JPS6160810B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a novel oxidative color-forming dye (hereinafter referred to as "oxidative dye"). More specifically, a composition that can be used for dyeing keratin fibers, ie, para-amino diphenylamine or a salt thereof, and a general formula (However, R ₁ and R ₂ represent an alkyl group having 1 to 4 carbon atoms or hydrogen, but both R ₁ and R ₂ must not be hydrogen.) 2,6-diaminopyridine derivatives), 2-amino-6-hydroxypyridine, and salts thereof. Keratin fibers (especially hair or fur) A dye intermediate that develops color upon oxidation is usually used to dye it beautifully and densely by a simple and economical method.In other words, an oxidizing agent is added to a neutral or slightly alkaline aqueous solution of this dye intermediate immediately before dyeing. When the mixture is applied or impregnated onto keratin fibers, it penetrates into the keratin fibers and is oxidized there to become a water-insoluble pigment, which dyes the keratin fibers. When dyeing keratin fibers with the main intermediate, a compound called a different type of modifying intermediate is often added together with the main intermediate in order to change the dyeing. Even if the modifying intermediate is oxidized alone, it does not have the ability to dye keratin fibers, but it undergoes a condensation reaction with the main intermediate in the oxidation stage, producing tones and deep pigments that cannot be produced by the main intermediate alone. In order to dye keratin fibers (particularly hair or fur) to a deep black color with an oxidation dye that does not contain metal compounds, a modification intermediate is usually used. As,
2,4-diamino-anisole, metatolylenediamine, metaphenylenediamine, etc. are used. These modifying intermediates are usually added to main intermediates such as paraphenylenediamine, paratoluylenediamine, and paraaminodiphenylamine to produce color tones and high rigidity that cannot be produced with the main intermediate alone. Produces pigment. For example, when paraphenylenediamine, paratoluylenediamine, and paraaminodiphenylamine are oxidized alone, they only produce dark purple, brown, and dark brown pigments, respectively, but these main intermediates are combined with the above-mentioned modifying intermediates. By adding and blending it appropriately and oxidizing it, it is possible to produce a beautiful and deep black pigment. In other words, these modifying intermediates are essential materials for the black dyeing of keratin fibers, but these substances have the property of inducing mutations in living cells (hereinafter referred to as ``mutagenicity''). Because this property is correlated with carcinogenicity, the use of these modifying intermediates in dyeing keratin fibers is being regulated in developed countries in Europe and America. Therefore, in the hair and fur dyeing industry, where there is a demand for dyeing keratin fibers in a safe and deep black color, dyes that do not contain the above-mentioned modifying intermediates and are non-mutagenic to living organisms are used. It is hoped that a black oxidation dye with a strong black color will appear. In addition, as a black oxidation dye that does not contain the above-mentioned mutagenic modification intermediate, 5.5'-diamino-bis(2
-pyridyl)-amine, 4-amino-2,6-dihydroxy-pyridine, 2,4,6-triaminopyridine or 2,5-diaminopyridine as the main intermediates, but each of these has drawbacks. In other words, 5,5'-diamino-bis(2-pyridyl)-amine is not preferable because it itself is mutagenic, and 4-amino-2,6-dihydroxy-pyridine and 2,4,6-triaminopyridine are mainly used as intermediates. The black dye used in the body is expensive and
Black dyes containing 2,5-diaminopyridine as a main intermediate are not preferred because they have low sunlight susceptibility. There is also a method of dyeing hair black using oxidative dyes that contain metal compounds, but this dye is not preferred because its dyeing power is weaker than oxidative dyes that do not contain metal compounds, and it takes a long time to dye the hair. . In view of this situation, the present inventor conducted intensive research for the purpose of obtaining a non-mutagenic black oxidation dye.
The black oxidation dye of the present invention, which uses a 2,6-diaminopyridine derivative or 2-amino-6-hydroxypyridine and a salt thereof as a modifying intermediate, and uses para-aminodiphenylamine as a main intermediate, is non-mutagenic to living organisms. The inventors discovered that the material has excellent properties and rigidity, leading to the completion of the present invention. The 2,6-diaminopyridine derivative of the present invention is a modified intermediate of oxidation dyes discovered by the present inventors in 1977 (JP-A-53-141277, JP-A-54-3123).
), and it is a known fact that 2-amino-6-hydroxypyridine can be used as a modifying intermediate for oxidative dyes; furthermore, para-amino diphenylamine is the main agent for dark brown oxidative dyes. It is also a known fact that it is used as an intermediate. However, it is a newly discovered fact by the present inventor that a mixture of these pyridine-based compounds and para-amino diphenylamine can serve as an intermediate for a solid black oxidation dye without mutagenicity. No one could have predicted this. The alkyl group of the alkyl-substituted amino group shown in the 2,6-diaminopyridine derivative of the present invention has 1 to 4 carbon atoms, that is, a methyl group, an ethyl group, an n-propyl group, an iso-propyl group, Refers to n-butyl, iso-butyl, secondary butyl, or tertiary butyl. This means that the general formula

