FIELD OF THE INVENTION

The present invention relates to a hair colour formulation possessing the characteristic property of colouring/dyeing grey hair to black favouring reduced number of applications and application time comprising an effective amount of hair dyeing actives selected from anyone or more of naphthalene glycosides and indican in combination with a deglycosylating agent such as a beta glucosidase or acids and particularly, relates to hair colouring kit and hair colouring composition obtained thereof comprising the said actives in association with a cosmetically acceptable vehicle with or without other hair and skin benefiting agents. More particularly, the invention relates to simple and cost effective cosmetic compositions for topical use involving the said actives preferably sourced from a safe and renewable plant source Lawsonia inermis and Indigofera tinctoha which can be used singly or in combination with cosmetically acceptable vehicle/ carriers. Specifically a process for the preparation of the extract sourcing the said actives form the said natural sources is also provided which is convenient and safe to use in association to a hair dyeing method for colouring grey hair to black.

BACKGROUND ART

Hair dyeing method by using natural herbal raw materials (ex. Henna comprising lawsone as the active ingredient) can be traced back to atleast 4000 years. The hair of Egyptian mummies was found to be dyed with Henna. The natural hair dyes derived from flora and fauna are believed to be safe because of their non-toxic, non-carcinogenic and biodegradable nature. The current trend throughout the world is shifting towards the use of eco-friendly and biodegradable ingredients and the demand for natural dyes is increasing day by day (Bhuyan et al., Indian J Fibre & Textile Research, 2004, 29, 470).

Several methods for hair dyes were published in the literature. Lee S.H. in Korean patent application KR200070068881, 2007 discloses that hair dye composition using natural plant materials is provided to reduce side effects including skin irritation caused by chemical hair dye, improved hair affinity, hair conditioning and dye fastness. The said hair dye composition comprises powder, hot water extract or alcoholic extract of at least one natural plant material selected from Pinus denesiflora, Gingo biloba, Eucommia ulmoides, Acorus calamus, Japanese persimmon, Rubus coreanus, Lycium chinense, Epimedium koreanum and Artemisia princeps var. orientalis Shi, R. Z., in Chinese patent CN1923164, 2007 relates to a hair dye, especially a natural plant hair dye, that is obtained by mixture of two solutions: first solution is formed by agent and metal chelator, while the agent can be guar gum and polyquaternary ammonium salt or glycol cellulose, the chelator can be ferric or ferrous salts; the second solution containing extracts of pomegranate bark and logwood extracts and glycol cellulose.

Pushpangadan et. al., in WO 2006061847 Al, 2006 teaches a herb based black dye for hair from natural materials comprising the extracts of Juglans regia, Indigofera tinctoria, Terminalia chebula, Acacia sinuate, Lawsonia inermis, Trigonella foenum-graecum, Sapindus mukorossi, Eclipta alba, Emblica officianalis, Acacia catechu and Piper betel.

The dye is safe, non-toxic, anti-allergic, anti-dandruff and free from any toxic symptoms like itching.

The ready to use dye of the natural dye composition by Kirchmayr et al., WO 9618376 Al, 1996 was obtained by using two component system, component A comprising vegetable matter with soluble dyestuff content in a water-insoluble but at least partially water-permeable packet and component B comprising at least one thickener for aqueous media. The ready to use dye preparation thus obtained is applied to the hair and washed out after a period of setting.

Zhou, Z. S., in CN1989940 (A), 2007 discloses a fast plant based hair blacking agent wherein the agent consists of the mixture of two solutions. The first agent consists of adjuvant (nitrogen ketone) and metallochelates (soluble ferric salt or ferrous salt) and second agent contains gallnut extract wherein the said agent was added to isatis leaf extract and campeachy wood extract as coloring agent.

Yuqin, L, in CN101574316 (A), 2009 illustrates black hair colour may be prepared from pure natural black rice pigments, additives, solvent and water wherein the said colour is used for dyeing and blackening hair and has the characteristics of high material availability, simple extraction process, non-toxicity and safe use and is also beneficial for the environmental protection.

There are several henna based commercial products providing grey coverage that are available in the market today. Most of the products impart only characteristic henna color to the grey hair (various shades of orange to brown depending upon the base colour of the hair and number of applications) but is not of much help when black colouration of the hair is required. One product, KACA produced by the Chennai based company, UR's Herbal, Adayar provides for the black color of the hair. The product contains brown base and hair darkener powders wherein the said brown base has to be soaked in water after which it is applied to the hair and left for 2 hrs after which the hair is washed. The same process is repeated for three more times wherein the grey strands turn dark brown. Then, the second material, hair darkener is soaked in water and applied on the brown hair obtained in the preceding step and left for 45 minutes to obtain black coloured hair. The process of the said prior art is thus very cumbersome and time consuming involving multiplicity of process steps. .

