EP3768232A1

EP3768232A1 - Method for treating keratin fibres using sulfonated organic binders

Info

Publication number: EP3768232A1
Application number: EP19707794.4A
Authority: EP
Inventors: Alderano Mannozzi
Original assignee: Jean Paul Myne' Srl
Current assignee: Jean Paul Myne' Srl
Priority date: 2018-03-22
Filing date: 2019-02-28
Publication date: 2021-01-27
Also published as: IT201800003878A1; WO2019179745A1

Abstract

This invention concerns treatment of keratins, and in particular of the keratins in human hair and other animal fur. The invention, in particular, concerns a method for improving the esthetic aspect and physical-mechanical characteristic of the keratins through the application on them of organic binders containing at least one sulfonic functional group.

Description

METHOD FOR TREATING KERATIN FIBRES USING SULFONATED ORGANIC

BINDERS

Description

Field of the invention

Background of the invention

According to common knowledge at the current state of the art, keratins are a group of proteins with a fibrous structure and, generally, a high content of sulfur, which are created by living cells as expression of their genetic code (DNA). These proteins form fibrous macro-aggregates such as hair, nails and the surface layers of the skin. Keratins are classified by type as alpha-, beta-, and amorphous.

The structure of keratins, their esthetic, chemical-physical and mechanical characteristics and the techniques for altering their structure to improve the appearance and cosmetic performance are reflected in the state of the art by the documents:

- Boga C. et al.: Curly or smooth? Old and new answers - Household and Personal Care Today: Hair care monographic supplement Vol. 10 (2) - March/ April 2015; - Istrate D.V.: Thesis on Heat Induced denaturation of fibrous hard a-keratins and their reaction with various chemical reagents, 2011;

- Quadflieg J.M.: Thesis on Fundamental properties of afro- american hair as related to their straightening / relaxing behavior, 2003;

- Robbins C.R.: Chemical and Physical Behavior of Human Hair,

2012;

- Tate M.L. et al.: Quantification and prevention of hair damage J.

Soc. Cosmet. Chem., 1993, 44, 347-3 71 TRI/Princeton, Princeton, NJ- USA;

- Wang B.: Keratin: Structure, mechanical properties, occurrence in biological organisms and efforts at bioinspiration, Progress in Materials Science, Elsevier Ltd. - 2016 76 229-318.

From these documents it can be seen that the concentration in natural keratins of amino acids with residual acid (Aspartic Acid and Glutamic Acid) or basic (Lysine, Histidine and Arginine) functional groups is similar, and in some cases greater, than the content in Cysteine and/or Cystine.

In keratins that have undergone treatments of bleaching, waving, dyeing, straightening or relaxing, the concentration of cysteic acid can be as great as or even greater than the concentration of Cysteine.

On the other hand, in keratins that have undergone the above treatments, the concentration of thiolic groups (R-SH) is absolutely negligible (0.01-0.1 % of total amino acids) except in the case of waving where, only in the reduction stage with thioglycolates or other substances with suitable redox potential, high concentrations of thiolic groups are formed. These, however, in the subsequent stage of treatment, are re- oxidated to disulfide bonds by oxidants such as hydrogen peroxide, sodium bromate or the like.

As examples of the state of the art serving for transitory conditioning of the keratins and their fibers documents

W02016100634 A2 and WO2016074986 A1 can be indicated.

The document W02016100634 A2 discloses a composition for hair conditioning inclusive of one or more materials useful for improving the fibrous properties of the hair. In particular, the composition underlying the treatment proposed by document

W02016100634 A2 has the scope of re-integrating the natural lipids that have an important role in the structure of the hair, where they bind the proteins that are an integral part of the cuticular membrane/outer layer of the hair.

Document WO2016074986 A1 discloses a composition to be used as a shampoo or conditioner that untangles the hair making it easier to comb. In particular, the composition proposed calls for the use of hydrophilic solubilizing substances, cationic and surfactant polymers, excluding the use of hydrophobic substances such as natural/synthetic oils and/or silicones.

