Note: Descriptions are shown in the official language in which they were submitted.
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CLEANSING COMPOSITIONS
TECHNICAL IELD
The present invention relates to cleansing compositions. In particular it
relates to mild personal cleansing compositions with good skin feel
attributes,
rheological behaviour and foaming properties which are suitable for
simultaneously cleansing and conditioning the skin and/or the hair and which
may be used, for example, in the form of foam bath preparations, shower
products, skin cleansers, hand, face and body cleansers, shampoos, etc.
background Of The Invention
Mild cosmetic compositions must satisfy a number of criteria including
cleansing power, foaming properties and mildness/low irritancy/good feel with
respect to the skin, hair and the ocular mucosae. Skin is made up of several
layers of cells which coat and protect the keratin and collagen fibrous
proteins
that form the skeleton of its structure. The outermost of these layers,
referred
to as the stratum corneum, is known to be composed of 250 A protein bundles
surrounded by 80 A thick layers. Hair similarly has a protective outer coating
enclosing the hair fibre which is called the cuticle. Anionic surfactants can
penetrate the stratum corneum membrane and the cuticle and, by delipidization
destroy membrane integrity. This interference with skin and hair protective
membranes can lead to a rough skin feel and eye irritation and may eventually
permit the surfactant to interact with the keratin and hair proteins creating
irritation and loss of barrier and water retention functions.
Ideal cosmetic cleansers should cleanse the skin or hair gently, without
defatting andlor drying the hair and skin and without irritating the ocular
mucosae or leaving skin taut after frequent use. Most lathering soaps, shower
and bath products, shampoos and bars fail in this respect.
Certain synthetic surfactants are known to be mild. However, a major
drawback of most mild synthetic surfactant systems when formulated for
shampooing or personal cleansing is poor lather performance compared to the
highest shampoo and bar soap standards. Thus, surfactants that are among
the mildest are marginal in lather. The use of known high sudsing anionic
surfactants with lather boosters, on the other hand, can yield acceptable
lather
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volume and quality but at the expense of clinical skin mildness. These two
facts make the surfactant selection, the lather and mildness benefit
formulation
process a delicate balancing act.
In addition to the cleansing and lathering performance attributes desired
by consumers it is of particular value that personal cleansing products
further
deliver certain in-use rheological properties. In particular a shower gel
product
which is capable of demonstrating shear thinning behaviour during application
to the skin is preferred by consumers. It is known that water soluble polymers
can be used to provide product thickening attributes and furthermore that
hydrophobically modified water soluble polymers can exhibit enhanced product
thickening behaviour and impart shear thinning characteristics. However it is
also known that such product thickening I shear thinning effects are affected
by
the total surfactant level present in the system and in fact the thickening /
thinning attributes can be significantly diminished in the presence of even
very
low levels of water soluble surfactants. A secondary effect of high surfactant
and electrolyte concentration in systems containing hydrophobically modified
water soluble polymers (HMWSPs) is that at increased surfactant levels the
HMWSP can become increasingly insoluble in the product matrix.
Thus a need exists for personal cleansing products which deliver
acceptable in-use skin feel characteristics but which will not dehydrate the
skin
or result in loss of skin suppleness, which will provide a level of skin
conditioning performance in a wash and rinse-off product which previously has
only been provided by a separate post-cleansing cosmetic moisturizer, which
demonstrate desirable in-use rheology behaviour and which will produce a
foam which is stable and of high quality, which are effective hair and skin
cleansers, which have good rinsibility characteristics, and which at the same
time have stable product and viscosity characteristics and remain fully stable
under long term and stressed temperature storage conditions.
Nonionic water-soluble~cellulose ethers are employed in a variety of
applications, including hair care compositions. Widely used, commercially-
available nonionic cellulose ethers include methyl cellulose, hydroxy propyl
methyl cellulose, hydroxyethylcellulose, hydroxypropyl cellulose and ethyl
hydroxyethyl cellulose.
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Certain modified cellulose ethers have been disclosed in US-A- 4,228,277,
Landoll, issued October 14, 1980, which are relatively low molecular weight
but
which are capable of producing highly viscous aqueous solutions in practical
concentrations. These materials are nonionic cellulose ethers having a
sufficient degree of nonionic substitution selected from the group consisting
of
methyl, hydroxyethyl, and hydroxypropyl to cause them to be water-soluble and
which are further substituted with a hydrocarbon radical having from 10 to 24
carbon atoms in an amount between 0.2 weight percent and the amount which
renders said cellulose ether less than 1 %, by weight, soluble in water. The
cellulose ether to be modified is preferably one of low to medium molecular
weight; i.e., less than 800,000 and preferably between 20,000 and 700,000 (75
to 2500 D.P.).
Modified-cellulose ethers have been-disclosed-for use-in a variety-of
composition types. Landoll ('277) teaches the use of certain materials in
shampoo formulations. Hercules trade literature teaches the use of modified
cellulose ethers materials in shampoos, liquid soaps, and lotions. US-A-
4,683,004 discloses the use of modified cellusoe ethers in mousse
compositions for the hair. US-A- 4,485,089 teaches dentifrice compositions
containing modified cellulose ethers.
It has now been found that personal cleansing compositions having
improved skin feel and moisturisation attributes, both in use and after use,
which deliver desirable thickening / thinning (theology) benefits and good
product stability can be formed by the combination of certain modified
cellulose
ethers, cationic polymers and surfactants. It has also been found that certain
modified cellulose ethers having specified degrees of substitution and chain
lengths confer particular benefits in personal cleansing compositions in terms
of stability and application characteristics.
