U.S. patent application number 11/400359 was filed with the patent office on 2006-12-07 for structured multi-phased personal care composition comprising branched anionic surfactants.
Invention is credited to Edward Dewey III Smith, Robert John Strife, Scott William Syfert, Julic Ann Wagner, Karl Shiqing Wei.
Application Number | 20060276357 11/400359 |
Document ID | / |
Family ID | 36686004 |
Filed Date | 2006-12-07 |
United States Patent
Application |
20060276357 |
Kind Code |
A1 |
Smith; Edward Dewey III ; et
al. |
December 7, 2006 |
Structured multi-phased personal care composition comprising
branched anionic surfactants
Abstract
A multi-phase personal care composition is described that
comprises a first visually distinct phase including a structured
surfactant component and a second visually distinct phase. The
structured surfactant component comprises at least one branched
anionic surfactant and from 0 to 10% by weight of the first
visually distinct phase, of sodium trideceth sulfate.
Inventors: |
Smith; Edward Dewey III;
(Mason, OH) ; Wei; Karl Shiqing; (Mason, OH)
; Syfert; Scott William; (Ft. Mitchell, KY) ;
Strife; Robert John; (Fairfield, OH) ; Wagner; Julic
Ann; (Cincinnati, OH) |
Correspondence
Address: |
THE PROCTER & GAMBLE COMPANY;INTELLECTUAL PROPERTY DIVISION
WINTON HILL BUSINESS CENTER - BOX 161
6110 CENTER HILL AVENUE
CINCINNATI
OH
45224
US
|
Family ID: |
36686004 |
Appl. No.: |
11/400359 |
Filed: |
April 7, 2006 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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60670785 |
Apr 13, 2005 |
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60680114 |
May 12, 2005 |
|
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60680149 |
May 12, 2005 |
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Current U.S.
Class: |
510/130 |
Current CPC
Class: |
A61K 8/06 20130101; A61K
8/11 20130101; A61Q 19/10 20130101; A61Q 5/02 20130101; A61K 8/03
20130101; A61K 2800/412 20130101; A61K 8/42 20130101 |
Class at
Publication: |
510/130 |
International
Class: |
A61K 8/00 20060101
A61K008/00 |
Claims
1. A multi-phase personal care composition comprising: a first
visually distinct phase comprising a structured surfactant
component; and a second visually distinct phase; wherein said
structured surfactant component comprises at least one branched
anionic surfactant and from 0 to 10%, by weight of said first
visually distinct phase, of sodium trideceth sulfate.
2. The multi-phase personal care composition of claim 1, wherein
said structured surfactant component comprises 0.1% to 10%, by
weight of said first visually distinct phase, of sodium trideceth
sulfate.
3. The multi-phase personal care composition of claim 1, wherein
said structured surfactant component comprises 9.5%, by weight of
said first visually distinct phase, of sodium trideceth
sulfate.
4. The multi-phase personal care composition of claim 1, wherein
said composition comprises from about 2% to about 23.5%, by weight
of said first visually distinct phase, of said structured
surfactant component.
5. The multi-phase personal care composition of claim 1, wherein
said composition comprises from about 3% to about 21%, by weight of
said first visually distinct phase, of said structured surfactant
component.
6. The multi-phase personal care composition of claim 1, wherein
said branched anionic surfactant is selected from the group
consisting of sodium trideceth sulfate, sodium tridecyl sulfate,
ammonium trideceth sulfate, ammonium tridecyl sulfate, monomethyl
branched sulfated derivatives of branched hydrocarbons, and
mixtures thereof.
7. The multi-phase personal care composition of claim 6, wherein
said branched anionic surfactant comprises monomethyl branched
sulfated derivatives of hydrocarbons.
8. The multi-phase personal care composition of claim 1, wherein
said first visually distinct phase provides a Yield Stress of
greater than about 1.5 Pascal.
9. The multi-phase personal care composition of claim 1, wherein
said composition further comprises a polymeric phase
structurant.
10. The multi-phase personal care composition of claim 9, wherein
said polymeric phase structurant is selected from the group
consisting of deflocculating polymers, naturally derived polymers,
synthetic polymers, crosslinked polymers, block polymers, block
copolymers, copolymers, hydrophilic polymers, nonionic polymers,
anionic polymers, hydrophobic polymers, hydrophobically modified
polymers, associative polymers, oligomers, and mixtures
thereof.
11. The multi-phase personal care composition of claim 9, wherein
said multi-phase personal care composition comprises from about
0.05% to about 10%, by weight of said first visually distinct
phase, of said polymeric phase structurant.
12. The multi-phase personal care composition of claim 1, wherein
said first visually distinct phase and said second visually
distinct phase form a pattern.
13. The multi-phase personal care composition of claim 12 wherein
the pattern is selected from the group consisting of striped,
geometric, marbled, and combinations thereof.
14. The multi-phase personal care composition of claim 12, wherein
said composition is packaged in a container such that said pattern
is visible.
15. The multi-phase personal care composition of claim 1, wherein
said first visually distinct phase further comprises: (i) at least
one electrolyte; (ii) at least one alkanolamide; and (iii) water;
wherein said first visually distinct phase is non-Newtonian shear
thinning; and wherein
16. The multi-phase personal care composition of claim 1, wherein
said first visually distinct phase comprises: (a) said structured
surfactant component further comprising: (i) at least one nonionic
surfactant having an HLB from about 3.4 to about 15.0; (ii) at
least one amphoteric surfactant; and (b) an electrolyte.
17. The multi-phase personal care composition of claim 1, wherein
said first visually distinct phase further comprises a liquid
crystalline phase inducing structurant.
18. The multi-phase personal care composition of claim 17, wherein
said liquid crystalline phase inducing structurant is selected from
the group consisting of fatty acids, fatty alcohols, fatty esters,
trihydroxystrearin, and mixtures thereof.
19. The structured, multi-phase personal cleansing composition of
claim 1, wherein said composition additionally comprises a benefit
component, wherein said benefit component is selected from the
group consisting of emollients, particles, beads, skin whitening
agents, fragrances, colorants, vitamins and derivatives thereof,
sunscreens, preservatives, anti-acne medicaments, antioxidants,
chelators, essential oils, skin sensates, antimicrobial, and
mixtures thereof.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional
application Ser. No. 60/670,785 filed on Apr. 13, 2005 and U.S.
Provisional application Ser. No. 60/680,114 filed on May 12, 2005
and U.S. Provisional application Ser. No. 60/680,149 filed on May
12, 2005.
FIELD OF THE INVENTION
[0002] The present invention relates to a structured multi-phase
personal care composition that comprises at least one branched
anionic surfactant and from 0% to 10%, by weight of the first
visually distinct phase, of sodium trideceth sulfate.
BACKGROUND OF THE INVENTION
[0003] Personal cleansing compositions that attempt to provide
skin-conditioning benefits are known. Desirable personal cleansing
compositions must meet a number of criteria. For example, in order
to be acceptable to consumers, a multi-phase personal cleansing
composition must exhibit good cleaning properties, must exhibit
good lathering characteristics, must be mild to the skin (not cause
drying or irritation) and preferably should even provide a
conditioning benefit to the skin.
[0004] Many personal cleansing compositions are aqueous systems
comprising emulsified conditioning oil or other similar materials
in combination with a lathering surfactant. Although these products
provide both conditioning and cleansing benefits, it is often
difficult to formulate a product that deposits sufficient amount of
skin conditioning agents on skin during use. In order to combat
emulsification of the skin conditioning agents by the cleansing
surfactant, large amounts of the skin conditioning agent are added
to the compositions. However, this introduces another problem
associated with these cleansing and conditioning products. Raising
the level of skin conditioning agent in order to achieve increased
deposition negatively affects the compositions speed of lather
generation, total lather volume, performance and stability.
[0005] Some surfactants used in personal cleansing compositions,
such as, sodium trideceth sulfate and similarly homologous
chemicals based on tridecanol, also may depress the speed of lather
production, although such compositions provide relatively mild
cleansing. It is believed that the high level of branching in
tridecanol-based surfactants and compositions that comprise them,
exhibits less flash lather as a result of their water solubility.
Moreover, sodium trideceth sulfate and similar homologues based on
tridecanol, are relatively costly materials, as such, the
compositions do not enjoy broad commercial use.
[0006] Accordingly, the need still remains for body wash
composition that provides cleansing with increased lather longevity
and improved lathering characteristics, and skin benefits such as
silky skin feel, improved soft skin feel, and improved smooth skin
feel. It is desirable to formulate compositions comprising lower
levels, or even no sodium trideceth sulfate, which have the same
beneficial properties as high sodium trideceth sulfate
compositions.
SUMMARY OF THE INVENTION
[0007] The present invention relates to a multi-phase personal care
composition that comprises a first visually distinct phase
comprising a structured surfactant component; and a second visually
distinct phase. The structured surfactant component comprises at
least one branched anionic surfactant and from 0% to 10%, by weight
of the first visually distinct phase, of sodium trideceth
sulfate.
