 |
Description  |
|
|
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a cosmetic composition, and, more particularly,
to a cosmetic composition which comprises a specific acryl-silicone graft
copolymer having an organosiloxane side chain, and is useful for various
applications to the skin, hair, nails, and the like.
The invention also relates to a gel composition which comprises the
specific acryl-silicone graft copolymer and a low-viscosity silicone oil.
2. Description of the Backcround Art
Cosmetics are broadly classified into basic cosmetics such as lotions,
creams, emulsions, packs, and the like; makeup cosmetics such as
foundations, lipsticks, rouges, eyeliners, mascaras, eyeshadows, eyebrow
pencils, manicures, face powders, and the like; and hair cosmetics.
Since basic cosmetics have the purpose of imparting moisturizing and
softening effects to the skin, characteristics strongly required for them
are good water-retaining capability as well as superior stability and
retentiveness of the humectant and softening components. Emulsion
cosmetics are widely used as basic cosmetics, makeup cosmetics, and the
like, in which the characteristics of emulsion are utilized.
Neither o/w-type nor w/o-type emulsions, however, can provide a composition
having sufficient stability over time, good water-repellency, and
excellent sensation upon use at the same time.
Since one of the major purposes of makeup cosmetics is to improve the
outward appearance of the object to which they are applied, such as the
skin and nails, characteristics demanded of makeup cosmetics include a
good sensation upon use; superior water-repellency, water-resistance, and
oil-resistance; and good retentiveness of the makeup.
Many of conventional makeup cosmetics such as foundations, eyeliners,
mascaras, eyeshadows, nail enamels, and so on do not give a good sensation
upon use and do not produce a cosmetic film which is sufficiently
water-resistant, oil-resistant, and friction-resistant.
In view of this situation, the present inventors have undertaken extensive
studies for the development of a cosmetic composition having good
stability over time, imparting an excellent sensation upon use, and
possessing superior resistance to water and oil. As a result, the present
inventors have found that a cosmetic composition and a gel composition
into which a specific type of acryl-silicone graft copolymer is
incorporated satisfied these requirements for cosmetics.
SUMMARY OF THE INVENTION
Accordingly, an object of this invention is to provide a cosmetic
composition comprising an acryl-silicone graft copolymer which is prepared
by radical polymerization of (i) a dimethylpolysiloxane compound having a
polymerizable radical group on one of the molecular chain terminals and
(ii) a radically polymerizable monomer comprising as major components an
acrylate or methacrylate, or both [such a graft copolymer is herein
referred to as component (A)].
Another object of the present invention is to provide various types of
cosmetic compositions in which one or more components selected from the
group consisting of a lowviscosity silicone oil [component (B)], a
partially crosslinked organopolysiloxane polymeric compound [component
(C)], a low-boiling-point oil [component (D)], a volatile solvent
[component (E)], a cosmetic powder material [component (F)], a polyacrylic
emulsion of the type increasing its viscosity in alkaline conditions,
[component (G)], a volatile hydrocarbon [component (H)], a surface active
agent [component (I)], and water [component (J)] are used in combination
with the above component (A).
Still another object of the present invention is to provide a gel
composition which comprises said acryl-silicone graft copolymer and a
low-viscosity silicone oil.
Other objects, features and advantages of the invention will hereinafter
become more readily apparent from the following description.
DETAILED DESCRIPTION OF THE INVENTION AND PREFERRED EMBODIMENTS
Component (A), the acryl-silicone graft copolymer, of the present invention
can be prepared by the radical copolymerization of (i) a
dimethylpolysiloxane compound having a polymerizable radical group on one
of the molecular chain terminals and (ii) a radically polymerizable
monomer comprising as major components an acrylate or methacrylate, or
both. The dimethylpolysiloxane compound (i) having a polymerizable radical
group on one of the molecular chain terminals is represented by the
following general formula (I),
##STR1##
wherein R.sup.1 represents a methyl group or a hydrogen atom, R.sup.2
represents a divalent, linear or branched hydrocarbon group having 1-10
carbon atoms and optionally containing one or two ether bonds therein, and
1 is a value of 3-300.
