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Description  |
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BACKGROUND OF THE INVENTION
1. Field of Invention
This invention relates broadly to a hair waving or curling process and a
novel rearranging waving lotion composition for use in a waving or curling
process.
2. Prior Art
Among the components of hair is a proteinaceous material called "keratin".
The hair's keratin is made up of long fibrous polypeptide chains which are
bonded together with horizontal cross bonds of two forms: Hydrogen bonds
and cystine bonds, also sometimes referred to as disulfide bonds.
Cystine bonds play an essential role in determining the degree of curl in
hair. Some researchers in the field believe that straight or slightly wavy
hair has relatively fewer cystine bonds and relies heavily upon hydrogen
bonding to produce curl or waves in the hair and that very curly hair has
a relatively larger amount of cystine bonds. Other researchers in the
field believe that straight hair and curly hair may have the same number
of cystine bonds, but that the cystine bonds present in straight hair tend
to occur in a relatively straight alignment, whereas the cystine bonds
present in curly hair tend to occur out of alignment. Regardless of which
theory is accepted, while the hydrogen bonds can be broken merely by
wetting the hair, such that straight or slightly wavy hair will lose
virtually all body when wet, very curly hair maintains its body even when
wet because the cystine bonds are relatively unaffected by water. Thus,
very curly hair cannot be easily reset into new or different hair styles
different from its natural state merely by wetting and shaping the hair.
Permanent hair waving is usually carried out by subjecting the hair to a
strong reducing agent, such as hydroxide or, more commonly, materials
containing a free "--SH" group or thiol. These "thiol" materials are also
called mercaptans. In this treatment, the hair is saturated with the thiol
agent, which then acts to break the disulfide bonds.
When a sufficient number of hair disulfide bonds habe been broken, the hair
is rinsed, removing the unreacted thiol waving agent and disulfide
reaction product. The hair is then realigned, e.g., usually by winding on
rollers, in order to physically align previously unpaired hair protein
bonds, i.e., one-half of the cystine groups. The hair and rollers are then
saturated with an oxidizing agent, or neutralizer, such as hydrogen
peroxide or a bromate salt, to reform disulfide bonds between the newly
paired hair protein thiols and to give the hair a configuration of wave.
This general process may be used to either add curl or straighten the
hair.
Salts of thioglycolic acid, such as ammonium thioglycolate, and
thioglycolic acid esters, such as glycerol thioglycolate, are typically
utilized as the thiol waving agent. Other thiol-containing reagents such
as thiolactic acid, betamercaptopropionic acid, beta-mercaptobutyric acid,
mercaptosuccinic acid and alike have been suggested in the art to be
effective.
Prior art waving processes are plagued with the problem of either
underwaving or overwaving (under or over processing) that occurs during
waving on different parts of a single hair fiber or different areas of the
hair mass due to the physical or chemical condition of the hair itself.
For example, hair which has been waved, or bleached, or both is more
porous than hair which has not undergone these chemical treatments, e.g.,
portions of the hair fiber near the hair root which has grown out since
the last bleaching or waving. Similarly, even hair having no previous
history of bleaching or waving is more porous near the tip end than near
the root end simply because hair near the tip has been brushed more, or
has been subjected to more weathering.
As a consequence of these porosity differences, the hair tends to take up
more waving agent in some areas and less waving agent in others. Over
waving or processing tends to occur in the more porous portions of the
hair while underwaving or processing tends to occur in less porous areas.
These trends are exactly the inverse of what is desired since the hair
which usually need the waving treatment the most gets the least waving,
and visa versa.
Many products today are directed to the special problems and needs of the
Black ethnic market. People in the Black ethnic market have, for example,
hair characterized by a relatively large number of cystine bonds and
relatively high dryness. Conventional permanent waving products have
particular limitations applied to this market. Typically, the products
result in a hair style that is either very curly and quite greasy or
relatively straight and stiff and very dry. These prior products are
characterized by the need for frequent, heavy maintenance, e.g., the
consumer's application of activators and moisturizers on a daily basis or
more than daily basis. None of the prior art compounds are able to produce
a Black ethnic hairstyle characterized by thick, full-bodied hair fibers
which form loose bouncy curls having good moisture retention.