[0008] The inventors believe that mixtures of branched and linear
anionic surfactants can provide good mildness, structure, and
higher flash lather volume than compositions that comprise sodium
trideceth sulfate, as the only anionic surfactant. Sufficient
mildness can be provided by the highly branched tridecanol-based
anionic surfactant complemented by high flash lather volume from
linear structured surfactant components. These properties can be
accomplished in the same composition by blending sodium trideceth
sulfate with surfactants having a higher proportion of linear
surfactants than sodium trideceth sulfate or by selecting
surfactant which naturally have less branching than sodium
trideceth sulfate. A preferred surfactant component comprises a
substantial level of mono-methyl branched surfactants leading to
structure and stability of structure.
DETAILED DESCRIPTION OF THE INVENTION
[0009] The term "ambient conditions" as used herein, refers to
surrounding conditions at one (1) atmosphere of pressure, 50%
relative humidity, and 25.degree. C.
[0010] By the term "multi-phase" as used herein, is meant that the
phases of the present compositions occupy separate but distinct
physical spaces inside the package in which they are stored, but
are in direct contact with one another (i.e., they are not
separated by a barrier and they are not emulsified or mixed to any
significant degree). In one preferred embodiment of the present
invention, the "multi-phase" personal care compositions comprise at
least two visually distinct phases which are present within the
container as a visually distinct pattern. The pattern results from
the combination of the "multi-phase" composition by a process
herein described. The "patterns" or "patterned" include but are not
limited to the following examples: striped, marbled, rectilinear,
interrupted striped, check, mottled, veined, clustered, speckled,
geometric, spotted, ribbons, helical, swirl, arrayed, variegated,
textured, grooved, ridged, waved, sinusoidal, spiral, twisted,
curved, cycle, streaks, striated, contoured, anisotropic, laced,
weave or woven, basket weave, spotted, and tessellated. Preferably
the pattern is selected from the group consisting of striped,
geometric, marbled, and combinations thereof.
[0011] In a preferred embodiment, the striped pattern may be
relatively uniform across the dimension of the package.
Alternatively, the striped pattern may be uneven, i.e. wavy, or may
be non-uniform in dimension. The striped pattern does not need to
necessarily extend across the entire dimension of the package. The
size of the stripes can be at least about 0.1 mm in width and 10 mm
in length, preferably at least about 1 mm in width and at least 20
mm in length as measured from the package exterior. The phases may
be various different colors, and/or include particles, glitter or
pearlescent agents in at least one of the phases in order to offset
its appearance from the other phase(s) present.
[0012] The term "multi-phase personal care composition" as used
herein, refers to compositions intended for topical application to
the skin or hair.
[0013] The term "visually distinct phase" as used herein, refers to
a region of the multi-phase personal care composition having one
average composition, as distinct from another region having a
different average composition, wherein the regions are visible to
the unaided naked eye. This would not preclude the distinct regions
from comprising two similar phases where one phase could comprise
pigments, dyes, particles, and various optional ingredients, hence
a region of a different average composition. A phase generally
occupies a space or spaces having dimensions larger than the
colloidal or sub-colloidal components it comprises. A phase may
also be constituted or re-constituted, collected, or separated into
a bulk phase in order to observe its properties, e.g., by
centrifugation, filtration or the like.
[0014] The term "stable" as used herein, unless otherwise
specified, refers to compositions that maintain at least two
"separate" phases when sitting in undisturbed physical contact at
ambient conditions for a period of at least about 180 days wherein
the distribution of the two phases in different locations in the
package does not significantly change over time. Compositions of
the present invention, preferably exhibit enhanced stability, in
that the first visually distinct phase has greater than 50%
Viscosity Retention measured according to the T-Bar method
disclosed herein.
[0015] The term "structured surfactant component" as used herein
means the total of all anionic, nonionic, amphoteric, zwitterionic
and cationic surfactants in a phase. When calculations are based on
the structured surfactant component, water and electrolyte are
excluded from the calculations involving the structured surfactant
component, since surfactants as manufactured typically are diluted
and neutralized.
[0016] The term "structured," as used herein means having a
rheology that confers stability on the multi-phase composition. The
degree of structure is determined by characteristics determined by
one or more of the following methods the Yield Stress Method, or
the Zero Shear Viscosity Method or by the Ultracentrifugation
Method, all in the Test Methods below. Accordingly, a surfactant
phase of the multiphase composition of the present invention is
considered "structured," if the surfactant phase has one or more of
the following properties described below according to the Yield
Stress Method, or the Zero Shear Viscosity Method or by the
Ultracentrifugation Method. A surfactant phase is considered to be
structured, if the phase has one or more of the following
characteristics: [0017] A. a Yield Stress of greater than about 0.1
Pascal (Pa), more preferably greater than about 0.5 Pa, even more
preferably greater than about 1.0 Pa, still more preferably greater
than about 2.0 Pa, still even more preferably greater than about 3
Pa, and even still even more preferably greater than about 5 Pa as
measured by the Yield Stress and Zero Shear Viscosity Method
described hereafter; or [0018] B. a Zero Shear Viscosity of at
least about 500 Pascal-seconds (Pa-s), preferably at least about
1,000 Pa-s, more preferably at least about 1,500 Pa-s, even more
preferably at least about 2,000 Pa-s; or [0019] C. a Structured
Domain Volume Ratio as measured by the Ultracentrifugation Method
described hereafter, of greater than about 40%, preferably at least
about 45%, more preferably at least about 50%, more preferably at
least about 55%, more preferably at least about 60%, more
preferably at least about 65%, more preferably at least about 70%,
more preferably at least about 75%, more preferably at least about
80%, even more preferably at least about 85%.
[0020] Product Form:
[0021] The multi-phase personal care composition of the present
invention is typically extrudable or dispensable from a package.
The multi-phase personal care compositions typically exhibit a
viscosity of from about 1,500 centipoise (cP) to about 1,000,000
cP, as measured by the Viscosity Method as described in copending
application Ser. No. 10/841174 filed on May 7, 2004 titled
"Multi-phase Personal Care Compositions."
[0022] When evaluating a structured multi-phase personal care
composition, by the methods described herein, preferably each
individual phase is evaluated prior to combining, unless otherwise
indicated in the individual methodology. However, if the phases are
combined, each phase can be separated by centrifugation,
ultracentrifugation, pipetting, filtering, washing, dilution,
concentration, or combination thereof, and then the separate
components or phases can be evaluated. Preferably, the separation
means is chosen so that the resulting separated components being
evaluated is not destroyed, but is representative of the component
as it exists in the structured multi-phase personal care
composition, i.e., its composition and distribution of components
therein is not substantially altered by the separation means.
Generally, multi-phase compositions comprise domains significantly
larger than colloidal dimensions so that separation of the phases
into the bulk is relatively easy to accomplish while retaining the
colloidal or microscopic distribution of components therein.
Preferably, the compositions of the present invention are rinse-off
formulations, by which is meant the product is applied topically to
the skin or hair and then subsequently (i.e., within minutes) the
skin or hair is rinsed with water, or otherwise wiped off using a
substrate or other suitable removal means with deposition of a
portion of the composition.
[0023] In a preferred embodiment of the present invention the
structured multi-phase personal care composition comprises at least
two visually distinct phases wherein a first phase is visually
distinct from a second phase. Preferably, the visually distinct
phases are packaged in physical contact with one another and are
stable. Preferably, the visually distinct phases form a
pattern.
Phases:
[0024] The multi-phase personal care compositions of the present
invention comprise at least two visually distinct phases, wherein
the composition can have a first phase, a second phase, a third
phase, a fourth phase, and so on. The ratio of a first phase to a
second phase is typically from about 1:99 to about 99:1, preferably
from 90:10 to about 10:90, more preferably from about 80:20 to
about 20:80, even more preferably about from 70:30 to about 30:70,
still even more preferably about 60:40 to about 40:60, even still
even more preferably about 50:50.
[0025] First Visually Distinct Phase:
[0026] The first visually distinct phase of a multi-phase personal
care composition of the present invention can comprises a
structured surfactant component. The structured surfactant
component comprises at least of branched anionic surfactant and
from 0 to 10% by weight of the first visually distinct phase, of
sodium trideceth sulfate. Preferably, the structured surfactant
component comprises a mixture of surfactants. The structured
multi-phased personal care composition comprises from about 1% to
about 99%, by weight of the composition, of said first visually
distinct phase.
[0027] Structured surfactant component:
[0028] The structured surfactant component comprises at least one
branched anionic surfactant. The structured surfactant component
preferably comprises a lathering surfactant or a mixture of
lathering surfactants. The structured surfactant component
comprises surfactants suitable for application to the skin or hair.
Suitable surfactants for use herein include any known or otherwise
effective cleansing surfactant suitable for application to the
skin, and which are otherwise compatible with the other essential
ingredients in the structured multi-phase personal care composition
including water. These surfactants include anionic, nonionic,
cationic, zwitterionic, amphoteric surfactants, soap, or
combinations thereof. Preferably, anionic surfactant comprises at
least 40% of the structured surfactant component, more preferably
from about 45% to about 95% of the structured surfactant component,
even more preferably from about 50% to about 90%, still more
preferably from about 55% to about 85%, and even still most
preferably at least about 60% of the structured surfactant
component comprises anionic surfactant.
