U.S. patent application number 10/627541 was filed with the patent office on 2004-01-29 for emulsifier-free finely dispersed systems of the oil-in-water and water-in-oil type.
Invention is credited to Gers-Barlag, Heinrich, Muller, Anja.
Application Number | 20040018222 10/627541 |
Document ID | / |
Family ID | 7876170 |
Filed Date | 2004-01-29 |
United States Patent
Application |
20040018222 |
Kind Code |
A1 |
Gers-Barlag, Heinrich ; et
al. |
January 29, 2004 |
Emulsifier-free finely dispersed systems of the oil-in-water and
water-in-oil type
Abstract
Cosmetic or dermatological preparations, which are finely
dispersed systems of the oil-in-water or water-in-oil type,
comprising 1. an oil phase, 2. an aqueous phase, 3. at least one
modified polysaccharide which (a) has both hydrophilic and
lipophilic properties, i.e. has amphiphilic character, and is thus
dispersible both in water and in oil,and which (b) has no
thickening properties, and 4. at most 0.5% by weight of one or more
emulsifiers. and also optionally comprising further cosmetic or
pharmaceutical auxiliaries, additives and/or active substances.
Inventors: |
Gers-Barlag, Heinrich;
(Kummerfeld, DE) ; Muller, Anja; (Rumpel,
DE) |
Correspondence
Address: |
KURT BRISCOE
NORRIS, MCLAUGHLIN & MARCUS, P.A.
220 EAST 42ND STREET, 30TH FLOOR
NEW YORK
NY
10017
US
|
Family ID: |
7876170 |
Appl. No.: |
10/627541 |
Filed: |
July 25, 2003 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10627541 |
Jul 25, 2003 |
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09744496 |
Jan 24, 2001 |
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09744496 |
Jan 24, 2001 |
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PCT/EP99/05241 |
Aug 1, 1998 |
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Current U.S.
Class: |
424/401 ;
424/70.13; 514/60 |
Current CPC
Class: |
A61K 2800/654 20130101;
A61K 8/0241 20130101; Y10S 514/937 20130101; Y10S 514/859 20130101;
A61K 8/732 20130101; Y10S 514/938 20130101; Y10S 514/844 20130101;
Y10S 514/848 20130101; A61Q 17/04 20130101; A61K 2800/33 20130101;
A61K 8/06 20130101; A61Q 19/00 20130101; A61K 2800/412
20130101 |
Class at
Publication: |
424/401 ; 514/60;
424/70.13 |
International
Class: |
A61K 031/715; A61K
007/06; A61K 007/11 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 1, 1998 |
DE |
198 34 821.5 |
Claims
1. Cosmetic or dermatological preparations, which are finely
dispersed systems of the oil-in-water or water-in-oil type,
comprising 1. an oil phase, 2. an aqueous phase, 3. at least one
modified polysaccharide which (a) has both hydrophilic and
lipophilic properties, i.e. has amphiphilic character, and is thus
dispersible both in water and in oil,and which (b) has no
thickening properties, and 4. at most 0.5% by weight of one or more
emulsifiers.
2. Preparations according to claim 1, characterized in that they
are emulsifier-free.
3. Preparations according to one of the preceding claims,
characterized in that further cosmetic or pharmaceutical
auxiliaries, additives and/or active ingredients are present.
4. Preparations according to one of the preceding claims,
characterized in that they are free from hydrocolloids,
particularly advantageously free from carbomers or carbopols.
5. Preparations according to one of the preceding claims,
characterized in that the content of one or more modified
polysaccharides is between 0.1% by weight and 30% by weight, based
on the total weight of the preparations.
6. Preparations according to one of the preceding claims,
characterized in that the average particle diameter of the modified
polysaccharides used is less than 20 .mu.m, particularly
advantageously less than 15 .mu.m.
7. Preparations according to one of the preceding claims,
characterized in that the modified polysaccharide(s) is/are chosen
from the group of starch ethers and starch esters.
8. Preparations according to one of the preceding claims,
characterized in that, in addition to modified polysaccharides,
further amphiphilic pigments are present, in particular boron
nitride and/or microfine polymer particles and/or micronized,
inorganic pigments which are chosen from the group of amphiphilic
metal oxides, in particular from the group consisting of titanium
dioxide, zinc oxide, iron oxides or iron mixed oxides, silicon
dioxide or silicates, it being possible for these pigments to be
present either individually or else as a mixture.
9. Preparations according to one of the preceding claims,
comprising one or more additives or active substances selected from
the group consisting of antioxidants and/or UV protectants.
10. Preparations according to one of the preceding claims,
comprising one or more additives or active substances selected from
the group consisting of astringents and/or antimicrobially
effective substances and/or substances effective against acne.
Description
[0001] The present invention relates to emulsifier-free finely
dispersed systems of the oil-in-water and water-in-oil type,
preferably as cosmetic or dermatological preparations.
[0002] Emulsions are generally taken to mean heterogeneous systems
which consist of two liquids which are immiscible or have only
limited miscibility with one another, which are usually referred to
as phases. In an emulsion, one of the two liquids is dispersed in
the form of very fine droplets in the other liquid.
[0003] If the two liquids are water and oil and if oil droplets are
finely dispersed in water, then this is an oil-in-water emulsion
(O/W emulsion, e.g. milk). The basic character of a ONV emulsion is
defined by the water. In a water-in-oil emulsion (W/O emulsion,
e.g. butter), the principle is reversed, the base character here
being determined by the oil.
[0004] In order to achieve permanent dispersion of one liquid in
another, emulsions in the traditional sense require the addition of
an interface-active substance (emulsifier). Emulsifiers have an
amphiphilic molecular structure, consisting of a polar
(hydrophilic) and a nonpolar (lipophilic) molecular moiety, which
are spatially separate from one another. In simple emulsions,
finely dispersed droplets of one phase, surrounded by an emulsifier
shell, (water droplets in W/O emulsions or lipid vesicles in O/W
emulsions) are present in the second phase. Emulsifiers lower the
interfacial tension between the phases by positioning themselves at
the interface between the two liquids. At the phase boundary, they
form oil/water interfacial films, which prevent irreversible
coalescence of the droplets. Emulsions are frequently stabilized
using emulsifier mixtures.
