U.S. patent application number 11/454809 was filed with the patent office on 2007-07-05 for structured multi-phased personal cleansing composition comprising branched anionic surfactants.
Invention is credited to Mark Richard Sine, Edward Dewey III Smith, Robert John Strife, Scott William Syfert, Karl Shiqing Wei.
Application Number | 20070155637 11/454809 |
Document ID | / |
Family ID | 36686004 |
Filed Date | 2007-07-05 |
United States Patent
Application |
20070155637 |
Kind Code |
A1 |
Smith; Edward Dewey III ; et
al. |
July 5, 2007 |
Structured multi-phased personal cleansing composition comprising
branched anionic surfactants
Abstract
A multi-phase personal cleansing composition is described that
comprises a first visually distinct phase including a structured
surfactant component and a second visually distinct phase
comprising a benefit phase comprising an emulsion. 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) ; Sine; Mark
Richard; (New Richmond, OH) |
Correspondence
Address: |
THE PROCTER & GAMBLE COMPANY;INTELLECTUAL PROPERTY DIVISION - WEST BLDG.
WINTON HILL BUSINESS CENTER - BOX 412
6250 CENTER HILL AVENUE
CINCINNATI
OH
45224
US
|
Family ID: |
36686004 |
Appl. No.: |
11/454809 |
Filed: |
June 16, 2006 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11400359 |
Apr 7, 2006 |
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11454809 |
Jun 16, 2006 |
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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 8/42 20130101; A61K
8/06 20130101; A61K 8/11 20130101; A61K 2800/412 20130101; A61Q
19/10 20130101; A61K 8/03 20130101; A61Q 5/02 20130101 |
Class at
Publication: |
510/130 |
International
Class: |
A61K 8/00 20060101
A61K008/00 |
Claims
1. A multi-phase personal cleansing composition comprising: a first
visually distinct phase comprising a structured surfactant
component; and a second visually distinct phase comprises a benefit
phase comprising an emulsion; 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 cleansing 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 cleansing 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 cleansing 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 cleansing 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 cleansing 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 cleansing composition of claim 6,
wherein said branched anionic surfactant comprises monomethyl
branched sulfated derivatives of hydrocarbons.
8. The multi-phase personal cleansing 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 cleansing composition of claim 1,
wherein said composition further comprises a polymeric phase
structurant.
10. The multi-phase personal cleansing composition of claim 1,
wherein said first visually distinct phase and said second visually
distinct phase form a pattern.
11. The multi-phase personal cleansing composition of claim 10
wherein the pattern is selected from the group consisting of
striped, geometric, marbled, and combinations thereof.
12. The multi-phase personal cleansing composition of claim 11,
wherein said composition is packaged in a container such that said
pattern is visible.
13. The multi-phase personal cleansing composition of claim 1,
wherein said benefit phase is a water in oil emulsion.
14. The multi-phase personal cleansing composition of claim 1,
wherein said benefit phase is an oil in water emulsion.
15. The multi-phase personal cleansing composition of claim 1,
wherein said second visually distinct phase further comprises an
emulsifier.
16. The multi-phase personal cleansing composition of claim 1,
wherein said second visually distinct phase further comprises a low
HLB emulsifier.
17. The multi-phase personal cleansing composition of claim 1,
wherein said first visually distinct phase further comprises: (i)
at least one electrolyte; (ii) at least one amphoacetatate
surfactant; (iii) at least one ethoxylated fatty alcohol; and (iv)
water; wherein said first visually distinct phase is non-Newtonian
shear thinning; and wherein said first visually distinct phase has
a viscosity of equal to or greater than about 3000 cps.