Therefore the above existing state of the art does reveal several hair colouring agents including those derived form the natural materials enabling colouring gray hair to dark brown / black, the same in many instances is found to involve either the use of iron and some other metal chelators or include complicated process of application involving multiplicity of applications over prolonged time thereby making hair colouring a complex and cumbersome process. Thus there is a continuing need in the art to address effectively the art of colouring hair dark brown / black preferably involving formulations obtained of renewable natural sources which when applied on grey strands could turn it to dark brown / black in one to two applications thereby avoiding the tedious hair colouring process involving multiple applications to economize on both time and money.

OBJECTS OF THE INVENTION

It is thus the basic object of the present invention to provide for hair colour formulation which would be safe and compatible as a hair dyeing active to favour providing for coloring of grey hair to black /brown black color.

Yet another object of the present invention is directed to a process for the preparation of henna extract to facilitate grey hair coverage when used in association with other selective plant extract/ material for catering to the needs of variety of hair care conditions when the said hair care agents are used in an effective amount and acceptable form with or without other hair care/ skin care agents.

Yet another object of the present invention is to provide for hair care formulation possessing hair dyeing property that can be sourced simply and cost-effectively for variety of hair care formulations and the like either synthetically or from natural sources.

A further object of the present invention is directed to a process for the preparation of selective extracts and/or active ingredients from the leaves of the plant Lawsonia inermis Linn., and to a manner of extracting such selective actives as a hair benefiting agent especially favouring hair dyeing.

A further object of the present invention is directed to a process for the preparation of selective extracts and/or active ingredients from the leaves of Indigofera tinctoria Linn., and to manner of extracting such selective actives as hair benefiting agent especially favouring hair dyeing.

A still further object of the present invention is directed to provide for hair colouring composition/ kit using effective amounts of said extracts and/or active ingredients isolated selectively from the leaves of Lawsonia inermis Linn., and Indigofera tinctoria Linn., in combination with an enzyme selected from anyone or more of beta glucosidase or an acid such as hydrochloric acid such that the product obtained by incorporating the active ingredients/ extracts have good hair compatibility, deliver the desired color and convenient to apply and use.

SUMMARY OF THE INVENTION

According to the basic aspect of the present invention there is provided a hair colour formulation comprising (a) anyone or more of hair dyeing actives selected from (i) naphthalene glycosides of the general formula 1 as represented hereunder


Formula 1
and (ii) a hair dyeing active selected from indican of formula 2 as represented hereunder;
(b) a deglycosylating agent.

Advantageously, the said hair dyeing active colours favours colouring the hair from grey to dark brown/ black in one to two applications.

In another aspect of the present invention there is provided the said hair dyeing active selected from effective amounts of anyone or more of naphthalene glycosides of general formula 1 preferably comprises naphthalene monoglucoside of Formula 3 as represented hereunder

In another preferred aspect the said hair colour formulation comprising anyone or more of the naphthalene glycosides of Formula 1 preferably naphthalene monoglucoside of

Formula 3 as extracts/ concentrates from plant Lawsonia inermis, preferably in suitable organic solvents or mixtures of organic solvents such as methanol or ethanol.

In another preferred aspect of the present invention there is provided the said deglycosylating agent, an enzyme such as beta-glucosidase preferably sourced from dried leaf powder of Indigofera tinctoria.or anyone or more of an acid such as hydrochloric acid or acetic acid.

In accordance with another preferred aspect of the present invention there is provided the said hair colour active formulation comprising hair dyeing active indican of Formula 2 as extracts/ concentrates from the plant Indigofera tinctoria preferably in suitable organic solvents or mixtures of organic solvents such as methanol or ethanol.

In accordance with yet another preferred aspect of the present invention in the said hair colour formulation the said actives of Formula 1 and Formula 2 are synthesised or from selective plant extract extracted either as a single entity of anyone or more of the actives of Formula 1 or as a semi pure mixture of the compounds of Formula 1 or extracted as the single active of Formula 3 or Formula 2.

In our continued interest on the identification of new hair dyeing actives it has been surprisingly found that the abovesaid compounds meet the much desired requirement of being a superior hair dyeing active by way of colouring the hair from grey to black in only about two applications thereby reducing the number of applications required in case of the conventional natural hair colouring agent for colouring the hair to black. The application of the said actives for hair dyeing the hair is found to be simple affecting colour change from grey to black under minimum effective concentrations which is also cost-effective and safe in having less or no side effects in association to the said hair dyeing property.

Most importantly efforts were further directed for the provision of harnessing the said actives from extracts/ concentrates of natural renewable resource material such as plants.