Permanent alteration of the keratin structure was performed as long ago as 1938, applying the procedure discovered by Arnold F. Willatt, which uses reducing substances containing thiolic functional groups and a basic environment (e.g. thioglycolate of ammonia).

The same method is still widely used for permanent alteration of the keratin structure as known in document US2631965 A.

Vice versa, the primary amine groups in the keratins (deriving from the aminoacids Arginine, Lisine and Histidine) have been - and still are - used to straighten curly hair by application of substances containing aldehyde groups (such as formic, acetic and glutaric aldehyde, etc.) as known in document US3665072 and e US9844500 B2.

Experts in the sector know that formaldehyde, like other aldehydes, react at temperatures in excess of 100°C with the amine groups (R-NH2) of the keratins, forming so-called“methylene bridges” (R-NH-CH2-NH-R) as known in documents US2006104928 A1 and WO2011104282 A2.

Disclosure of the invention

Purpose of this invention is to provide a method for treatment of the keratins capable of:

- protecting the structure of the keratin fibers during aggressive cosmetic treatments (such as coloring, permanent waving, bleaching, straightening, relaxation, etc.);

- repairing and/or improving the structure of keratins damaged by previous cosmetic treatments;

- improving the aspect and physical-mechanical characteristics of keratins damaged by exposure to environmental stresses (e.g. solar radiation, oxidizing atmospheric agents such as ozone, photochemical smog, etc.).

These and other purposes will be achieved with this invention, which concerns a method for the treatment of the keratins with organic binders containing at least one sulfonic functional group. Detailed description of the invention

According to a preferred - but not exclusive - embodiment, this invention concerns a method for the treatment of keratins with organic binders containing one sulfonic functional group. The invention consists of the discovery of the possibility of using, under cosmetically acceptable conditions, a family of organic binders to alter and improve the esthetic aspect and chemical- physical properties of keratins.

Studies have shown, surprisingly, that the treatment of keratin fibers with organic binders containing at least one sulfonic functional group can affect the keratins, especially if degraded by aggressive cosmetic treatments or environmental stress, in a positive way, significantly improving their esthetic aspect and physical-mechanical characteristics.

The binders that have shown they possess these characteristics have the typical chemical structure of the family of sulfonated organic substances.

The organic binders that have been shown to possess these properties are characterized by the chemical structure indicated hereafter (Formula I):

(X)_e— (S0₃H)_n where:

- X can consist of one or more polyfunctional molecules (for example bifunctional, trifunctional, tetrafunctional, etc.) that do not interfere with the reactive properties of the functional binding group (-S0₃H).

The binding functional groups (-SO₃H) can be bound to X at any point of its structure.

- X can be a single atom (for example C, N, O, S), a group of atoms (for example, functional groups such as ketones (-C(=0)-) or methylene of the type (-CH₂)_n-), or even several groups of atoms (for example alkylenic chains -CH₂n-).

- X includes, but is not limited to including, a single atom, such as Hydrogen, Oxygen, Sulfur, Carbon, Boron, Nitrogen, Halogen, or a group of atoms, such as alcoxy, alkyl, alkenyl, cycloalkenyl, aryl, etherocycloalkyl, etheroaryl, formyl, hydroxy, ether, cyan.

- n = number > (greater than or equal to) 1.

- e = number between 1 and 100.

Examples of binding substances containing at least one sulfonic functional group, according to the chemical structure represented by Formula I, are the following sulfonated organic substances: METHANESULFONIC ACID (CAS no. 75-75-2),

PROPANEDISULFONIC ACID (CAS no. 21668-77-9),

1,4 BUTANEDISOLFUNIC ACID (CAS no. 55-98-1).

