Oxidation hair dyes based upon tetraaminopyrimidine developers and monohydroxyindazole couplers

An aqueous hair dye preparation comprising an oxidation dyestuff combination of a developer component consisting of a tetraaminopyrimidine derivative or a water-soluble acid addition salt thereof and a coupler component consisting of a monohydroxyindazole compound, as well as a process for dyeing hair by utilizing this oxidation dyestuff combination.

THE PRIOR ART 
Of great importance for the dyeing of hair are the so-called oxidation 
dyestuffs because of their intensive colors and very good fastness. These 
dyestuffs are formed by the oxidative coupling of a developer component 
with a coupling component. The developers customarily used are nitrogenous 
bases, such as p-phenylenediamine derivatives, diaminopyridines, 
4-aminopyrazolone derivatives or heterocyclic hydrazones. Useful as 
so-called coupling components are m-phenylenediamine derivatives, phenols, 
naphthols, resorcinol derivatives and pyrazolones. 
Good oxidation dyestuff components for hair dyeing must fulfill all of the 
following requirements. 
They have to be able to develop a sufficient intensity of the desired color 
shades when oxidatively coupled with the respective developer component or 
coupling component. Furthermore, they have to possess a capacity for being 
absorbed by human hair, which capacity ranges from sufficient to very 
good; and in addition, they should be unobjectionable from toxicological 
and dermatological viewpoints. 
As developers, it is customary to use the class of compounds consisting of 
substituted or unsubstituted p-phenylenediamines. However, this class of 
compounds has the disadvantage that sensitivity reactions and subsequently 
severe allergies are caused in numerous persons. The developers which have 
been recently proposed for avoiding these dermatological disadvantages are 
not always fully satisfactory with respect to their technical application. 
U.S. Pat. No. 4,003,699, Jan. 18, 1977, discloses oxidation hair dyes based 
upon tetraaminopyrimidine developers which can react with the known 
couplers generally used in oxidation hair dyestuffs to give very 
intensive, varying shades which previously could not be obtained with 
these known couplers. U.S. Pat. No. 4,003,699 also discloses the special 
usefulness of its tetraaminopyrimidines employed as developers in 
combination with certain m-aminophenols as blue-coupling components. 
It is further disclosed in the above patent that the tetraaminopyrimidines 
disclosed therein are characterized by very good fastness of the dyeings 
produced with them, good water-solubility, good storage stability, and 
toxicological and dermatological harmlessness. 
Among the various tints producable by oxidation hair dyes, great importance 
is attached to the intensive yellow and yellowish brown tints. The 
compounds normally used as yellow coupler components have not produced 
satisfactory results when combined with the tetraaminopyrimidines which 
otherwise give very satisfactory results when used as developer 
components. Thus, the task arose of providing yellow coupler components 
which, when combined with the tetraaminopyrimidines used as developer 
substances, produce intensive yellow to yellowish-brown tints which meet 
all the requirements with respect to fastness, stability and toxicological 
and dermatological harmlessness desirable in oxidation hair dyes. 
OBJECTS OF THE INVENTION 
An object of the invention is to provide usable oxidation hair dyes 
containing suitable components which optimally satisfy the above 
requirements. 
Another object of the present invention is to provide an oxidation dyestuff 
combination of a developer component and a coupling component, which is 
based on tetraaminopyrimidines as the developer component and 
monohydroxyindazole compounds as the coupler component. 
These and further objects of the present invention will become apparent as 
the description thereof proceeds.