It is important to clarify herein that the selective finding of the present invention resides in the identification of the selective extract from the plant Lawsonia inermis Linn in a particular solvent media sourcing the said actives of Formula 1 revealing hair dyeing characteristics thereby colouring the hair from grey to black in just about two applications either in the presence of selective extract/ concentrate of another plant material Indigofera tinctoria Linn sourcing compound of Formula 2 and a deglycosylating agent or in the presence of natural plant material Indigofera tinctoria Linn itself.

The said selective extract of the selective plants sourcing the said selective actives of Formula 1 and 2 is indeed surprising and is in significant deviation to the type of compounds and its end characteristic feature of attaining brown hair colour (black hair colour can only be attained after several applications) as obtained from the same said plant variety as discussed hereunder:

The plant, Lawsonia inermis Linn., commonly known as Henna is a shrub or small tree cultivated in India, Pakistan, Afghanistan and Iran. The powdered leaves of the plant are continuously in use as cosmetic staining of the hair, skin and nails. The plant is reported to contain carbohydrates, proteins, flavonoids, tannins and phenolic compounds, alkaloids, terpenoids, coumarins, xanthones and fatty acids. The plant has been reported to have analgesic, antiviral, hypoglycemic, hepatoprotective, immunostimulant, anti-inflammatory, anti-bacterial, anti-microbial, anti-fungal, anti-parsitic, antioxidant, antifertility, tuberculostatic, and anti-cancer properties (Int. J. Pharm. Sci. Drug Res., 2010, 2, 91-98). Two phenolic glucosides, lawsoniaside and lalioside and three known compounds, luteolin-7-glucoside, luteolin-3'-glucosidel,2-dihydroxy-4-glucosyloxy naphthalene, luteolin, p-sitosterol glucoside were reported from ethanolic extract of the dried leaves collected from Nigeria (Yoshio, T., J. Nat Prod., 1988, 51, 725-729). The biological activity of lawsone compound is also directed to its anti-bacterial, anti-spasmodic, corrosion inhibitory property. The said compound further encompasses the characteristic properties of dyeing as well as the UV absorption, wherein the dyeing property of henna leaves were further attributed to the presence of the same compound lawsone in henna leaves.

It has now been surprisingly found by way of the present invention that selective extract of Lawsonia inermis leaves extracted with methanol as solvent and active ingredients sourced therefrom involving actives of Formula 1 and preferably Formula 3 facilitate dyeing human hair from grey to dark brown in a single application and from grey to black in only about two applications when combined with other plant material Indigofera tinctoria Linn/ active compound of Formula 2 extracted therefrom in the total absence of lawsone known in the art as conventional hair colouring agent/ active sourced from Henna leaves or Lawsonia inermis Linn.

In another aspect of the present invention there is provided a process for the extraction of hair dyeing active of genera formula 1 and preferably naphthalene glucoside of Formula 3 from Lawsonia inermis comprising the steps of:

a) subjecting the air-dried leaves of Lawsonia inermis Linn., in powder form, to extraction with an organic solvent, preferably methanol to provide for an extract;

b) concentrating the extract in vacuo to provide a concentrate;

c) subjecting methanol residue to column chromatography, preferably a silica gel column using ethyl acetate: methanol (99:1), ethyl acetate: methanol (95:5) as eluents to provide another/ enriched concentrate;

d) subjecting the enriched concentrate for further separation by column using polyamide and sephadex LH-20 to get glycoside rich fractions;

e) pooling the fractions and concentrating the resulting solution to dryness in vacuo to provide another concentrate;

f) subjecting the enriched concentrate to a process of crystallization to provide forthe said hair dyeing active of Formula 1 or preferably naphthalene glucoside of Formula 3.

In yet another aspect of the present invention there is provided a process for the extraction of hair dyeing active indican of Formula 2 from Indigofera tinctoria comprising the steps of:

a) subjecting the air-dried leaves of Indigofera tinctoria in powder form, to extraction with an organic solvent, preferably methanol to provide for an extract;

b) concentrating the extract in vacuo to provide a concentrate;

c) subjecting methanol residue to column chromatography, preferably a silica gel column using ethyl acetate: methanol (99:1), ethyl acetate: methanol (95:5) as eluents to provide another / enriched concentrate;

d) subjecting the enriched concentrate for further separation by column using polyamide and sephadex LH-20 to get glycoside rich fractions;

e) pooling the fractions and concentrating the resulting solution to dryness in vacuo to provide another concentrate;

f) subjecting the enriched concentrate to a process of crystallization to provide for the said hair dyeing active of Formula 2.

