U.S. patent application number 11/287292 was filed with the patent office on 2006-06-15 for process for relaxing keratin fibres.
This patent application is currently assigned to L'OREAL. Invention is credited to Xavier Radisson.
Application Number | 20060127337 11/287292 |
Document ID | / |
Family ID | 34950815 |
Filed Date | 2006-06-15 |
United States Patent
Application |
20060127337 |
Kind Code |
A1 |
Radisson; Xavier |
June 15, 2006 |
Process for relaxing keratin fibres
Abstract
The invention relates to a process for relaxing keratin fibres
by applying to the keratin fibres a relaxing composition containing
at least one denaturing agent with a molecular mass of greater than
18.1 g/mol, present in a molar concentration of between 1M and 8M,
and raising the temperature of the keratin fibres to a temperature
of between 110 and 250.degree. C.
Inventors: |
Radisson; Xavier; (Paris,
FR) |
Correspondence
Address: |
OBLON, SPIVAK, MCCLELLAND, MAIER & NEUSTADT, P.C.
1940 DUKE STREET
ALEXANDRIA
VA
22314
US
|
Assignee: |
L'OREAL
Paris
FR
|
Family ID: |
34950815 |
Appl. No.: |
11/287292 |
Filed: |
November 28, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60646616 |
Jan 26, 2005 |
|
|
|
Current U.S.
Class: |
424/70.2 |
Current CPC
Class: |
A61K 8/43 20130101; A61K
8/42 20130101; A61Q 5/04 20130101; A61K 8/49 20130101 |
Class at
Publication: |
424/070.2 |
International
Class: |
A61K 8/18 20060101
A61K008/18 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 26, 2004 |
FR |
04 52775 |
Claims
1. A process for relaxing keratin fibres comprising: (i) applying
to the keratin fibres a relaxing composition comprising at least
one denaturing agent with a molecular mass of greater than 18.1
g/mol, present in a molar concentration of between 1M and 8M, to
provide treated keratin fibers, and (ii) raising the temperature of
the treated keratin fibres to a temperature of between 110 and
250.degree. C.
2. The process according to claim 1, wherein the relaxing
composition comprises between 2M and 8M of the said denaturing
agent.
3. The process according to claim 1, wherein the temperature is
raised to a temperature of between 120.degree. C. and 220.degree.
C.
4. The process according to claim 1, wherein the molar mass of the
denaturing agent is between 40 and 600 g/mol.
5. The process according to claim 1, wherein the composition is
applied to wet keratin fibres.
6. The process according to claim 1, wherein the treated fibres are
partially predried prior to raising the temperature of the treated
keratin fibres.
7. The process according to claim 1, wherein the relaxing
composition comprises at least one protein-denaturing agent
selected from ureas, guanidines, aromatic monohydroxylated,
dihydroxylated, trihydroxylated or polyhydroxylated derivatives,
carboxylic acids and derivatives thereof, amino acids, alcohols,
amine oxides, surfactants containing sugar, choline, deoxycholine
or polyethylene glycol units, metal salts and sulfamides.
8. The process according to claim 1, wherein the composition
comprises urea.
9. The process according to claim 1, wherein the composition
comprises at least one compound that corresponds to formula (I):
##STR6## in which: R1, R2, R3 and R4 represent, independently: (v)
a hydrogen atom, or (vi) a linear or branched lower C1-C4 alkyl or
alkenyl radical, optionally substituted with a radical chosen from:
hydroxyl, amino, dimethylamino, carboxyl or carboxamide or
N-methylcarboxamide when R1, R2 and R3 represent a hydrogen atom,
R4 may also denote a radical chosen from the following:
carboxamide; methoxy; ethoxy; 1,2,4-tri-azolyl; cyclopentyl;
methoxycarbonyl; ethoxycarbonyl; CO--CH.dbd.CH--COOH; phenyl
optionally substituted with a chlorine atom or a hydroxyl radical;
benzyl; or 2,5-dioxo-4-imidazolidinyl when R1 and R3 represent a
hydrogen atom, R2 may also represent a hydrogen atom or a methyl or
ethyl radical and R4 an acetyl radical when R1=R2=H, R3 and R4 may
also form, with the nitrogen atom that bears them, a piperidine or
3-methylpyrazole or 3,5-dimethylpyrazole or maleimide ring R1 and
R2, and also R3 and R4, may also form, with the nitrogen atom that
bears them, an imidazole ring.
10. The process according to claim 1, wherein the composition
comprises at least one compound that corresponds to formula (II):
##STR7## in which: R5 and R6 represent, independently of each
other: (iii) a hydrogen atom, or (iv) a linear or branched C1-C4
lower alkyl radical, optionally substituted with a radical chosen
from: hydroxyl, amino, dimethylamino, carboxyl or carboxamide, and
A represents the radicals: CH2-CH2 or CH.dbd.CH or CH2-CO or CO--NH
or CH.dbd.N or CO--CO or CHOH--CHOH or (HOOC)CH--CH or CHOH--CO or
CH2-CH2-CH2 or CH2-NH--CO or CH.dbd.C(CH3)--CO or NH--CO--NH or
CH2-CH2-CO or CH2-N(CH3)--CH2 or NH--CH2-NH or CO--CH(CH3)--CH2 or
CO--CH2-CO or CO--NH--CO or CO--CH(COOH)--CH2 or CO--CH.dbd.C(COOH)
or CO--CH.dbd.C(CH3) or CO--C(NH2).dbd.CH or CO--C(CH3).dbd.N or
CO--CH.dbd.CH or CO--CH.dbd.N or CO--N.dbd.CH.
11. The process according to claim 1, wherein the composition
comprises at least one compound chosen from: urea methylurea
ethylurea propylurea isopropylurea n-butylurea sec-butylurea
isobutylurea tert-butylurea cyclopentylurea 1-ethoxyurea
2-hydroxyethylurea N-(2-hydroxypropyl)urea N-(3-hydroxypropyl)urea
N-(2-dimethylaminopropyl)urea N-(3-dimethylaminopropyl)urea
1-(3-hydroxyphenyl)urea benzylurea N-carbamoylmaleimide biuret
N-carbamoylmaleamic acid 1-piperidinecarboxamide
1,2,4-triazol-4-ylurea hydantoic acid methyl allophanate ethyl
allophanate acetylurea 2-hydroxyethyleneurea
2-(hydroxyethyl)ethyleneurea N-allyl-N'-ethylurea diallylurea
2-chloroethylurea N,N-dimethylurea N,N-diethylurea N,N-dipropylurea
1-cyclopentyl-1-methylurea 1,3-dimethylurea 1,3-diethylurea
1,3-bis(2-hydroxyethyl)urea 1,3-bis(2-hydroxypropyl)urea
1,3-bis(3-hydroxypropyl)urea 1,3-dipropylurea 1-ethyl-3-propylurea
1-sec-butyl-3-methylurea 1-isobutyl-3-methylurea
1-cyclopentyl-3-methylurea N-acetyl-N'-methylurea trimethylurea
1-butyl-3,3-dimethylurea tetramethylurea and benzylurea.
