pigment

Abstract

A blue 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 blue 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 blue 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] Blue color is not very common in nature, and the main available botanical or algae extracts are water- soluble, meaning that they are not compatible with anhydrous-oily cosmetic formulations.

[0012] 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.

[0013] This problem has been solved by the pigment and cosmetic composition of the present invention.

[0014] In a first aspect, the present invention provides a pigment for use in cosmetic applications, comprising micronized Spirulina platensis G. extract and kaolinite clay.

[0015] 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.

[0016] Surprisingly, the pigment of the invention was found to perform even better than commercially available, non-natural alternatives in certain applications.

[0017] In a second aspect, the present invention provides a cosmetic composition comprising the pigment of the invention and a cosmetically acceptable excipient.

[0018] Spirulina platensis G. (Microcoieaceae), also called Arthrospira platensis or Arthrospira maxima, is a blue-green, filamentous cyanobacterium (blue-green algae). These photosynthetic organisms were first considered to be algae, a very large and diverse group of eukaryotic organisms, until 1962, when they were reclassified as prokaryotes and named cyanobacteria.

[0019] Throughout this disclosure, the terms “spirulina”, “Spirulina platensis G ”, “Spirulina platensis Gomont”, “Spirulina platensis”, “Arthrospira platensis”, and “Arthrospira maxima” are used interchangeably unless otherwise noted. The filament of Spirulina platensis G. has an average length of about 250 m, is called trichrome, and takes a helical shape in a liquid medium.

[0020] Spirulina platensis G. grows naturally in fresh, alkaline, hot and mineralized waters. It has been found in saline lakes in tropical or semi-tropical regions, but more generally in all regions on the equator and a little north of the equator.

[0021] Spirulina is widely known as a food supplement, but there are other possible uses for this cyanobacterium.

[0022] Traditionally, Spirulina platensis G. was mostly used in food and health products, especially in underdeveloped countries. It was most often consumed in the form of patties, but was also used to treat skin problems. Known biological properties include wound healing, antimicrobial, antioxidative, anti-inflammatory, antimelanogenic, and anticancer properties.

[0023] In cosmetics, the INCI name “Spirulina platensis extract” is typically used. Sometimes, it is also identified by CAS number 223751-80-2.

[0024] Its pigmentary system is mainly made up of chlorophyll A (1%), carotenoids (0.5%) and C- phycocyanin (14-20%). C-phycocyanin, a water-soluble molecule that emits at a wavelength of 635 nm, is responsible for the blue color.

[0025] During the extensive studies leading to the present invention, several botanical extracts (persicaria tinctoria (indigo), daucus carota L., ipomoea batatas L. (purple sweet potato), brassica oleracea L. var rubra (red cabbage), Genipa americana L.) were tested, and spirulina was found to provide the best results.

[0026] Surprisingly, it was found that the addition of kaolinite clay allowed to increase the C* (intensity) of the pigment.

[0027] Furthermore, micronization was found to improve its spreadability.

[0028] 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. 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.

[0029] 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.

[0030] As an alternative or in addition to kaolinite, illite and / or montmorillonite may also be used in the pigment of the invention.

[0031] It has been found that by micronizing the Spirulina platensis G. extract, and optionally also the kaolinite clay, a highly uniform pigment with good dispersibility and spreadability can be obtained.

[0032] Spirulina platensis G. extract typically comprises a number of components, which may slightly vary depending on origin, season and production method.

[0033] Among the extract’s components, phycocyanins, and in particular C-phycocyanin, are highly relevant for the blue color. Phycocyanins are pigment-protein complexes from the light-harvesting phycobiliprotein family. The phycobiliproteins are made of two subunits (alpha and beta) having a protein backbone to which 1-2 linear tetrapyrrole chromophores are covalently bound.

[0034] C-phycocyanin is often found in cyanobacteria which thrive around hot springs, as it can be stable up to around 70 °C, with identical spectroscopic (light absorbing) behaviors at 20 °C and 70 °C. Its molecular weight is around 30’000 Da. It typically forms a heterohexamer ((a[3)6).

