Hair straightening method and texturing strengthener compositions therefor

This invention relates to a method of straightening, texturing and strengthening hair undergoing an alkaline straightening procedure and to nonacidic aqueous hair texturing and strengthening compositions for use in conjunction therewith. The texturing and strengthening compositions have a pH value from at least 8 to about 11 containing at least one water-dispersible hair texturing and strengthening agent including a quaternary nitrogen atom with at least one aliphatic alkyl group directly or indirectly bonded to the quaternary nitrogen atom, the aliphatic alkyl group having from about 3 to about 22 carbon atoms. Methods for applying the compositions in post-straightening and pre-straightening procedures are disclosed.

TECHNICAL FIELD 
This invention relates to the art of chemically straightening human hair 
and to texturing strengthener compositions for use in conjunction with 
alkaline hair straighteners. More particularly, non-acidic compositions 
are provided which contain a cationic texturing strengthening agent to 
simultaneously texturize and strengthen hair undergoing a highly alkaline 
straightening procedure. 
BACKGROUND OF THE INVENTION 
Until now, practitioners of chemical hair straightening arts have been 
unable to successfully increase and maintain negatively-charged cation 
receptive sites in alkali-straightened (relaxed) hair to simultaneously 
strengthen and restore its textural quality to that substantially 
resembling hair in relatively good condition. 
Most commonly used relaxers are based on hydroxide-containing alkalis, 
sulfites or thioglycolates. Of these, the most effective and popular are 
alkaline straightener compositions that produce stable lanthionine 
linkages in the hair. These chemical hair straighteners usually contain 
relatively strong alkalis, such as sodium hydroxide, potassium hydroxide, 
calcium hydroxide, lithium hydroxide and guanidine hydroxide. The highly 
alkaline conditions (pH 12 to 14) of these products, however, causes a 
substantial amount of swelling in human hair. Consequently, some 
hydrolysis of the polypeptide chains in the hair protein at about pH 12.5 
is inevitable. 
Prolonged or unnecessary exposure of hair to a strong alkali weakens, 
breaks and even dissolves the hair. Thus, it is an accepted practice to 
minimize the time that the hair is exposed to highly alkaline hair 
straighteners. Towards this end, substantially all the straightener is 
immediately rinsed from the hair as soon as the desired partial or 
complete straightening effect is achieved. Further, to remove any residual 
hair straightener remaining in the rinsed hair, and to deswell the hair, 
an acidic neutralizer is applied immediately thereafter to the rinsed 
alkali-treated hair. Generally this acidic neutralizer is a nonalkaline 
shampoo or an acid rinse having a pH below 7, usually in a pH range 
between about 1 to about 6 and preferably close to the isoelectric region 
of human hair, approximately pH 4. 
Some success in preventing further alkali attack on the hair is achieved by 
deswelling the hair in the foregoing manner. However, the textural quality 
of acid-treated hair is harsh and strawlike, unless known conditioners are 
included in the shampoo or rinse. The term "conditioners" refers to 
cosmetically useful emollients, such as oils, quaternary ammonium salts, 
cationic polymers and the like, known to those skilled in hair 
conditioning art. 
It is known that human hair is negatively charged, i.e., more anionic, 
above its isoelectric region, and hence, more receptive to adsorbing 
cationic materials. There is also some indication that the cationic 
qualities of certain quaternary ammonium salts are enhanced under alkaline 
conditions. Finkelstein, et al., "The Mechanism of Conditioning of Hair 
with Alkyl Quaternary Ammonium Compounds," App. Polym. Symp., 18, 673 
(1971), for example, report that the cationic properties of 
stearyltrimethyl ammonium chloride are greater at pH 7.5 than at pH 4.5. 
However, any attempt to enhance or sustain the cation-receptivity of 
alkali-straightened hair by further exposing it immediately to a 
non-acidic composition having a pH greater than 7 is generally avoided. 
Thus, the non-polymeric quaternary ammonium salts often used for hair 
conditioning are employed at relatively low pH values rather than at 
higher pH values. Under alkaline conditions, such compounds tend to 
deposit an unacceptable delustering coating on the hair. Also, because of 
their relatively small molecular size, they are easily removed from the 
hair so conditioning benefits obtained are temporary. 
As a result, cationic polymers, especially those containing quaternary 
nitrogen atoms, are more often used in hair conditioning compositions, 
because these polymers are usually substantive to hair at acidic pH 
values. The term "substantive" cannot be defined by distinctive 
physicochemical properties, but involves mechanisms such as adsorption, 
ion exchange and chemical interaction. As used herein, the term 
"substantive" or its grammatical variant "substantivity" refers to the 
retention of a cationic material deposited or absorbed on the hair through 
several shampoo applications. 
Not all cationic polymers, however, are alkali-compatible or stable under 
alkaline conditions. Some cationic polymers must first be complexed with 
some anionically active component already present on the hair or in the 
neutralizing shampoo to form a conditioning reaction product. 
Proteinaceous materials that are water-soluble and substantive to hair are 
also known desirable compounds. A number of water-soluble hydrolyzed 
protein compounds are commercially available, some of which display 
cationic qualities under acidic conditions. However, their utility under 
alkaline conditions is limited, because they become neutral or anionic in 
character and some degradation of the amide groups in the protein portion 
takes place. Consequently, their use in non-acidic compositions is 
generally avoided. 
Prior attempts have been limited, therefore, to applying conditioners under 
acidic or neutral conditions to at least improve the tactile feel, if not 
the strength of the alkali-straightened hair. 
In one approach, a non-alkaline composition containing one or more of the 
foregoing conditioners is applied to the hair before the hair 
straightener. However, one drawback of this approach is that any 
conditioning benefit achieved generally does not survive the subsequent 
highly alkaline chemical straightening procedure. In addition, these 
conditioners may weaken the strength of the hair straightener product or 
interfere with its effectiveness. 
This drawback was partially overcome by including a quaternary 
nitrogen-containing cationic polymer in the alkaline hair straightener 
product as described in U.S. Pat. No. 4,175,572. Such a product is 
presently marketed. However, the residual alkalinity in the hair follwing 
use of this product is substantially immediately neutralized by 
application of a non-alkaline neutralizing shampoo. 
In another approach, a conditioning nonalkaline shampoo neutralizer is 
employed immediately after rinsing the straightener from the hair with 
water. However, a shampoo, by the manner in which it must be used, 
contacts the hair too briefly to maximize adsorption of cationic 
materials. Further, alkali-weakened hair may not withstand the 
manipulative actions inherently required for the shampooing process so 
some hair loss or breakage can occur. 
U.S. Pat. No. 4,602,648 (hereafter the '648 patent) discloses the use of 
hydrolyzed proteins and/or cationic polymers in a "pre-shampoo normalizer" 
so-called because it is applied between the straightening step and the 
shampooing step. Several products following such a procedure are presently 
being marketed. However, the effectiveness of such normalizer compositions 
suffers the same drawbacks of prior acidic compositions. 
The pre-shampoo normalizers of the '648 patent are acidic or nonalkaline 
compositions that are adjusted by the addition of acid to a pH of between 
2.5 and 7. Thus, these compositions decrease, rather than increase, 
cation-receptive negatively-charged sites in the hair as the acidity of 
the composition neutralizes the alkaline residue in the hair. Thus, this 
approach constitutes, in effect, an acidic neutralization procedure, 
because the '648 patent normalizer step is followed by a shampooing step 
to remove both residual straightener and residual normalizer composition 
from the hair. 
The '648 patent purports to take advantage of the sensitive state of the 
hair at a relatively high alkaline pH of between about 9 and 11 after the 
straightener treatment to mediate damage and improve the aesthetic 
qualities of the straightened hair. However, we have found from experience 
that when the method of this patent is followed, substantive conditioning 
and strengthening are not simultaneously achieved. This was determined by 
measuring the strength and subjective textural qualities of the 
straightened hair. 
There is a need for a relatively simple method and a product that 
simultaneously strengthen and enhance the cation-receptivity of hair 
undergoing or about to undergo a highly alkaline hair straightening 
procedure. We have now surprisingly found that the cation-receptivity of 
alkalistraightened hair can be enhanced and sustained, while the hair is 
simultaneously strengthened, by applying the non-acidic compositions of 
this invention to hair in a post-straightening and pre-straightening step. 
The hair straightening method and texturing strengthener compositions of 
this invention satisfy that need. 