Typical examples of the group represented by R.sup.2 include: --CH.sup.2
--, --CH.sub.2 --, --CH.sub.2 --, --CH.sub.2 --, --CH.sub.2 --.sub.10 --,
--CH.sub.2 --CH(CH.sub.3)--CH.sub.2 --, --CH.sub.2 CH.sub.2 OCH.sub.2
CH.sub.2 CH.sub.2 --, --CH.sub.2 CH.sub.2 OCH.sub.2 CH.sub.2
CH(CH.sub.3)CH.sub.2 --, --CH.sub.2 CH.sub.2 OCH.sub.2 CH.sub.2 OCH.sub.2
CH.sub.2 CH.sub.2 --, and the like. The value 1 is usually 3-300. The
preferable range is between 5 and 100. If the value for 1 is less than 3,
the resulting acryl-silicone graft copolymer has a poor mutual solubility
with a low-viscosity silicone oil and a low-boiling-point oil and produces
a film having only insufficient water-resistance. If the value of 1 is
greater than 300, the resulting acryl-silicone graft copolymer has only a
low glass transition temperature. This precludes the copolymer from
producing a film having sufficient strength and from producing a solid gel
composition having a good quality even though a low-viscosity silicone oil
is incorporated.
A process for preparing this dimethylpolysiloxane compound having a
polymerizable radical group on one of the molecular chain terminals and
represented by the general formula (I) can be exemplified by the
de-hydrochloric acid reaction of a (meth)acrylate-substituted chlorosilane
compound of the formula (II) and a dimethylpolysiloxane a terminal of
which is substituted by a hydroxyl group of the formula (III) according to
a conventional method:
##STR2##
wherein R.sub.1 represents a methyl group or a hydrogen atom, R.sub.2
represents a divalent, linear or branched hydrocarbon group having 1-10
carbon atoms and optionally containing one or two ether bonds therein,
##STR3##
wherein 1 is a value of 3-300.
The following compounds are given as examples of preferable
dimethylpolysiloxane compounds having a polymerizable radical group on one
of the molecular chain terminals.
##STR4##
A radically polymerizable monomer (ii) comprising an acrylate or
methacrylate, or both as its major components is a compound having one
radically polymerizable unsaturated bond in its molecule. Given as
examples of acrylates or methacrylates which can be present in the
compound are alkyl(meth)acrylates such as methyl(meth)acrylate,
ethyl(meth)acrylate, n-butyl(meth)acrylate, 2ethylhexyl(meth)acrylate, and
the like, hydroxyalkyl(meth)acrylates such as
2-hydroxyethyl(meth)acrylate, 2-hydroxypropyl(meth)acrylate, and the like,
and perfluoroalkyl(meth)acrylate having a C.sub.1-10 fluorocarbon chain.
Here, the expression "comprising an acrylate, a methacrylate, or both as
major components" means that the radically polymerizable monomer
"comprises at least 50% by weight or more of one or more acrylates or
methacrylates." If the total amount of acrylates and methacrylates
contained in the monomer is less than 50% by weight, the resulting
copolymer cannot produce an acceptable film or solid gel composition.
Various other compounds besides acrylates or methacrylates can be used as
required for the radically polymerizable monomer of the present invention.
Given as examples of such radically polymerizable monomers are styrene,
substituted styrenes, vinyl acetate, (meth)acrylic acid, maleic anhydride,
maleic acid esters, fumaric acid esters, vinyl chloride, vinylidene
chloride, ethylene, propylene, butadiene, acrylonitrile, fluorinated
olefins, and the like.
In the present invention, a ratio by weight of (i) a dimethylpolysiloxane
compound having a polymerizable radical group on one of the molecular
chain terminals and (ii) a radically polymerizable monomer comprising as
major components an acrylate or methacrylate, or both, i.e., (i):(ii), in
the copolymer should be in the range of 1:19-2:1. If the ratio is less
than 1:19, the resulting acrylsilicone graft copolymer has a poor mutual
solubility with a low-viscosity silicone oil (B) and a low-boiling-point
oil (D) and produces a film having only insufficient water-resistance. If
the ratio is more than 2:1, on the other hand, the resulting
acryl-silicone graft copolymer cannot produce a film or solid gel
composition having high strength.
The copolymerization reaction of (i) a dimethylpolysiloxane compound having
a polymerizable radical group on one of the molecular chain terminals and
(ii) a radically polymerizable monomer comprising as major components an
acrylate or methacrylate, or both can be carried out using a conventional
radical polymerization initiator such as benzoylperoxide, lauroylperoxide,
azobisisobutyronitrile, or the like. Solution polymerization, emulsion
polymerization, suspension polymerization, and bulk polymerization can be
acceptable. Among these, solution polymerization is preferable because of
its capability of readily adjusting the molecular weight of the resulting
graft copolymer to an optimum range. A solvent which can be used in the
reaction is an aromatic hydrocarbon such as benzene, toluene, xylene, or
the like; a ketone such as methyl ethyl ketone, methyl isobutyl ketone, or
the like; an ester such as ethyl acetate, isobutyl acetate, or the like;
or an alcohol such as isopropanol, butanol, or the like. Such solvents may
be used independently or two or more types of solvents may be used in a
mixture.
