Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
' CA 02257116 2004-09-30
' ,
WO 97/49381 PCT/EP97100896
ADDTTjVE COMPOSITION FOR DELIVERING BENEFTf AGENT AND CLfiANSING BARS CON-
TAINING SAID ADD>?7V6S
The present invention relates to bar compositions,
particularly synthetic soap bar compositions, able to deliver
beneficial agents (e. g., silicone) in higher amounts than
previously possible. In particular, the invention relates to
additive compositions (e. g., soap chips) comprising a benefit
agent which are then mixed with non-beneficial agent chips
prior to milling, extruding and stamping the bars. The
invention further relates to a method of making the
additives.
It has long been a desirable goal to deliver some kind
of benefit agent (e. g., silicone or other oils) to the skin
through a personal wash composition.
In liquid cleansers, for example, cationic hydrophilic
polymers such as Polymer JR'R' from Amerchol or Jaguar'R' from
l3hQne Poulenc have been used to enhance delivery of benefit
5
agents (EP 93,602; WO 94/03152; and WO 94/03151). In
applicants' International application, WO 96/29979 to Tsuar
et al., separate hydrogel particles as a structure to
entrap the benefit agent in concentrated form.
Delivery of benefit agents (e.g., silicone) in bar
compositions has proven much more difficult for a number of
reasons. If the benefit agent is soluble in any component of
the bar composition, for example, it may simply solubilize
into these components during the batch mixing phase (prior
to cooling and chip formulation) and either no benefit agent
CA 02257116 2004-09-30
a ~ ~
..
WO 97/49381 PCT/EP97/00896
2
or an insufficient amount of benefit agent will be present in
the final bar tafter milling, plodding and extrusion of
chips) to be delivered to the skin. The overly soluble
benefit agent may also reduce viscosity and cause improper
mixing. If the benefit agent is too viscous, on the other
hand, it tends to get in the processing equipment and become
too difficult to process.
U.S. patent No. 5,154,849 to Visscher et al. teaches bar
compositions containing a silicone skin mildness/moisturizing
aid component. In one embodiment, the silicone component may
be mixed with a carrier which is selected to facilitate
incorporation of the silicone. Preferred carrier is said to
be polyethylene glycol. At column 16, the reference
describes that silicone is mixed into melted CarbowaxTM
(polyethylene glycol), that the mixture is cooled to form
.. flakes, and that the flakes are preferably added to an
amalgamator.
It is clear, however, that the Visscher et al. reference
contemplates a silicone/carrier system different from the
benefit agent/carrier/fumed silica system of the subject
invention. First, the Visscher patent does not teach fumed
silica, a critical component of the additive compositions arid
one which is believed to provide the structure required to
retain and engulf the benefit agent (e. g., silicone).
Second, as suggested above and as shown in Figures 1 and 2,
the structure of the carrier/silicone chip is distinct. The
Visscher et al. chip does not contain the silicone in
discrete droplets, but rather the silicone oozes and
surrounds the carrier. By contrast, the benefit agent
droplets of the invention are discrete droplets retained
within the chip. This helps to ensure the silicone does not ,
ooze and interfere with processing.
CA 02257116 1998-11-20
WO 97/49381 PCT/EP97/00896
3
The discrete particles of the invention, in turn, are
present for two reasons, it is believed. The first, as noted
above, is presence of fumed silica which, while not wishing
to be bound by theory, it is believed helps to work with the
carrier (i.e., PEG) to better entrap the silicone. The
second is that, unlike the Visscher et al. system, the
present invention requires there be an equal amount or more
of carrier relative to the benefit agent. By contrast, it
appears from Visscher et al., where eleven pounds of silicone
(column 15, lines 1-2), are mixed with 5 to 6 pounds of
Carbowax (column 15, line 29) that there is probably an
excess of silicone to PEG and, at the least, there is no
recognition of the criticality of having an equal amount or
more of PEG to silicone.
I5
In short, the chips of the Visscher reference are
extremely difficult to process both because there is no
control over the amount of silicone used and because there is
no use of fumed silica.