SUMMARY OF THE INVENTION 
This invention relates to a method of simultaneously straightening, 
texturing and strengthening hair undergoing an alkaline straightening 
procedure, and particularly to non-acidic aqueous texturing and 
strengthening compositions for use in conjunction with such highly 
alkaline hair straighteners. 
The term "highly alkaline" used in connection with hair straighteners 
refers to products that contain alkaline straightening agents that provide 
a pH value of about 12 to about 14. These are generally known to those 
skilled in the hair straightening art as "lye" and "no-lye" relaxers. The 
term "non-acidic", as applied to compositions of this invention, relates 
to vehicles containing no ionizable hydrogen-containing substances capable 
of neutralizing residual alkali on the hair from the hair straightener 
product. 
In one embodiment of the method of this invention, a texturing and 
strengthening agent contained in an aqueous composition having a pH of 
from between at least 8 to about 11 is applied in a post-straightening 
step, as disclosed herein, to enhance and sustain cation receptive 
negatively-charged sites in hair which has just undergone an alkali 
straightening procedure. The post-straightening step follows substantially 
immediately after the hair straightener is rinsed from the hair. 
In another embodiment, the above method includes applying an auxiliary 
amount of the texturing and strengthening agent contained in an aqueous 
texturing and strengthening composition in a pre-straightening step to 
hair about to undergo the straightening procedure. An auxiliary amount 
refers to an amount of hair texturing and strengthening agent applied to 
either the virgin outgrowth portion or previously treated outgrowth 
portion of the hair in addition to the amount of hair texturing and 
strengthening agent applied in the post-straightening step. The 
pre-straightening step is substantially immediately before the hair 
straightener is applied to the hair. The auxiliary amount of hair 
texturing and strengthening agent applied to the hair in the 
pre-straightening step can be provided in a non-acidic aqueous composition 
that is the same or different from that applied in the post-straightening 
step. 
Texturing and strengthening is substantially achieved within about 5 
minutes of the post-straightening step. However, the method includes a 
shampooing step to cleanse the hair and scalp of residual hair 
straightener, if any, and excess texturing and straightening composition. 
The term "texturing" or its grammatical variant "texturize" refers to those 
physical, chemical and mechanical characteristics of hair associated with 
subjectively discernible changes in the textural qualities of the hair and 
its tensile strength. 
The terms "strength" and "strengthening" as used in connection with 
alkali-straightened hair refer to changes in mechanical properties of hair 
fibers related to the overall dynamic and static moduli of a hair fiber, 
as measured by stress-strain and breaking force techniques. Loss of 
strength and swelling are generally associated in straightened hair with 
weakened fiber integrity, such that the alkali-straightened hair can break 
during shampooing or combing. Weakened hair is also associated with poor 
textural qualities (spongy, rubbery) that negatively affect its hand. 
The term "hand", as used herein, refers to the subjective feel of the hair 
or tactile reaction to such textural qualities as smoothness, softness and 
flexibility when the hair is combed or manipulated during styling. The 
term "fiber integrity" as used herein includes those physical and chemical 
characteristics of intact hair subjectively associated with the mechanical 
properties of hair condition, i.e., easy combability, manageability and 
hand. 
We have surprisingly found that hair undergoing a highly alkaline 
straightening procedure can be simultaneously textured and strengthened by 
aqueous texturing and strengthening compositions of this invention which 
have a pH of at least 8 or greater and contain certain cationic hair 
texturing and strengthening agents. 
In one embodiment, an aqueous hair texturing and strengthening composition 
of this invention has a pH value from at least 8 to about 11, preferably 
from at least 8 to about 9. The composition includes at least one 
water-dispersible hair texturing and strengthening agent including a 
quaternary nitrogen atom with at least one aliphatic alkyl group directly 
or indirectly bonded to the quaternary nitrogen atom. The aliphatic alkyl 
group has from about 3 to about 22 carbon atoms. For achieving the desired 
pH, the compositions can include a base. 
Suitable water-dispersible texturing and strengthening agents include 
quaternary ammonium derivatives of a hydrolyzed animal protein and 
quaternary nitrogen-containing compounds including at least one aliphatic 
alkyl group bonded directly or indirectly to the quaternary nitrogen atom. 
Each alkyl group preferably contains from about 8 to about 18 carbon atoms 
and the remainder of the groups bonded to the quaternary nitrogen atom 
include alkyl groups having from 1 to about 4 carbon atoms, a benzyl 
radical and combinations thereof. The term "waterdispersible", as used 
herein in connection with cationic materials, includes water-soluble 
compounds that form substantially clear solutions when dispersed or 
dissolved in water. 
In a preferred embodiment of the composition, the hair texturing and 
strengthening agent is a quaternary ammonium derivative of a hydrolyzed 
collagen protein in which over about 70 percent of the available amino 
groups have been quaternized to incorporate at least one aliphatic alkyl 
group having from about 3 to about 18 carbon atoms in the aliphatic alkyl 
group. A particularly preferred quaternary ammonium derivative of 
hydrolyzed collagen protein incorporates from about 12 to about 18 carbon 
atoms in at least one aliphatic alkyl group, has a weight average 
molecular weight from about 2500 to about 12,000, and has an isoionic 
point from about 9.5 to about 11.5. 
For augmenting the texturing effect on alkali-straightened hair, a hair 
texturing and strengthening composition of this invention includes a 
water-dispersible cationic polymer. The term "cationic polymer" as used 
herein includes quaternized polymers containing at least one positively 
charged nitrogen atom in each repeating unit of the polymer chain, 
unquaternized polymers having tertiary amino nitrogen groups that become 
quaternized when protonated and corresponding copolymers thereof. A 
particularly preferred polymer is a polydiallyldialkyl ammonium chloride 
homopolymer in which the alkyl group contains from 2 to 3 carbon atoms, 
and the polymer has a weight average molecular weight of about 100,000. 
The methods and compositions of this invention have many advantages and 
benefits. One advantage is that the cation receptivity of alkali-treated 
hair is enhanced and sustained to strengthen the hair while shampoo 
resistant texturing benefits are provided. Another benefit is that 
compositions can be applied to previously untreated virgin growth portions 
of the hair to make the hair more cation-receptive prior to undergoing the 
alkaline straightening procedure. Yet another benefit is that previously 
straightened outgrowth portions of the hair can also be textured with 
non-acidic compositions without interfering with the subsequent alkaline 
straightening procedure. 
Still further benefits and advantages of the present invention will become 
apparent to those skilled in the art from the detailed description of the 
invention, the examples and the claims that follow.

DETAILED DESCRIPTION OF THE INVENTION 
The method of this invention provides for texturing and strengthening hair 
about to undergo or having just undergone an alkaline hair straightening 
(relaxing) procedure. Such compositions typically contain as the active 
hair straightening agent relatively strong alkalis such as sodium 
hydroxide, potassium hydroxide, calcium hydroxide, lithium hydroxide, 
guanidine hydroxide and quaternary ammonium hydroxide. For convenience, 
hair that has undergone a highly alkaline hair straightening procedure at 
a pH of about 12 to about 14 is referred to herein simply as 
alkali-straightened hair or relaxed hair. 
The mechanism of simultaneously texturing and strengthening 
alkali-straightened hair by compositions of this invention is not fully 
understood. We believe that negatively charged sites in 
alkali-straightened hair are sustained by compositions of this invention 
having a pH of at least 8 resulting in enhanced cation substantivity on 
the hair without impairing fiber integrity. The available positively 
charged sites in the texturing and strengthening agent may bind to the 
negatively charged sites in the hair to provide a discernible improvement 
in the textural qualities of the alkali-straightened hair that lasts 
through subsequent shampoo procedures. Further, the strength of the 
alkali-treated hair simultaneously improves as measured by break force and 
intermittent stress strain modulus techniques described below. However, 
the effectiveness of the present methods and compositions does not depend 
upon and is not limited by the foregoing description of a proposed 
mechanism. 
The texturing and strengthening agent of this invention is a 
water-dispersible quaternary nitrogen-containing compound having at least 
one aliphatic alkyl group directly or indirectly bonded to a quaternary 
nitrogen atom. The aliphatic alkyl group preferably includes from about 3 
to about 22 carbon atoms. Particularly preferred aliphatic alkyl groups 
are lipophilic fatty acid derivatives of a natural or synthetic fatty acid 
or a source of fatty acids, either linear or branched, containing from 
about 12 to about 18 carbon atoms. 