DESCRIPTION OF THE INVENTION 
The present invention provides a composition and process for dyeing hair 
based upon an oxidation dyestuff combination of a developer component 
which is a tetraaminopyrimidine and a coupling component which is a 
monohydroxyindazole compound. It has now been found that the 
above-specified requirements can be fulfilled to an especially significant 
extent by the use of hair coloring preparations that are based on 
oxidation dyestuff combinations containing tetraaminopyrimidines of the 
formula 
##STR1## 
and their inorganic or organic water-soluble acid addition salts as 
developers, in which R.sub.1 to R.sub.6 are each selected from the group 
consisting of hydrogen, alkyl having 1 to 4 carbon atoms, aryl, 
substituted aryl and --(CH.sub.2).sub.n --X, in which n is an integer from 
1 to 4, and X is selected from the group consisting of hydroxy, halogen 
and --NR.sub.7 R.sub.8 wherein R.sub.7 and R.sub.8 are selected from the 
group consisting of hydrogen and alkyl having 1 to 4 carbon atoms and can 
form with the nitrogen atom a heterocyclic ring which may contain one 
additional nitrogen atom or an oxygen atom, and wherein R.sub.1 and 
R.sub.2, or R.sub.3 and R.sub.4, or R.sub.5 and R.sub.6, together with the 
nitrogen atom form a five-membered or six-membered hetrocyclic ring 
containing one or two nitrogen atoms, or one nitrogen atom and one oxygen 
atom, and containing at least one monohydroxyindazole of the formula 
##STR2## 
wherein R is selected from the group consisting of hydrogen and an alkyl 
radical having 1 to 4 carbon atoms, X is selected from the group 
consisting of hydrogen, a halogen atom, and an alkyl radical having 1 to 4 
carbons, and n is the integer 1 or 2 and when n is 2, X can be the same or 
different. 
More particularly, the present invention is directed to an aqueous 
preparation for the dyeing of hair consisting essentially of (1) from 0.2% 
to 5% by weight of an oxidation dyestuff combination of a developer 
component, and a coupling component in substantially equimolar amounts, 
said developer component consisting essentially of (A) a 
tetraaminopyrimidine of the formula 
##STR3## 
wherein R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5 and R.sub.6 are each 
selected from the group consisting of hydrogen, phenyl, alkyl having 1 to 
4 carbon atoms, phenylalkyl having 7 to 10 carbon atoms, phenylalkenyl 
having 7 to 10 carbon atoms, 
EQU X--(CH.sub.2).sub.n -- 
wherein n is an integer from 1 to 4, and X is selected from the group 
consisting of hydroxyl, halogen and NR.sub.7 R.sub.8 --in which R.sub.7 
and R.sub.8 are each hydrogen or alkyl having 1 to 4 carbon atoms, and 
together with the nitrogen atom R.sub.7 and R.sub.8 form a member selected 
from the group consisting of a 5 to 6 membered heterocyclic ring 
optionally containing an additional nitrogen atom or oxygen atom, and 
wherein R.sub.1 and R.sub.2, or R.sub.3 and R.sub.4, or R.sub.5 and 
R.sub.6, together with the nitrogen atom form a five to six membered 
heterocyclic ring optionally containing another nitrogen or oxygen atom in 
the ring and (B) a water-soluble acid addition salt of (A), and said 
coupler component consisting essentially of at least one 
monohydroxyindazole of the formula. 
##STR4## 
wherein R is selected from the group consisting of hydrogen and an alkyl 
radical having 1 to 4 carbon atoms, X is selected from the group 
consisting of hydrogen, a halogen atom, and an alkyl radical having 1 to 4 
carbons, and n is the integer 1 or 2 and when n is 2, X can be the same or 
different; (2) from 0% to 5% by weight of a direct dyestuff; (3) 0% to 30% 
by weight of a surfactant; (4) from 0% to 25% by weight of thickeners; and 
(5) the balance up to 100% by weight of water. 
A particularly preferred subgenus of the above-mentioned developer 
component is wherein R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5 and 
R.sub.6 are each selected from the group consisting of hydrogen, methyl, 
ethyl, isopropyl, n-propyl, butyl, phenyl, benzyl and benzylidene, or 
--(CH.sub.2).sub.n --X, and wherein R.sub.1 and R.sub.2, or R.sub.3 and 
R.sub.4, or R.sub.5 and R.sub.6, together with the nitrogen atom form a 
substituent selected from the group consisting of piperidino and 
morpholino; and wherein n is 1, 2 or 3 and X is selected from the group 
consisting of hydroxyl, halogen and --NR.sub.7 R.sub.8 in which R.sub.7 
and R.sub.8 are each hydrogen or alkyl having 1 to 4 carbon atoms. 
The above tetraaminopyrimidines are disclosed in U.S. Pat. No. 4,003,699, 
the teachings of which are incorporated herein by reference. 
The tetraaminopyrimidines which are to be used as developer components 
according to the invention can be used either as such or in the form of 
their water-soluble acid addition salts with non-toxic inorganic acids or 
organic acids, such as for example, hydrochloric acid, sulfuric acid, 
phosphoric acid, acetic acid, propionic acid, lactic acid or citric acid. 