[0005] Traditional emulsifiers can, depending on their hydrophilic
molecular moiety, be divided into ionic (anionic, cationic and
amphoteric) and nonionic:
[0006] The most well known example of an anionic emulsifier is
soap, which is usually the term used for the water-soluble sodium
salts or potassium salts of saturated or unsaturated higher fatty
acids.
[0007] Important examples of cationic emulsifiers are quatemary
ammonium compounds.
[0008] The hydrophilic molecular moiety of nonionic emulsifiers
frequently consists of glycerol, polyglycerol, sorbitans,
carbohydrates and polyoxyethylene glycols, and, in most cases, is
linked to the lipophilic molecular moiety via ester and ether
bonds. The lipophilic molecular moiety usually consists of fatty
alcohols, fatty acids or isofatty acids.
[0009] By varying the structure and the size of the polar and
nonpolar molecular moiety, the lipophilicity and hydrophilicity of
the emulsifiers can be varied within wide limits.
[0010] A decisive factor for the stability of an emulsion is the
correct choice of emulsifiers. The characteristics of all
substances present in the system are to be taken into
consideration. In the case of, for example, skin care emulsions,
polar oil components and, for example, UV filters lead to
instability. As well as the emulsifiers, therefore, other
stabilizers are also used which, for example, increase the
viscosity of the emulsion and/or act as a protective colloid.
[0011] Emulsions are an important type of product in the field of
cosmetic and/or dermatological preparations.
[0012] Cosmetic preparations are essentially used for skin care.
The main aim of skin care in the cosmetics sense is to strengthen
or rebuild the skin's natural function as a barrier against
environmental influences (e.g. dirt, chemicals, microorganisms) and
against the loss of endogenous substances (e.g. water, natural
fats, electrolytes). If this function becomes impaired, increased
resorption of toxic or allergenic substances or infection by
microorganisms may result, leading to toxic or allergic skin
reactions.
[0013] Another aim of skin care is to compensate for the loss by
the skin of grease and water caused by daily washing. This is
particularly important if the natural regeneration ability is
inadequate. Furthermore, skin care products should protect against
environmental influences, in particular against sun and wind, and
delay skin ageing.
[0014] Cosmetic preparations are also used as deodorants. Such
formulations are used to control body odour which is produced when
fresh sweat, which is in itself odourless, is decomposed by
microorganisms.
[0015] Medicinal topical compositions usually comprise one or more
medicaments in an effective concentration. For the sake of
simplicity, in order to distinguish clearly between cosmetic and
medicinal use and corresponding products, reference is made to the
legal provisions in the Federal Republic of Germany (e.g. Cosmetics
Regulation, Foods and Drugs Act).
[0016] The use of customary emulsifiers in cosmetic or
dermatological preparations is in itself acceptable. Nevertheless,
emulsifiers, like ultimately any chemical substance, may in certain
circumstances cause allergic reactions or reactions based on
oversensitivity of the user.
[0017] For example, it is known that certain light dermatoses are
triggered by certain emulsifiers, but also by a variety of fats and
simultaneous exposure to sun-light. Such light dermatoses are
also-called "Mallorca acne". There has thus been no lack of
attempts to reduce the amount of customary emulsifiers to a
minimum, in the ideal case even to zero.
[0018] A reduction in the required amount of emulsifier can, for
example, be achieved by taking advantage of the fact that very
finely divided solid particles have an additional stabilizing
action. The solid substance accumulates at the oil/water phase
boundary in the form of a layer, as a result of which coalescence
of the dispersed phases is prevented. It is not the chemical
properties of the solid particles which are of fundamental
importance here, but the surface properties.
[0019] Around 1910, Pickering prepared paraffin/water emulsions
which were stabilized merely by the addition of various solids,
such as basic copper sulphate, basic iron sulphate or other metal
sulphates. This type of emulsion is thus also referred to as a
Pickering emulsion. For this type of emulsion, Pickering postulated
the following conditions:
[0020] (1) The solid particles are only suitable for stabilization
if they are significantly smaller than the droplets of the inner
phase and do not have a tendency to form agglomerates.
[0021] (2) An important property of an emulsion-stabilizing solid
is also its wettability. I.e. in order to stabilize an O/W
emulsion, the solid has, for example, to be more readily wettable
by water than by oil.
[0022] The original forms of Pickering emulsions initially
surfaced, as it were, as undesired secondary effects in a variety
of industrial processes, such as, for example, in secondary oil
recovery, the extraction of bitumen from tar sand and other
separation processes involving two immiscible liquids and fine,
dispersed solid particles. These are generally W/O emulsions which
are stabilized by mineral solids. Accordingly, investigation of
corresponding systems, such as, for example, the oil/water/soot or
oil/water/slate dust systems was initially the focus of research
activity.
[0023] Basic experiments have shown that one characteristic of a
Pickering emulsion is that the solid particles are arranged at the
interface between the two liquid phases where they form, as it
were, a mechanical barrier against the mixing of the liquid
droplets.
[0024] It is a relatively new technical development to use
Pickering emulsions as a base for cosmetic or dermatological
preparations.
[0025] One way of achieving solids stabilization in a cosmetic or
dermatological preparation is, according to May-Alert (Pharmazie in
unserer Zeit [Pharmacy in our time], Vol. 15, 1986, No. 1, 1-7) for
example, to use emulsifier mixtures which contain both anionic and
cationic surfactants. Since mixing anionic and cationic surfactants
always produces precipitates of insoluble, electroneutral
compounds, deliberate precipitation of these neutral surfactants in
the oil/water interface makes it possible to achieve additional
solids stabilization in the sense of a Pickering emulsion.
[0026] EP-A-0 686 391 describes water-in-oil emulsions which are
free from surface-active substances and are stabilized only by
solids. Stabilization is achieved here using spherical
polyalkylsilsesquioxane particles which have a diameter of from 100
nm up to 20 .mu.m. According to the above, these emulsions can be
referred to as Pickering emulsions.
[0027] In addition to the described Pickering emulsions, the prior
art describes further emulsifier-free, finely dispersed cosmetic or
dermatological preparations which are generally referred to as
hydrodispersions. Hydrodispersions are dispersions of a liquid,
semi-solid or solid internal (discontinuous) lipid phase in an
outer aqueous (continuous) phase.