[0029] The multi-phase personal care composition preferably
comprises a structured surfactant component at concentrations
ranging from about 2% to about 23.5%, more preferably from about 3%
to about 21%, even more preferably from about 4% to about 20.4%,
still more preferably from about 5% to about 20%, still even more
preferably from about 13% to about 18.5%, and even still even more
preferably from about 14% to about 18%, by weight of the first
visually distinct phase.
[0030] The first visually distinct phase comprising the structured
surfactant component is preferably a structured domain comprising
surfactants. The structured domain enables the incorporation of
high levels of benefit components in a separate phase that are not
emulsified in the composition. In a preferred embodiment the
structured domain is an opaque structured domain. The opaque
structured domain is preferably a lamellar phase. The lamellar
phase produces a lamellar gel network. The lamellar phase can
provide resistance to shear, adequate yield to suspend particles
and droplets and at the same time provides long term stability,
since it is thermodynamically stable. The lamellar phase tends to
have a higher viscosity thus minimizing the need for viscosity
modifiers.
[0031] The first visually distinct phase typically provides a Total
Lather Volume of at least about 600 ml, preferably greater than
about 800 ml, more preferably greater than about 1000 ml, even more
preferably greater than about 1200 ml, and still more preferably
greater than about 1500 ml, as measured by the Lather Volume Test
described hereafter. The first visually distinct phase preferably
has a Flash Lather Volume of at least about 300 ml, preferably
greater than about 400 ml, even more preferably greater than about
500 ml, as measured by the Lather Volume Test described
hereafter.
[0032] Suitable surfactants are described in McCutcheon's,
Detergents and Emulsifiers, North American edition (1986),
published by allured Publishing Corporation; and McCutcheon's,
Functional Materials, North American Edition (1992); and in U.S.
Pat. No. 3,929,678 issued to Laughlin, et al on Dec. 30, 1975.
[0033] Preferred linear anionic surfactants for use in the
structured surfactant phase of the multiphase, personal care
composition include ammonium lauryl sulfate, ammonium laureth
sulfate, sodium lauryl sulfate, sodium laureth sulfate, potassium
laureth sulfate, sodium lauryl sarcosinate, sodium lauroyl
sarcosinate, lauryl sarcosine, cocoyl sarcosine, ammonium cocoyl
sulfate, potassium lauryl sulfate, and combinations thereof.
[0034] Amphoteric surfactants are suitable for use in the
multiphase composition of the present invention. The amphoteric
surfactants include those that are broadly described as derivatives
of aliphatic secondary and tertiary amines in which the aliphatic
radical can be straight or branched chain and wherein one of the
aliphatic substituents contains from about 8 to about 18 carbon
atoms and one contains an anionic water solubilizing group, e.g.,
carboxy, sulfonate, sulfate, phosphate, or phosphonate. Examples of
compounds falling within this definition are sodium
3-dodecyl-aminopropionate, sodium 3-dodecylaminopropane sulfonate,
sodium lauryl sarcosinate, and N-alkyltaurines. Zwitterionic
surfactants suitable for use include those that are broadly
described as derivatives of aliphatic quaternary ammonium,
phosphonium, and sulfonium compounds, in which the aliphatic
radicals can be straight or branched chain, and wherein one of the
aliphatic substituents contains from about 8 to about 18 carbon
atoms and one contains an anionic group, e.g., carboxy, sulfonate,
sulfate, phosphate, or phosphonate. Zwitterionic surfactants
suitable for use in the multiphase, personal care composition
include betaines, including cocoamidopropyl betaine.
[0035] Non-limiting examples of preferred nonionic surfactants for
use herein are those selected form the group consisting of glucose
amides, alkyl polyglucosides, sucrose cocoate, sucrose laurate,
alkanolamides, ethoxylated alcohols and mixtures thereof. In a
preferred embodiment the nonionic surfactant is selected from the
group consisting of glyceryl monohydroxystearate, isosteareth-2,
trideceth-3, hydroxystearic acid, propylene glycol stearate, PEG-2
stearate, sorbitan monostearate, glyceryl laurate, laureth-2,
cocamide monoethanolamine, lauramide monoethanolamine, and mixtures
thereof.
[0036] Mixtures of anionic surfactants can be used in some
embodiments, including mixtures of linear and branched surfactants,
and anionic surfactants combined with nonionic, amphoteric, and/or
zwitterionic surfactants.
[0037] An electrolyte, if used, can be added per se to the
multiphase personal care composition or it can be formed in situ
via the counterions included in one of the raw materials. The
electrolyte preferably includes an anion comprising phosphate,
chloride, sulfate or citrate and a cation comprising sodium,
ammonium, potassium, magnesium or mixtures thereof. Some preferred
electrolytes are sodium chloride, ammonium chloride, sodium or
ammonium sulfate. The electrolyte is preferably added to the
structured surfactant phase of the composition in the amount of
from about 0.1% to about 15% by weight, preferably from about 1% to
about 6% by weight, more preferably from about 3% to about 6%, by
weight of the structured surfactant composition.
[0038] In one embodiment of the present invention, the multiphase,
personal care composition comprises a structured surfactant phase
comprising a mixture of at least one nonionic surfactant, and an
electrolyte. In another embodiment, the surfactant phase can
comprise a mixture of surfactants, water, at least one anionic
surfactant, an electrolyte, and at least one alkanolamide.
[0039] Branched Anionic Surfactants:
[0040] At least one anionic surfactant comprising anionic
surfactant molecules of the present invention is preferably
branched. A surfactant molecule is branched when the hydrocarbon
tail of the surfactant molecule comprises at least one ternary or
quaternary carbon atom, such that a methyl, ethyl, propyl, butyl,
pentyl or hexyl side chain extends from the hydrocarbon backbone.
The hydrocarbon backbone is described by the longest hydrocarbon
length in the hydrocarbon tail. A side chain in the branched
hydrocarbon of a surfactant molecule can be described by its
position on the backbone, counting from the first carbon attached
to a hydrophilic atom, enumerated as carbon number 1, the adjacent
carbon on the backbone being carbon number 2, and so on. Side
chains are also described by their length, a single carbon side
chain denoted methyl; a 2-carbon length denoted ethyl, and so on.
Side chains that have their own branching are denoted by
conventional nomenclature techniques, e.g., isopropyl, but are less
common. Anionic surfactant molecules which do not have branching
are linear anionic surfactant molecules, and surfactants comprising
a preponderance of linear anioinic surfactant molecules as
indicated hereafter are linear anionic surfactants. Most anionic
surfactants derived from common natural sources such as coconut and
palm, are linear anionic surfactants, such as ammonium lauryl
sulfate, sodium lauryl ether sulfate. Linear anionic surfactants
can also be derived from other sources including synthetic.
[0041] Because an anionic surfactant typically comprises a mixture
of different types of surfactant molecules, anionic surfactants can
be called linear or branched depending on the relative amounts of
individual surfactant molecules of different types that comprise
the anionic surfactant. For example, sodium tridecyl sulfate and
sodium trideceth sulfate can be called branched surfactants because
they typically comprise nearly all (>95%) branched surfactant
molecules. For the purposes of the present invention, an anionic
surfactant is considered branched surfactant when at least 10% of
its hydrocarbon chains are branched molecules.
[0042] Branched anionic surfactants comprise surfactant molecules
having different kinds of branching. Some branched anionic
surfactants, such as tridecanol based sulfates such as sodium
trideceth sulfate, comprise a high level of branching, with over
80% of surfactant molecules comprising at least 2 branches and
having an average of about 2.7 branches per molecule in some sodium
trideceth sulfates. Other branched anionic surfactants, such as
C.sub.12-13 alkyl sulfate derived from Safol .TM. 23 alcohol
(Sasol, Inc, Houston, Tex., USA) comprise a mixture of about 50-55%
linear anionic surfactant molecules, with about 15-30% branched
surfactant molecules. For the purposes of the present invention,
anionic surfactants comprising more than 10% branched surfactant
molecules, but having an average of less than 2.0 branches per
molecule, are considered monomethyl branched anionic
surfactants.
[0043] Branching information for many surfactants is typically
known or obtainable from suppliers of branched alcohol feedstocks.
