powder samples 1 , 2, 5, and 6 are shown in Figure 1 . As can be seen from these photographs, Sample 6 looks really yellow, while the other three samples tend to look more orange. This difference is clearly visible to the eye.

[0102] Example 5: Comparison of Clays

[0103] In order to assess the impact of the clay used, the following two commercially available clays were tested:

[0104] - Montmorillonite: CosWHITE™ (supplied by Argile du Velay)

[0105] - Kaolin: CosKAO™ (supplied by Argile du Velay)

[0106] Pure turmeric extract, kaolin and montmorillonite, respectively, were subjected to micronization to obtain comparative samples.

[0107] For the mixtures, 500 g of curcuma extracts were dispersed in 2 kg of tap water, and 500 g of clay was added under stirring. The mixture was then spray dried and the resulting powder micronized to obtain the test samples.

[0108] The colorimetric properties were measured through L,a,b measurements (Spectrocolorimeter Konica-Minolta 3600d (D65, L*, a*, b*, h, C*)).

[0109] As can be seen from the above table, the addition of Montmorillonite to the turmeric extract led to a decrease in Lightness, Chroma and hue, as well as in the b* value (more yellow), and an increase in the a* value (more red). As can be seen from the above table, the addition of Kaolin to the turmeric extract had no impact on the Lightness, while causing a slight increase in hue and a slight decrease in Chroma, as well as a decrease in a* (more green) and b* (more yellow).

[0110] In addition, a stability testing revealed that the combination with Kaolin is much more stable than that with Montmorillonite, in essentially all tested conditions:

[0111] Example 6: Performance of Lipstick Compositions

[0112] In order to determine the coloring properties and performance in formulation, the pigment of the invention was formulated in a lipstick base at three different concentrations (Samples 1 , 2, and 3, with 10 wt%, 0.17 wt% and 0.7 wt% of pigment, respectively). For comparison, pure turmeric extract was also formulated at a concentration of 10 wt% in the same lipstick base (Sample 4).

[0113] Phase A was prepared by blending butyrospermum parkii butter, cera alba, caprylic / capric triglycerides, linoleic acid / propanediol copolymer, jojoba esters and helianthus annuus seed wax and acacia decurrens flower wax and polyglycerin-3 at a temperature of 80 °C until homogeneous. To obtain phase B, a mixture of the respective pigment powder and the castor oil was homogenized in a turrax blender for 2 min at room temperature.

[0114] The two phases were combined at 75 °C and blended in the turrax blender for 2 min.

[0115] The obtained lipstick composition was cooled down to room temperature for 2 hours under magnetic agitation.

[0116] Finally, 2 g of the thus optained lipstick compositions were crushed between glass slabs and applied to a contrast card using a film applicator (film thickness: 50 pm).

[0117] In addition, two comparative examples with commercially available pigments were prepared, which contained 10 wt% of Unipure Yellow LC 125 (by Sensient), a synthetic pigment, in the same lipstick base (Sample 5), and 10 wt% of Natpure Xfine Turmeric TU114 (by Sensient), a natural pigment based on curcuma longa extract, acacia Senegal gum and maltodextrin, in the same lipstick base (Sample 6).

[0118] L*,a*,b* measurements were performed on a Spectrocolorimeter Konica-Minolta 3600d (D65, L*, a*, b*, h , C*) and DeltaE(2000) was measured to see the color and opacity differences between the different pigments in lipstick base.

[0119] The results are shown in the following table:

[0120] #Turmeric extract / Kaolin 50:50, micronized

[0121] The pigment was evaluated at several concentrations: 0.17 wt%, 0.7 wt% and 10 wt%. At each of these levels, it showed a really high C*. Surprisingly, the impact on the chroma was not proportionate to the concentration.

[0122] Sample 4, without kaolin, exhibited a poor spreadability. Furthermore, as can be seen from a comparison with sample 1 , which was used at the same concentration, the pigment with a combination of turmeric extract and kaolin had a higher chroma C* and a higher b* value (i.e. was slightly more yellowish) than the one with turmeric extract alone.