The polymerization reaction is carried out at a temperature range of
50.degree.-180.degree. C., preferably of 60.degree.-120.degree. C. The
reaction is usually completed in 5-10 hours under these conditions. The
acryl-silicone graft copolymer thus produced has a weight average
molecular weight of about 3,000-200,000, preferably of about
5,000-100,000, converted to polystyrene by gel permeation chromatography
analysis. A preferable range of the glass transition temperature of the
copolymer is between -30.degree. and +60.degree. C.
A stable gel composition can be produced by incorporating a low-viscosity
silicone oil (B) into the copolymer (A). The gel composition is solid,
soft, and stable, and gives a smooth and fresh sensation upon use.
There are no specific limitations as to the type of a low-viscosity
silicone oil for use. Any silicone oils having a viscosity below 50 cs,
preferably of 2-20 cs, can suitably be used. The use of a large amount of
a higher viscosity silicone oil may decrease the mutual solubility of the
silicone oil and copolymer (A). This results in an oily sensation and
tends to impair the feeling upon use of the resulting product. Examples of
low-viscosity silicone oils include low-polymerization-degree
dimethylpolysiloxanes, methylphenylpolysiloxane, and the like. If
necessary, two or more of low-viscosity silicone oils can be used in
combination.
The gel composition of the present invention can be prepared by blending
component (A) and a low-viscosity silicone oil (B) and heating the mixture
to dissolution, or by dissolving component (A) into a volatile organic
solvent and adding a low-viscosity silicone oil (B) to the solution,
followed by removal of the volatile organic solvent. The ratio of
component (A) and a low-viscosity silicone oil (B) varies depending on the
types of component (A). Normally, the ratio by weight of (A):(B) is
5:95-70:30, with a preferable range being 15:85-40:60. If the amount of
the low-viscosity silicone oil (B) is too large in proportion to copolymer
(A), the resulting gel composition becomes fluid so that a gel composition
having acceptable solidity cannot be obtained. If the amount of copolymer
(A) is too large, on the other hand, a soft, flexible solid gel
composition cannot be obtained.
In the present invention, a solid gel composition having varied solidity,
ranging from a comparatively hard gel to a comparatively soft gel, can be
produced by changing the proportion of component (A) and a low-viscosity
silicone oil (B), or the acryl chain length, silicone chain length, or the
amount of the substitution in the copolymer. If the proportion of the
copolymer (A) is increased or a larger amount of methylmathacrylate is
introduced into the acryl chains of the copolymer, a solid gel giving
suitable solidity to touch is obtained. On the other hand, a soft,
flexible gel composition can be produced by introducing a large amount of
butylacrylate or 2-ethylhexylacrylate into the acryl chains of the
copolymer.
The solid gel composition thus prepared gives a soft, stable, smooth, and
fresh sensation upon use. By using the solid gel composition as a
component, very useful cosmetic compositions, in which the excellent
characteristics of the solid gel are fully exhibited, can be produced.
Such cosmetics include basic cosmetics for use with the face, hands, and
feet such as creams, emulsions, and the like; hair cosmetics such as hair
treatment agents and the like; and makeup cosmetics such as foundations,
rouges, face powders, lipsticks, eyeliners, eyeshadows, mascaras, and the
like. The kinds of cosmetics to which the gel composition of the present
invention is applied are by no means limited to those given here.
The amount of the solid gel to be incorporated into a cosmetic composition
can be determined depending on the use to which the cosmetic composition
is directed within a range of 1-100% by weight. The use of the solid gel
alone may achieve the purpose of the present invention.
A gel composition comprising: (A) 5-60% by weight of an acryl-silicone
graft copolymer, (B) 30-94.8% by weight of a low-viscosity silicone oil,
and (C) 0.2-40% by weight of a partially cross-linked organopolysiloxane
polymeric compound is particularly useful for incorporating in a cosmetic
composition. When such a gel composition is incorporated in an amount of
30-100% by weight, the cosmetic composition gives a smooth and fresh
feeling upon use, is easy to use, and exhibits excellent stability over
time.
The amount of 5-60% by weight of an acryl-silicone graft copolymer is
preferable, this is because the intended effect cannot be produced if the
amount is less than 5% by weight and the cosmetic composition becomes too
hard at an amount exceeding 60% by weight such that the solid cosmetic
composition cannot readily be applied. In addition, a solid cosmetic
composition of this type gives the feeling of a thick membrane after
application.