More preferably, a hair colour active formulation is provided wherein the said hair dyeing active comprising selective extract of the plant Lawsonia inermis for purification comprises compounds of Formula 1 and preferably Formula 3 displaying substantially the following characteristics on thin layer chromatography using a pre-coated silica gel plate to provide a spot with Rf value of 0.46 in EtOAc: MeOH: water 100:13.5:10, absorbance value at 356 nm in UV(MeOH) spectrum; absorbance in the IR spectrum at 3410 (br), 1716 and 1707 cm"1 and the hexaacetate derivative of the glycoside showed the following characteristic signals in Proton NMR in CDCI3: 5 1.98 (3H,s), 2.01 (3H,s), 2.05 (3H,s), 2.16 (3H,s), 2.36 (3H,s), 2.45 (3H,s), 3.59 (lH,m), 3.89 (1H, dd, J = 12.4 & 1.8 Hz), 4.34 (1H, J=4.4 & 12.4 Hz), 5.08 (1H, d, J=8.1Hz), 5.21 (1H, t, J=9.3 Hz), 5.26 (1H, t, J=9.3Hz), 5.46 (1H, J=8.8 Hz), 7.12 (1H, s), 7.54 (2H, m), 7.85 (1H, d, J=9.0 Hz), 8.20 (1H, J=9.0 Hz). Carbon NMR in CDCI3 : 8 20.44, 20.44, 20. 52, 20, 64, 20.86, 20.86, 61.16, 67.84, 71.57, 72.05, 72.84, 101.6, 114.85, 121.36, 122.33, 125.7, 126.5, 127.12, 128.99, 139.0, 143.5, 168.6, 168.9, 169.06, 169.26, 170.2, 170.3.

In another aspect of the present invention there is provided a method of colouring grey hair employing the said hair colour formulation comprising the steps of

a. suspending anyone or more of hair dyeing actives selected from general Formula
1 and/ or Formula 2 in effective amount of water;

b. adding and stirring effective amounts of the deglycosylating agent preferably
sourced from dried leaf powder of Indigofera tinctoria in the solution of step (a);

c. applying the solution obtained from step (b) above on grey hair;

d. leaving the said applied solution on hair for about 1-2 hours;

e. washing the hair to obtain said coloured hair thereof.

In another aspect of the present invention there is provided hair colouring kit for topical use comprising

(a) anyone or more of hair dyeing actives selected from (i) naphthalene glycosides of the general formula 1 as represented hereunder

Formula 1
and (ii) a hair dyeing active selected from indican of formula 2 as represented hereunder;


(b) a deglycosylating agent;

(c) instructions for effective colouring of the hair employing the said components of
the kit.

Preferably, in the said hair colouring kit the said hair dyeing actives selected from (i) naphthalene glycosides of the general formula 1 is preferably naphthalene monoglucoside of Formula 3; and

wherein the said deglycosylating agent (b) an enzyme such as beta-glucosidase, is in the form of solid powder or solution and is preferably dried leaf powder of Indigofera tinctoria or anyone or more of an acid such as hydrochloric acid or acetic acid.

In still another aspect of the present invention there is provided hair colouring composition for topical use comprising

(a) anyone or more of hair dyeing actives selected from (i) naphthalene glycosides of the general formula 1 as represented hereunder


Formula 1
and (ii) a hair dyeing active selected from indican of formula 2 as represented hereunder;
Indican (Formula 2)

(b) a deglycosylating agent; and

(c) a cosmetically acceptable vehicle with or without other hair care benefiting
agents.

Preferably, in the said hair colouring composition the said hair dyeing active comprises about 0.1 wt% to about 99% wt. % of the said hair colouring actives, preferably 0.1 wt% to 60 wt% of the said hair colouring actives and more preferably and 0.1 wt% to 40 wt% of the said hair colouring actives as an active ingredient;and wherein said deglycosylating agent comprises preferably 0.001 to 5 wt% of the enzyme or preferably 0.1 to 10 wt% of hydrochloric acid.

More preferably, the said hair colouring composition is made available in the forms selected from a leave on or a wash-off product adapted for topical delivery in the form of creams, emulsions, gels, lotions, hair packs, wraps, films or patches as a vehicle for topical application of the said hair colour formulation.

DETAILED DESCRIPTION OF THE INVENTION
Thus as described hereinbefore, the present invention provides for a hair colour formulation comprising (a) anyone or more of hair dyeing actives selected from (i) naphthalene glycosides of the general formula 1 as represented hereunder

Formula 1
and (ii) a hair dyeing active selected from indican of formula 2 as represented hereunder;

(b) a deglycosylating agent.
Advantageously, the said hair dyeing active favours colouring the hair from grey to dark brown/ black in one to two applications.

