DESC:FIELD OF THE INVENTION
The present invention relates to hair darkening oil composition which is useful for darkening natural hair fibres and more particularly to a hair darkening oil composition comprising a polyphenol comprising composition and a metal salt comprising composition.

BACKGROUND OF THE INVENTION
The desire to alter the color of human hair is not a facet of modern times. Since the days of the Roman Empire the color of human hair has been routinely altered to accommodate the changes of fashion and style. However, the attainment of precise initial colors which are retained by the hair for a desirable period has remained a more elusive goal. The difficulties in the development of hair coloring compositions which can deliver precise long-lasting colors are in part due to the inherent structure of the hair itself and in part due to the necessary conditions of effective hair coloration processes.

There are several hair coloring methods. One is the so-called oxidative dye approach. This is based on the oxidation of a p- phenylenediamine or p-aminophenol by hydrogen peroxide, in the presence of various couplers. This has been in use for a very long time and is used to generate a wide range of shades that are both lighter and darker than natural hair color. Since the final colored molecules are quite large, these hair colors are resistant to removal by shampooing. Such permanent oxidative dyes are usually marketed as two component systems - one containing the dye precursors in an alkaline base, and the other is a solution of hydrogen peroxide.

The existing water-based compositions have many disadvantages such as high concentration of synthetic dyes. Hair darkening using said compositions is a two-step process. The high concentration of synthetic dyes allows only single use of the product. Further, development of an oil based, natural hair darkening formulation which is non-hazardous and has low concentration of dye is a huge challenge.

Thus, there is a need to develop an oil based, natural hair darkening formulation which is non-hazardous and has low concentration of dye. Surprisingly, the inventors have found that polyphenols can be incorporated in oil-based formulations. Most of the existing compositions are water-based compositions wherein the polyphenol interacts with metal salt to form a complex which imparts the desired color to the hair. Hair darkening using said water-based compositions is a two-step process. After use of said water-based compositions, the product is usually rinsed off. Since the product is rinsed off, high percentages of polyphenol and metal salt are used in such compositions to acquire the desired color. Therefore, the hair color imparted by the water-based compositions does not have a sustained effect. Thus, there is a need to develop an oil based natural hair darkening composition having sustained hair darkening effect. Furthermore, these aqueous compositions require alkaline treatment to hair in order to increase the substantively of the color developed. This has the damaging effect to the hairs and hence should not be done repeatedly i.e. daily, regularly. Hence there is a need of a solution which can be used daily in order to attain the desired darkness of hair color and maintain it for longtime without damaging the hair fiber.

It is well known in the art that polyphenol is very difficult to incorporate in the oil. Therefore, there is need to provide oil-based hair darkening composition that incorporates polyphenol and metal salt with ease.

OBJECTS OF THE INVENTION
One object of the present invention is to provide a composition which is useful for darkening natural hair fibers.

Still another objective of the present invention is to provide oil-based hair darkening compositions that incorporate polyphenol and metal salt with ease.

Still another objective of the present invention is to provide a hair darkening oil composition comprising a polyphenol comprising composition and a metal salt comprising composition.

Still another objective of the present invention is to provide a hair darkening oil composition comprising a polyphenol-metal complex in an oil phase.

Still another objective of the present invention is to provide a method of preparing hair darkening oil composition

Still another objective of the present invention is to provide a hair darkening oil composition that is beneficial in hair fall reduction due to breakage.

BRIEF DESCRIPTION OF DRAWINGS
The above and other features, aspects, and advantages of the subject matter will be better understood with regard to the following description and accompanying drawings where:
Fig. 1 shows the plot of ?L values obtained after 15 cycles and after 30 cycles of the hair darkening oil composition of present invention
Fig. 2 shows the plot of ?E values obtained after 15 cycles and after 30 cycles of the hair darkening oil composition of present invention.

SUMMARY OF THE INVENTION
In one aspect of the invention there is provided a hair darkening oil composition comprising:
a) a polyphenol comprising composition; and
b) a metal salt comprising composition
wherein the polyphenol comprising composition and the metal salt comprising composition are present in the ratio of 1:999 to 999:1.