[0028] In the case of hydrodispersions of a liquid lipid phase in
an outer aqueous phase, stability can be ensured, for example, by
constructing, in the aqueous phase, a gel structure in which the
lipid droplets are stably suspended. DE-A 44 25 268 describes
stable finely dispersed, emulsifier-free cosmetic or dermatological
preparations of the oil-in-water type, which, in addition to one
oil phase and one water phase, comprise one or more thickeners from
the group consisting of acrylic polymers, polysaccharides and alkyl
ethers thereof, where these thickeners must not cause any lowering
of the interfacial tension.
[0029] Using similar hydrodispersions as a basis, DE-A 43 03 983
discloses cosmetic or dermatological light protection formulations
which are essentially free from emulsifiers, and which have
inorganic micropigments incorporated into the lipid phase of the
hydrodispersion, which act as UV filter substances.
[0030] The object of the present invention was to extend the prior
art to include cosmetic or dermatological preparations in which it
is not necessary to use any emulsifiers of a conventional type.
[0031] Surprisingly, this object is achieved by cosmetic or
dermatological preparations which are finely dispersed systems of
the oil-in-water or water-in-oil type, comprising
[0032] 1. an oil phase,
[0033] 2. an aqueous phase,
[0034] 3. at least one modified polysaccharide which
[0035] a) has both hydrophilic and lipophilic properties, i.e. has
amphiphilic character, and is dispersible both in water and in oil,
and which
[0036] b) has no thickening properties, and
[0037] 4. at most 0.5% by weight of one or more emulsifiers
[0038] and also optionally comprising further cosmetic or
pharmaceutical auxiliaries, additives and/or active substances.
[0039] According to the invention, it is particularly advantageous
if the preparations comprise significantly less than 0.5% by weight
of one or more emulsifiers. Very particular preference is given to
preparations according to the invention which are entirely free
from emulsifiers in the traditional sense.
[0040] The preparations according to the invention are mixtures of
oils or oil-soluble substances and water or water-soluble
components, which are stabilized by adding modified pqlysaccharides
and which do not have to contain an emulsifier in the traditional
sense. Stabilization is achieved by the modified polysaccharides
attaching themselves to the droplets of the disperse phase and
forming, as it were, a mechanical barrier, which prevents
coalescence of the droplets.
[0041] It was particularly surprising that the preparations
according to the invention can be formulated in a stable manner
even without the addition of further stabilizers, in particular
even without the addition of hydrocolloids. Hydrocolloids are
macromolecules which have a largely linear structure and have
intermolecular forces of interaction which permit secondary and
primary valence bonds between the individual molecules and thus the
formation of a reticulated structure. Some are water-soluble
natural or synthetic polymers which, in aqueous systems, form gels
or viscous solutions.
[0042] It was particularly surprising that in the preparations
according to the invention it is possible to dispense with any use
of acrylate-alkyl acrylate copolymers, in particular those from the
group of so-called carbomers or Carbopols (Carbopol.RTM. is
actually a registered trade mark of B. F. Goodrich Company).
[0043] The preparations according to the invention are extremely
satisfactory preparations in every respect, whose aqueous/fatty
phase ratio can be varied within extraordinarily wide limits and,
in addition, have the advantage over the prior art that large
amounts of oils can be stably incorporated in water. It was also
surprising that by following the teaching disclosed here as regards
technical handling, it is possible to prepare water-in-oil
Pickering emulsions and also oil-in-water Pickering emulsions.
[0044] The water phase proportion of the W/O Pickering emulsions
according to the invention is preferably chosen from the range from
0.5 to 75% by weight, based on the total weight of the
formulations.
[0045] The fatty phase proportion of the O/W Pickering emulsions
according to the invention is preferably chosen from the range from
5 to 75% by weight, very particularly advantageously from the range
from 10 to 70% by weight, in each case based on the total weight of
the formulations.
[0046] For the purposes of the present invention, modified
polysaccharides are obtainable, for example, by reacting starch
with mono-, bi- or polyfunctional reagents or oxidizing agents in
reactions which proceed in a largely polymer-analogous manner.
[0047] Such reactions are essentially based on modifications of the
hydroxyl groups of the polyglucans by etherification,
esterification or selective oxidation. This produces, for example,
so-called starch ethers and starch esters of the general structural
formula 1
[0048] where R may, for example, be a hydrogen and/or an alkyl
and/or aralkyl radical (in the case of the starch ethers) or a
hydrogen and/or an organic and/or inorganic acid radical (in the
case of the starch esters). Starch ethers and starch esters are
advantageous modified polysaccharides for the purposes of the
present invention.
[0049] Particularly advantageous starch ethers are e.g. those
obtainable by etherification of starch with
tetramethylolacetylenediurea and which are referred to as Amylum
non mucilaginosum (nonswelling starch).
[0050] Also particularly advantageous are starch esters and salts
thereof, for example the sodium and/or aluminium salts of
half-esters of starch which have low degrees of substitution, in
particular sodium starch n-octenyl succinate of the structural
formula (I), in which R is characterized by the following structure
2
[0051] and which is available e.g. under the trade name
Amiogum.RTM. 23 from CERESTAR, and aluminium starch octenyl
succinates, in particular those available under the trade names Dry
Flo.RTM. Elite LL and Dry Flo.RTM. PC from CERESTAR.
[0052] It is advantageous to choose the average particle diameter
of the modified polysaccharides used to be less than 20 .mu.m,
particularly advantageously less than 15 .mu.m.
[0053] The list of said modified polysaccharides which can
stabilize Pickering emulsions according to the invention is not of
course intended to be limiting. For the purposes of the present
invention, modified polysaccharides are obtainable in numerous ways
known per se, both of a chemical and a physical nature. In
principle, novel ways are also conceivable for the preparation of
modified polysaccharides according to the invention. It is
essential for the invention that the modified polysaccharides
display amphiphilic properties and that they do not have a
thickening action.
[0054] It is further advantageous, although not obligatory, to
combine the amphiphilic modified polysaccharides according to the
invention with further amphiphilic pigments which may optionally
also contribute to the stabilization of the Pickering
emulsions.
[0055] Such pigments are, for example, micronized inorganic
pigments chosen from the group of amphiphilic metal oxides, in
particular from the group consisting of titanium dioxide, zinc
oxide, silicon dioxide and silicates (e.g. talc), where the metal
oxides may be present either individually or as a mixture. In this
connection, it is essentially unimportant in which of the possible
naturally occurring modifications the amphiphilic metal oxides used
are present.