The subject of the present invention is a mild, foam-producing shear
thinning, stable cleansing product suitable for personal cleansing of the skin
or
hair and which may be used as foam bath and shower products, skin cleansers
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and shampoos etc. According to one aspect of the invention, there is provided
a liquid personal cleansing composition comprising:
(a) from about 5% to about 60% by weight of water-soluble surfactant
selected from anionic, nonionic, zwitterionic and amphoteric
surfactants and mixtures thereof;
(b) from about 0.01 % to about 10% by weight of a hydrophobically
modified nonionic cellulose ether selected from C10-C24 alkyl and
alkenyl modified methyl, hydroxyethyl and hydroxypropyl cellulose
ethers having a degree of nonionic substitution in the range of
from about 1.8 to about 4 and a degree of hydrophobic
substitution in the range of from about 0.1 % to about 1 % by
weight;
(c) from about 0% to about 10% by weight of water-soluble polyol;
(d) from about 0.01% to about 5% by weight of cationic polymeric
skin conditioning agent; and
(e) water
The composition preferably displays a shear stress of about 150Pa at a shear
rate in the range from about 100s-1 to about 600s-1 more preferably from about
400s-1 to about 600s-1 at 25°C.
According to another aspect of the invention there is provided a personal
cleansing composition comprising:
a) from about 5% to about 60% by weight of water-soluble surfactant
selected from anionic, nonionic and amphoteric surfactants and
mixtures thereof;
(b) from about 0.01 % to about 10% by weight of a hydrophobically
modified nonionic cellulose ether selected from C14-C1g alkyl and
alkenyl modified, hydroxyethyl cellulose ethers having a degree
of nonionic substitution in the range of from about 2.2 to about 2.8
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and a degree of hydrophobic substitution in the range of from
about 0.4% to about 6% by weight; and
(c) water.
Such composition preferably displays a shear stress of about 150Pa at a shear
rate in the range from about 400s-1 to about 600s-1 at 25°C.
In a highly preferred embodiment, the invention takes the form of a foam
producing liquid cleansing composition with superior skin feet and rinsing
characteristics, excellent rheological behaviour, improved perceived dryness
and expertly graded dryness and skin hydration measurements and traps
epidemal water loss (TEWL), combined with excellent lathering, good stability,
cleansing ability and conditioning performance.
All concentrations and ratios herein are by weight of the cleansing
composition, unless otherwise specified. Surfactant chain lengths are also on
a
weight average chain length basis, unless otherwise specified.
The liquid cleansing compositions herein are based on a combination of
mild surfactants with certain hydrophobically modified cellulose ethers and
polymeric skin conditioning agents. Preferred embodiments also contain
perfume or cosmetic oils.
The compositions of the present invention contain, as an essential
component, a hydrophobically modified cellulose ether as rheology modifying
agent.
The cellulose ethers prior to hydrophobic modification have a degree of
nonionic substitution in the range from about 1.8 to about 4.0, preferably
from
about 2 to about 3, and especially from about 2.2 to about 2.8. The cellulose
ethers are then further substituted with alkyl or alkenyl groups having 10 to
24,
preferably from about 14 to 18 carbon atoms in an amount from about 0.1 to
about 1, preferably from about 0.3 to about 0.8, and especially from about 0.4
to about 0.6 weight percent. The cellulose ether to be modified is preferably
one of low to medium molecular weight, i.e., less than 800,000 and preferably
between 20,000 and 700,000 (75 to 2500 D.P.).
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The preferred cellulose ether substrate is hydroxyethyf cellulose (HEC) of
50,000 to 700,000 molecular weight. Hydroxyethyl cellulose of this molecular
weight level is the most hydrophilic of the materials completed. Accordingly,
control of the modification process and control of the properties of the
modified
product can be more precise with this substrate. Hydrophiiicity of the most
commonly used nonionic cellulose ethers varies in the general direction:
hydroxyethyl > hydroxypropyl > .hydroxypropyl methyl > methyl.
The long chain alkyl modifier can be attached to the cellulose ether
substrate via an ether, ester or urethane linkage. The ether linkage is
preferred. Although the modified cellulose ether materials are referred to as
being "alkyl modified ", (the term alkyl as used generally herein also
includes
using alkenyl) it will be recognized that except in the case where
modification is
effected with an alkyl halide, the modifier is not a simple long chain alkyl
group.
The group is actually an alphahydroxyalkyl radical in the case of an epoxide,
a
urethane radical in the case of an isocyanate, or an acyl radical in the case
of
an acid or acyl chloride. General methods for making modified cellulose ethers
are taught in Landoll ('277) at column 2, lines 36-fi5.
Modified cellulose ethers of defined substitution levels and hydrophobic
chain length have been found to be particularly desirable for use as theology
modifiers in the personal cleansing compositions of the present invention. The
materials are able to stabilize suspension of dispersed phases, and when used
with the additional components in the compositions of the present invention,
they produce theologically thick products which display desirable shear
thinning
behaviour in-use. In addition, the combination of hydrophobically modified
cellulose ethers with cationic polymeric skin conditioning agents have also
been
found to be particularly beneficial from the viewpoint of viscosity
enhancement
combined with shear-thinning behaviour during application to the skin or hair.
The theology modifying agents for use herein are selected from
hydrophobically modified water-soluble polymers and in particular from
hydrophobicalfy modified hydroxy ethyl cellulose polymers. Suitable
hydrophobically modified hydroxy ethyl cellulose (HMHEC) polymers have a 1
aqueous viscosity in the range of from about 8,000 to about 13,000 mPas
(Brookfield LVT viscometer, spindle No. 4, speed 4).
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WO 96/17916 PCT/US95/15722
One commercially available material suitable for use herein is
NATROSOL PLUS Grade 330 CS (RTM), a hydrophobically modified
hydroxyethylcellulose available from Aqualon Company, Wilmington, Delaware.
This material has a C16 alkyl substitution of from 0.4% to 0.8% by weight. The
hydroxyethyl molar substitution for this material is from 3.0 to 3.7. The
average
molecular weight for the water-soluble cellulose prior to modification is
approximately 300,000.
Another material of this type is sold under the trade name NATROSOL
PLUS CS Grade D-67 (RTM), by Aquafon Company, Wilmington, Delaware.
This material has a C16 substitution of from 0.50% to 0.95%, by weight. The
hydroxyethyl molar substitution for this material is from 2.3 to 3.7. The
average
molecular weight for the water soluble cellulose prior to modification is
approximately 700,000.