In one aspect of the invention there is provided a hair darkening oil composition comprising a polyphenol-metal complex in an oil phase.

In one aspect of the invention there is provided a method of preparing hair darkening oil composition comprising mixing a polyphenol comprising composition with a metal salt comprising composition in the ratio 1:999 to 999:1 at a temperature in the range of 25-30oC to obtain the hair darkening oil composition.

In one aspect of the invention there is provided a hair darkening oil composition that reduces hair fall.

These and other features, aspects, and advantages of present subject matter will become better understood with reference to the following description. This summary is provided to introduce a selection of concepts in a simplified form. This summary is not intended to identify key features or essential features of the subject matter, nor is it intended to be used to limit the scope of the subject matter.

DESCRIPTION OF THE INVENTION
For convenience, the terms used herein have the meanings recognized and known to those of skill in the art, however, for convenience and completeness, particular terms and their meanings are set forth below.

The articles “a”, “an” and “the” are used to refer to one or to more than one (i.e., to at least one) of the grammatical object of the article. The terms “comprise” and “comprising” are used in the inclusive, open sense, meaning that additional elements may be included. It is not intended to be construed as “consists of only”. Throughout this specification, unless the context requires otherwise the word “comprise”, and variations such as “comprises” and “comprising”, will be understood to imply the inclusion of a stated element or step or group of element or steps but not the exclusion of any other element or step or group of element or steps.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. Although any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the disclosure, the preferred methods, and materials are now described. All publications mentioned herein are incorporated herein by reference.

The present invention relates to a hair darkening oil composition comprising:
a) a polyphenol comprising composition; and
b) a metal salt comprising composition
wherein the polyphenol comprising composition and the metal salt comprising composition are present in the ratio of 1:999 to 999:1.

The present invention also relates to a hair darkening oil composition comprising a polyphenol-metal complex in an oil phase.

In another embodiment of the invention, the polyphenol-metal complex is prepared by mixing a polyphenol comprising composition and a metal salt comprising composition in the ratio of 1:999 to 999:1.

In another embodiment of the invention, the polyphenol comprising composition comprises:
a) 0.01% to 99.9 % w/w of a vegetable oil and/or an emollient;
b) 0.0001 to 0.5 % w/w of a polyphenol; and
c) excipients.

In another embodiment of the invention, the metal salt comprising composition comprises:
a) 0.01% to 99.9 % w/w of a vegetable oil and/or an emollient;
b) 0.0001 to 50% of co-solvent;
c) 0.00001 to 0.5 % of a metal salt; and
d) excipients.

In another embodiment of the invention, the emollients are selected from the group consisting of but not limited to isopropyl myristate , isononyl nonanoate, isohexadecane, mineral oil, isoparaffin oils, emollient esters, silicone oils, dimethicone fluid, cyclomethicone, fish oil, low chain length alkanes, low chain length fatty acids, low chain length fatty alcohols, petroleum jelly, petroleum waxes, bees wax, carnauba wax, candelilla wax, microcrystalline wax, rice bran wax, shea butter, mango butter, almond butter, hydrogenated oils, hydrogenated fats and other all other types of anhydrous waxes, and fatty materials or combinations thereof.

In another embodiment of the invention, the vegetable oils are selected from the group consisting of coconut oil, sesame oil, rice bran oil, corn oil, canola oil, sunflower oil, safflower oil, soyabean oil, cotton seed oil, peanut oil, palm oil, palm kernel oil, coconut fatty acids, argan oil, and other exotic vegetable oils in crude or refined or partially refined, de-colourised form or combinations thereof.

In another embodiment of the invention, the polyphenols are selected from gallic acid and its esters such as methyl gallate, palmityl gallate, ethyl gallate, propyl gallate, butyl gallate, hexyl gallate, octyl gallate, lauryl gallate, behenyl gallate, tannic acid and its esters or combinations thereof.