[0123] As can be seen from a comparison of samples 1 and 5, both the natural pigment of the invention and the commercially available synthetic pigment exhibited a chroma C* of > 90. The Opacity, however, was higher for the pigment of the invention (44.07) than for the synthetic one (only 11.05).

[0124] As can be seen from a comparison of samples 1 and 6, both pigments exhibited a chroma C* of > 90. But again, the Opacity was higher for the pigment of the invention (44.07) than for the commercially available one (38.84).

[0125] The lipstick composition according to Sample 1 was further submitted to a stability study under different conditions. The results are shown in the following table:

[0126] As can be seen from the above, the color was highly stable under all conditions, with a dE2000 of less than 1.

[0127] For comparison, the same tests were conducted with Unipure Yellow LC 125. The results showed that the color of Unipure Yellow LC 125 is quite stable, but shows more variation (dE2000) than the yellow pigment of the invention: Example 7: Evaluation of Melanogenesis / Whitening Activity

[0128] The aim of this study was to evaluate the ability of the pigment of the invention to inhibit or to stimulate the synthesis of melanin. The model used for this evaluation was a co-culture of Normal Human Epidermal Keratinocytes (NHEKs) and Normal Human Melanocytes (NHMs).

[0129] Cell culture and treatment

[0130] The cell culture was realized with primary cells isolated from biopsies. Normal Human Keratinocytes (NHKs) were seeded at 100’000 cells per well in 6-wells plates pre-coated with collagen I. After 24 h of incubation in humid atmosphere at 37 °C in presence of CO2, Normal Human melanocytes (NHMs) were seeded at 80’000 cells per well in the same 6-wells plates for co-culture development. The cells were then incubated for 48 h in complete medium (Dermalife medium supplemented with Life factors K).

[0131] After 48 h of culture, the cells were stimulated for 5 d with the following conditions:

[0132] The test substances were pre-diluted in DMSO at 10 wt% and then diluted in a basal medium without supplements (Dermalife medium supplemented with 1 % w / v antibiotics). Every two days, the treatments were renewed.

[0133] The addition of L-tyrosine at 1 mM and a-MSH at 1 nM allowed the authors to evaluate the whitening activity of the Yellow Pigment.

[0134] Melanin extraction and dosage

[0135] After 5 days of treatment, cells were rinsed off with PBS. Then, to each well, 200 pl of a solution of NaOH 0.5 N was added. The cell lysates were collected in 1.5 ml microtubes with secure caps.

[0136] In parallel, a standard range of eight concentrations of melanin was prepared (0 to 100 pg / ml).

[0137] Microtubes of samples and standard range were heated for 1 h at 80 °C in a dry bath. After the heating step, 100 pl of each sample was transferred to a 96-wells plate.

[0138] Optical density was measured at 405 nm with a microplate reader (Spark®, TECAN).

[0139] Statistical analysis

[0140] A Shapiro- Wilk normality test was performed to evaluate whether the data follow the Gaussian Law. The results did not follow the Gaussian Law.

[0141] As a consequence, a non-parametric statistical analysis was performed by Kruskal-Wallis ANOVA followed by Mann Whitney U test. Results were considered significant with p<0.05 with *, p<0.01 with ** and p<0.001 with ***.

[0142] Results

[0143] The presented results are expressed in % of the untreated condition and are shown in the following table:

[0144] The melanogenesis control induced a significant increase of melanin synthesis by +22% (p<0.05). These results validated the experiments.

[0145] In the same conditions, the yellow pigment of the invention significantly induced the melanin synthesis by +19%*.

[0146] These results show that the pigment of the invention exhibits a pro-pigmenting activity under these experimental conditions.