[0035] It is therefore desirable that the Spirulina platensis G. extract comprises a relatively high amount of phycocyanins, and in particular C-phycocyanin.

[0036] Therefore, in an embodiment, the Spirulina platensis G. extract comprises from about 45 wt% to about 75 wt% of phycocyanins, more preferably from about 50 wt% to about 70 wt% of phycocyanins, and still more preferably about 60 wt% of phycocyanins, based on the total weight of the Spirulina platensis G. extract. The phycocyaning content is typically determined on a dry basis. For example, the Spirulina platensis G. extract may comprise about 59 wt% of phycocyanins. Suitable methods for obtaining the Spirulina platensis G. extract are generally known in the art (see e.g.: Food Research International 143 (2021), Phycocyanin from Spirulina: A review of extraction methods and stability).

[0037] A liquid extract may be subjected to concentration, spray drying, and / or other drying techniques known in the art to obtain a solid extract.

[0038] Preferably, a solid extract is used for the preparation of the pigment of the invention.

[0039] The Spirulina platensis G. extract may also comprise a number of other components, for example fatty acids, carotenoids, chlorophylls, proteins, polysaccharides, etc.

[0040] Spirulina platensis G. extracts are also commercially available, e.g. VegeBrite® from Givaudan or Spirulina Extract (Phycocyanin from ZHEJIANG BINMEI Biotechnology Co. Ltd.).

[0041] The Spirulina platensis G. extract may optionally be purified prior to use in the pigment of the invention.

[0042] The Spirulina platensis G. extract used in the pigment of the invention is micronized. It has been found that micronization has a positive impact on chroma and coverage.

[0043] 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.

[0044] 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. In an embodiment, the micronized Spirulina platensis G. 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.

[0045] In an embodiment, the micronized Spirulina platensis G. 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.

[0046] Depending on the intended use or application, the ratio between the micronized Spirulina platensis G. 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.

[0047] In an embodiment, the weight ratio of micronized Spirulina platensis G. extract to kaolinite clay is from about 1 :2 to about 2:1 , more preferably from about 1 :1.5 to about 1.5:1 , and most preferably 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.

[0048] The pigment of the invention typically has a blue color, with varying shade depending on the concentrations of the components used.

[0049] For example, the pigment may provide a blue color similar to Pantone 2183 U (CMYK: 67; 22; 0; 27 / / sRGB: 62; 145; 186 / / Hex: #3E91 BA 11 Light Reflectance Value (LRV) = approx. 24).

[0050] The shade will also somewhat vary depending on the amount of pigment used in a cosmetic formulation.

[0051] 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) or zinc oxide for obtaining a lighter shade or CI77007 Ultramarines, Blue 1 Lake or Carbon Black (Cl 77268:1 ; charcoal) to obtain a darker shade.

[0052] It may also be mixed with other pigments to obtain mixed colors, for example purple by mixing with a red pigment or green by mixing with a yellow pigment. Preferably, such other pigments are also of natural origin.

[0053] The pigment of the present invention may further comprise a suitable carrier. Therefore, in an embodiment of the present invention, the pigment of the present invention further comprises a polysaccharide (e.g. maltodextrinor hydrolyzed corn starch), gum arabic, starch, cellulose, silica, calcium stearate, calcium carbonate, tricalcium phosphate, glucose syrup, or any other suitable carriers or mixtures thereof.

[0054] In an embodiment, the pigment of the invention comprises a polysaccharide, more preferably hydrolyzed corn starch. Such a carrier may already be included for a spray drying step, if applicable, and allows for improving the flowability and for avoiding caking and stickiness. Typically, if hydrolyzed corn starch is included, it is included in slightly higher amounts than the Spirulina platensis G. extract and the kaolinite clay.

[0055] For instance, the concentration of micronized Spirulina platensis G. extract in the pigment can be from about 20 wt% to about 35 wt%, more preferably from about 25 wt% to about 30 wt%, for example about 50 wt% of micronized Spirulina platensis G. extract.