In another embodiment of the invention, polyphenol is preferably gallic acid

In another embodiment of the invention, the metal salt is preferably an iron salt.

In another embodiment of the invention, the iron salts are selected from the group consisting of ferrous chloride, ferric chloride, ferrous stearate, ferrous palmitate, ferrous gluconate, and ferrous sulfate or combinations thereof.

In another embodiment of the invention, the co-solvents are selected from the group consisting of methanol, ethanol, propanol, isopropanol, butanol, pentyl alcohol, glycerin, propylene glycol, butylene glycol, pentylene glycol, hexylene glycol, octyldodecanol and other alcohols and glycols, and transcutol or combinations thereof. The co-solvent is present in the range of 0.0001 to 50%.

In another embodiment of the invention, the hair darkening composition is used for darkening natural hair fibers and prevention of fall of natural hair fiber of mammals which includes humans.

In another embodiment of the invention, the excipients are selected from the group consisting of buffering agents, antioxidants, cosmetic use oil anti microbials, colorant, fragrance, surfactants, biological actives, and solubilizers or combination thereof.

In another embodiment of the invention, the buffering agents like acids and alkalies and their salt are selected from group consisting of but not limiting to acetic acid, formic acid, propionic acid, hydrochloric acid, sulphuric acid, phosphoric acid, nitric acid, triethanolamine, aminopropanol, potassium hydroxide, sodium hydroxide etc. This may be utilized in the range of 0.00001 to 10% w/w.

In another embodiment of the invention, the antioxidants are selected from the group consisting of vitamin E and its derivatives, vitamin C and its derivatives, vitamin A and its derivatives, flavonoids, polyphenols, BHT, BHA, TBHQ, Tinoguard T and other grades of Tinoguard series etc. This may be utilized in the range of 0.0001 to 10% w/w.

In another embodiment of the invention, the cosmetic use oil anti microbials are selected from the group consisting of salicylic acid and its derivatives, para-amino benzoic acid and its derivatives such as methyl paraben, ethyl paraben, propyl paraben, butyl paraben etc. This may be utilized in the range of 0.0001 to 10% w/w.

In another embodiment of the invention, the colorant is selected from the group consisting of cosmetically and/or food grades approved dyes, natural pigments like curcumin, anthocyanin, lycopene, lutein and its derivatives etc. This may be utilized in the range of 0.0001 to 10% w/w.

In another embodiment of the invention, the fragrance is selected from the group consisting of synthetic or natural essential oils for fragrance purpose. This may be utilized in the range of 0.0001 to 10% w/w.

In another embodiment of the invention, the surfactants can be tween, span, anionic, nonionic or cationic surfactants. The surfactants can be Steareth-4, Laureth-4. This may be utilized in the range of 0.0001 to 10% w/w.

In another embodiment of the invention, the biological actives are selected from the group consisting of herbal extracts like glycyrrhiza extract, apegenin, coleus extract, henna extract, rosemary extract, marigold flower extract, forskolen or any other herbal, synthetic or hair and scalp benefit actives. This may be utilized in the range of 0.0001 to 10% w/w.

In another embodiment of the invention, it may contain co-solvents or solubilizers to solubilize the other excipient materials like biological actives, antioxidants etc. These co-solvents can be alcohols like methanol, ethyl alcohol, propyl alcohol, butyl alcohol etc., or specific group of co-solvents like transcutol, PEGs, glycols etc. This may be utilized in the range of 0.0001 to 30% w/w.

According to another embodiment, the composition is water free.

According to another embodiment, the composition has viscosity.

According to another embodiment, the composition has been studied for efficacy evaluation by change in the LAB value.

According to another embodiment, the composition has been studied for hair darkening effect on sensorial benefits on hair.

According to another embodiment, the composition has been studied for benefits of hair darkening in hair fall reduction.

According to another embodiment, the composition has been studied for stability studies.

According to another embodiment, the composition is used for darkening the hair by application to the scalp and hair shafts.

