Oxidative Red Hair Dye

This invention relates to a dye composition for dyeing keratinous fiber red. More specifically the composition is essentially free of o-, m- or p-phenylenediamine, 2,4-diaminoanisole and nitro compounds. Even more specifically the invention relates to a composition consisting of .alpha.-hydroxynaphthylene, p-aminophenol, a suitable modifier, a suitable coupler and a sufficient amount of a suitable base. When this composition is mixed with a suitable oxidizing agent and applied to keratinous fiber, particularly human hair, the fiber is dyed red.

It is generally known that commercial oxidative hair dyes require the presence of o-, m- or p-phenylenediamine or 2,4-diaminoanisole, and the direct dyes require the presence of nitro compounds. However, in recent years it has been found that, o-, m- and p-phenylenediamine, 2,4-diaminoanisole and nitro compounds may exhibit a mutagenic reaction in the Ames test, either when oxidized or unoxidized. See Ames, et al., "Hair Dyes Are Mutagenic: Identification of a Variety of Mutagenic Ingredients," PROC. NAT. ACAD. SCI. U.S.A., 72, No. 6, pp. 2423-2427, June, 1975.

While the compounds used in this invention have been known for many years, these compounds have been used in association with o-, m- or p-phenylenediamine or 2,4-diaminoanisole but have never been employed by themselves because it was thought that the one of the latter compounds was necessary to form the desired shades of red in oxidative hair dyes. For discussion of the role of o-, m- and p-phenylenediamine and 2,4-diaminoanisole as dye-forming intermediates in oxidation dyes see The Chemistry and Manufacture of Cosmetics, Vol. IV, 2nd Edition, edited by Maison G. de Navarre, pages 841-920.

It has now been discovered that a specific unique combination of previously known compounds has been found to give excellent dyes for dyeing keratinous fibers red without using any o-, m- or p-phenylenediamine, 2,4-diaminoagrisole or nitro compounds.

One aspect of this invention is a composition for dyeing keratinous fiber red. The composition is essentially free of o-, m- or p-phenylenediamine, 2,4-diaminoanisole and nitro compounds. The composition consists essentially of

ABOUT 0.5 TO 3.5 PARTS BY WEIGHT P-AMINOPHENOL,

ABOUT 0.2 TO 1.5 PARTS BY WEIGHT .alpha.-HYDROXYNAPHTHALENE,

ABOUT 0.0 TO 10.0 PARTS BY WEIGHT OF A SUITABLE MODIFIER,

ABOUT 0.0 TO 5.0 PARTS BY WEIGHT OF A SUITABLE COUPLER, AND

A SUFFICIENT AMOUNT OF A SUITABLE BASE TO MAKE UP A TOTAL OF 100 PARTS BY WEIGHT OF SUCH COMPOSITION.

Another aspect of the invention is a combination of the above composition with a suitable oxidizing agent. This combination may be an actual mixture of the two or may be a combination of the composition and the oxidizing agent in two separate containers together in a single package.

Still another aspect of the invention is a process for dyeing keratinous fibers, particularly human hair, red, which process comprises contacting the fibers with an effective amount of a mixture of the composition and an oxidizing agent for a time sufficient to effect dyeing of the fibers.

The following table gives the operable ranges in parts by weight (pbw) for each of the components of the novel composition of the invention as well as the optimum ranges for each of the components.

The two essential compounds in the composition of this invention are:

(I) .alpha.-hydroxynapthalene and (II) p-aminophenol as represented by the following formulas: ##STR1## Each compound may be readily prepared by means known in the art or are available through chemical outlets such as Aldrich Chemical Co., Inc.

The dye base or carrier, which is used in the composition of this invention can be any suitable, compatible base which is generally known in the art, and will contain several components which may include a fatty acid in the form of soap, synthetic detergents, a gelling or thickening agent, a solvent, a leveling agent, a hair conditioning agent and other additives such as anti-oxidants, oxidation, retarders, chelating agents, pH adjusters and a perfume. In many cases, the component which would fall into one category also falls into another category. Thus a fatty acid used in a base which uses ammonia as the pH adjuster may appear as ammonium oleate and thus act as a surfactant. Representative bases may be prepared employing the principles set forth in The Chemistry and Manufacture of Cosmetics, ibid.

Suitable fatty acids include oleic acids, palmitic acid, stearic acid, lauric acid and coconut fatty acids. Normally these are used as the ammonium salt. These generally are good solvents and aid in dispersion of the dye intermediates and other ingredients in the product.