Preferred for use herein are C14 - C1g alkyl and alkenyl modified
hydroxy ethyl cellulose polymers having a degree of ethoxylation of from about
1.8 to about 3.2, preferably from about 2.0 to about 3.0, more preferably from
about 2.2 to about 2.8 and an alkyl and alkenyl substitution level of from
about
0.3 to about 0.8, preferably from about 0.4 to about 0.6. Highly preferred are
cetyi modified hydroxy ethyl cellulose polymers as available from the Aqualon
Co. under the trade names Polysurf 67 (RTM).
The hydrophobically modified cellulose ether is preferably present at a
level of from about 0.02% to about 5%, more preferably from about 0.05% to
about 1 %, and especially from about 0.1 % to about 0.5% by weight.
The modified cellulose ethers herein are particularly valuable for
providing excellent stability characteristics over normal temperatures as well
as
delivering shear thinning behaviour in a high surfactant matrix and for
delivery
of improved rheoiogical behaviour in combination with the selected cationic
polymeric skin conditioning agents.
The compositions according to the present invention are shear thinning
and preferably display a shear stress of about 150Pa at a shear rate in the
range of from about 100s-1 to about 600s-1 at 25°C. Highly preferred
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compositions display a shear stress of about 150Pa at a shear rate in the
range
from about 400s-1 to about 600s-1 at 25°C (as measured using a Carri-
Med
CSL 100 Rheometer with a spindle of cone 4cm and 2 degrees 49 micron
truncation).
Neutralizing agents suitable for use in neutralizing acidic group containing
Theology modifying agents described herein include sodium hydroxide,
potasssium hydroxide, ammonium hydroxide, monoethanoiamine,
diethanolamine and triethanolamine and mixtures thereof.
The compositions according to the present invention also preferably
include a skin conditioning cationic polymer. The cationic polymer is valuable
in
the compositions according to the present invention for provision of skin feel
attributes and for improved Theology and application characteristics in the
presence of the hydrophobically modified cellulose ether moiety. The polymeric
skin conditioning agent is preferably present at a level from about 0.01 % to
about 5%, preferably from about 0.05% to about 3% and_ especially from about
0.1 % to about 2% by weight.
Suitable polymers are high molecular weight materials (mass-average
molecular weight determined, for instance, by light scattering, being
generally
from about 2,000 to about 5,000,000, preferably from about 5,000 to about
3,000,000 more preferably from 100,000 to about 1,000,000).
Representative classes of polymers include cationic polysaccharides;
cationic homopolymers and copolymers derived from acrylic and/or methacrylic
acid; cationic cellulose resins; cationic copolymers of
dimethyldiallylammonium
chloride and acrylamide and or acrylic acid; cationic homopolymers of
dimethyldiallylammonium chloride; cationic pofyalkylene and
ethoxypolyalkylene imines; quaternized silicones, and mixtures thereof.
By way of exemplification, cationic polymers suitable for use herein
include cationic guar gums such as hydroxypropyl trimethyl ammonium guar
gum (d.s. of from 0.11 to 0.22) available commercially under the trade names
Jaguar C-14-S(RTM) and Jaguar C-17(RTM) and also Jaguar C-16(RTM),
which contains hydroxypropyl substituents (d.s. of from 0.8-1.1) in addition
to
the above-specified cationic groups, and quaternized cellulose ethers
available
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commercially under the trade names Ucare Polymer JR-30M, JR-400, Catanal
_, (RTM) and Celquat. Other suitable cationic polymers are homopolymers of
dimethyldiallylammonium chloride available commercially under the trade name
Merquat 100, copolymers of dimethyl aminoethylmethacrylate and acryiamide,
copolymers of dimethyldiallyiammonium chloride and acrylamide, available
commercially under the trade names Merquat 550 and Merquat S, acrylic
acid/dimethyldiallylammonium chloridelacrylamide copolymers available under
the trade name Merquat 3300, quaternized vinyl pyrrolidone acrylate or
methacrylate copolymers of amino alcohol available commercially under the
trade name Gafquat, for example Polyquaternium 11, 23 and 28 (quaternized
copolymers of vinyl pyrrolidone and dimethyl aminoethylmethacrylate - Gafquat
755N and HS-100), vinyl pyrrolidone/vinyf imidazoiium methochloride
copolymers available under the trade names Luviquat HM552, Pofyquaternium
2, and polyalkyleneimines such as polyethylenimine and ethoxylated
polyethylenimine.
The present compositions can also comprise a nonionic or anionic
polymeric thickening component, especially a water-soluble polymeric
materials, having a molecular weight greater than about 20,000. By "water-
soluble polymer" is meant that the material will form a substantially clear
solution in water at a 1 % concentration at 25°C and the material will
increase
the viscosity of the water. Examples of water-soluble polymers which may
desirably be used as an additional thickening component in the present
compositions, are hydroxyethylcellulose, hydroxypropyl cellulose,
hydroxypropyi methyiceiiuiose, polyethylene glycol, polyacrylamide,
polyacrylic
acid, polyvinyl alcohol, polyvinyl pyrrolidone K-120, dextrans, for example
Dextran purified crude Grade 2P, available from D8~0 Chemicals,
carboxymethyl cellulose, plant exudates such as acacia, ghatti, and
tragacanth,
seaweed extracts such as sodium alginate, propylene glycol alginate and
sodium carrageenan. Preferred as the additional thickeners for the present
compositions are natural polysaccharide materials. Examples of such materials
are guar gum, locust bean gum, and xanthan gum. Also suitable herein
preferred is hydroxyethyl cellulose having a molecular weight of about
700,000.