According to another embodiment, the composition is packed individually or partly or is divided. According to yet another embodiment, the divided composition can directly be used by the consumer by the way of mixing at the time of the application.

According to another embodiment, the two part-polyphenol comprising composition and metal salt comprising composition can be mixed in any ratio i.e. in the ratio of 1:999 to 999:1, preferably in the ratio of 1:99 to 99:1, more preferably in the ratio of 1:9 to 9:1 and most preferably in the range of 1:1 to obtain a hair darkening oil composition.

According to another embodiment, the hair shows progressive change with respect to darkening the hair colour.

According to another embodiment, the composition is exemplified as under:

Polyphenol comprising composition:
Vegetable oil or emollient: 0.1 to 99.9 %
Polyphenol: 0.0001 to 0.5%
Excipients: Q.s

Metal salt comprising composition:
Vegetable oil or emollient: 0.1 to 99.9%
Co-solvent: 0.0001 to 50%
Metal salt: 0.00001 to 0.5%
Excipient: Q.s.

According to another embodiment, the present invention provides a method of preparing hair darkening oil composition comprising mixing a polyphenol comprising composition with a metal salt comprising composition in the ratio 1:999 to 999:1 at a temperature in the range of 25-30oC to obtain the hair darkening oil composition.

According to another embodiment, the polyphenol is gallic acid.

According to another embodiment, the metal salt is an iron salt.

Examples: The present invention is more particularly described in the following examples, that are intended as illustrations only, since numerous modifications and variations within the scope of the present invention will be apparent to those skilled in the art. Unless otherwise noted, all parts, percentages and ratios reported in the following examples are on weight basis and all reagents used in the examples were obtained or are available from the chemical suppliers.

Example-1: Working Examples
The following examples illustrate the versatility of the present invention. The hair darkening oil composition of present invention is contemplated by each of the examples tabulated below:

Formulation range
Polyphenol comprising composition Metal salt comprising composition
Vegetable oil 0.1 to 99.9 % Oil 0.01 to 99.9%
Polyphenol 0.0001 to 0.5% Co-solvent 0.0001 to 50%
Excipients Q.s. Metal salt 0.00001 to 0.5%

excipient Q.s.

Example 1
Polyphenol comprising composition Metal salt comprising composition
Coconut Oil Q.s. to 100 coconut oil Q.s. to 100
Octyl gallate 0.5 Alcohol 50
Colorant 4.19 FeCl3 0.5
Fragrance 1 Colorant 3.921
TBHQ 0.05 Fragrance 1
TBHQ 0.05
acetic acid 0.1

Example 2
Polyphenol comprising composition Metal salt comprising composition
Coconut Oil Q.s. to 100 coconut oil Q.s. to 100
Octyl gallate 0.0001 Alcohol 0.5
Colorant 4.19 FeCl3 0.00001
Fragrance 1 Colorant 3.921
TBHQ 0.05 Fragrance 1
sesame oil 20 TBHQ 0.05
acetic acid 0.1

Example 3
Polyphenol comprising composition Metal salt comprising composition
Coconut Oil Q.s. to 100 Isopropyl myristate (emollient) Q.s. to 100
Octyl gallate 0.1 Alcohol 0.5
Colorant 0.3 FeCl3 0.15
Fragrance 1 Colorant 0.8
TBHQ 0.05 Fragrance 1
sesame oil 20 TBHQ 0.05
Isopropyl myristate (emollient) 20 acetic acid 0.1

Example 4
Polyphenol comprising composition Metal salt comprising composition
Coconut Oil Q.s. to 100 Isopropyl myristate (emollient) Q.s. to 100
propyl gallate 0.3 isopropanol 3
Colorant 0.3 FeCl3 0.3
Fragrance 1 Red CI 26100 (0.1% sol) 0.3
TBHQ 0.05 Yellow CI 47000 (0.01% sol) 0.2
sesame oil 20 Green CI 61665 (o.1% sol) 0.3
Isopropyl myristate (emollient) 20 Fragrance 1
alcohol 10 TBHQ 0.05
Herbal extract 0.1
Laureth - 4 4