[0147] Example 8: Evaluation of Anti-inflammatory Activity

[0148] The aim of this study was to evaluate the anti-inflammatory property of the pigment of the invention in keratinocytes. A pro-inflammatory stress was induced by a chemical agent (Phorbol Myristate Acetate). Then, the release of four cytokines was evaluated by multiplex assay: two of them are pro- inflammatory and two are anti-inflammatory. Cell culture and treatment

[0149] The cell culture was done on primary cells isolated from fresh biopsies. Normal Human Epidermal Keratinocytes (NHEKs) were seeded in a type I collagen pre-coated 24 wells-plate at 30’000 cells per well in triplicate. The cells were incubated for 24 h in complete medium (Dermalife medium supplemented with Life factors, Cell Systems) and 1 % of antibiotics (Sigma-Aldrich) at 37 °C with 5% CO2.

[0150] At the end of the incubation, the cells were rinsed twice with PBS (Gibco) and pre-incubated with the test substances for 24 h in Dermalife complete medium without hydrocortisone and 1 % of antibiotics at 37 °C with 5% CO2.

[0151] The cells were treated in complete medium with the following conditions:

[0152] The test substances were pre-diluted in DMSO at 10 wt%, then in at the desired concentration in the culture medium. The effects of the test substances were compared with castor oil as the initial solution of the Yellow Pigment was at 0.1 wt% in pure castor oil.

[0153] After 24 h of pre-incubation, the cells were stressed with PMA (Phorbol 12-myristate 13-acetate, Sigma) at 1 ng / ml and incubated for 24 h at 37 °C with 5% CO2.

[0154] Skin cells untreated and cultivated with medium were used as a negative control.

[0155] At the end of the culture, the cell media were collected and centrifuged at 2000 g for 10 min at 4 °C to eliminate dead cells. The media were stored at -20 °C.

[0156] An MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay was performed to evaluate treatments toxicity and for the normalisation of cytokines quantification.

[0157] MTT assay

[0158] MTT solution (Sigma) diluted at 1 mg / ml in basal medium was added to each well and incubated for 3 h at 37 °C, 5% CO2. Then, the medium was removed and 300 pL of dimethyl sulfoxide (DMSO, Sigma) was added to each well to dissolve the formazan crystals. Homogenization was done under orbital agitation for few minutes. The optical density was measured at a wavelength of 560 nm with microplate reader (Spark®, TECAN).

[0159] Cytokines quantification

[0160] TNF-a, IL-6, IL-10 and IL-1 Ra quantification were realized with a 4-plex assay (R&D Systems).

[0161] Briefly, the samples and the standard range were incubated for 2 h in 96-wells plate with specific beads with antibodies against TNF-a, IL-6, IL-10 and IL-1 Ra. After three washes with wash buffer using the magnetic device provided by the supplier, a Biotin-antibody cocktail was added to the wells for an incubation during 1 h under orbital agitation. Following three washes, a solution of Streptavidin- PE was added to the wells for 30 min. Finally, three more washes were conducted and the microparticles were resuspended in wash buffer. The read was then carried out by the Magpix® system (Luminex, Texas, USA).

[0162] The quantification was normalized with the optical density measured via the MTT assay.

[0163] An inflammatory balance was calculated by comparing the modulation of anti-inflammatory and pro- inflammatory cytokines.

[0164] Statistical analysis

[0165] A Shapiro- Wilk normality test was performed to evaluate whether the data follow the Gaussian Law.

[0166] The results did not follow the Gaussian Law.

[0167] As a consequence, a non-parametric statistical analysis was performed by Kruskal- Wall is ANOVA followed by Mann Whitney U test. Results were considered significant with p<0.05 with *, p<0.01 with ** and p<0.001 with ***.

[0168] Results

[0169] The presented results are expressed in % PMA stress and are summarized in the following table: The multiplex quantification demonstrated that, after 24 h of PMA stress, an inflammation state was triggered. The pre-treatment with the positive reference (dexamethasone) decreased the cytokines ratio by -63%*. These results confirmed the responsiveness of the model.