Suitable texturing and strengthening agents are proteinaceous and 
nonproteinaceous quaternary ammonium compounds. These compounds include 
quaternary ammonium derivatives of a hydrolyzed animal protein and 
quaternary nitrogen-containing compounds including at least one aliphatic 
alkyl groups bonded directly or indirectly to the quaternary nitrogen 
atom. Each alkyl group preferably contains from about 8 to about 18 carbon 
atoms and the remainder of the quaternary nitrogen bonds include alkyl 
groups having from 1 to about 4 carbon atoms, a benzyl radical and 
combinations thereof. 
Preferably, the quaternary nitrogen of the quaternary ammonium compound 
retains its positive charge and is stable at an alkaline pH in the range 
of at least pH 8 to about 11. Especially preferred are quaternary ammonium 
compounds that are substantive to hair and which disperse in water to 
provide solutions that are substantially clear at a pH above 8. 
Examples of water-dispersible proteinaceous quaternary ammonium compounds 
include derivatives of chemically-modified hydrolyzed animal protein, such 
as quaternary ammonium derivatives of hydrolyzed collagen protein 
including at least one aliphatic alkyl group having from about 12 to about 
18 carbon atoms in the aliphatic alkyl group. Compounds of this type that 
are commercially available include the following compositions aid by 
Croda, Inc., New York, NY: lauryldimethylammonium hydrolyzed animal 
protein (trade name CROQUAT L); coconutdimethylammonium hydrolyzed animal 
protein (trade name CROQUAT M); stearyldimethylammonium hydrolyzed animal 
protein (trade name CROQUAT S); stearyltrimethylammonium animal protein 
(trade name CROTEIN Q); and the following compositions sold by Inolex 
Chemical Company, Philadelphia, PA: cocoamidodimethylhydroxypropylamino 
hydrolyzed animal protein (trade name LEXEIN QX3000) and 
oleamidopropyldimethylamine hydrolyzed animal protein (trade name LEXEIN 
CP125). Another illustrative quaternary ammonium derivative of collagen 
protein that includes an aliphatic alkyl group containing 3 carbon atoms 
is commercially available from Hormel, Oak Brook, IL, under the name 
PROLAGEN MP-1. The foregoing list is intended to be illustrative and not 
limiting. 
Particularly preferred is the quaternary ammonium derivative of hydrolyzed 
collagen protein sold under the trade name CROQUAT M by Croda, Inc. This 
compound, and the structurally related CROQUAT L and CROQUAT S 
derivatives, are reported to have at least 70 percent of the available 
amino acid groups in the collagen quaternized. Thus, these compounds are 
alkyl dimethyl ammonium chloride derivatives having a plurality of 
quaternary nitrogen-containing alkyl dimethyl moieties covalently bonded 
directly to the peptide chain and are reported to have a hydroxyproline 
content of about 4.5 percent to about 6 percent. The Croquat materials 
reportedly have an isoionic point in the range of about 10 to about 11.5 
and retain their net positive charge at a pH value of about 9.5. 
Likewise, another preferred quaternary ammonium derivative of hydrolyzed 
collagen protein is sold under the trade name CROTEIN Q by Croda, Inc. 
This material is reported to have over 90 percent of its available amino 
acid groups quaternized and the amino acid residues are indirectly bonded 
to a quaternary nitrogen atom by an 18 carbon aliphatic alkyl chain. The 
aliphatic alkyl chain including the hydrolyzed protein is directly bonded 
to a quaternary nitrogen atom with the remaining quaternary nitrogen bonds 
taken up with methyl groups. CROTEIN Q is reported to have a isoionic 
point in the range of about 9.5 to about 10.5 and is positively charged at 
all pH values up to an isoelectric point of about 10. 
The term "isoionic point" refers to the pH range in which the proteinaceous 
quaternary ammonium compound is ionically charged. The term "isoelectric 
point" refers to the pH at which the proteinaceous quaternary ammonium 
compound has no net charge. 
Non-proteinaceous water-dispersible quaternary nitrogen-containing 
compounds containing at least one aliphatic alkyl group bonded directly or 
indirectly to the quaternary nitrogen atom include quaternary ammonium 
compounds in the form of a salt having a substantially innocuous inorganic 
or organic anion such as a halide, preferably chloride or bromide, 
sulfate, sulfite, phosphate, nitrate, nitrite, acetate, methylsulfate, 
ethosulfate and toluenesulfonate. 
Illustrative examples of non-proteinaceous water-dispersible quaternary 
nitrogen-containing compounds include octyltrimethyl ammonium chloride; 
decyltrimethyl ammonium chloride; lauryldimethylethyl ammonium chloride; 
lauryltrimethyl ammonium chloride; cetyldimethylethyl ammonium chloride; 
cetyltrimethyl ammonium chloride; tetradecyltrimethyl ammonium chloride; 
stearyltrimethyl ammonium chloride; 3-behenoyloxy-2-hydroxypropyltrimethyl 
ammonium chloride; behenyltrimethyl ammonium chloride; behenyltrimethyl 
ammonium methosulfate. Also suitable are dialkyldimethyl ammonium 
chlorides wherein each of the alkyl groups is a saturated group having 
from about 8 to about 18 carbon atoms, such as distearyldimethyl ammonium 
chloride; dilauryldimethyl ammonium chloride, didecyldimethyl ammonium 
chloride; di-hydrogenated tallow)-dimethyl ammonium chloride. Mixed higher 
alkyl trimethyl ammonium chlorides containing mixtures of predominantly 
long-chain aliphatic alkyl radicals having from about 8 to about 18 carbon 
chains in the alkyl group may also be used such as derivatives of coconut 
oil, tallow, soya bean oil, cottonseed oil, babassu oil, palm oil, etc. 
Compounds that correspond to the foregoing may also be employed where the 
anion is other than a halide, as noted above. 
A particularly preferred non-proteinacious water-dispersible quaternary 
nitrogen-containing compound has the CTFA adopted name of dicetyldimonium 
chloride and is an N-hexadecyl-N,N-dimethyl-1-hexadecaminium chloride 
corresponding to the commercial material sold under the trade name ADOGEN 
432CG by Sherex Chemical Company, Inc., Dublin, OH. 
Additional illustrative quaternary ammonium compounds include "benzyl 
quats" such as aliphatic alkyldimethylbenzyl ammonium chlorides having 
from about 8 to about 18 carbon atoms in the aliphatic alkyl group. These 
compounds include cetyldimethylbenzyl ammonium chloride; 
stearyldimethylbenzyl ammonium chloride; tetradecyldimethylbenzyl ammonium 
chloride; cetyldimethylbenzyl ammonium chloride; 
n-dodecyldimethyl-p-chlorobenzyl ammonium chloride; laurylpyridinium 
chloride; cetylpyridinium chloride; alkyl isoquinolinium chlorides or 
bromides having about 8 to about 18 carbon atoms in the alkyl chain, such 
as laurylisoquinolinium chloride; N-(acylcolaminoformylmethyl)-pyridinium 
chlorides and bromides wherein the acyl radical contains from 8 to 18 
carbon atoms, such as octoyl, lauroyl, palmitoyl and stearoyl, and the 
like. Another exemplary material is N-soya-N-ethyl morpholinium 
ethosulfate, such as the material sold under the trade name ATLAS G271 by 
ICI Americas, Inc., Wilmington, DE. This listing is by way of illustration 
and is not intended to be limiting. 
For practicing the method of this invention, the compositions contain at 
least one or more texturing and strengthening agents. Preferred 
compositions contain at least one quaternary ammonium derivative of a 
hydrolyzed protein as the texturing and strengthening agent. 
For practicing the principles of this invention, an effective amount of a 
texturing and strengthening agent is dispersed in water with sufficient 
base, if needed, to adjust the pH of the composition to between at least 
pH 8 to about pH 11, preferably from at least pH 8 to about pH 9, more 
preferably from about pH 8.1 to about pH 8.5. 
An effective amount of total texturing and strengthening agents present is 
from about 0.1 percent to about 8 percent by weight, preferably from about 
0.2 percent to about 6.0 percent by weight, and more preferably from about 
0.5 percent to about 5.0 percent by weight. Percent by weight as used 
herein refers to the weight of active dry solids based on the total weight 
of the composition. It is recognized that actual suitable amounts are 
limited only by the solubility or dispersibility of a selected compound in 
water and by economic considerations. It is also recognized that amounts 
greater than 8 percent can be used, but such amounts are believed 
unnecessary and wasteful. 