In the said hair colour formulation the said hair dyeing active selected from effective amounts of anyone or more of naphthalene glycosides of general formula 1 preferably comprises naphthalene monoglucoside of Formula 3 as represented hereunder

In accordance with yet another aspect of the invention there is provided a process for the extraction of said actives from Lawsonia inermis comprising the steps of:

a. subjecting the air-dried leaves of Lawsonia inermis Linn., in powder form, to
extraction with an organic solvent, preferably methanol to provide for an extract;

b. concentrating the extract in vacuo to provide a concentrate;

c. subjecting methanol residue to column chromatography, preferably a silica gel
column using ethyl acetate: methanol (99:1), ethyl acetate: methanol (95:5) as
eluents to provide another / enriched concentrate;

d. subjecting the enriched concentrate for further separation by column using
polyamide and sephadex LH-20 to get the glycoside rich fractions;

e. pooling the fractions and concentrating the resulting solution to dryness in
vacuo to provide another concentrate;

f. subjecting the enriched concentrate to a process of crystallization to provide the
compounds of the invention.
In another aspect the present invention relates to a process of preparing the selective extract and/ or active ingredient derived from leaf extract of the plant Lawsonia inermis to be used in the composition of the present invention.

Yet another aspect of the present invention relates to the process for preparing the selective extract and/or active ingredients comprises their extraction from the leaf of Lawsonia inermis using appropriate solvent in above said sequence of process steps. The said isolation process may result in mixture of compounds having different and defined proportion or in an enriched extract high in specific compound/s or in a pure compound.

A further aspect of the present invention relates to a process for making and using the compositions for dyeing the hair which comprise an effective amount of the said ingredients preferably a selective extract of leaf and/ or active ingredient isolated from the leaves of Lawsonia inermis and Indigofera tinctoria together with cosmetically acceptable hair/ skin care vehicles.

The term "hair" as used herein includes naturally exposed to the environment and can be the scalp, mustache and eye lids.

The term "cosmetic composition" is intended to describe compositions for topical application by way of applying and spreading on to the surface of human hair, including leave-on and wash-off products.

The term "cosmetically acceptable" as used herein means that the compositions / compounds so described are suitable for prolonged contact with human hair without undue toxicity, allergic responses, incompatibility, instability etc.

The term "effective amount" as used herein means that an amount of the compositions / compounds so described is sufficient, to induce a positive / desirable benefit without causing any unacceptable /serious side effect.

The present invention provides for mixture of compounds as extract or pure compounds acting as hair dyeing active in a hair colouring composition for topical use and process for producing the said mixture or pure compounds by isolation from the leaves of Lawsonia inermis Linn., and Indigofera tinctoria Linn., and also provides for processes for producing and methods of application of the said compositions to achieve hair dyeing effect.

According to a preferred aspect of the invention the said hair colour active composition comprises:

a. about 0.1% to about 99% weight percent of a mixture of henna leaf extract
and indigo leaf extract and/or active ingredient;

b. a deglycosylating agent; and

c. a cosmetically acceptable vehicle with or without other hair care benefiting
agents.

The amount of the mixture of henna and indigo leaf extract/ concentrate and/or active ingredient is preferably in the range of about 0.1% to about 99%, more preferably about 0.1% to 60%, most preferably 0.1% to about 40% of the total amount of the cosmetic composition.

In accordance with yet another aspect of the invention there is provided a method of extraction of selective extracts from the leaf of henna and indigo of the plants. For the purposes of extraction of such selective actives suitable conventional extraction methods, such as maceration, remaceration, agitation maceration, digestion, fluidized-bed extraction, ultrasound extraction, countercurreuit extraction, cryogenic extraction, percolation, repercolation, evacolation, diacolation and solid-liquid extraction under continuous reflux which is carried out in a Soxhlet extractor can be carried out, each of which is known to the person skilled in the art and any of which can be used in principle, reference may be made by way of example to Hagers Handbuch der Pharmazeutischen Praxis (5.sup.th edition, Vol. 2, pp. 1026 1030, Springer Verlag, Berlin-Heidelberg-IMew York 1991).

Importantly, the selective starting materials for the extraction are fresh or dried leaf of the henna and indigo the plants, which are mechanically comminuted prior to extraction. Preferably, coarsely ground air-dried leaf of Lawsonia inermis and Indigofera tinctoria were subjected to extraction with one or more organic solvents like lower alcohols, preferably methanol to provide an extract.

In this connection, all comminution methods known to the person skilled in the art are suitable, mention being made by way of example to comminution using a device containing blades.

In accordance with a preferred aspect of the invention, after the extraction, the resulting crude extracts is optionally subjected to further customary steps, such as, for example, concentration, fractionation by partitioning between solvents, purification, including different types of chromatography, concentration and/or decoloration. If desired, the extracts prepared in this way can, for example, be subjected to selective removal of individual undesired ingredients. The extraction can be carried out to any desired degree of extraction, but is usually carried out exhaustively.

Importantly in accordance with yet further aspect of the invention the present invention encompasses the finding that the extraction conditions and also the yields of the end extracts are selectively chosen depending on the desired field of use, by way of evaluation of efficacy through deployment of appropriate precise screening of hair dyeing activity applicable to the benefit attributes in accordance with the present invention and hair care formulations incorporating the same.