The surfactants used in the base may be non-ionic, anionic, amphoteric or combinations thereof. The surfactants serve as penetrants, dye dispersing agents, coupling agents, foam and cleansing agents (in shampoo--in colors) and they are often an essential part of the gelation system. Surfactants may include higher alcohol sulfates, ethoxylated nonylphenols, ethoxylated fatty esters, amphoterics, and the like. Particularly valuable is polyethylene glycol p-nonylphenol ether having four ethylene glycol units (IGEPAL.RTM. CO-430), polyethylene glycol(3) lauryl amide (Amidox L.sub.2) and ammonium lauryl sulfate (Carsonol ALS).

Gelling agents can be employed if a gel is desired for the base. In this case a fatty alcohol such as oleyl alcohol can be employed. Ethoxylated fatty alcohol may also be used along with alkylol amides. Gelling agents serve as thickeners solubilizers and foam stabilizers. Oleyl alcohol has been found to be particularly valuable.

Solvents are employed in the base both to solubilize the dye intermediates as well as the water immisible components in the dye base. The preferred solvents are the lower alcohols, glycols, and glycol ethers. For example, ethanol, propylene glycol, isopropyl alcohol and glycerine. Glycerine also acts as a humectant. Isopropanol, propylene glycol, and glycerine are preferred.

Leveling agents as such are seldom included in the dye base composition because may of the other ingredients perform this function, for example many of the solvents are useful as leveling agents. Fatty alcohols, fatty esters, alkylol amides and glycols all act to slow down the fusion of the intermediates into the hair and level absorbtion of the colors.

Many of the ingredients already mentioned also serve as hair conditioning agents. Other ingredients that can be used specifically for this purpose not mentioned hereinbefore include lanolin derivatives, proteins and polyvinylpyrrolidone.

Antioxidants are often added to the base to prevent air oxidation and the resulting deterioration of the product. Generally the most widely used antioxidants are the alkali metal sulfites, BHA or BHT, specifically sodium sulfite. The amount of the antioxidant used is sufficient to protect the product during the manufacture and to take care of oxygen in the head space of the bottle. Generally this amount is less than 1% and usually is not more than 0.5%. Other antioxidants include certain mercaptans (such as thioglycolic acid) ascorbic acid and 2,3-dihydroxynaphthylene.

In addition to the antioxidant, other components may be added as oxidation retarders. If oxidation takes place too rapidly before adequate diffusion of the dye intermediates into the hair can take place, weaker and uneven dyeing may result. Thus, additives are included which slow down the oxidation somewhat so that the color is developed only after the dye is sufficiently diffused into the hair. Antioxidants will act as retarders in certain instances, but specific retarders may be included such as polyhydroxyphenols, 1-phenyl-3-methyl-5-pyrazolone and the like.

Also included in the base may be chelating agents which are used to tie up trace quantities of heavy metals which can catalyze the decomposition of the perioxide once the peroxide is mixed with the dye. Generally the most useful chelating agents are the di-, tri- or tetra-sodium salts of ethylenediaminetetraacetic acid (EDTA).

The dye base and final dye composition is preferably quite alkaline having a pH of 9.0 to about 10.5. The high alkalinity is necessary because oxidation occurs more readily in an alkaline system and at alkaline pH's, the hair softens and swells making it more receptive to the dye. The most commonly used alkali is ammonium hydroxide. Not only is it a good pH adjuster but it also is an effective swelling agent. Other additives such as alkylol amines can be used in addition to or in place of ammonia.

Finally, if desired a perfume can be added. A suitable perfume should be unaffected by the alkaline product and should be relatively unaffected by the peroxide during the short period of time that the dye bath is applied to the hair. Perfume compounds should be free of aldehydes which may react with amino compounds and cause difficulty.

In preparing the base composition, the ingredients (save for the pH adjuster and the perfume) are placed together in a suitable mixing vessel, heater to the necessary temperature generally about 50.degree. to 175.degree. Farenheit, and stirred for about 20 to 60 minutes, generally about 30 minutes being sufficient. The base is then ready for the other components of the composition to be added thereto.

In addition to the base composition as well as the two essential ingredients to obtain the red dye, other ingredients also included in the composition are modifiers and couplers. Modifiers and couplers are optionally added to produce desirable color modifications as well as to serve as color stabilizers, antioxidants and retarders.