SUMMARY OF THE INVENTION
Unexpectedly, applicants have found that, when specific
additives are made containing an equal amount or greater of
polyalkylene glycol to benefit agent and further containing
fumed silica, the benefit agent (e. g., silicone) is prepared
in the form of discrete droplets which in turn allow the
benefit agent to be much more readily processed.
Specifically, the invention comprises a chip composition
comprising:
(a) 40o to about 80o by wt. of the chip composition of
a polyalkylene glycol having a molecular weight
greater than about 4,000, preferably 5,000 to
20,000, more preferably 5,000 to 10,000;
CA 02257116 1998-11-20
WO 97149381 PCT/EP97/00896
4
(b) 10o to 40~ by wt. of the chip composition of
benefit agent (e. g., silicone);
(c) 0.010 to 10% by wt. chip composition fumed silica;
(d) 0.0~ to loo by wt. chip composition, preferably 0~
to 5% by wt. water; and
(e) Oo to 15o by wt. chip composition CY to C,l fatty
acid.
In a second embodiment of the invention, the invention
comprises an extruded bar composition produced using about
20o to 40o chips as described above and about 80o to 60%
chips comprising about 5o to 90o by wt. of a surfactant
system wherein the surfactant is selected from the group
consisting of soap, anionic surfactant, nonionic surfactant,
amphoteric surfactant, zwitterionic surfactant, cationic
surfactant and mixtures thereof. The "soap and/or
surfactant" chips additionally may comprise other components
typically found in such chips such as, for example, minor
amounts of fragrance, preservative (e. g., butylated hydroxy
toluene) skin feel polymer (e. g., guar) etc.
Although the surfactant system of the second (non-
additive containing) chip may be a pure soap surfactant
system, preferably the surfactant system comprises:
(a) a first synthetic surfactant which is an anionic
surfactant; and
(b) a second synthetic surfactant selected from the
group consisting of a second anionic different from
the first, a nonionic, an amphoteric and mixtures
thereof.
A particularly preferred surfactant system comprises
acyl isethionate as the first anionic and a sulfosuccinate or
a betaine surfactant or mixtures of the two.
CA 02257116 1998-11-20
WO 97/49381 PCT/EP97/00896
In a third embodiment of the invention, the invention
comprises a method of making benefit agent containing chips
comprising:
(a) 40o to 80o polyalkylene glycol;
5 (b) 10a to 40~ benefit agent;
(c) 0.01% to 10o fumed silica;
(d) 0 % to 10 % water; and
(e) 0 o to 10 o CB to C22 fatty acid; which method
comprises mixing the ingredients at temperatures above the
melting point of polyalkylene glycol (i.e., above about 50°C)
for 1 to 60 minutes; cooling on a chill roll (at about 0° to
25°C); and collecting.
BRIEF DESCRIPTION OF FI RES
Figure 1 is a micrograph of a chip produced following
process described in U.S. patent No. 5,154,849 to visscher et
al. wherein the chip is flooded with water and photographed
under a microscope. The silicone does not form discrete
particles but forms a large layer of silicone surrounding the
polyalkylene glycol. The viscous silicone gets caught in
machinery and inhibits processing.
Figure 2 is a micrograph of a chip product according to
the subject invention. As noted, the benefit agent is found
in discrete drops. Further, it is obvious, there is far less
benefit agent present (e. g., to interfere with processing)
than in Figure 1.
DETAILED DESCRIPTION OF THE INVENTION
In one embodiment of the invention, the present
invention relates to novel soap chip compositions (e.g., in
the process for making bars, molten compositions are formed
which are then cooled on what is commonly called a chill roll
CA 02257116 2004-09-20
C6353
6
to form flakes or chips; these chips are subsequently refined
and/or plodded to form billets which are stamped and cut to
form final bars) which are readily processable in
conventional soap machinery while still showing significant
benefit agent deposition (i.e., comparable to deposition
obtained in liquid body washes).
As seen from Figures 1 and 2, by carefully controlling
the level of benefit agent (so that it cannot exceed the
level of alkylene glycol carrier) and by utilizing fumed
silica (while not wishing to be bound by theory, it is
believed the fumed silica forms three dimensional networks,
altering flow properties of, for example, silicone, and
causes thickening), applicants have been able to provide
r 15 discrete droplets of benefit agent so that the agent is
unable to stick to the machinery and significantly inhibits
processing.