Silicone oils of the type mentioned above can be used as a low-viscosity
silicone oil (B) either independently or in combination. A desirable range
to be incorporated is 30-94.8% by weight.
A partially cross-linked organopolysiloxane polymeric compound (C) used in
the cosmetic composition of the present invention is that having a
cross-linking three-dimensional structure, encompassing a low-viscosity
silicone oil, and capable of forming a gel.
The partially cross-linked organopolysiloxane polymeric compound which can
be used may include, for example, an organopolysiloxane polymeric compound
which is insoluble in benzene and has a three-dimensional cross-linked
structure in which benzene of an equivalent or more amount of the
organopolysiloxane polymeric compound itself may be contained. Such a
polymeric compound can be prepared by the cross-linking reaction of
organopolysiloxane, may contain three-dimensional cross-linking
structures, and consists of R.sub.2 SiO and RSiO.sub.1.5 units. The
polymeric compound may also contain R.sub.3 SiO.sub.0.5, SiO.sub.2, or
both.
Given as examples of R in the above organopolysiloxane constituting unit
are the hydrogen atom, an alkyl group such as methyl, ethyl, propyl, or
the like, an aryl group such as phenyl, tolyl, or the like, and an
unsaturated aliphatic group such as vinyl group. The organosiloxane unit
may contain either one type of R, or two or more different types of R.
In order for the organopolysiloxane to be insoluble in benzene and to take
a three-dimensional cross-linked structure in which benzene of an
equivalent or more amount of the organopolysiloxane polymeric compound
itself may be contained, it is essential that the ratio of either
RSiO.sub.1.5, SiO.sub.2, or RSiO.sub.1.5 plus SiO.sub.2, and either
R.sub.2 SiO, R.sub.3 SiO.sub.0.5, or R.sub.2 SiO plus R.sub.3 SiO.sub.0.5,
be in a suitable range. If the amount of either RSiO.sub.1.5, SiO.sub.2,
or RSiO.sub.1.5 plus SiO.sub.2, is too small in proportion to the amount
of either R.sub.2 SiO, R.sub.3 SiO.sub.0.5, or R.sub.2 SiO plus R.sub.3
SiO.sub.0.5, the organopolysiloxane does not take a sufficient degree of
three-dimensional cross-linked structure and is soluble in benzene. This
type of organopolysiloxane cannot be used for the purpose of this
invention, even though it may contain a cross-linked structure. On the
other hand, if the amount of either RSiO.sub.1.5, SiO.sub.2, or
RSiO.sub.1.5 plus SiO.sub.2, is too large in proportion to the amount of
either R.sub.2 SiO, R.sub.3 SiO.sub.0.5, or R.sub.2 SiO plus R.sub.3
SiO.sub.0.5, the cross-linked structure of organopolysiloxane becomes so
hard that it only contains benzene in an amount less than the amount of
organopolysiloxane itself, even though it is insoluble in benzene. This
type of organopolysiloxane cannot be used for the purpose of this
invention, since it separates and is released from an
organopolysiloxane-low-viscosity silicone oil mixture.
The ratio of the R.sub.2 SiO unit to the RSiO.sub.1.5 unit in an
organopolysiloxane polymeric compound which is insoluble in benzene and
may contain an equivalent or more amount of benzene cannot be strictly
specified because of significant involvement of the molecular weight
magnitude of the whole organopolysiloxane polymeric compound, as another
factor. In practice, however, a ratio of 1:1 to 30:1 gave good results. If
the amount of the RSiO.sub.1.5 unit is in a higher side above this ratio,
the organopolysiloxane polymeric compound becomes too hard to contain the
equivalent amount of benzene in it. This type of organopolysiloxane does
not sufficiently swell when it is mixed with a low-viscosity silicone oil.
Silicone oil separates and is released from the mixture. This impairs the
stability of the composition. On the other hand, if the amount of the
R.sub.2 SiO unit is in a higher side above the above-mentioned ratio, the
structural viscosity properties of the organopolysiloxane is lessened.
Because of these reasons, the above-mentioned range of the
organopolysiloxane structural unit ratio is desirable in order to produce
a superior silicone gel composition which is both soft and stable.
An organopolysiloxane polymeric compound, insoluble in benzene and having a
three-dimensional cross-linked structure which may contain benzene in an
equivalent or more amount of the weight of itself, can be prepared by
various methods. Examples of such methods include:
(1) A dehydrogenation-condensation reaction of an
organohydrogenpolysiloxane having at least 2 hydrogen atoms which are
combined with a silicon atom in a molecule. The
dehydrogenation-condensation reaction is carried out in the presence of a
catalytic amount of an alcoholic aqueous solution of an alkali metal
hydroxide and under heating.