When these organic binders are brought into contact, under cosmetically acceptable conditions, with keratin fibers (human hair or animal fur) whose esthetic and physical-mechanical characteristics have deteriorated, or which are characterized by a loss of sheen, a frizzy effect, high porosity and loss of tensile strength, they are able to produce surprisingly significant improvements in the esthetic and physical-mechanical characteristics of the keratins, readily observable by an expert in the sector.

These improvements remain effective and perceptible even after repeated washings of the fibers.

These organic binders, with at least one sulfonic group, according to the structure represented by Formula I and the subject of this patent application, are used dissolved or dispersed in a “cosmetically acceptable medium” (meaning by this a mixture of substances commonly used in the manufacture of cosmetic products) in a concentration between 0.1% and 99.9% by weight/weight.

The substances commonly used in the manufacture of cosmetic products are to be understood as those listed in the International Cosmetic Ingredient Dictionary and Handbook Sixteenth Edition 2016 5 volumes, published periodically by the American organization“Personal Care Products Council” 1620 L Street, NW Washington, D.C.).

They are classified in categories including, but not limited to, the following: abrasive, absorbent, anti-agglomerant, anticorrosive, anti-dandruff, defoamer, antimicrobic, antioxidant, anti-perspirant, anti-plaque, antiseborrheic, antistatic, astringent, binder, whitener, buffer, swelling agent, chelator, detergent, cosmetic dye, denaturant, deodorant, depilatory, disentangler, emollient, emulsifier, emulsion stabilizer, film coating agent, fragrance, foamer, gelling agent, hair conditioner, hair dye, hair conditioner, hair color, fixative for hair, waving or straightening agent for hair, moistener, hydrotrope, keratolith, masking agent, moisturizer, nail conditioner, matting agent, oxidizer, pearlescent, fragrance, plastifier, preservative, propellant, reducing agent, filler, freshener, skin conditioner, protective for the skin, soluble smoothing agent, soothing stabilizer, surfactant, tanning agent, tonic, UV absorbent, UV filter, viscosity regulator.

EXAMPLES OF APPLICATION:

Following the surprising effects observed during the stages of research and development of the technique for application of organic binders that is the subject of this patent application, tests of their application to human keratins (hair) were carried out as described in the examples hereafter.

Example 1: Comparison between the traditional permanent wave and a permanent wave performed using the sulfonated organic binder methanesulfonic acid (CAS no. 75-75-2).

Samples of hair were obtained from a human subject and cut in two locks of about 1 cm width and weight of about 5 grams.

Commercial kit for permanents: the kit used, produced by Cosmec srl of Milan (Italy), contained in step 1 the reducing substances based on thioglycolates of ammonium dispersed in a“cosmetically acceptable medium” and as oxidizing agent (step 2) hydrogen peroxide, also dispersed in a“cosmetically acceptable medium”. Organic binder used: methanesulfonic acid (CAS no. 75-75-2) dissolved in a“cosmetically acceptable medium”.

The cosmetically acceptable medium containing the organic binding substance with other substances commonly used in cosmetics, is defined as the“binding mixture”.

The “binding mixture” used had the composition indicated in Table (I) hereafter.

TABLE (I)

A second “cosmetically acceptable medium” was likewise prepared, containing all the ingredients listed in Table (I) with the exception of the sulfonated organic binder methanesulfonic acid. The locks of hair were washed with shampoo, dried with a towel and then wound around a curler for permanents (a tool with which persons expert in the sector is thoroughly familiar).

Step 1 of the commercial kit was applied to the two locks of hair and left in contact for 20 minutes.

The hair was then rinsed with warm water and dried with a towel Method using organic binder

The“binding mixture” detailed in Table (I) was applied on the first lock of hair, mixing 20 grams of binding mixture and 30 grams of step 2. The mixture was then left on the hair for 15 minutes.

The lock of hair was then rinsed with warm water for about 1-2 minutes and unrolled from the curler.