[0056] The average particle diameter of the amphiphilic metal
oxides used for the combination with polysaccharides according to
the invention is preferably chosen between 1 nm and 200 nm,
particularly advantageously between 5 nm and 100 nm.
[0057] It is advantageous for the purposes of the present invention
to combine the amphiphilic modified polysaccharides according to
the invention with untreated, virtually pure amphiphilic metal
oxide particles, in particular with those which can also be used as
dye in the food industry and/or as absorber of UV radiation in
sunscreens. Examples of advantageous pigments are the zinc oxide
pigments which are available from Merck and those which are
available under the trade names Zinkoxid neutral from Haarmann
& Reimer or NanoX from Harcros Chemical Group.
[0058] A further advantageous untreated pigment is boron nitride.
According to the invention, the modified polysaccharide(s) is/are
preferably combined with one or more of the boron nitrides listed
below:
1 Trade name available from Boron Nitride Powder Advanced Ceramics
Boron Nitride Powder Sintec Keramik Ceram Blanche Kawasaki HCST
Boron Nirtride Stark Trs BN .RTM. Carborundum Wacker-Bornitrid BNP
Wacker-Chemie
[0059] The average particle diameter of the boron nitride particles
used is preferably chosen to be less than 20 .mu.m, in particular
less than 15 .mu.m.
[0060] According to the invention, the combination of modified
polysaccharides with amphiphilic inorganic pigments which have been
surface-treated ("coated") to repel water is also advantageous, the
intention being for the amphiphilic character of these pigments to
be simultaneously formed or retained. This surface treatment may
involve providing the pigments with a thin hydrophobic layer by
methods known per se.
[0061] One such process, which is described below using titanium
dioxide as an example, consists in, for example, producing the
hydrophobic surface layer according to the following reaction
nTiO.sub.2+m(RO).sub.3Si--R'.fwdarw.nTiO.sub.2(surf.)
[0062] n and m are arbitrary stoichiometric parameters, and R and
R' are the desired organic radicals. Particularly advantageous
combination partners are TiO.sub.2 pigments, for example those
coated with aluminium stearate and available under the trade name
MT 100 T from TAYCA.
[0063] Another advantageous coating of the combination partners
consists of dimethylpolysiloxane (also: dimethicone), a mixture of
completely methylated, linear siloxane polymers which have been
terminally blocked with trimethylsiloxy units. The combination of
modified polysaccharides with zinc oxide pigments which have been
coated in this way is particularly advantageous for the purposes of
the present invention. Advantageous combination partners are also
boron nitride particles treated with dimethicone and available from
Carborundum under the trade name Tres BN.RTM. UHP 1106.
[0064] Advantageous coated boron nitride particles are also those
treated with polymethylhydrogensiloxane, a linear polysiloxane,
which is also referred to as methicone. Advantageous boron nitride
particles treated with methicone are, for example, those available
from Carborundum under the trade name Tres BN.RTM. UHP 1107.
[0065] For the purposes of the present invention, it is also
favourable if the inorganic amphiphilic pigments used in addition
to modified polysaccharides have been coated with a mixture of
dimethylpolysiloxane, in particular dimethylpolysiloxane having an
average chain length of from 200 to 350 dimethylsiloxane units, and
silicagel, which is also referred to as simethicone. It is
particularly advantageous if the inorganic pigments have been
additionally coated with aluminium hydroxide or aluminium oxide
hydrate (also: Alumina, CAS No.: 1333-84-2). Particularly
advantageous combination partners are titanium dioxides which have
been coated with simethicone and alumina, it also being possible
for the coating to contain water. One example thereof is the
titanium dioxide available under the trade name Eusolex T2000 from
Merck.
[0066] Also advantageous for the purposes of the present invention
is the combination of modified polysaccharides with a mixture of
different inorganic, amphiphilic pigment types, either within one
crystal, for example as iron mixed oxide or talc (magnesium
silicate), or else by mixing two or more types of metal oxide
within a preparation. Particularly advantageous combination
partners are magnesium silicates, for example those available under
the trade name Talkum Micron from Grolmann.
[0067] The amphiphilic modified polysaccharides according to the
invention can also be advantageously combined with titanium dioxide
pigments which have been coated with octylsilanol, and/or with
silicon dioxide particles which have been surface-treated to repel
water. Silicon dioxide particles suitable for the combination are,
for example, spherical polyalkylsilsesquioxane particles, as
mentioned in European Laid-Open Specification 0 686 391. Such
polyalkylsilsesquioxane particles are, for example, those available
under the trade names Aerosil R972 and Aerosil 200V from
Degussa.
[0068] The modified polysaccharides are further advantageously
combined with microfine polymer particles which are present in the
preparation in the form of solids. Favourable combination partners
for the purposes of the present invention are, for example,
polycarbonates, polyethers, polyethylene, polypropylene, polyvinyl
chloride, polystyrene, polyamides, polyacrylates and the like.
[0069] Combination partners which are suitable according to the
invention are, for example, microfine polyamide particles, in
particular those available under the trade name SP-500 from TORAY.
Also advantageous are Polyamide 6 (also: Nylon 6) and Polyamide 12
(also: Nylon 12) particles. Polyamide 6 is the polyamide
[poly(.epsilon.-caprolactam)] built up from .epsilon.-aminocaproic
acid (6-aminohexanoic acid) or .epsilon.-caprolactam, and Polyamide
12 is a poly(.epsilon.-laurolactam) of .epsilon.-laurolactam. For
the purposes of the present invention, advantageous examples are
Orgasol.RTM.1002 (Polyamide 6) and Orgasol.RTM. 2002 (Polyamide 12)
from ELF ATOCHEM.
[0070] Further advantageous microfine polymer particles which are
suitable for the combination with modified polysaccharides are
microfine polymethacrylates. Such particles are available, for
example, under the trade name POLYTRAP.RTM. from DOW CHEMICAL.
[0071] It is particularly advantageous, although not obligatory, if
the microfine polymer particles used as combination partners have
been surface-coated. This surface treatment may involve providing
the polymer particles with a thin hydrophilic layer by processes
known per se. Advantageous coatings consist, for example, of
titanium dioxide (TiO.sub.2), zirconium dioxide (ZrO.sub.2) or else
further polymers, such as, for example, polymethyl methacrylate.