One of the problems associated with prior art permanent waving process is
that they dry the hair to a substantial degree. This problem becomes
particularly significant for hair that is relatively dry to begin with. As
a result, the prior art processes are associated with with need for
frequent and repeated use of moisturizers to maintain the hair. This
problem is both inconvenient and expensive for the consumer. It also
imposes limitations on the type of hair style that may be achieved with
prior waving processes.
Another problem that occurs during the hair disulfide bond breaking process
is skin irritation caused by the thiol-containing agents. Irritation
occurs usually because beauticians frequently use their bare fingers for
the wrapping process.
All of the known waving processes and solutions associated therewith are
limited in their ability to produce a looser, bouncier, curl while
maintaining the moisture of the curls. The present invention provides an
improved in hair waving process, eliminating many of the problems
associated with prior art processes and solutions.
SUMMARY OF THE INVENTION
Thus, an object of the present invention is to provide an improved hair
waving process and further to provide an improved rearranger composition
for use in a hair waving process.
It is an object of this invention to provide a permanent waving process and
rearranger that produces hair with improved humectant qualities and that
requires less maintenance.
Accordingly, in a broad embodiment, the present invention is a process of
waving hair by applying to the hair a particular rearranging composition
with chemical properties sufficient to change the alignment of the cystine
bonds in the hair keratin. After the rearranger has been left on the hair
for a time to accomplish conversion of the bonds, the hair is rinsed to
flush away a substantial portion of the rearranging composition. The
rearranging composition comprises a homogenous mixture of a salt of
thioglycolic acid and a cationic homopolymer of
methylacrylamidopropyltrimethyl ammonium chloride. A wrapping lotion
composition is then applied to the hair. The hair, with wrapping lotion
applied, is wrapped around a rod or roller to produce a desired curl
pattern. The hair with wrapping lotion applied is left on the rods for a
predetermined length of time, preferably about 5 to about 15 minutes, in
order to set or lock in the desired curl pattern. The wrapped hair is
rinsed to flush away excess wrapping lotion composition.
After rinsing, a neutralizer composition is applied to the hair, still on
the rods, to lock in the curl pattern. The neutralizer is left on the hair
for a sufficient period of time to reestablish the cystine bonds, after
which the neutralizer is flushed away by rinsing the hair.
The improved rearranger comprises a salt of thioglycolatic acid and between
about 1.00 and about 3.0% by weight of a cationic homopolymer of
methacrylamidopropyltrimethyl ammonium chloride. In preferred form the
rearranger also includes between about 6.0 and about 10.0% by weight of
ammonium thioglycolate, between about 3.0 and about 7.0% by weight of
monoethanolamine thioglycolate. Also, in preferred form, the rearranger
has a pH of between about 8.0 and about 10.5.
These as well as other objects and embodiments will become apparent upon
review of the more detailed description of the invention hereinafter set
forth.
DETAILED DESCRIPTION OF THE INVENTION
The waving process of the instant invention is comprised of several steps,
some of which involve the application of specific hair treatment
formulations. As a first step, a rearranging composition is applied to the
hair to perform a straightening function. The rearranging composition
contains an aqueous solution of chemical agents capable of reducing the
disulfide linkages in hair keratin. Suitable chemical agents include water
soluable mercaptans, e.g. salts of thioglycolic acid, such as sodium,
monoethanolamine, or ammonium thioglycolate, and magnesium thioglycolate.
Other soluble mercaptans include thioglycerol, sodium or potassium
borohydride, and sodium or ammonium sulfite. The amount of these chemical
agents may vary depending on, among other things, the degree of
straightening desired, hair treatment history, and the chemical nature of
the particular hair to be treated.