12. The process according to claim 1, wherein the composition
comprises at least one compound chosen from: parabanic acid
1,2-dihydro-3-H-1,2,4-triazol-2-one barbituric acid uracil
1-methyluracil 3-methyluracil 5-methyluracil 1,3-dimethyluracil
5-azauracil 6-azauracil 5-fluorouracil 6-fluorouracil
1,3-dimethyl-5-fluorouracil 5-aminouracil 6-aminouracil
6-amino-1-methyluracil 6-amino-1,3-dimethyluracil 4-chlorouracil
5-chlorouracil 5,6-dihydrouracil 5,6-dihydro-5-methyluracil
2-imidazolidone hydrate 1-methyl-2-imidazolidinone
1,3-dimethyl-2-imidazolidinone 4,5-dihydroxyimidazolidin-2-one
1-(2-hydroxyethyl)-2-imidazolidinone
1-(2-hydroxypropyl)-2-imidazolidinone
1-(3-hydroxypropyl)-2-imidazolidinone
4,5-dihydroxy-1,3-dimethylimidazolidin-2-one
1,3-bis(2-hydroxyethyl)-2-imidazolidinone
2-imidazolidone-4-carboxylic acid 1-(2-aminoethyl)-2-imidazole
4-methyl-1,2,4-triazoline-3,5-dione
2,4-dihydroxy-6-methylpyrimidine
1-amino-4,5-dihydro-1H-tetrazol-5-one hydantoin 1-methylhydantoin
5-methylhydantoin 5,5-dimethylhydantoin 5-ethylhydantoin
5-n-propylhydantoin 5-ethyl-5-methylhydantoin
5-hydroxy-5-methylhydantoin 5-hydroxymethylhydantoin
1-allylhydantoin 1-aminohydantoin hydantoin 5-acetic acid
4-amino-1,2,4-triazolone-3,5-dione
hexahydro-1,2,4,5-tetrazine-3,6-dione
5-methyl-1,3,5-triazinon-2-one 1-methyltetrahydropyrimidin-2-one
2,4-dioxohexahydro-1,3,5-triazine urazole 4-methylurazole orotic
acid dihydroxyorotic acid 2,4,5-trihydroxypyrimidine
2-hydroxy-4-methylpyrimidine 4,5-diamino-2,6-dihydroxypyrimidine
barbituric acid 1,3-dimethylbarbituric acid cyanuric acid
1-methylhexahydropyrimidine-2,4-dione
1,3-dimethyl-3,4,5,6-tetrahydro-2-1H-pyrimidinone
5-(hydroxymethyl-2,4-(1H,3H)-pyrimidinedione
2,4-dihydroxypyrimidine-5-carboxylic acid 6-azathymine
5-methyl-1,3,5-triazinan-2-one N-carbamoylmaleamic acid and alloxan
monohydrate.
13. The process according to claim 1, wherein the composition
comprises at least one compound that corresponds to formula (III)
below: ##STR8## in which: R1, R2, R3, R4 and R5 represent,
independently: (vii) a hydrogen atom, or (viii) a linear or
branched C1-C4 lower alkyl or alkenyl radical, optionally
substituted with one or two radicals chosen from: hydroxyl, amino,
dimethylamino, methoxy, ethoxy, carboxyl, carboxamide,
N-methylcarboxamide or SO.sub.3H when R1, R2, R3 and R4 represent a
hydrogen atom, R5 may also denote a radical chosen from the
following: acetyl; chloroacetyl; carboxamide; methoxy; ethoxy;
1,2,4-triazolyl; cyclopentyl; methoxycarbonyl; ethoxycarbonyl;
CO--CH.dbd.CH--COOH; phenyl optionally substituted with a chlorine
atom or a hydroxyl radical; benzyl; thiazolidone; benzimidazole;
benzoxazole; benzothiazole; or C(.dbd.NH)--NR6R7 in which R6 and R7
denote, independently of each other, a hydrogen atom or a linear or
branched C1-C4 lower alkyl radical, optionally substituted with one
or 2 radicals chosen from: hydroxyl, amino, dimethylamino, carboxyl
and carboxamide; or N-methylcarboxamide; or alternatively a phenyl
radical when R1=R2=R3=H, R4 and R5 may also form, with the nitrogen
atom that bears them, a pyrrolidine, piperidine, pyrazole or
1,2,4-triazole ring, optionally substituted with 1 or 2 radicals
chosen from: hydroxyl, amino and carboxyl when R1=R2=H, and R4=H or
methyl, R3 and R5 may also together form a 5-membered ring
optionally containing an oxo group and the organic or mineral salts
thereof.
14. The process according to claim 1, wherein the composition
comprises at least one compound chosen from: guanidine
hydrochloride guanidine acetate guanidine sulfate guanidine
carbonate guanidine bicarbonate guanidine phosphate guanidine
sulfamate aminoguanidine aminoguanidine hydrochloride
aminoguanidine sulfate aminoguanidine bicarbonate
1,3-diaminoguanidine hydrochloride 1-acetylguanidine
chloroacetylguanidine hydrochloride guanylurea guanylurea phosphate
phenylguanidine carbonate phenylguanidine bicarbonate
1-methylguanidine hydrochloride 1,1-dimethylguanidine hydrochloride
1-ethylguanidine hydrochloride 1,1-diethylguanidine hydrochloride
creatine creatine monohydrate creatinine hydrochloride agmatine
agmatine sulfate guanidinoacetic acid guanidinosuccinic acid
3-guanidinopropionic acid 4-guanidinobutyric acid
5-guanidinovaleric acid beta-N-methylguanidinopropionic acid
N-methylguanidinopropionic acid N-(2-hydroxyethyl)guanidine
N-(3-hydroxypropyl)guanidine biguanide hydrochloride
N-methylbiguanide hydrochloride N-ethylbiguanide hydrochloride
N-propylbiguanide hydrochloride N-butylbiguanide hydrochloride
1,1-dimethylbiguanide hydrochloride 1-phenylbiguanide
1,1,3,3-tetramethylguanidine hydrochloride
2-tert-butyl-1,1,3,3-tetramethylguanidine hydrochloride L-arginine
D-arginine DL-arginine arginic acid
N-amidino-N-(2,3-dihydroxypropyl)glycine N-amidinotaurine
2-imino-1-imidazolidineacetic acid 1-(2,2-diethoxyethyl)guanidine
1H-pyrazole-1-carboxamidine hydrochloride
5-hydroxy-3-methyl-1H-pyrazole-1-carboximidamide
3,5-diamino-1H-1,2,4-triazole-1-carboximidamide hydrochloride
2-guanidone-4-thiazolidone 2-guanidinobenzimidazole
2-guanidinobenzoxazole 2-guanidinobenzothiazole and
pyrrolidinoformamidine hydrochloride.
15. The process according to claim 1, wherein the temperature of
the treated keratin fibres is raised to a temperature of between
110 and 250.degree. C. with a heater.