[0056] For instance, the concentration of the kaolinite clay in the pigment can be from about 20% to about 40%, more preferably from about 25% to about 35%, for example about 30% of kaolinite clay.

[0057] For instance, the concentration of the hydrolyzed corn starch in the pigment can be from about 35% to about 50%, more preferably from about 40% to about 45%, for example about 42% of hydrolyzed corn starch.

[0058] In an embodiment, the pigment comprises from about 20 wt% to about 35 wt% of micronized Spirulina platensis G. extract, from about 20 wt% to about 40 wt% of kaolinite clay, and from about 35 wt% to about 50 wt% of hydrolyzed corn starch; more preferably comprising from about 25 wt% to about 30 wt% of micronized Spirulina platensis G. extract, from about 25 wt% to about 35 wt% of kaolinite clay, and from about 40 wt% to about 45 wt% of hydrolyzed corn starch, for example about 28 wt% of micronized Spirulina platensis G. extract, about 30 wt% of kaolinite clay, about 42 wt% of hydrolyzed corn starch.

[0059] The positive effects of micronization have been discussed above.

[0060] In an embodiment of the present invention, not only the Spirulina platensis G. 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. 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.

[0061] In a second aspect, the present invention provides a cosmetic composition comprising the pigment of the invention and a cosmetically acceptable excipient.

[0062] Preferably, the cosmetic composition comprises the pigment of one or more of the specific embodiments outlined above.

[0063] 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, dispersibility, 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.

[0064] The cosmetic composition may take any physical form and may be produced in any solid, liquid, or semi-solid form useful for application.

[0065] 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.

[0066] 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.

[0067] In an embodiment, the cosmetically acceptable excipient comprises a mixture of castor oil with squalene and / or hemisqualene.

[0068] 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. 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.

[0069] In a preferred embodiment, the cosmetic composition of the invention is a lipstick composition, an eye shadow composition or a compacted powder composition.

[0070] Preferably, the cosmetic composition of the invention is anhydrous or at least essentially anhydrous. For example, the cosmetic composition may comprise less than 5 wt% of water, more preferably less than 4 wt%, still more preferably less than 3 wt%, even more preferably less than 2 wt%, and most preferably less than 1 wt% of water. For example, the cosmetic composition may comprise about 3 wt% to about 3.5 wt% of water. It has been found that the pigment of the invention is more stable in anhydrous or essentially anhydrous formulations.

[0071] The pigment of the invention was found to provide antioxidant, wound-healing and antimelanogenic activity.

[0072] In view of this biological activity, the pigment of the invention is also highly beneficial for skin care applications.

[0073] Therefore, in an embodiment, the cosmetic composition of the invention is a skin care composition.

[0074] The present invention is further illustrated by means of the following non-limiting examples:

[0075] Example 1 : Preparation of Pigment

[0076] Spirulina platensis G. extract is commercially available from several suppliers, for example from Givaudan (e.g. Vegebrite Ultimate Ice Blue, produced in France).

[0077] Kaolinite clay is commercially available from several suppliers, for example from Color Clay Natural S.L. in Spain.

[0078] In order to prepare the pigment of the invention, 280 kg of a purified Spirulina platensis G. extract powder (dried) were dispersed in 600 kg of tap water and 120 kg of kaolinite clay were added. The resulting mixture was stirred at 50 °C until homogenization (about 30 min). The thus obtained mixture was spray dried with a spray dry apparatus (Anhydro spx flow) and sieved (mesh size 1000 pm) to obtain 360 kg of powder. Micronization (e.g. by air jet micronization) of the powder afforded 342 kg of micronized powder.

[0079] The thus obtained pigment had a particle size distribution of Dv10 = 1.30 pm, Dv50 = 3.70 pm, and Dv90 = 7.54 pm.

[0080] Example 2: Characteristics of Pigment

[0081] Four different batches of pigments according to Example 1 were assessed and found to exhibit the following characteristics:

[0082] The phycocyanin content was measured by spectrophotometry. A suitable method is described in: Single laboratory valisation of a method for the determination of C-phycocyanin and allophycocyanin in spirulina (Arthrospira) supplements and raw materials by spectrophotometry, Yohsikawa and Belay, Journal of AOA International Vol 91 , N°3, 2008.