Additional polymeric thickening agents include acrylic acid/ethyl acrylate
copolymers and the carboxyvinyl polymers sold by the B.F. Goodrich Company
under the trade mark of Carbopol resins. These resins consist essentially of a
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colloidally water-soluble polyalkenyl polyether crosslinked polymer of acrylic
acid crosslinked with from 0.75% to 2.00% of a crosslinking agent such as for
example polyallyl sucrose or polyallyl pentaecythritol. Examples include
Carbopol 934, Carbopol 940, Carbopol 950, Carbopol 980, Carbopol 951 and
Carbopol 981. Carbopol 934 is a water-soluble polymer of acrylic acid
crosslinked with about 1 % of a polyallyl ether of sucrose having an average
of
about 5.8 allyl groups for each sucrose molecule. Also suitable for use herein
are hydrophobically-modified cross-linked polymers of acrylic acid having
amphipathic properties available under the Trade Name Carbopol 1382,
Carbopol 1342 and Pemulen TR-1 (CFTA Designation: Acrylates/10-30 Alkyl
Acryfate Crosspolymer). A combination of the polyalkenyl polyether cross-
linked acrylic acid polymer and hydrophobically modified cross-linked acrylic
acid polymer is also suitable for use herein.
The polymeric thickening component, if present in the compositions of the
present invention, is at a level of from 0.3% to 5.0%, preferably from 0.4% to
3.0% by weight.
Further additional thickening agents suitable for use herein include
ethylene glycol or polyethylene glycol esters of a fatty acid having from
about
16 to about 22 carbon atoms and up to 7 ethyleneoxy units, preferably the
ethylene glycol stearates, both mono and distearate, but particularly the
distearate containing less than about 7% of the mono stearate, alkanolamides
of fatty acids, having from about 16 to about 22 carbon atoms, preferably
about
16 to 18 carbon atoms such as stearic monoethanolamide, stearic
diethanolamide, stearic monoisopropanolamide and stearic monoethanolamide,
alkyl (C16 - C22) dimethyl amine oxides such as stearyl dimethyl amine oxide
and electrolytes such as magnesium sulphate and sodium chloride salts .
A preferred feature of the compositions of the present invention is a
solubilising agent for the hydrophobically modified cellulose ether. The
solubifising agent is valuable for limiting aggregation of cellulose ether
possibly .
via interaction around the hydrophobic pendant chains on the polymeric
moieties. The solubilising agent is preferably present at a level of from
about
0.1 % to about 10%, more preferably from about 0.5% to about 5%, and
especially from about 1 % to about 4% by weight. The ratio of hydrophobically
CA 02206339 1997-OS-28
WO 96117916 PCT/US95/15722
modified cellulose ether to solubilising agent is in the range of from about
0.1
to about 0.2 : 5, preferably from about 0.3 : 5 to about 0.4 : 1.
Suitable solubilising agents include water-soluble polyofs. Preferred are
water soluble polyols having molecular weights of from about 40 to about 2000,
more preferably from about 50 to about 500 and especially from about 58 to
about 200 and multiple hydroxyl groups. Multiple hydroxyl groups as defined
herein means from about 2 to about 6 hydroxyl groups. Water-soluble polyols
suitable for inclusion herein as solubilising agents are selected from
glycerin,
propylene glycol, hexylene glycol, mannitol, polyethylene glycol, sorbitol,
polyethylene glycol and propylene glycol ethers of methyl glucose (e.g. ethyl
gfucam E-20 and propylglucam P-10), polyethylene glycol and propylene glycol
ethers of lanolin alcohol (e.g. Solulan-75) and mixtures thereof. Highly
preferred solubilising agents for use herein are glycerin and propylene
glycol.
Mild surfactants suitable for inclusion in compositions according to the
present invention can be selected from anionic, nonionic, amphoteric and
zwitterionic surfactants and mixtures thereof. The total level of surfactant
is
preferably from about 5% to about 60%, more preferably from about 6% to
about 40%, and especially from about 8% to about 35% by weight. The
compositions preferably comprise a mixture of anionic with zwitterionic and/or
amphoteric surfactants. The level of the individual anionic, zwitterionic and
amphoteric surfactant components, where present, is in the range from about
1 % to about 15%, and especially from about 2% to about 13% by weight of the
composition, while the level of nonionic surfactant, where present, is in the
range from about 0.1 % to about 20% by weight, preferably from about 0.5% to
about 16%, more preferably from about 1 % to about 12% by weight. The
weight ratio of anionic surfactant: zwitterionic and/or amphoteric surfactant
is in
the range from about 1:2 to about 6:1. Other suitable compositions within the
scope of the invention comprise mixtures of anionic, zwitterionic and/or
amphoteric surfactants with one or more nonionic surfactants. Preferred for
use herein are soluble or dispersible nonionic surfactants selected from
ethoxylated animal and vegetable oils and fats and mixtures thereof,
sometimes referred to herein as "oi!-derived" nonionic surfactants.
Anionic surfactants suitable for inclusion in the compositions of the
invention can generally be described as mild synthetic detergent surfactants
and include ethoxylated alkyl sulfates, alkyl glyceryl ether sulfonates,
methyl
CA 02206339 2000-09-06
12
acyi taurates, fatty aryl glycinates, N-acyl glutamates, acyi isethionates,
alkyl
suifosuccinates, alpha-sulfonated fatty acids, their salts andlor their
esters, alkyl
ethoxy carboxylates, alkyl phosphate esters, ethoxylated alkyl phosphate
esters, acyl sarcosinates and fatty acidlprotein condensates, and mixtures
thereof. Alkyl andlor aryl chain lengths for these surfactants are Cg-C22
preferably C1p-C1g snore preferably C12_C'4.
Preferred for use herein from the viewpoint of optunum mildness and
lathering characteristics are the salts of sulfuric acid esters of the
reaction
product of 1 mole of a higher fatty alcohol and from about 1 to about 12 moles
of ethylene oxide, with sodium and magnesium being the preferred counterions.
Particularly preferred are the alkyl sulfates containing from about 2 to 6,
preferably 2 to 4 moles of ethylene oxide, such as sodium iaureth-2 sulfate,
sodium laureth-3 sulfate and magnesium sodium laureth-3.8 sulfate. In
preferred embodiments, the anionic surfactant contains at least about 509,
especially at least about 75% by weight of ethoxylated alkyl sulfate.