CHIP COMPOSITION
Polvalylene Glvcol
The first component of the chip composition is the
polyalkylene glycol carrier. This carrier should comprise
about 40o to 80% by wt., preferably about 50o to 70o by wt.
of the chip composition. Preferably, the polyalkylene glycol
should have a molecular weight greater than 4,000 to about
100,000, preferably 4,000 to 10,000. Especially preferred
carriers are polyethylene glycol and propylene glycol, for
example Carbowax PEG 8000~R~ from Union Carbide.
Benefit Aaent
The benefit agent "composition" of the subject invention
may be a single benefit agent component or it may be a
CA 02257116 1998-11-20
WO 97/49381 PCT/EP97/00896
7
benefit agent compound added via a carrier. Further the
benefit agent composition may be a mixture of two or more
compounds one or all of which may have a beneficial aspect.
In addition, the benefit agent itself may act as a carrier
for other components one may wish to add to the bar
composition.
The benefit agent can be an "emollient oil" by which is
meant a substance which softens the skin (stratum corneum) by
increasing into water content and keeping it soft by
retarding decrease of water content.
Preferred
emollients
include:
(a) silicone oils, gums and modifications thereof such
as linear and cyclic polydimethylsiloxanes; amino,
alkyl alkylaryl and aryl silicone oils;
(b) fats and oils including natural fats and oils such
as jojoba, soybean, rice bran, avocado, almond,
olive, sesame, persic, castor, coconut, mink oils;
cacao fat; beef tallow, lard; hardened oils
obtained by hydrogenating the aforementioned oils;
and synthetic mono, di and triglycerides such as
myristic acid glyceride and 2-ethylhexanoic acid
glyceride;
(c) waxes such as carnauba, spermaceti, beeswax,
lanolin and derivatives thereof;
(d) hydrophobic plant extracts;
(e) hydrocarbons such as liquid paraffins, vaseline,
microcrystalline wax, ceresin, squalene, pristan
and mineral oil;
(f) higher fatty acids such as lauric, myristic,
palmitic, stearic, behenic, oleic, linoleic,
linolenic, lanolic, isostearic and poly unsaturated
fatty acids (PUFA);
(g) higher alcohols such as lauryl, cetyl, stearyl,
CA 02257116 1998-11-20
WO 97/49381 PCT/EP97/00896
8
oleyl, behenyl, cholesterol and 2-hexydecanol
alcohol;
(h) esters such as cetyl octanoate, myristyl lactate,
cetyl lactate, isopropyl myristate, myristyl
myristate, isopropyl palmitate, isopropyl adipate,
butyl stearate, decyl oleate, cholesterol
isostearate, glycerol monostearate, glycerol
distearate, glycerol tristearate, alkyl lactate,
alkyl citrate and alkyl tartrate;
(i) essential oils such as mentha, jasmine, camphor,
white cedar, bitter orange peel, ryu, turpentine,
cinnamon, bergamot, citrus unshiu, calamus, pine,
lavender, bay, clove, hiba, eucalyptus, lemon,
starflower, thyme, peppermint, rose, sage, menthol,
cineole, eugenol, citral, citronelle, borneol,
linalool, geraniol, evening primrose, camphor,
thymol, spirantol, penene, limonene and terpenoid
oils:
(j) lipids such as cholesterol, ceramides, sucrose
esters and pseudo-ceramides as described in
European Patent Specification No. 556,957;
(k) vitamins such as vitamin A and E, and vitamin alkyl
esters, including those vitamin C alkyl esters;
(1) sunscreens such as octyl methoxyl cinnamate (Parsol
MCX) and butyl methoxy benzoylmethane (Parsol
1789):
(m) phospholipids; and
(n) mixtures of any of the foregoing components.
A particularly preferred benefit agent is silicone,
preferably silicones having viscosity greater than about
10,000 centipoise. The silicone may be a gum and/or it may
be a mixture of silicones. One example is
polydimethylsiloxane having viscosity of about 60,000
centistokes.
CA 02257116 1998-11-20
WO 97/49381 PCT/EP97/00896
9
The benefit agent generally comprises about 10% to 40~,
preferably 20o to 400, most preferably 25o to 40o by weight
of the chip composition.