[0170] In the same conditions, the Yellow Pigment significantly decreased the cytokines ratio by up to 12%#versus castor oil.

[0171] These results confirm that the Yellow Pigment at 0.005% has an anti-inflammatory activity under these experimental conditions and can be used as a soothing ingredient.

[0172] Example 9: Evaluation of Spreadability in Cosmetic Formulation

[0173] Powder samples 1 , 2, 5, and 6 of example 4 were incorporated into a lipstick formulation as described in example 6 at a concentration of 10%.

[0174] The colorimetric properties of the resulting lipstick compositions were measured using a Spectrocolorimeter Konica-Minolta 3600d (h, C*), and the coverage (Cr).

[0175] As can be seen from the above, the coverage of the formulations increased drastically with micronization. And also the chroma increased.

[0176] Figure 2 shows photographs of the above formulations spread out on contrast cards.

[0177] As can be seen from these photographs, the spreadability of the formulations containing micronized pigments (2* and 6*) was much better than that of the other two formulations (1* and 5*).

[0178] Thus, overall, the pigments of the present invention exhibit a significantly better coverage and also provide a very yellow color.

Claims

1. Claims1. Pigment for use in cosmetic applications, comprising micronized Curcuma longa L root extract and kaolinite clay.

2. Pigment according to claim 1 , wherein the Curcuma longa L. root extract comprises about 70 wt% to about 99.9 wt% of curcuminoids, more preferably about 90 wt% to about 99.5 wt% of curcuminoids, and still more preferably about 95 wt% to about 99 wt% of curcuminoids, based on the total weight of the Curcuma longa L. root extract.

3. Pigment according to claim 1 or 2, wherein the Curcuma longa L. root extract comprises about 50 wt% to about 95 wt% of curcumin, more preferably about 70 wt% to about 90 wt% of curcumin, and still more preferably about 80 wt% to about 85 wt% of curcumin, based on the total weight of the Curcuma longa L. root extract.

4. Pigment according to any one of claims 1 to 3, wherein the micronized Curcuma longa L. root extract has a volume median particle size (Dv50) of from about 1 .0 pm to about 7.5 pm, more preferably of from about 1.5 pm to about 6.0 pm, and most preferably from about 2.0 pm to about 5.0 pm.

5. Pigment according to any one of claims 1 to 4, wherein the micronized Curcuma longa L. root extract has a volume particle size 90% percentile (Dv90) of from about 3.0 pm to about 20.0 pm, more preferably of from about 4.0 pm to about 17.0 pm, and most preferably from about 5.0 pm to about 15.0 pm.

6. Pigment according to any one of claims 1 to 5, wherein the weight ratio of micronized Curcuma longa L. root extract to kaolinite clay is from about 1 :2 to about 2:1 , more preferably from about 1 : 1.5 to about 1 :1.

7. Pigment according to any one of claims 1 to 6, comprising about 25 wt% to about 75 wt% of curcuminoids, more preferably about 35 wt% to about 65 wt% of curcuminoids, and still more preferably about 45 wt% to about 55 wt% of curcuminoids, based on the total weight of the pigment.

8. Pigment according to any one of claims 1 to 7, comprising about 20 wt% to about 55 wt% of curcumin, more preferably about 30 wt% to about 50 wt% of curcumin, and still morepreferably about 40 wt% to about 45 wt% of curcumin, based on the total weight of the pigment.

9. Pigment according to any one of claims 1 to 8, wherein the pigment has a yellow to orange color.

10. Pigment according to any one of claims 1 to 9, wherein at least all solid components of the pigment are micronized.

11. Cosmetic composition comprising the pigment according to any one of claims 1 to 10 and a cosmetically acceptable excipient, in particular a cosmetically acceptable excipient comprising castor oil.

12. Cosmetic composition according to claim 11 , which is a make-up composition, and in particular a lipstick composition, an eye shadow composition or a compacted powder composition.

13. Cosmetic composition according to claim 11 , which is a skin care composition.

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