16. The process according to claim 1, wherein the temperature of
the treated keratin fibres is raised to a temperature of between
110 and 250.degree. C. with a heating means.
17. The process according to claim 15, wherein the temperature of
the treated keratin fibres is raised to a temperature of between
110 and 250.degree. C. with an iron.
18. The process according to claim 1, wherein said composition is
in the form of an aqueous solution or in the form of a thickened
cream.
19. A process comprising raising the temperature of keratin fibres
to a temperature of between 110 and 250.degree. C., wherein said
keratin fibres comprise on at least a part of a surface thereof at
least one denaturing agent with a molecular mass of greater than
18.1 g/mol.
20. The process according to claim 19, wherein the temperature of
the keratin fibres is raised to a temperature of between 110 and
250.degree. C. with an iron.
Description
REFERENCE TO PRIOR APPLICATIONS
[0001] This application claims priority to U.S. provisional
application 60/646,616 filed Jan. 26, 2005, and to French patent
application 0452775 filed Nov. 26, 2004, both incorporated herein
by reference.
FIELD OF THE INVENTION
[0002] The invention relates to a process for relaxing keratin
fibres with heat and at least one denaturing agent.
[0003] Additional advantages and other features of the present
invention will be set forth in part in the description that follows
and in part will become apparent to those having ordinary skill in
the art upon examination of the following or may be learned from
the practice of the present invention. The advantages of the
present invention may be realized and obtained as particularly
pointed out in the appended claims. As will be realized, the
present invention is capable of other and different embodiments,
and its several details are capable of modifications in various
obvious respects, all without departing from the present invention.
The description is to be regarded as illustrative in nature, and
not as restrictive.
BACKGROUND OF THE INVENTION
[0004] Two techniques are used to obtain permanent reshaping of the
hair. They are based on cleavage of the disulfide covalent bonds
present in keratin (cystine):
[0005] the first consists, in a first stage, in performing this
opening of the disulfide bonds using a composition containing a
reducing agent, and then after, preferably, having rinsed the hair,
in reconstituting, in a second stage, the said disulfide bonds by
applying to the hair, that has been placed under tension beforehand
by means of rollers or the like or shaped or smoothed out by other
means, an oxidizing composition also known as a fixer, so as to
give the head of hair the desired shape. This technique makes it
possible either to make the hair wavy or to relax it, uncurl it or
smooth it out;
[0006] the second consists in performing a "lanthionization"
operation, using a composition containing a base belonging to the
hydroxide family. It leads to the replacement of the disulfide
bonds (--CH2-S--S--CH2-) with lanthionine bonds (--CH2-S--CH2-).
This lanthionization operation involves two consecutive chemical
reactions:
[0007] The first reaction consists of a beta-elimination on cystine
brought about by a hydroxide ion, leading to the cleavage of this
bond and to the formation of dehydroalanine. ##STR1##
[0008] The second reaction is a reaction of the dehydroalanine with
a thiol group. Specifically, the double bond of the dehydroalanine
formed is a reactive double bond. It can react with the thiol group
of the cysteine residue that has been released to form a new bond
known as a lanthionine bridge or bond or residue. ##STR2##
[0009] Relative to the first technique using a reducing agent, this
lanthionization technique does not require a fixing step, since the
formation of the lanthionine bridges is irreversible. It is thus
performed in a single step and makes it possible either to make the
hair wavy or to relax it, uncurl it or smooth it out. However, it
is mainly used for relaxing naturally frizzy hair.
[0010] For the first technique, the reducing compositions generally
used for the first step of a permanent-waving or relaxing operation
contain thiols, sulfites or bisulfites as reducing agent. These
agents are generally used in essentially aqueous medium at
concentrations of between 0.5 and 1M to obtain good opening of the
disulfide bonds. Among the thiols, those commonly used are
thioglycolic acid, cysteamine, glyceryl monothioglycolate,
thiolactic acid and cysteine. Thioglycolic acid is particularly
effective for reducing the disulfide bonds of keratin at alkaline
pH, especially in the form of ammonium thioglycolate, and is the
product most widely used in permanent-waving ("hair waving").
However, it has been found that thioglycolic acid must be used in a
sufficiently basic medium (in practice at a pH of between 8.5 and
9.5) if it is desired to obtain curliness of satisfactory
intensity. Besides the drawback of giving off an unpleasant odour
requiring the use of more or less efficient fragrances to mask the
odours, the use of a thiol at alkaline pH also leads to degradation
of the fibre and most particularly to impairment of artificial
colorations.
[0011] Sulfites or bisulfites are mainly used for relaxing. They
have similar drawbacks to thiols, with less efficacy.
[0012] Thiols and sulfites (or bisulfites) also have the drawback
of having poor stability in aqueous solution.
[0013] In general, the durability of the reshaping effects obtained
with thiols and sulfites by reduction of disulfides followed by
fixing is judged to be very much inferior to that which may be
obtained via the lanthionization technique.
[0014] For the second technique, the compositions generally used to
perform the lanthionization contain as base a hydroxide such as
sodium hydroxide, guanidinium hydroxide or lithium hydroxide. These
lanthionization active agents, which allow the disulfide bonds to
be opened via a beta-elimination mechanism, are generally used as a
water-oil emulsion at concentrations of between 0.4 and 0.6M, by
leaving them to act generally for 10 to 15 minutes at room
temperature. Sodium hydroxide remains the agent most widely used.
Guanidinium hydroxide is now the preferred compound for many
compositions. These two hydroxides, sodium hydroxide and
guanidinium hydroxide, are the two main agents used for relaxing or
uncurling naturally frizzy hair. They have several advantages over
ammonium thioglycolate and sulfites, in particular an absence of
unpleasant odour, the fact that only one implementation step is
required (shorter treatment time), and a much greater durability
and efficacy of the reshaping of the hair.
[0015] However, these hydroxides have the major drawback of being
caustic. This causticity affects the scalp by causing irritation,
which may occasionally be severe. This may partially be remedied by
first applying to the scalp a fatty protective cream often referred
to as a "base" or "base cream", the word "base" in this instance
not having the meaning of a basic agent in the chemical sense. When
the protective cream is combined with hydroxide in a single
composition, it is generally known as a "no-base" cream, as opposed
to the above name. This "no-base" technology is preferred.
[0016] The causticity of hydroxides also affects the condition of
the hair by firstly giving it a coarse feel and secondly making it
much more fragile, this fragility possibly going as far as flaking
or even breaking, or even the dissolution of the hair if the
treatment is prolonged. In certain cases, hydroxides also cause
decolorization of the natural colour of the hair.
[0017] Formulations containing sodium hydroxide are generally known
as "lye relaxers" and those not containing it are known as "no-lye
relaxers".