2.6-, which is represented by [Formula] and R ₃ and R ₄ are alkyl groups having 5 or more carbon atoms.
Black dyes using diaminopyridine derivatives have poor dyeing properties, and are 2,6-diaminopyridine derivatives in which both R ₃ and R ₄ are alkyl groups with zero carbon atoms, that is, the amino group is completely substituted with an alkyl group. This is because the inventor of the present invention discovered through experiments that black dyes using 2,6-diaminopyridine, which is not used as a dye, have a low degree of porosity. The oxidation dye intermediates of the present invention can be used as such or in the form of salts with inorganic or organic acids, such as hydrochlorides, sulfates, phosphates, acetates, propionates, lactates, citrates. It is possible to do so. Further, as for the mixing ratio of the main intermediate and the modifying intermediate used in the present invention, it is desirable to mix and use both in an equimolar ratio, but the ratio does not need to be an equimolar ratio. This is because even if the molar ratio of the two components is not equal and the main intermediate component is in excess, the dark brown pigment produced in the oxidation field will be overwhelming due to the strong black pigment produced from both components. This is because it does not have a large effect on the overall black tone. The present invention will be specifically explained with reference to the following reference examples and examples, but the present invention is not limited to these examples unless it departs from the gist thereof. For example, in the hair dyeing examples below, only a method using a mixture of an aqueous solution of a dye intermediate and an aqueous oxidizing agent solution is described; Adhesives (starch, seaweed powder, synthetic thickeners, gum arabic, higher alcohols, etc.) Wetting agents (surfactants, etc.)
Stabilizers (urea, phenacetin, acetanilide, ethylenediaminetetraacetic acid, sodium sulfite, ammonium thioglycolate, etc.) Swelling agents (triethanolamine, etc.) Hair tonics (Larin emulsion, etc.) Fragrances (diasmine, etc.) Propellants (1,1-difluoroethane, etc.) ) can be added and used for hair dyeing in various forms such as solid, aqueous solution, suspension, and aerosol. In addition, in the following fur dyeing examples, only a dyeing method using chromium mordant is described, but when the oxidized dye of the present invention is actually used, iron mordant and copper mordant known in the fur dyeing industry are used. and chromium/copper,
It is also possible to use a dyeing method using a mixed mordant method such as copper/iron or chromium/iron. Example 1 Para-aminodiphenylamine 1.685g (approximately 9.146g
Dissolve 0.998 g (9.146 mmol) of 2-amino-6-hydroxypyridine in 75 c.c. of water, add about 25% aqueous ammonia, and adjust the pH of the solution.
10, add 40 c.c. of hydrogen peroxide solution with a concentration of 6%, stir well, apply this to gray hair, leave it at room temperature for 20 minutes, wash it with water, dry it, and it will remove gray hair. The hair was dyed a vivid black that did not bleach even when dyed with soapy water. When a part of this dyed hair was subjected to a discoloration/fading test against sunlight in accordance with the Japanese Industrial Standards (JIS) L-0841-1974 method, its sunlight hardness was grade 5. Examples 2 to 6 and Reference Examples Hair dyes containing the following pigment intermediate as a pigment component were prepared according to the method of Example 1, and hair dyes and sunlight stiffness were obtained using the method shown in Example 1. When measurements were carried out, the results shown in Table 1 were obtained.

[Table] Example 7 100g2 of para-aminodiphenylamine in 75% water
-Amino-6-hydroxypyridine 101g and 35
Add 57g of % hydrochloric acid and dissolve well, and at about 30℃ it will become about 30%.
After adding ammonia water until the pH reached 8.0, the Urahata method (dyes and chemicals, Vol. 8, p. 109, 1963) was added.
Add 2.5 kg (dry product equivalent) of alum-tanned and chromium-mordanted white rabbit fur (according to 2013), stir at approximately 30°C for 30 minutes, and then add 333 c.c. of 30% hydrogen peroxide solution. Stirred at 30°C for 3 hours. After that, the fur was taken out, thoroughly washed with water, and dried, and the fur was dyed a bluish black with a high moisture content.
When this fur was subjected to a sunlight-induced discoloration test in accordance with the Japanese Industrial Standard (JIS) L-0841-1974 method, its sunlight hardness was grade 5. Example 8 Salmonella typhimurium (Ames-TA98 strain or TA100 strain), S-9 activator regulated by rat liver in which drug-metabolizing enzymes were induced with PCB,
A mutagenicity test was conducted on the following oxidation dye intermediate within the dosage range (10 to 1000 μg/plate) using hydrogen peroxide and hydrogen peroxide, and the results are shown in Table 2. The dye intermediates used include
There was almost no property that increased the number of mutants, and the results were good.

【table】

[Table] As described above, in the oxidative color-forming dye for keratin fibers of the present invention, a non-mutagenic, sharp and sharp black pigment can be produced by using the above-mentioned specific pigment intermediates in combination. obtained, and remarkable effects can be achieved.

Claims (1)

[Claims] 1. Para-amino diphenylamine or a salt thereof, and the general formula (However, R ₁ and R ₂ represent an alkyl group having 1 to 4 carbon atoms or hydrogen, but both R ₁ and R ₂ must not be hydrogen.) Diaminopyridine derivatives represented by 2-amino- Oxidative coloring dye for keratin fibers containing at least one compound selected from 6-hydroxypyridine and salts thereof