EP1732848A1

EP1732848A1 - Basic aluminium halogenide complexes

Info

Publication number: EP1732848A1
Application number: EP05728684A
Authority: EP
Inventors: Norbert Roesch
Original assignee: Clariant Produkte Deutschland GmbH
Current assignee: Clariant Produkte Deutschland GmbH
Priority date: 2004-03-26
Filing date: 2005-03-22
Publication date: 2006-12-20
Also published as: US20080069788A1; JP2007530482A; DE102004015025A1; WO2005092795A1

Abstract

The invention relates to basic aluminium halogenide complexes obtained by reacting aluminium metal with hydrohalic acid and an organic acid. According to the invention, either the aluminium metal is dissolved in a mixture of hydrohalic acid and organic acid or the aluminium metal is first dissolved in the hydrohalic acid and the organic acid is then added. The basic aluminium halogenide complexes thus modified by the incorporation of ligands of organic acids exhibit an improved action as antiperspirant active ingredients.

Description

Basic aluminum halide complexes

Basic aluminum halides in the form of chlorides are used as an active ingredient in cosmetic preparations such as antiperspirants or astringents. The far better-acting aluminum chloride hexahydrate is ruled out for this application because of its skin-irritating effect. It is used for therapeutic purposes in the presence of hyperhidrosis (sweating sickness). The difference between the aluminum chlorides mentioned is that the basic salts form oligomeric and polymeric aluminum species (see S. Schönherr, H. Görz, D. Müller and W. Gessner; in Z.anorg.allg. Chem. 476, 188-194 (1991)), which show a reduced effectiveness in antiperspirants.

For many years, attempts have therefore been made to increase the effectiveness of the basic aluminum chlorides while maintaining good skin compatibility. In patents EP 0 308 937; EP 0 183 171; US 4,359,456; EP 0 191 628 describes basic aluminum halides, preferably chlorides, which are subjected to a heat treatment. The solutions obtained were examined by gel permeation chromatography (GPC) with regard to their polymer distribution. The heat-treated samples show a degradation of polymeric species and thus an increased effectiveness in antiperspirants. However, it is also known from the literature that the distributions of the different polymeric species are reversible equilibria, and therefore the activation is lost over time in protic solvents.

Another way to present more effective antiperspirant active ingredients is the use of mixed compounds which consist of combinations of basic aluminum halides (preferably chlorides), zirconium salts and glycine. Various manufacturing methods are described in US 4,871,525; Find US 4775 528 and DE 25 37359. A further increase in the effectiveness of the zirconium-aluminum mixed salts is described in EP 0 653 203; WO 02/34223; WO 0234223; EP 0 455489 and EP 0 444564. However, the disadvantage of zirconium aluminum salts is the high price for the available zirconium raw materials.

EP 1 364 651 describes the use of a mixture of basic aluminum hydrate and trivalent aluminum salts which contain organic ligands for the production of pharmaceutical preparations which have a skin-swelling effect. Use as an antiperspirant active ingredient is neither described there, nor can such an antiperspirant effect be derived for the person skilled in the art from this document. In the CTFA database, the Na salt of a complex of lactic acid and aluminum chlorohydrate (Choracel) and its effect as a cosmetic astringent is known. However, this product is not a real aluminum-lactic acid complex, but a mixture of aluminum chlorohydrate and lactic acid. Further complexes of aluminum salts, possibly zirconium salts, and hydroxy acids are described in US 3,542,919, US 3,553,316 and US 3,991,176. In the manufacture of these products, however, the hydroxy acid is added to the finished aluminum salt, but not, as in the present invention, in the manufacture of the aluminum salt. As a result, the addition of the hydroxy acid in this prior art can have no influence on the distribution of the polymeric fractions.

The object of the present invention is to improve the effectiveness of basic aluminum chlorides as an antiperspirant active ingredient by reducing the formation of polymeric aluminum structures. This problem was solved by the incorporation of organic acids as complex ligands in the basic aluminum halides.

