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Publication numberUS3349000 A
Publication typeGrant
Publication dateOct 24, 1967
Filing dateJan 21, 1964
Priority dateJan 24, 1963
Also published asDE1467953A1
Publication numberUS 3349000 A, US 3349000A, US-A-3349000, US3349000 A, US3349000A
InventorsJoos Bernhard
Original AssigneeJoos Bernhard
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Process for treating human nails and hair with dimethylol thiourea compositions
US 3349000 A
Abstract  available in
Previous page
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Claims  available in
Description  (OCR text may contain errors)

Get. 24, 1967 Y B.JOOS 3,349,000


Zurich, Switzerland Filed Jan. 21, 1964, Ser. No. 339,271

Claims priority, application Switzerland, Jan. 24, 1963, 855/ 63 3 Claims. (Cl. 167S5) The present invention relates to a cosmetic process wherein solid keratinous material such as hair and nails are .given improved strength and elasticity. More particularly, the present invention relates to a process for improving strength and elasticity of said material by treating it with a solution or suspension of reaction products of thiourea and aldehyde. When applied to human fingernails or toenails, the process of the present invention improves resistance of the nails to cracking, splitting, laminating or similar damage. Human hair treated by the process of the present invention ha improved elasticity and is better dressable. By the present process the loss of original properties of the hair, especially those related to the elasticity, which were damaged by preceding treatments such as bleaching, permanent wave, dyeing or the like is partially compensated; further naturally weak hair may be strengthened by said process. The process of the present invention further makes use of compositions which are absolutely free of substances which may produce undesirable side effects.

It is already known that strength and elasticity of keratinous materials may be increased by treatment with aldehydes. The use of aldehydes in the cosmetic field however suffers from the disadvantage that besides the aforementioned effects the aldehydes produce undesirable sideeffects, such as inflammation, hardening and/ or formation of horn on adjacent skin areas. Apart from this, the free aldehydes prove to have a rather dangerous toxic effect, especially on the nerve cells of the skin and the capillaries.

The present invention is based on the discovery that products obtained from the reaction of formaldehyde with thiourea impart to native keratins higher elasticity and strength than do the free aldehydes and moreover do not produce any undesirable side effects. In other words, the invention is based on a process of strengthening keratinous material, especially nails and hair, wherein the keratinous material is treated with a dilute organic or aqueous dispersion or solution of dimethylol thiourea. The principal effect of the dimethylol thiourea applied to the keratinous material apparently is to modify the surface (a) by reaction with free amino groups of the keratinous material, and (b) by polymerization of the dimethylol thiourea layer so produced on the keratin. As is known, aldehydes impart to keratins strength and improved elasticity which properties obviously result from reaction of the aldehydes with amino groups of the keratins. When e.g. formaldehyde is used methylene bridges are formed. In the same manner with dimethylol thiourea methylene bridges between one methylol group of said substances and the amino groups of the keratins are built.

Furthermore, the aforementioned products are capable of polymerizing. After reaction with the keratins polymerization occurs and thereby a film is formed which is tightly anchored to the keratins, the film imparting to the nails, hair, fibres or furs coated therewith useful novel properties both from the mechanical as well as chemical point of view. The film effects an increase in elasticity, plasticity and tensile strength; it is practically insoluble in water and various organic solvents, which is of utmost importance for the purpose it is to serve. The polymerization and the film formation, occurring upon the application can be supported by adding polymerization catalysts that are compatible with the skin. Weak acids and salts, such as phosphoric acid, lactic acid, acetic acid, ammonium chloride, aluminum chloride are particularly suitable for the purpose.

The process according to the present invention is preferably carried out by using aqueous solutions. Its effectiveness can be objectively proved, e.g. by testing single hairs for their elasticity.

Dimethylolthiourea as used for the process according to the invention is in general prepared from thiourea and formaldehyde; the preparation may proceed e.g. in the following manner:

Thiourea is dissolved in water and formaldehyde is added in the form of an aqueous 40% solution. While continuously stirring the solution concentrated (20%) soda lye is added until the pH value reaches 8.5. After cooling in the refrigerator for several days crystals of dimethylol-thiourea precipitate from the solution; they are filtered by means of suction, washed with an aqueous thiourea solution, and dried. Dimethylolurea in cold water yields solutions of about 15% Concentration.

The final composition used for the process of the invention may be obtained as follows:

In a first container 5 to 15 parts by weight of dimethylolurea or dimethylolthiourea are dissolved in 80 parts by volume of warm water at 50 to 60 C. In another container 1 to 10 parts by weight of primary sodium phosphate or 0.2 to 2 parts by weight of an organic acid compatible with the skin, especially of an organic acid normally present in living organisms, such as e.g. lactic acid, citric acid, glycerophosphoric acid, or the like, are dissolved in 20 parts by volume of water. (Here as in the subsequent examples parts by weight are related to parts by volume a grams to milliliters.) While stirring the second solution is added to the first one so that a clear, transparent solution develops, the pH value of which is adjusted, if need be, to 2-6 with diluted soda lye. The compositions for carrying out the process of the invention generally contain about 1 to 15% by weight, preferably 5 to 15% by weight of thiourea. The acid content may be about 0.2 to 2% by weight, while bases, salts and buffer substances are added in the proportions necessary to obtain the desired pH value. The solution thus obtained may be used for the treatment of nails.