18. The multi-phase personal cleansing 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.
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 is a continuation in part of U.S.
application Ser. No. 11/400,359 filed Apr. 7, 2006, pending, that
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 cleansing 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
cleansing composition that comprises a first visually distinct
phase comprising a structured surfactant component; and a second
visually distinct phase that comprises a benefit phase that
comprised an emulsion. 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 cleansing 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 pattern may be relatively
uniform across the dimension of the package; however, the pattern
may be uneven, wavy, or non-uniform in dimension and does not
extend across the entire dimension of the package. If striped, 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 one of the phases in order to offset its
appearance from the other.
[0012] The term "multi-phase personal cleansing composition" as
used herein, refers to compositions intended for topical
application to the skin or hair. Preferably, the compositions of
the present invention are rinse-off formulations, in which the
product is applied topically to the skin or hair and then is
subsequently rinsed within minutes from the skin or hair with
water, or otherwise wiped off using a substrate with deposition of
a portion of the composition. The compositions also may be used as
shaving aids.
[0013] 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 in herein.
[0014] 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.
[0015] 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: [0016] 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 [0017] 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 [0018] 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%.
[0019] As used herein "substantially free" means that the
composition or phase comprises less than about 5%, preferably less
than 3%, preferably less than about 1%, more preferably less than
about 0.5%, more preferably less than about 0.25%,and most
preferably less than about 0.1%, by weight of the composition or
phase of a stated ingredient.
[0020] The term "visually distinct phase" as used herein, refers to
a region of the multi-phase personal cleansing 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.
[0021] Product Form: The multi-phase personal cleansing composition
of the present invention is typically extrudable or dispensable
from a package. The multi-phase personal cleansing 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 serial number 10/841174 filed on
May 7, 2004 titled "Multi-phase Personal Care Compositions."
[0022] When evaluating a structured multi-phase personal cleansing
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 and the composition and distribution of
components therein is not substantially altered by the separation
means, so that it is representative of the component as it exists
in the structured multi-phase personal cleansing composition.
[0023] Phases: The multi-phase personal cleansing compositions of
the present invention comprise at least two phases, but the
compositions, a third phase, a fourth phase and so on. The ratio of
a first phase to a second phase is preferably from about 1:99 to
about 99:1, preferably from about 90:10 to about 10:90, more
preferably from about 80:20 to about 20:80, even more preferably
from about 70:30 to about 30:70, still even more preferably from
about 60:40 to about 40:60, even still even more preferably about
50:50.
[0024] First Visually Distinct Phase: The first visually distinct
phase of a multi-phase personal cleansing composition of the
present invention can comprise a structured surfactant component.
The structured surfactant component a mixture of surfactants and
comprises at least of branched anionic surfactant and from 0 to 10%
by weight of the first visually distinct phase, of sodium trideceth
sulfate. The structured surfactant component typically comprises
from about 1% to about 99%, and more preferably from about 20% to
about 50%, by weight of the composition, of the first visually
distinct phase.
[0025] Structured surfactant component: The multi-phase personal
cleansing 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.
[0026] 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 herein.
[0027] 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 which is
preferably a lamellar phase that preferably 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.
[0028] 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 which are otherwise compatible with
the other essential ingredients in the multi-phase personal
cleansing composition including water. 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. These surfactants include anionic,
nonionic, cationic, zwitterionic, amphoteric surfactants, soap, or
combinations thereof.
[0029] 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 which may be linear or branched. The first visually
distinct phase or structured surfactant component preferably
comprises at least one branched anionic surfactant. 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. Preferred linear anionic
surfactants for use in the structured surfactant phase of the
multi-phase, personal cleansing 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.
[0030] 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. Branching
information for many surfactants is typically known or obtainable
from suppliers of branched alcohol feedstocks and described in
commonly owned U.S. patent application Ser. No. 60/680,149 entitled
"Structured Multi-phased Personal Cleansing Compositions Comprising
Branched Anioinic Surfactants", filed on May 12, 2005, by Smith, et
al.
[0031] 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 in a falling film reactor, chlorosulfonic acid
process, sulfuric acid process, or Oleum process.
