JP2002249588A - Emulsion, and its production process - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a process for efficiently producing an emulsion which has good capability of being incorporated into a cosmetic and the like, and gives a blended material, such as a cosmetic, having good dispersion of an oil and crosslinked silicone particles therein. SOLUTION: The emulsion comprises oil liquid droplets having a mean particle diameter of 0.5-500 μm, emulsified in an aqueous solution of a surfactant, and containing crosslinked silicone particles having a mean diameter of 0.1-100 μm, wherein the surfactant is an amphoteric surfactant. The process for producing the emulsion is characterized in that a crosslinkable silicone composition containing a non-crosslinkable oil is subjected to a crosslinking reaction in a state in which the composition is emulsified in an aqueous solution of the surfactant.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an emulsion containing crosslinked silicone particles in oil droplets emulsified in an aqueous surfactant solution, and a method for producing the same. And the dispersibility of the oil and the cross-linked silicone particles in the cosmetic and the like is good, and the effects of the oil and the cross-linked silicone particles are sufficiently mixed. The present invention relates to an emulsion that can be exhibited, and a method for efficiently producing such an emulsion.

[0002]

2. Description of the Related Art JP-A-2000-281903 and JP-A-2000-281523 propose emulsions containing crosslinked silicone particles in oil droplets emulsified in an aqueous surfactant solution. In particular,
JP-A-2000-281523 describes that such an emulsion allows oil and crosslinked silicone particles to be uniformly dispersed in cosmetics. Examples of the surfactant in this emulsion include nonionic, anionic, and cationic surfactants.
In particular, it is described that non-ionic ones are preferable.

[0003] However, such emulsions are not sufficiently satisfactory in the incorporation into cosmetics and the dispersibility of oil and crosslinked silicone particles in the obtained cosmetics. There is a problem that the effect cannot be sufficiently exhibited.

[0004]

SUMMARY OF THE INVENTION The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, have found that emulsions containing crosslinked silicone particles in oil droplets emulsified in an aqueous surfactant solution. In the above, the present inventors have found that the above-mentioned problems can be solved by using a zwitterionic surfactant as the surfactant, and arrived at the present invention.

That is, an object of the present invention is to provide an emulsion containing crosslinked silicone particles in oil droplets emulsified in an aqueous solution of a surfactant, which can be blended into cosmetics and the like, and obtained. An emulsion in which the dispersibility of oil and cross-linked silicone particles in a composition such as cosmetics is good, and the effect of blending the oil and cross-linked silicone particles can be sufficiently exhibited, and a method for efficiently producing such an emulsion Is to provide.

[0006]

The emulsion of the present invention has an average particle size of 0.5 emulsified in an aqueous surfactant solution.
The average particle size is 0.1 to 10
An emulsion containing 0 μm crosslinked silicone particles (where the particle size of the crosslinked silicone particles is smaller than the particle size of the oil droplets), wherein the surfactant is zwitterionic. And

Further, the method for producing an emulsion of the present invention relates to a method for preparing a crosslinkable silicone composition containing a non-crosslinkable oil (however, the content of the non-crosslinkable oil is determined by the fact that the crosslinked product of the crosslinkable silicone composition is An amount exceeding the amount capable of holding oil.) Is subjected to a cross-linking reaction in an aqueous surfactant solution in an emulsified state, whereby an oil droplet having an average particle size of 0.5 to 500 μm has an average particle size of 0.1 to 500 μm. A method for producing an emulsion containing 100 μm crosslinked silicone particles (where the particle size of the crosslinked silicone particles is smaller than the particle size of the oil droplets), wherein the surfactant is zwitterionic. There is a feature.

[0008]

First, the emulsion of the present invention will be described in detail. This emulsion is an emulsion containing crosslinked silicone particles in oil droplets emulsified in an aqueous solution of a surfactant, wherein the surfactant is zwitterionic. The average particle size of the crosslinked silicone particles is in the range of 0.1 to 100 μm, preferably in the range of 0.1 to 50 μm, and particularly preferably in the range of 0.5 to 50 μm.
This is because it is difficult to prepare crosslinked silicone particles having an average particle size less than the lower limit of the above range, while crosslinked silicone particles exceeding the upper limit of the above range have a low compoundability in cosmetics and the like. This is because there is a possibility that the dispersibility in the composition such as the obtained cosmetic or the like may be reduced. However, the particle size of the crosslinked silicone particles is smaller than the particle size of the oil droplets. The properties of the crosslinked silicone particles are not limited, but are preferably in the form of an elastomer such as a rubber or a gel. The shape of the crosslinked silicone particles is not limited, and examples thereof include a spherical shape, a spindle shape, a flat shape, and an irregular shape, and a spherical shape is particularly preferable.

The crosslinked silicone particles are obtained by crosslinking a crosslinkable silicone composition, and include, for example, those which are crosslinked by a hydrosilylation reaction, those which are crosslinked by a condensation reaction, those which are crosslinked by an organic peroxide, Examples include those crosslinked by energy rays, and preferably crosslinked by a hydrosilylation reaction or a condensation reaction.

