JPH0665643B2 - Hair dye - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention is a hair dye, and more specifically, it can significantly shorten the hair dyeing treatment time, less damage to the scalp and hair during hair dyeing, and a feeling after hair dyeing. Also relates to an excellent oxidative hair dye.

(Prior Art) Conventionally, as a hair dye used for dyeing hair, an oxidative hair dye is a permanent dye compared with other hair dyes such as a primary hair dye and a metallic hair dye. As it is called a hair agent, it has good color retention, abundant color tones, and a clear finish, so that it has become the mainstream of hair dyes in recent years.

This oxidative hair dye generally contains a dye intermediate as the main agent, and is mixed with an alkaline agent such as ammonia to adjust the pH to 9-11, and a small amount of 4-6% hydrogen peroxide stabilizes it. It is composed of a second agent whose pH is adjusted to 2-3 by blending the agent, and the first agent and the second agent are mixed immediately before the hair dyeing treatment, and the mixture is applied to the hair as a mixed solution of pH 9-10. It is something. Therefore, the alkaline agent contained in the first agent enhances the penetration and adsorption of the dye intermediate into the hair, and also has an important effect of decomposing the hydrogen peroxide in the second agent to accelerate the generation of oxygen. This oxygen has a function of destroying the melanin pigment of hair to decolorize it, and a function of oxidizing and polymerizing the dye intermediate in the first agent to form an insoluble coloring pigment inside the hair.

However, in such a conventional oxidative hair dye, it takes a long time of 30 to 40 minutes until the dye intermediate in the first agent is oxidatively polymerized to form an insoluble dye. This is accompanied by the pain of having to maintain a quiescent state for a long time, and there is a drawback in that the scalp and hair are damaged to a considerable extent because they are treated with a strong alkaline solution of pH 9 to 10 for a long time.

(Problems to be Solved by the Invention) The present invention has been made by paying attention to such drawbacks of the conventional oxidative hair dye, which is treated by the rapid progress of oxidative polymerization of the dye intermediate in the first agent. The time can be significantly shortened, and by keeping the pH of the treatment liquid near neutral,
It is an object of the present invention to provide a hair dye that reduces damage to and damage to the scalp and hair, and that also has an excellent finished feel.

(Means for Solving the Problems) As a result of various studies on the means for achieving the above object, the inventors of the present invention have found that a small amount of iron ions is allowed to coexist in the dye intermediate in the first agent to form the second agent. In addition to being able to catalytically promote the oxidation reaction by hydrogen peroxide in the solution through iron ions, the alkaline agent compounded in the first agent also uses an organic amine having a weak alkalinity instead of ammonia,
The inventors have found that the above object can be effectively achieved by maintaining the pH of the mixed solution of the first agent and the second agent near neutrality, and have completed the present invention.

That is, the present invention contains an oxidative dye intermediate as an active ingredient and an iron ion compound as an iron ion in an amount of 1 to 10
A hair dye characterized by comprising a weakly alkaline first agent containing 0 ppm and an acidic second agent containing hydrogen peroxide as an active ingredient, and being neutral or slightly alkaline when blended.

In the present invention, the dye intermediate contained in the first agent of the hair dye as an active ingredient is composed of an electrophilic reagent precursor which produces an insoluble color-forming polymer by a reaction and a coupling agent. Among these, electrophilic reagent precursors include p-phenylenediamine, toluene 2,5-diamine, p-aminophenol, and the like, while coupling agents include m
-Phenylenediamine, m-aminophenol, resorcin, 2,6-diaminopyridine, α-naphthol, 5-
Amino-0-cresol and the like can be mentioned.

By combining these dye intermediates and adjusting the pH, it is possible to produce color forming polymers of various color tones from black to brown and red.

Next, ferric chloride is most preferable as the iron ion compound added to the first agent in a trace amount, but any compound that produces divalent or trivalent iron ions in the liquid may be used. ,
Ferric sulfate, ferrous ammonium sulfate, ferric ammonium sulfate, ferric citrate, ammonium ferric citrate,
Ferrous oxalate, ferrous lactate, ferric pyrophosphate and the like can also be used.

These iron ion compounds are 1 in the first agent as iron ions.
~ 100ppm is added. If the addition amount is less than 1 ppm, the effect is not sufficient, and if it exceeds 100 ppm, the dye intermediate itself reacts in the first agent to form an insoluble polymer, and the hair dyeing effect cannot be obtained, which is not preferable.

Further, as an alkali agent as a penetration enhancer to be blended in the first agent, ammonia is a strong alkali and therefore causes the same problems as conventional hair dyes. Is generated to inhibit the action function of iron ions in the present invention, which is not preferable. Therefore, an organic amine is used as an alkaline agent which does not cause such a problem. Examples of the organic amine include monoethanolamine, diethanolamine, triethanolamine and the like.

The dye intermediates, iron ion compounds, organic amines, etc. described above are solvents, cream bases, and the like which are usually added to hair dyes.
It is made the first agent by dissolving it in purified water together with a surfactant, an emulsifier, a fragrance and the like. The pH of the first agent thus prepared is about 8.5.

Next, the second agent is hydrogen peroxide (H ₂ O ₂ ) 4% in the total amount of the second agent.
It is obtained by adding a small amount of a stabilizer and a pH adjusting agent to purified water to adjust the total pH to about 2 to 3 while containing about 6 to 6% by weight.