[0083] 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:

[0084] - the L* axis runs from 0 (black) to 100 (white)

[0085] - the a* axis (green / red direction)

[0086] - the b* axis (blue / yellow direction).

[0087] 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.

[0088] 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. 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.

[0089] Opacity is a measure of covering power, 100% opacity means full coverage.

[0090] 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.

[0091] 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°.

[0092] Example 3: Stability Testing Batch No. 1 from Example 2 was submitted to stability testing under various conditions. The results are shown in the following two tables:

[0093] As can be seen from the above, whatever the conditions, the pigment of the invention is very stable with a dE2000 that is below 1.5, which confirms that the color change is not visible to the eye. Example 4: Effect of Micronization

[0094] In order to assess the effect of micronization, samples of spirulina extract and kaolin (both commercially available) were micronized and compared to the respective non-micronized materials and to the pigment of the present invention (spirulina 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 gardenia-containing samples was determined using a particle size analyser Mastersizer 3000+ Ultra from Malvern Panalytical.

[0095] 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 purified spirulina extract, but has hardly any impact on the kaolin. Micronization also lead to a reduction of the b* value, i.e. an increase in blue color, for the spirulina-containing samples (sample 1 vs. 2 and 5 vs. 6), as did the addition of kaolin (sample 1 vs. 5 and 2 vs. 6).

[0096] 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. Photographs of the powder samples 1 , 2, 5, and 6 are shown in Figure 1 . As can be seen from these photographs, the micronization and / or the addition of kaolin led to a real difference in terms of the colorimetric parameters.

[0097] In order to assess the impact of the clay used, the following two commercially available clays were tested:

[0098] - Montmorillonite: CosWHITE™ (supplied by Argile du Velay)

[0099] - Kaolin: CosKAO™ (supplied by Argile du Velay)

[0100] - Illite: CosNUDE™ (supplied by Argile du Velay)

[0101] Purified spirulina extract, kaolin, montmorillonite, and illite respectively, were subjected to micronization to obtain comparative samples.

[0102] For the mixtures, 500 g of purified spirulina extract were dispersed in 2 kg of tap water, and 500 g of clay was added under stirring. The mixture was then spray dried to obtain non-micronized test samples, some of which were micronized to obtain the micronized test samples.

[0103] The colorimetric properties were measured through L,a,b measurements (Spectrocolorimeter Konica-Minolta 3600d (D65, L*, a*, b*, h, C*)).

[0104] As can be seen from the above table, the addition of Illite to the purified spirulina extract led to an increase in Lightness and a decrease in the b* value (more blue).

[0105] As can be seen from the above table, the addition of Kaolin to the purified spirulina extract led to an increase in Lightness, while causing a slight increase in hue and a slight increase in Chroma, as well as a decrease in b* (more blue).

[0106] As can be seen from the above table, the addition of Montmorillonite gave a different hue in comparison to the addition of Kaolin. Moreover, the Chroma was slightly higher with Kaolin than with Montomorillonite. In addition, a stability testing revealed that the combination with Kaolin is much more stable than that with Illite, in essentially all tested conditions, and a higher percentage of Kaolin gave better stability results with a dE2000 < 1 .5:

[0107] Example 6: Performance of Lipstick Compositions

[0108] In order to determine the coloring properties and performance in formulation, the pigment of the invention was formulated in a lipstick base at different concentrations of the pigment of Example 1 and with varying amounts of titanium dioxide (Samples 1-5). For comparison, Unipure Blue LC621 (Blue 1 Lake; synthetic pigment) and Unipure Blue LC680 (INCI: CI77007 Ultramarines & kaolin; mineral pigment) were also formulated in the same lipstick base (Samples 6 and 7), as well as Natpure Xfine Spirulina SL615 (Sample 8; Spirulina platensis extract & trehalose dihydrate).

