WO2001055263A1

WO2001055263A1 - New coated pigments and composition containing them

Info

Publication number: WO2001055263A1
Application number: PCT/IB2000/001618
Authority: WO
Inventors: Carlo Ghisalberti
Original assignee: Carlo Ghisalberti
Priority date: 2000-01-28
Filing date: 2000-11-07
Publication date: 2001-08-02
Also published as: WO2001055262A1; AU2000279412A1; IT1317743B1; AU2000279411A1; ITMI20000120A0; ITMI20000120A1

Abstract

The present invention relates to new coated pigments comprising an inner core of colored inorganic pigments and an external coating of vegetal lakes, processes for the preparation of said coated pigments and eudermic cosmetic and make-up compositions comprising them.

Description

NEW COATED PIGMENT AND COMPOSITION CONTAINING THEM

FIELD OF THE INVENTION

The present invention relates to new coated pigments comprising an inner core of colored inorganic pigments and an external coating of vegetal lakes. The present invention also relates to processes for the preparation of said coated pigments and eudermic cosmetic and make-up compositions comprising said coated pigments, as well as to pharmaceutical and food products comprising said coated pigments.

BACKGROUND OF THE INVENTION The use of cosmetic products for make-up date back to ancient time.

Presently the cosmetic science has developed a variety of sophysticated make-up compositions showing high quality aestethic effects.

Most of the present make-up compositions, particularly those for the periocular zone, contain inorganic pigments. Preferred inorganic pigments are the thermo- and photochemically stable iron oxides, available in the main colors, whose proper combination with white pigments allows the formulation of many desired make-up formula.

Other inorganic pigments are chromium and manganese compounds, which are transition metals similar to iron thus bearing a multiplicity of oxidation levels. These metal compounds display catalytic redox properties, therefore promote oxidative stress on skin by activating Fenton-like reactions which generate harmful free oxygenated radicals. The contact of iron and of the transition metals actually promote oxidative burdens and skin ageing, particularly when combined with light radiations, as described by Jurkiewicz B.A. and Buettner G.R. in Photochem Photobiol, 64(6):918-22 (1996).

An first approach to the amelioration both end-use performance and the decrease of skin ageing due to the pigment has consisted in their coating with lipophilic substances. For example, silicones was used in US.5458681, hydrogenated lecithin in US4622074, with fatty soaps in US4648908, silicone-containing compound and fatty acid ester in US05738841, hydrogenated lecithin in US4622074, in US6080424 by natural phospholipid and proteins.

Nonetheless, such lipid coatings may be depleted during the mixing steps at high temperatures required in order to melt the solid waxes and fats during the make- up manufacturing.

The pigments intended for the make-up may be coated pigment by a poly- olygomeric film, such as in EP00340103 by a crosslinked polybet alanine and polyhydric alcohol, in WO09426711 by carbazol derivatives, in US6004541 by perfluoridated-derivatives, in US5989570 by a plasticizing oligomer plus a film- forming polymer, in US5968496 by an imidazolium derivative and a branched polyethylene glycol, in US5091013 by carbozylated polymers, and other synthetic compounds such as in US5788955, US5961989, WO09636323, EP00875243.

Ideally, said cosmetic pigments should performe additional protectant actities when the make-up formulations contaning them are applied to the skin. Based on the above, a cosmetic make-up composition containing pigments showing non-aggressive behaviour and also characterized by a high mechanical stability throughout the manufacturing steps would be of great interest. Said pigments should be further characterized by good stability during storage and handling of the make-up compositions. DETAILED DESCRIPTION OF THE INVENTION

One of the purpose of the present invention is to avoid skin ageing due to the action of iron, chromium or manganese compounds which are present in pigments commonly used for decorative purposes in make-up compositions.

We have now found that the common inorganic pigments used in make-up preparations may be coated with vegetal complexes. The coated pigments of our invention may be produced by known laquering procedures with selected vegetal substances, so that the pro-oxidative inorganic compounds are excluded from the direct contact with the skin.

Therefore, the present invention relates to new coated pigments comprising: a) an inner core of a colored inorganic pigment and b) an outer layer of at least one vegetal substance in the form of a complex with at least one lake-forming ion.

In the following description, the new coated pigments are called "phytocoated pigments".

The whole phytocoated pigment is a solid colored particle which is unsoluble in either aqueous or oily medium.

Hence, according to the invention, the inner core (a) is an inorganic pigment commonly used in cosmetic make-up whose surface is coated with a thin film of an inert vegetal complex (b), having preferably the same color of the underlying pigment, in order to reinforce the chromatic tone of the base pigment (a).

Suitable inorganic pigments for the purposes of the present invention are the transition-metal pigments such as iron ^II) and/or iron^{(I T)} oxides and hydrated oxides, clay colored with iron oxides, prussia blue, chrome ^III oxide and hydroxide, manganese^{(II m)} phosphates, and other mixed compounds.

Illustrative examples of the inorganic pigments according to the invention are the iron oxides such as FeO (yellow), FeO+Fe2θ3+Al₂θ_3*nH₂O (orange and red),

Fe₂O_3*nH₂O (red), FeχO_y (brown), Fe₃O (black); ferric ferrocyanide (NH₃Fe[Fe(CN)₆]); chromium oxides such as Cr₂O_3*nH₂O and Cr₂O₃; and manganese pyrophosphates such as (NH3)₂Mn₂(P₂O )2 and Mn₃(PO ) .