(2) A dehydrogenation-condensation reaction of an
organohydrogenpolysiloxane having at least 2 hydrogen atoms which are
combined with a silicon atom in one molecule and an organopolysiloxane
having at least 2 hydroxyl groups which are combined with a silicon atom
in one molecule. This dehydrogenation-condensation reaction is carried out
in the presence of a catalytic amount of an alkali metal hydroxide or a
platinum compound and under heating.
(3) A dehydration-condensation reaction of an organopolysiloxane having at
least 2 hydroxyl groups which are combined with a silicon atom in a
molecule. The dehydration-condensation reaction is carried out in the
presence of a catalytic amount of an alkali metal hydroxide or an
organo-tin compound and under heating.
(4) A dealcohol reaction of an organopolysiloxane having at least 2
hydroxyl groups which are combined with a silicon atom in one molecule and
another organopolysiloxane having at least 2 alkoxy groups which are
combined with a silicon atom in one molecule. The dealcohol reaction is
carried out in the presence of a catalytic amount of an alkali metal
hydroxide or an organo-tin compound and under heating.
All of these methods can easily produce an organopolysiloxane polymeric
compound which is insoluble in benzene and has a three-dimensional
cross-linked structure capable of containing benzene of an equivalent or
more amount of the organopolysiloxane polymeric compound itself.
As another example of a partially cross-linked organopolysiloxane polymeric
compound (C), an organopolysiloxane polymeric compound which is insoluble
but sufficiently swells in silicone oil is given. This organopolysiloxane
polymeric compound is prepared by the addition polymerization of (iii) an
organohydrogenpolysiloxane and (iv) an organopolysiloxane having
unsaturated aliphatic groups, and contains a partial three-dimensional
cross-linked structure.
The organohydrogenpolysiloxane (iii) used in the addition polymerization is
comprised of units HSiO.sub.1.5, RSiO.sub.1.5, RHSiO, R.sub.2 SiO, R.sub.2
HSiO.sub.0.5, R.sub.3 SiO.sub.0.5, and the like. This compound may take
either a linear, branched, or cyclic molecular structure, and contains at
least 2 hydrogen atoms which are combined with a silicon atom in a
molecule. For better control of the reaction producing the
organopolysiloxane polymeric compound, the organohydrogenpolysiloxane used
should have a linear structure. The hydrogen atom bonded to the silicon
atom, i.e., H in --SiH bond, of the organohydrogenpolysiloxane molecule is
usually contained within the molecular chain. It may, however, be at the
molecular chain terminals. A preferable amount of the --SiH bond is
usually 1-20 mol % when the molecular structure is linear or branched, and
1-50 mol % when the molecular structure is cyclic. A preferable
organohydrogenpolysiloxane is that containing 50 mol % or more of a methyl
group of organic groups other than --SiH bond.
The above-mentioned organopolysiloxane (iv) having unsaturated aliphatic
groups which is used in the addition polymerization reaction is that
containing at least 2 unsaturated aliphatic groups which are bonded to a
silicon atom in a molecule. Given as examples of this type of
organopolysiloxane are those containing a vinyl group or an allyl group.
Usually, an organovinylpolysiloxane containing a vinyl group is used. A
specific example of organovinylpoly-siloxane is that containing units
(CH.sub.2 .dbd.CH)SiO.sub.1.5, RSiO.sub.1.5, R(CH.dbd.CH.sub.2)SiO,
R.sub.2 SiO, R.sub.2 (CH.dbd.CH.sub.2)SiO.sub.0.5, R.sub.3 SiO.sub.0.5,
and the like. The molecular structure may be either linear, branched, or
cyclic, and one which contains at least 2 unsaturated aliphatic groups,
e.g. a vinyl group, in one molecule. For better control of the reaction of
producing the organopolysiloxane polymeric compound, an organopolysiloxane
having unsaturated aliphatic groups used should have a linear structure.
This type of organovinylpolysiloxane usually has a linear structure having
dimethylvinylsilyl groups at its both ends of the molecule. The vinyl
group, however, must be within the molecular chain. A preferable amount of
the vinyl group is usually 1-20 mol % when the molecular structure is
linear or branched, and 1- 50 mol % when the molecular structure is
cyclic. A preferable organovinylpolysiloxane is that containing 50 mol %
or more methyl group of organic groups other than a vinyl group.