[0032] 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. 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.
[0033] Amphoteric surfactants are suitable for use in the
multi-phase 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.
[0034] 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 multi-phase, personal cleansing
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] Preferably the nonionic surfactant has an HLB from about 1.0
to about 15.0, preferably from about 3.4 to about 15.0, more
preferably from about 3.4 to about 9.5, even more preferably from
about 3.4 to about 5.0. The multi-phase personal cleansing
composition preferably comprises a nonionic surfactant at
concentrations ranging from about 0.01% to about 50%, more
preferably from about 0.10% to about 10%, and even more preferably
from about 0.5% to about 5.0%, by weight of the surfactant
component.
[0037] 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.
[0038] An electrolyte, if used, can be added per se to the
multi-phase personal cleansing 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.
[0039] Non-Lathering Structured Aqueous Phase: The structured
aqueous phase of the present invention can comprise from about 30%
to about 99%, preferably 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. 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.
[0040] 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.
[0041] 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 cleansing
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 cleansing
composition include cellulose gums and gel, and starches.
Non-limiting examples of associative water structurants for use in
the multi-phase personal cleansing composition include xanthum gum,
gellum gum, pectins, alginates such as propylene glycol alginate,
and mixtures thereof.
[0042] Second, Visually Distinct Phase: 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 may be a benefit phase comprising water in
oil emulsion or an oil in water emulsion. The second visually
distinct phase may comprise a structured surfactant identical to
the structured surfactant or non-lathering structured aqueous phase
in the first visually distinct phase; described in detail
above.
[0043] The benefit phase in the present invention is preferably
anhydrous and can be substantially free of water. The benefit phase
can be substantially free of surfactant. The benefit phase of the
present invention comprises a either a water in oil emulsion or an
oil in water emulsion. In water in oil emulsions, the oil phase is
the continuous phase and the water phase is the discontinuous or
"internal" phase. In oil in water emulsions, the oil phase is the
discontinuous phase and the water phase is the continuous or
"internal" phase. As known in the art, a water in oil and oil in
water emulsions comprises an aqueous phase; an oil; and an
emulsifier.
[0044] The benefit phase of the present invention can comprise from
about 10% to about 99%, more preferably from about 20% to about
95%, more preferably from about 50% to about 90%, and most
preferably from about 60% to about 80% by weight of the benefit
phase, of oil phase.
[0045] The hydrophobic materials suitable for use in the benefit
phase include any natural or synthetic materials with a Vaughan
Solubility Parameter of from about 5 (cal/cm.sup.3).sup.0.5 to
about 15 (cal/cm.sup.3).sup.0.5, some non-limiting examples of such
oils include following: Cyclomethicone 5.92, Squalene 6.03,
Petrolatum 7.33, Isopropyl Palmitate 7.78, Isopropyl Myristate
8.02, Castor Oil 8.90, Cholesterol 9.55, as reported in Solubility
Effects in Product, Package, Penetration and Preservation, C. D.
Vaughan, Cosmetics and Toiletries, Vol. 103, Oct. 1988. Preferably,
the hydrophobic material has an overall solubility parameter of
less than about 12.5 (cal/cm.sup.3).sup.0.5 and preferably less
than 11 (cal/cm.sup.3).sup.0.5. By "overall solubility parameter"
it is meant that one can use materials with higher solubility
parameter blends with other materials with lower solubility
parameters to reduce the overall solubility parameter. For example,
a small portion of diethylene glycol with solubility parameter of
13.61 can be blended with lanolin oil with solubility parameter of
7.3 and a co-solubilizing agent to create a mixture with a
solubility parameter of less than about 12.5
(cal/cm.sup.3).sup.0.5.