The lock was dehydrated by heating it with a special hair curling iron (with which experts in the sector are familiar) at the temperature of 150°C.

The lock was washed with Keratin Plus shampoo from the

Treasure Jean Paul Myne ® line.

The washing and drying steps were repeated 10 times.

Method without using organic binder

A second lock of hair was treated in the same way described for the first lock of hair, using the mixture detailed in Table (I) without the sulfonated organic binder methanesulfonic acid.

Results

Both permanents exhibited good resistance of the wave produced by the permanent after a first washing and conditioning. After 10 cycles of washing and drying with the same shampoo and conditioner, a marked reduction of the wave compared with the situation obtained after the first washing with shampoo and conditioner was observed.

However, the aspect and consistency of the permanent obtained using the“binding mixture” of Table (I), containing the sulfonated organic binder methanesulfonic acid, exhibited more sheen and better combability than the permanent obtained using the mixture without the sulfonated organic binder methanesulfonic acid.

The lock treated with the binding mixture detailed in Table (I) also displayed better tensile strength than the lock treated with the mixture lacking the sulfonated organic binder methanesulfonic acid.

Example 2: Test of the sheen and consistency of hair after treatment with a “binding mixture” containing the sulfonated organic binder methanesulfonic acid (CAS no. 55-98-1).

Two locks of natural (untreated) black hair were obtained from a person of the Caucasian race.

Organic binder used: 1 ,4-butanedisulfonic acid (CAS no. 55-98-1) dissolved in a“cosmetically acceptable medium”.

The “binding mixture” used had the composition indicated in Table (II) hereafter.

TABLE (II)

A second “cosmetically acceptable medium” was likewise prepared, containing all the ingredients listed in Table (II) with the exception of the sulfonated organic binder methanesulfonic acid.

Both mixtures were blended in a 1:3 ratio with a conditioner (Jean Paul Myne® Ocrys Bandha Conditioner) to make a uniform creamy paste.

Methods

The two locks of hair were washed with Jean Paul Myne® Ocrys Bandha shampoo, then dried with a towel.

The hair was combed using a comb with wide teeth, then using one with fine teeth for 2 minutes.

After combing, the creamy paste containing the binding mixture detailed in Table (II) was applied manually, using a paintbrush, to the lock of hair, which was then combed for about 1 minute.

The sample of hair was left in contact with the creamy paste containing the sulfonated organic binder 1 ,4-butandisulfonic acid for about 15 minutes, then rinsed with water and washed with Jean Paul Myne® Ocrys Bandha Shampoo and Conditioner.

The same hair sample was washed and conditioned five more times with the same shampoo and conditioner.

A second lock of hair was treated the same way described above, however using the second creamy paste containing all the ingredients listed in Table (II) except the sulfonated organic binder 1,4-butanedisulfonic acid. Both locks were dehydrated by heating with a special hair curling iron (with which experts in the sector are familiar) at the temperature of 180°C.

Results

The sample of hair treated with the“binding mixture” containing the sulfonated organic binder 1 ,4-butanedisulfonic acid was softer to the touch than the sample treated with the creamy paste lacking the sulfonated organic binder 1 ,4-butanedisulfonic acid.

The lock treated with the binding mixture detailed in Table (II) also displayed better tensile strength and sheen than the lock treated with the mixture lacking the sulfonated organic binder 1 ,4- butanedisulfonic acid.

The hair sample treated with the“binding mixture” detailed in Table (II) was esthetically“better looking” than the other. The shinier aspect and better consistency remained unchanged after five treatments with shampoo and conditioner.

Example 3: Test of the sheen and consistency of hair after treatment with a “binding mixture” containing the sulfonated organic binder propanedisulfonic acid (CAS no. 21668-77-9). A sample of blonde hair, described as highly porous, kinky and difficult to comb, was obtained from a human subject of the Caucasian race. The sample of hair was divided into two locks of hair weighing about 3 grams each.