The preparation of most tetraaminopyrimidines to be used as developer 
components according to the invention is already known in the literature 
and can be taken from the monograph by D. J. Brown, in the series 
"Heterocyclic Compounds", Interscience Publishers, 1962, Vols. I and II, 
"The Pyrimidines". The preparation of some of the tetraaminopyrimidines of 
the invention is disclosed in U.S. Pat. No. 4,003,699. 
To synthesize the tetraaminopyrimidine compounds to be used according to 
the invention, the starting material generally is a 2,4,6-aminopyrimidine, 
into which the 5-amino group is introduced by nitrosation and subsequent 
reduction. It is also possible to start from the correspondingly 
substituted triaminoalkylmercaptopyrimides and to replace the 
alkylmercapto group with an amino group. The latter method is especially 
suitable for the introduction of substituted amino groups into the 2-, 4-, 
or 6-positions of the pyrimidine ring. Suitable examples of developer 
components to be used according to the invention, are for example: 
2,4,5,6-tetraamino-pyrimidine, 
4,5-diamino-2,6-bis(methylamino)-pyrimidine, 2,5-diamino-4,6-bis-(methylam 
ino)-pyrimidine,4,5-diamino-6-(butylamino)-2-(dimethylamino)-pyrimidine, 
2,5-diamino-4-(diethylamino)-6-(methylamino)-pyrimidine,4,5-diamino-6-(die 
thylamino)-(2-dimethylamino)-pyrimidine, 
4,5-diamino-2-(diethylamino)-6-(methylamino)-pyrimidine, 
4,5-diamino-2-(dimethylamino)-6-(ethylamino)-pyrimidine,4,5-diamino-2-(dim 
ethylamino)-6-(isopropylamino)-pyrimidine, 4,5 
diamino-2-(dimethylamino)-6-(methylamino)-pyrimidine, 
4,5-diamino-6-(dimethylamino)-2-(methylamino)-pyrimidine, 
4,5-diamino-2-(dimethylamino)-6-(propylamino)-pyrimidine, 
2,4,5-triamino-6-(dimethylamino)-pyrimidine, 
4,5,6-triamino-2-(dimethylamino)-pyrimidine, 
2,4,5-triamino-6-(methylamino)-pyrimidine, 
4,5,6-triamino-2-(methylamino)pyrimidine, 
4,5-diamino-2-(dimethylamino)-6-piperidinopyrimidine, 
4,5-diamino-6-(methylamino)-2-piperidino-pyrimidine, 
2,4,5-triamino-6-piperidino-pyrimidine, 
2,4,5-triamino-6-anilino-pyrimidine, 
2,4,5-triamino-6-(benzylamino)-pyrimidine, 
2,4,5-triamino-6-(benzylideneamino)-pyrimidine, 
4,5,6-triamino-2-piperidino-pyrimidine, 
5-amino-2,4,6-tris-(methylamino)pyrimidine, 
2,4,5-triamino-6-(di-n-propylamino)pyrimidine, 
2,4,5-triamino-6-morpholino-pyrimidine, 
2,5,6-triamino-4-(dimethylamino)-pyrimidine, 
4,5,6-triamino-2-morpholino-pyrimidine, 
2,4,5-triamino-6-(.beta.-hydroxyethyl-amino)pyrimidine, 
4,5,6-triamino-2-[(.beta.-aminoethyl)amino]-pyrimidine, 
2,5,6-triamino-4-[(.beta.-methylamino)-ethylamino] pyrimidine, 
2,5-diamino-4,6[bis-(.gamma.-diethylamino)-propylamino]-pyrimidine, 
4,5-diamino-6-[(B-hydroxyethyl)-amino]-2-(methylamino)pyrimidine, 
5-amino-2,4,6-(triethylamino)-pyrimidine, and 
5-amino-6anilino-2,4-[bis-(.beta.-hydroxyethyl)-amino]-pyrimidine. 
According to the invention, the tetraaminopyrimidines as developers are 
used in combination with coupler compounds of the formula 
##STR5## 
wherein R is selected from the group consisting of hydrogen and an alkyl 
radical having 1 to 4 carbon atoms, X is selected from the group 
consisting of hydrogen, a halogen atom, and an alkyl radical having 1 to 4 
carbons, and n is the integer 1 2 and when n is 2, X can be the same or 
different, or any combination of these monohydroxyindazole compounds. 