For example, Sasol publishes the following information related to
Safol .TM. 23 primary alcohol: TABLE-US-00001 Linear Alcohol
Isomers 50% Mono-Methyl Alcohol Isomers 30% Other Primary Alcohol
Isomers <20% Total 100%
Safol .TM. 23 alcohol can be sulfated, for example in an
SO.sub.3/air stream falling film reactor followed by rapid
neutralization with sodium hydroxide to produce sodium C.sub.12-13
alkyl sulfate, a process known in the art. Since the sulfation
process involves no rearrangement of the hydrocarbon backbone, the
backbone of the C.sub.12-13 alkyl sulfate has the same structure as
the Safol .TM. 23 alcohol, and is a branched anionic surfactant,
and is also a monomethyl branched anionic surfactant. Other
suppliers of alcohols provide similar information on their primary
alcohols, e.g., Shell Chemical for the Neodol .TM. primary
alcohols. In the absence of published analytical information by
established methods from material suppliers on branching of a
surfactant or its feedstock alcohol, analytical techniques known to
those skilled in the art can be used to determine branching. For
example, when the structure of the hydrocarbon tail is not very
complex (i.e., less than about a dozen major components), a gas
chromatography-mass spectrometry (GC-MS) technique can be used,
involving oxidation of the alcohol in acetone (cosolvent) by a 3.3
M H.sub.2CRO.sub.4 Jones Reagent to a fatty acid followed by
oxazoline derivatization using 2-amino, 2-methyl, 1-propanol at 200
C for 2 hours, dilution with CHCl.sub.3 and subsequent washing with
distilled water, drying with sodium sulfate prior to injection into
a split injection (280 C) or on-column injection. A typical GC
program is 80-320 C at 5 C/min rate on a 30 m.times.0.25 mm DB-1
(0.25 uM film) column, and can give specific information on
branching location for a majority of a hydrocarbon tail of an
anionic surfactant. When co-elution of species and/or elution of
unknown components occur, GC-MS is able to obtain the amount of
branched components, which is taken as 100% minus the sum of n-C12
and n-C13 eluted. Typically, n-C.sub.11, n-C.sub.12 and n-C.sub.13
elution times are known for a column and/or can be obtained by
simple running of standards which are available. By convention for
our invention, inventors sum all oxazoline peaks in the GC window
between n-C.sub.11 and n-C.sub.12, said peaks are the branched
C.sub.12 peaks; sum all oxazoline peaks in the GC window between
n-C.sub.12 and n-C.sub.13, said peaks are the branched C.sub.13
peaks; dividing the peak areas obtained by the total area obtained,
including linear C.sub.12 and linear C.sub.13, to obtain the
fractional amount of each component. By our convention, the sum of
the peak fractions in the branched C.sub.12 and branched C.sub.13
windows, added together, is the fraction of branched molecules,
which can be expressed as a percentage. The integrated area under
each GC peak is the peak information used in the calculations. If
necessary, the surfactant can even be obtained by extraction from a
composition first, e.g. by filtration such as cross flow
filtration. From the GC data, the number of branch points per
hydrocarbon chain is summed, multiplying number of branches per
molecule by mole fraction for each species identified to obtain an
average degree of branching per molecule for the surfactant. For
example, 50% of molecules having 1 branch point with 50% linear
molecules is an average degree of branching of 0.5. For highly
branched molecules (>1.25 average degree of branching), such as
sodium trideceth sulfate, determining degree of branching from the
GC spectra can be difficult and require specialized equipment, so
instead is determined from conventional NMR techniques, using the
ratio of ternary to secondary carbon-carbon bonds in the
hydrocarbon tail to determine average degree of branching.
[0044] Branched anionic surfactants include but are not limited to
the following surfactants: sodium trideceth sulfate, sodium
tridecyl sulfate, sodium C.sub.12-13 alkyl sulfate, sodium
C.sub.12-15 alkyl sulfate, sodium C.sub.11-15 alkyl sulfate, sodium
C.sub.12-18 alkyl sulfate, sodium C.sub.10-16 alkyl sulfate, sodium
C.sub.12-13 pareth sulfate, sodium C.sub.12-13 pareth-n sulfate,
and sodium C.sub.12-14 pareth-n sulfate. Other salts of all the
aforementioned surfactants are useful, such as TEA, DEA, ammonia,
potassium salts. Useful alkoxylates include the ethylene oxide,
propylene oxide and EO/PO mixed alkoxylates. Phosphates,
carboxylates and sulfonates prepared from branched alcohols are
also useful anionic branched surfactants. Branched surfactants can
be derived from synthetic alcohols such as the primary alcohols
from the liquid hydrocarbons produced by Fischer-Tropsch condensed
syngas, for example Safol .TM. 23 Alcohol available from Sasol
North America, Houston, Tex.; from synthetic alcohols such as
Neodol .TM. 23 Alcohol available from Shell Chemicals, USA; from
synthetically made alcohols such as those described in U.S. Pat.
No. 6,335,312 issued to Coffindaffer, et al on Jan. 1, 2002.
Preferred alcohols are Safol .TM. 23 and Neodol .TM. 23. Preferred
alkoxylated alcohols are Safol .TM. 23-3 and Neodol .TM. 23-3.
Sulfates can be prepared by conventional processes to high purity
from a sulfur based SO.sub.3 air stream process, chlorosulfonic
acid process, sulfuric acid process, or Oleum process. Preparation
via SO.sub.3 air stream in a falling film reactor is a preferred
sulfation process.
[0045] Monomethyl branched anionic surfactants include but are not
limited to the branched anionic sulfates derived from Safol .TM.
23-n and Neodol .TM. 23-n as previously described, where n is an
integer between 1 and about 20. Fractional alkloxylation is also
useful, for example by stoichiometrically adding only about 0.3
moles EO, or 1.5 moles EO, or 2.2 moles EO, based on the moles of
alcohol present, since the molecular combinations that result are
in fact always distributions of alkoxylates so that representation
of n as an integer is merely an average representation. Preferred
monomethyl branched anionic surfactants include a C.sub.12-13 alkyl
sulfate derived from the sulfation of Safol .TM. 23, which has
about 28% branched anionic surfactant molecules; and a C12-13
pareth sulfate derived from Neodol .TM. 23-3, which has about
10-18% branched anionic surfactant molecules.
[0046] When the anionic surfactant is a branched anionic primary
sulfate, it may contain some of the following branched anionic
surfactant molecules: 4-methyl undecyl sulfate, 5-methyl undecyl
sulfate, 7-methyl undecyl sulfate, 8-methyl undecyl sulfate,
7-methyl dodecyl sulfate, 8-methyl-dodecyl sulfate, 9-methyl
dodecyl sulfate, 4,5-dimethyl decyl sulfate, 6,9-dimethyl decyl
sulfate, 6,9-dimethyl undecyl sulfate, 5-methyl-8-ethyl undecyl
sulfate, 9-methyl undecyl sulfate, 5,6,8-trimethyl decyl sulfate,
2-methyl dodecyl sulfate, and 2-methyl undecyl sulfate,. When the
anionic surfactant is a primary alkoxylated sulfate, these same
molecules may be present as the n=0 unreacted alcohol sulfates, in
addition to the typical alkoxylated adducts that result from
alkoxylation (e.g., Neodol .TM. 23-3 mol EO retains typically 16%
unreacted Neodol .TM. 23 with 57% of molecules having 1 to 5 EO
molecules reacted, according to Shell Chemicals technical
literature, `Typical Distributions of NEODOL Ethoxylate
Adducts").
Second Visually Distinct Phase:
[0047] The second visually distinct phase is distinguishable from
the first visually distinct phase by having a different color,
opacity may comprise a structured surfactant or a non-lathering
structured Aqueous Phase.
[0048] The second visually distinct phase may comprise a structured
surfactant identical to the structured surfactant in the first
visually distinct phase; described in detail above.
[0049] The second visually distinct phase of the multi-phase
personal care compositions of the present invention can comprise a
structured aqueous phase that comprises a water structurant and
water. The structured aqueous phase can be hydrophilic and in a
preferred embodiment the structured aqueous phase is a hydrophilic,
non-lathering gelled water phase. In addition, the structured
aqueous phase typically comprises less than about 5%, preferably
less than about 3%, and more preferably less than about 1%, by
weight of the structured aqueous phase, of a surfactant. In one
embodiment of the present invention, the structured aqueous phase
is free of lathering surfactant in the formulation. A preferred
structured aqueous phase is a non-lathering structured aqueous
phase as described in published U.S. Patent Application No.
2005/0143269A1 entitled "Multi-phase Personal Cleansing
Compositions Containing A Lathering Cleansing Phase And A
Non-Lathering Structured Aqueous Phase."
[0050] The structured aqueous phase of the present invention can
comprise from about 30% to about 99%, by weight of the structured
aqueous phase, of water. The structured aqueous phase generally
comprises more than about 50%, preferably more than about 60%, even
more preferably more than about 70%, and still more preferably more
than about 80%, by weight of the structured aqueous phase, of
water.
[0051] The structured aqueous phase will typically have a pH of
from about 5 to about 9.5, more preferably about 7. A water
structurant for the structured aqueous phase can have a net
cationic charge, net anionic charge, or neutral charge. The
structured aqueous phase of the present compositions can further
comprise optional ingredients such as, pigments, pH regulators
(e.g. triethanolamine), and preservatives.
[0052] The structured aqueous phase can comprise from about 0.1% to
about 30%, preferably from about 0.5% to about 20%, more preferably
from about 0.5% to about 10%, and even more preferably from about
0.5% to about 5%, by weight of the structured aqueous phase, of a
water structurant.
