Dispersion of polymer particles in a non-aqueous medium and
cosmetic use thereof
The present invention relates to a dispersion of polymer particles dispersed in a
non-aqueous medium, and also to a cosmetic composition comprising such a d is
persion.
It is known practice to use in cosmetics dispersions of polymer particles of nanometric
size, in organic media such as hydrocarbon-based oils, for instance hydrocarbons.
Polymers are especially used as film-forming agents in makeup products
such as mascaras, eyeliners, eyeshadows or lipsticks.
Document EP-A-749 747 describes in the examples dispersions in hydrocarbonbased
oils (liquid paraffin, isododecane) of acrylic polymers stabilized with polystyrene/
copoly(ethylene-propylene) diblock copolymers. However, when the solids
(polymer + stabilizer) content exceeds 25% by weight, the dispersion then be
comes too viscous, thus giving rise to formulation difficulties in cosmetic products
on account of a large change in the viscosity of the final composition of these
products. In addition, the film obtained after application of the dispersion to the
skin is slightly glossy.
Document WO-A-201 0/046 229 describes dispersions in isododecane of acrylic
polymers stabilized with block and especially triblock stabilizing polymers of acrylic
monomers. In the examples, according to Example 1A, the stabilizing polymer is
prepared by reversible chain-transfer controlled radical polymerization. This
polymerization method is difficult to perform on an industrial scale since it requires
a large number of intermediate purification steps to obtain the final polymer d is
persion.
There is thus a need for a stable dispersion of acrylic polymer stabilized in a no n
aqueous medium comprising a hydrocarbon-based oil, which is easy to manufac
ture industrially, and which makes it possible to obtain a film that has good cosmetic
properties, especially good gloss.
The Applicant has discovered that novel dispersions of C 1-C4 alkyl (meth)acrylate
polymer particles stabilized with particular stabilizers based on isobornyl
(meth)acrylate polymer in a hydrocarbon-based oil have good stability, especially
after storage for seven days at room temperature (25°C), are easy to manufacture
industrially without using a large number of synthetic steps and also make it possi
ble to obtain a film after application to a support which has good cosmetic proper
ties, in particular good gloss, good resistance to oils, and which is non-tacky.
One subject of the present invention is thus a dispersion of particles of at least one
polymer that is surface-stabilized with a stabilizer in a non-aqueous medium con
taining at least one hydrocarbon-based oil, the polymer of the particles being a C 1-
C4 alkyl (meth)acrylate polymer; the stabilizer being an isobornyl (meth)acrylate
polymer chosen from isobornyl (meth)acrylate homopolymer and statistical copol
ymers of isobornyl (meth)acrylate and of C 1-C4 alkyl (meth)acrylate present in an
isobornyl (meth)acrylate/C1 -C4 alkyl (meth)acrylate weight ratio of greater than 4 .
For these statistical stabilizing copolymers, the defined weight ratio makes it possible
to obtain a polymer dispersion that is stable, especially after storage for sev
en days at room temperature (25°C).
Another subject of the invention is a composition comprising, in a physiologically
acceptable medium, a polymer particle dispersion as defined previously.
A subject of the invention is also a process for the non-therapeutic cosmetic treat
ment of keratin materials, comprising the application to the keratin materials of a
composition as defined previously. The treatment process is in particular a pro
cess for caring for or making up keratin materials.
The dispersions according to the invention thus consist of particles, which are
generally spherical, of at least one surface-stabilized polymer, in a non-aqueous
medium.
The polymer of the particles is a C 1-C4 alkyl (meth)acrylate polymer.
The C 1-C4 alkyl (meth)acrylate monomers may be chosen from methyl
(meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl
(meth)acrylate, n-butyl (meth)acrylate and tert-butyl (meth)acrylate.
A C 1-C4 alkyl acrylate monomer is advantageously used. Preferentially, the polymer
of the particles is a methyl acrylate and/or ethyl acrylate polymer.
The polymer of the particles may also comprise an ethylenically unsaturated acid
monomer or the anhydride thereof, chosen especially from ethylenically unsaturat
ed acid monomers comprising at least one carboxylic, phosphoric or sulfonic acid
function, such as crotonic acid, itaconic acid, fumaric acid, maleic acid, maleic an
hydride, styrenesulfonic acid, vinylbenzoic acid, vinylphosphoric acid, acrylic acid,
methacrylic acid, acrylamidopropanesulfonic acid or acrylamidoglycolic acid, and
salts thereof.
Preferably, the ethylenically unsaturated acid monomer is chosen from
(meth)acrylic acid, maleic acid and maleic anhydride.