Bases suitable for adjusting the pH of the compositions include alkali 
metal hydroxides, and lower alkyl organic bases in which the alkyl group 
contains from 1 to about 6 carbon atoms commonly employed in the cosmetic 
arts. While it is recognized that a volatile base, such as ammonia, as 
well as the foregoing nonvolatile bases, can be used for purposes of 
achieving the desired pH, ammonia is not preferred to avoid swelling the 
alkali-treated hair or irritating the skin. 
Exemplary alkali metal hydroxides include sodium hydroxide and potassium 
hydroxide. The amount of sodium hydroxide employed is relatively small for 
adjusting the pH and, thus, is well below the amounts normally used in 
hair straighteners. 
Exemplary lower alkyl organic bases include primary alkylamines such as 
ethylamine or propylamine; secondary alkylamines such as diethylamine, 
morpholine or ethylpropylamine; tertiary amines such as triethylamine or 
quinuclidine; and preferably a hydroxyalkylamine containing 2 to 6 carbons 
per alkyl group bonded to the amine nitrogen atom such as 
monoethanolamine, diethanolamine, triethanolamine, monoisopropanolamine, 
diisopropanolamine, triisopropanolamine, 2-amino-1-butanol, 
1-amino-2-methyl-2-propanol and 2-amino-2-methyl-1-propanol. A 
particularly preferred base is triethanolamine. 
For purposes of augmenting the texturing effect on alkali-straightened 
hair, a water-dispersible cationic polymer can be included in compositions 
of this invention. Suitable cationic polymers preferably include 
quaternized polymers containing at least one positively charged nitrogen 
atom in each repeating unit of the polymer chain, but can include 
unquaternized polymers that behave like cationic polymers when protonated 
and corresponding copolymers of the foregoing. Preferably, cationic 
polymers useful in compositions of this invention retain their cationic 
positive charge at a pH above at least 8, provide substantially clear 
solutions when dispersed in water and are substantive to hair. 
Broadly, cationic polymers are useful in concentrations of about 0.01 
percent to about 5 percent by weight, preferably in amounts of about 0.1 
percent to about 3.5 percent by weight, and more preferably in amounts of 
about 0.2 to about 2.5 percent by weight. The percentage is expressed as 
the weight of dry solids based on the total weight of the composition. The 
weight average molecular weights of the polymers useful herein are broadly 
between about 3000 and about 10,000,000, with various useful polymers 
having a generally more narrow average molecular weight range. 
A number of cationic polymers, their manufacturers and general description 
of their composition can be found in the CTFA Cosmetic Ingredient 
Dictionary, 3rd ed., 1982 and in the CTFA Cosmetic Ingredient Dictionary, 
3rd ed., Supplement, 1985, both published by the Cosmetic Toiletry and 
Fragrance Association, Inc. (CTFA) and incorporated herein by reference. 
The official CTFA name assigned to ingredients appearing therein or as 
assigned by the manufacturer, when known, will be employed for 
convenience. 
Preferred cationic polymers include those prepared from 
polydiallyldialkylammonium salts containing from 2 to 3 carbon atoms in 
the alkyl group. The preparation of these polymers is described in U.S. 
Pat. Nos. 3,288,770 and 3,412,019. These polymers are sold commercially 
under the trade name MERQUAT by Merck & Company, Inc., Rahway, NJ. 
Particularly preferred is a polydiallyldimethylammonium chloride 
homopolymer designated polyquaternium-6 by the CTFA and sold under the 
trade name MERQUAT-100. This polymer is described as having a weight 
average molecular weight of approximately 100,000 and is supplied as a 40 
percent aqueous solution. Also preferred is a copolymer of 
diallyldimethylammonium chloride with acrylamide designated 
polyquaternium-7 by the CTFA and sold under the trade name MERQUAT-550. 
This material is described as having a weight average molecular weight of 
approximately 500,000 and is supplied as an 8 percent aqueous solution. A 
discussion of these materials and their properties is found in Sykes et 
al., "The Use of Merquat Polymers," Drug cosm. Ind., 126, 62 (1980) which 
is incorporated herein by reference. 
Other useful cationic polymers are quaternary ammonium derivatives of 
natural guar gum assigned CTFA names of guar hydroxypropyltrimonium 
chloride. Natural water-soluble polymers of cationic guar that are 
compatible over a wide pH range of from about 3 to about 11 are 
commercially available, sold under the trade names JAGUAR C-13, C-14-8, 
C-15 and C-17 by Celanese Corporation, Louisville, KY. Guar is a 
galactomannan with a structure composed of a straight backbone chain of 
D-mannopyranose units with a side branching unit of D-galactopyranose on 
every other unit and having an average molecular weight in the range of 
about 200,000 to about 300,000. A description of these cationic gums is 
found in Freeland et al., "Cationic Guar Gum," Cosmet. Toilet., 99, 83 
(1984) which is incorporated herein by reference. 
A listing of useful cationic polymers which is not intended to be 
exhaustive or limiting follows: 
adipic acid/epoxypropyl diethylenetriamine copolymer (sold by Hercules 
Inc., Wilmington, DE., under the name DELSETTE 101); 
adipic acid/dimethylaminohydroxypropyldiethylenetriamine copolymers (sold 
by Sandoz Chemicals Corporation, Charlotte NC, under the name CARTARETIN); 
polyquaternium-2, a poly[N-(3-dimethylamino) 
propyl]-N'-[3-(ethyleneoxyethylene dimethylamino)propyl]urea dichloride 
(sold by Miranol Chemical Company, Inc., Dayton, NJ under the name Mirapol 
A 15); 
quaternary ammonium polymers formed by the reaction of dimethyl sulfate and 
a copolymer of vinyl pyrrolidone and N,N-dimethylaminoethylmethacrylate 
(sold by GAF Corporation, Wayne, NJ under the names GAFQUAT-734 and 
GAFQUAT-755); polymers of hydroxyethyl cellulose reacted with 
epichlorohydrin and quaternized with trimethylamine (sold by Union Carbide 
Corporation, Danbury, CT under the trademark POLYMER JR and available in a 
range of various molecular weight sizes); 
copolymers prepared from acrylamide and N,N-dimethylaminoethyl methacrylate 
and quaternized with dimethyl sulfate (sold by Hercules, Inc. under the 
name RETEN); 
aminoethylacrylate phosphate/acrylate copolymer (sold by National Starch & 
Chemical Corporation, Bridgewater, NJ, under the name CATREX); 
polyquaternium-1 a polymeric quaternized dimethylbutenyl ammonium chloride 
terminated with quaternized triethanolamine groups (sold by Onyx Chemical 
Company, Jersey City, NJ, under the name ONAMER M); 
poly(methacrylamidopropyltrimethyl ammonium chloride) obtained by the 
polymerization of the corresponding monomer sold by Texaco Chemical 
Company, Bellaire, TX under the name MAPTAC; and 
quaternized poly(ethyleneimine), quaternized poly(vinylamine), quaternized 
poly-4-vinyl pyridine and the like prepared by methods generally known in 
the art. 
Thus, a useful texturing and strengthening composition of this invention 
can include from zero to about 5 percent by weight of cationic polymer. 
Amounts greater than 5 percent can be employed but are considered 
unnecessary and wasteful. Additionally, the compositions can contain any 
of a variety of cosmetically known adjuvants, including emulsifiers, 
preservatives, viscosity modifying thickeners, auxiliary solvents such as 
alcohols or glycols, proteins, perfume and the like. 
It is recognized that some emulsifiers and some quaternary ammonium 
compounds may have some surface active characteristics useful for 
distributing the composition through the hair during application. However, 
surface active agents typically associated with foaming shampoo products 
are not necessary for practicing the texturing and strengthening aspects 
of this invention. Texturing is independent of any interaction between the 
texturing and strengthening agent and any surface active component and 
does not depend on any co-reaction therebetween. Thus, texturing and 
strengthening compositions are preferably substantially free of 
foam-producing surface active agents. 