[0053] The water structurant is typically selected from the group
consisting of inorganic water structurants, charged polymeric water
structurants, water soluble polymeric structurants, associative
water structurants, and mixtures thereof. Non-limiting examples of
inorganic water structurants include silicas, polymeric gellants
such as polyacrylates, polyacrylamides, starches, modified
starches, crosslinked polymeric gellants, copolymers, and mixtures
thereof. Non-limiting examples of charged polymeric water
structurants for use in the multi-phase personal care composition
include Acrylates/Vinyl Isodecanoate Crosspolymer (Stabylen 30 from
3V), Acrylates/C10-30 Alkyl Acrylate Crosspolymer (Pemulen TR1 and
TR2), Carbomers, Ammonium Acryloyldimethyltaurate/VP Copolymer
(Aristoflex AVC from Clariant), Ammonium
Acryloyldimethyltaurate/Beheneth-25 Methacrylate Crosspolymer
(Aristoflex HMB from Clariant), Acrylates/Ceteth-20 Itaconate
Copolymer (Structure 3001 from National Starch), Polyacrylamide
(Sepigel 305 from SEPPIC), and mixtures thereof. Non-limiting
examples of water soluble polymeric structurants for use in the
multi-phase personal care composition include cellulose gums and
gel, and starches. Non-limiting examples of associative water
structurants for use in the multi-phase personal care composition
include xanthum gum, gellum gum, pectins, alginates such as
propylene glycol alginate, and mixtures thereof.
Additional Ingredients:
[0054] The phases of the multi-phase personal care composition,
preferably the first visually distinct phase, can further comprise
a polymeric phase structurant. The compositions of the present
invention typically can comprise from about 0.05% to about 10%,
preferably from about 0.1% to about 4%, of a polymeric phase
structurant. Non-limiting examples of polymeric phase structurant
include but are not limited to the following examples: naturally
derived polymers, synthetic polymers, crosslinked polymers, block
copolymers, copolymers, hydrophilic polymers, nonionic polymers,
anionic polymers, hydrophobic polymers, hydrophobically modified
polymers, associative polymers, and oligomers.
[0055] Preferably the polymeric phase structurant can be
crosslinked and further comprise a crosslinking. These polymeric
phase structurant useful in the present invention are more fully
described in U.S. Pat. No. 5,087,445, to Haffey et al., issued Feb.
11, 1992; U.S. Pat. No. 4,509,949, to Huang et al., issued Apr. 5,
1985, U.S. Pat. No. 2,798,053, to Brown, issued Jul. 2, 1957. See
also, CTFA International Cosmetic Ingredient Dictionary, fourth
edition, 1991, pp. 12 and 80.
[0056] The phase of the present compositions, preferably the first
visually distinct phase, optionally can further comprise a liquid
crystalline phase inducing structurant, which when present is at
concentrations ranging from about 0.3% to about 15%, by weight of
the phase, more preferably at from about 0.5% to about 5% by weight
of the phase. Suitable liquid crystalline phase inducing
structurants include fatty acids (e.g. lauric acid, oleic acid,
isostearic acid, linoleic acid) ester derivatives of fatty acids
(e.g. propylene glycol isostearate, propylene glycol oleate,
glyceryl isostearate) fatty alcohols, trihydroxystearin (available
from Rheox, Inc. under the trade name THIXCIN.TM. R). Preferably,
the liquid crystalline phase inducing structurant is selected from
lauric acid, trihydroxystearin, lauryl pyrrolidone, and
tridecanol.
[0057] The structured multi-phase personal care compositions of the
present invention can additionally comprise an organic cationic
deposition polymer in the one or more phases as a deposition aid
for the benefit agents described herein. Suitable cationic
deposition polymers for use in the structured multi-phase personal
care compositions of the present invention contain cationic
nitrogen-containing moieties such as quaternary ammonium or
cationic protonated amino moieties. The cationic protonated amines
can be primary, secondary, or tertiary amines (preferably secondary
or tertiary), depending upon the particular species and the
selected pH of the structured multi-phase personal care
composition. Suitable cationic deposition polymers that would be
useful in the compositions of the present invention are disclosed
in the co-pending and commonly assigned U.S. Patent Application No.
60/628,036 filed on Nov. 15, 2003 by Wagner, et al titled
"Depositable Solids."
[0058] One or more of the phases of the multiphase personal care
composition can comprise a variety of additional optional
ingredients such as shiny particles, beads, exfoliating beads. Such
optional ingredients are most typically those materials approved
for use in cosmetics and that are described in reference books such
as the CTFA Cosmetic Ingredient Handbook, Second Edition, The
Cosmetic, Toiletries, and Fragrance Association, Inc. 1988,
1992.
[0059] Other non limiting examples of these optional ingredients
include vitamins and derivatives thereof (e.g., ascorbic acid,
vitamin E, tocopheryl acetate, and the like), sunscreens;
thickening agents, preservatives for maintaining the anti microbial
integrity of the cleansing compositions, anti-acne medicaments,
antioxidants, skin soothing and healing agents such as aloe vera
extract, allantoin and the like, chelators and sequestrants, skin
lightening agents, and agents suitable for aesthetic purposes such
as fragrances, essential oils, skin sensates, pigments, pearlescent
agents and essential oils and fragrance.
[0060] The preferred pH range of the structured multi-phase
personal care composition is from about 5 to about 8.
Test Methods:
Yield Stress and Zero Shear Viscosity Method:
[0061] The Yield Stress and Zero Shear Viscosity of a phase of the
present composition, can be measured either prior to combining in
the composition, or after combining in the composition by
separating the phase by suitable physical separation means, such as
centrifugation, pipetting, cutting away mechanically, rinsing,
filtering, or other separation means.
[0062] A controlled stress rheometer such as a TA Instruments
AR2000 Rheometer is used to determine the Yield Stress and Zero
Shear Viscosity. The determination is performed at 25.degree. C.
with the 4 cm diameter parallel plate measuring system and a 1 mm
gap. The geometry has a shear stress factor of 79580 m.sup.-3 to
convert torque obtained to stress.
[0063] First a sample of the phase is obtained and placed in
position on the rheometer base plate, the measurement geometry
(upper plate) moving into position 1 mm above the base plate.
Excess phase at the geometry edge is removed by scraping after
locking the geometry. If the phase comprises particles discernible
to the eye or by feel (beads, e.g.) which are larger than about 150
microns in number average diameter, the gap setting between the
base plate and upper plate is increased to the smaller of 4 mm or
8-fold the diameter of the 95.sup.th volume percentile particle
diameter. If a phase has any particle larger than 5 mm in any
dimension, the particles are removed prior to the measurement.
[0064] The determination is performed via the programmed
application of a continuous shear stress ramp from 0.1 Pa to 1,000
Pa over a time interval of 5 minutes using a logarithmic
progression, i.e., measurement points evenly spaced on a
logarithmic scale. Thirty (30) measurement points per decade of
stress increase are obtained. Stress, strain and viscosity are
recorded. If the measurement result is incomplete, for example if
material flows from the gap, results obtained are evaluated and
incomplete data points excluded. The Yield Stress is determined as
follows. Stress (Pa) and strain (unitless) data are transformed by
taking their logarithms (base 10). Log(stress) is graphed vs.
log(strain) for only the data obtained between a stress of 0.2 Pa
and 2.0 Pa, about 30 points. If the viscosity at a stress of 1 Pa
is less than 500 Pa-sec but greater than 75 Pa-sec, then
log(stress) is graphed vs. log(strain) for only the data between
0.2 Pa and 1.0 Pa, and the following mathematical procedure is
followed. If the viscosity at a stress of 1 Pa is less than 75
Pa-sec, the zero shear viscosity is the median of the 4 highest
viscosity values (i.e., individual points) obtained in the test,
the yield stress is zero, and the following mathematical procedure
is not used. The mathematical procedure is as follows. A straight
line least squares regression is performed oh the results using the
logarithmically transformed data in the indicated stress region, an
equation being obtained of the form: (1)
Log(strain)=m*Log(stress)+b
[0065] Using the regression obtained, for each stress value (i.e.,
individual point) in the determination between 0.1 and 1,000 Pa, a
predicted value of log(strain) is obtained using the coefficients m
and b obtained, and the actual stress, using Equation (1). From the
predicted log(strain), a predicted strain at each stress is
obtained by taking the antilog (i.e., 10.sup.x for each x). The
predicted strain is compared to the actual strain at each
measurement point to obtain a % variation at each point, using
Equation (2). (2) % variation=100*(measured strain-predicted
strain)/measured strain
[0066] The Yield Stress is the first stress (Pa) at which %
variation exceeds 10% and subsequent (higher) stresses result in
even greater variation than 10% due to the onset of flow or
deformation of the structure. The Zero Shear Viscosity is obtained
by taking a first median value of viscosity in Pascal-seconds
(Pa-sec) for viscosity data obtained between and including 0.1 Pa
and the Yield Stress. After taking the first median viscosity, all
viscosity values greater than 5-fold the first median value and
less than 0.2.times.the median value are excluded, and a second
median viscosity value is obtained of the same viscosity data,
excluding the indicated data points. The second median viscosity so
obtained is the Zero Shear Viscosity.