The salts may be chosen from salts of alkali metals, for example sodium or potassium;
salts of alkaline-earth metals, for example calcium, magnesium or strontium;
metal salts, for example zinc, aluminium, manganese or copper; ammonium salts
of formula NH +; quaternary ammonium salts; salts of organic amines, for instance
salts of methylamine, dimethylamine, trimethylamine, triethylamine, ethylamine, 2-
hydroxyethylamine, bis(2-hydroxyethyl)amine or tris(2-hydroxyethyl)amine; lysine
or arginine salts.
The polymer of the particles may thus comprise or consist essentially of 80% to
100% by weight of C 1-C4 alkyl (meth)acrylate and of 0 to 20% by weight of eth
ylenically unsaturated acid monomer, relative to the total weight of the polymer.
According to a first embodiment of the invention, the polymer consists essentially
of a polymer of one or more C 1-C4 alkyl (meth)acrylate monomers.
According to a second embodiment of the invention, the polymer consists essen
tially of a copolymer of C 1-C4 (meth)acrylate and of (meth)acrylic acid or maleic
anhydride.
The polymer of the particles may be chosen from:
methyl acrylate homopolymers
ethyl acrylate homopolymers
methyl acrylate/ethyl acrylate copolymers
methyl acrylate/ethyl acrylate/acrylic acid copolymers
methyl acrylate/ethyl acrylate/maleic anhydride copolymers
methyl acrylate/acrylic acid copolymers
ethyl acrylate/acrylic acid copolymers
methyl acrylate/maleic anhydride copolymers
ethyl acrylate/maleic anhydride copolymers.
Advantageously, the polymer of the particles is a non-crossl inked polymer.
The polymer of the particles of the dispersion preferably has a number-average
molecular weight ranging from 2000 to 10 000 000 and preferably ranging from
150 000 to 500 000.
The polymer of the particles may be present in the dispersion in a content ranging
from 2 1% to 58.5% by weight and preferably ranging from 36% to 42% by weight,
relative to the total weight of the dispersion.
The stabilizer is an isobornyl (meth)acrylate polymer chosen from isobornyl
(meth)acrylate homopolymer and statistical copolymers of isobornyl (meth)acrylate
and of C 1-C4 alkyl (meth)acrylate present in an isobornyl (meth)acrylate/C1 -C4
alkyl (meth)acrylate weight ratio of greater than 4, preferably greater than 4,5,
more preferably greater or equal to 5 . Advantageously, the said weight ratio ranges
from 4.5 to 19, and preferably from 5 to 19, and more preferably from 5 to 12 .
Advantageously, the stabilizer is chosen from:
isobornyl acrylate homopolymers
statistical copolymers of isobornyl acrylate/methyl acrylate
statistical copolymers of isobornyl acrylate/methyl acrylate/ethyl acrylate
statistical copolymers of isobornyl methacrylate/methyl acrylate
in the weight ratio described previously.
The stabilizing polymer preferably has a number-average molecular weight ranging
from 10 000 to 400 000 and preferably ranging from 20 000 to 200 000.
The stabilizer is in contact with the surface of the polymer particles and thus
makes it possible to stabilize these particles at the surface in order to keep these
particles in dispersion in the non-aqueous medium of the dispersion. The stabilizer
is a compound distinct form the polymer of the particles.
Advantageously, the combination of the stabilizer + polymer of the particles pre
sent in the dispersion comprises from 10% to 50% by weight of polymerized
isobornyl (meth)acrylate and from 50% to 90% by weight of polymerized C1-C4
alkyl (meth)acrylate, relative to the total weight of the combination of the stabilizer
+ polymer of the particles.
Preferentially, the combination of the stabilizer + polymer of the particles present in
the dispersion comprises from 15% to 30% by weight of polymerized isobornyl
(meth)acrylate and from 70% to 85% by weight of polymerized C 1-C4 alkyl
(meth)acrylate, relative to the total weight of the combination of the stabilizer +
polymer of the particles.
The oily medium of the polymer dispersion comprises a hydrocarbon-based oil.
The hydrocarbon-based oil is an oil that is liquid at room temperature (25°C).
The term "hydrocarbon-based oil" means an oil formed essentially from, or even
consisting of, carbon and hydrogen atoms, and optionally oxygen and nitrogen at
oms, and not containing any silicon or fluorine atoms. It may contain alcohol, ester,
ether, carboxylic acid, amine and/or amide groups.