The oil droplets containing the above-mentioned crosslinked silicone particles have an average particle size in the range of 0.1 to 500 μm, preferably in the range of 0.1 to 200 μm, and particularly preferably in the range of 0.1 to 200 μm. It is in the range of 0.5 to 200 μm. This is because it is difficult to prepare an emulsion in which the average particle size of the oil droplets is less than the lower limit of the above range, whereas an emulsion exceeding the upper limit of the above range tends to have reduced stability. It is. The viscosity of this oil at 25 ° C. is not limited, but is preferably 1 to
It is within the range of 100,000,000 mPa · s, more preferably within the range of 1 to 10,000,000 mPa · s, and particularly preferably within the range of 1 to 1,000,000 mPa · s. Such oils include, for example, silicone oils and organic oils, and are preferably silicone oils because of their excellent affinity with crosslinked silicone particles.

[0011] As the silicone oil, linear,
Examples thereof include those having a molecular structure such as a linear, cyclic, or branched chain partially having a branch, and particularly preferably those having a linear or cyclic molecular structure. Further, it is preferable that the silicone oil does not participate in a crosslinking reaction when forming the crosslinked silicone particles. When the cross-linking reaction is a hydrosilylation reaction, the silicone oil does not have an alkenyl group or a silicon-bonded hydrogen atom in the molecule. Methylphenylpolysiloxane blocked with trimethylsiloxy groups at both ends of chain, dimethylsiloxane / methylphenylsiloxane copolymer blocked with trimethylsiloxy groups at both ends of molecular chain, dimethylsiloxane methyl (3,3,3-triblock) (Fluoropropyl) siloxane copolymer, cyclic dimethylsiloxane, and cyclic methylphenylsiloxane. When the crosslinking reaction is a condensation reaction, the silicone oil does not have a silanol group, a silicon-bonded hydrogen atom, or a silicon-bonded hydrolyzable group in the molecule. In addition, for example, dimethylpolysiloxane blocked with dimethylvinylsiloxy groups at both ends of molecular chains, dimethylsiloxane / methylvinylsiloxane copolymer with blocked dimethylvinylsiloxy groups at both ends of molecular chains, methylvinylpolysiloxane blocked with trimethylsiloxy groups at both ends of molecular chains, Cyclic methyl vinyl siloxane;

Examples of the organic oil include, for example, isoparaffin, hexyl laurate, isopropyl myristate, myristyl myristate, cetyl myristate, 2-octyldodecyl myristate, isopropyl palmitate, 2-ethylhexyl palmitate, butyl stearate. , Decyl oleate, 2-octyldodecyl oleate, myristyl lactate, cetyl lactate, lanolin acetate, stearyl alcohol, cetostearyl alcohol, oleyl alcohol, avocado oil, almond oil, olive oil, cacao oil, jojoba oil, sesame oil, safflower Oil, soybean oil, camellia oil, squalane, persic oil,
Castor oil, mink oil, cottonseed oil, coconut oil, egg yolk oil, tallow,
Examples include lard, polypropylene glycol monooleate, neopentyl glycol-2-ethylhexanoate, isostearic acid triglyceride, coconut oil fatty acid triglyceride, polyoxyethylene lauryl ether, and polyoxypropylene cetyl ether.

The amphoteric surfactant is a characteristic component of the present emulsion, and the compoundability of this emulsion in cosmetics and the like, and the dispersion of oil and crosslinked silicone particles in the resulting cosmetics and other compounds. It is a component for improving the properties. This amphoteric surfactant contains an alkyl group having 11 to 17 carbon atoms because it has good emulsion stability and can sufficiently emulsify a crosslinkable silicone composition in the emulsion production method described below. It is particularly preferable that the carbon number is 11
It is preferable that the compound contains from 15 to 15 alkyl groups. Examples of such amphoteric surfactants include betaine type such as betaine, sulfobetaine, sulfate betaine and imidazolinium betaine; phospholipid type such as lecithin; amino acid type; and amine oxide type. In particular, it is preferably a betaine type.

Such betaine-type zwitterionic surfactants include, for example, those represented by the following general formula:

Embedded image N, N-dimethyl-N-alkyl-N-carboxymethylammonium betaine represented by the general formula:

Embedded image N, N, N-trialkyl-N-sulfoalkylene ammonium betaine represented by the general formula:

Embedded image A fatty acid amidopropyldimethyl acetate betaine represented by the general formula:

Embedded image 2-alkyl-1-carboxymethyl-1- represented by
Hydroxyethyl imidazolinium betaine. Note that R in the above formula is an alkyl group having 11 to 17 carbon atoms, preferably an alkyl group having 11 to 15 carbon atoms. Further, R ′ in the above formula is an alkyl group having 17 or less carbon atoms, preferably an alkyl group having 15 or less carbon atoms. In the above formula, R ″ is an alkyl group having 17 or less carbon atoms, preferably an alkyl group having 15 or less carbon atoms, and n in the above formula is an integer of 1 or more. Examples of the ionic surfactant include Amphitol (20 BS, 20 N, 20 AB, 24 B, 5
5AB, 20HD), Lebon (2000L, 2000HG, LD-36, 101-) of Sanyo Chemical Industry Co., Ltd.
H), view light (LCA, LCA-30D, EC)
A, LCA-H, A-5000, ESS) and AM-301 of Nippon Surfactant Industries, Ltd.