[0046] Suitable for use herein are hydrophobic materials that
include, but are not limited to the group consisting of petrolatum,
lanolin, hydrocarbon oils (i.e. mineral oil), natural and synthetic
waxes(i.e micro-crystalline waxes, paraffins, ozokerite, lanolin
wax, lanolin alcohols, lanolin fatty acids, polyethylene,
polybutene, polydecene and perhydrosqualen), volatile or
non-volatile organosiloxanes and oganosiloxane derivatives (i.e.
dimethicones, cyclomethicones, alkyl siloxanes,
polymethylsiloxanes, and methylphenylpolysiloxanes), lanolin oil,
esters (i.e. isopropyl lanolate, acetylated lanolin, acetylated
lanolin alcohols, lanolin alcohol linoleate, lanolin alcohol
riconoleate), natural and synthetic triglycerides (i.e. castor oil,
soy bean oil, sunflower seed oil, maleated soy bean oil, safflower
oil, cotton seed oil, corn oil, walnut oil, peanut oil, olive oil,
cod liver oil, almond oil, avocado oil, palm oil and sesame oil)
and combinations thereof.
[0047] Oil in Water Emulsifier: In embodiments of the benefit phase
which are a oil in water emulsion the emulsifying agent typically
comprise from about 0.1% to about 10%, preferably from about 0.5%
to about 5%, and more preferably from about 0.5% to about 3%, by
weight of the benefit phase, of an emulsifier. Preferred oil in
water emulsifiers are those that reduce the surface tension of
water to not less 60 mN/m at 25.degree. C. as measured by standard
surface tension apparati and methods known to those of ordinary
skill in the art, for example ASTM D1331-89 (2001) Method A,
"Surface Tension". Preferred emulsifiers exhibit a minimum surface
tension in water of 60 mN/m or higher. Suitable emulsifiers promote
stability of the oil in water emulsion by inhibiting coalescence of
the oil droplets, and/or inhibiting phase separation of the oil and
water phases.
[0048] Some suitable oil in water emulsifiers are Pemulen TR-1
(Acrylates/C10-30 Alkyl Acrylate Crosspolymer-Noveon), Pemulen TR-2
(Acrylates/C10-30 Alkyl Acrylate Crosspolymer-Noveon), ETD 2020
(Acrylates/C10-30 Alkyl Acrylate Crosspolymer-Noveon), Carbopol
1382 (Acrylates/C10-30 Alkyl Acrylate Crosspolymer-Noveon),
Natrosol CS Plus 330, 430, Polysurf 67 (Cetyl Hydroxyethyl
Cellulose-Hercules), Aculyn 22 (Acrylates/Steareth-20 Methacrylate
Copolymer-Rohm&Haas) Aculyn 25 (Acrylates/Laureth-25
Methacrylate copolymer-Rohm&Haas), Aculyn 28
(Acrylates/Beheneth-25 Methacrylate copolymer-Rohm&Haas),
Aculyn 46 (Peg-150/Stearyl Alcohol/SMDI copolymer-Rohm&Haas)
Stabylen 30 (Acrylates/Vinyl Isodecanoate-3V), Structure 2001
(Acrylates/Steareth-20 Itaconate copolymer-National Starch),
Structure 3001 (Acrylates/Ceteth-20 Itaconate copolymer-National
Starch), Structure Plus (Acrylates/Aminoacrylates/C10-30 Alkyl Peg
20 Itaconate copolymer-National Starch, Quatrisoft LM-200
(Polyquaternium-24), the metal oxides of titanium, zinc, iron,
zirconium, silicon, manganese, aluminum and cerium, polycarbonates,
polyethers, polyethylenes, polypropylenes, polyvinyl chloride,
polystyrene, polyamides, polyacrylates, cyclodextrins and mixtures
thereof.
[0049] Other suitable emulsifiers include sub-micron organic or
inorganic particles absorbed at the interface. Examples of suitable
particles include micronized zeolite, fumed silica, titanium
dioxide, zinc oxide, and aluminum oxide.