The compositions for use herein suitably also contain an amphoteric
surfactant. Amphoteric surfactants suitable for use in the compositions of the
invention include:
(a) imidazolinium surfactants of formula (I)
CZH40R2
R N~CH2Z
1~~
.SIN
wherein R1 is C7-C22 alkyl or aikenyl, R2 is hydrogen or CH2Z,
each e' is independently C02M or CH2C02M, and M is H, alkali
metal, alkaline earth metal, ammonium or alkanolammonium;
and/or ammonium derivatives of formula (ll)
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13
CZH40H
R1CONH(CH2)~N+CHZZ
RZ
wherein R1, R2 and Z are as defined above;
(b) aminoalkanoates of formula (III)
R~ NH(CH2)nC02M
iminodialkanoates of formula (11n
R1 N[(CH2)mCO2Ml2
and iminopofyalkanoates of formula (V~
R~~N(CH2)pj,4N[CH2C02M]a
CH2C02M
wherein n, m, p, and q are numbers from 1 to 4, and R1 and M
are independently selected from the groups specified above; and
(c) mixtures thereof.
Suitable amphoteric surfactants of type (a) are marketed under the trade
name Miranot and Empigen and are understood to comprise a complex mixture
of species. Traditionally, the Miranols have been described as having the
general formula 1, although the CTFA Cosmetic Ingredient Dic~iohary, 3rd
Edition indicates the non-cyclic structure II while the 4th Edition indicates
yet
another structural isomer in which R2 is O-linked rather than N-linked. In
practice, a complex mixture of cyclic and non-~ydic species is likely to exist
and
both definitions are given here for sake of completeness. Preferred for use
herein, however, are the non-cyclic species.
Examples of suitable amphoter'~c surfactants of type (a) include
compounds of formula I andlor Il in which R~ is CgH~~ (especially iso-capryl),
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CgH ~ g and C~ ~ H23 alkyl. Especially preferred are the compounds in which R~
is CgH~g, Z is CO2M and R2 is H; the compounds in which R~ is C~~H23, Z is
C02M and R2 is CH2C02M; and the compounds in which R~ is C~ ~ H23, Z is
C02M and R2 is H.
In CTFA nomenclature, materials suitable for use in the present
invention include cocoamphocarboxypropionate, cocoamphocarboxy propionic
acid, and especially cocoamphoacetate and cocoamphodiacetate (otherwise
referred to as cocoamphocarboxyglycinate). Specific commercial products
include those sold under the trade names of Ampholak 7TX (sodium carboxy
methyl tallow polypropyl amine), Empigen CDL60 and CDR 60 (Albright &
Wilson), Miranol H2M Conc. Miranol C2M Conc. N.P., Miranol C2M Conc. O.P.,
Miranol C2M SF, Miranol CM Special (Rhone-Poulenc); Alkateric 2CIB (Alkaril
Chemicals); Amphoterge W-2 (Lonza, Inc.); Monateric CDX-38, Monateric
CSH-32 (Mona Industries); Rewoteric AM-2C (Rewo Chemical Group); and
Schercotic MS-2 (Scher Chemicals).
It will be understood that a number of commercially-available amphoteric
surfactants of this type are manufactured and sold in the form of
electroneutral
complexes with, for example, hydroxide counterions or with anionic sulfate or
sulfonate surfactants, especially those of the sulfated Cg-C~ g alcohol, Cg-C~
g
ethoxylated alcohol or Cg-C~ g acyl giyceride types. Preferred from the
viewpoint of mildness and product stability, however, are compositions which
are essentially free of (non-ethoxylated) sulfated alcohol surfactants. Note
also
that the concentrations and weight ratios of the amphoteric surfactants are
based herein on the uncomplexed forms of the surfactants, any anionic
surfactant counterions being considered as part of the overall anionic
surfactant
component content.
Examples of preferred amphoteric surfactants of type (b) include N-alkyl
polytrimethylene poly-, carboxymefhylamines sold under the trade names
Ampholak X07 and Ampholak 7CX by Berol Nobel and also salts, especially the
triethanolammonium salts and salts of N-iauryl-beta-amino propionic acid and
N-lauryl-imino-dipropionic acid. Such materials are sold under the trade name
Deriphat by Henkel and Mirataine by Rhone-Poulenc.
CA 02206339 2000-09-06
The compositions herein can also contain from about 0.1 % to about
20%, more preferably from about 0.1 % to about 1096, and especially from
about 1 % to about 8% of a iwitterionic surfactant.
Betaine surfactants suitable for inclusion in cleansing compositions
include alkyl betaines of the formula R5RgR7N+ (CH2)nC02M(VI) and amido
betaines of the formula (Vll)
R6
!
RSCON ( CHZ ) m i ( CH2 ) nC02M
R?
wherein R5 is C12-(~22 alkyl or alkenyl, R,6 and R7 are independently C1-Cg
alkyl, M is H, alkali metal, alkaline earth metal, ammonium or
alkanolammonium, and n, m are each numbers from 1 to 4. Preferred betaines
include cocoamidopropyldimethy~arboxymethyl betaine,
laurylamidopropyldimethylcarboxymethyl betaine and Tego betaine.
The compositions of the invention preferably also contain from about
0.1 °~ to about 20%, preferably from about 1 % to about 15%, and more
preferably from about 2°~6 to about 10% by weight of an oil derived
nonionic
surfactant or mi~ctur~e of oil derived nonionic surfactants. Oil derived
nonionic
surfactants are valuable in composit'rons according to the invention for the
provision of skin feel benefits both in use and after use. Suitable oil
derived
nonionic surfactants for use herein include water soluble vegetable and animal-
derived emollients such as triglycerides with a polyethyleneglycol chain
inserted; ethoxylated mono and di-glycerides, polyethoxylated tanolins and
ethoxylated butter derivatives. One preferred class of oil-derived nonionic
surfactants for use herein have the general formula (VIII)
0
!!