Particularly advantageous microfine polymer particles for the
purposes of the present invention are, for example, those available
by the process described in Specification U.S. Pat. No. 4,898,913
for the hydrophilic coating of hydrophobic polymer particles.
[0072] The average particle diameter of the microfine polymer
particles used as combination partners is preferably chosen to be
less than 100 .mu.m, particularly advantageously less than 50
.mu.m. In this connection, it is essentially unimportant in which
form (platelets, rods, spherules etc.) the polymer particles used
are present.
[0073] In all of the above cases it is advantageous to choose the
total concentration of all the pigments to be greater than 0.1% by
weight, particularly advantageously between 0.1% by weight and 30%
by weight, based on the total weight of the preparations, where the
concentration of amphiphilic modified polysaccharides according to
the invention is to be chosen, for the purposes of the present
invention, preferably from the range 0.1% by weight to 30% by
weight, advantageously 0.5% by weight to 10% by weight, likewise
based on the total weight of the preparations.
[0074] The oil phase of the Pickering emulsions according to the
invention is advantageously chosen from the group of polar oils,
for examaple from the group of lecithins and fatty acid
triglycerides, namely the triglycerol esters of saturated and/or
unsaturated, branched and/or unbranched alkane carboxylic acids
having a chain length of from 8 to 24, in particular 12 to 18,
carbon atoms. The fatty acid triglycerides may, for example, be
advantageously chosen from the group of synthetic, semisynthetic
and natural oils, such as e.g. olive oil, sunflower oil, soybean
oil, peanut oil, rapeseed oil, almond oil, palm oil, coconut oil,
caster oil, wheatgerm oil, grapeseed oil, thistle oil, evening
primrose oil, macadamia nut oil and the like.
[0075] For the purposes of the present invention, further
advantageous polar oil components may also be chosen from the group
of esters of saturated and/or unsaturated branched and/or
unbranched alkane carboxylic acids having a chain length of from 3
to 30 carbon atoms and saturated and/or unsaturated, branched
and/or unbranched alcohols having a chain length of from 3 to 30
carbon atoms, and from the group of esters of aromatic carboxylic
acids and saturated and/or unsaturated, branched and/or unbranched
alcohols having a chain length of from 3 to 30 carbon atoms. Such
ester oils can then advantageously be chosen from the group
consisting of isopropyl myristate, isopropyl palmitate, isopropyl
stearate, isopropyl oleate, n-butyl stearate, n-hexyl laurate,
n-decyl oleate, isooctyl stearate, isononyl stearate, isononyl
isononanoate, 2-ethylhexyl palmitate, 2-ethylh xyl laurate,
2-hexyldecyl stearate, 2-octyldodecyl palmitate, oleyl oleate,
oleyl erucate, erucyl oleate, erucyl erucate, and synthetic,
semisynthetic and natural mixtures of such esters, such as e.g.
jojoba oil.
[0076] In addition, the oil phase may advantageously be chosen from
the group of dialkyl ethers, the group of saturated or unsaturated,
branched or unbranched alcohol. It is particularly advantageous if
the oil phase of the W/O emulsions according to the invention has a
content of C.sub.12-15-alkyl benzoate or consists entirely of
this.
[0077] Any desired mixtures of such oil and wax components can also
be used advantageously for the purposes of the present invention.
In some instances, it may also be advantageous to use waxes, for
example cetyl palmitate, as the sole lipid component of the oil
phase.
[0078] In addition, the oil phase of the Pickering emulsions
according to the invention may, although it is not obligatory,
likewise advantageously also comprise nonpolar oils, for exampel
those chosen from the group of branched and unbranched hydrocarbons
and hydrocarbon waxes, in particular vaseline (petrolatum),
paraffin oil, squalane and squalene, polyolefins and hydrogenated
polyisobutenes. Of the polyolefins, polydecenes are the preferred
substances.
[0079] In addition, the oil phase may advantageously have a content
of cyclic or linear silicone oils, or consist entirely of such
oils, although it is preferred to use an additional content of
other oil phase components apart from the silicone oil or the
silicone oils.
[0080] Advantageously, cyclomethicone
(octamethylcyclotetrasiloxane) is used as silicone oil to be used
according to the invention. However, other silicone oils are also
to be used advantageously for the purposes of the present
invention, for example hexamethylcyclotrisiloxane,
polydimethylsiloxane, poly(methylphenyl-siloxane).
[0081] The Pickering emulsions according to the invention can be
used as bases for cosmetic or dermatological formulations. These
can have the customary composition and be used, for example, for
the treatment and care of the skin, as lip care product, as
deodorant and as make-up or make-up remover product in decorative
cosmetics or as light protection preparation. For use, the cosmetic
and dermatological preparations according to the invention are
applied to the skin in sufficient amount in the manner customary
for cosmetics.
[0082] Accordingly, for the purposes of the present invention,
cosmetic or topical dermatological compositions may, depending on
their structure, be used, for example, as skin-protection cream,
cleansing milk, sunscreen lotion, nutrient cream, day or night
cream, etc. Where appropriate, it is possible and advantageous to
use the compositions according to the invention as bases for
pharmaceutical formulations.
[0083] The cosmetic and dermatological preparations according to
the invention may comprise cosmetic auxiliaries, as customarily
used in such preparations, e.g. preservatives, bactericides,
perfumes, antifoams, dyes, pigments which have a colouring effect,
thickeners, plasticizers, moisturizing and/or moisture-retaining
substances, fats, oils, waxes or other customary constituents of a
cosmetic or dermatological formulation, such as alcohols, polyols,
polymers, foam stabilizers, electrolytes, organic solvents or
silicone derivatives.
[0084] A surprising property of the preparations according to the
invention is that they are very good vehicles for cosmetic or
dermatological active ingredients into the skin, advantageous
active ingredients being antioxidants which are able to protect the
skin against oxidative stress.
[0085] According to the invention, the preparations advantageously
comprise one or more antioxidants. Antioxidants which are
favourable, but nevertheless optional, are all antioxidants which
are suitable or customary for cosmetic and/or dermatological
applications. Here, it is advantageous to use antioxidants as the
sole active ingredient class whenever, for example, a cosmetic or
dermatological application is at the fore, such as e.g. the control
of oxidative stressing of the skin. It is, however, also favourable
to provide the stick preparations according to the invention with a
content of one or more antioxidants whenever the preparations are
to serve another purpose, e.g. as deodorants or sunscreens.