Fumed Silica
15
Fumed silica is generally produced by the hydrolysis of
silicon tetrachloride vapor in a flame of hydrogen and
oxygen. The process produces particles of from about 7 to 30
millimicrons.
The enormous surface area and chain forming abilities
are believed to allow it to form three-demential networks,
altering flowing properties i.e, cause thickening.
Fumed silica will generally comprise the 0.01 to 10o by
wt. of the composition, preferably 1o to 7o by wt., most
preferably 1o to 5o by wt. of the composition.
Other Comr~onents
Water comprises 0 to 100, preferably Oo to 8% by wt.,
most preferably 0.1 to 5o by wt. of the chip composition. It
is sometimes preferred to have little or no additional water
(other than that inherently present in the compounds) in the
chip mixture because this may sometimes cause processing
difficulties.
In addition the chip composition may comprise Oo to 150,
preferably 2o to loo fatty acid, i.e., Ceto C,= fatty acid.
Generally, this is a straight chain, saturated fatty acid
although this is not necessarily the case. The fatty acid
helps to modify the wear rate of the emollient chip to better
match that of the base soap.
CA 02257116 1998-11-20
WO 97/49381 PCT/EP97/00896
BAR COMPOSITIONS
In a second embodiment of the invention, the invention
comprises extruded bar compositions in which 20o to about 400
5 of the chips used to make the final bars comprise the benefit
agent additives (i.e. chips) described above and in which 80%
to 60~ of the chips comprise chips which comprise the
surfactant system defining the final bar.
10 Specifically, the surfactant system chips comprise about
5o to 90o by wt. of a surfactant system wherein the
surfactant is selected from the group consisting of soap
(pure soap surfactant systems are included), anionic
surfactant, nonionic surfactant, amphoteric zwitterionic
surfactant, cationic surfactant and mixtures thereof. These
chips may additionally comprise other components typically
found in final bar compositions, for example, minor amounts
of fragrance, preservative, skin feel polymer etc.
surfactant Svstem
The term "soap" is used herein in its popular sense,
i.e., the alkali metal or alkanol ammonium salts of aliphatic
alkane- or alkene monocarboxylic acids. Sodium, potassium,
mono-, di- and tri-ethanol ammonium cations, or combinations
thereof, are suitable for purposes of this invention. In
general, sodium soaps are used in the compositions of this
invention, but from about to to about 250 of the soap may be
potassium soaps. The soaps useful herein are the well known
alkali metal salts of natural of synthetic aliphatic
(alkanoic or alkenoic) acids having about 12 to 22 carbon
atoms, preferably about 12 to about 18 carbon atoms. They
may be described as alkali metal carboxylates of acrylic
hydrocarbons having about 12 to about 22 carbon atoms.
CA 02257116 1998-11-20
WO 97/49381 PCT/EP97/00896
11
Soaps having the fatty acid distribution of coconut oil
may provide the lower end of the broad molecular weight
range. Those soaps having the fatty acid distribution of
peanut or rapeseed oil, or their hydrogenated derivatives,
may provide the upper end of the broad molecular weight
range.
It is preferred to use soaps having the fatty acid
distribution of coconut oil or tallow, or mixtures thereof,
since these are among the more readily available fats. The
proportion of fatty acids having at least 12 carbon atoms in
coconut oil soap is about 850. This proportion will be
greater when mixtures of coconut oil and fats such as tallow,
palm oil, or non-tropical nut oils or fats are used, wherein
the principle chain lengths are C16 and higher. Preferred
soap for use in the compositions of this invention has at
least about 85g fatty acids having about 12 to 18 carbon
atoms.
Coconut oil employed for the soap may be substituted in
whole or in part by other "high-alluric" oils, that is, oils
or fats wherein at least 500 of the total fatty acids are
composed of lauric or myristic acids and mixtures thereof.
These oils are generally exemplified by the tropical nut oils
of the coconut oil class. For instance, they include: palm
kernel oil, babassu oil, ouricuri oil, tucum oil, cohune nut
oil, murumuru oil, jaboty kernel oil, khakan kernel oil, dika
nut oil, and ucuhuba butter.