Other suitable inorganic pigments include miscellaneous earths such as vivianite sepia, sienna earth and sienna burnt, earth umber and burnt umber, amethyst, mars violet, as well as and ultramarines, complex sulfosilicates of approximate formulae Na₇Al₆Si₆O₂ S3 or 2Na Al₂Si2O₆*NaS2, therefore containing minor amount of transition metals.

According to the invention, the outer layer (b) is a complex of a vegetal substance with a with at least one lake-forming ion, said complex being preferably carefully selected in order to match and reinforce the chromatic hue of the underlying inorganic pigment. Alternatively the outer layer (b) might have a neutral color; in this case, the color of the inorganic pigment is still evident at the surface of the coated pigment and the outer layer (b) just acts as a protective coating.

Suitable vegetal substances for the purposes of the present invention are those selected among plant molecules capable of forming stable complex with the lake- forming salts. Accordingly, said vegetal substances shall own at least one carbonyl group and one hydroxyl group, in vicinal or adjacent position (e.g. on two condensed aromatic rings; on position 4 and 5 of a flavonoid structure; on a beta-diketo- aliphatic chain) so to allow the formation of a bidentate complex with the lake- forming ions; their ketoenolic synthones may also be used.

The vegetal substances preferably show poor solubility in water and a good solubility in an alkaline medium from which they be precipitable by acidification at a pH 7. The vegetal substances whose characteristics meet the above-indicated requisites belong to the following groups: - flavonoids

- benzindenopyranones

- open ring polyphenols

- quinones chlorophyllins - vegetal melanins

The flavonoids are a large class of vegetal substances. Illustrative examples of flavonoids are those contained in grape and in the peel of other edible fruits, thus containing flavanonols such as myricetin, flavones such as luteolin, flavandiols such as dihydroquercetin, as well as the flavanols. Grape contains also the anthocyanins and chalcones, which are the biosynthetic precursors of flavonoids and anthocyanins, the latter being slowly reverted to the corresponding chalcones when kept in neutral or slighly alcaline aqueous solution. Anthocyanins are the coloured matter of flowers and also occurring in coloured fruits and vegetables, including cyanidin and delphinidin, which may also be substituted as mono, di-saccharides, and position 3 may be acylated, e.g. with p-coumaric acid. Further illustrative examples of flavonoids are the oligomeric proanthocyanidins (OPC), precondensed oligomer of flavanols, i.e. (+)-catechin and (-)-epicatechin, which are commonly extracted from grape seed, pine bark, cocoa and other vegetal sources rich in flavan-3-ols in the free, glucosylated, esterified, or condensed forms. Galloylated catechin monomers are typically extracted from green tea or Catechu gambir, which contain (+)-gallocatechin (GC), (+)-gallocatechin gallate (GCG), (-)-epigallocatechin (EGC) and (-)-epigallocatechin gallate (EGCG).

Further illustrative examples of flavonoids are the flavanones and flavonols, also known as citrus bioflavonoids because of the high content thereof in Citrus spp, although being widely found throughout the plant kingdom. Flavanones such as hesperetin, naringenin and glycosides thereof are typically found in citrus peels. An almost ubiquitary flavonols is quercetin, quit widespread in plants although being conveniently extracted from Aesculum hippocastanum whose glycosides include the 3-rhamnoside (quercetrin) and the 3-rutinoside (rutin), the latter occurring in a variety of plants, including tobacco, tea, eucalyptus, grapes, etc., being commercially available in highly purified forms from several vegetable sources. Other flavanones include myricetin, kaempferol, fisetin, the latter is found in admixture with fustin in Venice sumac.

Mixed flavonoids are found in several plants, such as morin and maclurin (which is a benzophenones) in old fustic (Morus tinctoria), chrysin from the heartwood of Pinus monticula, or the complex flavonoid mixture found in Chrysanthemum and goldenrod.

The vegetal substances preferably show poor solubility in water and a good solubility in an alkaline medium, from which they be precipitable by acidification at pH between 9 and 7 or lower.

Other vegetal compounds which are suitable for our purposes include the plant polyphenols which are biogenetically correlated with flavonoid, e.g. the benzyndenpyranones, i.e. polycyclic substances typically occurring in some tropical plants. Illustrative examples are the pentahydroxy-7,l lb-dihydrobenz[b]inden-[l,2- d]-pirane, i.e. haematoxyilin and its oxidized form (haematoxyilein), thereby obtainable from logwood; the tetrahydroxy- analogues, i.e. brazilein and brazilin, thereby obtainable from Cesalpinacee spp., such as brazilwood and sappanwood. A tetracyclic fused-ring moiety is represented by santalines, extracted from red sandalwood, and by santarubines, from Baphia nitida or the varieties of Pterocarpus (P. osun, P. soyauxii) found in West Africa.

Among preferred cosmetic ingredients there may be pigment and dyes of natural and synthetic origin to complement the color of make-up compositions. Illustrative examples of synthetic pigment and dyes are organic the D&C organic colorants generally used in cosmetics, such as CI 45,170, CI 15,585, CI 45,380, CI 15,510, CI 45,370, CI 45,410; CI 15,630, CI 15,850:1; CI 15,850:2, CI 19,140, CI 12,085, CI 45,425, CI 15,985, CI 73,360, CI 45,430, CI 77,266, CI 75,470. Illustrative examples of natural and semi-synthetic pigment and dyes are carotenoids, xanthophyll, caramel, vegetal charcoal, natural and synthetic eumelanins, carmine, red yacca gum, dracorubin (dragon blood), monascus red, and further vegetal or animal colors.