In the method of this invention, highly alkaline hair straightener products 
are applied to the hair by methods well known in the art to at least 
partially straighten those portions of the hair that have received no 
prior chemical hair straightening treatment, i.e., substantially virgin 
outgrowth. It is generally well known that the length of time that the 
hair is exposed to a highly alkaline straightener or relaxer product 
varies with the amount of curl in the hair and the strength of the 
alkaline straightening agent. Typically, this length of time is determined 
by the practitioner based on the amount of partial or complete removal of 
natural curl desired. Less than about 20 minutes, preferably less than 
about 15-18 minutes, is desirable. 
For purposes of texturing and strengthening the alkali-treated hair, 
substantially all the hair straightener product is removed from the hair, 
preferably by rinsing with water. Substantially immediately thereafter, a 
post-straightening amount of texturing and strengthening composition is 
applied. For this purpose, the composition has a pH of from between at 
least 8 to about 11, and preferably from between at least pH 8 and about 
pH 9 as described above. The composition is applied in an amount 
sufficient to contact the hair fibers when it is stroked through the hair 
in a gentle downward motion from the scalp to the end portions. A 
sufficient amount was found to be about 1 ounce per average head of hair. 
Surprisingly, we have found that such a post-straightening application of a 
non-acidic composition of this invention having a pH value of at least 8 
or higher had no adverse effect on the physical integrity of such recently 
alkali-treated hair. This finding is contrary to what would normally be 
expected and is contrary to what is presently practiced. Also, surprising, 
we found that hair contacted in this manner for a relatively short time of 
about 5 minutes was simultaneously textured and strengthened and had 
decreased residual alkalinity. 
Residual alkalinity in the alkali-treated hair was measured by sampling the 
hair immediately after rinsing the straightener with water, extracting the 
residue on the hair by soaking the hair sample in water and then measuring 
the pH of the extraction medium as described in Example 3. For comparison, 
the same procedure was followed after the post-straightening texturing 
procedure. Surprisingly, the measurable residual alkalinity of the 
alkali-treated hair was lowered by texturization. 
Auxiliary amounts of the texturing and strengthening agent can be applied 
to the virgin outgrowth before applying the hair straightener. For this 
purpose the texturing and strengthening agent can be provided by the same 
composition having a pH of at least 8 applied in a post-straightening 
procedure. Alternatively, a different non-acidic composition can be used. 
Likewise, the texturing and strengthening agent used in the 
post-straightening step can be the same as or different than that used in 
the pre-straightening step. 
Auxiliary amounts of texturing and strengthening agent can be applied to 
previously straightened outgrowth portions of the hair contained in a 
non-acidic composition to augment texturing benefits. 
Strengthening achieved by the method of this invention is substantially 
complete following the post-straigthening application step. Unlike 
conventional procedures, therefore, the method of this invention does not 
depend on the use of a neutralizing shampoo for strengthening the 
alkali-treated hair. However, the texturizing/strengthening step can be 
followed, if desired, by a shampoo, with or without an intervening water 
rinse. 
Employing a shampoo is usually preferred for purposes of cleansing and 
removing from the hair residual hair straightener, if any, and any excess 
amount of post-straightening composition from the hair or scalp. Any of a 
number of conventional shampoos typically used by practitioners in the 
hair straightening arts can be employed. Typically, such shampoos are 
neutralizing shampoos having an acidic to neutral pH. For purposes of 
practicing the principles of this invention, the type of shampoo employed 
need not be so limited as long as the shampoo components do not interact 
with or inactivate the texturing component in the hair or decrease the 
strength of the hair. The texturing benefits achieved by the method of 
this invention survived through multiple shampoo applications and were 
thus long-lasting effects. 
Texturing and strengthening of the hair is reflected by a discernibly 
improved tactile feel, such as smoothness, silkiness and normally 
associated attributes of conditioning that influence combing, 
manageability, etc., as well as perceived attributes such as luster. It is 
generally recognized that hair condition is a complex concept that depends 
on a variety of physical quantities that are subjectively evaluated by 
practitioners. Thus, some instrumental techniques were also employed to 
measure functional relationships of various physical quantities of 
strengthening associated with subjective hair texturization properties. 
One of the instrumental techniques employed measures the stress-strain 
modulus of hair in terms of fiber elongation and axial swelling while it 
is actually undergoing a chemical straightening procedure. This technique 
is called the intermittent modulus technique because changes in the 
strength of the hair under an intermittently applied additional load are 
measured. For this purpose, a laboratory model of an intermittent modulus 
device was constructed and employed. 
The intermittent modulus device comprises a balance attached to a beam 
which controls illumination of a photocell and generates a current. Light 
control for the photocell is electronically regulated and current is 
measured on a strip chart recorder. 
The instrument balance beam is attached to a test hair fiber. The hair 
fiber is anchored at each end by a vinyl tab and is laterally positioned. 
The lateral position of the fiber is controlled by a micrometer, and 
controls are provided on the instrument to assure exact fiber alignment. 
The length of the hair fiber for convenience is preferably of a gauge 
length of about 1.5 centimeters but is not so limited. A constant load is 
placed on the hair fiber and an additional load is applied at intermittent 
intervals. For example, a constant load of 0.5 grams can be applied, and 
additional loads of 0.5 grams can be applied at 30 second intervals. 
Changes in the length of the fiber cause proportional changes in the 
position of the recorder pen. Fiber axial swelling is influenced and 
controlled by applied chemical treatments thus making it possible to 
assess the treatment in terms of fiber axial swelling. Axial swelling 
changes are magnified 200 times on the recorder chart, so that a 30 
millimeter pen excursion is equivalent to 1 percent change in fiber length 
for a fiber of 1.5 centimeters gauge length. 
Using this technique, therefore, fiber integrity is measured in terms of 
both fiber strength and fiber elongation. Fiber strength is determined by 
the height of the vertical pen excursion. For example, the greater the 
chemical attack, the weaker the fiber will become and this will be 
reflected by a greater vertical excursion by the pen. Fiber elongation is 
related to supercontraction and is reflected by changes in the vertical 
position of the pen on the recorder chart. Thus shortening of the fiber as 
it weakens is readily observable. Restoration of fiber integrity is judged 
as a reversal of weakened fiber strength and supercontraction, i.e., less 
supercontracted. 
From our experience, calculated values of percent loss in tensile strength 
of hair that has been straightened with highly alkaline "lye" or "no-lye" 
relaxers obtained with the intermittent modulus technique compare 
favorably with those obtained by commercially available tensile testers, 
such as the Scott Tensile Tester, GCA/Precision Scientific, Chicago, IL. 
Also in this regard, a description of the construction of a laboratory 
model of an analogous device used to study the performance of depilatories 
can be found in Elliot, "Use of a Laboratory Model to Evaluate the factors 
Influencing the Performance of Depilatories," J. Soc. Cosm. Chem., 25, 367 
(1974). 
This invention is further illustrated in the following Examples, which are 
not intended to be limited. 
EXAMPLE 1 
This example illustrates texturing and strengthening compositions suitable 
for use on hair that is about to under or has just undergo a highly 
alkaline hair straightening procedure. For convenience, the following 
formulae (A-G) contain a preferred texturing and strengthening agent, 
cocodimonium hydrolyzed animal protein (ingredient no. 1), and where 
present, a preferred cationic polymer, polyquaternium 6 (ingredient no. 
2). 
The compositions below are prepared by dispersing ingredients nos. 1-5 in 
water (ingredient 7) at a temperature of about 35 to about 45 degrees C. 
together with relatively slow mechanical agitation until homogeneous, 
cooling relatively quickly to a temperature of about 30 to about 25 
degrees C. and adding ingredient no. 6 to a pH from at least 8 to about 
8.5, preferably between about pH 8.1 and about 8.4. 
______________________________________ 
Active Weight Percent 
(dry solids basis) 
Ingredient A B C D E F G 
______________________________________ 
1. Cocodimonium hydrolyzed 
2.4 2.4 1.2 2.5 5.0 3.5 0.2 
animal protein (Note a) 
2. Polyquaternium 6 (Note b) 
1.2 1.2 -- -- 5.0 0.1 -- 
3. Polysorbate-20 (Note c) 
1.0 -- -- 0.5 -- -- -- 
4. DL-Panthenol -- 1.0 -- -- -- -- -- 
5. Preservative Q.S. 
6. Triethanolamine (85% in 
Q.S. 
water) to pH 8-8.5 
7. Water, deionized, Q.S. 
to 100 Percent 
______________________________________ 
Note a: CTFA adopted name for a coconut dimethyl ammonium derivative of 
hydrolyzed collagen protein sold under the trade name CROQUAT M by Croda, 
Inc., supplied as a 40 percent solution in water, and stated to have an 
approximate molecular weight of 2,500. 