The present emulsion comprises at least oil droplets containing crosslinked silicone particles, a zwitterionic surfactant and water, but the content of these is not limited, but the content of the zwitterionic surfactant is not limited. Is preferably in the range of 0.001 to 20% by weight in this emulsion, and particularly preferably in the range of 0.01 to 10% by weight. This is because if the content of the amphoteric surfactant is less than the lower limit of the above range, the compoundability of the emulsion in cosmetics or the like may be reduced, or the oil and the crosslinking in the resulting cosmetics or other compounds may be reduced. This is because the dispersibility of the silicone particles may be reduced, and on the other hand, if the upper limit of the above range is exceeded, the use of the emulsion may be limited. Further, the content of water is preferably in the range of 5 to 99% by weight in the emulsion,
In particular, the content is preferably in the range of 10 to 80% by weight.

Next, the method for producing the emulsion of the present invention will be described in detail. The method for producing the emulsion of the present invention comprises:
A method for producing the above emulsion by subjecting a cross-linkable silicone composition containing a non-cross-linkable oil to a cross-linking reaction in an aqueous surfactant solution in an emulsified state, wherein the surfactant is zwitterionic. It is characterized by being. Examples of the crosslinkable silicone composition include those which are crosslinked by a hydrosilylation reaction, those which are crosslinked by a condensation reaction, those which are crosslinked by an organic peroxide, and those which are crosslinked by a high energy ray. It is preferable that the resin be crosslinked by a reaction or a condensation reaction.

Examples of the crosslinkable silicone composition which is crosslinked by the hydrosilylation reaction include an organopolysiloxane having at least two alkenyl groups in one molecule, and at least two silicon-bonded hydrogen atoms in one molecule. And at least an organopolysiloxane and a catalyst for hydrosilylation reaction.

Examples of the alkenyl group in the former organopolysiloxane include a vinyl group, an allyl group, a butenyl group, a pentenyl group and a hexenyl group, and a vinyl group is preferred. Examples of the group bonded to a silicon atom other than the alkenyl group in the organopolysiloxane include a methyl group, an ethyl group, a propyl group,
Alkyl groups such as butyl group; cycloalkyl groups such as cyclopentyl group and cyclohexyl group; aryl groups such as phenyl group, tolyl group and xylyl group; aralkyl groups such as benzyl group, phenethyl group and 3-phenylpropyl group;
Examples include a monovalent hydrocarbon group such as a halogenated hydrocarbon group such as a chloropropyl group and a 3,3,3-trifluoropropyl group. Examples of the molecular structure of the organopolysiloxane include linear, cyclic, network, and partially branched linear chains. In order to form elastomeric crosslinked silicone particles, linear or partially branched It is preferred that the compound is linear. The viscosity of the organopolysiloxane at 25 ° C. is not limited, but is preferably in the range of 10 to 100,000 mPa · s, and particularly preferably in the range of 10 to 10,000 mPa · s.

The group bonded to a silicon atom other than a hydrogen atom in the latter organopolysiloxane includes:
The same monovalent hydrocarbon groups as described above are exemplified. Examples of the molecular structure of the organopolysiloxane include linear, cyclic, network, and partially branched linear structures. The viscosity of the organopolysiloxane at 25 ° C. is not limited, but is preferably 1 to 10,000 m 2.
It is within the range of Pa · s. The content of the organopolysiloxane may be an amount sufficient to crosslink the composition, and for example, may be within the range of 0.1 to 200 parts by weight based on 100 parts by weight of the former organopolysiloxane. preferable.

The hydrosilylation reaction catalyst is a catalyst for accelerating the crosslinking reaction of the above composition.
Platinum-based catalysts, rhodium-based catalysts, and palladium-based catalysts are exemplified, and platinum-based catalysts are preferred. Examples of the platinum-based catalyst include chloroplatinic acid, an alcohol solution of chloroplatinic acid, an olefin complex of platinum, an alkenylsiloxane complex of platinum, platinum black, and platinum-supported silica. The content of the hydrosilylation reaction catalyst may be an amount sufficient to promote the crosslinking reaction of the above composition.For example, the metal atom in the present catalyst is 0.1 part by weight relative to the crosslinkable silicone composition. Preferably it is in the range of 1 to 1,000 ppm.

Examples of the crosslinkable silicone composition which is crosslinked by a condensation reaction include, for example, an alkoxy group, an oxime group, an acetoxy group, an aminoxy group and the like bonded to at least two silanol groups or silicon atoms in one molecule. An organopolysiloxane having a decomposable group, a silane or siloxane having a hydrolyzable group such as an alkoxy group, an oxime group, an acetoxy group, or an aminoxy group bonded to at least three silicon atoms in one molecule, and an organotin compound; Examples include those comprising at least a condensation reaction catalyst such as an organic titanium compound.