In accordance with yet another preferred aspect of the invention, the selective extract was concentrated in vacuo to provide for a concentrate, wherein the concentrate was subjected to one or more separation techniques to thereby identify the actives of desired efficacy in accordance with the hair care formulation of the invention.

Preferably, according to another aspect of the invention a typical active substance of the invention, whether obtained from the leaf comprised a combination of compounds.

Specifically various components are included in the cosmetic hair care compositions of the present invention that are usually used for cosmetic compositions such as, an aqueous component, an oily component, a powder component, alcohols, esters, a surfactant, a moisturizer, an antioxidant, an ultraviolet ray absorbent, a thickener, a coloring material, perfume, an anti-oxidant, pH regulator, a chelating agent, and antiseptics, that can be blended, with these cosmetics.

The ingredients essentially employed in such a composition of this invention are surfactants, oil bodying agents, emulsifiers, fats and waxes, stabilizers, polymers, silicone compounds, deodorants and antimicrobial agents, film formers, swelling agents preservatives, thickeners / herbal extracts / concentrates / active ingredients, pH adjusting agents, perfumes oils, and water to qs.

The composition according to the invention can be used for the production of cosmetic and/or dermopharmaceutical preparations for topical use in the form of products, e.g. lotions, creams, gels, oils, sticks, sprays, packs, wraps, woven or non-woven wipes, films, patches, alcoholic and aqueous/ alcoholic solutions, emulsions, wax/fat compositions, as a vehicle of the said hair growth composition.

These preparations can also comprise further auxiliaries and additives, such as, surfactants, oily bodies, emulsifiers, pearlescent waxes, bodying agents, thickeners, superfatting agents, stabilizers, polymers, silicone compounds, fats, waxes, lecithins, phospholipids, biogenic active ingredients, deodorants, antiperspirants, film formers, swelling agents, hydrotropes, solubilizers, preservatives, perfume oils, dyes, pH regulating agents and the like.

Lawsonia inermis and Indigofera tinctorial The selective natural renewable source for the extract/ concentrates of the invention.

The extracts to be used according to the invention are obtained from the leaf a plant of the Lytheraceae family, specifically Lawsonia inermis and Indigofer tinctoria belongs to Fabaceae.

Extract/ concentrates

The dried leaf of the plant Lawsonia inermis and Indigofera tinctoria according to the present invention generally comprise, as active ingredients, classes of chemicals like aromatic compounds. The final product has a composition which varies depending on the staring material and on the method of extraction chosen.

The Solvent Extraction process:

The extract/concentrates used according to the invention as described above for the purpose of producing hair care formulation, are prepared by conventional methods of extraction of leaves of plants. Such suitable conventional extraction methods, may include maceration, remaceration, agitation maceration, digestion, fluidized-bed extraction, ultrasound extraction, countercurrent extraction, cryogenic extraction, percolation, repercolation, evacolation, diacolation and solid-liquid extraction under continuous reflux which is carried out in a Soxhlet extractor, each of which is known to the person skilled in the art and any of which can be used in principle, reference may be made by way of example to Hagers Handbuch der Pharmazeutischen Praxis (5.sup.th edition, Vol. 2, pp. 1026 1030, Springer Verlag, Berlin-Heidelberg-New York 1991).

Starting materials are fresh or dried leaves of the plants Lawsonia inermis and Indigofera tinctoria, which are used for extraction of active ingredients and can be mechanically comminuted prior to extraction. In this connection, all comminution methods known to the person skilled in the art are suitable, mention being made by way of example to comminution using a device containing blades.
Solvents:

Solvents used for carrying out the extractions are preferably organic solvents, water or mixtures of organic solvents and water, in particular low molecular weight alcohols with greater or lesser water contents (distilled or un-distilled), preferably aqueous, alcoholic solutions with greater or lesser water contents. However, preference is particularly given to the extraction with w methanol, ethanol, propanol, butanol and isomers thereof.

The extraction usually takes place at 20°C to 140 °C, preferably at 30 °C to 120 °C, in particular at the boiling temperature of the solvents or solvent mixtures. In one embodiment, the extraction is carried out under an inert gas atmosphere to avoid oxidation of the ingredients of the extract. The extraction times are adjusted by any person skilled in the art depending on the variable parameters for the extraction process such as starting material, the extraction method, the extraction temperature, the ratio of solvent to raw material, etc. After the extraction, the resulting crude extracts can optionally be subjected to further customary steps, such as, for example, concentration, fractionation by partitioning between solvents, purification, including different types of chromatography, concentration and/or decoloration. If desired, the extracts prepared in this way can, for example, be subjected to selective removal of individual undesired ingredients. The extraction can be carried out to any desired degree of extraction, but is usually carried out exhaustively.