The invention relates to basic aluminum halide complexes obtained by reacting aluminum metal with hydrohalic acid and an organic acid, either dissolving the aluminum metal in a mixture of hydrohalic acid and organic acid or the Aluminum metal first dissolves in the hydrohalic acid and then the organic acid is added. The first variant, ie the dissolution of the aluminum metal in the mixture of hydrohalic acid and organic acid, is preferred.

HBr, but in particular HCl in the form of its aqueous solution, can be used as the hydrogen halide. The concentration of the hydrohalic acid is preferably 1 to 10% by weight, preferably 5% by weight.

Suitable organic acids are in particular those which contain 1 to 5 carbon atoms. These organic acids can be mono-, di- or tricarboxylic acids, but aminocarboxylic acids or hydroxycarboxylic acids are also possible, the latter being preferred. Examples of such acids are glycolic acid, lactic acid, tartronic acid, tartaric acid, malic acid and glycine.

The ratio of hydrohalic acid to organic acid can be between 10 to 90 mol% for each of the two acids. A mixture of 20 to 50 mol% of hydrohalic acid and 50 to 80 mol% of organic acid is preferred. The concentration of the hydrohalic acid is as stated above.

The aluminum metal is then dissolved in this acid mixture. The aluminum metal can be in the form of powder, grit, granules or as bars. The reaction is preferably carried out at temperatures from 20 to 100 ° C., preferably at 50 to 100 ° C. The reaction runs until the desired atomic ratio of Al to halogen or to the anion of the organic acid has been established in the reaction solution.

The aqueous solution of the basic aluminum halide thus obtained can be used directly as an antiperspirant active ingredient. In order to establish certain ligand ratios in the complex, one can also add hydrohalic acid and / or organic acid after the reaction between aluminum metal and the acid mixture. It is also advantageous to adjust the aqueous solution of the basic aluminum complex to a pH of about 4 to 5 by adding a buffer substance. In particular, σ-amino acids, for example glycine, are suitable as buffer substances. The aqueous solutions of the basic aluminum complexes obtained in this way are distinguished by the fact that the proportions of Al polymer are significantly reduced, while at the same time the proportion of Al monomers and Al oligomers increases. These solutions can be processed directly as an antiperspirant active ingredient. However, these basic aluminum complexes according to the invention can also be mixed with other customary antiperspirant active ingredients, for example with Al-zirconium-glycine-chloro complexes or other metal complexes which contain Zr, Hf, Ti or Sn. In this variant, too, it can be advantageous to add a buffer substance, for example an amino acid such as glycine, in order to set a pH of 4-5.

Examples

example 1

In a column-like vessel 60 cm long and 9 cm in diameter with jacket heating and attached cooler, about 2.5 kg of aluminum pieces in the form of small bars, each weighing about 11 g, were placed and stripped with dilute hydrochloric acid. A 1: 1 mixture of hydrochloric acid and glycolic acid was then introduced. After filling the solution and heating to about 100 ° C, the aluminum metal was attacked with hydrogen evolution. The progress of the reaction is monitored by determining the aluminum and chloride content of the solution. At an aluminum: chlorine atomic ratio of 3.3 to 1, the reaction was terminated by draining off the solution. The aluminum complex thus obtained was used for the active ingredients described in Examples 3 and 6.

Example 2

In a column-like vessel with a length of 60 cm and a diameter of 9 cm Jacket heating and attached cooler were presented with approximately 2.5 kg of aluminum pieces in the form of small bars each weighing approximately 11 g and stripped with dilute hydrochloric acid. A 1: 1 mixture of hydrochloric acid and lactic acid was then introduced. After filling the solution and heating to about 100 ° C, the aluminum metal was attacked with hydrogen evolution. The progress of the reaction was observed by determining the aluminum and chloride content of the solution. At an aluminum: chlorine atomic ratio of 3.3 to 1, the reaction was terminated by draining off the solution. The aluminum complex thus obtained was used for the active ingredients described in Examples 4, 5 and 7.

Example 3

The aluminum complex prepared in Example 1 was mixed with hydrochloric acid, water and glycine to obtain the composition shown in Table 1.