A preferred rearranging composition comprises a mixture of ammonium
thioglycolate and monoethanolamine thioglycolate ("MEA-Thio"). However, it
is within the scope of the invention that either thioglycolate compound
may be used alone or as a substitute for the other. When a mixture of the
two is used, the ammonium thioglycolate is preferably present
inconcentration ranges of about 6.0 to about 10.0% by weight of the
rearranging composition, and the MEA-Thio is preferably present in
concentrations of about 3.0 to about 7.0% by weight of the total
composition. The ammonium thioglycolate and MEA-Thio together preferably
comprise between about 7.0% and about 16.0% by weight of the total
rearranger composition. A most preferred rearranging composition comprises
about 8.0% by weight of ammonium thioglycolate and about 5.5% by weight
MEA-Thio. Alternatively, the rearranging composition may be characterized
by the weight ratio of ammonium thioglycolate to MEA-Thio. A preferred
ratio is between about 4:6 about 7:3 ammonium thioglycolate to MEA-Thio,
with a most preferred ratio of 6:4. When only one salt of thioglycolic
acid is used, the preferred concentration is between about 5.0 and about
20% by weight. Additionally, a variety of conventional additives may be
present in the rearranging composition, such as, conditioners perfumes,
emollients, etc. The pH of the composition is adjusted to between 8.0 and
10.5, preferably using ammonium hydroxide. Surprisingly and unexpectedly
it has been found that the addition of a polyquaternary amine salt to the
rearranging composition has a significant affect on the quality and
settability of the hair both during and long after the waving process. The
preferred polyquaternary amine salt is a highly charge cationic
homopolymer of methacrylamidopropyltrimethyl ammonium chloride (MAPTAC). A
preferred concentration of MAPTAC is from between about 1.0 to about 3.0%
by weight of the rearranging composition, with a most preferred
concentration of about 2.0% by weight. The average molecular weight of the
MAPTAC homopolymer ranges from about 100,000 to about 200,000.
Although not completely understood it is believed that the MAPTAC increases
the longevity of the curl pattern and the humectant qualities of the hair
by penetrating the hair. When the neutralizer solution is applied the
polymer is believed to become "locked" into the hair. The increased
integrity of the hair and the curl pattern that results from the
application of MAPTAC greatly reduces the need for maintenance between
subsequent waving treatments.
Additionally, a variety of conventional additives may be present in the
rearranging composition, such as, conditioners, perfumes, moisturizers,
emollients, etc. The pH of the composition is adjusted to between 8.0 and
10.5 using, preferably, ammonium hydroxide.
The rearranging composition is initially applied to the head and worked
into the hair with gentle combing. The rearranging composition is allowed
to stand, on the hair for about 5-15 or 20 minutes while the cystine bonds
are being broken, the length of time the rearranger is allowed to stand
depends upon the degree of curl in the hair's natural state and the degree
of straightness desired.
After the hair has straightened to the desired degree, the hair is rinsed,
preferably with warm water for about 3-5 minutes to flush away the major
portion, preferably all, of the rearranging composition. In this way, the
rearranging composition and the wrapping lotion composition are not
applied to the hair at the same time.
After the hair has been rinsed, a wrapping lotion or booster is applied to
the head and gently massaged into the hair. The hair is then wrapped on
rods, curlers, rollers or any other means known to the art to produce or
establish a desired curl pattern. The wrapped hair containing the wrapping
lotion is allowed to stand for a period of about 5-15 minutes, while the
pattern of the curl becomes set. The advantages of the rearranger
disclosed herein are believed to occur even if the rearranger is used with
any conventional wave wrapping lotion or booster.
After the wrapping lotion has been allowed to stand on the wrapped hair for
a period of about 5 to about 15 minutes, the wrapped hair is then rinsed
with warm water to remove any excess of wrapping lotion composition.
After rinsing, a neutralizer is applied to the wrapped hair to restore the
disulfide linkages in the hair keratin. The neutralizer "locks in" the
curl pattern that was formed in the previous steps of the waving process.
The exact composition of the neutralizer is not believed critical to
achieve the improved results obtained by the waving process of the
invention. As known to the art, neutralizers are typically aqueous
solutions containing oxidizing agents, such as, sodium bromate. Other
ingredients may be added to the neutralizer composition to improve the
aesthetic properties of the hair. In particular, it has been found that
the addition of from about 1.0 to about 5.0% by weight of ethoxylated
castor oil greatly improves the sheen quality of the hair.
After application of the neutralizer, the wrapped hair is then rinsed with
warm water to remove a substantial portion, preferably all, of the
neutralizer composition. The rods are then removed and the hair is again
rinsed with water. As an optional post-treatment step a sealer may be
applied to the hair to alleviate the initial dryness that sometimes
results immediately after the hair has undergone a waving process. Well
known to the art, sealers contain conditioners and humectants.
In order to more fully demonstrate the attendant advantages arising from
the present invention, the following examples are set forth. It is to be
understood that the following is by way of example of only and is not
intended as an undue limitation on the otherwise broad scope of invention.