Illustrative examples are brazilein and hydroxybrazilein, the former obtained from Cesalpinacee spp. such as brazilwood and sappanwood, the latter is also know as haematoxyilin and commonly extracted from logwood.

Other vegetal compounds suitable for our purposes also include the phytoalexins (open ring polyphenols), for instance dihydroxyphenols such as hydroxytyrosol and its esters (oleuropein, verbascoside, etc.) found in olive fruit and leaves; protocathechuic acid found in most higher woody plants and in wheat; and protocathechuic aldehyde, found in vanilla.

Further illustrative examples of open ring polyphenols are gallic acid and its derivatives, which may be obtained from hydrolysis of plants rich in tannins, such as nutgalls. Tannins (alias tannic acid) are also classified as ellagitannins or gallotannins, the latter releasing gallic acid by hydrolysis treatment. Gallic acid, in the form of its aluminium or calcium complex, is particularly suitable to obtain an outer layer (b) showing a neutral color.

Other vegetal compounds suitable for our purposes include the vegetal quinones, which comprise anthraquinones, dianthrones, and naphtoquinones Illustrative vegetal anthraquinones are rhein, emodin, aloe-emodin, parietin, the frangulines, crysophanol and its glucoside (crysophanein), the cascarosides, and the reduced forms (anthracenons and anthrols) and glucosides thereof, occurring in different proportion in rhubarb, senna, cascara and frangula, as well as in some lichens; aloin and aloe-emodin from aloe; and morindon from Coprosma australis. The anthraquinones are historically represented by alizarin and related compounds, such as ruberetic acid and purpurin, from Rubia tinctoria and other rubiacee.

Illustrative vegetal quinons are the dianthrones, i.e. dimeric anthrones such hypericin from Hypericum p. and the sennosides from senna.

Further illustrative vegetal quinones are napthtoquinones such as lawsone from henna; juglone from walnut; alkannin from Alkanna and its enantiomer, shikonin; the lapachols from Tabebuias spp. (e.g. "pau d'arco"); and plumbagins from Plumbago spp.

Other vegetal compounds suitable for our purposes include chlorofillines. The well-known metal-porphyrines are ubiquitary pigments of the green plants, which contain chlorophyl A and B, converted by the hydrolysis of the phytolic residue and/or by ion exchange in the water-soluble Mg-chlorophyillin (olive green) and Cu- chlorofillin (bright green). Source of chlorofϊllins for our purpose are the commercially available Mg - or Cu-chlorofillins (food color E-140). Nevertheless, hydrolized vegetal extracts rich in chlorophyl can be used. Other vegetal compounds suitable for our purposes are the vegetal melanins.

Examples of vegetal melanins are the "phytomelanins" resulting from the polymerization of plant polyphenols, and the micomelanins called "naphtomelanins", i.e. the broad photoabsorbing biopolymers containing naphthalene groups, which are typically produced by selected fungi strains. Suitable phytomelanins for the purpose of the present invention may be either extracted from plant sources, as disclosed in WO00/09616, or more conveniently obtained by synthesis from vegetal monomers alone, in combination or in conjunction with eumelanin precursors, as disclosed in our copending application PCT/TBOO/01276.

Suitable micomelanins for the purpose of the present invention may be either extracted from fungi, or more conventiely obtained by chemical or enzymatic synthesis from dihydroxynaphthalene alone, in combination or in conjunction with eumelanin or phytomelanin precursors, as disclosed in our pending application MI2000A1513.

The vegetal compounds suitable for our purpose may occur either in the free form (aglycones) or as natural occurring esters and ethers (e.g. glycosides, gallates, and the like) as well as in oligomeric form ( e.g. proanthocyanidins and viniferins).

Glycosides are the O-derivatives of the plant polyphenols in the plain form (aglycones), generally substituted in one or two hydroxy groups in the 3, 5 or 7 positions with naturally occurring mono- di- or trisaccarides, such as ruthoside, galactoside, rhamnoside, glucoside, sophoroside, rhamnoglucoside, and the like.

According to a preferred aspect of the present invention, the vegetal compounds may be in form of titolated plant extracts with known chemical composition, such as those obtained by standardized extraction methods from vegetal sources, either in solid form, e.g. dry extracts, or in liquid form, e.g. hydroalcoholic or alkaline solution.

Even though other vegetal substances may be used, the afore mentioned ones are particularly preferred for make-up compositions due to the best balance of optimum requisites: the photostability of the unsoluble complexes, the availability of the extract or purified fractions or the isolated pure compound as well as the synthetic equivalent. The vegetal compounds as enriched fraction or even as pure compounds offer the advantage of producing coated pigments particularly stable and with bright color. For that purpose, the vegetal complex were produced by precipitation on a white inorganic pigment, such a∑, allumina, in order to fully evaluate their color tone, intensity and resiliance. Thanks to this pre-screening, which is disclosed in our copending application MI2000A00129, the phytocoated pigments of the invention are characterized by intense and stable color tones.

According to the present invention the term "lake-forming ions" designates inert ions which can form polydentate complexes with the aforementioned vegetal substances.

Suitable lake-forming ions are those selected among water soluble salts of aluminium and zinc in either cationic or amphoteric form, as well as from titanium and alkaline-earthy metal salts. In some cases, tin salts from soluble stannous (Sn² ) and stannic (Sn⁴⁺) salts may be used as lake-forming ions.