[0018] The main "no-lye" relaxing formulations use guanidinium
hydroxide. Since guanidinium hydroxide is unstable, it is generated
extemporaneously by mixing guanidine carbonate and a source of very
sparingly soluble hydroxide such as calcium hydroxide. The reaction
between these two compounds leads to the formation of guanidinium
hydroxide and calcium carbonate, which precipitates in the
composition. The presence of this precipitate makes the final
rinsing of the hair much more difficult and leaves on the hair and
the scalp mineral particles that give it a coarse feel and an
unattractive appearance resembling dandruff. The recent success of
guanidinium hydroxide ("no-lye") in the face of sodium hydroxide
("lye") appears to arise from better relaxing efficacy and better
skin tolerance. However, these technologies using bases of the
hydroxide family remain very aggressive for the hair and the scalp
and require very strict control of the application time to avoid
excessive irritation and impairment of the hair, which may go as
far as breaking of the hair. This aggressiveness arising from the
causticity of hydroxides is just reason for these hair
lanthionization compositions not being used for permanent-waving
("hair waving"), but being reserved for relaxing ("hair
straightening" or "hair relaxing").
[0019] Furthermore, hydroxides are known to be good agents for
hydrolysing amide functions (cf. for example March's Advanced
Organic Chemistry, 5 ed., Wiley Interscience, New York, "Hydrolysis
of Amides" pages 474 et seq.), which thus lead to cleavage of the
peptide bonds via direct nucleophilic attack. It is thus probable
that the impairments observed on the hair and keratin materials in
the broad sense are largely due to partial hydrolysis of the amide
bonds of keratin.
[0020] There is thus a real need for relaxing compositions that are
markedly less aggressive to the hair.
[0021] Various studies have been conducted in order to overcome the
drawbacks of both reducing agents (first technique) and/or of
hydroxides (second technique).
[0022] Thus, to replace thioglycolic acid, numerous reducing agents
have been proposed, but thioglycolic acid in its ammonium
thioglycolate form remains both the compound of reference and the
compound most widely used in cosmetic formulations, both for
shaping and for straightening.
[0023] It has also been proposed in numerous patents to combine
common reducing agents (thiols, sulfites or bisulfites) with urea
or alkylureas to reduce the irritation and damage caused on the
hair both by shaping and by relaxing. Reference will be made, for
example, to:
[0024] patent application CA 1315204, which describes a composition
containing ammonium thioglycolate (5.5-11.5%) and urea or a
monoalkylurea (1-3%) for shaping the hair,
[0025] patent application U.S. Pat. No. 3,847,165, which describes
a composition containing ammonium thioglycolate (1.2-1.4M) and urea
(2.0-2.7M) for shaping the hair at acidic pH,
[0026] patent application NL 6 410 355, which describes a
composition containing a sulfite (0.8-1.5M) and urea (0.6-3.0M) for
shaping and relaxing the hair,
[0027] patent application JP 2000/229 819, which describes a
composition containing a sulfite or bisulfite (0.5-15%), urea
(0.5-15%) and an alcohol (ethanol and/or isopropanol, 1-30%) for
shaping and relaxing the hair.
[0028] It has also been proposed in numerous patents to combine
hydroxides, serving as lanthionization active agent, with certain
additives generally serving to protect the hair. Mention will be
made, for example, of:
[0029] patent application WO 2002/003 937, which describes a
composition containing C3-C5 monosaccharides,
[0030] patent application WO 2001/064 171, which describes a
composition containing complexing agents,
[0031] U.S. Pat. No. 5,641,477, which describes a composition
containing a hydrogenated starch hydrolysate,
[0032] patent application WO 02/085 317, which describes a
composition containing organic nucleophiles, which react during the
second step with the dehydroalanine formed with hydroxides, to give
new bridges.
[0033] Although all these proposals lead to more or less marked
improvements, they do not make it possible to significantly reduce
the damage caused by the causticity itself of hydroxides.
[0034] As indicated above, the use of reducing agents leads to
mediocre durability for relaxing or uncurling, and the use of
hydroxides, on account of their causticity, limits their use to the
field of relaxing.
SUMMARY OF THE INVENTION
[0035] After extensive studies, it has now been discovered,
entirely surprisingly and unexpectedly, that the hair can be
durably relaxed by combining the action of a denaturing agent and
by heating to a temperature above 110.degree. C. Excellent results
in terms of relaxing, hair cosmetic properties and fibre integrity
are thus obtained.
Definitions
[0036] According to the invention, the term "keratin fibres" means
fibres of human or animal origin such as head hair, body hair, the
eyelashes, wool, angora, cashmere or fur. Although the invention is
not limited to particular keratin fibres, reference will
nevertheless be made more particularly to head hair.
[0037] According to the invention, the term "relaxing" covers the
relaxing, straightening or uncurling, and includes such effects on,
e.g., Caucasian and African hair. According to the invention, the
term "to relax" means to relax, to straighten or to uncurl.
[0038] The term "denaturing agent" includes those compounds
specifically identified as such herein and means an organic or
mineral compound containing both at least one electron-donating
site of basic or nucleophilic nature and at least one
electron-withdrawing site of acidic or electrophilic nature, which
interact with the weak bonds of keratin.
[0039] According to the invention, a denaturing agent is a compound
capable of reducing the optical rotation of a model protein, for
instance bovine serum albumin, by at least 70 and/or 50 at 579 nm,
the measurements being taken after 3 hours of incubation at
37.degree. C., using a polarimeter, as described in Biochemistry 2
(1), 47-57, 1963:
[0040] either in 0.05M pH 7.6 TRIS buffer,
[0041] or in a 5.45M urea solution when the solubility of the
compound is insufficient in 0.05M pH 7.6 TRIS buffer.
[0042] The compound is considered as being a denaturing agent
according to the invention if the reduction in the optical rotation
is at least 70 in 0.05M pH 7.6 TRIS buffer and/or at least
5.degree. in 5.45M urea solution.
[0043] The term "weak bonds of keratin" means all of the
non-covalent bonds, such as:
[0044] the saline bonds resulting from coulombic interactions
between the functional groups present on the side chains of amino
acids, hydrogen bonds, which are established between the amino
acids especially via oxygen and hydrogen atoms,
[0045] hydrophobic bonds resulting from the tendency of the
non-polar chains of amino acids to associate in order to minimize
the contacts with water.
[0046] The term "heating means" is a term invoking 35 U.S.C. 112,
paragraph 6, and is defined as any means for heating keratin fibres
to a temperature of at least 110.degree. C., such as heating irons,
for example flat or round irons, microwave generators, sources of
infrared radiation, etc. The terms "heater" and "heaters" include
all of these examples but are not terms implicating 35 U.S.C. 112,
paragraph 6.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0047] Without being bound by theory, the inventor believes that
there is a combined action, on the keratin fibres, of a denaturing
agent and of the action of a heater or a heating means, which
allows the fibres to be effectively and durably relaxed.