A similar solution may be employed for hair; preferably it contains a thickener, e.g., 1-5 percent by weight of polyvinylpyrrolidone and/ or 0.2-2 percent by weight of polyethyleneglycol, or other thickeners known per se.

In either solution the water can be replaced partly or wholly by organic solvents, such as, e.g., ethyl alcohol, dioxane, dioxolane, or mixtures thereof. The solutions or dispersions of the invention contain no free aldehydes.

Instead of treatment with acidic solutions the process of the invention may be practiced by first applying a weak acid to the keratinous substrate and then wetting with a neutral or even slightly basic solution of dimethylol thiourea. Further it is possible to start the process with wetting the surface of the keratinous material with the neutral or slightly basic solution of dimethylol thiourea and then applying the weak acid to the so-treated surface.

In treating hair or nails with such solutions the following effects are obtained:

Solutions of dimethylol thiourea, such as specified in the following examples, react with the keratinous substances of the nails or -hair so that new combinations of dimethylol thiourea with keratin develop. The compounds thus obtained are in particular capable of polymerizing with one another producing at the same time film-forming polymers that are insoluble in water.

The nature of the chemical process involved can be investigated by color reactions; with keratin treated according to the invention the Ninhydrin test is negative. Nails or hair treated in the manner of the invention give no color with Ninhydrin thus indicating that free keratin and free amino groups are no longer present.

The treated and thus modified keratins display an increased elasticity, plasticity and resistance to breaking without losing any of their usual desirable properties. Such improvement can be specifically tested by subjecting untreated hair as well as hair that has been treated by the process according to this invention to a recordable stressgit will be seen after the treatment of the hair by the method herein described that elasticity, plasticity and resistance to breaking have been increased. Results of corresponding tests are given in the annexed diagrams.

Merhod.A hair is placed between two clamps and loaded by continuously increasing weights whereby the exerted stress however remains beyond the value leading to break (Sadamel Microtester, Type Mi 44, No. C 620,- 634). Then the hair reversely is unloaded in the same way. The elongation in case of increasing and decreasing load is recorded diagrammatically. From the area included by the two curves (increasing and decreasing load versus elongation) and the inclination of the curves differences in elasticity and strength of the hair may be taken.

Test No. 1.A normal untreated hair of a woman was cut into identical pieces of 3 cm. length each. The diameters of the individual test pieces were compared and samples of identical diameter were used for the test. One untreated piece was tested in the above manner and curve 1 of FIG. 1 was obtained.

A second sample was immersed in a 10% aqueous solution of dimethylol thiourea (pH value 5) for minutes and dried at a temperature of 30 to 40 C. for to minutes. Thereafter this sample was subjected to the same test as the untreated hair; the result is given by curve 2 of FIG. 1.

Test N0. 2.--As described in Test No. 1 the properties of an untreated sample of hair were investigated and recorded (FIG. 2, curve 1) A second sample was immersed into a 8% solution of dimethylol thiourea in aqueous ethanol (pH=5) for 10 minutes. After drying the hair was tested and curve 2 of FIG. 2 was obtained.

From comparison of the curves obtained with treated and untreated hair it is evidentthat the treatment with dimethylolthiourea yields a significant improvement of strength and elasticity of the hair.

Repeated treatment of fingernails or toenailswith the solutions as specified will result in a strengthening of the nails which, nevertheless, retain their natural. elasticity, and any previous tendency of the nails to crack will be eliminated or at least decreased.

The presentinvention will be further illustrated by the following examples. In these examples parts by weight are related to parts by volume like grams to milliliters.

Example 1 A solution prepared from 2 parts by weight of dimethylol thiourea, 0.2 part by weight of glycerophosphoric acid, 20 parts by weight of33% ethanol and 0.7 part by volume of 1 N aqueous NaOH and having a pH value of 5 is applied to finger nails that are free from any nail polish.

A it The solution dries within a few minutes, whereupon the nails if desired may be enamelled. The nails so treated exhibit improved resistance to cracking and splitting.

Example 2 A solution producing the same etfects like that of Example 1 is prepared from the 2 parts by weight of dimethylol urea, 0.2 part by weight of glycerophosphoric acid, 6.5 parts by weight of ethyl alcohol (96%), 13.5 parts by weight of dioxolane and 0.7 part by volume of 1 N aqueous NaOH. It is applied to finger or toe nails in the same manner as described in Example 1.