The hydrocarbon-based oil may be chosen from:
hydrocarbon-based oils containing from 8 to 16 carbon atoms, and especially:
- branched Cs-Ci4 alkanes, for instance Cs-Ci4 isoalkanes of petroleum origin (also
known as isoparaffins), for instance isododecane (also known as 2,2,4,4,6-
pentamethylheptane), isodecane, isohexadecane and, for example, the oils sold
under the trade name Isopar or Permethyl,
- linear alkanes, for instance n-dodecane (C1 2) and n-tetradecane (C14) sold by
Sasol under the respective references Parafol 12-97 and Parafol 14-97, and also
mixtures thereof, the undecane-tridecane mixture, the mixtures of n-undecane
(C1 1) and of n-tridecane (C1 3) obtained in Examples 1 and 2 of patent application
WO 2008/1 55 059 from the company Cognis, and mixtures thereof,
- short-chain esters (containing from 3 to 8 carbon atoms in total) such as ethyl
acetate, methyl acetate, propyl acetate or n-butyl acetate,
- hydrocarbon-based oils of plant origin such as triglycerides consisting of fatty acid
esters of glycerol, the fatty acids of which may have chain lengths varying from
C4 to C 24 , these chains possibly being linear or branched, and saturated or unsatu
rated; these oils are especially heptanoic or octanoic acid triglycerides, or alterna
tively wheatgerm oil, sunflower oil, grapeseed oil, sesame seed oil, corn oil, apricot
oil, castor oil, shea oil, avocado oil, olive oil, soybean oil, sweet almond oil, palm
oil, rapeseed oil, cottonseed oil, hazelnut oil, macadamia oil, jojoba oil, alfalfa oil,
poppy oil, pumpkin oil, marrow oil, blackcurrant oil, evening primrose oil, millet oil,
barley oil, quinoa oil, rye oil, safflower oil, candlenut oil, passion-flower oil and
musk rose oil; shea butter; or else caprylic/capric acid triglycerides, for instance
those sold by the company Stearineries Dubois or those sold under the names
Miglyol 8 10®, 8 12® and 8 18® by the company Dynamit Nobel,
- synthetic ethers containing from 10 to 40 carbon atoms;
- linear or branched hydrocarbons of mineral or synthetic origin, such as petroleum
jelly, polydecenes, hydrogenated polyisobutene such as Parleam®, squalane and
liquid paraffins, and mixtures thereof,
- synthetic esters such as oils of formula R1COOR2 in which R represents a linear
or branched fatty acid residue containing from 1 to 40 carbon atoms and R2 repre
sents an, in particular, branched hydrocarbon-based chain containing from 1 to 40
carbon atoms, on condition that R + R2 > 0, for instance purcellin oil (cetostearyl
octanoate), isopropyl myristate, isopropyl palmitate, C12 to C15 alkyl benzoates,
hexyl laurate, diisopropyl adipate, isononyl isononanoate, 2-ethylhexyl palmitate,
isostearyl isostearate, 2-hexyldecyl laurate, 2-octyldecyl palmitate, 2-octyldodecyl
myristate, alkyl or polyalkyi heptanoates, octanoates, decanoates or ricinoleates
such as propylene glycol dioctanoate; hydroxylated esters such as isostearyl lac
tate, diisostearyl malate and 2-octyldodecyl lactate; polyol esters and pentaerythritol
esters,
- fatty alcohols that are liquid at room temperature, with a branched and/or unsatu
rated carbon-based chain containing from 12 to 26 carbon atoms, for instance octyldodecanol,
isostearyl alcohol, oleyl alcohol, 2-hexyldecanol, 2-butyloctanol and
2-undecylpentadecanol.
Advantageously, the hydrocarbon-based oil is apolar (thus formed solely from car
bon and hydrogen atoms).
The hydrocarbon-based oil is preferably chosen from hydrocarbon-based oils co n
taining from 8 to 16 carbon atoms, preferably from 8 to 14 carbon atoms, in part ic
ular the apolar oils described previously.
Preferentially, the hydrocarbon-based oil is isododecane.
The polymer particles of the dispersion preferably have an average size, especial
ly a number-average size, ranging from 50 to 500 nm, especially ranging from 75
to 400 nm and better still ranging from 100 to 250 nm.
In general, the dispersion according to the invention may be prepared in the fol
lowing manner, which is given as an example.
The polymerization may be performed in dispersion, i.e. by precipitation of the po l
ymer during formation, with protection of the formed particles with a stabilizer.
In a first step, the stabilizing polymer is prepared by mixing the constituent mono
mers) of the stabilizing polymer, with a radical initiator, in a solvent known as the
synthesis solvent, and by polymerizing these monomers. In a second step, the
constituent monomer(s) of the polymer of the particles are added to the stabilizing
polymer formed and polymerization of these added monomers is performed in the
presence of the radical initiator.
When the non-aqueous medium is a non-volatile hydrocarbon-based oil, the
polymerization may be performed in an apolar organic solvent (synthesis solvent),
followed by adding the non-volatile hydrocarbon-based oil (which should be miscible
with the said synthesis solvent) and selectively distilling off the synthesis so l
vent.
A synthesis solvent which is such that the monomers of the stabilizing polymer
and the free-radical initiator are soluble therein, and the polymer particles obtained
are insoluble therein, so that they precipitate therein during their formation, is thus
chosen.