Air-dried dried leaves of Lawsonia inermis and Indigofera tinctoria preferably, coarsely ground are subjected to extraction with one or more organic solvents like lower alcohols, preferably methanol to provide for an extract.

The present invention encompasses the finding that the extraction conditions and also the yields of the end extracts can be chosen depending on the desired field of use, through deployment of appropriate precise screening techniques like hair dye.

EXAMPLES:

Example 1 - Extraction of leaves of Lawsonia inermis Linn.

The air-dried leaves of L inermis Linn., (100 g) was powdered, extracted with methanol through soxhlet apparatus for about 8 hrs. The dilute extract was concentrated under reduced pressure to get 35.0 g of crude methanol concentrate. The crude methanolic extract was titurated with acetone to get 26 g of acetone insolubles.

Example 2 - Extraction of leaves of Indloofera tinctoria Linn.

The air-dried leaves of J. tinctoria Linn., (106 g) were powdered, extracted with methanol through soxhlet apparatus for about 8 hrs. The dilute extract was concentrated under reduced pressure to get 26 g of crude methanol concentrate. The crude methanolic extract was titurated with acetone to get 15.0 g of acetone insolubles.

Example 3 - Hair dyeing on grey hair with extracts and Plant material

In first application, 6.46g of acetone insoluble extract of L inermis was taken in China dish and suspended in 25ml of water. To this added 5.Og of leaf powder of J. tinctoria and stirred well for two minutes. Previously tied grey hair swatch (5.0g) was dipped in the dye bath and occasionally stirred the dye solution. After two hrs, the hair swatch was removed from the dye bath, washed with plenty of water and finally shampooed. The swatch was dried at room temp and observed that the grey swatch turned dark brown in color.

In second application, 2.72 g of acetone insoluble extract of L inermis was taken in China dish and suspended in 15 ml of water. To this added 3.0 g of leaf powder of J. tinctoria and stirred well for two minutes. The brown colored hair swatch obtained from first application was dipped in the dye bath and left for two hrs. After two hrs, the hair swatch was removed from dye bath, washed with plenty of water and finally shampooed. The hair swatch was dried at room temp and found that the grey swatch turned to natural black colour.

Example 4 - Hair dveina on arev hair with extracts

Taken 5.5g of leaf powder of I. tinctoria was soaked in 40 ml of water for 3 hrs, filtered and this filtered water was used immediately. This water is the source for natural p-glucosidase enzyme. Taken 3.23g of acetone insoluble extract of L. inermis and 0.46g of acetone insoluble extract of J. tinctoria was taken in China dish and suspended in 20 ml of previously prepared IT water. Previously tied grey hair swatch (0.5g) was dipped in the dye bath and occasionally stirred the dye solution. After one hr, the hair swatch was removed from the dye bath, washed with plenty of water and finally shampooed. The swatch was dried at room temp and observed that the grey swatch turns to dark brown color.

Example 5 - Hair dveina on qrev hair with pure compounds

a) Taken 94.5 mg of naphthalene monoglycoside and 28.5mg of indican, dissolved in 8 ml of water, added 0.9mg of pure p-glucosidase enzyme and stirred the mixture (dye solution). 0.5 g of hair swatch was dipped in the dye solution and left for 2 hrs. After two hrs, the hair swatch was removed from the dye solution, washed with plenty of water followed by shampoo wash. Dried the hair swatch at room temp and found that grey hair swatch turned to dark brown.

b.i) Taken 28.7 mg of indican, dissolved in 8 ml of water, added 0.6mg of pure p-glucosidase enzyme and stirred the mixture (dye solution). 0.5 g of hair swatch was dipped in the dye solution and left for 2 hrs. After two hrs, the hair swatch was removed from the dye solution, washed with plenty of water followed by shampoo wash. Dried the hair swatch at room temp and found that grey hair swatch turned blue in color.

ii) Taken 31.7 mg of naphthalene glycoside, dissolved in 8 ml of water, added 0.6mg of pure p-glucosidase enzyme and stirred the mixture (dye solution). 0.5 g of hair swatch blue in color (previously dyed with indican solution as mentioned in above example 5.bi) was dipped in dye solution and left for 2 hrs. After two hrs, the hair swatch was removed from the dye solution, washed with plenty of water followed by shampoo wash. Dried the hair swatch at room temp and found that blue hair swatch turned to black color without any intermediate color.

Thus the present invention provides for the much desired hair colour formulation comprising the said hair dyeing actives and hair colouring kit and hair colouring composition obtained thereof for topical use for hair colouration from grey to black and processes for extracting the same said active from natural renewable appropriate plant variety. More specifically, the present invention is directed to serve . the much desired need for hair care actives/ formulations which would serve as more efficacious, safe to apply with better consumer acceptance in requiring lesser application time for colouring the hair to brown or black.