EXAMPLE I
In accordance with the invention a rearranging composition was prepared for
use and evaluation in a waving process. A first solution was prepared by
combining and mixing deionized water and a cationic homopolymer of MAPTAC.
This solution was then heated to about 80.degree. C. A second soultion of
surfactants, conditioners and moisturizers was prepared and heated to
about 80.degree. C. The second solution was combined with the first
solution and mixed for about 20 minutes and the resultant admixture was
allowed to cool to about 50.degree. C. A third solution of
monoethanolamine thioglycolate, fragrance and a pH adjuster was then added
to the admixture and mixed slowly until a homogenous solution was
obtained. The relative weight fractions of the components in the
composition, designated as formulation A, are listed in Table II.
TABLE I
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Formulation A
Formulation B
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Deionized H.sub.2 O
59.7 59.6
MAPTAC 2.0 --
Ammonium Thioglycolate
8.0 10.0
MEA Thioglycolate
5.5 --
Other Ingredients.sup.1
24.8 30.4
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.sup.1 Conditioners, surfactants, pH adjusters, moisturizers and
fragrance.
EXAMPLE II
For comparison to the rearranging composition of the invention a
conventional prior art rearranger was prepared. The procedure used to make
the prior art rearranger was exactly the same as that used to prepare the
rearranger of the invention described in Example I, with the exception of
the homopolymer of MAPTAC. Additionally, only ammonium thioglycolate was
used as the active salt of thioglycolic acid. The absence of MEA
thioglycolate did not affect the validity of the comparison. Table I
contains the relative weight fractions of the prior art rearranger,
designated as formulation B.
EXAMPLE III
A waving process in accordance with the invention was performed using the
rearranging composition of Example I. The first step in the process
involved preshampooing the head with a suitable conditioning shampoo. The
hair was then towel blotted dry. The rearranging composition of Example I
was then applied to the hair by a tint-brush procedure in an effect to
minimize scalp irritation. The rearranger used comprised a homogenous
mixture of MEA thioglycolate and a homopolymer of MAPTAC. The rearranger
was allowed to stand on the hair for about 10 to 15 minutes until
straight.
After the processing with the rearranger was completed the hair was rinsed
thoroughly for about 3 to 5 minutes with warm water, then towel blotted
dry. A wrapping lotion was then applied in 1/4 head sections. The hair in
each 1/4 section was then wrapped on rods to produce a curl pattern. After
roding, the wrapping lotion was allowed to stand on the hair for about 10
minutes.
The hair with the rods intact was then rinsed thoroughly with warm water
and then towel blotted dry.
A conventional neutralizer solution having sodium bromate as the active
ingredient was then applied sparingly to each rodded portion of hair and
allowed to stand for about 10 minutes under a plastic wrap. After
processing with the neutralizer, the rodded hair was then rinsed well with
warm water for about 3 to 5 minutes to substantially remove the
neutralizer. The hair was then unrodded, rinsed again, and dried under a
conventional hair dryer.
The resultant hair style obtained from the waving process of the instant
invention was characterized as being thicker, more full bodied than hair
styles previously possible using prior art waving process. In addition,
the longevity of the curl pattern produced and humectant qualities of the
hair was increased on a relatively long term bases with substantially
lower need for application of maintenance products. The improved hair
characteristics obtained as a result of the instant process is believe
directly attributable to the use of the improved rearranging composition
containing the homopolymer of MAPTAC.
EXAMPLE IV
For the purposes of comparison to the improved waving process of the
invention as described in Example III, a conventional prior art waving
process was performed. The procedure used for the conventional waving
process was identical to that of the waving process of Example III with
the exception that the rearranger used did not contain a homopolymer of
MAPTAC. The rearranger used was the formulation described above in Example
II.
The resultant hair style obtained from the conventional waving process was
characterized as relatively tightly curled, dry, and frizzy in appearance.
Furthermore, this style required the application of maintenance products,
such as, moisturizers and curl activators. These maintenance caused an
overall greasy look of the hair style.
The foregoing examples and specification disclose preferred and generalized
illustrations if the invention. However, variations are possible within
the scope of the invention. For example, the rearranger of this invention
is believed to provide advantages when used with any wave wrapping lotion,
booster or neutralizer. It should be understood, therefore, that the
invention is to be limited only by the following claims and their
equivalents.
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