RCOCH2CH(OH)CH~(OCH~CH2)nOH
wherein n is from about 5 to about 200, preferably from about 20 to about 100,
more preferably from about 30 to about 85, and wherein R comprises an
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aliphatic radical having on average from about 5 to 20 carbon atoms,
preferably
from about 7 to 18 carbon atoms.
Suitable ethoxylated oils and fats of this class include polyethyleneglycol
derivatives of glyceryl cocoate, glyceryl caproate, glyceryl caprylate,
glyceryl
tallowate, glyceryl palmate, glyceryl stearate, glyceryl laurate, glyceryl
oleate,
glyceryl ricinoleate, and glyceryl fatty esters derived from triglycerides,
such as
palm oil, almond oil, and corn oil, preferably gfyceryl tallowate and glyceryl
cocoate.
Suitable oil derived nonionic surfactants of this class are available from
Croda Inc. (New York, USA) under their Crovol line of materials such as Crovol
EP40 (PEG 20 evening primrose glyceride), Crovol EP 70 (PEG 60 evening
primrose glyceride) Crovol A-40 (PEG 20 almond glyceride), Crovol A-70 (PEG
60 almond glyceride), Crovol M-40 (PEG 20 maize glyceride), Crovol M-70
(PEG 60 maize glyceride), Crovol PK-40 (PEG 12 palm kernel glyceride), and
Crovol PK-70 (PEG 45 palm kernel glyceride) and under their Solan range of
materials such as Solan E, E50 and X polyethoxylated lanolins and Aqualose L-
20 (PEG 24 lanolin alcohol) and Aqualose W15 (PEG 15 lanolin alcohol)
available from Westbrook Lanolin. Further suitable surfactants of this class
are
commercially available from Sherex Chemical Co. (Dublin, Ohio, USA) under
their Varonic Li line of surfactants. These include, for example, Varonic LI
48
(polyethylene glycol (n=80) glyceryl tallowate, alternatively referred to as
PEG
80 glyceryl tallowate), Varonic LI 2 (PEG 28 gfyceryl tallowate), Varonic LI
420
(PEG 200 giyceryl tallowate), and Varonic LI 63 and 67 (PEG 30 and PEG 80
glyceryl cocoates). Other oil-derived emollients suitable for use are PEG
derivatives of corn, avocado, and babassu oil, as well as Softigen 767 (PEG(6)
capryliclcapric glycerides).
Also suitable for use herein are nonionic surfactants derived from
composite vegetable fats extracted from the fruit of the Shea Tree '
(Butyrospermum Karkii Kotschy) and derivatives thereof. This vegetable fat,
known as Shea Butter is widely used in Central Africa for a variety of means
such as soap making and as a barrier cream, it is marketed by Sederma (78610
Le Perray En Yvelines,, France). Particularly suitable are ethoxylated
derivatives of Shea butter available from Karlshamn Chemical Co. (Columbos,
Ohio, USA) under their Lipex range of chemicals, such as Lipex 102 E-75 and
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_ 17
Lipex 102 E-3 (ethoxylated mono, di-glycerides of Shea butter). Similarly,
ethoxylated derivatives of Mango, Cocoa and Illipe butter may be used in
compositions according to the invention. Although these are classified as
ethoxylated nonionic surfactants it is understood that a certain proportion
may
remain as non-ethoxylated vegetable oil or fat.
Other suitable oil-derived nonionic surfactants include ethoxylated
derivatives of almond oil, peanut oil, rice bran oil, wheat germ oil, linseed
oil,
jojoba oil, oil of apricot pits, walnuts, palm nuts, pistachio nuts, sesame
seeds,
rapeseed, cade oil, corn oil, peach pit oil, poppyseed oil, pine oil, castor
oil,
soybean oil, avocado oil, safflower oil, coconut oil, hazlenut oil, olive oil,
grapeseed oil, and sunflower seed oil.
Oil derived nonionic surfactants highly preferred for use herein from the
viewpoint of optimum mildness and skin feel characteristics are Lipex 102-3
(RTM) (PEG-3 ethoxylated derivatives of Shea Butter) and Softigen 767 (RTM)
(PEG-fi capryliclcapric glycerides).
In addition to the above oil derived nonionic surfactants, the
compositions of the invention can also comprise an auxiliary nonionic
surfactant
at levels from about 0.1 % to about 20%, more preferably from about 0.1 % to
about 10%, and. especially from about 1 % to about 8% by weight. Surfactants
of this class include C12-C14 fatty acid mono-and diethanolamides, sucrose
polyester surfactants and polyhydroxy fatty acid amide surfactants having the
general formula (IX).
0 R9
n
R8-C-N-Z2
a
The preferred N-alkyl, N-alkoxy or N-aryloxy, polyhydroxy fatty acid
amide surfactants according to formula (IX) are those in which Rg is C6-C31
hydrocarbyl, preferably Cg-C17 hydrocarbyl, including straight-chain and
branched chain alkyl and alkenyl, or mixtures thereof and Rg is typically C1-
Cg
alkyl or hydroxyalkyl, preferably methyl, or a group of formula -R1-O-R2
wherein R1 is C2-Cg hydrocarbyl including straight-chain, branched-chain and
cyclic (including aryl), and is preferably C2-C4 alkylene, R2 is C1-Cg
straight-
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_ 18
chain, branched-chain and cyclic hydrocarbyl including aryl and
oxyhydrocarbyl,
and is preferably C1-C4 alkyl, especially methyl, or phenyl. ZZ is a
polyhydroxyhydrocarbyl moiety having a linear hydrocarbyl chain with at least
2
(in the case of glyceraldehyde) or at least 3 hydroxyls (in the case of other
reducing sugars) directly connected to the chain, or an alkoxylated derivative
(preferably ethoxylated or propoxylated) thereof. Z2 preferably will be
derived
from a reducing sugar in a reductive amination reaction, most preferably Z2 is
a
glycityl moiety. Suitable reducing sugars include glucose, fructose, maltose,
lactose, galactose, mannose, and xylose, as well as glyceraldehyde. As raw
materials, high dextrose corn syrup, high fructose com syrup, and high maltose
corn syrup can be utilized as well as the individual sugars listed above.