[0109] Sample 9 has the same composition as Sample 1 , but was further spread on a contrast card. Samples 10 to 12 were also spread on contrast cards, and comprise the comparative pigments Unipure Blue LC621 (Sample 10), Unipure Blue LC680 (Sample 11) were also formulated in the same lipstick base and Natpure Xfine Spirulina SL615 (Sample 12), respectively, at 10 wt%.

[0110] 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.

[0111] 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.

[0112] The two phases were combined at 75 °C and blended in the turrax blender for 2 min. The obtained lipstick composition was cooled down to room temperature for 2 hours under magnetic agitation.

[0113] Finally, for Samples 9-12, 2 g of the thus obtained lipstick compositions were crushed between glass slabs and applied to a contrast card using a film applicator (film thickness: 50 pm). 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 between the different pigments in lipstick base. CR / opacity was only determined for Samples 9-12.

[0114] The results are shown in the following table:

[0115] The comparison of Samples 1 , 2, 3 and 4 demonstrated that the pigment of the invention provides access to a variety of shade of blue, depending on how much TiO2is included. Increasing the amount of TiO2allowed to increase the Lightness L* and to obtain a variety of hues (h).

[0116] A comparison of Sample 3 and Sample 6 demonstrated that the pigment of the invention provides the same hue (h) as a synthetic pigment, and the Chroma (C*) is even higher than that of the synthetic one. The combination of the pigment of the invention with a mineral pigment (Unipure LC680) - Sample 5 - allowed to increase the Chroma (C*) and the b* (more blue) in comparison with only the mineral pigment (Unipure LC680; Sample 7) or only the pigment of the invention (Sample 3).

[0117] On contrast cards, the pigment of the invention (Sample 9) gave the highest L* and the lowest b* value (most blue) in comparison to Samples 10, 11 and 12. 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:

[0118] As can be seen from the above, the pigment of the invention is really stable, with a dE2000 < 4 for all conditions. The lipstick compositions according to Samples 9 and 12 were further submitted to a stability study under different conditions. The results are shown in the following table:

[0119] As can be seen from the above, the pigment of the invention (Sample 9) was overall more stable than the commercially available alternative natural pigment (Sample 12). Example 7: Evaluation of Antioxidant Activity

[0120] The aim of this study was to evaluate the antioxidant activity of the pigment of the invention after oxidative stress exposure using the quantification of Reactive Oxygen Species (ROS) production by DCFH-DA method. The anti-oxidant activity was determined on keratinocytes.

[0121] Cell Culture and Treatment

[0122] The cell culture was done on primary cells freshly isolated from biopsies. Normal Human Epidermal Keratinocytes (NHEKs) were seeded in a black plate with a glass bottom at 20’000 cells per well with a type I collagen pre-coating in quadruplicate. The cells were incubated for 24 hours in complete medium (Dermalife medium supplemented with Life factors K, Cell Systems) at 37 °C with 5% CO2.

[0123] After 24 hours of culture, the cells were treated in complete medium with the following conditions:

[0124] The test substances were diluted in culture medium.

[0125] Skin cells untreated and cultivated with complete medium were used as a negative control.

[0126] Cells were then incubated for another 24 hours at 37 °C, 5% CO2.

[0127] ROS Measurement

[0128] After 24 hours of incubation, the 2',7'-Dichlorofluorescin diacetate (DCFH-DA, Sigma, ENA490047502) probe was added to the wells at 50 pM for at least 30 to 45 minutes at 37 °C.

[0129] Cells were then washed two times with PBS buffer and treated with the oxidative stress (tert-Butyl hydroperoxide solution (TBP) at 5 mM (Sigma) in PBS buffer. The untreated cells remained in PBS buffer.

[0130] Finally, the emitted fluorescence was measured in darkness by excitation wavelength at 488 nm and emission wavelength 525 nm with a microplate reader (Spark®, TECAN).

[0131] Statistical Analysis A Shapiro- Wilk normality test was performed to evaluate whether the data follow the Gaussian Law. The results did not follow the Gaussian Law.

[0132] As a consequence, a non-parametric statistical analysis was performed by Kruskal-Wallis ANOVA, followed by Mann Whitney U test. Results were considered as significant with p<0.05 with *, p<0.01 with **, and p<0.001 with ***.