[0086] The antioxidants are particularly advantageously selected
from the group consisting of amino acids (e.g. glycine, histidine,
tyrosine, tryptophan) and their derivatives, imidazoles, (e.g.
urocanic acid) and their derivatives, peptides, such as
D,L-carnosine, D-carnosine, L-carnosine and their derivatives (e.g.
anserine), carotenoids, carotenes (e.g. .alpha.-carotene,
.beta.-carotene, lycopene) and their derivatives, chlorogenic acid
and its derivatives, lipoic acid and its derivatives (e.g.
dihydrolipoic acid), aurothioglucose, propylthiouracil and other
thiols (e.g. thioredoxin, glutathione, cysteine, cystine, cystamine
and their glycosyl, N-acetyl, methyl, ethyl, propyl, amyl, butyl
and lauryl, palmitoyl, oleyl, .gamma.-linoleyl, cholesteryl and
glyceryl esters) and their salts, dilauryl thiodipropionate,
distearyl thiodipropionate, thiodipropionic acid and its
derivatives (esters, ethers, peptides, lipids, nucleotides,
nucleosides and salts) and sulphoximine compounds (e.g. buthionine
sulphoximines, homocysteine sulphoximine, buthionine sulphones,
penta-, hexa-, hepta-thionine sulphoximines) in very low tolerated
doses (e.g. pmol to .mu.mol/kg), and also (metal) chelating agents
(e.g. .alpha.-hydroxyfatty acids, palmitic acid, phytic acid,
lactofenin), .alpha.-hydroxy acids (e.g. citric acid, lactic acid,
malic acid), humic acid, bile acid, bile extracts, bilirubin,
biliverdin, EDTA, EGTA and their derivatives, unsaturated fatty
acids and their derivatives (e.g. .gamma.-linolenic acid, linoleic
acid, oleic acid), folic acid and its derivatives, ubiquinone and
ubiquinol and their derivatives, vitamin C and derivatives (e.g.
ascorbyl palmitate, Mg ascorbyl phosphate, ascorbyl acetate),
tocopherols and derivatives (e.g. vitamin E acetate), vitamin A and
derivatives (vitamin A palmitate) and coniferyl benzoate of
benzoin, rutinic acid and its derivatives, .alpha.-glycosylrutin,
ferulic acid, furfurylideneglucitol, carnosine, butylated
hydroxytoluene, butylated hydroxyanisole, nordihydroguaiac acid,
nordihydroguaiaretic acid, trihydroxybutyrophenone, uric acid and
its derivatives, mannose and its derivatives, zinc and its
derivatives (e.g. ZnO, ZnSO.sub.4), selenium and its derivatives
(e.g. selenomethionine), stilbenes and their derivatives (e.g.
stilbene oxide, trans-stilbene oxide), and the derivatives (salts,
esters, ethers, sugars, nucleotides, nucleosides, peptides and
lipids) of said active substances which are suitable according to
the invention.
[0087] The amount of the abovementioned antioxidants (one or more
compounds) in the preparations according to the invention is
preferably from 0.001 to 30% by weight, particularly preferably
from 0.05 to 20% by weight, in particular 1-10% by weight, based on
the total weight of the preparation.
[0088] If vitamin E and/or its derivatives are used as the
antioxidant or antioxidants, their respective concentrations are
advantageously chosen from the range of 0.001-10% by weight, based
on the total weight of the formulation.
[0089] If vitamin A or vitamin A derivatives or carotenes or their
derivatives are used as the antioxidant or antioxidants, their
respective concentrations are advantageously chosen from the range
of 0.001-10% by weight, based on the total weight of the
formulation.
[0090] According to the invention, the active ingredients (one or
more compounds) can also very advantageously be chosen from the
group of lipophilic active ingredients, in particular from the
following group:
[0091] Acetylsalicylic acid, atropine, azulene, hydrocortisone and
derivatives thereof, e.g. hydrocortisone-17 valerate, vitamins,
e.g. ascorbic acid and derivatives thereof, vitamins of the B and D
series, very favourably vitamin B.sub.1, vitamin B.sub.12 and
vitamin D.sub.1, but also bisabolol, unsaturated fatty acids,
namely the essential fatty acids (often also called vitamin F), in
particular gamma-linolenic acid, oleic acid, eicosapentaenoic acid,
docosahexanoic acid and derivatives thereof, chloramphenicol,
caffeine, prostaglandins, thymol, camphor, extracts or other
products of vegetable and animal origin, e.g. evening primrose oil,
borage oil or currant seed oil, fish oils, cod-liver oil or also
ceramides and ceramide-like compounds and so on.
[0092] It is also advantageous to choose the active ingredients
from the group of refatting substances, for example purcellin oil,
Eucerit.quadrature. and Neocerit.quadrature..
[0093] The list of said active ingredients or active ingredient
combinations which can be used in the Pickering emulsions according
to the invention is not of course intended to be limiting.
[0094] Cosmetic and dermatological preparations which are in the
form of a sunscreen are also favourable. These preferably comprise
at least one UV-A filter substance and/or at least one UV-B filter
substance and/or at least one further inorganic pigment selected
from the group consisting of the oxides of iron, zirconium,
silicon, manganese, aluminium, cerium and mixtures thereof and also
modifications in which the oxides are the active agents.
[0095] For the purposes of the present invention, it is, however,
also advantageous to provide such cosmetic and dermatological
preparations whose main purpose is not protection against sunlight,
but which nevertheless comprise substances which protect against
UV. For example, UV-A and UV-B filter substances are commonly
incorporated into day cream.
[0096] The preparations according to the invention can
advantageously comprise further substances which absorb UV
radiation in the UV-B range, the total amount of filter substances
being, for example, from 0.1% by weight to 30% by weight,
preferably from 0.5 to 10% by weight, based on the total weight of
the preparations, in order to provide cosmetic preparations which
protect the hair and/or the skin from the whole region of
ultraviolet radiation.
[0097] If the emulsions according to the invention contain UV-B
filter substances, the latter may be oil-soluble or water-soluble.