Example 5
Polyphenol comprising composition Metal salt comprising composition
Mineral oil Q.s. to 100 Isopropyl myristate (emollient) Q.s. to 100
ethyl gallate 0.25 isopropanol 3
Colorant 0.3 FeCl3 0.3
Frag 1 Colorant 0.8
TBHQ 0.05 Fragrance 1
safflower oil 20 TBHQ 0.05
Isononyl nonanoate (emollient) 20 canola oil 20
Herbal extract 0.1

Example 6
Polyphenol comprising composition Metal salt comprising composition
Mineral oil Q.s. to 100 palm oil Q.s. to 100
Lauryl gallate 0.25 isopropanol 3
Colorant 0.3 FeCl3 0.2
Fragrance 1 Colorant 0.8
Isopropyl palmitate 20 Fragrance 1
Herbal extract 0.1 TBHQ 0.05
alcohol 4

Example 7
Polyphenol comprising composition Metal salt comprising composition
Mineral oil Q.s. to 100 palm oil Q.s. to 100
Lauryl gallate 0.25 methanol 10
Colorant 0.3 Fe2SO4 0.2
Fragrance 1 Colorant 0.8
TBHQ 0.05 Fragrance 1
sunflower oil 20 TBHQ 0.05
Isopropyl palmitate 20
Herbal extract 0.1

Example 8
Polyphenol comprising composition Metal salt comprising composition
Isoparaffin oil Q.s. to 100 palm oil Q.s. to 100
palmityl gallate 0.5 methanol 10
Colorant 0.46 Fe2SO4 0.3
Fragrance 1 Colorant 0.8
TBHQ 0.05 Fragrance 1
Rice bran oil 20 TBHQ 0.05
Isononyl nonanoate (emollient) 20
Herbal extract 0.1
steareth - 4 (surfactant) 4

Example 9
Polyphenol comprising composition Metal salt comprising composition
Isoparaffin oil Q.s. to 100 corn oil Q.s. to 100
palmityl gallate 0.5 methanol 10
Colorant 0.46 Fe2SO4 0.3
Fragrance 1 Colorant 0.8
TBHQ 0.05 Fragrance 1
corn oil 20 TBHQ 0.05
isohexadecane (emollient) 20
Herbal extract 0.1
Propyl paraben 0.1
salicylic acid 0.2
argan oil 0.5

Example 10
Polyphenol comprising composition Metal salt comprising composition
Isoparaffin oil Q.s. to 100 corn oil Q.s. to 100
Behenyl gallate 0.5 methanol 10
Colorant 0.46 Fe2SO4 0.3
Fragrance 1 Colorant 0.8
TBHQ 0.05 Fragrance 1
corn oil 20 TBHQ 0.05
Isohexadecane (emollient) 20
Herbal extract 0.1
Propyl paraben 0.1
vitamin E acetate 0.2
ascorbyl palmitate 0.1
Colorant 0.05

Example 11
Polyphenol comprising composition Metal salt comprising composition
Laureth -4 (surfactant) 3.5 Ethyl alcohol 2.15
ethyl alcohol 3.5 IPM (Isopropyl myristate) (emollient) q.s. to 100
Apegenin (Herbal extract) 0.05 Cyclomethicone (SF1202) 22
salicylic acid 0.5 FeCl3 (Alc) Stock sol 2% 2.9
Vit E acetate 0.35 Hydrochloric acid 0.03
Ayurvedic oil extract 22 Colorant 3.921
Hydrolysed PCNO-Safflower oil 18 Fragrance 1
Refined sesame oil 25.08 TBHQ 0.05
refined rice bran oil Q.s. to 100 100
Octyl gallate 0.099
Colorant 4.19
Fragrance 1
TBHQ 0.05
100