Examples of the alkoxy group in the organopolysiloxane include a methoxy group, an ethoxy group, and a methoxyethoxy group. In addition, examples of the oxime group in the organopolysiloxane include a dimethyl ketoxime group and a methyl ethyl ketoxime group. Examples of the group bonded to the other silicon atom in the organopolysiloxane include an alkyl group such as a methyl group, an ethyl group, a propyl group and a butyl group; a cycloalkyl group such as a cyclopentyl group and a cyclohexyl group; , Allyl, butenyl, pentenyl, hexenyl; aryl such as phenyl, tolyl, xylyl; aralkyl such as benzyl, phenethyl, 3-phenylpropyl; 3-chloropropyl, 3, Three,
Examples include a monovalent hydrocarbon group such as a halogenated hydrocarbon group such as a 3-trifluoropropyl group. As the molecular structure of the organopolysiloxane, for example, linear, cyclic,
Examples thereof include a network and a partially branched straight chain. In order to form an elastomeric crosslinked silicone particle, it is preferably a straight chain or a partially branched straight chain.
The viscosity of the organopolysiloxane at 25 ° C. is not limited, but is preferably from 10 to 100,000 m
Pa · s, particularly preferably 10 to 10,000.
Within the range of 0 mPa · s.

The alkoxy and oxime groups in the silane or siloxane are the same as those described above. Examples of such a silane or siloxane include methyltrimethoxysilane, vinyltrimethoxysilane, methyltrioximesilane, vinyltrioximesilane, methylpolysilicate, and ethylpolysilicate. The content of the silane or siloxane may be an amount sufficient to crosslink the composition, and for example, may be within the range of 0.1 to 200 parts by weight based on 100 parts by weight of the organopolysiloxane. preferable.

The catalyst for the condensation reaction of an organotin compound, an organotitanium compound or the like is a catalyst for accelerating the crosslinking reaction of the above-mentioned composition, for example, dibutyltin dilaurate,
Dibutyltin diacetate, tin octenoate, dibutyltin dioctate, tin laurate, tetrabutyl titanate,
Examples include tetrapropyl titanate and dibutoxybis (ethyl acetoacetate). The content of the condensation reaction catalyst may be an amount sufficient to cause a crosslinking reaction of the composition, and may be in the range of 0.01 to 10 parts by weight based on 100 parts by weight of the organopolysiloxane. Preferably, it is particularly preferably in the range of 0.05 to 5 parts by weight.

Further, such a crosslinkable silicone composition may contain a filler as an optional component for adjusting the fluidity of the composition or improving the mechanical strength of the obtained crosslinked silicone particles. Examples of the filler include reinforcing fillers such as precipitated silica, fumed silica, calcined silica, and fumed titanium oxide; unreinforced fillers such as ground quartz, diatomaceous earth, aluminosilicate, iron oxide, zinc oxide, calcium carbonate, and the like. And a filler obtained by treating the surface of these with an organosilicon compound such as hexamethyldisilazane, trimethylchlorosilane, polydimethylsiloxane, or polymethylhydrogensiloxane.

Such a crosslinkable silicone composition is characterized by containing a non-crosslinkable oil. Examples of the oil include a silicone oil and an organic oil, and a silicone oil is preferable because of its excellent affinity with crosslinked silicone particles.

Examples of the silicone oil include those having the same molecular structure as described above, and particularly preferably those having a linear or cyclic molecular structure. When the crosslinkable silicone composition is crosslinked by a hydrosilylation reaction, the silicone oil does not have an alkenyl group or a silicon-bonded hydrogen atom in the molecule, and examples thereof are the same as those described above. When the crosslinkable silicone composition is crosslinked by a condensation reaction, the silicone oil does not have a silanol group, a silicon-bonded hydrogen atom, or a silicon-bonded hydrolyzable group in the molecule. Similar ones are exemplified.
Examples of the organic oil include the same as those described above.

In the crosslinkable silicone composition, the content of the oil is determined so that the crosslinked product of the crosslinkable silicone composition can retain the oil in the crosslinked product (that is, the crosslinked product can contain the oil). (The amount of oil). The amount that can be held is
Although it depends on the combination of the crosslinkable silicone composition and the noncrosslinkable oil, the content of the noncrosslinkable oil is generally 2 parts per 100 parts by weight of the crosslinkable silicone composition.
It is preferably in the range of 00 to 5,000 parts by weight, and particularly preferably in the range of 250 to 2,000 parts by weight.