Examples of oil-soluble UV-B filters which are advantageous
according to the invention are:
[0098] .xi. 3-benzylidenecamphor derivatives, preferably
3-(4-methylbenzyl-idene)camphor,
[0099] 3-benzylidenecamphor;
[0100] .xi. 4-aminobenzoic acid derivatives, preferably
2-ethylhexyl 4-(dimethylamino)benzoate, amyl
4-(dimethylamino)benzoate;
[0101] .xi. esters of cinnamic acid, preferably 2-ethylhexyl
4-methoxycinnamate, isopentyl 4-methoxycinnamate;
[0102] .xi. esters of salicylic acid, preferably 2-ethylhexyl
salicylate, 4-isopropylbenzyl salicylate, homomenthyl
salicylate;
[0103] .xi. derivatives of benzophenone, preferably
2-hydroxy-4-methoxybenzophenone,
2-hydroxy-4-methoxy-4'-methylbenzophenon- e,
2,2'-dihydroxy-4-methoxy-benzophenone;
[0104] .xi. esters of benzalmalonic acid, preferably
di(2-ethylhexyl) 4-methoxy-benzalmalonate;
[0105] .xi. triazine derivatives symmetrically or unsymmetrically
substituted with regard to the C.sub.3 axis of the parent triazine
substance, preferably tris(2-ethylhexyl)
4,4',4"-(1,3,5-triazine-2,4,6-tr- iyltriimino)trisbenzoate
(symmetrical) and 2,4-bis.perp.[4-(2-ethylhexylox-
y)-2-hydroxy]phenyl}-6-(4-methoxyphenyl)-1,3,5-triazine,
2,4-bis{[4-(3-sulphonato)-2-hydroxypropyloxy)-2-hydroxy]phenyl}-6-(4-meth-
oxyphenyl)-1,3,5-triazine sodium salt,
2,4-bis{[4-(3-(2-propyloxy)-2-hydro-
xypropyloxy)-2-hydroxy]phenyl}-6-(4-methoxyphenyl)-1,3,5-triazine,
2,4-bis{[4-(2-ethylhexyloxy)-2-hydroxy]phenyl}-6-[4-(2-methoxyethylcarbox-
yl)phenylamino]-1,3,5-triazine,
2,4-bis{[4-(3-(2-propyloxy)-2-hydroxypropy-
loxy)-2-hydroxy]-phenyl}-6-[4-(2-ethylcarboxyl)phenylamino]-1,3,5-triazine-
,
2,4-bis{([4-(2-ethylhexyloxy)-2-hydroxy]phenyl}-6-(1-methylpyrrol-2-yl)--
1,3,5-triazine,
2,4-bis{[4-tris(trimethyl-syloxysilylpropyloxy)-2-hydroxy]-
phenyl}-6-(4-methoxyphenyl)-1,3,5-triazine,
2,4-bis{[4-(2"-methylpropenylo-
xy)-2-hydroxy]phenyl}-6-(4-methoxyphenyl)-1,3,5-triazine,
2,4-bis{[4-(1',1',1',3',5',5',5'-heptamethylsiloxy-2-methylpropyloxy)-2-h-
ydroxy]phenyl}-6-(4-methoxyphenyl)-1,3,5-triazine
(unsymmetrical),
[0106] .xi. benzotriazole derivatives, preferably
2,2'-methylenebis(6-(2H-- benzotriazol-2-yl)
4-(1,1,3,3-tetramethylbutyl)phenol)
[0107] .xi. and UV filters bonded to polymers.
[0108] Examples of advantageous water-soluble UV-B filters are:
[0109] .xi. Salts of 2-phenylbenzimidazole-5-sulphonic acid, such
as its sodium, potassium or its triethanolammonium salt, and also
the sulphonic acid itself;
[0110] .xi. Sulphonic acid derivatives of 3-benzylidenecamphor,
such as e.g. 4-(2-oxo-3-bomylidenemethyl)benzenesulphonic acid,
2-methyl-5-(2-oxo-3-bomylidene-methyl)sulphonic acid and their
salts.
[0111] The list of said UV-B filters, which may be used in the
Pickering emulsions according to the invention, is of course not
intended to be limiting.
[0112] It can also be advantageous to use, in the Pickering
emulsions according to the invention, UV-A filters which have
hitherto been customarily present in cosmetic preparations. These
substances are preferably derivatives of dibenzoylmethane, in
particular
1-(4'-tert-butylphenyl)-3-(4'-methoxyphenyl)propane-1,3-dione and
1-phenyl-3-(4'-isopropylphenyl)propane-1,3-dione.
[0113] Further advantageous UV-A filter substances are
phenylene-1,4-bis(2-benzimidazyl)-3,3'-5,5'-tetrasulphonic acid:
3
[0114] and its salts, particularly the corresponding sodium,
potassium or triethanolammonium salts, in particular
phenylene-1,4-bis(2-benzimidazyl)- -3,3'-5,5'-tetrasulphonic acid
bis-sodium salt: 4
[0115] and 1,4-di(2-oxo-10-sulpho-3-bomylidenemethyl)benzene and
salts thereof (in particular the corresponding 10-sulphato
compounds, in particular the corresponding sodium, potassium or
triethanolammonium salt), which is also referred to as
benzene-1,4-di(2-oxo-3-bornylidenemet- hyl-10-sulphonic acid) and
is characterized by the following structure: 5
[0116] Advantageous UV filter substances are also so-called
broad-band filters, i.e. filter substances which absorb both UV-A
and UV-B radiation.
[0117] A broad-band filter which is to be used advantageously is,
for example, ethylhexyl 2-cyano-3,3-diphenylacrylate (octocrylene),
which is obtainable from BASF under the name Uvinul.RTM. N 539 and
is characterized by the following structure: 6
[0118] Preparations which contain UV-A filters or so-called
broad-band filters are also provided by the invention. The amounts
which may be used are as for the UV-B combination.
[0119] Preparations which contain UV-A filters or so-called
broad-band filters are also provided by the invention. The amounts
which may be used are as for the UV-B combination.
[0120] Preparations according to the invention can also be
advantageously used as bases for cosmetic deodorants and
antiperspirants, so that a particular embodiment of the present
invention relates to Pickering emulsions as bases for cosmetic
deodorants.
[0121] Cosmetic deodorants are used to control body odour which
arises when fresh sweat, which is in itself odourless, is
decomposed by microorganisms. Customary cosmetic deodorants are
based on various modes of action.
[0122] In antiperspirants, astringents, mainly aluminium salts,
such as aluminium hydroxychloride (aluchlorhydrate), reduce sweat
production.