A preferred soap is a mixture of about 15o to about 200
coconut oil and about 80e to about 85o tallow. These
mixtures contain about 95o fatty acids having about 12 to
about 18 carbon atoms. The soap may be prepared from coconut
oil, in which case the fatty acid content is about 850 of C1~-
C18 chain length.
CA 02257116 1998-11-20
WO 97/49381 PCT/EP97/00896
12
The soaps may contain unsaturation in accordance with
commercially acceptable standards. Excessive unsaturation is
normally avoided.
Soaps may be made by the classic kettle boiling process
or modern continuous soap manufacturing processes wherein
natural fats and oils such as tallow or coconut oil or their
equivalents are saponified with an alkali metal hydroxide
using procedures well known to those skilled in the art.
Alternatively, the soaps may be made by neutralizing fatty
acids, such as lauric (C12) , myristic (C,4) , palmitic (C,6) , or
stearic (C18) acids with an alkali metal hydroxide or
carbonate.
The anionic detergent active which may be used may be
aliphatic sulfonates, such as a primary alkane (e. g., C8-C22)
sulfonate, primary alkane (e.g., CB-C22) disulfonate, C8-CZa
alkene sulfonate, C8-C22 hydroxyalkane sulfonate or alkyl
glyceryl ether sulfonate (AGS); or aromatic sulfonates such
as alkyl benzene sulfonate.
The anionic may also be an alkyl sulfate (e.g., C1,-C18
alkyl sulfate) or alkyl ether sulfate (including alkyl
glyceryl ether sulfates). among the alkyl ether sulfates are
those having the formula:
RO ( CHZCH20 ) "S03M
wherein R is an alkyl or alkenyl having 8 to 18 carbons,
preferably 12 to 18 carbons, n has an average value of
greater than 1.0, preferably greater than 3; and M is a
solubilizing ration such as sodium, potassium, ammonium or
substituted ammonium. Ammonium and sodium lauryl ether
sulfates are preferred.
CA 02257116 1998-11-20
WO 97149381 PCT/EP97/00896
13
The anionic may also be alkyl sulfosuccinates (including
mono- and dialkyl, e.g., C6-C22 sulfosuccinates); alkyl and
acyl taurates, alkyl and acyl sarcosinates, sulfoacetates,
C8-Cz2 alkyl phosphates and phosphates, alkyl phosphate esters
and alkoxyl alkyl phosphate esters, acyl lactates, Ce-C2~
monoalkyl succinates and maleates, sulphoacetates, alkyl
glucosides and acyl isethionates.
Sulfosuccinates may be monoalkyl sulfosuccinates having
the formula:
R40ZCCH2CH ( S03M) COZM; and
amide-MEA sulfosuccinates of the formula;
R'CONHCHZCH202CCH2CH ( S03M ) C02M
wherein R4 ranges from Ce-C22 alkyl and M is a
solubilizing cation.
Sarcosinates are generally indicated by the formula:
R' CON ( CH3 ) CH~C02M,
wherein R1 ranges from Ce-C2o alkyl and M is a
solubilizing cation.
Taurates are generally identified by formula:
RZCONR3CHzCHzSOjM
wherein Rz ranges from Ce-Czo alkyl, R' ranges from C1-C9
alkyl and M is a solubilizing cation.
Particularly preferred are the Cg-Clp acyl isethionates.
CA 02257116 1998-11-20
WO 97/49381 PCT/EP97/00896
14
These esters are prepared by reaction between alkali metal
isethionate with mixed aliphatic fatty acids having from 6 to
18 carbon atoms and an iodine value of less than 20. At
least 75~ of the mixed fatty acids have from 12 to 18 carbon
atoms and up to 25o have from 6 to 10 carbon atoms.
Acyl isethionates, when present, will generally range
from about 10~ to about 70~ by weight of the total bar
composition. Preferably, this component is present from
about 30o to about 600.
The acyl isethionate may be an alkoxylated isethionate
such as is described in Ilardi et al., U.S. Patent No.
5,393,466, hereby incorporated by reference. This compound
has the general formula:
O X Y
R C-O-CH-CHZ- (OCH-CHZ ) m-S03M'
wherein R is an alkyl group having 8 to 18 carbons, m is
an integer from 1 to 4, X and Y are hydrogen or an alkyl
group having 1 to 4 carbons and M' is a monovalent cation
such as, for example, sodium, potassium or ammonium.