Examples of such salts are the sulfates, nitrates, chlorides and acetates of aluminium, zinc, titanium, magnesium, calcium, strontium and barium salts. Further example of the inert metal salts are some alkaline amphoteric complexes, such as sodium or potassium aluminate and zincate.

In a particularly preferred embodiment of the present invention, said salts are reacted with an alkaline solution comprising the vegetal substances, and the acid- base reaction provides soluble non-toxic salts (e.g. NaCl) which can be washed away from the insoluble precipitated complex, i.e. the phytocoated pigment.

The phytocoated pigment of the present invention may be prepared by laquering procedures which are well known to those are skilled on the art.

A preferred procedure is the direct precipitation. In this case the inorganic pigments are suspended in a solution formed by the alkaline salts of the vegetal substance, then the phytocoated pigments are precipitated by adding said suspension to a solution of at least one lake-forming ion, e.g. the soluble acidic salt of the Al,

Zn, Ti, alkaline-earthy metals, or of mixture thereof.

Further preferred methods are based on co-precipitation or pre-coating procedures. An illustrative example of these procedures comprises the solubilization of both the vegetal substance (in the form of an alkaline salt) and the aluminium or zinc ions, as sodium or potassium aluminate or zincate. The inorganic pigment is then suspended in the alkaline solution and gradually brought to a pH between 9.5 and 10.5 by the addition of a mineral acid. The soluble acidic salts of Al, Zn, alkaline-earthy metals (e.g. CaCl₂) or mixture thereof are then slowly added to the warm slurry, finally neutralized with a mineral acid.

A further example of this procedure comprises the pre-coating with Al³⁺, Zn²⁺, Ti⁴⁺ or alkaline-earthy oxide-hydroxides, formed by suspending the inorganic pigment in water, heating at 40-90°C, followed by the addition of an aqueous acidic solution of a water-soluble salt of Al or Zn. Simultaneously, a mineral alkali or acid is added to mantain pH around 5 to 9 until the precipitation takes place, then the pigment slurry is laked by precipitation of a vegetal substance with soluble acidic salt of the Al, Zn, alkaline-earthy metals, or mixture thereof, in order to form a firmly adhering vegetal lake.

The phytocoated pigments of the invention may be also produced by other lacquering techniques.

An example of lacquering techniques includes the formation of complexes by the use of alkaline-earthy hydroxides, i.e. by mixing a reactive suspension of the lacquering salt(s) (e.g. Ca(OH)₂) with a slightly alkaline or hydroalcoholic solution of the vegetal substances, followed by neutralization by addition of an inorganic acid, bicarbonates or carbon dioxide solutions.

Other examples of lacquering techniques are those which make use of the vegetal substances in neutral or slightly acidic aqueous solution, therey suspended or solubilized by heating, for examples at 70° to 95°C. This solution is added with the inorganic pigment and stirred at this temperature untill at least part of the vegetal substance are absorbed onto the inorganic pigment. The soluble salts of lake-forming ions (also known as mordants) are then mixed under stirring, the slurry is heated and stirred, eventually neutralized, to provide the phytocoated pigment of invention.

Another examples of laquering techniques are those where the lake-forming ions (mordants) are first reacted with the inorganic pigment in a aqueous suspension at high temperature (e.g. 50° to 95° C), then added with the solution or suspension of vegetal substances in neutral or slightly acidic aqueous or hydroalcoholic solution, thereby stirred and eventually neutralized, to provide the phytopigments of invention. The phytocoated pigments of the invention may be also produced by other lacquering techniques which are well-known to those skilled in the field. The use of different laquering techniques do not substantially modify the pigmentary features of the products obtained according to the present invention.

It may be useful to carry out a hydrolytic and or oxidative pre-treatment of the vegetal substance prior to use. For example the anthraquinoids kept in alkaline solution with a slow stream of air increase the anthraquinones content by the oxidation of the reduced forms (anthranols and anthrones), or enhance the haematoxyilin/haematein ratio in the logwood extract. The anaerobic alkaline pre- treatment may also increase the redness of proantocyanosides and the browness of catechins; or convert the blue-violet anthocyanins in the yellow-green chalcones; or fully hydrolizes extract containing chlorophylls into chlorophyllins. The slurry of phytocoated obtained in aqueous suspension shall be then washed, dried and finally micronized. The washing may be carried out with water or carbonate solution (CO₂ or NaHCO₂ aqs) at any temperature from about 20 to 90°C. A final washing with a water-soluble organic solvents (e.g. aceton) may be applied to speed the drying step up. The drying may be carried out at any temperature between 30 and 150°C, preferably at 80-130°C and under vacuum or by atomization, followed by grinding. The micronization is generally not applied since the base pigment used for the coating are preferably used as micron-like size particles.

The invention also relates to cosmetic or dermatological compositions comprising the coated pigments described above. The wide color range of the phytocoated pigments of the present invention allows the preparation of a variety of cosmetic compositions.

The make-up compositions according to the invention may also comprise any cosmetically acceptable ingredients. The expression "cosmetically acceptable ingredients" designate in the present specification products which are suitable for their use in cosmetic treatments, for example those included in the LNCI list drawn by the European Cosmetic Toiletry and Perfumery Association (COLIPA) and issued in 96/335/EC "Annex to Commission Decision of 8 May 1996".

Among preferred cosmetic ingredients there may be pigment and dyes to complement the color of make-up compositions, for example synthetic organic lakes and dyes, carotenoids, xanthophyll, caramel, vegetal charcoal (Carbo vegetabilis), sepiomelanin and synthetic eumelanins, carmine, dracorubin, monascus red, and further vegetal or animal colors.