[0048] The Inventor has found that it is possible to overcome the
drawbacks of the prior art and to meet the abovementioned
objectives by performing a process for relaxing keratin fibres
comprising:
[0049] applying to the keratin fibres a relaxing composition
comprising at least one denaturing agent preferably having a
molecular mass (weight) of greater than 18.1 g/mol, present in a
molar concentration of between 1M and 8M in said composition,
and
[0050] raising the temperature of the keratin fibres, for example
using a heater or heating means, to a temperature of between 110
and 250.degree. C.
[0051] These two steps can be accomplished in any order, or
simultaneously. Preferably, they are accomplished in the order
stated above.
[0052] A molar concentration of between 1M and 8M generally
corresponds to a weight concentration of between about 6% and about
80% relative to the total weight of the composition.
[0053] Thus, one subject of the invention is a process for relaxing
keratin fibres comprising:
[0054] applying to the keratin fibres a relaxing composition
comprising at least one denaturing agent with a molecular mass of
greater than 18.1 g/mol, present in a molar concentration of
between 1M and 8M,
[0055] then raising the temperature of the (treated) keratin
fibres, using a heater or heating means, to a temperature of
between 110 and 250.degree. C.
[0056] Optionally, the hair can be dried to some extent after
treatment with the relaxing composition prior to application of
heat to raise the temperature of the keratin fibres, for example by
wiping with a towel, etc. However, it is preferred that the hair
have remaining thereon at least some denaturing agent when heat is
applied so as to obtain the benefits of the present invention.
[0057] Preferably, the relaxing composition comprises between 2M
and 8M of the said denaturing agent; this corresponds to a weight
concentration of between about 12% and about 80%, relative to the
total weight of the composition, of the said denaturing agent.
[0058] Advantageously, the temperature is raised using a heater or
by heating means to a temperature of between 120.degree. C. and
220.degree. C. and more advantageously between 140.degree. C. and
220.degree. C.
[0059] Advantageously, the molar mass of the denaturing agent is
between 40 and 600 g/mol.
[0060] Preferably, the relaxing composition is applied to wet
keratin fibres.
[0061] As noted above, the removal of excess relaxing composition,
for example using a towel, may advantageously be inserted between
the act of applying the relaxing composition and the act of raising
the temperature.
[0062] Preferably, the denaturing agent is chosen from
protein-denaturing agents such as ureas, guanidines, amidines,
urethanes, aromatic monohydroxylated, dihydroxylated,
trihydroxylated or polyhydroxylated derivatives, nitrogen
heterocycles of the imidazole or triazole family, carboxylic acids
and amide and thioamide derivatives thereof, thioureas, amino
acids, alcohols, polyols, amine oxides, surfactants containing
sugar, choline, deoxycholine or polyethylene glycol units, metal
salts and sulfamides.
[0063] The denaturing agent is advantageously a urea or a
guanidine.
[0064] As "urea" that may be used as relaxing active agent, this
term refers to any derivative comprising in its chemical formula a
carbonyl group simply bonded to 2 nitrogen atoms. These ureas are
more particularly selected from the compounds of general formulae
(I) and (II) below: ##STR3##
[0065] in which:
[0066] R1, R2, R3 and R4 represent, independently:
[0067] (i) a hydrogen atom, or
[0068] (ii) a linear or branched lower C1-C4 alkyl or alkenyl
radical, optionally substituted with a radical chosen from:
hydroxyl, amino, dimethylamino, carboxyl or carboxamide or
N-methylcarboxamide.
[0069] When R1, R2 and R3 represent a hydrogen atom, R4 may also
denote a radical chosen from the following: carboxamide; methoxy;
ethoxy; 1,2,4-triazolyl; cyclopentyl; methoxycarbonyl;
ethoxycarbonyl; CO--CH.dbd.CH--COOH; phenyl optionally substituted
with a chlorine atom or a hydroxyl radical; benzyl; or
2,5-dioxo-4-imidazolidinyl.
[0070] When R1 and R3 represent a hydrogen atom, R2 may also
represent a hydrogen atom or a methyl or ethyl radical and R4 an
acetyl radical.
[0071] When R1=R2=H, R3 and R4 may also form, with the nitrogen
atom that bears them, a piperidine or 3-methylpyrazole or
3,5-dimethylpyrazole or maleimide ring.
[0072] Finally, R1 and R2, and also R3 and R4, may also form, with
the nitrogen atom that bears them, an imidazole ring. ##STR4##
[0073] in which:
[0074] R5 and R6 represent, independently of each other:
[0075] (i) a hydrogen atom, or
[0076] (ii) a linear or branched C1-C4 lower alkyl radical,
optionally substituted with a radical chosen from: hydroxyl, amino,
dimethylamino, carboxyl or carboxamide,
[0077] and A represents the radicals: CH2-CH2 or CH.dbd.CH or
CH2-CO or CO--NH or CH.dbd.N or CO--CO or CHOH--CHOH or
(HOOC)CH--CH or CHOH--CO or CH2-CH2-CH2 or CH2-NH--CO or
CH.dbd.C(CH3)--CO or NH--CO--NH or CH2-CH2-CO or CH2-N(CH3)--CH2 or
NH--CH2-NH or CO--CH(CH3)--CH2 or CO--CH2-CO or CO--NH--CO or
CO--CH(COOH)--CH2 or CO--CH.dbd.C(COOH) or CO--CH.dbd.C(CH3) or
CO--C(NH2).dbd.CH or CO--C(CH3).dbd.N or CO--CH.dbd.CH or
CO--CH.dbd.N or CO--N.dbd.CH.