The production method of the present invention is characterized in that a crosslinkable silicone composition containing such a non-crosslinkable oil is crosslinked in an amphoteric surfactant aqueous solution in an emulsified state. This amphoteric surfactant is a characteristic component of the production method of the present invention, and the compoundability of the obtained emulsion with cosmetics and the like, and the presence of oil and crosslinked silicone particles in the composition of the obtained cosmetics and the like. It is a component for improving the dispersibility of the. The amphoteric surfactant preferably contains an alkyl group having 11 to 17 carbon atoms, since it can sufficiently emulsify the crosslinkable silicone composition, and particularly preferably has an alkyl group having 11 to 15 carbon atoms. Is preferable. Examples of such amphoteric surfactants include betaine type such as betaine, sulfobetaine, sulfate betaine and imidazolinium betaine; phospholipid type such as lecithin; amino acid type; and amine oxide type. ,In particular,
It is preferably of the betaine type. Examples of the betaine-type zwitterionic surfactant are the same as described above.

In order to emulsify the crosslinkable silicone composition in an amphoteric surfactant aqueous solution, for example, a homomixer, paddle mixer, Henschel mixer, homodisper, colloid mixer, propeller stirrer, homodisper, homogenizer, in-line continuous Emulsifiers such as an emulsifier, an ultrasonic emulsifier, and a vacuum kneader can be used.

In the production method of the present invention, the above-mentioned crosslinkable silicone composition may be emulsified in an amphoteric surfactant aqueous solution at a time, or the crosslinkable silicone composition excluding the catalyst may be emulsified. After emulsification in an amphoteric surfactant aqueous solution, a catalyst may be added. In this case, it is preferable to add the catalyst by emulsifying it with a surfactant. In this case, the surfactant that can be used is a nonionic, cationic, anionic, or zwitterionic. And an amphoteric one is particularly preferred.

In the production method of the present invention, the amount of water to be added is not limited, but is preferably in the range of 5 to 99% by weight in the obtained emulsion, and particularly preferably 10 to 8% by weight.
It is preferably in the range of 0% by weight. The amount of the amphoteric surfactant is not limited, but is preferably in the range of 0.1 to 20 parts by weight based on 100 parts by weight of the crosslinkable silicone composition containing the non-crosslinkable oil. In particular, it is preferably in the range of 0.2 to 10 parts by weight.

By heating the emulsion of the crosslinkable silicone composition thus prepared, leaving it at room temperature, or irradiating it with a high energy ray,
The crosslinkable silicone composition dispersed in water can be crosslinked.

The emulsion of the present invention is an emulsion containing crosslinked silicone particles in oil droplets emulsified in an aqueous solution of a surfactant, and has good mixability with cosmetics and the like, and the resulting cosmetics. It is useful as a raw material for aqueous cosmetics because the dispersibility of the oil and the crosslinked silicone particles in the composition such as the above is good, and the effect of the blending of the oil and the crosslinked silicone particles can be sufficiently exerted. Also,
The oil composition obtained by removing water from such an emulsion is in the form of a liquid, paste, cream, or grease, and the crosslinked silicone particles are uniformly dispersed in the oil. When combined with
The oil and the crosslinked silicone particles can be uniformly dispersed in the obtained cosmetic.

[0035]

EXAMPLES The emulsion of the present invention and the method for producing the emulsion will be described in detail with reference to examples. In addition, the viscosity in an Example is a value measured at 25 degreeC. The average particle size of the emulsion, the average particle size of the crosslinked silicone particles, and the characteristics of the oil composition were determined as follows. [Average particle size of emulsion] A laser diffraction particle size distribution analyzer (LA-5 manufactured by Horiba, Ltd.)
00), and the obtained median diameter (particle diameter corresponding to 50% of the cumulative distribution, 50% particle diameter) was defined as the average particle diameter. [Emulsion stability]
It was sealed in a 0 ml glass bottle (depth: 105 mm, diameter: 50 mm) and left at room temperature for 1 week. After standing, the thickness of the aqueous layer separated from the emulsion was measured. [Dispersibility of Crosslinked Silicone Particles] The emulsion was air-dried on a glass plate, and the shape, aggregation state, and distribution of the crosslinked silicone particles were observed under an optical microscope. If all cross-linked silicone particles are dispersed as primary particles, "○" indicates that aggregated particles of several hundreds
If there was a secondary particle, it was evaluated as "x". [Average Particle Size of Crosslinked Silicone Particles] The emulsion was air-dried on a glass plate, and the silicone particles were observed with an optical microscope to determine the average particle size of 10 particles. [Viscoelasticity of Oil Composition] An oil composition was prepared by collecting 10 g of an emulsion in an aluminum dish having a diameter of 5 cm and air-drying in a fume hood for four days and nights to remove water. The storage modulus G ′ (× 10 ³ dyne / cm ² ) and the loss modulus G ″ of this oil composition
(× 10 ³ dyne / cm ² ) and the loss tangent tan δ were measured using an ARES viscoelasticity measuring device (Reometric Scientific).
c). The measurement conditions were room temperature,
25mm parallel plate, gap: 0.5-0.6mm,
Strain: 10%, frequency: 0.1 to 50 rad / s.