In particular, the synthesis solvent may be chosen from alkanes such as heptane
or cyclohexane.
When the non-aqueous medium is a volatile hydrocarbon-based oil, the polymeri
zation may be performed directly in the said oil, which thus also acts as synthesis
solvent. The monomers should also be soluble therein, as should the free-radical
initiator, and the polymer of the particles obtained should be insoluble therein.
The monomers are preferably present in the synthesis solvent, before polymeriza
tion, in a proportion of 5-20% by weight. The total amount of monomers may be
present in the solvent before the start of the reaction, or part of the monomers may
be added gradually as the polymerization reaction proceeds.
The free-radical initiator may especially be azobisisobutyronitrile or tert-butyl peroxy-
2-ethylhexanoate.
The polymerization may be performed at a temperature ranging from 70 to 0°C.
The polymer particles are surface-stabilized, when they are formed during the
polymerization, by means of the stabilizer.
The stabilization may be performed by any known means, and in particular by d i
rect addition of the stabilizer, during the polymerization.
The stabilizer is preferably also present in the mixture before polymerization of the
monomers of the polymer of the particles. However, it is also possible to add it
continuously, especially when the monomers of the polymer of the particles are
also added continuously.
From 10% to 30% by weight and preferably from 15% to 25% by weight of stabi
lizer may be used relative to the total weight of monomers used (stabilizer + po ly
mer of the particles).
The polymer particle dispersion advantageously comprises from 30% to 65% by
weight and preferably from 40% to 60% by weight of solids, relative to the total
weight of the dispersion.
Advantageously, the oily dispersion may comprise a plasticizer chosen from tri-nbutyl
citrate, tripropylene glycol monomethyl ether (INCI name: PPG-3 methyl
ether) and trimethyl pentaphenyl trisiloxane (sold under the name Dow Corning
PH-1 555 HRI Cosmetic Fluid by the company Dow Corning). These plasticizers
make it possible to improve the mechanical strength of the polymer film.
The plasticizer may be present in the oily dispersion in an amount ranging from
5% to 50% by weight, relative to the total weight of the polymer of the particles.
The polymer dispersion obtained according to the invention may be used in a
composition comprising a physiologically acceptable medium, in particular in a
cosmetic composition.
The term "physiologically acceptable medium" is intended to mean a medium that
is compatible with human keratin materials, for instance the skin, the lips, the nails,
the eyelashes, the eyebrows or the hair.
The term "cosmetic composition" is understood to mean a composition that is
compatible with keratin materials, which has a pleasant colour, odour and feel and
which does not cause unacceptable discomfort (stinging, tautness or redness) l ia
ble to discourage the consumer from using it.
The term "keratin materials" is understood to mean the skin (body, face, contour of
the eyes, scalp), head hair, eyelashes, eyebrows, bodily hairs, nails or lips.
The composition according to the invention may comprise a cosmetic additive
chosen from water, fragrances, preserving agents, fillers, dyestuffs, UV-screening
agents, oils, waxes, surfactants, moisturizers, vitamins, ceramides, antioxidants,
free-radical scavengers, polymers and thickeners.
The composition according to the invention may comprise the polymer of the d is
persion in a content ranging from 1% to 50% by weight and preferably ranging
from 10% to 45% by weight relative to the total weight of the composition.
Advantageously, the composition according to the invention is a makeup composi
tion, in particular a lip makeup composition, a mascara, an eyeliner, an eyeshadow
or a foundation.
According to one embodiment, the composition according to the invention is an
anhydrous composition. The term "anhydrous composition" means a composition
containing less than 2% by weight of water, or even less than 0.5% of water, and
is especially free of water. Where appropriate, such small amounts of water may
especially be introduced by ingredients of the composition that may contain resid
ual amounts thereof.
The invention is illustrated in greater detail in the examples that follow.
Evaluation of the cosmetic properties of the oily dispersions :
The oily dispersion to be evaluated was placed on a contrast card (for example
that sold under the reference Byko-charts by the company Byk-Gardner) and the
film deposited was dried for 24 hours at room temperature (25°C). The dry film has
a thickness of about 50 miti .
The gloss of the film was measured using a glossmeter (three angles Refo 3 /
Refo 3D from Labomat) at an angle of 20°.
The resistance of the film to the fatty substance was determined by depositing on
the dry film three drops of olive oil onto the black part of the contrast card. The
drops were left in contact with the dry film for 10 minutes, 30 minutes and 60
minutes, respectively, and the oil drop was then wiped and the appearance of the
area of the film that was in contact with the oil was observed. If the film was damaged
by the oil drop, the polymer film is considered as not being resistant to olive
oil.
The tacky aspect of the polymer film was evaluated by touching the dry film with a
finger.