Lather Volume Test:
[0067] Lather volume of a first visually distinct phase, a
structured surfactant component or a structured domain of a
structured multi-phase personal care composition, is measured using
a graduated cylinder and a rotating apparatus. A 1,000 ml graduated
cylinder is used which is marked in 10 ml increments and has a
height of 14.5 inches at the 1,000 ml mark from the inside of its
base (for example, Pyrex No. 2982). Distilled water (100 grams at
25.degree. C.) is added to the graduated cylinder. The cylinder is
clamped in a rotating device, which clamps the cylinder with an
axis of rotation that transects the center of the graduated
cylinder. Inject 0.50 grams of a structured surfactant component or
first visually distinct phase from a syringe (weigh to ensure
proper dosing) into the graduated cylinder onto the side of the
cylinder, above the water line, and cap the cylinder. When the
sample is evaluated, use only 0.25 cc, keeping everything else the
same. The cylinder is rotated for 20 complete revolutions at a rate
of about 10 revolutions per 18 seconds, and stopped in a vertical
position to complete the first rotation sequence. A timer is set to
allow 15 seconds for lather generated to drain. After 15 seconds of
such drainage, the first lather volume is measured to the nearest
10 ml mark by recording the lather height in ml up from the base
(including any water that has drained to the bottom on top of which
the lather is floating).
[0068] If the top surface of the lather is uneven, the lowest
height at which it is possible to see halfway across the graduated
cylinder is the first lather volume (ml). If the lather is so
coarse that a single or only a few foam cells which comprise the
lather ("bubbles") reach across the entire cylinder, the height at
which at least 10 foam cells are required to fill the space is the
first lather volume, also in ml up from the base. Foam cells larger
than one inch in any dimension, no matter where they occur, are
designated as unfilled air instead of lather. Foam that collects on
the top of the graduated cylinder but does not drain is also
incorporated in the measurement if the foam on the top is in its
own continuous layer, by adding the ml of foam collected there
using a ruler to measure thickness of the layer, to the ml of foam
measured up from the base. The maximum lather height is 1,000 ml
(even if the total lather height exceeds the 1,000 ml mark on the
graduated cylinder). 30 seconds after the first rotation is
completed, a second rotation sequence is commenced which is
identical in speed and duration to the first rotation sequence. The
second lather volume is recorded in the same manner as the first,
after the same 15 seconds of drainage time. A third sequence is
completed and the third lather volume is measured in the same
manner, with the same pause between each for drainage and taking
the measurement.
[0069] The lather results after each sequence are added together
and the Total Lather Volume determined as the sum of the three
measurements, in milliters ("ml"). The Flash Lather Volume is the
result after the first rotation sequence only, in ml, i.e., the
first lather volume. Compositions according to the present
invention perform significantly better in this test than similar
compositions in conventional emulsion form.
Ultracentrifugation Method:
[0070] The Ultracentrifugation Method is used to determine the
percent of a structured domain or an opaque structured domain that
is present in a structured multi-phase personal care composition
that comprises a first visually distinct phase comprising a
structured surfactant component. The method involves the separation
of the composition by ultracentrifugation into separate but
distinguishable layers. The structured multi-phase personal care
composition of the present invention can have multiple
distinguishable layers, for example a non-structured surfactant
layer, a structured surfactant layer, and a benefit layer.
[0071] First, dispense about 4 grams of multi-phase personal care
composition into Beckman Centrifuge Tube (11.times.60 mm). Next,
place the centrifuge tubes in an Ultracentrifuge (Beckman Model
L8-M or equivalent) and ultracentrifuge using the following
conditions: 50,000 rpm, 18 hours, and 25.degree. C.
[0072] After ultracentrifuging for 18 hours, determine the relative
phase volume by measuring the height of each layer visually using
an Electronic Digital Caliper (within 0.01 mm). First, the total
height is measured as H.sub.a which includes all materials in the
ultracentrifuge tube. Second, the height of the benefit layer is
measured as H.sub.b. Third, the structured surfactant layer is
measured as H.sub.c. The benefit layer is determined by its low
moisture content (less than 10% water as measured by Karl Fischer
Titration). It generally presents at the top of the centrifuge
tube. The total surfactant layer height (H.sub.s) can be calculated
by this equation: H.sub.s=H.sub.a-H.sub.b
[0073] The structured surfactant layer components may comprise
several layers or a single layer. Upon ultracentrifugation, there
is generally an isotropic layer at the bottom or next to the bottom
of the ultracentrifuge tube. This clear isotropic layer typically
represents the non-structured micellar surfactant layer. The layers
above the isotropic phase generally comprise higher surfactant
concentration with higher ordered structures (such as liquid
crystals). These structured layers are sometimes opaque to naked
eyes, or translucent, or clear. There is generally a distinct phase
boundary between the structured layer and the non-structured
isotropic layer. The physical nature of the structured surfactant
layers can be determined through microscopy under polarized light.
The structured surfactant layers typically exhibit distinctive
texture under polarized light. Another method for characterizing
the structured surfactant layer is to use X-ray diffraction
technique. Structured surfactant layer display multiple lines that
are often associated primarily with the long spacings of the liquid
crystal structure. There may be several structured layers present,
so that H.sub.c is the sum of the individual structured layers. If
a coacervate phase or any type of polymer-surfactant phase is
present, it is considered a structured phase.
[0074] Finally, the structured domain volume ratio is calculated as
follows: Structured Domain Volume Ratio=H.sub.c/H.sub.s*100%
[0075] If there is no benefit phase present, use the total height
as the surfactant layer height, H.sub.s=H.sub.a.
T- Bar Method for Assessing Structured Surfactant Stability In
Presence of Lipid
[0076] The stability of a surfactant-containing phase ("cleansing
phase" or "first visually distinct phase") in the presence of lipid
can be assessed using a T-Bar Viscosity Method. The apparatus for
T-Bar measurement includes a Brookfield DV-II+ Pro Viscometer with
Helipath Accessory; chuck, weight and closer assembly for T-bar
attachment; a T-bar Spindle D, a personal computer with Rheocalc
software from Brookfield, and a cable connecting the Brookfield
Viscometer to the computer. First, weigh 40 grams of the cleansing
phase in a 4-oz glass jar. Centrifuge the jar at 2,000 rpm for 20
min to de-aerate the cleansing phase, which may also remove large
particles by sedimentation or flotation. Measure the height of the
cleansing phase "H.sub.surf" using an Electronic Caliper with a
precision of 0.01 mm. Measure the initial T-bar viscosity by
carefully dropping the T-Bar Spindle to the interior bottom of the
jar and set the Helipath stand to travel in an upward direction.
Open the Rheocalc software and set the following data acquisition
parameters: set Speed to 5 rpm, set Time Wait for Torque to 00:01
(1 second), set Loop Start Count at 40. Start data acquisition and
turn on the Helipath stand to travel upward at a speed of 22
mm/min. The initial T-Bar viscosity "T.sub.ini," is the average
T-Bar viscosity reading between the 6.sup.th reading and the
35.sup.th reading (the first five and the last five readings are
not used for the average T-Bar viscosity calculation). Cap the jar
and store at ambient temperature. Prepare a separate lipid blend by
heating a vessel to 180.degree. F. (82.2.degree. C.) and add
together 70 parts of Petrolatum (G2218 from WITCO) and 30 parts of
Hydrobrite 1000 White Mineral Oil. Cool the vessel to 110.degree.
F. (43.3.degree. C.) with slow agitation (200 rpm). Stop agitation
and cool the vessel to ambient temperature overnight. Add 40 grams
of the lipid blend (70/30 Pet/MO) to the jar containing the first
visually distinct phase. Stir the first visually distinct phase and
lipid together using a spatula for 5 min. Place the jar at
113.degree. F. (45.degree. C.) for 5 days. After 5 days, centrifuge
the jar at 2000 rpm for 20 min (do not cool the jar first).
[0077] After centrifugation, cool down the jar and contents to
ambient conditions, overnight. Observe the contents of the jar. A
stable cleansing phase exhibits a uniform layer at the bottom of
the jar, below the less dense petrolatum/oil phase. An unstable
cleansing phase can form layers not present in the originally
centrifuged cleansing phase (i.e., an isotropic phase) either at
the bottom or between the cleansing phase-lipid interface. If more
than one layer is present in the cleansing phase, measure the
height of each newly formed layer, "H.sub.new" using an Electronic
Caliper. Add together the heights of all the newly formed layers.
The new phase volume ratio is calculated as
H.sub.new/H.sub.surf*100% , using the height of all new layers
added together as H.sub.new. Preferably, a stable structured
cleansing phase forms less than 10% of new phase volume. More
preferably, a stable structured cleansing phase forms less than 5%
of new phase volume. Most preferably, a stable structured cleansing
phase forms 0% of new phase volume.