Example 3 A composition of matter to be used as nail hardening composition is obtained as follows:

2 parts by weight of dimethylol thiourea, 0.2 part by weight of glycerophosphoric acid, 6.5 parts by weight of ethyl alcohol (96%) and 13.5 parts by weight of dioxane are mixed and the mixture is adjusted to a pH value of 4 by addition of 1 N aqueous sodium hydroxide to yield an effective nail strengthening composition.

Example 4 About 20-30 milliliters of a solution prepared from 15 parts by weight of dimethylol thiourea, 150 parts by weight of aqueous ethyl alcohol (15% ethanol) and 7.5 parts by weight of glycerophosphoric acid, the total mixture having a pH value of value of 2.7, are applied to the head of a woman. and rubbed into the hair after. shampooing. Before application of the aforementioned.

composition the hair had been dried in the best possible way by means of a towel. Now the hair is set and dried by means of a drying apparatus at the usual temperature of about 40 C. for 30 to 45 minutes. Thereafter the hair is dressed as usual. The dressing so obtained can be fairly maintained. After repeated treatment the hair becomes very elastic and stronger.

Example 5 A composition of matter which may be used as described in Example 4 is obtained from the following constituents: 7.5 parts by weight of dimethylol urea, 150 parts by weight of aqueous, ethyl alcohol (15% ethanol), 7.5 parts by weight of glycerophosphoric acid; The pH value of the resulting solution is 2.7.

Example 6 A further treating solution which may be used in the process of the present invention is obtained by mixing about 1 to about 15% by weight of the. total composition.

of dimethylol thiourea, about 0.2 to about 2% by weight of an acidic compound selected from the group consisting of phosphoric acid, lactic acid, citric acid, acetic acid,

' glycerophosphoric acid and acid salts thereof, and a liquid diluent.

2. A process according to claim 1 wherein the fluid composition contains about 5 to 15 by weight of the total composition of dimethylol thiourea.

3. A processaccording to claim 1 wherein the liquid diluent is a member selected from the group consisting of water, alcohols, dioxane, dioxolane and mixtures thereof.

(References on following page) References Cited UNITED STATES PATENTS Schwarzkopf 16787 Brown 16787 5 Maxwell 16785 X Habicht et a1. 16787 Cassidy 16787 6 FOREIGN PATENTS 1,015,804 8/1952 France.

ALBERT T. MEYERS, Primary Examiner.


VERA C. CLARKE, Assistant Examiner.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US1811809 *Jul 17, 1930Jun 23, 1931Kurt SchwarzkopfPulverulent preparation for the production of alpha rinsing liquid for the after treatment of washed animal fibers, woolen or silken fabrics, and especially the hair of the head
US2084127 *Feb 7, 1933Jun 15, 1937Frederics Inc EHair rinse
US2407376 *Oct 31, 1942Sep 10, 1946American Cyanamid CoColloidally dispersed dimethylol urea resins
US3149042 *Jun 24, 1960Sep 15, 1964Colgate Palmolive CoHair preparations
US3208910 *Oct 23, 1961Sep 28, 1965Eugene Cassidy HarryZirconium acetate hair treating composition and process of using same
FR1015804A * Title not available
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3642429 *Oct 23, 1968Feb 15, 1972OrealCosmetic composition for treating hair
US3650280 *Dec 3, 1969Mar 21, 1972Roberts DavidCosmetic treatment of hair with thiourea or urea and glyoxal
US3676546 *Jul 24, 1969Jul 11, 1972OrealNeutralizing compositions for permanent wave operation
US3736944 *Dec 17, 1971Jun 5, 1973OrealCompositions and procedures for effecting a permanent wave or set in the hair
US3773056 *Mar 5, 1971Nov 20, 1973OrealCompositions and methods of improving the quality of human hair with stable methylol compounds
US3920400 *Feb 5, 1974Nov 18, 1975Boehringer Mannheim GmbhUric acid standard solution
US4294852 *Aug 21, 1975Oct 13, 1981Johnson & JohnsonSkin treating compositions
US4363796 *Dec 5, 1978Dec 14, 1982Societe Anonyme Dite: L'orealCosmetic compositions for hardening soft brittle nails
US4547363 *Jun 1, 1982Oct 15, 1985Bernhard JoosPreparation for strengthening, particularly hardening, living finger nails
US5993837 *Oct 13, 1998Nov 30, 1999Revlon Consumer ProductsCompositions for application to keratinous substrates and a method for strengthening such substrates
US6403063Jul 26, 2000Jun 11, 2002Kenneth I. SawyerMethod of treating nail fungus
U.S. Classification424/61, 424/70.5, 8/127.6
International ClassificationA61Q15/00, A61K8/49, A61Q5/00, A61Q3/00
Cooperative ClassificationA61Q15/00, A61K8/4946, A61Q3/00, A61Q5/06
European ClassificationA61Q5/06, A61Q3/00, A61K8/49F1