[0078] Among the compounds of formula (I), mention may be made
especially of the following preferred compounds:
[0079] urea
[0080] methylurea
[0081] ethylurea
[0082] propylurea
[0083] isopropylurea
[0084] n-butylurea
[0085] sec-butylurea
[0086] isobutylurea
[0087] tert-butylurea
[0088] cyclopentylurea
[0089] 1-ethoxyurea
[0090] 2-hydroxyethylurea
[0091] N-(2-hydroxypropyl)urea
[0092] N-(3-hydroxypropyl)urea
[0093] N-(2-dimethylaminopropyl)urea
[0094] N-(3-dimethylaminopropyl)urea
[0095] 1-(3-hydroxyphenyl)urea
[0096] benzylurea
[0097] N-carbamoylmaleimide
[0098] biuret
[0099] N-carbamoylmaleamic acid
[0100] 1-piperidinecarboxamide
[0101] 1,2,4-triazol-4-ylurea
[0102] hydantoic acid
[0103] methyl allophanate
[0104] ethyl allophanate
[0105] acetylurea
[0106] 2-hydroxyethyleneurea
[0107] 2-(hydroxyethyl)ethyleneurea
[0108] N-allyl-N'-ethylurea
[0109] diallylurea
[0110] 2-chloroethylurea
[0111] N,N-dimethylurea
[0112] N,N-diethylurea
[0113] N,N-dipropylurea
[0114] 1-cyclopentyl-1-methylurea
[0115] 1,3-dimethylurea
[0116] 1,3-diethylurea
[0117] 1,3-bis(2-hydroxyethyl)urea
[0118] 1,3-bis(2-hydroxypropyl)urea
[0119] 1,3-bis(3-hydroxypropyl)urea
[0120] 1,3-dipropylurea
[0121] 1-ethyl-3-propylurea
[0122] 1-sec-butyl-3-methylurea
[0123] 1-isobutyl-3-methylurea
[0124] 1-cyclopentyl-3-methylurea
[0125] N-acetyl-N'-methylurea
[0126] trimethylurea
[0127] 1-butyl-3,3-dimethylurea
[0128] tetramethylurea
[0129] benzylurea
[0130] Among the compounds of formula (II), mention may be made
especially of the following preferred compounds:
[0131] parabanic acid
[0132] 1,2-dihydro-3-H-1,2,4-triazol-2-one
[0133] barbituric acid
[0134] uracil
[0135] 1-methyluracil
[0136] 3-methyluracil
[0137] 5-methyluracil
[0138] 1,3-dimethyluracil
[0139] 5-azauracil
[0140] 6-azauracil
[0141] 5-fluorouracil
[0142] 6-fluorouracil
[0143] 1,3-dimethyl-5-fluorouracil
[0144] 5-aminouracil
[0145] 6-aminouracil
[0146] 6-amino-1-methyluracil
[0147] 6-amino-1,3-dimethyluracil
[0148] 4-chlorouracil
[0149] 5-chlorouracil
[0150] 5,6-dihydrouracil
[0151] 5,6-dihydro-5-methyluracil
[0152] 2-imidazolidone hydrate
[0153] 1-methyl-2-imidazolidinone
[0154] 1,3-dimethyl-2-imidazolidinone
[0155] 4,5-dihydroxyimidazolidin-2-one
[0156] 1-(2-hydroxyethyl)-2-imidazolidinone
[0157] 1-(2-hydroxypropyl)-2-imidazolidinone
[0158] 1-(3-hydroxypropyl)-2-imidazolidinone
[0159] 4,5-dihydroxy-1,3-dimethylimidazolidin-2-one
[0160] 1,3-bis(2-hydroxyethyl)-2-imidazolidinone
[0161] 2-imidazolidone-4-carboxylic acid
[0162] 1-(2-aminoethyl)-2-imidazole
[0163] 4-methyl-1,2,4-triazoline-3,5-dione
[0164] 2,4-dihydroxy-6-methylpyrimidine
[0165] 1-amino-4,5-dihydro-1H-tetrazol-5-one
[0166] hydantoin
[0167] 1-methylhydantoin
[0168] 5-methylhydantoin
[0169] 5,5-dimethylhydantoin
[0170] 5-ethylhydantoin
[0171] 5-n-propylhydantoin
[0172] 5-ethyl-5-methylhydantoin
[0173] 5-hydroxy-5-methylhydantoin
[0174] 5-hydroxymethylhydantoin
[0175] 1-allylhydantoin
[0176] 1-aminohydantoin
[0177] hydantoin 5-acetic acid
[0178] 4-amino-1,2,4-triazolone-3,5-dione
[0179] hexahydro-1,2,4,5-tetrazine-3,6-dione
[0180] 5-methyl-1,3,5-triazinon-2-one
[0181] 1-methyltetrahydropyrimidin-2-one
[0182] 2,4-dioxohexahydro-1,3,5-triazine
[0183] urazole
[0184] 4-methylurazole
[0185] orotic acid
[0186] dihydroxyorotic acid
[0187] 2,4,5-trihydroxypyrimidine
[0188] 2-hydroxy-4-methylpyrimidine
[0189] 4,5-diamino-2,6-dihydroxypyrimidine
[0190] barbituric acid
[0191] 1,3-dimethylbarbituric acid
[0192] cyanuric acid
[0193] 1-methylhexahydropyrimidine-2,4-dione
[0194] 1,3-dimethyl-3,4,5,6-tetrahydro-2-1H-pyrimidinone
[0195] 5-(hydroxymethyl-2,4-(1H,3H)-pyrimidinedione
[0196] 2,4-dihydroxypyrimidine-5-carboxylic acid
[0197] 6-azathymine
[0198] 5-methyl-1,3,5-triazinan-2-one
[0199] N-carbamoylmaleamic acid
[0200] alloxan monohydrate
[0201] Among the compounds of formula (I) that may especially be
mentioned are the following particularly preferred compounds:
[0202] urea
[0203] methylurea
[0204] ethylurea
[0205] propylurea
[0206] 1-ethoxyurea
[0207] 2-hydroxyethylurea
[0208] N-(2-hydroxypropyl)urea
[0209] N-(3-hydroxypropyl)urea
[0210] N-(2-dimethylaminopropyl)urea
[0211] N-(3-dimethylaminopropyl)urea
[0212] 1-(3-hydroxyphenyl)urea
[0213] N-carbamoylmaleimide
[0214] N-carbamoylmaleamic acid
[0215] 1-piperidinecarboxamide
[0216] 1,2,4-triazol-4-ylurea
[0217] hydantoic acid
[0218] acetylurea
[0219] 2-hydroxyethyleneurea
[0220] 2-(hydroxyethyl)ethyleneurea
[0221] N-allyl-N'-ethylurea
[0222] diallylurea
[0223] 2-chloroethylurea
[0224] N,N-dimethylurea
[0225] 1,3-dimethylurea
[0226] 1,3-diethylurea
[0227] 1,3-bis(2-hydroxyethyl)urea
[0228] 1,3-dipropylurea
[0229] 1-ethyl-3-propylurea
[0230] N-acetyl-N'-methylurea
[0231] benzylurea
[0232] Among the compounds of formula (II) that may especially be
mentioned are the following particularly preferred compounds:
[0233] 1,2-dihydro-3H-1,2,4-triazol-2-one
[0234] uracil
[0235] 1-methyl-2-imidazolidinone
[0236] 1,3-dimethyl-2-imidazolidinone
[0237] 4,5-dihydroxyimidazolidin-2-one
[0238] 1-(2-hydroxyethyl)-2-imidazolidinone
[0239] 4,5-dihydroxy-1,3-dimethylimidazolidin-2-one
[0240] 1,3-bis(2-hydroxyethyl)-2-imidazolidinone
[0241] 2-imidazolidone-4-carboxylic acid
[0242] 1-(2-aminoethyl)-2-imidazole
[0243] hydantoin
[0244] 5-hydroxymethylhydantoin
[0245] hydantoin 5-acetic acid
[0246] urazole
[0247] orotic acid
[0248] dihydroxyorotic acid
[0249] 2,4,5-trihydroxypyrimidine
[0250] 4,5-diamino-2,6-dihydroxypyrimidine
[0251] 2,4-dihydroxypyrimidine-5-carboxylic acid
[0252] 5-methyl-1,3,5-triazinan-2-one
[0253] 1,3-dimethyl-3,4,5,6-tetrahydro-2-1H-pyrimidinone
[0254] N-carbamoylmaleamic acid
[0255] alloxan monohydrate
[0256] As "guanidine" that may be used as relaxing active agent,
this term means any derivative comprising in its chemical formula
at least one carbon atom doubly bonded to a nitrogen atom and
singly bonded to two other nitrogen atoms. These guanidines are
more particularly selected from the compounds of general formula
(III) below: ##STR5##
[0257] in which:
[0258] R1, R2, R3, R4 and R5 represent, independently:
[0259] (iii) a hydrogen atom, or
[0260] (iv) a linear or branched C1-C4 lower alkyl or alkenyl
radical, optionally substituted with one or two radicals chosen
from: hydroxyl, amino, dimethylamino, methoxy, ethoxy, carboxyl,
carboxamide, N-methylcarboxamide or SO.sub.3H
[0261] When R1, R2, R3 and R4 represent a hydrogen atom, R5 may
also denote a radical chosen from the following: acetyl;
chloroacetyl; carboxamide; methoxy; ethoxy; 1,2,4-triazolyl;
cyclopentyl; methoxycarbonyl; ethoxycarbonyl; CO--CH.dbd.CH--COOH;
phenyl optionally substituted with a chlorine atom or a hydroxyl
radical; benzyl; thiazolidone; benzimidazole; benzoxazole;
benzothiazole; or C(.dbd.NH)--NR6R7 in which R6 and R7 denote,
independently of each other, a hydrogen atom or a linear or
branched C1-C4 lower alkyl radical, optionally substituted with one
or two radicals chosen from: hydroxyl, amino, dimethylamino,
carboxyl and carboxamide; or N-methylcarboxamide; or alternatively
a phenyl radical.