The above first and second agents are about 1: 1 (weight ratio) when used.
The mixture is mixed at a ratio of, and the pH is adjusted to a range of about 6.5 to 8.5 before use.

(Operation) The mechanism of formation of the color-forming polymer from the dye intermediate in the present invention is as follows.

That is, as an electrophilic reagent precursor constituting a dye intermediate
Example of using p-phenylenediamine (PPD)
First, PPD is calculated by the following formula (1).
Is converted into p-phenylenediimine (PPDI).PPDI is a protonated diiminium ion (PPD
I ) Is in equilibrium with this PPDI Is the electrophilic reagent
A coupling agent rich in electrons as shown in formula (2)
(C) and PPDI + Coupling agent (C) → insoluble color-forming polymer ...
(2) Reacting and finally developing insoluble color through dimer and trimer
This produces a polymer.

In this case, the reaction of the formula (2) is instantaneously and rapidly performed, so that the rate-determining step of the reaction is from PPD to PPDI in the formula (1).
It is in the generation speed of.

On the other hand, PPD has an equilibrium relationship between PPDI and divalent iron ion (Fe ²⁺ ) as shown in the following formula (3) in the presence of trivalent iron ion (Fe ³⁺ ), but PPD + 2Fe ^{3 +} PPDI + 2Fe ²⁺ (3) Divalent iron ion (Fe ²⁺ ) is oxidized by hydrogen peroxide (H ₂ O ₂ ) as shown in the following formula (4) Fe ²⁺ + 2H ₂ O ₂ → Fe ³⁺ + 2H ₂ O + O ₂ (4) Immediately returns to trivalent iron ion (Fe ³⁺ ), so formula (3)
The equilibrium of PPD always proceeds in the direction of the right arrow, and PPD is rapidly converted to PPDI by Fe ^{3+ in} the presence of H ₂ O ₂ .

Therefore, when the above reaction mechanism is refined, In the order of sea urchin, and when added with divalent iron ion (Fe ²⁺ ), the reaction proceeds in the order of, while the amount of iron ion is 3
By repeating redox of valency, the reaction product eventually becomes a colored insoluble oxidative dye polymer and hydrogen peroxide decomposition product,
The divalent or trivalent iron ion compound functions as a catalyst for the reaction.

As described above, according to the present invention, as compared with the reaction of PPD which is oxidized by H ₂ O ₂ to produce PPDI like the conventional oxidative hair dye, the reaction of being oxidized by Fe ³⁺ to produce PPDI is performed. Much faster. Also, after PPDI is produced, the coupling agent (C)
As described above, the reaction of reacting with to form an insoluble color-forming polymer is extremely fast, so that the hair dyeing treatment time is extremely shortened.

(Example) Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples.

[Preparation of hair dye]

First, the 1st agent of this invention of Examples 1-4 was prepared using the compounding agent shown to the left column of the following table.

First agent Moreover, the 2nd agent mix | blended with the 1st agent of Examples 1-4 was prepared using the following compounding agents.

Second agent The above-mentioned first agent and second agent were mixed at a ratio of 1: 1 (weight ratio) to prepare a hair dye of the present invention immediately before treatment.

The pH of the prepared hair dye and the pH of the comparative example (conventional commercial product) were as follows.

[Dyeing test] Approximately 1 g of white hair bundles of yak were bundled, 20 g of the hair dyes of Examples 1 to 4 and Comparative Example were applied and allowed to stand naturally, and the color development time and the obtained color tone were observed. The results are shown in Table 1.

[Hair hair dyeing test] Hair of humans with white hair was treated with the hair dyes of Examples 1 to 4 and Comparative Example, and the treatment time and the color tone as a dyeing state,
Table 2 shows the results of evaluating the touch and gloss of each of 10 panels. In the table, ◯ indicates better than Comparative Example, and Δ indicates equivalent.

From the above test results, the various processing time by the hair dye of the present invention shown in Examples 1 to 4 is 5 to 10 minutes, which can be greatly shortened compared to 30 minutes of the conventional hair dye. The hair color is evenly dyed in various colors from black blue to reddish brown.
It was also found that the hair after treatment had a significantly superior feel to the conventional product, and the gloss was equal to or superior to that of the conventional product.

(Effects of the Invention) As is apparent from the effects described in detail above and the results of the examples, the hair dye of the present invention contains an iron ion compound in the first agent containing an oxidative dye intermediate as an active ingredient. Since the inclusion of a trace amount of the electrophilic reagent has succeeded in significantly promoting the production of the electrophilic reagent by the oxidation of the electrophilic reagent precursor as compared with the conventional oxidation using only hydrogen peroxide, the reaction between the electrophilic reagent and the coupling agent has been succeeded. The treatment time required for producing an insoluble color-forming polymer based on the above is extremely shortened as compared with the conventional hair dye, and an effect that almost all the pains to be given to the recipient can be eliminated can be obtained. Further, since the hair dye of the present invention does not use a strong alkaline agent such as ammonia, its pH is adjusted to a neutral range of 6.5 to 8.5 by using an organic amine, so that On the other hand, there are advantages that there is no risk of damaging the scalp and hair, and that the feeling and gloss of the finish are remarkably excellent.

Claims (1)

[Claims] 1. A weakly alkaline first agent containing an oxidative dye intermediate as an active ingredient and an iron ion compound as an iron ion in an amount of 1 to 100 ppm, and an acidic second agent containing hydrogen peroxide as an active ingredient. A hair dye, which is characterized by comprising: and becoming neutral to slightly alkaline when blended.