The composition of the invention may comprise 0.1-99% of other cosmetically acceptable components such as oils, waxes, surfactants, silicones, perfluorides, other non-coated or differently coated powder, UV-absorbers, fragrances, dyes or coloured pigments, or other base materials as INCI. The base materials of natural origin are preferred in this invention, the ones of vegetal origin being more preferred.

Further preferred cosmetic ingredients to the face, eyes or lips may comprise from 5 to 98% by weight of a fatty body selected from the group consisting of an oil and a mixture of an oil and a wax, e.g. paraffin oil, petrolatum oil, mineral oil having a boiling point comprised between 310° and 410° C, purcellin oil, perhydrosqualene, calophyllum oil, sweet almond oil, palm oil, avocado oil, olive oil, ricin oil, wheat germ oil, dimethylpolysiloxane, butyl myristate, isopropyl myristate, cetyl myristate, isopropyl palmitate, butyl stearate, hexadecyl stearate, isopropyl stearate, octyl stearate, isocetyl stearate, decyl oleate, hexyl laurate, propylene glycol dicaprylate, diisopropyl adipate, oleyl alcohol, linoleic alcohol, linolenic alcohol, isostearyl alcohol, octyl dodecanol, isopropyl lanolate, isocetyl lanolate, glycol octanoate, glycerol octanoate, glycol decanoate, glycerol decanoate and cetyl ricinoleate, said wax comprising a member selected from the group consisting of a microcrystalline wax, paraffin wax, petrolatum wax, ozokerite, montan wax, beeswax, spermaceti wax, lanolin wax, lanolin alcohols, hydrogenated lanolin, hydroxylated lanolin, acetylated lanolin, lanolin fatty acids, alcohol of acerylated lanolin, candellila wax, carnauba wax, Japan wax cocoa butter, hydrogenated ricin oil, hydrogenated palm oil, hydrogenated tallow, hydrogenated coconut oil, polyethylene wax, propylene glycol monomyristate, myristyl myristate, silicone wax, cetyl alcohol, stearyl alcohol, mono-, di- and triglycerides solid at 25° C, stearyl monoethanolamide, rosin, glycol abietate, glycerol abietate, sucroglyceride, and the oleates, myristates, lanolates, stearates and dihydroxy stearates of calcium, magnesium, zinc and aluminium.

The phytocoated pigments of invention are characterized by a distinctive color (alias hue), by its chroma, which is the purity, saturation or intensity of a hue; as well as by its value, which is the extent to which a colour reflects or absorbs light. The phytocoated pigments also have a typical tinting strength, i.e. its dominant effect on a pigment mixtures, as each pigment is relatively transparent or opaque, thus affecting the final color when mixed with other pigment or filler. Those which reflect a greater quantity of light or have a high intensity make 'high key' colours.

The phytocoated pigments of our invention are generally characterized by a high tinting strenght, therefore the make-up composition comprising thereof shall make use of white pigments or fillers to attain light hue, i.e. low value chroma of a desired make-up color.

The phytocoated pigments of the invention can be employed alone or in combination with uncoated white pigments and fillers in cosmetic, such as make-up, compositions in any amounts between 0.1 and 70 % by weight. One or more kind of the phytocoated pigments, according to the different possible solutions of the invention, may be present in said compositions.

Typical make-up compositions are eye shadow pencils (pigment content from about 5 to 15%), mascara (pigment content from about 10 to 70%), eye shadow powder compacts (pigment content from about 20 to 70%), liquid compositions for eye shadow and eye makeup (pigment content from about 7 to 15%), lipsticks (pigment content from about 10 to 20%), lip gloss cream (pigment content from about 10 to 15%), make-up in pencil form (pigment content from about 15 to 25%), make-up powder compacts (pigment content from about 10 to 50%), make-up emulsions (pigment content from about 5 to 10%), make-up gel (pigment content from about 1 to 5%), sunlight protection emulsions and tanning emulsions (pigment content from about 5 to 10%), foam bath concentrates with color gloss (pigment content from about 0.1 to 2%), skin care lotions (pigment content from about 0.1 to 2%). In a further preferred embodiment of the present invention the phytocoated pigments may be eventually post-coated with further organic substances, the post- coating may be performed either on the wet phytocoated pigment or, more preferably, on the final phytocoated pigment after dying and grinding.

Illustrative examples of organic substances suitable for the post-coating treatment are silicone, triethanolamine stearate, sodium hexametaphosphate, lecithin and hydrogenated lecithin, fatty acid and alkaline or earthy-alkaline salts thereof, and mixture thereof. Further examples of organic substances suitable for the post-coating treatment are polymers such silicones, poly-beta-alanines, perfluoridated polymers, carbazole polymers, polyhydric alcohol, polyimidazoles, and mixture thereof. Any specific post-coating may offer a distinctive advantage and performance features. For example the post-coating with carboxypolymers pigment produce a higher power of holding moisture, the peptide olygomers improve the resistance to moisture by reducing the effect of stickiness by hydroscopicity while increasing the adhesion capacity of the make-up products; the organosilicones increase both water repellency and spreading; whilst the use of lecithin improve the skin adhesion. The post-coating with perfluoridated substances ameliorate the UV-protection; the polymer containing ethylenic unsaturation and acrylic, methacrylic, allylic, methallylic or vinyl homopolymers or copolymers increase the shelf life; the organosilicons enhance smooth feel and the adhesion to the skin; whilst silicone compounds in combination with hydrocarbon compounds improve the adhesion capacity of the make-up while possessing good cosmetic properties when applied to the skin. The post-coating with fatty acid soaps renders the phytopigments water- repellent while giving refreshment and/or smoothness to the cosmetic make-up comprising thereof. The substances used to carried out the post-coating onto the phytocoated pigments may need the presence of a soluble metal salt in order to be grafted to the pigment surface. Generally the quantity of lake-forming salts present in the outer layer of the phytocoated pigments is sufficient to perform the aforementioned task, otherwise a new layer of these salts may be formed afterwards.