Yellow coupler components that can be used according to the invention are, 
for example, 4-hydroxyindazole, 5-hydroxyindazole, 6-hydroxyindazole, 
7-hydroxyindazole, 7-hydroxy-1-methylindazole, 4-hydroxy-6-methylindazole, 
7-hydroxy-6-methylindazole, 7-hydroxy-4,6-dimethylindazole, 
6-hydroxy-7-bromoindazole, 6-hydroxy-7-chlorindazole or 
6-hydroxy-5,7dichloroindazole. 
The monohydroxyindazoles are compounds known in the literature whose 
production is described in detail in the Journal of the Chemical Society, 
1955, pg. 2412 ff., in the Annalen der Chemie, Vol. 404 (1914), pg. 81 
ff., and in the Monatsheften fur Chemie Vol., 90 (1959), pg. 96 ff. 
Very advantageous results have been obtained using the 
monohydroxyinadazoles wherein R and X are hydrogen and n is 1, as e.g. 
5-hydroxyindazole and 6-hydroxyindazole. Also very suitable are those 
monohydroxyindazoles wherein X is methyl or a halo substituent selected 
from bromo or chloro, especially chloro, such as 
4-hydroxy-6-methylindazole, 7-hydroxy-6-methylindazole, and 
6-hydroxy-7-chloroindazole. Among those monohydroxyindazoles wherein X is 
halogen or alkyl, the compounds where R is hydrogen are particularly 
valuable compounds. 
In the hair coloring preparations according to the invention, the coupler 
substances are generally used in substantially equimolar amounts, relative 
to the developer substances used. Although an equimolar amount is 
preferred, it is possible to use more or less of either component in the 
molar range of 2:1 to 1:2, more preferably up to a 10% excess of 
deficiency. 
Furthermore, the developer component and the coupling component may be used 
as pure ingredients or as mixtures. Not only can the developer component 
consist of mixtures of the tetraaminopyrimidines to be used according to 
the invention, but the coupler substance can also consist of mixtures of 
the above-mentioned monohydroxyindazoles. 
In addition, the hair coloring preparations according to the invention can 
contain admixtures of other customary developing components. Besides 
developer and/or coupler components they, if necessary, also contain the 
customary direct dyestuffs in case the latter are needed for obtaining 
certain shades. From 0% to 5% direct dyestuffs may be employed. Some 
examples of such other customary developers are p-phenylene diamine 
derivatives, diaminopyridines, 4-aminopyrazolone derivatives and 
heterocyclic hydrazones. Some examples of such other customary couplers 
are m-phenylene diamine derivatives, phenols, naphthols, resorcinol 
derivatives and pyrazolones. Besides these, yet other such conventional 
developers and couplers will be readily perceived by those skilled in art. 
As in the case of other oxidation hair dyes, the oxidative coupling, i.e., 
the developing of the dye, can in principle be effected by atmospheric 
oxygen. However, it is advantageous to use chemical oxidizing agents. 
Suitable examples are especially hydrogen peroxide or its products of 
addition to urea, melamine and sodium borate, as well as mixtures of such 
hydrogen peroxide addition products with potassium peroxydisulfate. 
As developer components the tetraaminopyrimidines according to the 
invention have the advantage that the readily yield fully satisfactory 
hair dyeing results in oxidative coupling with atmospheric oxygen. Thus 
hair damage by the oxidizing agents, otherwise used in oxidative coupling, 
can be avoided. But if a brightening or bleaching effect is desired in the 
hair, in addition to the coloring effect, then the concurrent use of 
chemical oxidizing agents is necessary. 
For the application, the hair dyes according to the invention are 
incorporated into suitable aqueous cosmetic preparations, such as creams, 
emulsions, gels or simple solutions and immediately before application to 
the hair, one of the above-mentioned oxidizing agents is added. These hair 
dyeing preparations contain coupling and developing components in amounts 
of from 0.2% to 5% by weight, preferably from 1% to 3% by weight. 
For the preparation of creams, emulsions or gels, the dye components are 
mixed with the additional ingredients customarily used in such 
preparations. Such additional ingredients are, for example, wetting agents 
or emulsifiers of the anionic or nonionic type, such as 
alkylbenzenesulfonates, higher fatty alcohol sulfates, higher 
alkylsulfonates, higher fatty acid alkanolamides, addition products of 
ethylene oxide on higher fatty alcohols, thickeners, such as methyl 
cellulose, starch, higher fatty alcohols, paraffin oil and higher fatty 
acids. Furthermore, perfumes and hair-conditioning and grooming agents, 
such as pantothenic acid and cholesterol may be included. 