Example 12

Polyphenol comprising composition Metal salt comprising composition
Isoparaffin oil Q.s. to 100 corn oil Q.s. to 100
gallic acid 0.01 methanol 10
Colorant 0.46 Fe2SO4 0.3
Fragrance 1 Colorant 0.8
TBHQ 0.05 Fragrance 1
corn oil 20 TBHQ 0.05
isohexadecane (emollient) 20
Herbal extract 0.1
Propyl paraben 0.1
salicylic acid 0.2
argan oil 0.5

Example-2: Efficacy studies of hair darkening oil composition of present invention

Objective: To evaluate hair darkening benefits of hair darkening oil composition

Methodology: This study was conducted on 100% white hair swatches and hair darkening benefits were compared against control (untreated) hair using chromameter. It is a precise tool to measure surface colour of hair. In the evaluation of hair darkening, combination of the L*, a* and b* values were studied. L* value provide objective and repeatable measure of hair darkening. ?E is calculated to measure overall effect of hair darkening. Negative b* value presents higher blue colour hence it can be studied to evaluate overall darkening effect on hair.

The reference hair darkening oil composition of present invention used for this study is Example 11.

For treated hair tress:
1. About 2 gm of 100% white hair with length of about 10cm was weighed.
2. The hair tress was washed with 0.2 ml of commercially available shampoo.
3. The hair strands were then dried with hair dryer (cool air dry).
4. Initial L*a*b* value for hair swatch was measured using chromameter.
5. 0.1 ml of polyphenol comprising composition and 0.1 ml of metal salt comprising of hair darkening oil composition of present invention was mixed and applied on hair swatches thoroughly.
6. Hair swatches were kept for 8 hours and washed with 0.2 ml of commercially available shampoo and cold dried.
7. This cycle from step 5 to 6 was repeated for 15 times and 30 times.
8. L*a*b* values were measured after 15th cycle and 30th Cycle.

For control hair tress:
1. About 2gm of 100% white hair with length of about 10cm was weighed.
2. The hair tress was washed with 0.2ml of commercially available shampoo.
3. The hair strands were then dried with hair dryer (cool air dry).
4. Initial L*a*b* value for hair swatch was measured using chromameter.
5. 0.1 ml of polyphenol comprising composition and 0.1 ml of metal salt comprising composition of placebo was mixed and applied on hair swatches thoroughly.
6. Hair swatches were kept for 8hours and washed with 0.2ml of commercially available shampoo and cold dried.
7. This cycle from step 5 to 6 was repeated 15 times and 30 times.
8. L*a*b* values were measured after 15th cycle and 30th Cycle.

Results obtained after completion of 15 cycles and 30 cycles of the hair darkening composition of present invention are provided below:

Observation and Results:
Product ?E ?L ?a ?b
Placebo (without active) 1.54 0.07 0.17 0.18
Treatment (15th cycles) 8.39 -3.13 -0.88 -7.73
Treatment (30th cycles) 16.13 -11.37 -1.42 -11.27

Conclusion:
There is significant difference in ?E and ?L values of placebo and treatment group which concludes that there are significant colour changes with hair darkening oil against placebo. It is clear from the above table that from the 15th cycle the promising results can be seen.

Example-3: Hair darkening effect on sensorial benefits on hair
Objective: To analyze the effect of two test prototype with hair darkening effect on sensorial benefits on hair

Protocol:
1. Three hair swatches (each weighing 5 g) with similar baseline sensory were prepared from a single bunch of hair
2. Amount of product applied= 0.5g. (10% of the weight of the hair swatch).
3. Product applied on damp hair and left for overnight to get dried oh hair.
4. Washed with 0.5g of 15% SLES solution. (10% of the weight of the hair swatch).
5. Repeat steps 2 to 4 for 15 times
6. Sensory analysis done by trained panelists on 10 people.
Observation:
The average values of control group (treated with SLES wash only), hair darkening water-based formulation and hair darkening oil composition of present invention have been tabulated in the below table:

Detangling Softness Smoothness Shine Manageability Limp Applied feel Overall
Control 3.47 3.56 3.38 2.94 2.88 0.00 0.34 3.28
Hair darkening water-based formula 3.34 3.31 3.03 2.94 3.13 0.00 0.25 3.03
Hair darkening oil- based formula 3.78 3.94 3.88 3.44 3.41 0.00 0.41 3.91

Conclusion: The hair darkening oil composition of present invention is significantly effective and distinctively different in terms of sensorial performance when compared against water-based hair darkening formulation. Even the slight change in the sensory value of 0.5 makes a significant difference. While on repeated usage water-based formulation was found to be making hair slightly less conditioned. Hence looking at this observation, hair darkening oil composition of present invention is most suitable formulation for progressive hair darkening application.