[0262] When R1=R2=R3=H, R4 and R5 may also form, with the nitrogen
atom that bears them, a pyrrolidine, piperidine, pyrazole or
1,2,4-triazole ring, optionally substituted with one or two
radicals chosen from: hydroxyl, amino and carboxyl.
[0263] When R1=R2=H, and R4=H or methyl, R3 and R5 may also
together form a 5-membered ring optionally containing an oxo
group
[0264] and the organic or mineral salts thereof.
[0265] Among the compounds of formula (III) that may especially be
mentioned are the following preferred compounds:
[0266] guanidine hydrochloride guanidine acetate
[0267] guanidine sulfate
[0268] guanidine carbonate
[0269] guanidine bicarbonate
[0270] guanidine phosphate
[0271] guanidine sulfamate
[0272] aminoguanidine
[0273] aminoguanidine hydrochloride
[0274] aminoguanidine sulfate
[0275] aminoguanidine bicarbonate
[0276] 1,3-diaminoguanidine hydrochloride
[0277] 1-acetylguanidine
[0278] chloroacetylguanidine hydrochloride
[0279] guanylurea
[0280] guanylurea phosphate
[0281] phenylguanidine carbonate
[0282] phenylguanidine bicarbonate
[0283] 1-methylguanidine hydrochloride
[0284] 1,1-dimethylguanidine hydrochloride
[0285] 1-ethylguanidine hydrochloride
[0286] 1,1-diethylguanidine hydrochloride
[0287] creatine.
[0288] creatine monohydrate
[0289] creatinine hydrochloride
[0290] agmatine
[0291] agmatine sulfate
[0292] guanidinoacetic acid
[0293] guanidinosuccinic acid
[0294] 3-guanidinopropionic acid
[0295] 4-guanidinobutyric acid
[0296] 5-guanidinovaleric acid
[0297] beta-N-methylguanidinopropionic acid
[0298] N-methylguanidinopropionic acid
[0299] N-(2-hydroxyethyl)guanidine
[0300] N-(3-hydroxypropyl)guanidine
[0301] biguanide hydrochloride
[0302] N-methylbiguanide hydrochloride
[0303] N-ethylbiguanide hydrochloride
[0304] N-propylbiguanide hydrochloride
[0305] N-butylbiguanide hydrochloride
[0306] 1,1-dimethylbiguanide hydrochloride
[0307] 1-phenylbiguanide
[0308] 1,1,3,3-tetramethylguanidine hydrochloride
[0309] 2-tert-butyl-1,1,3,3-tetramethylguanidine hydrochloride
[0310] L-arginine
[0311] D-arginine
[0312] DL-arginine
[0313] arginic acid
[0314] N-amidino-N-(2,3-dihydroxypropyl)glycine
[0315] N-amidinotaurine
[0316] 2-imino-1-imidazolidineacetic acid
[0317] 1-(2,2-diethoxyethyl)guanidine
[0318] 1H-pyrazole-1-carboxamidine hydrochloride
[0319] 5-hydroxy-3-methyl-1H-pyrazole-1-carboximidamide
[0320] 3,5-diamino-1H-1,2,4-triazole-1-carboximidamide
hydrochloride
[0321] 2-guanidone-4-thiazolidone
[0322] 2-guanidinobenzimidazole
[0323] 2-guanidinobenzoxazole
[0324] 2-guanidinobenzothiazole
[0325] pyrrolidinoformamidine hydrochloride
[0326] Among the compounds of formula (III) that may especially be
mentioned are the following particularly preferred compounds:
[0327] guanidine hydrochloride
[0328] guanidine acetate
[0329] guanidine sulfate
[0330] guanidine carbonate
[0331] guanidine bicarbonate
[0332] guanidine phosphate
[0333] guanidine sulfamate
[0334] aminoguanidine hydrochloride
[0335] aminoguanidine sulfate
[0336] aminoguanidine bicarbonate
[0337] 1,3-diaminoguanidine hydrochloride
[0338] guanylurea phosphate
[0339] 1-methylguanidine hydrochloride
[0340] 1,1-dimethylguanidine hydrochloride
[0341] 1-ethylguanidine hydrochloride
[0342] creatine monohydrate
[0343] creatinine hydrochloride
[0344] agmatine
[0345] agmatine sulfate
[0346] guanidinoacetic acid
[0347] guanidinosuccinic acid
[0348] 3-guanidinopropionic acid
[0349] beta-N-methylguanidinopropionic acid
[0350] N-methylguanidinopropionic acid
[0351] N-(2-hydroxyethyl)guanidine
[0352] N-(3-hydroxypropyl)guanidine
[0353] biguanide hydrochloride
[0354] N-methylbiguanide hydrochloride
[0355] N-ethylbiguanide hydrochloride
[0356] 1,1-dimethylbiguanide hydrochloride
[0357] 1,1,3,3-tetramethylguanidine hydrochloride
[0358] 2-tert-butyl-1,1,3,3-tetramethylguanidine hydrochloride
[0359] L-arginine
[0360] DL-arginine
[0361] arginic acid
[0362] N-amidino-N-(2,3-dihydroxypropyl)glycine
[0363] N-amidinotaurine
[0364] 2-imino-1-imidazolidineacetic acid
[0365] 1H-pyrazole-1-carboxamidine hydrochloride
[0366] 3,5-diamino-1H-1,2,4-triazole-1-carboximidamide
hydrochloride
[0367] 2-guanidone-4-thiazolidone
[0368] In the compositions according to the invention, the urea of
formula (I) or (II) or the guanidine of formula (III) is
advantageously present in a molar concentration of between 1M and
8M and more advantageously at a concentration of between 2M and 8M.