Amphoteric detergents which may be used in this
invention include at least one acid group. This may be a
carboxylic or a sulphonic acid group. They include
quaternary nitrogen and therefore are quaternary amido acids.
They should generally include an alkyl or alkenyl group of 7
to 18 carbon atoms. They will usually comply with an overall
structural formula:
CA 02257116 1998-11-20
WO 97149381 PCT/EP97100896
O R2
R1- [ -C-NH ( CHz ) ~- ] ~-N'-X-Y
5 Rs
where R1 is alkyl or alkenyl of 7 to 18 carbon atoms;
R2 and R3 are each independently alkyl, hydroxyalkyl or
10 carboxyalkyl of 1 to 3 carbon atoms;
m is 2 to 4;
n is 0 to 1;
X is alkylene of 1 to 3 carbon atoms optionally
substituted with hydroxyl, and
Y is -COZ- or -S03-
Suitable amphoteric detergents within the above general
formula include simple betaines of formula:
R2
Rl N'~HzC02_
R3
and amido betaines of formula:
Rz
R1 - CONH ( CHZ ) ~-N'-CHzC02-
Rs
CA 02257116 1998-11-20
WO 97149381 PCT/EP97/00896
16
where n is 2 or 3.
In both formulae R1 , Rz and R3 are as defined
previously. R1 may in particular be a mixture of Clz and C1q
alkyl groups derived from coconut so that at least half,
preferably at least three quarters of the groups R1 have 10
to 14 carbon atoms. R2 and R3 are preferably methyl.
A further possibility is that the amphoteric detergent
is a sulphobetaine of formula:
Rz
Ri-N+- ( CHz ) 3SO3-
R3
or
R2
R1 - CONH ( CHz ) m-N+- ( CHz ) 3503_
R3
where m is 2 or 3, or variants of these in which -(CHz)3
S03- is replaced by
OH
3 0 -CH2CHCHZS03-
In these formulae R1, Rz and R3 are as discussed
previously.
, CA 02257116 2004-09-30
' , v
WO 97/49381 ~ PCTIEP97100896
17
The nonionic which may be used as the second component
of the invention include in particular the reaction products
of compounds having a hydrophobic group and a reactive
hydrogen atom, for example aliphatic alcohols, acids, amides
or alkylphenols with alkylene oxides, especially ethylene
oxide either alone or with propylene oxide. Specific
nonionic detergent compounds are alkyl (C6-Cz~) phenols
ethylene oxide condensates, the condensation products of
aliphatic (CB-C18) primary or secondary linear or branched
alcohols with ethylene oxide, and products made by
condensation of ethylene oxide with the reaction products of
propylene oxide and ethylenediamine. Other so-called
nonionic detergent COnipounds include long chain tertiary
amine oxides, long chain tertiary phosphine oxides and
dialkyl sulphoxides.
The nonionic_ may__ also be._a _ sugar amide, such as a
polysaccharide amide. Specifically, the surfactant may be
one of the lactobionamides described in U.S. Patent No.
5,389,279 to Au et al. or it may be one of the sugar amides
described in Patent No. 5,009,814 to Kelkenberg.
Examples of cationic detergents are the quaternary
amanonium compounds such as alkyldimethylammonium halogenides.
Other surfactants which may be used are described in
U.S. Patent No. 3,723,325 to Parran Jr. and Surface Active
Agents and Detergents~ (Vol. I ~ II) by Schwartz, Perry &
Berch.
Although the bar may be a pure soap bar, preferably the
surfactant system of this chip (forming the surfactant system
CA 02257116 1998-11-20
WO 97/49381 PCT/EP97/00896
18
in the bar) comprises:
(a) a first synthetic surfactant which is anionic; and
(b) a second synthetic surfactant selected from the
group consisting of a second anionic different from
the first, a nonionic, an amphoteric and mixtures
thereof.
The first anionic can be any of those recited above, but
is preferably a Cg to C18 isethionate as discussed above.
Preferably acyl isethionate will comprise 10o to 90o by wt.
total bar composition.