Table 1

Example 4

The aluminum complex prepared in Example 2 was mixed with hydrochloric acid and water to obtain the composition shown in Table 2. Table 2

Example 5 The aluminum complex prepared in Example 2 was mixed with hydrochloric acid, water and lactate to obtain the composition shown in Table 3.

Table 3

The three complexes described in the examples were examined with the aid of GPC measurements with regard to their molecular weight distribution. An RP1 system was used as the separation column. HNO ₃ / water was used as the eluent, the change in the refractive index being detected.

The reference substance is commercially available basic aluminum chloride and aluminum chloride hexahydrate.

Basic aluminum chloride shows four striking peaks with a maximum at: Table 4

The monomeric aluminum chloride hexahydrate only shows a peak at 8.1 min in the chromatogram. Polymeric aluminum species therefore move in the exclusion volume of the separation column and are therefore first eluted and detected. To characterize the new active ingredients, the areas of peaks 1-4 were compared. The results are summarized in Table 5:

Table 5

The table clearly shows that the proportions of Al polymer with high and medium molecular weight are significantly reduced in the new active ingredients and at the same time the proportions of Al monomer and Al oligomer increase sharply. The peak maxima show a shift to less in parallel Molecular weights. Table 6

Example 6

The new aluminum complex described in Example 1 was further processed together with zirconium salt to form an antiperspirant mixture.

Table 7: Zirconium-AI complex

First the basic zirconium carbonate was dissolved in hydrochloric acid, glycine was added and the mixture thus obtained was added with stirring to the new antiperspirant Al complex from Example 1.

The combination of active ingredients obtained was examined with the aid of GPC with regard to its molecular weight distribution. An RP1 system was used as the separation column. HNO ₃ / water is used as the eluent, the change in the refractive index being detected. Commercial zirconium-aluminum-glycine tetrachlorohydrate serves as a reference. Table 8: Active ingredient 1 combined with zirconium

Table 8 shows that the new active ingredient complex with the complex ligands according to the invention shows reduced proportions of high polymer, while Al-oligomer and monomer species increase significantly.

Example 7

The new aluminum complex described in Example 2 was used together with

Expand / elaborated zirconium salt to form an antiperspirant mixture.

Table 9: Zirconium-AI complex

First the basic zirconium carbonate was dissolved in hydrochloric acid, glycine was added and the mixture thus obtained was added with stirring to the new antiperspirant Al complex from Example 1. The combination of active ingredients obtained was examined with the aid of GPC with regard to its molecular weight distribution. An RP1 system was used as the separation column. ENT / water was used as the eluent, the change in the refractive index being detected. Commercial zirconium-aluminum-glycine tetrachlorohydrate served as a reference.

Table 10: Active ingredient 2 combined with zirconium

Table 10 shows that the new active ingredient complex with the complex ligands according to the invention shows reduced proportions of high polymer, while Al-oligomer and monomer species increase significantly.

Claims

claims

1. Basic aluminum halide complexes obtained by reacting aluminum metal with hydrohalic acid and an organic acid, either by dissolving the aluminum metal in a mixture of hydrohalic acid and organic acid or by first dissolving the aluminum metal in the hydrohalic acid and then adding the organic acid.

2. Basic aluminum halide complexes according to claim 1, obtained by reaction with hydrochloric acid as hydrohalic acid.

3. Basic aluminum halide complexes according to claim 1, obtained by reaction with a hydroxycarboxylic acid as an organic acid.

4. Basic aluminum halide complexes according to claim 1, obtained by reaction with glycolic acid or lactic acid as the organic acid.

5. Basic aluminum halide according to claim 1, obtained by reaction at temperatures of 20 to 100 ° C.

6. Basic aluminum halide complexes obtained by reacting aluminum metal with a mixture of a hydrohalic acid and an organic acid and then adding a hydrogen halide acid and / or an organic acid.

7. Mixtures of basic aluminum halide complexes according to claim 1 and conventional antiperspirant active ingredients.