Organic binder used: propanedisulfonic acid (CAS no. 21668-77- 9) dissolved in a“cosmetically acceptable medium”.

The cosmetically acceptable medium containing the organic binding substance with other substances commonly used in cosmetics, is defined as the“binding mixture”. The “binding mixture” used had the composition indicated in Table (III) hereafter.

TABLE (III)

A second “cosmetically acceptable medium” was likewise prepared, containing all the ingredients listed in Table (III) with the exception of the sulfonated organic binder propanedisulfonic acid.

The two mixtures were then mixed with Jean Paul Myne ® Ashana Conditioner in a ratio of 1:2 to obtain a uniform creamy paste containing the above ingredients dispersed in it.

Methods

Both locks of blonde hair were washed with Jean Paul Myne ® Ashana shampoo and dried with a towel. The hair was combed using a comb with wide teeth, followed by combing with fine tooth comb for 5 minutes.

On one of the two locks, about 5 grams of the creamy paste containing the sulfonated organic binder propanedisulfonic acid were applied manually using a brush.

The lock was then combed for about 2 minutes.

The sample of hair was left in contact with the“binding mixture” detailed in Table (III) for about 10 minutes. The hair was then treated again with about 5 grams of the“binding mixture” of Table (PI).

The hair sample was combed for about 10 seconds and left undisturbed for another 5 minutes.

The hair sample was then rinsed with water and subsequently washed with Jean Paul Myne® Ashana shampoo and conditioner and dried with a hand-held hairdryer.

After the initial examination, the sample was washed and conditioned two more times with the same shampoo and conditioner.

A second lock of hair was treated the same way described above, however using the second creamy paste containing all the ingredients listed in Table (III) except the sulfonated organic binder propanedisulfonic acid.

The two locks, after being dried with a hand-held hairdryer, were dehydrated by heating with a special flat iron (with which experts in the sector are familiar) at the temperature of 180°C.

Results

The sample of hair treated with the“binding mixture” containing the sulfonated organic binder propanedisulfonic acid was softer to the touch than the sample treated with the creamy paste lacking the sulfonated organic binder propanedisulfonic acid.

The lock treated with the binding mixture detailed in Table (III) also displayed significantly greater tensile strength and better sheen than the lock treated with the mixture lacking the sulfonated organic binder propanedisulfonic acid.

The hair sample treated with the“binding mixture” detailed in Table (III) was esthetically“better looking” than the other. The shinier aspect and better consistency remained unchanged after two treatments with shampoo and conditioner.

Example 4: Test of the color retention and consistency of hair after treatment with a“binding mixture” containing the sulfonated organic binder methanesulfonic acid (CAS no. 75-75-2).

Three locks of hair weighing about 5 grams were obtained from a person of the Caucasian race.

Color formulation: commercial kit for the permanent coloring of hair consisting of: Jean Paul Myne® permanent color DOC COLOR (grade#4) + Jean Paul Myne ® bleaching agent DOC

ENZYME 0.3 (hydrogen peroxide 30 volumes).

Organic binder used: methanesulfonic acid (CAS no. 75-75-2) dissolved in a“cosmetically acceptable medium”.

The “binding mixture” used had the composition indicated in Table (IV) hereafter.

TABLE (IV)

A second “cosmetically acceptable medium” was likewise prepared, containing all the ingredients listed in Table (IV) with the exception of the sulfonated organic binder methanesulfonic acid.

Two portions of cosmetic coloring paste were then prepared, consisting of 50 grams of the color kit Jean Paul Myne® + 10 grams of the binding mixture of Table (IV) plus a third portion of cosmetic coloring paste consisting of 50 grams of the color kit Jean Paul Myne® + 10 grams of a “cosmetically acceptable medium” containing all the ingredients listed in Table (IV) except the sulfonated organic binder methanesulfonic acid

Methods

The hair samples were washed with a Jean Paul Myne® Treasure Enhancing shampoo then dried with a towel.