[Example 1] 18.8 parts by weight of a dimethylsiloxane-methylvinylsiloxane copolymer having an average of 4.2 vinyl groups per molecule and having a viscosity of 350 mPa · s and a dimethylvinylsiloxy group at both ends of a molecular chain blocked. Having a content of silicon-bonded hydrogen atoms of about 0.5% by weight and a viscosity of 45 m
Equivalent to 1.2 parts by weight of a dimethylsiloxane / methylhydrogensiloxane copolymer having both ends of a trimethylsiloxy group having a Pa · s molecular chain and 80 parts by weight of a dimethylpolysiloxane having a trimethylsiloxy group having both ends of a molecular chain having a viscosity of 100 mPa · s. After mixing into a colloid mill, the formula:

Embedded image 26 of betaine lauryl dimethylaminoacetate represented by
The emulsion was emulsified in an aqueous solution consisting of 3.8 parts by weight of a 3.8% by weight aqueous solution and 47.2 parts by weight of pure water to prepare an emulsion of the silicone composition.

Next, a platinum-based catalyst containing a 1,3-divinyltetramethoxydisiloxane complex of platinum as a main component was emulsified with the above-mentioned aqueous solution of betaine lauryldimethylaminoacetate in an emulsion of the silicone composition. Emulsion (average particle size of platinum catalyst = 0.3μ)
m, platinum metal concentration = 0.05% by weight) to the silicone composition in an amount such that platinum metal becomes 20 ppm by weight, and uniformly mixed, and then allowed to stand at room temperature for 1 day to obtain a silicone composition. Was crosslinked by a hydrosilylation reaction to prepare an emulsion having crosslinked silicone particles in silicone oil droplets dispersed in water.

The emulsion was transferred to an aluminum dish having a diameter of 5 cm and air-dried in a fume hood for one week to remove water, thereby preparing a silicone oil composition having crosslinked silicone particles. This silicone oil composition was creamy. Observation of the silicone oil composition with an optical microscope showed that the crosslinked silicone particles were uniformly dispersed in the silicone oil, and that the shape of the crosslinked silicone particles was spherical.

Example 2 In Example 1, the viscosity was 10
Dispersed in water in the same manner as in Example 1 except that a dimethylpolysiloxane having a molecular chain at both ends of trimethylsiloxy group having a viscosity of 10 mPa · s was used instead of the dimethylpolysiloxane having a molecular chain at both ends of trimethylsiloxy group of 0 mPa · s. An emulsion having crosslinked silicone particles in the silicone oil droplets was prepared. Water was removed from this emulsion in the same manner as in Example 1 to prepare a silicone oil composition having crosslinked silicone particles. This silicone oil composition was creamy. Observation of the silicone oil composition with an optical microscope showed that the crosslinked silicone particles were uniformly dispersed in the silicone oil, and that the shape of the crosslinked silicone particles was spherical.

Example 3 In Example 1, the amount of the dimethylsiloxane / methylvinylsiloxane copolymer added was 18.0 parts by weight, and the amount of the dimethylsiloxane / methylhydrogensiloxane copolymer was 2 .
An emulsion having crosslinked silicone particles in silicone oil droplets dispersed in water was prepared in the same manner as in Example 1 except that the amount was 0 part by weight. Water was removed from this emulsion in the same manner as in Example 1 to prepare a silicone oil composition having crosslinked silicone particles. This silicone oil composition was creamy. Observation of the silicone oil composition with an optical microscope showed that the crosslinked silicone particles were uniformly dispersed in the silicone oil, and that the shape of the crosslinked silicone particles was spherical.

Example 4 In Example 3, the viscosity was 10
Dispersed in water in the same manner as in Example 3 except that a dimethylpolysiloxane having a viscosity of 10 mPa · s and having both terminal trimethylsiloxy groups was used instead of the dimethylpolysiloxane having a molecular chain having both ends of trimethylsiloxy group and 0 mPa · s. An emulsion having crosslinked silicone particles in the silicone oil droplets was prepared. Water was removed from this emulsion in the same manner as in Example 3 to prepare a silicone oil composition having crosslinked silicone particles. This silicone oil composition was creamy. Observation of the silicone oil composition with an optical microscope showed that the crosslinked silicone particles were uniformly dispersed in the silicone oil, and that the shape of the crosslinked silicone particles was spherical.

Comparative Example 1 18.8 parts by weight of a dimethylsiloxane-methylvinylsiloxane copolymer having an average of 4.2 vinyl groups in one molecule and having a dimethylvinylsiloxy group at both ends of a molecular chain and having a viscosity of 350 mPa · s and having a viscosity of 350 mPa · s Having a content of silicon-bonded hydrogen atoms of about 0.5% by weight and a viscosity of 45 m
Equivalent to 1.2 parts by weight of a dimethylsiloxane / methylhydrogensiloxane copolymer having both ends of a trimethylsiloxy group having a Pa · s molecular chain and 80 parts by weight of a dimethylpolysiloxane having a trimethylsiloxy group having both ends of a molecular chain having a viscosity of 100 mPa · s. And then mixed with a colloid mill to prepare polyoxyethylene nonylphenyl ether (HLB = 13).
The emulsion was emulsified in an aqueous solution comprising 0.4 parts by weight and 49.8 parts by weight of pure water to prepare an emulsion of the silicone composition.