[0133] Results

[0134] The results are expressed in % of the untreated condition + TPB stress and are shown in the following table:

[0135] The results confirmed that TBP, which was used to induce oxidative stress, significantly promoted the formation of ROS (reactive species oxygen) compared to the untreated condition by +69%*.

[0136] The pre-incubation with resveratrol at 200 pM was used as a positive reference and was found to significantly reduce ROS production by -67%*.

[0137] These first observations allowed the validation of the model.

[0138] In the same condition, the spirulina extract used in the blue pigment of the invention led to a significant reduction of ROS production by -44%*.

[0139] Thus, the blue pigment of the invention exhibited an antioxidant activity on NHEKs with dose depending effect. Higher performance was observed at a concentration of 0.5 mg / ml, while 0.1 mg / ml provided a lower antioxidant activity.

[0140] 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). Cell Culture and Treatment

[0141] 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 hours 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 hours in complete medium (Dermalife medium supplemented with Life factors K).

[0142] After 48 h of culture, the cells were stimulated for 5 days with the following conditions:

[0143] The test substances were diluted in a basal medium without supplements (Dermalife medium supplemented with 1 % w / v antibiotics). Every two days, the treatments were renewed.

[0144] The addition of L-tyrosine at 1 mM and a-MSH at 1 nM allowed the authors to evaluate the whitening activity of the Blue Pigment.

[0145] Melanin Extraction and Dosage

[0146] 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.

[0147] In parallel, a standard range of eight concentrations of melanin was prepared (0 to 100 pg / ml).

[0148] Microtubes of samples and standard range were heated for 1 hour at 80 °C in a dry bath.

[0149] After the heating step, 100 pl of each sample was transferred to a 96-wells plate.

[0150] Optical density was measured at 405 nm with a microplate reader (Spark®, TECAN). Statistical Analysis

[0151] A Shapiro- Wilk normality test was performed to evaluate whether the data follow the Gaussian Law. The results did not follow the Gaussian Law.

[0152] 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 ***.

[0153] Results

[0154] The presented results are expressed in % of the untreated condition and are shown in the following table:

[0155] The melanogenesis control induced a significant increase of melanin synthesis by +8%.

[0156] The whitening control induced a significant decrease of melanin synthesis by 39%*, in comparison to the melanogenesis control.

[0157] These results validated the experiments.

[0158] In the same conditions, the blue pigment of the invention significantly inhibited the melanin synthesis by -32%*.

[0159] These results show that the pigment of the invention at 0.1 mg / ml exhibits a whitening activity under these experimental conditions. Effect

[0160] The aim of this study was to evaluate the wound healing effect of the pigment of the in a culture of keratinocytes. To this end, a percentage of cell migration surface was assessed after scratching the cell layer and after 8 hours of wound induction.

[0161] Cell Culture and Treatment The cell culture was realized with primary cells isolated from fresh biopsies. Normal Human Keratinocytes (NHKs) were seeded in a type I collagen pre-coated 24 wells-plate at 50’000 cells per well in quadruplicate. After 48 hours of incubation in complete medium (Dermalife medium, supplemented with Life factors K, Cell Systems) and 1 % of antibiotics (Sigma-Aldrich) at 37 °C with 5% CO2, the cells were rinsed twice with PBS (Gibco) and incubated for another 8 hours in basal medium. At the end of the incubation, the cells were treated overnight with the active ingredients at 37 °C with 5% CO2.

[0162] The cells were treated in basal medium with the following conditions:

[0163] The test substances were diluted in culture medium.

[0164] Skin cells untreated and cultivated with medium were used as a negative control.

[0165] The next day, 30 minutes prior to the scratch, a solution of calcein AM (Ref ab141420, Abeam) at 1 pM was added in the supernatant, in order to label the living cells. Then, a scratch was realized manually using a culture cone on the cell layer and then rinsed twice with PBS in order to eliminate floating cells. The cells were again treated with the previous conditions.