Effective amounts of the above-mentioned additives are those customarily 
employed for this purpose. For example, effective amounts of wetting 
agents and emulsifiers range from 0.5% to 30% byweight, preferably from 1% 
to 15% by weight; and for thickeners, an effective amount ranges from 0.1% 
to 25% by weight, preferably from 1% to 15% by weight, based in each case 
on the total weight of the preparation. As a lower limit for the above 
additives, a zero percent lower limit is possible, if none of the additive 
is utilized. 
The hair coloring preparations according to the invention can be applied in 
a weakly acid medium, a neutral medium or especially in an alkaline 
medium, preferably at a pH of 8 to 10, regardless of whether a solution, 
an emulsion, a cream, or a gel is employed. 
These preparations are applied at a temperature which usually ranges from 
15.degree. C. to 40.degree. C. and preferably is room temperature. 
After the preparation has been allowed to react for about 30 minutes, the 
hair coloring preparation is removed from the hair to be dyed, by rinsing. 
Then the hair is washed with a mild shampoo, and finally is dried. 
When combined with the tetraaminopyrimidine developers, the 
monohydroxyindazoles to be used in accordance with the present invention, 
as coupler components, yield very intensive yellow tints which are 
distinguished by particularly satisfactory fastness properties with 
respect to light, penetrating properties and toxicological harmlessness. 
The following examples are merely illustrative of the present invention 
without being deemed limitative in any manner thereof. 
EXAMPLES 
The following compounds were used as coupler components in the examples 
presented hereinafter: 
Coupler component: 
K 1: 5-hydroxyindazole 
K 2: 6-hydroxyindazole 
The following compounds were used as developer components in the examples 
presented hereinafter: 
Developer component: 
E 1: 2,4,5,6-tetraaminopyrimidine 
E 2: 2,4-bisdimethylamino-5,6-diaminopyrimidine 
E 3: 2-dimethylamino-4,5,6-triaminopyrimidine 
E 4: 2-morpholino-4,5,6-triaminopyrimidine 
E 5: 2,6-bisdimethylamino-4,5-diaminopyrimidine 
E 6: 2-piperidino-4,5,6-triaminopyrimidine 
E 7: 2-methylamino-4,5,6-triaminopyrimidine 
E 8: 6-anilino-2,4,5-triaminopyrimidine 
EXAMPLE 1 
The hair dyes according to the invention were used in the form of a cream 
emulsion. 0.01 mole of the tetraaminopyrimidines and 0.01 mole of the 
monohydroxyindazoles listed in the following Table were in each case 
incorporated into an emulsion containing 
10 parts by weight of fatty alcohols having 12 to 18 carbon atoms, 
10 parts by weight of fatty alcohol sulfate (sodium salt) having 12 to 18 
carbon atoms, and 75 parts by weight of water. 
The pH value of the emulsion was then adjusted to 9.5 by means of ammonia, 
and the emulsion was made up to 100 parts by weight with water. Oxidative 
coupling was effected either with atmospheric oxygen or with a 1% hydrogen 
peroxide solution acting as an oxidation agent, 10 parts by weight of the 
hydrogen peroxide solution being added to 100 parts by weight of the 
emulsion. The particular dyeing cream, with or without additional 
oxidation agent, was applied to human hair which was 90% grey and which 
had not been specially pretreated, and the cream was left on the hair for 
30 minutes. After the dyeing process was completed, the hair was washed 
with a conventional shampoo and subsequently dried. The colors obtained 
are given in the following Table. 
TABLE 
______________________________________ 
Shade Obtained 
Ex- With Air With 1% H.sub.2 O.sub.2 
ample Developer Coupler Oxidation Solution 
______________________________________ 
2 E 1 K 1 Honey Yellow 
Honey yellow 
3 E 2 K 1 Grey Greyish Yellow 
4 E 1 K 2 Honey yellow 
Honey yellow 
5 E 3 K 2 Auburn Yellow 
6 E 4 K 2 Auburn Yellow 
7 E 5 K 2 Greyish brown 
Bright red 
8 E 6 K 2 Yellow blonde 
Honey yellow 
9 E 7 K 2 Auburn Yellow 
10 E 8 K 2 Blonde Greyish yellow 
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