Note b: CTFA adopted name for poly(dimethyldiallyl ammonium chloride) 
corrisponding to the material sold under the trade name MERQUAT100 by 
Merck Chemical Division, Merck & Company, Inc., supplied as a 40 percent 
solution in water, and stated by the manufacturer to have a weight averag 
molecular weight approximately 100,000. 
Note c: CTFA adopted name for polyoxyethylene (20) sorbitan monolaurate, 
nonionic emulsifier. 
EXAMPLE 2 
This example illustrates nonacidic compositions suitable for use in 
applying auxiliary amounts of texturing and strengthening agent to hair 
that is about to undergo a highly alkaline hair straightening procedure. 
For convenience, the same preferred texturing and strengthening agent and 
preferred cationic polymer used in Example 1 are employed. 
______________________________________ 
Active Weight Percent 
(dry solids basis) 
Ingredient H I J K L M N 
______________________________________ 
1. Cocodimonium hydro- 
0.2 0.8 1.2 2.5 1.0 3.5 1.5 
lyzed animal protein 
(Note a, Example 1) 
2. Steartrimonium hydro- 
0.45 0.45 0.45 0.5 0.5 -- -- 
lyzed animal protein 
(Note d) 
3. Dicetyldimonium 
1.5 0.75 0.75 1.5 -- 0.2 -- 
chloride (Note e) 
4. Polyquaternium 6 
0.2 0.4 0.02 0.25 -- 0.1 1.0 
(Note b, Example 1) 
5. Cetearyl Alcohol 
2.0 2.0 2.0 2.0 1.5 0.5 -- 
(and) Ceteareth-20 
(Note f) 
6. Emulsifying Wax-NF 
2.0 2.0 2.0 2.0 -- 1.0 -- 
(Note g) 
7. Propylene glycol 
25.0 25.0 25.0 25.0 -- -- -- 
8. Preservative Q.S. 
9. Water, deionized, 
Q.S. 
to 100 percent 
______________________________________ 
Note d: CTFA adopted name for a stearyltrimethyl ammonium derivative of 
hydrolyzed collagen sold under the trade name CROTEIN Q by Croda, Inc., 
supplied as a 90 percent active powder, and stated to have an approximate 
molecular weight of 12,000. 
Note e: CTFA adopted name for Nhexadecyl-N,N-dimethyl-1-hexadecaminium 
chloride corresponding to the material sold under the trade name ADOGEN 
432 CG by Sherex Chemical Co., Inc. supplied as a 75 percent solution in 
water. 
Note f: CTFA adopted name corresponding to a nonionic emulsifier sold 
under the name Promulgen D by Amerchol Corporation. 
Note g: CTFA adopted name corresponding to a nonionic emulsifier that is 
mixture of higher fatty alcohols and ethylene oxide sold under the trade 
name Polawax Regular by Croda, Inc. 
The compositions are prepared by dispersing all ingredients, except nos. 2 
and 3 in water at a temperature of about 80 degrees C with gentle 
mechanical agitation until homogeneous, cooling the solution relatively 
quickly to about 50 degrees C and adding ingredients no. 2 and 3. 
Mechanical agitation is maintained until the composition has cooled to 
about 25 degree C. 
EXAMPLE 3 
This example illustrates the post-straightening benefit of texturing and 
strengthening hair that has just undergone a highly alkaline hair 
straightening procedure by applying a nonacidic composition of this 
invention without increasing the residual alkalinity of the alkali-treated 
hair. 
For this study, a commercial "no-base" type hair straightener product of 
regular strength containing about 2 to about 2.5 percent sodium hydroxide 
(C) was employed. Eleven female volunteers, each having varying degrees of 
natural curl in their hair had their hair straightened in the following 
procedure. 
Because each of the volunteers had a history of previous chemical 
straightening of their hair, the nonvirgin outgrowth portion was treated 
with a prestraightening auxiliary amount of texturing and strengthening 
composition. The hair was parted into four sections from the forehead to 
the nape and then across the head from ear to ear. Approximately 5 
milliliters of the non-acidic composition H of example 2 was applied to 
each sectioned outgrowth portion and distributed by combing to contact the 
fibers from the start of the outgrowth portion to the tip ends. A total of 
about 1/4 ounce to about 1/2 ounce of compostion was applied to the entire 
head of hair depending on each subject's needs. 
The straightener product was applied to the virgin curly new growth 
portions of the hair in the conventional manner following the 
manufacturer's instructions. For subjects having hair characterized as 
fine, medium and coarse, the respective total contact time with the highly 
alkaline chemical hair straightener was about 13 minutes, about 15 minutes 
and about 18 minutes, respectively. 
When the desired amount of straightening was obtained, the hair was rinsed 
with water thoroughly until substantially all visible traces of the 
straightener product were removed from the hair and scalp. Excess water 
was squeezed from the hair and immediately afterwards, several relatively 
small tresses totaling at least about 250 milligrams (mg) of hair were 
sampled by cutting them from randomly selected scalp areas. The cut 
tresses were pooled, identified as "after relaxer" samples and allowed to 
air dry at ambient room temperature and humidity. 
The hair having just undergone alkali-straightening as well as the 
outgrowth portion was then treated with a post-straightening amount of 
texturing and strengthening agent using composition A of Example 1. This 
composition was clear and had a pH of 8.3. Approximately one ounce of 
texturing composition was applied to the hair and was gently combed 
through from the crown to the nape to contact all portions of the hair 
fibers. After about 5 minutes, several relatively small tresses of hair 
were again randomly sampled as described earlier. The pooled samples were 
identified as "after texturing" and were allowed to air dry at ambient 
room temperature and humidity. Except for the removal of hair samples as 
described above, each of the volunteers had their hair subsequently 
shampooed with a commercial nonalkaline neutralizing shampoo (E) and 
styled as practiced in conventional procedures. The neutralizing shampoo 
contained an amphoteric surfactant and had a pH of about 5.5 to about 6.5. 
The residual alkalinity of the sampled hair identified above was measured 
by soaking the hair in deaerated distilled water and measuring the pH of 
the extraction medium using the following procedure. The deaerated 
distilled water was prepared by boiling distilled water (Hinckley & 
Schmidt) and then cooling it to ambient room temperature just before using 
it. For measuring pH, a Radiometer model TTA60 titration assembly was used 
in conjunction with a Radiometer model PHM64 research pH meter. 
After the hair sampled had dried, it was prepared for pH measurements by 
cutting an individually identified tress into a relatively fine size and 
thoroughly mixing the cutting to obtain a substantially uniformly 
distributed sample. An amount of about 300 to about 500 mg of this finely 
cut hair was accurately weighed into a titration vessel adapted for use 
with the Radiometer titration assembly, covered lightly and set aside 
until needed. This procedure was followed for all tresses obtained, 
retaining each identified sample in separate vessels. For comparison 
purposes, the amount of finely cut hair weighed for measuring the residual 
alkalinity after the relaxer step and after the texturing step was about 
the same, where possible. 
A volumetric amount of 10 milliliters of the distilled water, prepared as 
described above, was pipetted into an empty dry titration vessel, mounted 
on the titration assembly and stirred for 10 minutes. The pH of the water 
was measured at the end of the 10 minutes and recorded. This procedure was 
repeated several times during the course of this study to determine the 
average pH of the water using separate vessels for each measurement. Based 
on these measurements, the average pH value of the water was about 6.18. 
To measure the residual alkalinity of the hair sampled and identified as 
"after relaxer", 10 milliliters of the deaerated distilled water described 
above were volumetrically pipetted into the titration vessel containing 
the accurately weighed finely cut hair sample. This vessel was then 
mounted on the titration assembly and the hair/water mixture was stirred 
for 10 minutes, after which the pH of the extraction medium was measured 
and recorded. The procedure was repeated with a second sample and the 
average pH value of the duplicate samples was determined. The individual 
pH values between duplicates agreed within 0.1 pH unit. This same 
procedure was followed for hair sampled and identified as "after 
texturing." 
The average pH values of the extraction medium obtained from the amount of 
hair sampled taken from each of the eleven volunteers (1-11) are compared 
in the following Table. 