After that, the cosmetic coloring paste without the sulfonated organic binder methanesulfonic acid was applied on one lock of hair, massaging with the fingers to facilitate its absorption by the keratin fibers, and leaving it in contact for 15 minutes.

On the other two locks of hair, the cosmetic coloring paste containing the sulfonated organic binder methanesulfonic acid was applied in the same way, massaging with the fingers to facilitate its absorption by the keratin fibers.

One lock was left in contact with the cosmetic paste for 5 minutes while the other was left in contact with the cosmetic paste for 15 minutes.

After the contact time established, the three locks of hair were rinsed with warm water, then washed with Jean Paul Myne®

Treasure Enhancing Shampoo and Conditioner five times before examining the results.

Results The two locks of hair treated with the“binding mixture” of Table (IV) exhibited better color retention, greater brilliance and less of a kinky effect than the lock treated with the creamy paste lacking the sulfonated organic binder methanesulfonic acid.

The locks treated with the“binding mixture” of Table (IV) had a more“pleasing” esthetic aspect when examined.

The lock of hair in contact with the“binding mixture” of Table (IV) for 15 minutes was significantly shinier than the lock in contact for 5 minutes.

On the whole, the locks treated with the sulfonated organic binder methanesulfonic acid had a significantly shinier aspect and greater tensile strength than the lock treated with the cosmetic mixture lacking the sulfonated organic binder methanesulfonic acid.

Example 5: Comparison between hair treated with a bleaching cosmetic product applied simultaneously with the “binding mixture” containing the sulfonated organic substance butanedisulfonic acid (CAS. No. 55-98-1) and hair treated with the bleaching cosmetic product alone.

Organic binder used: butanedisulfonic acid (CAS no. 55-98-1) dissolved in a “cosmetically acceptable medium”. The cosmetically acceptable medium containing the organic binding substance with other substances commonly used in cosmetics, is defined as the“binding mixture”.

The “binding mixture” used had the composition indicated in Table (V) hereafter.

TABLE (V)

The commercial bleaching kit used was marketed by Jean Paul Myne® and consisted of the following products: DOC OLEODEC

+ DOC ENZYME 0.3.

From the bleaching kit, two 30 grams portions were taken, and the first was mixed with 10 grams of the binding mixture of Table

(V), while the second was mixed with 10 grams of a“cosmetically acceptable medium” containing all the ingredients listed in Table (V) sulfonated organic binder 1,4-butanedisulfonic acid.

Each portion was blended and homogenized to obtain a uniform creamy paste.

For the test, two locks of human hair were used, each weighing 3 grams and about 20 cm long, from a person of the Caucasian race. The hair, which was brown, had been previously colored with a professional hair dye and was kinky, difficult to comb and highly porous.

The first lock was bleached with the creamy paste containing the sulfonated organic binder 1,4-butanedisulfonic acid, applied with an applicator brush to the hair resting on a sheet of aluminum foil. The foil sheet was then folded around the lock leaving it in contact with the creamy paste for 30 minutes. The lock was then washed with Jean Paul Myne® OCRYS Bandha and rinsed with warm water for 2 minutes.

The second lock was bleached with the portion of bleaching paste without the sulfonated organic binder 1,4-butanedisulfonic acid. Here too, the bleaching paste was applied with an applicator brush on the hair resting on a sheet of aluminum foil. The foil sheet was then folded around the lock leaving it in contact with the creamy paste for 30 minutes.

Both locks were then washed with Jean Paul Myne® OCRYS

Bandha and rinsed with warm water for 2 minutes.

Results

A marked difference was observed between the quality of the lock treated with the“binding mixture” of Table (V) and the lock treated with the cosmetic paste without the sulfonated organic binder 1 ,4-butanedisulfonic acid.

The lock treated with the binding mixture of Table (V) was softer to the touch, not as kinky, shinier and brilliant, giving an evident impression of greater hydration than the other.