Next, a platinum-based catalyst containing a 1,3-divinyltetramethoxydisiloxane complex of platinum as a main component was emulsified in the emulsion of the silicone composition with the above aqueous solution of polyoxyethylene nonylphenyl ether. Emulsion (average particle size of platinum-based catalyst =
0.3 μm, platinum metal concentration = 0.05% by weight) was added to the silicone composition in an amount such that platinum metal was 20 ppm by weight, and the mixture was uniformly mixed. The composition was crosslinked by a hydrosilylation reaction to prepare an emulsion having crosslinked silicone particles in silicone oil droplets dispersed in water.

Further, the emulsion was transferred to an aluminum dish having a diameter of 5 cm and air-dried in a fume hood for one week to remove water, thereby preparing a silicone oil composition having crosslinked silicone particles. This silicone oil composition was creamy. Observation of the silicone oil composition with an optical microscope showed that the crosslinked silicone particles were uniformly dispersed in the silicone oil, and that the shape of the crosslinked silicone particles was spherical.

Comparative Example 2 44.5 parts by weight of a dimethylpolysiloxane having a vinylmethylsiloxy group at both ends of a molecular chain having a viscosity of 5 mPa · s and a content of silicon-bonded hydrogen atoms of 1.5% by weight were added to a planetary mixer. With a viscosity of 20 mPa
100 parts by weight of methyl hydrogen polysiloxane capped with trimethylsiloxy groups at both ends of the molecular chain of s, viscosity 6 mPa · s
Was mixed with 758 parts by weight of dimethylpolysiloxane endblocked by trimethylsiloxy groups at both ends of the molecular chain, and 0.5 parts by weight of a 2% by weight solution of chloroplatinic acid in isopropyl alcohol was added to prepare a crosslinkable silicone composition. . The crosslinkable silicone composition was stirred for 2 hours while being heated to 70 to 80 ° C. to perform a hydrosilylation reaction of the crosslinkable silicone composition, and the resulting silicone composition was kneaded with 3 rolls under shearing force. Thus, a paste-like silicone oil composition was prepared. Observation of this silicone oil composition with an optical microscope revealed that the crosslinked silicone particles of irregular shape were dispersed in the silicone oil, but the dispersion was uneven, and the particle size of the crosslinked silicone particles was as large as about 200 μm. I understand.

[0046]

[Table 1]

Comparative Example 3 94 parts by weight of a dimethylpolysiloxane endblocked with dimethylvinylsiloxy groups at both molecular chains having a viscosity of 400 mPa · s, the content of silicon-bonded hydrogen atoms was 0.5% by weight, and the viscosity was 30 mPa · s. After mixing 6 parts by weight of a dimethylsiloxane-methylhydrogensiloxane copolymer having a trimethylsiloxy group-blocked molecular chain at both ends,
A 3% by weight aqueous solution of polyoxyethylene nonylphenyl ether (HLB = 13.1) 53 was prepared by a colloid mill.
The emulsion was emulsified in parts by weight, and further diluted with 50 parts by weight of pure water to prepare an emulsion of the silicone composition.

Next, a platinum-based catalyst containing a 1,3-divinyltetramethoxydisiloxane complex of platinum as a main component and emulsified with the above-mentioned aqueous solution of polyoxyethylene nonylphenyl ether was added to the emulsion of the silicone composition. Emulsion (average particle size of platinum-based catalyst =
0.3 μm, platinum metal concentration = 0.05% by weight) was added to the silicone composition in an amount such that platinum metal was 20 ppm by weight, and the mixture was uniformly mixed. The composition was crosslinked by a hydrosilylation reaction to prepare an aqueous dispersion of crosslinked silicone particles.

In the aqueous dispersion of the crosslinked silicone particles,
Viscosity 100mP, 4 times the amount of crosslinked silicone particles
An emulsion of dimethylpolysiloxane (concentration: 50% by weight) having capped trimethylsiloxy groups at both ends of the molecular chain of a · s was blended and uniformly mixed. This mixture has a diameter of 5
The silicone oil composition consisting of silicone oil and crosslinked silicone particles was prepared by removing the water by transferring to an aluminum dish of cm and air-drying in a fume hood for 3 days. Although this silicone oil composition was creamy, the silicone oil was floating on the liquid surface, and observation with an optical microscope showed that the crosslinked silicone particles were unevenly dispersed in the silicone oil. Was.

[Example 5] In Example 1, the viscosity was 10
Isoparaffin having a viscosity of 2.4 mPa · s (ISOSOL 40 manufactured by Nippon Petrochemical Co., Ltd.) is used in place of dimethylpolysiloxane having a trimethylsiloxy group at both ends of the molecular chain of 0 mPa · s.
An emulsion having crosslinked silicone particles in isoparaffin droplets dispersed in water was prepared in the same manner as in Example 1 except that 0) was used. When this emulsion was evaluated in the same manner as in Example 1, it was found that the average particle size of the emulsion was 5 μm, and the thickness of the aqueous layer separated from the emulsion was 2 mm.