The second surfactant is preferably a sulfosuccinate, a
betaine or mixtures of the two. The second surfactant or
mixture of surfactant will generally comprise 1o to 10o total
bar composition. A particularly preferred composition
comprises enough sulfosuccinate to form 3-8o total bar
compositions and enough betaine to form 1-50 of total bar
composition.
Processina
In general, the additive, benefit agent chips are formed
by mixing the ingredients in a mixer at a temperature just
above the melting point of the polyalkylene glycol (e. g.,
about 50°C and above, generally no higher than about 110°C)
for about 1 to 60 minutes, and then cooling in a chill roll.
Order of addition is not critical. The "non" benefit agent
chips are formed by similarly mixing and cooling.
The chips are than combined, for example, in a hopper
or ribbon mixer where they may be refined (e. g., worked into
a more pliable mass), plodded into billets, stamped and cut.
CA 02257116 2004-09-20
WO 97/49381 PCTIEP971t10896
19
In a third embodiment of the invention, the invention
relates to a method of forming additives tchips) containing a
benefit agent which method comprises:
(a) mixing polyalkylene glycol, benefit agent, fumed
silica, optional water and optional fatty acid in a
container for 1 to 60 minutes at about above 50°C;
and
(b) cooling the mixture on a chill roll to about 0 to
25°C to form chips.
The following examples are intended to further
illustrate the invention and are not intended to limit the
invention in any way.
Unless stated otherwise, all percentages are intended to
be percentages by weight.
EXAMPLF,~
,protocol
Silicone measurement was conducted as follows:
Analysis is done by method known as ICP (Inductively
~5 Coupled Argon Plasma). This procedure required a step
involving extraction with xylene, and is therefore currently
used only in-vitro. The ICP technique employed a Thermo
Jarrell Ash AtomTM Scan 25 with measurements being made at
251.612 nm. Additional ICP measurement parameters are given
below.
The treatment process was as follows:
The porcine skin was shaved, dermatomed, and sectioned
into 25 cm pieces prior to treatment. The skin sample was
CA 02257116 1998-11-20
WO 97/49381 PCT/EP97/00896
then treated by rubbing the bar sample across the skin 10
times, in a back and forth motion. The resulting liquor on
the skin was lathered for 30 seconds and then rinsed for 10
seconds with water which was regulated at 90-95°F. The
5 treated skin sample was placed in a borosilicate
scintillation vial that contained 10 ml of xylene. The
samples were placed on a platform shaker for 1 hour to allow
for the extraction of the silicone. After the extraction
period, the skin was removed from the vial and the extract
10 was analyzed using ICP technique. Sample solutions were
tested against a 10 pm silicone standard.
~~~ical ICP Measurement Parameters for Measurincr Silicone in
Xylene
Torch gas flow high
Auxiliary gas flow 1.5 L/min
Analyzer pump rate 0.9 m L/min
Nebulizer pressure 21 psi
Observation height 12 mm above load cell
Plasma power 1750 W
Wavelength 251.612 nm
Slit height 6 mm
Integration time 4 sec
Example 1
Using the protocol discussed above, benefit agent
deposition (e.g., deposition of silicone) was measured in
compositions representing (1) the bar of Visscher et al. with
no fumed silica chips; (2) the bars of the invention which
did contain fumed silica chips; and (3) a liquid body wash
composition. Each is discussed in greater detail below:
CA 02257116 1998-11-20
WO 97/49381 PCT/EP97/00896
21
(1) ~i.~her Bar (WO 92/08444)
The Visscher bar was obtained following the procedure
taken from WO 92/08444 (equivalent to U.S. Patent No.
5,154,849) where polyethylene glycol is used as a carrier for
silicone in bars (procedure was done in a Patterson mixture).
Procedure was as follows:
(a) 681 gm of Carbowax PEG 8000 was melted and held
around 60°C;
(b) 400 gm of GE 350 cps silicone was added; and
(c) 273 gm of GE 500,000 cps silicone was added.
(The patent explains the carrier to be 10:9 silicone
A:PEG where silicone A is a blend of 40:60 silicone gum,
500,000 cps to silicone fluid, 350 cps)
The mixture remained in the mixer for 45 minutes until
it was considered homogenous. The mixture was then removed
and placed on a chill roll set at 7°C. The resulting "chips"
were soft, pliable and severely tacky. Silicone covered the
entire surface of the equipment.