For purposes of this invention, modifiers are secondary dye intermediates which are hydroxylated aryl compounds and include such compounds as pyrocatechol (1,2-benzenediol), resorcinol (1,3-benzenediol), chlororesorcinol, hydroquinone (1,4-benzenediol), pyrogallol (1,2,3-benzenetriol), phloroglucinol (1,3,5-benzenetriol), 1,3-dihydroxynaphthalene, 1,7-dihydroxynaphthalene and 2,7-dihydroxynaphthalene and glycin (N-(p-hydroxyphenyl)- glycine). Of these modifiers those particularly valuable in this instance are glycin, phluroglucinol and pyrocatechol. For bright red shades no modifier is needed. Generally, if the modifier is be present, it is present in an amount of about 0.2 10.0 pbw and preferably 0.5 to about 5.5 pbw in the total composition. A particularly valuable combination (in 100 parts of total composition) contains

0.1 to 1.5 parts by weight of glycin,

0.2 to 2.0 parts by weight of phluroglucinol, and

0.0 to 2.0 parts by weight of pyrocatechol.

Suitable couplers include primary dye intermediates such as aryl substituted o- and p-diaminobenzenes and o- and p-aminophenols and suitable acid addition salts thereof such as the hydrochlorides and sulfates as well as secondary dye intermediates such as m-aminophenols and suitable acid addition salts thereof. Generally the coupler is present at about 0.0 to 5.0 and preferably 0.3 to 3.0 pbw. Particularly valuable are m-aminophenol, p-methylaminophenol sulfate, o-aminophenol, p-aminodiphenylamine sulfate, and the like. Three preferred couplers include

m-aminophenol (0.0-1.0 parts by weight),

p-methylaminophenol sulfate (0.0 to 1.0 parts by weight), and

p-aminodiphenylamine sulfate (0.0 to 1.0 parts by weight).

The composition of the invention is prepared by mixing the base as prepared as discussed hereinbefore with the essential ingredients and the modifiers and couplers at a temperature of about 50.degree. to 200.degree. Farenheit, preferably about 150.degree. F. for a time sufficient to form a homogeneous mixture. This time will generally be less than two hours and usually will be ready in about one-half hour depending on the size of the batch which is being prepared.

The resulting composition is then mixed with a suitable oxidizing agent such as hydrogen peroxide. Generally equal amounts of the dye composition are mixed with the peroxide as a 6% solution in water (about two ounces of each per head of hair) and the resulting mixture is then placed in contact with the hair which is to be dyed for a time sufficient to effect dyeing thereof. This will generally be about 20 to 60 minutes depending upon the depth which is desired. Generally the time will be about 30 minutes to 45 minutes. Thereafter the dye composition is washed off the hair so dyed.

Thus, a composition has been described which is essentially free of mutagenic phenylenediamines, derivatives thereof and nitro compounds. The composition is found to have little or no irritancy or sensitization and does not result in damage to the hair. It is easy to apply in a short period of time, has good stability and produces the illusion of natural color on the hair. It has a high degree of coverage, does not stain the hands or scalp and is permanent under normal conditions. It is found to be fast to light, perspiration and shampooing.

The following substances are measured and placed in a suitable mixing vessel.

The mixture is heated to 150.degree. for 30 minutes while stirring regularly until a homogeneous mixture is obtained. This mixture is then used to prepare the composition of the invention.

The following examples are given as a representation of the composition of the invention, but they are not to be read in a limiting sense.

The following amounts of ingredients are preweighed in a suitable vessel and added to sufficient quantity of the base prepared according to the above Preparation to make a total of a 100 gram mixture of a composition useful for a dark auburn hair dye.

The following amounts of ingredients are preweighed in a suitable vessel and added to sufficient quantity of the base prepared according to the above Preparation to make a total of a 100 gram mixture of a composition useful for a light auburn hair dye.

The following amounts of ingredients are preweighed in a suitable vessel and added to sufficient quantity of the base prepared according to the above Preparation to make a total of a 100 gram mixture of a composition useful for a bright red hair dye.

Equal quantities of the composition of each of Example 1, 2 and 3 and a 6% aqueous hydrogen peroxide are mixed. The resulting mixtures are applied to swatches of human hair for 30 minutes to give the following results:

Example 1--Dark auburn

Example 2--Light auburn

Example 3--Bright Red