All the percentages of reagents described in the examples are weight percent
ages.
Example 1
In a first step, 1300 g of isododecane, 337 g of isobornyl acrylate, 28 g of methyl
acrylate and 3.64 g of tert-butyl peroxy-2-ethylhexanoate (Trigonox 2 1S from
Akzo) were placed in a reactor. The isobornyl acrylate/nnethyl acrylate mass ratio
is 92/8. The mixture was heated at 90°C under argon with stirring.
After 2 hours of reaction, 1430 g of isododecane were added to the reactor feed
stock and the mixture was heated to 90°C.
In a second step, a mixture of 1376 g of methyl acrylate, 1376 g of isododecane
and 13.75 g of Trigonox 2 1S were run in over 2 hours 30 minutes, and the mixture
was left to react for 7 hours. 3.3 litres of isododecane were then added and part of
the isododecane was evaporated off to obtain a solids content of 50% by weight.
A dispersion of methyl acrylate particles stabilized with a statistical copolymer sta
bilizer containing 92% isobornyl acrylate and 8% methyl acrylate in isododecane
was obtained.
The oily dispersion contains in total (stabilizer + particles) 80% methyl acrylate and
20% isobornyl acrylate.
The polymer particles of the dispersion have a number-average size of about 160
nm.
The dispersion is stable after storage for 7 days at room temperature (25°C).
The film obtained with the oil dis ersion has the followin ro erties:
Resistant to fatty sub
72 Non-tacky
stances
Example 2
A dispersion of polymer in isododecane was prepared according to the preparation
method of Example 1, using:
Step 1: 275.5 g of isobornyl acrylate, 11.6 g of methyl acrylate, 11.6 g of ethyl
acrylate, 2.99 g of Trigonox 2 1, 750 g of isododecane; followed by addition, after
reaction, of 750 g of isododecane.
Step 2 : 539.5 g of methyl acrylate, 539.5 g of ethyl acrylate, 10.8 g of Trigonox
2 1S, 1079 g of isododecane. After reaction, addition of 2 litres of isododecane and
evaporation to obtain a solids content of 35% by weight.
A dispersion in isododecane of methyl acrylate/ethyl acrylate (50/50) copolymer
particles stabilized with an isobornyl acrylate/methyl acrylate/ethyl acrylate (92/4/4)
statistical copolymer stabilizer was obtained.
The oily dispersion contains in total (stabilizer + particles) 40% methyl acrylate,
40% ethyl acrylate and 20% isobornyl acrylate.
The dispersion is stable after storage for 7 days at room temperature (25°C).
The film obtained with the oil dis ersion has the followin ro erties:
Example 3
A dispersion of polymer in isododecane was prepared according to the preparation
method of Example 1, using:
Step 1: 3 15.2 g of isobornyl acrylate, 12.5 g of methyl acrylate, 12.5 g of ethyl
acrylate, 3.4 g of Trigonox 2 1, 540 g of isododecane, 360 g of ethyl acetate; fol
lowed by addition, after reaction, of 540 g of isododecane and 360 g of ethyl acetate.
Step 2 : 303 g of methyl acrylate, 776 g of ethyl acrylate, 157 g of acrylic acid, 11 g
of Trigonox 2 1S, 741 .6 g of isododecane and 494.4 g of ethyl acetate. After reaction,
addition of 3 litres of an isododecane/ethyl acetate mixture (60/40
weight/weight) and total evaporation of the ethyl acetate and partial evaporation of
the isododecane to obtain a solids content of 44% by weight.
A dispersion in isododecane of methyl acrylate/ethyl acrylate/acrylic acid
(24.5/62.8/12.7) copolymer particles stabilized with an isobornyl acrylate/methyl
acrylate/ethyl acrylate (92/4/4) statistical copolymer stabilizer was obtained.
The oily dispersion contains in total (stabilizer + particles) 10% acrylic acid, 20%
methyl acrylate, 50% ethyl acrylate and 20% isobornyl acrylate.
The dispersion is stable after storage for 7 days at room temperature (25°C).
The film obtained with the oil dis ersion has the followin ro erties:
Example 4
A dispersion of polymer in isododecane was prepared according to the preparation
method of Example 1, using:
Step 1: 3 15.2 g of isobornyl acrylate, 12.5 g of methyl acrylate, 12.5 g of ethyl
acrylate, 3.4 g of Trigonox 2 1, 540 g of isododecane, 360 g of ethyl acetate; fol
lowed by addition, after reaction, of 540 g of isododecane and 360 g of ethyl ace
tate.