[0050] Water in Oil Emulsifiers: If the benefit phase is a water in
oil emulsion, the benefit phase can comprise 0.1% to about 20%,
more preferably from about 0.1% to about 10%, still more preferably
from about 0.5% to about 9%, by weight of the benefit phase, of one
or more emulsifiers.
[0051] Preferred water in oil emulsifiers of the present invention
are selected from stearic acid, palmitic acid, stearyl alcohol,
cetyl alcohol, behenyl alcohol, stearic acid, palmitic acid, the
polyethylene glycol ether of stearyl alcohol having an average of
about 1 to about 5 ethylene oxide units, the polyethylene glycol
ether of cetyl alcohol having an average of about 1 to about 5
ethylene oxide units, and mixtures thereof. More preferred
emulsifiers of the present invention are selected from stearyl
alcohol, cetyl alcohol, behenyl alcohol, the polyethylene glycol
ether of stearyl alcohol having an average of about 2 ethylene
oxide units (steareth-2), the polyethylene glycol ether of cetyl
alcohol having an average of about 2 ethylene oxide units, and
mixtures thereof. Even more preferred emulsifiers are selected from
PEG-30 Dipolyhydroxystearate, Sorbitan Oleate and mixtures thereof.
When using petrolatum alone or with mineral oil we have found
mixtures of anionic/amphoteric and nonionic surfactants can be used
to make water in oil emulsions. These surfactants include ammonium
lauryl sulfate, ammonium laureth sulfate, sodium lauryl sulfate,
sodium laureth sulfate, sodium tridecyl sulfate, sodium trideceth
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, sodium 3-dodecyl-aminopropionate,
sodium 3-dodecylaminopropane sulfonate, sodium lauryl sarcosinate,
N-alkyltaurines, cocoamidopropyl betaine, 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.
[0052] Density Modifiers: The density modifiers of the present
invention can be comprised in the benefit phase. Just as low
density microspheres can be added to the structured surfactant
component of the present invention to improve stability, high
density materials can be added to the benefit component to increase
its density having the same impact on stability. The high density
particles employed to increase the overall density of the benefit
component are particles having a density greater than 1.1
g/cm.sup.3, preferably greater than 1.5 g/cm.sup.3, more preferably
greater than 2.0 g/cm.sup.3, most preferably greater than 2.5
g/cm.sup.3. The high density particles generally have a diameter
less than 200 .mu.m, preferably less than 100 .mu.m, most
preferably less than 40 .mu.m. Preferably, the high density
particles are selected from water-insoluble inorganic materials,
metals, metal oxides, metal alloys and mixture thereof.
Non-limiting examples include calcium carbonate, silica, clays,
mica, talc, iron, zinc, copper, lead, titanium dioxide, zinc oxide,
and the like.
[0053] The density modifiers can also be added to the fist visually
distinct phase. To further improve stability under stress
conditions such as high temperature and vibration, it is preferable
to adjust the densities of the separate components or phase, such
that they are substantially equal. To achieve this, low density
microspheres can be added to the surfactant component or phase of
the mild, structured, multi-phase cleansing composition. The low
density microspheres employed to reduce the overall density of the
surfactant component are particles having a density lower than 0.7
g/cm.sup.3, preferably less than 0.2 g/cm.sup.3, more preferably
less than 0.1 g/cm.sup.3, most preferably less than 0.05
g/cm.sup.3. The low density microspheres generally have a diameter
less than 200 .mu.m, preferably less than 100 .mu.m, most
preferably less than 40 .mu.m.
[0054] The microspheres are produced from any appropriate inorganic
or organic material, compatible with a use on the skin, that is,
nonirritating and nontoxic. These microspheres may be produced
thermoplastic materials and can be in the dry or hydrated state.
Among hollow microspheres which can be used, special mention may be
made of those marketed under the brand name EXPANCEL.RTM.
(thermoplastic expandable microspheres) by the Akzo Nobel Company,
especially those of DE (dry state) or WE (hydrated state) grade.