Water was removed from this emulsion in the same manner as in Example 1 to prepare an isoparaffin composition having crosslinked silicone particles. This isoparaffin composition was creamy. Observation of the isoparaffin composition with an optical microscope revealed that the crosslinked silicone particles were uniformly dispersed in the isoparaffin, the shape of the crosslinked silicone particles was spherical, and the average particle size was 3.0 μm. .

[Application Examples 1 and 2, Comparative Application Example 1] To evaluate the compoundability of the emulsion of the present invention in cosmetics and the dispersibility of oil and crosslinked silicone particles in the obtained cosmetics, Shampoo composition (Rinse-free <vegetable oil> soap shampoo manufactured by Oshima Tsubaki Honpo Co., Ltd.) 10
A shampoo composition was prepared by mixing 4 parts by weight of each of the emulsions prepared in Example 3, Example 4, and Comparative Example 1 with 0 parts by weight and shaking and stirring 50 times. These shampoo compositions were evaluated for lathering properties, hair feel, coating weight, and stability as follows, and the results are shown in Table 3. [Adhesion amount] In a beaker with two flat blades, 5 g of the hair bundle was put into an aqueous solution consisting of 100 g of the shampoo composition and 400 g of water, stirred at 100 rpm for 5 minutes, and then the shampoo solution was removed. At 100 rpm
The hair was washed three times with stirring at rpm for 3 minutes, water was removed from the hair, the hair was dried with hot air using a dryer, and the weight was measured. The value obtained by subtracting the weight before the test from the dry weight was defined as the adhesion amount. [Feel of Hair] The appearance and feel of the hair after the adhesion amount measurement were evaluated. [Bubbling property] 500 ml of a 1% aqueous solution of the prepared shampoo composition was placed in a 1 liter beaker, and 2.5 g of lanolin as an artificial soil was added thereto.
Invert stirring at 1000 rpm for 10 seconds with a flat stirring blade for 5 seconds.
After stirring, the mixture was transferred to a 1-liter measuring cylinder, and the foam volume after standing for 30 seconds was measured. [Stability] 100 g of the shampoo composition was collected in a glass bottle, and allowed to stand in a 45 ° C constant temperature bath for 10 days. Observing the appearance of the shampoo composition, when there is no separation, `` ○ '',
The case where there was separation was evaluated as "x".

[0053]

[Table 2]

[0054]

The emulsion of the present invention is an emulsion containing crosslinked silicone particles in oil droplets emulsified in an aqueous solution of a surfactant, and has good mixability with cosmetics and the like. It is characterized in that the oil and the crosslinked silicone particles have good dispersibility in a composition such as a cosmetic, and the effect of the combination of the oil and the crosslinked silicone particles can be sufficiently exhibited. Further, the method for producing an emulsion of the present invention is characterized in that such an emulsion can be produced efficiently.

Claims (10)

[Claims] 1. An oil droplet having an average particle size of 0.5 to 500 μm emulsified in an aqueous surfactant solution and having an average particle size of 0.5 to 500 μm.
An emulsion containing 1 to 100 μm crosslinked silicone particles (where the particle size of the crosslinked silicone particles is smaller than the particle size of the oil droplets), wherein the surfactant is zwitterionic; An emulsion comprising: 2. The oil has a viscosity of 1 to 10 at 25 ° C.
2. The emulsion according to claim 1, wherein the emulsion has a concentration of 0,000,000 mPa · s. 3. The emulsion according to claim 1, wherein the crosslinked silicone particles are obtained by crosslinking a crosslinkable silicone composition by a hydrosilylation reaction or a condensation reaction. 4. The amphoteric surfactant has 11 to 1 carbon atoms.
The emulsion according to claim 1, which contains 7 alkyl groups. 5. The emulsion according to claim 1, wherein the zwitterionic surfactant is of the betaine type. 6. A cross-linkable silicone composition containing a non-cross-linkable oil (however, the content of the non-cross-linkable oil is more than an amount that a cross-linked product of the cross-linkable silicone composition can hold the oil). Is cross-linked in an aqueous surfactant solution in an emulsified state to obtain an average particle size of 0.5 to 50.
A method for producing an emulsion in which 0 μm oil droplets contain crosslinked silicone particles having an average particle size of 0.1 to 100 μm (where the particle size of the crosslinked silicone particles is smaller than the particle size of the oil droplets). Wherein said surfactant is a zwitterionic one. 7. The method according to claim 6, wherein the viscosity of the non-crosslinkable oil at 25 ° C. is 1 to 100,000,000 mPa · s. 8. The method according to claim 6, wherein the crosslinkable silicone composition is crosslinked by a hydrosilylation reaction or a condensation reaction. 9. The amphoteric surfactant has 11 to 1 carbon atoms.
7. The method for producing an emulsion according to claim 6, comprising an alkyl group of (7). 10. The method for producing an emulsion according to claim 6, wherein the zwitterionic surfactant is a betaine type.