The phytocoated pigments of the present invention are characterized by excellent lightfastness rating, capability of the pigment to resist fading (discoloration) when targeted with light radiations.

The invention also refers to the use of phytocoated pigments in food and pharmaceutical compositions.

The external phytocoating is in this case useful to avoid any contact between the inorganic pigment and the components of the food and pharmaceutical composition, which are therefore protected from the possible oxidation. In these compositions, which may be oral compositions, the phytocoated pigments are included for their coloring properties and can be further associated with an antioxidant behaviour to increase the shelf-life of the edible products comprising thereof.

The edible compositions comprising the phytocoated pigments of the invention include of course only pigments which are safe when orally administered, i.e. for instance, iron oxides.

The phytocoated pigments may be included in health food, dairy products and canned food, as well as in beverages such as soft drinks, syrups and fruit juice. The pharmaceutical and nutritional products comprising phytocoated pigments to be orally administered may be in any solid or liquid forms, and may also include further food ingredient and additives, as well as active ingredients and acceptable excipients, for examples those described in "Remington's Phaπnaceutical Sciences Handbook", Mack Pub. Co, USA.

In the following examples all parts and proportions are by weight and the solutions have 1M concentration, unless otherwise indicated. EXAMPLES A) Examples 1-13 - Phytocoated pigments on inorganic pigments

Into a beaker fitted with a mechanical stirrer, the vegetal substances are solubilized in a mixture of water and an appropriate amount of NaOH ION. Then a quantity of the inorganic pigment is admixed and suspended under stirring. This slurry is then mixed with an aqueous solution of the lake-forming ions ("precipitants") and the mixture is kept for 10 minutes under stirring. The slurry is then filtered and the filtrate is washed with warm deionized water, untill soluble salts are removed. Finally, the resulting cake is dried at 80°C and grinded, thereby obtaining a colored pigment powder.

A variety of phytocoated pigments are prepared with different kind of inorganic pigments, thus coated with the vegetal complex, previously selected by the criteria of best matching the original color of the inorganic core.

The vegetal substances used are either in the form of extracts or as highly purified active ingredients, and thereafter precipitated on the substrate, to provide phytocoated pigments as described in Table I.

H

Exam VEGETAL SUBSTANCES (a) NaOH INORGANIC PIGMENT (b) % Coating PRECIPITANT PIGMENT pie extract or pure substance quantity IO N FDA CI. q.ty (a)/(a+b)100 1M solution q.ty COLOR

N° (type / content) (g) (ml) Name N°. (g) (w/w %) (type) (ml) (aprox. definition)

1 Rutin trihydrate 95% 0,5 1 Iron oxide 77492 10 5% A1C1₃ 2 goldenroad

2 Hesperidin 90% 0,5 1 ,5 Iron oxide 77492 10 5% A1C1₃ 5 gold-yellow

3 Naringin 85% 0,5 1 ,5 Iron oxide 77492 10 5% AICI₃ 5 gold-yellow

4 Anthocyanins 50% 0,5 2,2 Iron oxide 77499 10 5% AICI₃ 7 black

5 Proanthocyanosides 90% 0,4 1,2 Iron oxide 77491 15 2,6% CaC ¹ 16 red-orange

6 Rhubarb 11% 1,6 2,4 Iron oxide 77491 14 10% CaCl/² 30 red-chocolate

7 Brazilwood extr.+Frangula 19% 0,5+1 3 Iron oxide 77492/1 15 9% AICI₃ 10 sienna

8 Phytomelanin (10% sol.) 1,5 1,5 Iron oxide 77492/1/9 15 9% AICI₃ 5 ochre-brown

9 Chlorophyllin-A+Gallic acid 0,3+0,9 1 Cr oxide green 77288 10 11% CaC^ 15 dark seagreen

10 Rutin 95%+ Anthocyanins 50% 0,3+1 1,5 Cr hydroxide green 77289 10 12% AICI₃ 5 hemeraldseagreen

1 1 Brazilwood extract 1,5 1 ,5 Manganese violet 77742 10 13% AICI₃ 5 rosy violet-red

12 Anthocyanins 50% 5 (20% sol) 1 ,2 Ultramarine 77007 4,5 18% AICI₃ 4 rosy plum

13 Anthocyanins 50%+Gallic acid 5(20%)+0,5 1,7 Prussia blue 77510 10 13% SrCl₂ 12 dark slateblue

Note on Table I:

- Phyomelanin (10% solution) was obtained by air injection onto a solution of L- dopa 9% w/v and protocatechuic acid 1% w/v in NaOH IN for 24h Example 14 - Phytocoated pigments by the use of amphoteric lake-forming salts Into a 500 ml beker fitted with a mechanical stirrer, 1 g of a rutin trihydrated is solubilized in a mixture of 200 ml of water and 12 ml of NaOH IN. The solution is heated to 50-60°C and added with with 3 g of NaAlO₂ (5 ml of 60 g/1 solution). An inorganic pigment dispersion consisting of 20 g of yellow iron oxide in 200 ml of water is then admixed. The slurry is kept under stirring for 30 minutes, then slowly acidificated by the dropwise addition of HCl 3N in 30 minutes at 50-55° C, until pH is stabilized at 10.5. The slurry is added with 6 ml water solution of CaCl₂ 0,5M. After 20 minutes under stirring, the slow acidification with HCl is carried out until pH 9-10, and then continued until neutral pH. The slurry is hot-filtered, washed with water, dried at 80°C and grinded, thereby obtaining a yellow pigment powder. Example 15 - Phytocoated pigments by preforming the lake on the substate

Into a 500 ml beaker fitted with a mechanical stirrer are suspended 6 g of yellow iron oxide in 200 ml of deionized water and heated, with stirring, to 75° C A NaOH IN solution is added to pH of 8 then 10 ml of solution A1C1₃ 1M is added dropwise together with NaOH IN, in order to throughoutly mantain the pH around 8. The slurry is stirred for 1 hour, then added with a solution of 1 g of a rutin trihydrated in 200 ml of water and 12 ml of NaOH IN. The slurry is heated under stirring at 80-90° C, hot-filtered, washed with water, dried at 80°C and grinded, thereby obtaining a yellow pigment powder. Post-coating Example 1 5 g of pigment of Example 3 are suspended in 5 ml of 4 % aqueous solution of Al₂(SO₄)₃, heated at 50° C and stirred for 15 minutes. Then 10 ml of 1% solution of lecithin in water kept at pH 9 (by diluted HCl) are slowly added to the mixture, which is stirred for 15 minutes at 50° C. The pigment is filtered, dried in oven at 80° and milled. Post-coating Example 2 5 g of pigment of Example 6 are suspended in 10 ml water under stirring and added with 0.1 g of hydrogenated lecithin is added, then the mixture is heated at 70° C untill complete dispersion of the lecithin. Then 1 ml of a 20% solution of ZnSO in water is slowly added and the mixture is stirred for 15 minutes. The pigment is filtered, dried and milled. Post-coating Example 3

Same as the Post-coating Example 2 but with sodium stearate instead of hydrogenated lecithin Post-coating Example 4 5 of the pigment of Example 4 are suspended in 10 ml of a 1% aqueous solution of carboxymethyl cellulose in water and stirred for 15 minutes at 60°C. The pigment is filtered, dried and milled. Post-coating Example 5

5 g of the pigment of Example 5 are stirred in 10 ml of a 1% solution sodium polyacrylate in water. The mixture is filtered, dried and milled. Then, 10 ml of an aqueous solution A1C1₃ 0.1M is dropped into the dispersion under stirred for 15 minutes. The pigment is filtered, dried and milled. Post-coating Example 6

5 g of pigment of Example 13 are suspended in 10 ml benzene containing 0.15 g of methyl hydrodienepolysiloxane and stirred for 5 minutes. The mixture is dried under vacuum untill solvent removal and the pigment is milled. Post-coating Example 7

5 g of pigment of Example 11 are suspended in 10 ml ethanol containing 0.1 g Fomblin HC/P2. The mixture is dried under vacuum untill solvent removal and milled.

Post-coating Example 8

2.5 g of the pigment of Post-coating Example 7 are suspended in 10 ml of a 1% aqueous solution of Al(NO)₃ and stirred for 15 minutes. The pigment is filtered, dried and milled. Post-coating Example 9 5 g of pigment of Example 10 are suspended in 10 ml benzene and 0.15 g of dimethylpolysiloxysilazane (n=30; Mw/Mn=1.15). The mixture is dried at 80° C to remove benzene completely and then heated at 115° C for 3 hours. Applicative Examples 1-3 - Lipsticks

100 g of lipstick contain:

Appl. Ex. 1 Appl. Ex. 2 Appl. Ex. 3

Castor oil 19.5 19.5 19.5

Isopropyl palmitate 1 1.6 1 1.6 1 1.6

Candelilla/carnauba waxes (2:1 w/w) 11.2 11.2 11.2

Stearin 7.9 7.9 7.9

Caprilic/capric triglyceride 15.0 15.0 15.0

Phytocoated pigment of Example 5 8.9 - 4.8

Phytocoated pigment of Example 6 - 8.9 5.1

White pigment TiO₂ (rutile) 4.6 4.6 4.6

Propylenglycol miristylether acetate 6.0 6.0 6.0

Glycerin 5.0 5.0 5.0

Demineralized water 5.0 5.0 5.0

Monoglycerides : soy lecithin (7:2 w/w) 4.5 4.5 4.5

Polybuthene 0.8 0.8 0.8

Applicative Examples 4-6 - Eye shadows

100 g of emulsions for eyelids contain:

Appl. Ex. 4 Appl. Ex. 5 Appl. Ex. 6

Carnauba wax i. i g 1 1 g i.i g

Partially hydrogenated soybean oil 1.9 g 1.9 g 1.9 g

Palm oil 1.9 1.9 1.9

Triethanolamine stearate 5.0 5.0 5.0

PEG- 1000 13.0 13.0 13.0

Talc (magnesium silicate) 0.7 0.7 0.7 Phytocoated pigment of Exam le 1 2.6 1.9 - Phytocoated pigment of Example 4 2.0 2.5 - Phytocoated pigment of Example 9 2.7 1.5 - Phytocoated pigment of Example 12 - 0.6 4.3 Phytocoated pigment of Example 2 - - 3.0 White pigment TiO₂ (rutile) 3.0 3.0 3.0 Sodium polymethacrylate 0.5 0.5 0.5 Preservatives 0.5 0.5 0.5 Demineralized water qb to 100 to 100 to 100 Applicative Examples 7-9 - Foundations