Representative microspheres derived from an inorganic material,
include, for instance, "QCEL.RTM. Hollow Microspheres" and
"EXTENDOSPHERES".TM. Ceramic Hollow Spheres", both available from
the PQ Corporation. Examples are: Qcel.RTM. 300; Qcel.RTM. 6019;
Qcel.RTM. 6042S.
[0055] Additional Ingredients: Either phase of the multi-phase
personal cleansing composition, 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%, by weight of the phase, 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. Suitable polymeric phase structurants 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] Either phase of the multi-phase personal cleansing
compositions 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.RTM. R). Preferably, the liquid crystalline
phase inducing structurant is selected from lauric acid,
trihydroxystearin, lauryl pyrrolidone, and tridecanol.
[0057] The multi-phase personal cleansing compositions can further
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 are more fully described 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] Other non limiting examples of these optional ingredients
include vitamins and derivatives thereof (e.g., ascorbic acid,
vitamin E, tocopheryl acetate), sunscreens; thickening agents,
preservatives for maintaining the anti microbial integrity of the
cleansing compositions, anti-acne medicaments, antioxidants, skin
soothing and healing agents (i.e. aloe vera extract, allantoin),
chelators, sequestrants and agents suitable for aesthetic purposes
(i.e. fragrances, essential oils, skin sensates, lightning agents.
pigments, pearlescent agents shiny particles, particles or beads,
exfoliating beads, essential oils) and the like. 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. The
preferred pH range of the structured multi-phase personal cleansing
composition is from about 5 to about 8.
[0059] Method of Use: The mild, multi-phase cleansing 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 structured surfactant component,
hydrophobic benefit 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.
[0060] Method of Manufacture: The multi-phase personal cleansing
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, requiring 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.
[0061] 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. From the combining section the phases are moved into the
blending section and are blended such that the single resulting
product exhibits a distinct pattern of the phases. Next, the
resultant product is pumped by a single nozzle and filing the
container with the resulting product.
[0062] If the multi-phase personal cleansing compositions are
patterned, it can be desirable to be packaged as a personal
cleansing article. The personal cleansing 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.
[0063] Yield Stress and Zero Shear Viscosity Method: 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.
[0064] 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.
[0065] 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.
[0066] 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 on 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
[0067] 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
[0068] 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.
[0069] Ultracentrifugation Method: 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 cleansing 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 cleansing 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.
[0070] First, dispense about 4 grams of multi-phase personal
cleansing 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: 50,000rpm, 18 hours, and 25.degree. C.
[0071] 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
[0072] 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.
[0073] Finally, the structured domain volume ratio is calculated as
follows: Structured Domain Volume Ratio=H.sub.c/H.sub.s *100%. If
there is no benefit phase present, use the total height as the
surfactant layer height, H.sub.s=H.sub.a.
[0074] Lather Volume Test: Lather volume of a cleansing phase, a
structured surfactant component or a structured domain of a
structured multi-phase personal cleansing 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
cleansing 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).
[0075] 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, is
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.
[0076] 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.
[0077] T-Bar Method for Assessing Structured Surfactant Stability
In Presence of Lipid: 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).
[0078] 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.
[0079] 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 6th 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
[0080] 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.