Of course, any combination of two or more active agents can be used
in combination herein.
[0369] The pH of the compositions according to the invention is
preferably between 3 and 10 and more particularly between 5 and
9.
[0370] Advantageously, in the compositions of the invention, the
urea of formula (I) or (II) or the guanidine of formula (III) is
the sole relaxing active agent.
[0371] The compositions according to the invention are preferably
either in the form of an aqueous solution or in the form of a
thickened cream so as to keep the hair as straight as possible.
These creams are preferably made in the form of "heavy"
emulsions.
[0372] For the purpose of improving the cosmetic properties of
keratin fibres or alternatively of attenuating or avoiding their
degradation, the composition used according to the invention may
also comprise one or more additional cosmetic active agents.
[0373] Generally, the additional cosmetic active agent(s)
represent(s) from 0.01% to 30% and preferably from 0.1% to 10% by
weight relative to the total weight of the cosmetic
composition.
[0374] Generally, the composition applied to the keratin fibres is
applied at a rate of from 0.05 to 20 g and preferably from 0.1 to
10 g of composition per gram of dry keratin fibre.
[0375] In a preferred embodiment, after applying the composition,
and before raising the temperature of the keratin fibres using a
heater or heating means, the composition may be left to stand on
the fibres, generally for between 30 seconds and 60 minutes and
preferably 5 to 45 minutes.
[0376] The process according to the invention comprises, preferably
after applying the composition, raising the temperature of the
keratin fibres to a temperature of between 110.degree. C. and
250.degree. C.
[0377] Advantageously, an iron is used as a heater or heating
means.
[0378] For the purposes of the present invention, the term "iron"
means a device for heating keratin fibres by placing the fibres and
the heating device in contact.
[0379] The end of the iron that comes into contact with the hair
generally has two flat surfaces. These two flat surfaces may be
metallic. They may be smooth or notched.
[0380] As examples of irons that may be used in the process
according to the invention, mention may preferably be made of any
type of flat iron and in particular, in a non-limiting manner,
those described in U.S. Pat. No. 5,957,140 and U.S. Pat. No.
5,046,516.
[0381] The application of the iron may be performed by successive
touches separated by a few seconds, or by gradual moving or sliding
along locks, etc.
[0382] Preferably, the application of the iron in the process
according to the invention is performed by continuous movement from
the root to the end, in one or more passes.
[0383] The process according to the invention may also comprise
partial predrying of the keratin fibres before raising the
temperature, so as to avoid substantial release of steam that might
burn the hands of the hairstylist and the individual's scalp. This
predrying step may be performed, for example, using a hairdryer, a
drying hood or by free drying.
EXAMPLES
[0384] The invention will be understood more clearly with the aid
of the non-limiting examples that follow, which constitute
preferred embodiments of the invention.
Example 1
[0385] A simplified relaxing composition containing urea, at a
concentration of 8M in water, as relaxing active agent is prepared.
The pH of the composition is 8.06. This composition is applied to
naturally frizzy African hair for 15 minutes at a temperature of
40.degree. C. and the hair is then rapidly wiped with a towel.
[0386] The hair is then straightened lock by lock using a flat iron
heated to 180.degree. C. for 5 to 10 seconds. The hair is
efficiently relaxed and feels soft.
Example 2
[0387] A simplified relaxing composition containing urea, at a
concentration of 4M in water, as relaxing active agent is prepared.
The pH of the composition is 7.7. This composition is applied to
naturally frizzy African hair for 25 minutes at a temperature of
40.degree. C. and the hair is then rapidly wiped with a towel.
[0388] The hair is then straightened lock by lock using a flat iron
heated to 180.degree. C., for 5 to 10 seconds. The hair is
efficiently relaxed and feels soft.
Example 3
[0389] A simplified relaxing composition containing guanidine
hydrochloride, at a concentration of 8M in water, as relaxing
active agent is prepared. The pH of the composition is 5.46. This
composition is applied to naturally frizzy African hair for 15
minutes, at a temperature of 40.degree. C. and the hair is then
rapidly wiped with a towel.
[0390] The hair is then straightened lock by lock using a flat iron
heated to 180.degree. C., for 5 to 10 seconds. The hair is
efficiently relaxed and feels soft.
[0391] The invention process for relaxing keratin fibres includes
hair relaxing, uncurling and straightening, etc. While the
invention can be thought of as involving distinct acts, such as
[0392] (i) applying to the keratin fibres a relaxing composition
containing at least one denaturing agent with a molecular mass of
greater than 18.1 g/mol, present in a molar concentration of
between 1M and 8M, and
[0393] (ii) raising the temperature of the keratin fibres, using a
heater or heating means, to a temperature of between 110 and
250.degree. C.,
[0394] it can also be thought of as a method comprising raising the
temperature of keratin fibres, using a heater or heating means, to
a temperature of between 110 and 250.degree. C. wherein said
keratin fibres comprise on at least a part of a surface thereof at
least one denaturing agent with a molecular mass of greater than
18.1 g/mol.
[0395] The above written description of the invention provides a
manner and process of making and using it such that any person
skilled in this art is enabled to make and use the same, this
enablement being provided in particular for the subject matter of
the appended claims, which make up a part of the original
description and including a process for relaxing keratin fibres
comprising:
[0396] (i) applying to the keratin fibres a relaxing composition
comprising, consisting essentially of, or consisting of, at least
one denaturing agent with a molecular mass of greater than 18.1
g/mol, present in a molar concentration of between 1M and 8M,
and
[0397] (ii) raising the temperature of the keratin fibres to a
temperature of between 110 and 250.degree. C., as well as a method
comprising raising the temperature of keratin fibres to a
temperature of between 110 and 250.degree. C. wherein said keratin
fibres comprise on at least a part of a surface thereof at least
one denaturing agent with a molecular mass of greater than 18.1
g/mol.
[0398] As used above, the phrases "selected from the group
consisting of," "chosen from," and the like include mixtures of the
specified materials.
[0399] All references, patents, applications, tests, standards,
documents, publications, brochures, texts, articles, etc. mentioned
herein are incorporated herein by reference. Where a numerical
limit or range is stated, the endpoints are included. Also, all
values and subranges within a numerical limit or range are
specifically included as if explicitly written out. Terms such as
"contain(s)" and the like as used herein are open terms meaning
`including at least` unless otherwise specifically noted.
[0400] The above description is presented to enable a person
skilled in the art to make and use the invention, and is provided
in the context of a particular application and its requirements.
Various modifications to the preferred embodiments will be readily
apparent to those skilled in the art, and the generic principles
defined herein may be applied to other embodiments and applications
without departing from the spirit and scope of the invention. Thus,
this invention is not intended to be limited to the embodiments
shown, but is to be accorded the widest scope consistent with the
principles and features disclosed herein.
* * * * *