______________________________________ 
Average pH of Medium 
(A) (B) 
Mg After Mg After (A-B) 
Volunteer 
Hair Relaxer Hair Texturing 
Change 
______________________________________ 
1 500 7.62 500 7.16 -0.46 
2 500 8.13 500 7.71 -0.42 
3 337 9.26 339 8.60 -0.66 
4 500 9.12 500 7.70 -1.42 
5 372 8.92 320 7.59 -1.33 
6 500 9.14 500 7.33 -1.81 
7 500 9.26 271 7.37 -1.89 
8 358 9.14 316 8.24 -0.90 
9 309 9.44 401 7.76 -1.68 
10 500 9.30 500 8.40 -0.90 
11 423 7.84 353 7.55 -0.29 
Average 8.83 7.76 -1.07 
______________________________________ 
The overall variation between the pH values obtained for any two separate 
volunteers can be attributed to differences expected for variable rinsing 
times used by the beautician as required for that individual volunteer. 
The results show that the residual alkalinity on the alkali-straightened 
hair was decreased by the texturing and strengthening composition. As 
seen, in all cases the residual alkalinity of the medium for textured hair 
samples (column B) was lower than that of the medium for relaxed hair 
sample (column A), by from 0.29 to 1.89 pH units with a average decrease 
of about one pH unit. Thus, at the end of the texturing and strengthening 
procedure, the alkalinity of the residue on the textured hair was 
substantially neutral (average value of pH 7.76) whereas after the 
relaxer, it was alkaline (average value pH 8.83). 
EXAMPLE 4 
This example illustrates the texturing benefit of the method of this 
invention using a nonacidic texturing and strengthening composition of 
this invention (A) compared to that of an acidic commercial "normalizer" 
product (B) embodying the principles of U.S. Pat. No. 4,602,648. 
The general procedure of Example 3 was followed, except that no hair 
tresses were sampled. For comparison purposes, the same procedure of 
Example 3 was practiced on one side of the head (identified as side A) 
employing composition H of Example 2 as the auxiliary texturing and 
strengthening agent before applying the commercial regular strength 
straightener product (C), and composition B of Example 1 having a pH of 
8.15 as the post-straightening texturing and strengthening composition. 
The amounts applied to the hair were adjusted accordingly as needed. 
On the opposite side of the head (identified as side B) the hair was 
straightened, following the manufacturer's instruction using the regular 
strength hair straightener product component (D) supplied with the acidic 
pre-shampoo normalizer product (B). The amounts applied were adjusted for 
half-head usage. Following instructions, the pre-shampoo normalizer 
product (B) was applied to the hair after rinsing the hair straightener 
product (D) from the hair with water, massaged through the hair gently. 
After a period of about 5 minutes the hair was shampooed. The same 
neutralizing shampoo (E) was employed on both sides of the head. Multiple 
shampoo application of at least two to three were employed, as needed. 
Experienced beauticians evaluated and compared the characteristics of the 
products and the texture and strength of the hair as shown below in a 
study using 50 female volunteer subjects. 
______________________________________ 
Number of Notations 
Characteristic Side A Side B No Diff. 
______________________________________ 
Softer feel on wet hair after 
43 -- 7 
post-straightener treatment 
Easier wet combing after 
44 1 6 
shampooing 
Hair loss (more breakage) 
-- 3 47 
Easier dry combing 
1 -- 44 
Preferred dry feel of hair 
6 -- 40 
More straightening 
7 5 38 
Sheen -- -- 50 
Manageability -- -- 50 
Static flyaway -- -- 50 
Overall preferred 
36 4 10 
Alkali sensation on scalp 
6 13 -- 
______________________________________ 
The results show that applying a texturing and strengthening agent of this 
invention contained in a nonacidic composition to hair about to undergo 
and to hair having just undergone a highly alkaline hair straightening 
procedure provided more discernible conditioning benefits than did a 
commercial product employing an acidic preshampoo normalizer composition. 
These benefits show that the texturing effect survived multiple shampoo 
applications. 
EXAMPLE 5 
This example illustrates the benefit of strengthening hair undergoing a 
highly alkaline hair straightening procedure with nonacidic texturing and 
strengthening compositions of this invention. Strengthening was determined 
by intermittent modulus technique using the intermittent modulus device 
described above. 
For this study, fibers of natural brown-colored intact hair (R. Weintraub, 
New York, NY) of gauge length 1.5 centimeters were individually mounted 
between vinyl tabs. A constant load of 0.5 grams was used with an 
additional intermittent load of 0.5 grams applied at 30 second intervals. 
Restoration of fiber integrity was determined by observing changes in the 
strength and elongation (supercontraction) of the fiber undergoing the 
hair straightening procedure. These changes were recorded on a Heath strip 
chart recorder having a 10 millivolt sensitivity using a chart speed of 
0.1 inches per minute. A 30 millimeter pen excursion for this length fiber 
was equivalent to a 1 percent change in fiber length. For example, the 
strength of the fiber weakened and supercontracted during a relaxer 
treatment as reflected by changes in the vertical position of the pen on 
the chart. Thus, strengthening was determined by observing reversals in 
this pattern, based on proportional changes in the recorder pen position. 
A series of studies were made to observe the strengthening effects of 
applying nonacidic compositions of this invention to the hair at various 
stages of the hair straightening procedure. In all studies, the relaxer 
product used was the commercial regular strength sodium hydroxide 
containing relaxer creme (C) of Example 3, applied as supplied in an 
amount sufficient to coat the fiber, left on the hair to the point where 
maximum supercontraction was recorded (usually about 3 to about 5 
minutes), after which the relaxer was rinsed from the fiber with tap 
water. 
The variations in the process were either in stage (I) where the hair about 
to undergo straightening was pretexturized texturized by applying the 
nonacidic composition H (pH 6.1) of Example 2 immediately before the 
relaxer, or in stage (II) where the hair having just undergone 
straightening was texturized by coating the fiber with nonacidic 
composition A (pH 8.32) of Example 1 for about 5 minutes, or in stage 
(III) where the post-straightening texturization procedure in stage (II) 
was followed by a tap water rinse (WR) or in stage (IV) where the entire 
procedure was terminated by shampooing with the commercial nonalkaline 
neutralizing shampoo (S) of Example 3, except that the shampoo was diluted 
1:9 parts with tap water for convenience. 
These variations are summarized in the following Table in study nos. 1-6. 
For comparison, study nos. 7-9 were included to observe the strengthening 
effects achieved by practicing the principles taught in the '648 patent by 
substituting the commercial acidic normalizer product (N) used in Example 
4 in stage (II). For further comparison, a counterpart to the acidic 
normalizer containing the texturing and strengthening agent of this 
invention (composition T, pH 3.5) was prepared for use in stage (II) shown 
in study no. 10. 
Composition T was prepared following the procedure of Example 1 for 
composition B, except that triethanolamine was omitted and instead 
included 0.5 weight percent boric acid and 0.2 weight percent citric acid 
along with 0.2 weight percent of a polyquaternium 10 having an average 
molecular weight of about 100,000. (Polyquaternium 10 is the CTFA adopted 
name for a polymeric quaternary ammonium salt of hydroxyethyl cellulose 
reacted with a trimethyl ammonium substituted epoxide corresponding in 
this instance to Polymer JR 30M sold by Union Carbide Company.) Each study 
shown in the Table was done in duplicate. The stage performed is shown by 
the alphabetical designation of the composition used while the omission of 
the stage is indicated by a dash. 
______________________________________ 
Study no. Stage I Stage II Stage III 
Stage IV 
______________________________________ 
1 -- -- -- S 
2 -- A WR -- 
3 H -- -- -- 
4 H A WR -- 
5 H -- -- S 
6 H A -- S 
7 -- N -- S 
8 H N WR S 
9 H N WR -- 
10 -- T WR -- 
______________________________________ 
The results showed that water rinsing alkali-straightened hair, in itself, 
strengthens the alkali weakened fiber to a certain extent, and that an 
acidic neutralizing shampoo, as in study no. 1 contributes further to 
producing a less supercontracted, i.e., less rubbery, more springy, fiber. 
This result and study generally agrees with what is conventionally 
practiced and known. 
More importantly, the study also confirmed that the texturing and 
strengthening agent of this invention applied to the hair in stage II 
strengthened the hair and that strengthening was substantially completed 
at the end of stage II. The strengthening achieved was substantially 
equivalent to that provided upon use of an acidic neutralizing shampoo. 