We Claim:
1. Hair colour formulation comprising (a) anyone or more of hair dyeing actives selected from (i) naphthalene glycosides of the general formula 1 as represented hereunder

Formula 1
and (ii) a hair dyeing active selected from indican of formula 2 as represented hereunder;

Indican (Formula 2) (b) a deglycosylating agent.

2. Hair colour formulation as claimed in claim 1 wherein said hair dyeing active is selected from effective amounts of anyone or more of naphthalene glycosides of general formula 1 preferably comprises naphthalene monoglucoside of Formula 3 as represented hereunder

3. Hair colour formulation as claimed in anyone of claims 1 and 2 comprising anyone or more of the naphthalene glycosides of Formula 1 preferably naphthalene monoglucoside of Formula 3 as extracts/ concentrates from plant Lawsonia inermis, preferably in suitable organic solvents or mixtures of organic solvents such as methanol or ethanol.

4. Hair colour formulation as claimed in anyone of claims 1 to 3 wherein said deglycosylating agent is an enzyme such as beta-glucosidase preferably sourced from dried leaf powder of Indigofera tinctoria or anyone or more of an acid such as hydrochloric acid or acetic acid.

5. Hair colour formulation as claimed in claim 1 comprising hair dyeing active indican of Formula 2 as extracts/ concentrates from the plant Indigofera tinctoria preferably in suitable organic solvents or mixtures of organic solvents such as methanol or ethanol.

6. Hair colour formulation as claimed in anyone of claims 1-5 wherein the said actives of Formula 1 and Formula 2 are synthesised or from selective plant extract extracted either as a single entity of anyone or more of the actives of Formula 1 or as a semi pure mixture of the compounds of Formula 1 or extracted as the single active of Formula 3 or Formula 2.

7. A method of colouring grey hair employing the hair colour formulation as claimed in claims 1-6 comprising the steps of

a. suspending anyone or more of hair dyeing actives selected from general Formula 1 and /or Formula 2 in effective amount of water;

b. adding and stirring effective amounts of the deglycosylating agent preferably
sourced from dried leaf powder of Indigofera tinctoria in the solution of step (a);

c. applying the solution obtained from step (b) above on grey hair;

d. leaving the said applied solution on hair for about 1-2 hours;

e. washing the hair to obtain said coloured hair thereof.

8. Hair colouring kit for topical use comprising

(a) anyone or more of hair dyeing actives selected from (i) naphthalene glycosides of
the general formula 1 as represented hereunder

Formula 1
and (ii) a hair dyeing active selected from indican of formula 2 as represented hereunder;

(b) a deglycosylating agent;

(c) instructions for effective colouring of the hair employing the said components of
the kit.

9. Hair colouring kit as claimed in claim 8 wherein said hair dyeing actives selected
from (i) naphthalene glycosides of the general formula 1 is preferably naphthalene
monoglucoside of Formula 3; and

Formula 3
wherein the said deglycosylating agent (b) an enzyme, such as beta-glucosidase is in the form of solid powder or solution and is preferably sourced from dried leaf powder of Indigofera tinctoria or anyone or more of an acid such as hydrochloric acid or acetic acid..

10. Hair colouring composition for topical use comprising

(a) anyone or more of hair dyeing actives selected from (i) naphthalene glycosides of the general formula 1 as represented hereunder

Formula 1
and (ii) a hair dyeing active selected from indican of formula 2 as represented hereunder;


(b) a deglycosylating agent; and

(c) a cosmetically acceptable vehicle with or without other hair care benefiting
agents.

11. Hair colouring composition as claimed in claim 10 wherein

said hair dyeing active comprises about 0.1 wt% to about 99% wt. % of the said hair colouring actives, preferably 0.1 wt% to 60 wt% of the said hair colouring actives and more preferably and 0.1 wt% to 40 wt% of the said hair colouring actives as an active ingredient; and

wherein said deglycosylating agent comprises preferably 0.001 to 5 wt% of the enzyme or preferably 0.1 to 10 wt% of hydrochloric acid.

12. Hair colouring composition as claimed in claims 10-11 in the forms selected from
a leave on or a wash-off product adapted for topical delivery in the form of creams,
emulsions, gels, lotions, hair packs, wraps, films or patches as a vehicle for topical
application of the said hair colour formulation.

13. Hair colour formulation comprising (a) anyone or more of hair dyeing actives
selected from (I) actives of general Formula 1 and Formula 2 (b) a deglycosylating
agent, a cosmetic hair colouring kit and composition obtained thereof, a process for
pooling the said hair dyeing actives from natural source material, and a method of
colouring the hair using the said hair colouring formulation substantially as herein
described and illustrated with reference to the accompanying examples.