Example 4: Benefit of hair darkening formulation in hair fall reduction
Objective:
To evaluate the benefit of hair darkening formulation in hair fall reduction due to breakage, in terms of % hair fall reduction.

Methodology:
The study was conducted on hair swatch and the benefits of the hair darkening formulation of present invention were compared with that of the control (untreated) hair. Reduction in hair fall due to breakage with the hair darkening formulation of present invention is compared with that of control (untreated) hair.

For untreated hair tress:
1. About 5 g hair with length of about 20cm was weighed.
2. The hair strands were washed with 0.5 ml 15% SLES solution.
3. The hair tress was rinsed under running tap.
4. The hair strands were then dried with hair dryer (cool air dry).
5. It was combed 40 times from top to bottom (20 from front side & 20 from back side).
6. No. of hair fall due to breakage was collected and manually counted.
7. The experiment was repeated for a total no. of 6 hair tresses.

For treated hair tress (same protocol for both groups water-based and hair darkening oil composition of present invention
1. About 5 g hair with length of about 20cm was weighed.
2. The hair strands were washed with 0.5 ml 15% SLES solution.
3. The hair tress was rinsed under running tap.
4. On towel dried damp hair, 0.5g of the product is applied.
5. The hair strands were then dried with hair dryer (cool air dry).
6. The hair tress was then combed 40 times from top to bottom (20 from front side & 20 from back side).
7. No. of hair fall due to breakage was collected and manually counted.
8. The experiment was repeated for a total no. of 6 hair tresses.

Observations and results:
Hair tress No. No. of fallen Hair
(Untreated Hair) No. of fallen Hair
(Treated tress with hair darkening oil composition of present invention) No. Fallen hair (Treated with water-based product)
1 30 11 69
2 67 20 81
3 58 14 58
4 75 12 75
5 68 10 79
6 65 13 49
Average 60.5 13.3 68.5

Conclusion:
There is a significant reduction in hair fall due to breakage with application of the hair darkening oil composition of present invention when compared against untreated and water-based treated group. The hair fall reduction is up to 4.55x when compared against untreated group, while it is approx. 5.15x vs water-based treated group. This suggest that hair darkening oil composition of present invention has better hair strengthening effects compared to water-based product.

Example 5: Accelerated Stability Data:
The following stability data was obtained for polyphenol comprising composition and metal salt comprising composition. At room temperature (RT) the polyphenol comprising composition appears as a dark brown coloured oil free from any suspended particles. At room temperature (RT) the metal salt comprising composition appears as light yellow coloured clear oil free from any suspended particles. The appearance, fragrance and alcohol content were noted for both compositions over 1-4 months and at 38oC, 45oC and 55oC.

Polyphenol comprising composition

Month Condition Appearance Fragrance
Initial RT Dark brown coloured oil free from any suspended particles Characteristic fragrance
4 RT Complies Complies
Ref
38
45

Metal salt comprising composition

Month Condition Appearance Alcohol content Iron Content
Initial RT Light yellow coloured clear oil free from any suspended particles. Max 10% w/w 0.03%
4 RT Complies Complies Complies
Ref
38
45

Conclusion: Form the above tables, it is clear that the both polyphenol comprising composition and metal salt comprising compositions are stable.