Step 2 : 145 g of methyl acrylate, 934 g of ethyl acrylate, 157 g of acrylic acid,
12.36 g of Trigonox 2 1S, 741 .6 g of isododecane and 494.4 g of ethyl acetate. Af
ter reaction, addition of 3 litres of an isododecane/ethyl acetate mixture (60/40
weight/weight) and total evaporation of the ethyl acetate and partial evaporation of
the isododecane to obtain a solids content of 44% by weight.
A dispersion in isododecane of methyl acrylate/ethyl acrylate/acrylic acid
( 1 1.7/75.6/12.7) copolymer particles stabilized with an isobornyl acrylate/methyl
acrylate/ethyl acrylate (92/4/4) statistical copolymer stabilizer was obtained.
The oily dispersion contains in total (stabilizer + particles) 10% acrylic acid, 10%
methyl acrylate, 60% ethyl acrylate and 20% isobornyl acrylate.
The dispersion is stable after storage for 7 days at room temperature (25°C).
The film obtained with the oil dis ersion has the followin ro erties:
Example 5
A dispersion of polymer in isododecane was prepared according to the preparation
method of Example 1, using:
Step 1: 48 g of isobornyl acrylate, 2 g of methyl acrylate, 2 g of ethyl acrylate, 0.52
g of Trigonox 2 1, 57.6 g of isododecane, 38.4 g of ethyl acetate; followed by add i
tion, after reaction, of 540 g of isododecane and 360 g of ethyl acetate.
Step 2 : 98 g of methyl acrylate, 73 g of ethyl acrylate, 25 g of maleic anhydride,
1.96 g of Trigonox 2 1S, 50.4 g of isododecane and 33.60 g of ethyl acetate. After
reaction, addition of 1 litre of an isododecane/ethyl acetate mixture (60/40
weight/weight) and total evaporation of the ethyl acetate and partial evaporation of
the isododecane to obtain a solids content of 46.2% by weight.
A dispersion in isododecane of methyl acrylate/ethyl acrylate/maleic anhydride
(50/37.2/1 2.8) copolymer particles stabilized with an isobornyl acrylate/methyl
acrylate/ethyl acrylate (92/4/4) statistical copolymer stabilizer was obtained.
The oily dispersion contains in total (stabilizer + particles) 10% maleic anhydride,
30% methyl acrylate, 40% ethyl acrylate and 20% isobornyl acrylate.
The dispersion is stable after storage for 7 days at room temperature (25°C).
The film obtained with the oil dis ersion has the followin ro erties:
Example 6
A dispersion of polymer in isododecane was prepared according to the preparation
method of Example 1, using:
Step 1: 48.5 g of isobornyl methacrylate, 4 g of methyl acrylate, 0.52 g Trigonox
2 1, 115 g of isododecane; followed by addition, after reaction, of 80 g of isododec
ane.
Step 2 : 190 g of methyl acrylate, 1.9 g of Trigonox 2 1S, 190 g of isododecane. Af
ter reaction, addition of 1 litre of isododecane and partial evaporation of the isodo
decane to obtain a solids content of 48% by weight.
A dispersion in isododecane of methyl acrylate polymer particles stabilized with an
isobornyl methacrylate/methyl acrylate (92/8) statistical copolymer stabilizer was
obtained.
The oily dispersion contains in total (stabilizer + particles) 80% methyl acrylate and
20% isobornyl methacrylate.
The dispersion is stable after storage for 7 days at room temperature (25°C).
The film obtained with the oil dis ersion has the followin ro erties:
Examples 7 and 8 (invention) and 9 and 10 (outside the invention)
Several oily dispersions of polymethyl acrylate stabilized with a stabilizer contain
ing isobornyl acrylate and optionally methyl acrylate were prepared, according to
the procedure of Example 1, by varying the mass ratio of isobornyl acrylate and
methyl acrylate and observing the stability of the dispersion obtained as a function
of the chemical constitution of the stabilizer.
All the dispersions comprise in total (stabilizer + particles) 80% methyl acrylate
and 20% isobornyl acrylate.
Example 7 :
Step 1: 50 g of isobornyl acrylate, 0.5 g Trigonox 2 1, 96 g of isododecane; fo l
lowed by addition, after reaction, of 80 g of isododecane.
Step 2 : 200 g of methyl acrylate, 2 g of Trigonox 2 1S, 200 g of isododecane. After
reaction, addition of 80 g of isododecane and evaporation to obtain a solids con
tent of 3 1% by weight.
A dispersion in isododecane of polymethyl acrylate particles stabilized with a polyisobornyl
acrylate stabilizer was obtained.
Example 8 :
Step 1: 48.5 g of isobornyl acrylate, 8.5 g of methyl acrylate, 0.57 g Trigonox 2 1,
115 g of isododecane; followed by addition, after reaction, of 75 g of isododecane.
Step 2 : 185.5 g of methyl acrylate, 1.85 g of Trigonox 2 1S, 185.5 g of isododec
ane. After reaction, addition of 75 g of isododecane and evaporation to obtain a
solids content of 3 1% by weight.