It is essential for the organohydrogenpolysiloxane (iii) and
organopolysiloxane having unsaturated aliphatic groups (iv), e.g.
organovinylpolysiloxane, to produce an addition polymerization compound
having a three-dimensional structure in part of which these
organopolysiloxanes (iii) and (iv) contain at least 2 reactive groups,
i.e., hydrogen atoms, bonded to a silicon atom or a vinyl group. If the
amount of these reactive groups contained in organopolysiloxanes (iii) or
(iv) is greater than 20 mol %, in the case where organopolysiloxanes have
linear or branched structures, or is greater than 50 mol %, in the case
where organopolysiloxanes have a cyclic structure, the polymers produced
become stiff. In addition, a low-viscosity silicone oil tends to be
encompassed by the three-dimensional structure of such polymers only with
difficulty, and to separate and be released from the mixture, thus
resulting in a less stable product. Conversely, if the content of the
reactive groups is less than 1%, the structural viscosity properties of
the organopolysiloxane tends to be lessened. Because of these reasons,
although not restrictive, the amount of the reactive groups contained in
organopolysiloxanes (iii) or (iv) is 1-20 mol %, in the case where
organopolysiloxanes have linear or branched structures, or 1-50 mol %, in
the case where organopolysiloxanes have a cyclic structure, in order to
produce a superior silicone gel composition which is both soft and stable.
Given as examples of the organic group R in the constituting unit of the
above organohydrogenpolysiloxane (iii) are an alkyl group such as methyl,
ethyl, propyl, butyl, or the like, an aryl group such as phenyl, tolyl, or
the like, or cyclohexyl group. R may also be a substituted mono-valent
hydrocarbon group, other than unsaturated aliphatic hydrocarbon groups
such as a vinyl group. The substitution group may be a halogen atom, cyano
group or the like.
A typical example of such an organohydrogenpolysiloxane is a
methylhydrogenpolysiloxane containing units (CH.sub.3).sub.3 SiO--,
--[(CH.sub.3).sub.2 SiO].sub.p --, --[(CH.sub.3)HSiO].sub.q --, and
--Si(CH.sub.3) .sub.3, wherein p is a value of 10-500 and q is a value of
2-50.
The organic group R contained in organovinylpolysiloxane, which is an
organopolysiloxane having unsaturated aliphatic groups (iv), has the same
meaning as the R for organohydrogenpolysiloxanes. A typical example of
such an organovinylpolysiloxane is that containing units (CH.sub.2
.dbd.CH)(CH.sub.3).sub.2 SiO--, --[(CH.sub.3).sub.2 SiO].sub.r --, and
--Si(CH.sub.3).sub.2 (CH.dbd.CH.sub.2), wherein r is a value of 10-100, or
that containing units (CH.sub.3).sub.3 SiO--, --[(CH.sub.3).sub.2
SiO].sub.m --, --[(CH.dbd.CH.sub.2)(CH.sub.3)SiO].sub.n --, and
--Si(CH.sub.3).sub.3, wherein m is a value of 10-500 and n is a value of
2-50. These organovinylpolysiloxanes are suitable materials and may be
used either individually or as a mixture.
The addition polymerization reaction of the organohydrogenpolysiloxane
(iii) and organopolysiloxane having unsaturated aliphatic groups (iv) can
be carried out according to a commonly known method. For example, a target
organopolysiloxane polymeric compound which is insoluble in a silicone oil
can be easily prepared by reacting an organohydrogenpolysiloxane and an
organovinylpolysiloxane, at a proportion such that the molar ratio of the
.tbd.SiH group and vinyl group is in the range of 1:3-3:1, under heating
while stirring in the presence of a platinum or palladium addition
polymerization catalyst. An especially preferable addition polymerization
catalyst is chloroplatinic acid described in Japanese Patent Publication
No. 9969/1958.
It is desirable that the partially cross-linked organopolysiloxane
polymeric compound (C) be incorporated in an amount of 0.2-40% by weight
of the gel composition. The intended effect cannot be obtained if the
amount is less than 0.2% by weight. If the amount exceeds 40% by weight,
on the other hand, the gel composition becomes too soft to maintain a
solid state. This also applies to the cosmetic composition to which the
gel is incorporated.
Such a gel composition can be prepared by simply blending the
acryl-silicone graft copolymer, the low-viscosity silicone oil, and the
partially cross-linked organopolysiloxane polymeric compound. An
alternative method is to prepare a gel composition from the acryl-silicone
graft copolymer and the low-viscosity silicone oil, and a gel composition
from the partially cross-linked organopolysiloxane polymeric compound and
the low-viscosity silicone oil, followed by blending the two gel
compositions. This latter method can produce a gel composition having
different characteristics from that produced by blending the three
components at the same time. Specifically, such a gel composition can
contain a greater amount of silicone oil in a more stable manner. This
provides the resulting cosmetic composition with superior smoothness and
freshness as well as even better stability over time.