These
corn syrups may yield a mix of sugar components for Z2. It should be
understood that it is by no means intended to exclude other suitable raw
materials. Z2 preferably will be selected from the group consisting of -CH2-
(CHOH)n-CH20H, -CH(CH20H)-(CHOH)n_1-CH2H,
CH2(CHOH)2(CHOR')CHOH)-CHZOH, where n is an integer from 1 to 5,
inclusive, and R' is H or a cyclic mono- or poly-saccharide, and alkoxylated
derivatives thereof. As noted, most preferred are glycityls wherein n is 4,
particularly -CH2-(CHOH)4-CH20H.
The most preferred polyhydroxy fatty acid amide has the formula
Rg(CO)N(CH3)CH2(CHOH)4CH20H wherein Rg is a C7-C17 straight chain
alkyl or alkenyl group.
In compounds of the above formula, Rg-CO-N< can be, for example,
cocoamide, stearamide, oleamide, lauramide, myristamide, capricamide,
palmiamide, tallowamide, etc.
A preferred process for making the above compounds having formula
(IX) comprises reacting a fatty acid triglyceride with an N-substituted
polyhydroxy amine in the substantial absence of lower (C1-C4) alcoholic
solvent, but preferably with an alkoxylated alcohol or alkoxylated alkyl
phenol -
such as NEODOL and using an alkoxide catalyst at temperatures of from about
50°C to about 140°C to provide high yields (90-98%) of the
desired products.
The compositions of the invention may also include an insoluble perfume
or cosmetic oil or wax or a mixture thereof at a level up to about 10%,
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_ 19 _
preferably up to about 3% by weight wherein the oil or wax is insoluble in the
sense of being insoluble in the product matrix at a temperature of
25°C.
Addition of such oils or waxes can provide emolliency, mildness and
rinsibility
characteristics to personal cleansing compositions according to the invention.
It
is a feature of the invention, however, that compositions having excellent
emolliency and mildness together with desirable physical attributes (clarity
etc.)
can be delivered which are essentially oil-free, ie which contain less than
about
1 %, preferably less than 0.5% by weight of an added oil phase. Physically,
preferred compositions of this type take the form of an optically-clear
solution or
microemulsion. In compositions including an additional perfume or cosmetic oil
or wax, preferably the weight ratio of oil-derived nonionic surfactant to
added oil
is at least about 1:2, more especially at least about 3:1.
Suitable insoluble cosmetic oils and waxes for use herein can be
selected from water-insoluble silicones inclusive of non-volatile polyalkyl
and
polyaryl siloxane gums and fluids, volatile cyclic and linear
polyalkylsiloxanes,
polyalkoxylated silicones, amino and quaternary ammonium modified silicones,
rigid cross-linked and reinforced silicones and mixtures thereof, C1-C24
esters
of Cg-C30 fatty acids such as isopropyl myristate, myristyl myristate and
cetyl
ricinoleate, Cg-C30 esters of benzoic acid, beeswax, saturated and unsaturated
fatty alcohols such as behenyl alcohol, hydrocarbons such as mineral oils,
petrolatum squalane and squalene, polybutene, fatty sorbitan esters (see US-
A-3988255, Seiden, issued October 26th 1976), lanolin and oil-like lanolin
derivatives, animal and vegetable triglycerides such as almond oil, peanut
oil,
wheat germ oil, rice bran oil, linseed oil, jojoba oil, oil of apricot pits,
walnuts,
palm nuts, pistachio nuts, sesame seeds, rapeseed, cade oil, corn oil, peach
pit
oil, poppyseed oil, pine oil, castor oil, soybean oil, avocado oil, safflower
oil,
coconut oil, hazlenut oil, olive oil, grapeseed oil, and sunflower seed oil,
and
C1-C24 esters of dimer and trimer acids such as diisopropyl dimerate,
diisostearylmalate, diisostearyldimerate and triisostearyltrimerate.
The viscosity of the final composition (Brookfield RVT DCP, 1 rpm with
Cone CP41 or CP52, 25°C, neat) is preferably at least about 500 cps,
more
preferably from about 1,000 to about 50,000 cps, especially from about 4,000
to
about 30,000 cps, more especially from about 4,000 to about 15,000 cps.
The cleansing compositions can optionally include other hair or skin
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_ 2p _
moisturizers which are soluble in the cleansing composition matrix. The
preferred level of such moisturizers is from about 0.5% to about 20% by
weight.
In preferred embodiments, the moisturizer is selected from essential amino
acid
compounds found naturally occurring in the stratum corneum of the skin and
water-soluble nonpolyol nonocclusives and mixtures thereof.
Some examples of more preferred nonoccfusive moisturizers are
polybutene, squalane, sodium pyrrolidone carboxylic acid, lactic acid, L-
proline,
guanidine, pyrrolidone, hydrolyzed protein and other collagen-derived
proteins,
aloe vera gel, acetamide MEA and LMEA and mixtures thereof.
Compositions according to the present invention may also include an
opacifier or pearlescing agent. Such materials may be included at a level of
from about 0.01 % to about 5%, preferably from about 0.2% to about 1.3% by
weight. A suitable opacifier for inclusion in the present compositions is a
polystyrene dispersion available under the trade names Lytron 621 & 631
(RTM) from Morton International. _
Additional opacifiers/pearlescers suitable for inclusion in the
compositions of the present invention include: titanium dioxide, Ti02;
EUERLAN 810 (RTM); TEGO-PEARL (RTM); Tong chain (C16 - C22) acyl
derivatives such as glycol or polyethylene glycol esters of fatty acid having
from
about 16 to about 22 carbon atoms and up to 7 ethyfeneoxy units;
alkanofamides of fatty acids, having from about 16 to about 22 carbon atoms,
preferably about 16 to 18 carbon atoms such as stearic monoethanolamide,
stearic diethanolamide, stearic monoisopropanolamide and stearic
monoethanolamide and alkyl (C16 - C22) dimethyl amine oxides such as
stearyl dimethyl amine oxide.