A dispersion in isododecane of polymethyl acrylate particles stabilized with an
isobornyl acrylate/methyl acrylate (85/1 5) statistical copolymer stabilizer was obtained.
Example 9 (outside the invention):
Step 1: 48.5 g of isobornyl acrylate, 12 g of methyl acrylate, 0.6 g Trigonox 2 1, 115
g of isododecane; followed by addition, after reaction, of 60 g of isododecane.
Step 2 : 182 g of methyl acrylate, 1.82 g of Trigonox 2 1S, 182 g of isododecane.
After reaction, addition of 60 g of isododecane and evaporation to obtain a solids
content of 3 1% by weight.
A dispersion in isododecane of polymethyl acrylate particles stabilized with an
isobornyl acrylate/methyl acrylate (80/20) statistical copolymer stabilizer was obtained.
Example 10 (outside the invention):
Step 1: 48.5 g of isobornyl acrylate, 2 1 g of methyl acrylate, 0.7 g Trigonox 2 1, 130
g of isododecane; followed by addition, after reaction, of 65 g of isododecane.
Step 2 : 173 g of methyl acrylate, 1.73 g of Trigonox 2 1S, 173 g of isododecane.
After reaction, addition of 65 g of isododecane and evaporation to obtain a solids
content of 3 1% by weight.
A dispersion in isododecane of polymethyl acrylate particles stabilized with an
isobornyl acrylate/methyl acrylate (70/30) statistical copolymer stabilizer was obtained.
The stability 12 hours after the end of synthesis of the oily dispersions of polymethyl
acrylate of Examples 1 and 7 to 10 was compared, and the following results
were obtained.
The results obtained show that the dispersions of polymethyl acrylate in isododecane
are stable when the stabilizer is an isobornyl acrylate homopolymer or an
isobornyl acrylate/methyl acrylate copolymer with an isobornyl acrylate/methyl
acrylate weight ratio > 80/20.
Moreover, the film obtained with the oily dispersions of Examples 7 and 8 have
the followin ro erties:
Examples 11 and 12 (outside the invention)
Tests were performed with other monomers bearing a cyclic group by replacing
the isobornyl acrylate, performing step 1 of Example 1, i.e. preparing a cyclic
monomer/methyl acrylate (92/8) statistical copolymer stabilizer. All the stabilizers
prepared in isododecane led to a medium that set to a solid in the form of a viscous
precipitate. This shows that such stabilizers are unsuitable for forming an oily
dispersion since they are incompatible with isododecane, in contrast with the stabi
lizers prepared in Examples 1 to 8 described previously.
Example 13:
Polymer dispersion of Example 1
Tri-n-butyl citrate
The film obtained after application to a contrast card and drying for 24 hours at
25°C and 45% relative humidity has good tensile strength. The film is also glossy,
resistant to olive oil and non-tacky.
Example 14 :
Polymer dispersion of Example 1
Tripropylene glycol monomethyl ether
The film obtained after application to a contrast card and drying for 24 hours at
25°C and 45% relative humidity has good tensile strength. The film is also glossy,
resistant to olive oil and non-tacky.
Example 15:
Polymer dispersion of Example 1 96%
Trimethyl pentaphenyl trisiloxane
(Dow Corning PH-1 555 HRI Cosmetic
Fluid from Dow Corning) 4%
The film obtained after application to a contrast card and drying for 24 hours at
25°C and 45% relative humidity has good tensile strength. The film is also glossy,
resistant to olive oil and non-tacky.
Example 16:
A skin makeup composition comprising the ingredients below is prepared:
Polymer dispersion of Example 1 9 1.2%
Tripropylene glycol monomethyl ether 3.8%
Iron oxides 5%
The composition applied to the skin makes it possible to obtain a glossy makeup
film that is resistant to oils and non-tacky.
The polymer dispersion of Example 1 may be replaced with the dispersions of Examples
2 to 8 .
Example 17:
A lip makeup composition comprising the ingredients below is prepared:
Polymer dispersion of Example 1 9 1.2%
Trimethyl pentaphenyl trisiloxane 3.8%
Isononyl isononanoate 5%
Red 7 1%
The composition applied to the lips makes it possible to obtain a glossy makeup
film that is resistant to oils and non-tacky.
The polymer dispersion of Example 1 may be replaced with the dispersions of Ex
amples 2 to 8 .
Example 18:
An eyelash makeup composition comprising the ingredients below is prepared:
Polymer dispersion of Example 1 57.6%
Tri-n-butyl citrate 2.4%
Isododecane 20%
Black iron oxides 20%
The composition applied to the eyelashes makes it possible to obtain a glossy
makeup film that is resistant to oils and non-tacky.