A sample bar was prepared by chip mixing surfactant
chip: Visscher chip ratio of 4:1 (wherein surfactant chip
comprises 40-60% fatty acid isethionate, 20-30o fatty acid,
1-loo sodium isethionate, 1-10o sulfosuccinate, about 50
betaine, preservatives, dyes and minors); and extruding into
a billet with a Weber Selander plodder. The resulting billet
was soft and from experience not considered a viable product.
The pressed bar lathered poorly. From experience this type
of "chip" cannot be produced using conventional equipment.
More specifically, mixing surfactant chips and Visscher
chips at a weight ratio of 4:1, respectively, resulted in
CA 02257116 1998-11-20
WO 97!49381 PCT/EP97/00896
22
large, non-free flowing clumps which adhered together by
surface silicone. This result impeded feeding into the
extruder. Material which did feed was extruded as a soft,
sticky billet. When stamped, the bar had a poor surface, was
tacky and produced little lather when wetted.
(2) Rar of the Invention
The bar of the invention comprised a 700/300 mixture of
chips wherein the 300 additive chip component had the
following formulation range:
40-100%, preferably 40-800 polyethyleneglycol (e.g. PEG
8000);
10-500, preferably 10-40% polydimethyl siloxane of
60,000 centistokes;
0.1 to 10%, preferably 1 to 5o Cab-o-sil'F' fumed silica
(e.g., fumed silica 45-5);
0-200, preferably 1-100 deionized water; and
0-20g, preferably 0-10a to CB to CZl fatty acid
and
the 700 surfactant chips were like the surfactant chips
used in the Visscher et al. bar, as follows:
about 40-600 by wt. fatty acid isethionate;
about 20-300 by wt. fatty acid;
about 1-100 by wt. sodium isethionate
about 1-100 by wt. sulfosuccinate;
about 5o by wt. betaine; and
remainder preservative, dyes, water and other minors.
A preferred benefit agent chip comprises as follows:
(a) 55-650 PEG
(b) 25-400 silicone
(c) 1-7o silica; and
(d) 0-8o deionized water.
CA 02257116 1998-11-20
WO 97/49381 PCT/EP97/00896
23
The chips were mixed, plodded together at the above-
identified ratios, and extruded into bars.
(3) Liauid Body Wash
The liquid body wash had the following formulation:
o by wt.
Betaine 5-150
Sodium Cocoyl 1-100
Isethionate
Anionic 1-50
Fragrance, preservatives 0.1-2.Oo
Water to balance
As noted deposition results were taken using the ICP
techniques discussed and results set forth as follows:
Deposition.
Visscher Bar 2.16 +/- 0.48 ug/cmv
Bar of Invention 2.24+/- 0.83 ug/cm~
Liquid 2.14 +/- 0.62 ug/cm-
It is surprising that the bar can deposit as well as the
liquids. Moreover, in contrast to Visscher, the bar of the
invention was readily processable and did not clog machinery
(See Example 2).
Examnl 2
To further show differences between the bar of the
invention and bars of Visscher, applicants decided to analyze
the chips more closely.
CA 02257116 1998-11-20
WO 97/49381 PCT/EP97l00896
24
Chips used in formation of the Visscher et al. bar, and
chips carrying benefit agent and used in the formation of the
bars of the invention were micrographed.
As seen from Figures 1 and 2, the Visscher et al. (P&G)
chips show large "blobs" of silicone surrounding the alkylene
glycol while the chips of the invention show small discrete
droplets of silicone.
While not wishing to be bound by theory, it is believed
the difference in amount of silicone and how it is formed
accounts for the tremendous processing difficulties experienced
in forming the P&G bars relative to those of the invention. As
noted above, 4:1 ratio of Visscher chips to surfactant chips
formed large non-free flowing clumps which hindered chip
feeding into the extruder and noodle processing. The clumps
also caused agglomeration in the vacuum chamber which
significantly reduced billet formation. Further, as noted,
material which did extrude was soft and sticky and, when
stamped, the bar had a poor surface, was tacky and produced
little lather when wetted.