Both samples were washed and conditioned five more times with the same shampoo and conditioner.

After five washings, the benefits obtained on the lock treated with the“binding mixture” containing the sulfonated organic binder 1,4-butanedisulfonic acid were even more obvious in comparison with the other.

The lock treated with the bleaching kit mixed with the“binding mixture” detailed in Table (V) displayed better tensile strength and sheen than the lock treated with the commercial bleaching kit lacking the sulfonated organic binder 1 ,4-butanedisulfonic acid. Except as defined otherwise, all the technical and scientific terms used here have the same meanings commonly understood by an expert in the sector to which the invention described pertains (cosmetic arts). The publications and patent documents mentioned in this document are specifically incorporated as references.

Experts in the sector will recognize, or are able to recognize using the normal technique for application of cosmetic products, many equivalent situations to the specific embodiments of the invention described in the above reports (the examples are not exhaustive). These equivalent applications will be included in the claims attached.

The materials and dimensions of the finding as described above and claimed hereafter, can be of any kind or type depending on needs. Moreover, all the details are replaceable with others that are technically equivalent, without thereby exceeding the scope of protection of this patent application.

Claims

1. Method for improvement of the esthetic aspect and physical- mechanical characteristics of keratins, characterized by the application on the keratins of at least one organic binder containing at least one sulfonic functional group and having a chemical structure corresponding to the following scheme

(X)e-(S0₃H)_n where:

- X consists of one or more polyfunctional molecules (for example bifunctional, trifunctional, tetrafunctional, etc.) that do not interfere with the reactive properties of the functional binding group (-S0₃H), and the binding functional groups (-SO₃H) can be bound to X at any point of its structure.

- X consists of a single atom (for example C, N, O, S), a group of atoms (for example, functional groups such as ketones (-C(=0)-) or methylene of the type (-CH₂)_n-), or even several groups of atoms (for example alkylenic chains -CH₂n-).

- n = number > (greater than or equal to) 1.

- e = number between 1 and 100.

2. Method for the treatment of keratins according to claim 1, characterized by the application on the keratins of methanesulfonic acid (CAS no. 75-75-2) in a concentration between 0.1 % and 99.9 %.

3. Method for the treatment of keratins according to claim 1, characterized by the application on the keratins of propanedisulfonic acid (CAS no. 21668-77-9) in a concentration between 0.1 % and 99.9 %.

4. Method for the treatment of keratins according to claim 1, characterized by the application on the keratins of 1,4- butanedisulfonic acid (CAS no. 55-98-1) in a concentration between 0.1 % and 99.9 %.

5. Method for the treatment of keratins according to claim 1, characterized by the application to the keratins of at least one of the substances indicated in claims 1, 2, 3 and 4, dissolved or dispersed in a cosmetically acceptable medium.

6. Method for the treatment of keratins according to claims 1, 2, 3, 4 and 5 characterized in that the organic binders are dissolved in a cosmetically acceptable medium at a concentration between 0.1% and 99.9 % (weight/weight).

7. Method for the treatment of keratins according to claims 1, 2, 3, 4, 5 and 6, characterized in that the sulfonated organic binders are used according to the procedure consisting of the following steps:

7. a: application on the keratins of one of the cosmetically acceptable solutions containing the sulfonated organic binders according to claims 1, 2, 3, 4, 5 and 6;

7.b: maintenance in contact of the cosmetically acceptable solutions containing the sulfonated organic binders according to claims 1, 2, 3, 4, 5 and 6 with the keratins for a period of time between 1 minute and 60 minutes; rinsing of the keratins with water;

rying of the keratins using heated air blowers commonly used in the cosmetic art (hairdryer);

ossible exposure of the keratins to a heat source that warms to a temperature between 50 and 250°C through the use of tools of common use in the cosmetic arts (curling irons or heating tongs).