[0166] Pictures were taken immediately (x4 magnification, PICO, Molecular Devices) and after 8 hours and after 24 hours of incubation at 37 °C with 5% CO2.

[0167] Quantification of Scratched Area and Cell Migration

[0168] The area of scratch was measured on the pictures using the Imaged software (Java 1.6).

[0169] Statistical Analysis

[0170] A Shapiro- Wilk normality test was performed to evaluate whether the data follow the Gaussian Law. The results did not follow the Gaussian Law.

[0171] 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 ***.

[0172] Results The presented results are expressed in % of the untreated control and are shown in the following table:

[0173] The pre-treatment with the positive reference (Heparin-binding EGF-like growth factor = HB-EGF at 1 ng / ml) significantly increased the percentage of closing by +103%* after 8 hours and by +93%* after 24 hours in comparison to the untreated condition. These results confirmed the responsiveness of the model.

[0174] In the same conditions, the blue pigment of the invention significantly increased the keratinocytes migration by up to +122%* (after 8 hours).

[0175] These results show that the pigment of the invention at 0.1 mg / ml exhibits a wound healing activity under these experimental conditions. in Cosmetic Formulation

[0176] 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%.

[0177] The colorimetric properties of the resulting lipstick compositions were measured using a Spectrocolorimeter Konica-Minolta 3600d (h, C*), and the coverage (= Contrast Ratio Opacity; Cr; Cr(%) =((Y black*100 / Y white), with Y being the luminance or brightness).

[0178] As can be seen from the above, the coverage of the formulations increased drastically with micronization. And also the chroma increased.

[0179] Figure 2 shows photographs of the above formulations spread out on contrast cards. 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*), and the latter two even contained some visible particles.

[0180] Thus, overall, the pigments of the present invention exhibit a significantly better coverage and also provide the desired blue color.

Claims

Claims1. Pigment for use in cosmetic applications, comprising micronized Spirulina platensis G. extract and kaolinite clay.

2. Pigment according to claim 1 , wherein the Spirulina platensis G. extract comprises from about 45 wt% to about 75 wt% of phycocyanins, more preferably from about 50 wt% to about 70 wt% of phycocyanins, and still more preferably about 60 wt% of phycocyanins, based on the total weight of the Spirulina platensis G. extract.

3. Pigment according to claim 1 or 2, wherein the micronized Spirulina platensis G. 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.

4. Pigment according to any one of claims 1 to 3, wherein the micronized Spirulina platensis G. 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.

5. Pigment according to any one of claims 1 to 4, wherein the weight ratio of micronized Spirulina platensis G. extract to kaolinite clay is from about 1 :2 to about 2: 1 , more preferably from about 1 : 1 .5 to about 1.5:1 , and most preferably about 1 :1.

6. Pigment according to any one of claims 1 to 5, wherein the pigment has a blue color.

7. Pigment according to any one of claims 1 to 6, further comprising a polysaccharide, more preferably hydrolyzed corn starch.

8. Pigment according to any one of claims 1 to 7, comprising from about 20 wt% to about 35 wt% of micronized Spirulina platensis G. extract, from about 20 wt% to about 40 wt% of kaolinite clay, and from about 35 wt% to about 50 wt% of hydrolyzed corn starch; more preferably comprising from about 25 wt% to about 30 wt% of micronized Spirulina platensis G. extract, from about 25 wt% to about 35 wt% of kaolinite clay, and from about 40 wt% to about 45 wt% of hydrolyzed corn starch, for example about 28 wt% of micronized Spirulina platensis G. extract, about 30 wt% of kaolinite clay, about 42 wt% of hydrolyzed corn starch.

9. Pigment according to any one of claims 1 to 8, wherein at least all solid components of the pigment are micronized.

10. Cosmetic composition comprising the pigment according to any one of claims 1 to 9 and a cosmetically acceptable excipient, in particular a cosmetically acceptable excipient comprising castor oil.

11. Cosmetic composition according to claim 10, which is a make-up composition, and in particular a lipstick composition, an eye shadow composition or a compacted powder composition.

12. Cosmetic composition according to claim 10, which is a skin care composition.

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