[0123] The use of antimicrobial substances in cosmetic deodorants
can reduce the bacterial flora of the skin. In an ideal situation,
only the microorganisms which cause the odour should be effectively
reduced. The flow of sweat itself is not influenced as a result,
and in ideal circumstances, only microbial decomposition of sweat
is stopped temporarily.
[0124] The combination of astringents and antimicrobial substances
in one and the same composition is also common.
[0125] All active ingredients common for deodorants or
antiperspirants can advantageously be used, for example odour
concealers, such as customary perfum constituents, odour absorbers,
for example the phyllosilicates described in Patent Laid-Open
Specification DE 40 09 347, of these in particular montmorillonite,
kaolinite, illite, beidellite, nontronite, saponite, hectorite,
bentonite, smectite, and also, for example, zinc salts of
ricinoleic acid. Antibacterial agents are also suitable for
incorporation into the W/O emulsion sticks according to the
invention. Advantageous substances are, for example,
2,4,4'-trichloro-2'-hydroxy diphenyl ether (Irgasan),
1,6-di(4-chlorophenylbiguanido)hexane (chlorhexidine),
3,4,4'-trichlorocarbanilide, quatemary ammonium compounds, oil of
cloves, mint oil, thyme oil, triethyl citrate, Famesol
(3,7,11-trimethyl-2,6,10-dodecatrien-1-ol), and the active
ingredients or active ingredient combinations described in Patent
Laid-Open Specifications DE-37 40 186, DE-39 38 140, DE-42 04 321,
DE-42 29 707, DE-43 09 372, DE-44 11 664, DE-195 41 967, DE-195 43
695, DE-195 43 696, DE-195 47 160, DE-196 02 108, DE-196 02 110,
DE-196 02 111, DE-196 31 003, DE-196 31 004 and DE-196 34 019, and
Patent Specifications DE-42 29 737, DE-42 37 081, DE-43 24 219,
DE-44 29 467, DE-44 23 410 and DE-195 16 705. Sodium
hydrogencarbonate can also be used advantageously.
[0126] The list of said active ingredients or active ingredient
combinations which can be used in the Pickering emulsions according
to the invention is not of course intended to be limiting.
[0127] The cosmetic deodorants according to the invention can be
present in the form of hydrous, cosmetic preparations which can be
applied from normal containers.
[0128] The amount of antiperspirant active ingredients or
deodorants (one or more compounds) in the preparations is
preferably 0.01 to 30% by weight, particularly preferably 0.1-20%
by weight, in particular 1-10% by weight, based on the total weight
of the preparation.
[0129] The sticks according to the invention are also excellent
vehicles for dermatological active ingredients. In particular, they
are suitable as carriers for substances effective against acne.
Acne is a skin disorder of many different forms and causes,
characterized by non-inflamed and inflamed bumps, originating from
blocked hair follicles (comedones) which can lead to the formation
of pustules, abscesses and scars. The most frequent is Acne
vulgaris which occurs mainly in puberty. Causative conditions for
Acne vulgaris are the keratinization and blocking of the hair
follicle opening, the production of sebum, which is dependent on
the level of male sex hormones in the blood, and the production of
free fatty acids and tissue-damaging enzymes by bacteria
(Propionibacterium acnes).
[0130] It is therefore advantageous to add to the preparations
according to the invention substances effective against acne which
are effective, for example, against Propionibacterum acnes (for
example those described in DE-A 42 29 707, DE-A 43 05 069, DE-A 43
07 976, DE-A 43 37 711, DE-A 43 29 379), but also other substances
which are effective against acne, for example all-trans-retinoic
acid, 13-cis-retinoic acid and related substances) or
anti-inflammatory active ingredients, for example batyl alcohol
(.alpha.-octadecyl glyceryl ether), selachyl alcohol
(.alpha.-9-octadecenyl glyceryl ether), chimyl alcohol
(.alpha.-hexadecyl glyceryl ether) and/or bisabolol, and
antibiotics and/or keratolytics.
[0131] Keratolytics are substances which soften keratinized skin
(such as e.g. warts, corns, calluses and the like) so that it can
be removed more easily or so that it falls off or peels off.
[0132] All of the common substances effective against acne can be
used advantageously, in particular benzoyl peroxide,
bituminosulphonates (ammonium, sodium and calcium salts of shale
oil sulphonic acids), salicylic acid (2-hydroxybenzoic acid),
miconazole
(1-[2-(2,4-dichlorobenzyloxy)-2-(2,4-dichloro-phenyl)ethyl]imidazole)
and derivatives, adapalene
(6-[3-(1-adamantyl)-4-methoxyphenyl]-2-naphthoic acid), azelaic
acid (nonanedioic acid), mesulphene (2,7-dimethylthianthrene,
C.sub.14H.sub.12S.sub.2), and aluminium oxide, zinc oxide and/or
finely dispersed sulphur.
[0133] The amount of antiacne agents (one or more compounds) in the
preparations is preferably 0.01 to 30% by weight, particularly
preferably 0.1-20% by weight, in particular 1-10% by weight, based
on the total weight of the preparation.
[0134] The following examples serve to illustrate the present
invention, without limiting it. The numerical values in the
examples indicate percentages by weight, based on the total weight
of the respective preparations.
EXAMPL S
[0135]
2 1 2 3 4 5 6 W/O W/O W/O O/W O/W O/W Titanium dioxide (Eusolex 4 6
2 2 T2000) Zinc oxide 4 4 Silica (Aerosil R972) 1 0.5 Talc (Talkum
Micron) 2 Boron nitride 1 Sodium corn starch 2 1 2 5 1 1 n-octenyl
succinate Orgasol .RTM. 1002 (Polyamide 1 1 6) Caprylic/capric
triglyceride 5 5 5 20 20 20 Octyldodecanol 10 5 20 15 Mineral oil
10 5 20 20 Butylene glycol caprylate/ 10 10 20 7 caprate
C.sub.12-15-alkyl benzoate 10 10 10 5 20 Methylbenzylidenecamphor 3
4 Octyltriazone 1 4 Dibenzoylmethane 2 2 Preservative 0.5 0.5 0.5
0.5 0.5 0.5 Glycerol 5 10 3 5 5 5 Phenylbenzimidazolsulphonic 1 2
acid Carbomer 0.1 NaOH 45% strength solution 0.3 0.1 1.3 in water
EDTA solution 1 1 Water ad ad ad ad ad ad 100 100 100 100 100
100
* * * * *