The polymer dispersion of Example 1 may be replaced with the dispersions of Ex
amples 2 to 8 .
CLAIMS
1. Dispersion of particles of at least one polymer that is surface-stabilized with a
stabilizer in a non-aqueous medium containing at least one hydrocarbon-based oil,
the polymer of the particles being a C1-C4 alkyl (meth)acrylate polymer; the stabi
lizer being an isobornyl (meth)acrylate polymer chosen from isobornyl
(meth)acrylate homopolymer and statistical copolymers of isobornyl (meth)acrylate
and of C 1-C4 alkyl (meth)acrylate present in an isobornyl (meth)acrylate/C1 -C4
alkyl (meth)acrylate weight ratio of greater than 4 .
2 . Dispersion according to Claim 1, characterized in that the polymer of the parti
cles is a methyl acrylate and/or ethyl acrylate polymer.
3 . Dispersion according to either of the preceding claims, characterized in that the
polymer of the particles comprises an ethylenically unsaturated acid monomer or
the anhydride thereof, preferably chosen from (meth)acrylic acid, maleic acid and
maleic anhydride.
4 . Dispersion according to one of the preceding claims, characterized in that the
polymer of the particles comprises from 80% to 100% by weight of C 1-C4 alkyl
(meth)acrylate and from 0 to 20% by weight of ethylenically unsaturated acid
monomer, relative to the total weight of the polymer.
5 . Dispersion according to one of the preceding claims, characterized in that the
polymer of the particles is chosen from:
methyl acrylate homopolymers
ethyl acrylate homopolymers
methyl acrylate/ethyl acrylate copolymers
methyl acrylate/ethyl acrylate/acrylic acid copolymers
methyl acrylate/ethyl acrylate/maleic anhydride copolymers
methyl acrylate/acrylic acid copolymers
ethyl acrylate/acrylic acid copolymers
methyl acrylate/maleic anhydride copolymers
ethyl acrylate/maleic anhydride copolymers.
6 . Dispersion according to one of the preceding claims, characterized in that the
polymer of the particles is present in a content ranging from 5% to 70% by weight
and preferably ranging from 30% to 60% by weight, relative to the total weight of
the dispersion.
7 . Dispersion according to one of the preceding claims, characterized in that the
polymer particles have an average size ranging from 50 to 500 nm, especially
ranging from 75 to 400 nm and better still ranging from 100 nm to 250 nm.
8 . Dispersion according to one of the preceding claims, characterized in that the
stabilizer is a statistical copolymer of isobornyl (meth)acrylate and of C 1-C4 alkyl
(meth)acrylate present in an isobornyl (meth)acrylate/C1 -C4 alkyl (meth)acrylate
weight ratio greater than or equal to 5 .
9 . Dispersion according to one of the preceding claims, characterized in that the
stabilizer is chosen from:
isobornyl acrylate homopolymers
statistical copolymers of isobornyl acrylate/methyl acrylate
statistical copolymers of isobornyl acrylate/methyl acrylate/ethyl acrylate
statistical copolymers of isobornyl methacrylate/methyl acrylate.
10 . Dispersion according to one of the preceding claims, characterized in that the
combination of the stabilizer + polymer of the particles present in the dispersion
comprises from 10% to 50% by weight of polymerized isobornyl (meth)acrylate
and from 50% to 90% by weight of polymerized C 1-C4 alkyl (meth)acrylate, rela
tive to the total weight of the combination of the stabilizer + polymer of the particles.
11. Dispersion according to one of the preceding claims, characterized in that the
hydrocarbon-based oil is chosen from apolar hydrocarbon-based oils containing
from 8 to 16 carbon atoms.
12 . Dispersion according to one of the preceding claims, characterized in that the
hydrocarbon-based oil is isododecane.
13 . Dispersion according to one of the preceding claims, characterized in that it
comprises from 30% to 65% by weight and preferably from 40% to 60% by weight
of solids, relative to the total weight of the dispersion.
14. Dispersion according to one of the preceding claims, characterized in that it
comprises a plasticizer chosen from tri-n-butyl citrate, tripropylene glycol monomethyl
ether and trimethyl pentaphenyl trisiloxane.
15 . Composition comprising, in a physiologically acceptable medium, a polymer
dispersion according to one of the preceding claims.
16 . Composition according to the preceding claim, characterized in that it compris
es a cosmetic additive chosen from water, fragrances, preserving agents, fillers,
dyestuffs, UV-screening agents, oils, waxes, surfactants, moisturizers, vitamins,
ceramides, antioxidants, free-radical scavengers, polymers and thickeners.
17 . Non-therapeutic cosmetic process for treating keratin materials, comprising the
application to the keratin materials of a composition according to either of Claims
15 and 16, in particular for caring for or making up keratin materials.