[0078] The T-Bar viscosity of the centrifuged contents of the jar
is then measured using the T-Bar method above. Open the Rheocalc
software and set the following data acquisition parameters: set
Speed to 5 rpm, set Time Wait for Torque to 00:01 (1 second), set
Loop Start Count at 80. Start the data acquisition and turn on the
Helipath stand to travel upward at a speed of 22 mm/min. There is
usually a distinctive viscosity jump between the first visually
distinct phase layer and the lipid layer. The average cleansing
phase T-Bar viscosity after lipid exposure, "T.sub.aft" is the
average reading between the 6.sup.th T-Bar viscosity and the last
T-Bar viscosity reading before the jump in viscosity due to the
lipid layer. In the case where there is no distinctive T-Bar
viscosity jump between cleansing phase and lipid phase, only use
the average reading between the 6.sup.th T-Bar viscosity reading
and the 15.sup.th reading as the average cleansing phase T-bar
viscosity, T.sub.aft. Preferably, a stable structured cleansing
phase has T.sub.aft higher than 10,000 cP. More preferably, a
stable structured cleansing phase has T.sub.aft higher than 15,000
cP. Most preferably, a stable structured first visually distinct
phase has T.sub.aft higher than 20,000 cP Viscosity Retention is
calculated as T.sub.aft/T.sub.ini*100%. Preferably, a stable
structured cleansing phase has >50% Viscosity Retention. More
preferably, a stable structured cleansing phase has >70%
Viscosity Retention. Most preferably, a stable structured cleansing
phase has >80% Viscosity Retention.
Method of Use:
[0079] The multi-phase personal care compositions of the present
invention are preferably applied topically to the desired area of
the skin or hair in an amount sufficient to provide effective
delivery of the skin cleansing agent, hydrophobic material, and
particles to the applied surface. The compositions can be applied
directly to the skin or indirectly via the use of a cleansing puff,
washcloth, sponge or other implement. The compositions are
preferably diluted with water prior to, during, or after topical
application, and then subsequently the skin or hair rinsed or wiped
off, preferably rinsed off of the applied surface using water or a
water-insoluble substrate in combination with water.
[0080] The present invention is therefore also directed to methods
of cleansing the skin through the above-described application of
the compositions of the present invention. The methods of the
present invention are also directed to a method of providing
effective delivery of the desired skin active agent, and the
resulting benefits from such effective delivery as described
herein, to the applied surface through the above-described
application of the compositions of the present invention.
Method of Manufacture:
[0081] The multi-phase personal care compositions of the present
invention may be prepared by any known or otherwise effective
technique, suitable for making and formulating the desired
multi-phase product form. It is effective to combine
toothpaste-tube filling technology with a spinning stage design.
Additionally, the present invention can be prepared by the method
and apparatus as disclosed in U.S. Pat. No. 6,213,166 issued to
Thibiant, et al on Apr. 10, 2001. The method and apparatus allows
two or more compositions to be filled with a spiral configuration
into a single container. The method requires that at least two
nozzles be employed to fill the container. The container is placed
on a static mixer and spun as the composition is introduced into
the container.
[0082] Alternatively, it is effective to combine at least two
phases by first placing the separate compositions in separate
storage tanks having a pump and a hose attached. The phases are
then pumped in predetermined amounts into a single combining
section. Next, the phases are moved from the combining sections
into the blending sections and the phases are mixed in the blending
section such that the single resulting product exhibits a distinct
pattern of the phases. The pattern is selected from the group
consisting of striped, marbled, geometric, and mixtures thereof.
The next step involves pumping the product that was mixed in the
blending section via a hose into a single nozzle, then placing the
nozzle into a container and filing the container with the resulting
product. Specific non-limiting examples of such methods as they are
applied to specific embodiments of the present invention are
described in the following examples.
[0083] If the multi-phase personal care compositions are patterned,
it can be desirable to be packaged as a personal care article. The
personal care article would comprise these compositions in a
transparent or translucent package such that the consumer can view
the pattern through the package. Because of the viscosity of the
subject compositions it may also be desirable to include
instructions to the consumer to store the package upside down, on
its cap to facilitate dispensing.
[0084] It should be understood that every maximum numerical
limitation given throughout this specification includes every lower
numerical limitation, as if such lower numerical limitations were
expressly written herein. Every minimum numerical limitation given
throughout this specification includes every higher numerical
limitation, as if such higher numerical limitations were expressly
written herein. Every numerical range given throughout this
specification includes every narrower numerical range that falls
within such broader numerical range, as if such narrower numerical
ranges were all expressly written herein.
[0085] All parts, ratios, and percentages herein, in the
Specification, Examples, and Claims, are by weight and all
numerical limits are used with the normal degree of accuracy
afforded by the art, unless otherwise specified.
EXAMPLES
[0086] The following first visually distinct phases are prepared as
non-limiting examples (chemical content is shown). Examples 1 and 2
are Comparative Examples of the first visually distinct phase of
the present invention. Examples 3-7 are examples of the first
visually distinct phase of the present invention. Examples 8, 9 and
10 are Comparative Examples. Examples 11 and 12 are examples of
structured aqueous phase of the present invention.
[0087] Examples 1 and 2 are comparative examples of the first
visually distinct phase of the present invention which comprise all
linear anionic surfactants. Examples 3-5 are examples of the
present invention comprising a mix of linear and branched anionic
surfactants. Of the mixed anionic surfactant compositions Examples
3-5, compositions with lower sodium trideceth sulfate exhibited
higher flash and total lather volumes. However, mixtures of
branched and linear anionic surfactant (Examples 3-5) exhibited
higher flash and total lather volume than all linear anionic
compositions (Comparative Examples 1 and 2), and improved
stability. TABLE-US-00002 First visually distinct Comparative
Example phase example: 1 2 3 4 5 Water, distilled QS QS QS QS QS
Skin Benefit Components and Thickeners Water, distilled QS QS QS QS
QS Glycerin 0.3 0.3 1.93 -- -- Guar hydroxypropropyl-trimonium
chloride(N- 0.4 0.4 0.2 0.6 0.6 Hance 3196 - Aqualon or Jaguar
C-17, Rhodia) PEG 90M (Polyox WSR 301, Amerchol Corp) 0.10 0.10
0.15 0.15 0.15 Citric acid -- -- 0.25 0.25 0.25 Structured
surfactant components Sodium trideceth sulfate (Cedepal TD403, --
-- 6.17 7.9 7.9 Stepan) Ammonium Lauryl Sulfate (P&G) 13.4 9.40
9.26 7.9 7.9 Sodium Lauroamphoacetate (Miranol L-32, -- -- 4.57 4.7
4.7 Rhodia) Polyoxyethylene 2.5 lauryl alcohol (Arylpon F, 3.0 2.1
-- -- -- Cognis Corp, Cincinnati, OH) Cocamidopropyl betaine
(Tegobetaine F, 3.7 2.6 -- -- -- DeGussa) Isosteareth-2 (Hetoxol
IS-2, Global Seven, -- -- 1.0 1.0 1.0 USA) Preservative and Minors
Fragrance/perfume 1.4 1.4 1.54 1.54 1.44 Sodium chloride 3.5 3.5
3.5 3.5 3.5 Disodium EDTA 0.06 0.06 0.12 0.12 0.12 DMDM Hydantoin
(Glydant) 0.73 0.73 0.37 0.37 0.37 Sodium benzoate -- -- 0.2 0.2
0.2 Expancel 091 DE d30 microspheres (Akzo 0.3 0.3 0.3 0.3 0.3
Nobel; Expancel, Inc.) Polymeric Phase Structurants Xanthan gum
(Keltrol CGT, Kelco) 0.13 0.26 0.4 0.2 0.2 Acrylates/Vinyl
Isodecanoate Crosspolymer 0.27 0.54 -- -- -- (Stabylen 30 from 3V)
Final pH (adjust using NaOH or citric acid) 5.9 5.9 6.0 6.0 6.0
Total surfactant, % of first visually distinct 20.1 14.1 21.0 21.5
21.5 phase Anionic surfactant, % of structured surfactant 67 67 74
74 74 component Mono methyl branched anionic surfactant, % of 0 0 0
0 0 anionic surfactant Branched anionic surfactant, % of anionic 0
0 40 50 50 surfactant Zero shear viscosity, Pa-sec 6800 7600 8100
4900 5700 Yield stress, Pa 14 Lather Volume of first visually
distinct phase: 490/1810 500/1930 650/2340 540/2150 510/2020
Flash/Total (ml/ml) Structured Domain Volume Ratio 64 52 91 86 88
Stability: % Third Phase 0 6 0 0 0 T-bar % viscosity change -23 -37
-18 -15 -7
[0088] Examples 8-10 are Comparative Examples. Example 8 does not
comprise branched anionic surfactants. Comparative Examples 9 and
10 comprise higher sodium trideceth sulfate than in the claimed
range. Examples 6 and 7, having lower sodium trideceth sulfate than
Comparative Examples 9 and 10, which have greater than 10% sodium
trideceth sulfate, have higher flash and total lather volumes.