The gel composition which has been fully discussed above is incorporated in
an amount of 30-100% by weight based on the total weight of the cosmetic
composition.
The cosmetic composition of the present invention can be used as makeup
cosmetics such as eyeshadows, foundations, face powders, rouges,
lipsticks, eyeliners, mascaras, and the like, hair cosmetics, as well as
basic cosmetics such as eyestick and the like.
Among the above essential components, the acryl-silicone graft copolymer
(A) has an excellent film-forming capability. Thus, the cosmetic
composition to which this component is incorporated can produce a film
exhibiting a superior water-resistance, oil-resistance, and other
characteristics required for cosmetic films. Taking a cosmetic composition
for application to nails such as a nail enamel as an example, such a
cosmetic composition can be prepared by dissolving the copolymer (A) into
a low-boiling-point oil (D) or a volatile solvent (E). The cosmetic
composition thus prepared can produce a continuous film immediately upon
application. The low-boiling-point oil (D) used here includes volatile
hydrocarbon oils having a boiling point below 260.degree. C. at normal
pressure. There are no special limitations as to the types of
hydrocarbons. Any types usually used for cosmetics can be used. Specific
examples include IP Solvent (trade mark; manufactured by Idemitsu
Petrochemical Co., Ltd.), Shellsol (trade mark; manufactured by Shell
Chemical Co., Ltd.), Isoper (trade mark; manufactured by Esso Chemical
Co.), and the like. Another type of low-boiling-point oil (D) is a
volatile, linear or cyclic silicone oil having a boiling point below
260.degree. C. at normal pressure and a viscosity below 2 cs, such as
dimethylpolysiloxane of a low polymerization degree,
octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, and the like.
Examples of a volatile solvent (E) include ethyl acetate, butyl acetate,
acetone, toluene, and the like. The amount of copolymer (A) to be
incorporated into the cosmetic composition is usually 10-70% by weight,
and preferably 30-60% by weight. The film produced by the cosmetic
composition becomes so thin that the intended effect cannot be exhibited
if the amount of copolymer (A) is too small. Too much inclusion of the
copolymer (A), on the other hand, results in a high-viscosity product
which is hard to apply to nails. Characteristics of films produced by
conventional cosmetics are controlled by the addition of camphor, phthalic
acid derivative, or alkid resin. In the cosmetic composition of the
present invention, however, such characteristics can be controlled by
adjusting the acrylic chain composition or silicone chain length
distribution in the copolymer (A). For example, a hard film can be
produced by introducing a large amount of methylmethacrylate into acrylic
chains, while a soft film that is more soluble in a solvent can be
produced by using a greater amount of butylacrylate or
2-ethyl-hexylacrylate. A smooth, slippery film is obtained when a
long-chain silicone is used.
A non-aqueous-type makeup cosmetic such as eyeliner, mascara, or the like
can be produced by dissolving the copolymer (A) into the aforementioned
volatile hydrocarbon oil or volatile silicone oil. The volatile component
evaporates when this type of makeup cosmetic is applied to the object,
thereby producing a continuous film. The amount of copolymer (A]to be
incorporated into such a makeup cosmetic composition is usually 5-60% by
weight, and preferably 10-40% by weight. Since a continuous film cannot be
produced, the intended effect cannot be adequately exhibited if the amount
of copolymer (A) is too small, although this will depend on other
components such as waxes or pigments. If the amount of the copolymer (A)
is too large, the viscosity becomes so high that the usability of the
product is impaired. In addition the film gets so hard that it is
difficult to remove it using a removing agent. When the product is an
eyeliner, the removing operation will damage the area around the eye.
Another makeup cosmetic composition produced from the acryl-silicone graft
copolymer (A) of the present invention is that comprising, in addition to
the copolymer (A), a low-boiling-point oil (D), a cosmetic powder material
(F), and a polyacrylic emulsion of the type increasing its viscosity under
alkaline conditions (G). Such a makeup cosmetic composition produces a
uniform film which possesses improved water-resistance, oil-resistance,
and adhesiveness. It gives a good sensation upon use and exhibits a
prolonged makeup effect. Superior stability over time can be achieved
without necessarily using an emulsifier.