The hair darkening oil composition of present invention is not limited to the embodiments discussed herein and can be embodied by various modifications within the scope of the following claims. It should be recognized that the preferred embodiments described above are exemplary only. Certain modifications and improvements will occur to the person skilled in the art upon a reading of forgoing description. It should be understood that all such modifications and improvements have been deleted herein for the sake of conciseness and readability but are properly within the scope of the following claims.
,CLAIMS:We claim:

1. A hair darkening oil composition comprising:
a) a polyphenol comprising composition; and
b) a metal salt comprising composition
wherein the polyphenol comprising composition and the metal salt comprising composition are present in the ratio of 1:999 to 999:1

2. A hair darkening oil composition comprising a polyphenol-metal complex in an oil phase.

3. A hair darkening oil composition as claimed in claim 2, wherein the polyphenol-metal complex is prepared by mixing the polyphenol comprising composition and the metal salt comprising composition in the ratio of 1:999 to 999:1

4. The composition as claimed in preceding claims, wherein the polyphenol comprising composition comprises:
a) 0.01% to 99.9 % w/w of vegetable oil and/or emollient;
b) 0.0001 to 0.5 % w/w of a polyphenol; and
c) excipients

5. The composition as claimed in preceding claims, wherein the metal salt comprising composition comprises:
a) 0.01% to 99.9 % w/w of a vegetable oil and/or emollient;
b) 0.0001 to 50% of a co-solvent;
c) 0.00001 to 0.5 % of a metal salt; and
d) excipients

6. The composition as claimed in preceding claims, wherein the emollients are selected from the group consisting of mineral oil, isoparaffin oils, emollient esters, silicone oils, dimethicone fluid, cyclomethicone, fish oil, low chain length alkanes, low chain length fatty acids, low chain length fatty alcohols, petroleum jelly, petroleum waxes, bees wax, carnauba wax, candelilla wax, microcrystalline wax, rice bran wax, shea butter, mango butter, almond butter, hydrogenated oils, hydrogenated fats, anhydrous waxes and fatty materials or combinations thereof.

7. The composition as claimed in preceding claims, wherein the vegetable oils are selected from the group consisting of coconut oil, sesame oil, rice bran oil, corn oil, canola oil, sunflower oil, safflower oil, soyabean oil, cotton seed oil, peanut oil, palm oil, palm kernel oil, coconut fatty acids, argan oil, and exotic vegetable oils or combinations thereof.

8. The composition as claimed in preceding claims, wherein the polyphenols are selected from gallic acid and its esters.

9. The composition as claimed in preceding claims, wherein the gallic acid and its esters are selected from the group consisting of methyl gallate, palmityl gallate, ethyl gallate, propyl gallate, butyl gallate, hexyl gallate, octyl gallate, lauryl gallate, behenyl gallate, tannic acid and its esters or combinations thereof.

10. The composition as claimed in preceding claims, wherein the polyphenol is a gallic acid.

11. The composition as claimed in preceding claims, wherein the metal salt is an iron salt.

12. The composition as claimed in preceding claims, wherein the iron salts are selected from the group consisting of ferrous chloride, ferric chloride, ferrous stearate, ferrous palmitate, ferrous gluconate, and ferrous sulfate or combinations thereof.

13. The composition as claimed in preceding claims, wherein the co-solvents are selected from the group consisting of methanol, ethanol, propanol, isopropanol, butanol, pentyl alcohol, glycerin, propylene glycol, butylene glycol, pentylene glycol, hexylene glycol, octyldodecanol, glycols, and transcutol or combinations thereof.

14. The composition as claimed in preceding claims, wherein the excipients are selected from the group consisting of buffering agents, antioxidants, cosmetic use oil anti microbials, colorant, fragrance, surfactants, biological actives and solubilizers or combinations thereof.

15. A method of preparing hair darkening oil composition comprising mixing a polyphenol comprising composition with a metal salt comprising composition in the ratio 1:999 to 999:1 at a temperature in the range of 25-30oC to obtain the hair darkening oil composition.

16. The method as claimed in claim 15, wherein the polyphenol is gallic acid.

17. The method as claimed in claim 15, wherein the metal salt is an iron salt.