Comparative Example 8, which does not have any branched
surfactants, is not stable, and also does not have lather volumes
as high as Examples 6 and 7, which have both branched and linear
anionic surfactants. TABLE-US-00003 First visually distinct phase
Example: Comparative Example 6 7 8 9 10 Water, distilled QS QS QS
QS QS Skin Benefit Components and Thickeners Water, distilled QS QS
QS QS QS Glycerin 0.21 0.3 0.5 0.5 Guar hydroxypropropyl-trimonium
chloride(N- 0.45 0.47 0.4 0.45 0.45 Hance 3196 - Aqualon or Jaguar
C-17, Rhodia) PEG 90M (Polyox WSR 301) 0.15 0.07 0.1 0.08 0.08
Citric acid 0.25 0.25 0.2 0.2 0.2 Structured surfactant components
Sodium trideceth sulfate (Cedepal TD-403) 5.6 5.56 -- 10.3 10.3
Safol 23 sulfate, sodium salt 5.56 -- -- -- Ammonium Lauryl Sulfate
(P&G) 8.4 -- -- -- -- Ammonium Laureth Sulfate (P&G, 3 mol
EO) -- -- 9.4 -- -- Cocamide monoethanolamine -- -- -- 2.1 2.1
Sodium Lauroamphoacetate (Miranol L-32) 3.0 -- -- 3.3 3.3
Polyoxyethylene 2.5 lauryl alcohol (Arylpon F) 0.75 2.35 2.1 -- --
Cocamidopropyl betaine (Tegobetaine F) 3.35 2.58 -- --
Isosteareth-2 (Hetoxol IS-2) 1.0 1.0 -- -- -- Preservative and
Minors Fragrance/perfume 1.44 1.54 1.4 1.25 1.25 Sodium chloride
3.5 3.5 3.5 2.8 2.8 Disodium EDTA 0.12 0.12 0.06 -- -- DMDM
Hydantoin (Glydant) 0.37 0.37 0.7 0.25 0.25 Sodium benzoate 0.2 0.2
-- -- -- Expancel 091 DE d30 microspheres 0.3 0.3 0.3 -- --
Polymeric Phase Structurants Xanthan gum (Keltrol CGT, Kelco) 0.4
0.66 0.26 -- -- Acrylates/Vinyl Isodecanoate Crosspolymer -- --
0.54 0.5 0.8 (Stabylen 30 from 3V) Final pH (adjust to) 6.0 6.2 5.9
6.7 5.8 Total surfactant, % of surfactant phase 18.8 17.8 14.1 15.7
15.7 Anionic surfactant, % of structured surfactant 75 62 67 56 56
component Mono methyl branched anionic surfactant, % of 0 50 0 0 0
anionic surfactant Branched anionic surfactant, % of anionic 40 100
0 100 100 surfactant Zero shear viscosity, Pa-sec 4600 4500 900
3300 8700 Lather Volume of first visually distinct phase: 590/2250
520/1910 470/1920 490/1840 460/1800 Flash/Total (ml/ml) Structured
Domain Volume Ratio 87 Stability: % Third Phase 0 0 5% 0 T-bar %
viscosity change -20 -29 -79 -30
[0089] The first visually distinct phase can be prepared by
conventional mixing techniques. Prepare the first visually distinct
phase by first adding the water, skin benefit components and
thickeners into a vessel, agitating until a dispersion is formed.
Then add in the following sequence: surfactants, Disodium EDTA,
preservative, half the sodium chloride and all other minors except
fragrance and the withheld sodium chloride. Heat to 65-70.degree.
C. if Cocamide monoethanolamine is used, otherwise maintain at
ambient temperature while agitating the mixing vessel. Cool to 45 C
if heating was used. For additional stability, gas filled
microspheres having a density of about 30 kg/m.sup.3 such as
Expancel 091 DE 40 d30 (from Expancel, Inc.) can optionally be used
at about 0.1-0.5% of the batch. In a separate vessel, prewet the
structuring polymers with fragrance and add to the mix vessel at
the same time as the remaining sodium chloride while agitating.
Agitate until homogeneous, then pump through a static mixing
element to disperse any lumps to complete the batch.
Structured Aqueous Phase
[0090] The Structured Aqueous Phase of Examples 11-12 can be
prepared by dispersing polymers in water with high shear, adding
salt and remaining ingredients except petrolatum and mineral oil,
neutralizing to pH 7.0 with triethanolamine (approximate TEA level
is shown), heating to 50.degree. C., adding the petrolatum and
mineral oil as a liquid at 80.degree. C., and agitating until
homogeneous without high shear. Pigments having no water soluble
components are preferably used. A particle size of about 5-100
microns for the petrolatum component is obtained for most of the
particles. TABLE-US-00004 Structured Aqueous Phase (non-lathering)
Example: 11 12 Water, distilled QS QS Acrylates/Vinyl Isodecanoate
Crosspolymer 1.0 0.8 (Stabylen 30 from 3V) Xanthan gum (Keltrol CGT
or Keltrol 1000 1.0 0.8 from Kelco) DMDM Hydantoin, preservative
0.4 0.4 EDTA 0.05 0.04 Mineral oil (Hydrobrite 1000, Witco) 0.03
4.82 Petrolatum (Super White Protopet, Witco) 20.0 18.78
Triethanolamine 0.80 0.80 Sodium chloride 3.0 2.4 Pigment 0.35
0.35
Visually Distinct Compositions
[0091] Visually distinct compositions are prepared by first
preparing two compositions that differ in appearance. A first
visually distinct phases of Examples 3-7 is selected (any can be
selected) and pigmented using a hydrophobic pigment, which keeps
color from leaching. A second first visually distinct phase of
Examples 3-7 and 11-12 can be selected and either pigmented to a
different color, pigmented white, or not pigmented, such that the
phase visually differs from the first phase chosen, including by
being, e.g., a transparent gel. The phases are added to separate
hoppers and gravity fed to a package (e.g., bottle, tube, etc.)
filling operation. The phases are maintained at ambient temperature
and are simultaneously pumped in a specified volumetric ratio
through 3/4 in. diameter pipes containing a single element static
mixer (Koch/SMX type), the single pipe exits into a 10 oz. bottle
on a spinning platform. The platform is set to 200 rpm spin speed,
the composition filling 315 ml in about 2 seconds, the spinning
platform being lowered during filling so that filling proceeds in a
layering fashion from bottom to top. A relatively horizontal
striped pattern is obtained. By adjusting temperature and viscosity
of the phases, static mixer element types and number of elements
(including no elements), pipe diameters, spin rates, etc., a wide
variety of patterns is obtained. One or both of the phases can be a
benefit phase, or a combined benefit phase, by preparing an
emulsion or a dispersion with the phase using conventional
techniques to prepare an emulsion or dispersion with a dispersed
phase such as petrolatum, mineral oil, other synthetic and natural
oils such as jojoba, shea butter, triglyceride, lanolin, ethers,
esters including emollient sucrose esters, ethers, waxes, silicone
fluids, polymers including polymeric esters such as polyglyceryl
esters, mixtures and combinations of these and other hydrophobic
materials having a Vaughn Solubility Parameter less than about 13
(cal/cm.sup.3).sup.1/2. When mixtures of such hydrophobic materials
are used, they can be prepared by combining the hydrophobic
materials first at an elevated temperature, such as is done in
traditional emulsion preparation, or they can be added separately,
either with heat or without, in a batch, semi-batch, or continuous
process to the hydrophilic phase. Colorant, pigment or whitener can
be added to the dispersed phase or to either of the hydrophilic
continuous phases. To optimize benefit phase efficacy and/or
appearance, any of the Examples 3-7 can be diluted to a lower
surfactant concentration, e.g. to 10%, or 6%, or 4% or even less
than 1% surfactant so long as the phase remains continuously
hydrophilic and the rheology of the phase sufficient so the
visually distinct composition remains stable. The hydrophobic
material can also be dispersed in a non-lathering structured
aqueous phase, for example the non-lathering structured aqueous
phase of Examples 1 or 12, as shown. The benefit phase can thus be
lathering, or non-lathering. If the surfactant level is reduced in
one of the phases, rheology can be adjusted using traditional
thickeners, for example water soluble polymers, cross-linked water
swellable polymers, clays, gel networks, etc., as is known to one
with ordinary skill in the art. Additionally, surfactant can be
concentrated in one of the phases by reducing water content, so
that the surfactant concentration is 24%, 30%, 40%, 50% or even as
high as 75% of one or more of the phases in order to deliver
efficient cleansing from a low level of a concentrated surfactant
phase. Typically, levels of electrolyte (e.g., salt), thickeners
and cationic polymer would be adjusted for viscosity control. In
some cases, it may be preferred to increase viscosity, for example
so that the Zero Shear Viscosity is greater than 15,000 Pa-sec,
even greater than 25,000 Pa-sec, or even greater than 35,000 Pa-sec
in order to provide phases which are visually distinct and
paste-like, such as for example visually distinct concentrates
packaged in tubes, filled by apparati such as multi-phase
toothpaste filling equipment.
[0092] Additionally, the present invention can be prepared by the
method and apparatus as disclosed in U.S. Pat. No. 6,213,166 issued
to Thibiant et, al. on Apr. 10, 2001 which method and apparatus
allows compositions to be filled with a spiral configuration into a
single container using at least 2 nozzles.
[0093] All documents cited in the Detailed Description of the
Invention are, in relevant part, incorporated herein by reference;
the citation of any document is not to be construed as an admission
that it is prior art with respect to the present invention. To the
extent that any meaning or definition of a term in this written
document conflicts with any meaning or definition of the term in a
document incorporated by reference, the meaning or definition
assigned to the term in this written document shall govern.
[0094] While particular embodiments of the present invention have
been illustrated and described, it would be obvious to those
skilled in the art that various other changes and modifications can
be made without departing from the spirit and scope of the
invention. It is therefore intended to cover in the appended claims
all such changes and modifications that are within the scope of
this invention.
* * * * *