In preferred compositions the opacifier/pearlescer is present in the form
of crystals. In highly preferred compositions the opacifier/pearlescer is a
particulate polystyrene dispersion having a particle size of from about 0.05
microns to about 0.45 microns, preferably from about 0.17 microns to about 0.3
microns such dispersions being preferred from the viewpoint of providing
optimum rheology and shear-thinning behaviour. Highly preferred is styrene
PVP copolymer and Lyton 631 (RTM).
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A number of additional optional materials can be added to the cleansing
compositions each at a level of from about 0.1 % to about 2% by weight. Such
materials include proteins and polypeptides and derivatives thereof; water-
soluble or solubilizable preservatives such as DMDM Hydantoin, Germall 115,
methyl, ethyl, propyl and butyl esters of hydroxybenzoic acid, EDTA, Euxyl
(RTM) K400, natural preservatives such as benzyl alcohol, potassium sorbate
and bisabalol; sodium benzoate and 2-phenoxyethanol; other moisturizing
agents such as hyaluronic acid,, chitin , and starch-grafted sodium
polyacrylates
such as Sanwet (RTM) IM-1000, IM-1500 and IM-2500 available from Celanese
Superabsorbent Materials, Portsmith, VA, USA and described in US-A-
4,076,663; solvents ; anti-bacterial agents such as Oxeco (phenoxy
isopropanol); low temperature phase modifiers such as ammonium ion sources
(e.g. NH4 CI); viscosity control agents such as magnesium sulfate and other
electrolytes; colouring agents; Ti02 and Ti02-coated mica; perfumes and
perfume solubilizers; and zeolites such as Valfour BV400 and derivatives
thereof and Ca2+/Mg2+ sequestrants such as polycarboxylates, amino
polycarboxylates, polyphosphonates, amino polyphosphonates etc. Water is
also present at a level preferably of from about 15% to about 94.98%,
preferably from about 40% to about 90%, more preferably at least about 65%
by weight of the compositions herein.
The pH of the compositions is preferably from about 4 to about 10, more
preferably from about 6 to about 9, especially from about 5 to about 6.
The invention is illustrated by the following non-limiting examples.
In the examples, all concentrations are on a 100% active basis and the
abbreviations have the following designation:
Amphoteric Cocoamphodiacetate
Anionic 1 Sodium laureth-3 sulfate
Anionic 2 Sodium lauroyl sarcosinate
Nonionic PEG-3 Shea butter
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Crovol Crovol EP 70 (PEG 60 evening primrose triglycerides)
GA Polyhydroxy fatty acid amide of formula IX in which Rg is
C11-C17 alkyl, Rg is methyl, and Z2 is ,
CH2(CHOH)4CH20H
HMHEC Cetyl modified hydroxyethylcellulose having a nonionic
substitution of from about 0.4 to about 0.6 and a degree of
ethoxylation of from about 2.2 to about 2.8 - Polysurf 67
(RTM).
Polymer 1 Polymer JR-30(RTM) - hydroxyethylcelluiose reacted with
epichlorohydrin and quaternized with trimethylamine, m.wt.
4 x 106
Polymer 2 Gafquat 755N
Preservative Phenoxyethanol/sodium benzoate/EDTA (4:2:1 )
Pearlescer ~Ethylenegfycoldistearate!emulsifier mixture
Opacifier Lytron 631 (RTM)
Oil Soyabean Oil
Softigen 767 PEG(6) caprylicJcapric glycerides
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- 23 -
Examples I to VI
The following are personal cleansing compositions in the form of shower gel or
bath foam products and which are representative of the present invention:
I II III IV V VI
Amphoteric 3.0 3.0 - 5.0 - 4.0
Anionic 1 6.0 6.0 13.0 10.0 6.0 4.0
Anionic 2 1.0 2.0 2.0 2.0 1.0 -
GA 3.0 - - 3.0 3.0 -
Oil - 4.0 - 6.0 4.0 -
Softigen 767 - 1.0 - 2.0 2.0 -
Nonionic - 0.4 - 1.0 - 0.3
Crovol - - 1.0 - - 3.0
HMHEC 0.3 0.4 0.5 0.1 0.3 0.35
Polymer 1 0.8 1.0 - . 0.2 ~ 0.8 -
Polymer 2 - - 0.5 - - 0.2
Glycerine 1.0 3.0 1.0 2.0 1.5 5.0
Pearlescer - - - 3.0 1.0 1.0
Opacifier 0.2 0.3 0.4 - - -
Preservative 0.5 0.5 0.5 1.0 1.0 1.0
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Perfume 1.0 1.0 1.0 1.0 1.0 1.0 .
Zinc Stearate - - 0.8 - - 1.0 ,
Water _~_______ _____ to 100 ______________~__
Compositions I to VI are prepared by firstly dispersing the water-soluble
or colloidaliy water-soluble polymeric rheology modifier in water at 25
°C either
in a Tri-blender (RTM) or by extended stirring prior to neutralisation with
NaOH
or alternative base mixture and hydration. In examples II, IV and VI the
mixture
can be heated to about 50°C to enhance dispersion efficiency. Next the
solubilisation agent is added with further stirring. The surfactants and other
skin care agents can then be added along with the remaining water-soluble, oil-
insoluble ingredients. In compositions which comprise water-insoluble
ingredients an oil phase B is formed from these oil-soluble ingredients which
is
then admixed with A at ambient temperature. The polymeric dispersion is then
added to the ambient temperature mix and finally the remaining water,
preservative, opacifier and perfume are added.
The products provide excellent in-use and efficacy benefits including
mildness, skin conditioning, skin moisturising, stability, rheology,
application
characterisitcs, cleansing, lathering and rinsibility.