100 g of emulsions used as foundation contain:

Appl. Ex. 7 Appl. Ex. 8 Appl. Ex. 9

Triethanolamine stearate 2.5 2.5 2.5

Mono- and di-glycerol stearate 0.4 0.4 0.4 Talc (magnesium silicate) 1.9 1.9 1.9

Phytocoated pigment of Post-coating Example 2 3.7 - -

Phytocoated pigment of Post-coating Example 1 - 3.1 2.9

Phytocoated pigment of Post-coating Example 5 - 0.7 0.8

Phytocoated pigment of Post-coating Example 4 0.5 0.5 0.6 White pigment TiO₂ (rutile) 9.8 9.8 9.8

Micronized Nylon 9.0 9.0 9.0

Mix ofPEG-6 and PEG-32 9.0 9.0 9.0

Cyclomethycone 13.0 13.0 13.0

Propylenglycol 5.0 5.0 5.0 Glycerol 4.5 4.5 4.5

Demineralized water 25.6 25.6 31.6

Applicative Examples 10-12 - Pigments for edible use 100 g of a pigment for oral use contain:

Appl. Ex. 10 Appl. Ex. 11 Appl. Ex. 12

Titanium dioxide 48.5 48.5 48.5

Phytocoated pigment of Example 3 25.0 10.0 Phytocoated pigment of Example 5 25.0 - 50.0 Phytocoated pigment of Example 6 - 40.0 Citric acid 1.5 1.5 1.5

Each composition is then dispersed in aqueous solutions of sucrose 30% w/v. These dispersions exhibited high coloring and stability behaviours when utilized in the food manufacturing and excellent coating properties when used in the coating of tablets.

Claims

1. A coated pigment comprising: a) an inner core of a colored inorganic pigment; and b) an outer layer of at least one vegetal substance in the form of a complex with at least one lake-forming ion.

2. Coated pigment according to claim 1 wherein the inorganic pigment is selected in the group consisting in iron^ and/or iron ^m) oxides and hydrated oxides, clay colored with iron oxides, prussia blue, chrome^ oxide and hydrated oxide, and manganese^<π/ITI) phosphates.

3 Coated pigment according to claims 1 or 2 wherein the lake-forming ion is selected in the group consisting in aluminium, zinc, titanium, magnesium, calcium, strontium, barium, and mixture thereof.

4. Coated pigment according to claims 1 to 3 wherein the vegetal substance is one or more natural molecule with at least a carbonyl and an hydroxyl groups in vicinal or adjacent position, or its ketoenolic synthons.

5. Coated pigment according to claim 4 wherein the vegetal substance is selected in the group consisting in flavonoids, open ring polyphenols, benzoindenopyranones, quinones, chlorophyllins, vegetal melanins and mixture thereof.

6. Coated pigment according to claim 5 wherein the vegetal substance is a flavonoid selected in the group consisting in luteolin, armadendrin, morin, hesperetin, naringenin, quercetin, kaempferol, apigenin, rutin, chrysin, pelargonidin, cyanidin, delphinidin, delphinidin, petunidin, peonidin, malvidin, catechin, epicatechin, proanthocyanosides and gallocatechins.

7. Coated pigment according to claim 5 wherein the vegetal substance is a benzoindenopyranone selected in the group consisting in brazilein, brazilein, hematein, hematoxylin, santalin and santarubin.

8. Coated pigment according to claim 5 wherein the vegetal substance is an open ring polyphenol selected in the group consisting in gallic acid, tannic acid, protocatechuic acid, resveratrol, gallic acid, hydroxytyrosol, carthamin, curcumin and caffeic acid..

9. Coated pigment according to claim 5 wherein the vegetal substance is a quinone selected in the group consisting in rhein, aloin, aloe-emodin, alizarin, frangulin, crysofanol, cascarosides, morindon, hypericin, sennosides, lawsone, juglone, alkannin, shikonin and lapachols.

10. Coated pigment according to claims 6 to 9 wherein said vegetal substance is in the form of an O-glycoside or of a naturally occurring ester or ether thereof.

11. Coated pigment according to claim 6 wherein the vegetal substance is a chlorophyllin selected in the group consisting in Mg-chlorophyllin and Cu- chlorophyllin.

12. Coated pigment according to claim 6 wherein the vegetal substance is a natural melanin from plants or fungi or a synthetic derivative thereof.

13. Cosmetic composition comprising the coated pigment according to any of the claims 1 to 12.

14. Cosmetic composition according to claim 13, in the form of a free, poured or compacted powder, a fluid anhydrous greasy product, an oil for the body and/or the face, a lotion for the body and/or the face, or a hair product.

15. Cosmetic composition according to claims 13 or 14 which is a make-up composition.

16. Use of the coated pigments according to claims 1 to 12 wherein the inorganic pigment is an edible pigment, in the coloring of food and pharmaceutical compositions.

17. Process for the preparation of the coated pigments according to claims 1 to 12, which comprises suspending the inorganic colored pigment in a solution formed by alkaline salts of the vegetal substance and precipitating the coated pigment by mixing said suspension with a solution of at least one lake-forming ion.