Thus, the neutralizing shampoo step in Stage IV provided no further 
increased strength benefit, based on study nos. 2, 4, and 6. Additionally, 
the strengthening effect obtained was unaffected by rinsing with water 
after the texturing procedure. 
Any measurable benefit of the texturing and strengthening agent on fiber 
properties applied in stage I was generally obscured by the overwhelming 
weakening effect of the relaxer in study nos. 3, 4, 5 and 6. This result 
showed that the nonacidic composition H did not interfere with the 
straightening action of the relaxer even though the measurable pH of 
composition H was inherently mildly acidic (pH 6.1). While this study was 
unable to detect strengthening benefits from applying this particular 
nonacidic composition, we know from experience and the texturing results 
in Example 4 show that composition H contributes to augmenting the 
texturing effect on the hair. 
The texturing and strengthening agent of this invention generally showed a 
pattern of strengthening seen on the recorder as a gradual increase in 
fiber length that leveled off when complete. Thus, while the mechanism is 
not fully understood, the result suggests that the cation receptive 
negative sites in the hair are sustained while the nonacidic composition 
of this invention simultaneously strengthens and texturizes the hair in 
stage II. A similar gradual pattern was seen in study no. 10 where the 
composition was purposely acidified. The result confirms that 
strengthening is substantially as effective as an acidic neutralizer. 
This observation was further confirmed when the commercial normalizer 
product N was used instead in stage II in study nos. 7-9. The pH of this 
product was measured as pH 4.6. Unlike the nonacidic texturing and 
straightening compositions of this invention, product N reversed 
supercontraction of the relaxed hair relatively rapidly but strengthening 
overall was not superior to that obtained with the strengthening agent in 
composition A of the invention. This result suggests that the acid 
components in product N deswell the fiber rapidly owing to acid 
neutralization of the alkaline residue on the hair as one would expect. 
However, any benefit achieved from such rapid reversal in terms of lasting 
conditioning was not observed as shown in Example 4. 
In another study, the procedure of study no. 5 was repeated except the 
commercial regular strength relaxer used contained a cationic polymer 
along with sodium hydroxide (CP). Strengthening effects observed were 
similar to those of Study no. 5. 
EXAMPLE 6 
This example illustrates nonacidic compositions having a pH of at least 8 
to about 8.5 suitable for use in applying texturing and strengthening 
agent in an auxiliary amount in a pre-straightening step or in a 
post-straightening step or in both steps to hair undergoing an alkaline 
hair straightening procedure. 
______________________________________ 
Active Weight Percent 
(dry solids basis) 
Ingredient O P Q R S T 
______________________________________ 
1. Cocodimonium hyd- 
-- 2.4 2.4 2.4 2.0 -- 
rolyzed animal pro- 
tein (Note a, 
Example 1) 
2. Steartrimonium hyd- 
2.4 0.9 0.9 0.9 1.0 -- 
rolyzed animal protein 
(Note d, Example 2) 
3. Dicetyldimonium 
-- 1.5 1.5 1.5 1.5 1.5 
chloride (Note e, 
Example 2) 
4. Polyquaternium 6 
1.2 1.2 1.2 1.2 1.0 1.5 
(Note b, Example 1) 
5. N-soya-N-ethyl mor- 
-- 0.5 -- -- -- 0.5 
pholinium ethosulfate 
(Note h) 
6. Hydrolyzed animal 
-- 2.2 2.2 -- -- -- 
protein (Note i) 
7. Cetearyl Alcohol 
(and) Ceteareth-20 
-- 2.0 2.0 2.0 2.0 2.0 
(Note e, Example 2) 
8. Emulsifying Wax-NF 
-- 2.0 2.0 2.0 2.0 2.0 
(Note f, Example 2) 
9. Stearic Acid -- 1.5 -- -- 1.0 1.5 
10. Propylene glycol 
-- 15.0 -- -- 10.0 15.0 
11. Preservative Q.S. 
12. Thickener Q.S. -- Q.S. Q.S Q.S Q.S 
13. Triethanolamine (85% 
Q.S. 
in water) to pH 8-8.5 
14. Water, deionized 
Q.S. 
to 100 percent 
______________________________________ 
Note h: Such as ATLAS G271 sold by ICI Americas, Inc. as a 35 percent 
aqueous solution. 
Note i: CTFA adopted name for a hydrolyzed animal protein sold under the 
trade name LEXEIN X250 by Inolex Chemical Company, supplied as a 55 
percent aqueous solution. 
EXAMPLE 7 
This example illustrates the benefit of strengthening hair undergoing a 
highly alkaline hair straightening procedure with non-acidic texturing and 
strengthening compositions of this invention applied in a texturing 
procedure practiced in a pre-straightening step and in a 
post-straightening step. Strengthening was determined by tensile wet break 
strength technique as described below. 
For this study (No. 1) a 5-inch tress of natural dark brown hair (DeMeo 
Brothers, New York, NY) 2 grams in weight was used. To this tress, 5 grams 
of the commercial regular strength hair straightener C used in Example 3 
was applied. After 18 minutes, the hair straightener was removed by 
thoroughly rinsing the hair tress using warm tap water (Stage 1). The 
texturing and straightening composition A of Example 1 was applied in an 
amount of 1 gram to the rinsed straightened hair. After 5 minutes, the 
composition was rinsed from the hair using warm tap water (Stage 2). 
The tensile wet elongation and break strength of the textured tress was 
determined by removing 25 fibers from the tress after Stage 1 and again 
after Stage 2. The fibers were equilibrated in water overnight. The gram 
force required to break the wet fiber under elongation while submerged in 
water was measured using the Scott Tensile Tester, and mean break force 
determined. For comparison, fibers from an untreated tress were similarly 
tested as a control. 
In another study (No. 2), the procedure of study No. 1 was repeated, 
excepted that 0.5 grams of auxiliary texturing and straightening 
composition B of Example 2, was also applied to the tress immediately 
before applying the hair straightener. 
For comparison a regular straightening procedure was practiced in a a third 
study (No. 3) in which 5 grams of the commercial regular strength hair 
straightener containing cationic polymer CP used in Example 3 was applied 
to a similar tress and the procedure of Study No. 1 up to Stage 1 
otherwise followed. After rinsing the hair straightener from the hair the 
straightened hair was shampooed using two sudsings with the non-alkaline 
neutralizing shampoo E of Example 3, rinsing thoroughly (Stage 3). The 
results in the following table show the percent decrease in strength after 
straightening (Stage 1), and either after post-straightening tensile 
texturing (Stage 2) or after neutralizing (Stage 3) and the percent regain 
in original pre-straightened strength. 
______________________________________ 
A B 
Mean Percent Percent 
Tensile Gram 
Decrease Regain 
Study No. Break Force 
in Strength 
in Strength 
______________________________________ 
1 (Stage 1) 43.48 -17.79 -- 
1 (Stage 2) 50.48 -4.55 75 
2 (Stage 1) 47.87 -9.46 -- 
2 (Stage 2) 53.00 +0.21 100 
3 (Stage 1) 44.09 -16.64 -- 
3 (Stage 3) 48.82 -7.70 50 
Untreated (Control) 
52.9 -- 0 
______________________________________ 
The data were found statistically significant at a confidence level of 95 
percent when subjected to a Standard Statistical T-Test Analysis. 
The break strength results of Study No. 1 showed that the texturing 
compositions of this invention restored tensile strength to the 
alkali-straightened hair to a level approaching the original 
pre-straightened level when applied in a post-straightening procedure. In 
study No. 2, the original tensile strength of the hair was substantially 
regained when auxiliary texturing composition was applied in a 
pre-straightening step as well. This finding showed that the texturing 
procedure provided a lasting protective effect. 
By applying auxiliary texturing composition before straightening, the 
decrease in tensile strength caused by the alkaline hair straightener was 
lessened by about 8.33 percent comparing stages 1 of Studies No. 1 and No. 
2. 
The results further show that the texturing and strengthening compositions 
in the method of this invention restored tensile strength to a greater 
extent than was restored by a non-alkaline neutralizing shampoo in Study 
No. 3. 
The present invention has been described with respect to preferred 
embodiments. It will be clear to those skilled in the art that 
modifications and/or variations of the disclosed compositions and methods 
can be made without departing from the scope of the invention set forth 
herein.