EXAMPLES
[0081] 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 3-5 are examples of the first
visually distinct phase of the present invention. TABLE-US-00001
TABLE 1 First visually distinct phase example Comparative Example 1
2 3 4 5 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-Agualon 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 3 V) 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 -- -- -- -- -- anionic surfactant Branched anionic
surfactant, % of anionic -- -- 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/ 500/
650/ 540/ 510/ Flash/Total (ml/ml) 1810 1930 2340 2150 2020
Structured Domain Volume Ratio 64 52 91 86 88 Stability: % Third
Phase -- 6 -- -- -- T-bar % viscosity change -23 -37 -18 -15 -7
[0082] 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 TABLE 2 Examples of the Present
Invention: Non-Lathering Structured Aqueous Phase and Oil in Water
Emulsion Materials Percent Material in Composition Example #: 6 7 8
9 Water, distilled QS QS QS QS Cetyl hydroxyethyl cellulose
(Natrosol Plus, -- -- 0.7 0.7 Hercules-Aqualon) Acrylates/Vinyl
Isodecanoate Crosspolymer 1.0 0.8 -- -- (Stabylen 30 from 3 V)
Xanthan gum (Keltrol CGT or Keltrol 1000 1.0 0.8 -- -- from Kelco)
DMDM Hydantoin, preservative 0.4 0.4 0.4 0.4 EDTA 0.05 0.04 0.05
0.04 Mineral oil (Hydrobrite 1000, Witco) 0.03 4.82 0.03 21
Petrolatum (Super White Protopet, Witco) 20.0 18.78 70 49
Triethanolamine 0.80 0.80 -- -- Sodium chloride 3.0 2.4 3.0 2.4
Pigment 0.35 0.35 0.35 0.35
[0083] The Examples 6-9 in Table 2 can be prepared by dispersing
polymers in water with high shear, adding salt and remaining
ingredients except petrolatum and mineral oil, 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-00003 TABLE 3
Examples of the Present Invention: Non-Lathering Structured Aqueous
Phase and Water in Oil Emulsion Materials Percent Material in
Composition Example #: 10 11 12 13 14 15 Water, distilled (internal
QS QS QS QS QS QS phase) Glycerin -- -- 30 30 -- -- DMDM Hydantoin,
0.4 0.4 0.4 0.4 0.4 0.4 preservative EDTA 0.05 0.04 0.05 0.04 0.05
0.04 Mineral oil (Hydrobrite 1000, -- 9 -- 9 -- 9 Witco) Petrolatum
(Super White 60 51 60 51 60 51 Protopet, Witco) PEG-30 1 1 1 1 1 1
Dipolyhydroxystearate (Arlacel P135 Uniqema) Sorbitan Oleate (Span
80 3 3 3 3 3 3 Uniqema) Sodium chloride 3.0 2.4 3.0 2.4 3.0 2.4
Pigment 0.35 0.35 0.35 0.35 0.35 0.35 Perfume -- -- -- -- 1.0
1.0
[0084] The Examples 10-15 in Table 3 can be prepared by melting
petrolatum at 80.degree. C. and adding mineral oil, pigment, P135
and Span 80 into a vessel. In a separate vessel heat water to
75.degree. C. and add salt and EDTA. Add water phase slowly to oil
phase with paddle mixing and bring temperature down to 45.degree.
C. continuing to mix. Add preservative and perfume and continue to
mix. TABLE-US-00004 TABLE 4 Examples of the Present Invention:
Non-Lathering Structured Aqueous Phase and Water in Oil Emulsion
Percent Material in Composition Materials 21 22 Water, distilled
(internal phase) QS QS DMDM Hydantoin, preservative 0.4 0.4 EDTA
0.05 0.04 Mineral oil (Hydrobrite 1000, Witco) -- 9 Petrolatum
(Super White Protopet, Witco) 60 51 Any surfactant phase in
examples 3-5 10 10 Sodium chloride 3.0 2.4 Perfume 1.0 1.0 Pigment
0.35 0.35
[0085] The Examples 21-22 in Table 4 can be prepared by melting
petrolatum at 80.degree. C. and add mineral oil and pigment reduce
temperature to 60.degree. C. in a vessel. In a separate vessel, mix
water, one surfactant system, salt and EDTA at room temperature.
Add water phase slowly to oil phase with paddle mixing and bring
temperature down to 45.degree. C. continuing to mix. Add
preservative and perfume and continue to mix.
[0086] 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. 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.
[0087] 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.
[0088] 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.
* * * * *