It is desirable that the copolymer (A) be incorporated into the makeup
cosmetic composition of the present invention in an amount of 5-20% by
weight. The effect of the present invention cannot be obtained if the
amount is smaller than 5% by weight. If the amount exceeds 20% by weight,
the resulting makeup cosmetic composition has a high viscosity. This makes
it uneasy to apply the makeup cosmetic composition and produces a
thick-film sensation after the application.
The aforementioned volatile hydrocarbons or silicone oils having a boiling
point below 260.degree. C. at normal pressure can be used as the
low-boiling-point oil (D). They can be used either independently or as a
mixture. Their amount in the makeup cosmetic composition is 5-30% by
weight, and preferably 7-20% by weight. The low-boiling-point oil (D)
functions as a solvent of the copolymer (A). It also plays a very
important role in promoting the life of the cosmetic film.
There are no specific limitations as to the cosmetic powder material (F)
used in the makeup cosmetic composition. It may be a body pigment,
inorganic white pigment, inorganic colored pigment, organic pigment,
organic powder, pearling agent, or the like. Specific examples are talc,
mica, magnesium carbonate, calcium carbonate, magnesium silicate, aluminum
magnesium silicate, silica, titanium dioxide, zinc oxide, red iron oxide,
yellow iron oxide, black iron oxide, ultramarine blue, tar pigment, nylon
powder, polyethylene powder, methylacrylate powder, polystyrene powder,
polytetrafluoroethylene powder, silk powder, crystalline cellulose,
starch, titanated mica, iron oxide titanated mica, bismuth oxychloride,
and the like. These cosmetic powders may be used after a surface-treatment
with an oily agent such as silicone or the like. They can be used
independently, or two or more of them can be used in combination.
The amount of the cosmetic powder material used for the makeup cosmetic
composition can be determined depending on the intended use or purpose
without limitation. Usually, an amount of 5-40% by weight is preferable.
Examples given as a polyacrylic emulsion of the type increasing its
viscosity under alkaline conditions, which is the component (G), are
homopolymers of acrylic acid or methacrylic acid, their copolymers, and
partially cross-linked acrylic acid polymers. They increase their
viscosities when neutralized with an alkali. These component (G) emulsions
may be used independently, or two or more of them can be used in
combination. The amount of the component (G) to be incorporated in the
cosmetic composition of the present invention is 1-10% by weight. Within
this range, the component (G) can homogeneously disperse the solution of
the acryl-silicone graft copolymer (A) in the low-boiling-point oil (D) in
an aqueous phase. If the amount is less than 1% by weight, the dispersion
can be achieved only insufficiently, resulting a product having an
inadequate viscosity. If the amount is greater than 10% by weight, on the
other hand, the product becomes too viscous to be conveniently applied.
Any alkaline substance commonly used for cosmetics can be used to
neutralize the polyacrylic emulsion and to raise its viscosity. Given as
examples of alkalis which can be suitably used are inorganic alkalis such
as sodium hydroxide and potassium hydroxide, basic amino acids such as
L-arginine, amines such as triethanolamine, and ammonia, and the like. The
amount of alkali used in the cosmetic composition is determined taking
into account the type of the alkali and the type of polyacrylic emulsion
which are used for preparing the cosmetic composition. Usually, a
preferable amount is 0.03-2.5% by weight. The alkali is added, for
example, by dissolving it in water in advance, or by directly mixing it
with the polyacrylic emulsion. The method of the addition of an alkali,
however, is not limited by these.
Furthermore, an o/w-type emulsion cosmetic composition can be prepared by
using the copolymer (A) and the low-boiling-point oil (D) at a specific
proportion. This o/w-type emulsion cosmetic composition exhibits a smooth
spreadability on the skin without imparting an oily sensation, and yet,
upon application, produces a film having excellent water-repellency. It
also possesses good stability over time.
This o/w-type emulsion cosmetic composition comprises 10-40% by weight of
an oily component mixture which comprises 2-40% by weight of the copolymer
(A) and 20-60% by weight of the low-boiling-point oil (D), wherein the
amount of components (A) plus (D) in the total oily component mixture is
60-100% by weight. The copolymer (A) plays an important role in the high
water-repellency possessed by the o/w-type emulsion cosmetic composition.
The amount of this copolymer in the oily component mixture is in the range
of 2-40% by weight. An amount of less than 2% by weight does not produce a
sufficient water-repelling characteristic in the emulsion cosmetic
composition. An amount exceeding 40% by weight of the copolymer in the
mixture raises the viscosity of the resulting emulsion cosmetic
composition. This affects the readiness in the application of the emulsion
cosmetic composition to the skin and imparts an oily feeling to the skin.
The aforementioned low-boiling-point oils can be used as the component (D)
| | |
