WO2022138480A1

WO2022138480A1 - O/w type emulsion composition containing polymer

Info

Publication number: WO2022138480A1
Application number: PCT/JP2021/046704
Authority: WO
Inventors: 真喜子宮本; 博史山口
Original assignee: 住友精化株式会社
Priority date: 2020-12-25
Filing date: 2021-12-17
Publication date: 2022-06-30

Abstract

Provided is an O/W type emulsion composition having improved emulsification stability.　More particularly, provided is an O/W type emulsion composition containing a water absorbent polymer, wherein the water absorbent polymer satisfies the following conditions (A), (B) and (C): (A) after swelling with water, having a particle size of 100 to 600 μm; (B) satisfying the following conditions (B-1) and/or (B-2): (B-1) in a double logarithmic graph of the steady-state flow viscosity of a 1 mass% aqueous solution of the polymer, the inclination being -1 or more and less than 0 (in the shear rate range of 0.1 to 1,000 s^-1); and (B-2) the yield stress/yield strain balance of the 1 mass% aqueous solution of the polymer being 10 or more; and (C) when an aqueous solution of 1 mass% of the polymer and 0.5 mass% of sodium chloride is sieved through a sieve with a 75 µm aperture, the amount of the polymer remaining on the sieve being 50 mass% or less of the amount of the polymer contained in the aqueous solution.

Description

Polymer-containing O / W emulsion composition

The present disclosure relates to an O / W type emulsion composition containing a polymer and the like. The contents of all documents described in this specification are incorporated herein by reference.

The O / W type emulsion composition is applied to various fields. For example, it is applied to the fields of adhesives and cosmetics.

For example, in the field of cosmetics, it has been attempted to add an active ingredient to an O / W type emulsion and, for example, to add a polymer (particularly a water-absorbent polymer) to impart a good affinity to the skin. There is.

Japanese Unexamined Patent Publication No. 2011-6413

When using an O / W type emulsion composition as, for example, a cosmetic composition, its stability is important. If the stability is poor, the active ingredient contained in the oil phase may be separated, and the effect may not be exhibited efficiently. In addition, the separation also deteriorates the appearance.

In particular, many sunscreen (sunscreen) compositions are O / W emulsion compositions that contain various active ingredients (eg, moisturizers and UV absorbers) and are less stable. The active ingredient separates.

Therefore, the present inventors have proceeded with studies to develop a technique for further enhancing the emulsion stability of the O / W type emulsion composition.

The present inventors have found that the O / W type emulsion composition containing a specific water-absorbent polymer has extremely high stability and component separation is unlikely to occur, and further improvements have been made.

The present disclosure includes, for example, the subjects described in the following sections.
Item 1.
An O / W type emulsion composition containing a water-absorbent polymer.
The water-absorbent polymer has the following conditions (A), (B), and (C):
(A): The particle size after water swelling is 100 to 600 μm (B): At least one of the following (B-1) and (B-2) is satisfied (B-1): 1% by mass aqueous solution of polymer. The slope in the log-log graph of the steady flow viscosity of -1 or more and less than 0 (in the range of shear velocity 0.1 to 1,000 s ^-1 )
(B-2): Balance of yield stress / yield strain of 1% by mass aqueous solution of polymer is 10 or more (C): When an aqueous solution of 1% by mass of polymer and 0.5% by mass of sodium chloride is sieved with an opening of 75 μm. A polymer satisfying that the amount of polymer remaining on the sieve is 50% by mass or less of the amount of the aqueous solution-containing polymer.
Composition.
Item 2.
The composition according to claim 1, further comprising an organic UV protection agent.
Item 3.
The composition according to claim 2, wherein the organic UV protection agent is a lipophilic organic UV protection agent.
Item 4.
The invention according to any one of claims 1 to 3, wherein the water-absorbent polymer is a polymer obtained by polymerizing a water-soluble unsaturated carboxylic acid monomer (preferably (meth) acrylic acid) in the presence of a cross-linking agent. Composition.
Item 5.
The composition according to claim 4, wherein the cross-linking agent is at least one selected from the group consisting of water-soluble sucrose allyl ether, ethylene glycol diglycidyl ether, and pentaerythritol allyl ether.
Item 6.
The composition according to any one of claims 1 to 5, further containing silica.

Provided is an O / W type emulsion composition having high stability and suppressed component separation.

In addition, when an O / W type emulsion composition is used as a cosmetic composition, generally, oil components such as moisturizing components and ultraviolet absorbers contained in the composition can cause sliminess at the time of application, whereas those with poor emulsification are used. It is easier to get slimy than a stable one. However, it can also be said that the O / W type emulsion composition provided by the present disclosure has high stability and suppresses component separation, so that the sliminess is reduced and therefore the tactile sensation is improved. Therefore, it is particularly suitable for use as an external composition such as a cosmetic composition.

The steady flow viscosity was measured in the range of shear rate 0.000001 to 1,000 s ^-1 using a rheometer, and the graph of the shear rate in the range of 0.1 to 1,000 s-1 is shown. Polymer A: y = 126.01x ^-0.736 , Polymer B: y = 110.39x ^-0.697 , Polymer C: y = 50.755x ^-0.66 The relationship between stress (Pa) and strain (%) when the steady flow viscosity is measured in the range of shear rate 0.000001 to 1,000s ^-1 using a rheometer is shown. Polymer A: 45.8Pa, 4.3%, Polymer B: 21.3Pa, 1.5%, Polymer C: 15.7Pa, 2.8%

Hereinafter, each embodiment included in the present disclosure will be described in more detail. The present disclosure preferably includes, but is not limited to, O / W type emulsion compositions and their uses, methods for producing them, and the like, and the present disclosure is all disclosed herein and recognized by those skilled in the art. Including.

The O / W type emulsion composition included in the present disclosure contains a specific water-absorbing polymer. Hereinafter, the O / W type emulsion composition included in the present disclosure may be referred to as "the composition of the present disclosure".

The specific water-absorbent polymer contained in the composition of the present disclosure is a polymer satisfying the following conditions (A), (B), and (C). The specific water-absorbent polymer may be referred to as "the polymer of the present disclosure".
(A): The particle size after water swelling is 100 to 600 μm (B): At least one of the following (B-1) and (B-2) is satisfied (B-1): 1% by mass aqueous solution of polymer. The slope in the log-log graph of the steady flow viscosity of -1 or more and less than 0 (in the range of shear velocity 0.1 to 1000s ^-1 )
(B-2): Balance of yield stress / yield strain of 1% by mass aqueous solution of polymer is 10 or more (C): When an aqueous solution of 1% by mass of polymer and 0.5% by mass of sodium chloride is sieved with an opening of 75 μm. The amount of polymer remaining on the sieve is 50% by mass or less of the amount of the aqueous solution-containing polymer.

As described in (A) above, the polymer of the present disclosure is a polymer having a particle size of 100 to 600 μm when it absorbs water and swells. In the composition of the present disclosure, since the polymer of the present disclosure is present in the aqueous phase and absorbs water and swells, (A) defines the particle size of the swollen water-absorbent polymer in the composition of the present disclosure. It can be said that it is doing.

The upper or lower limit of the particle size range (100 to 600 μm) when water is absorbed and swollen is, for example, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200, 210, 220. , 230, 240, 250, 260, 270, 280, 290, 300, 310, 320, 330, 340, 350, 360, 370, 380, 390, 400, 410, 420, 430, 440, 450, 460, 470. It may be 480, 490, 500, 510, 520, 530, 540, 550, 560, 570, 580, or 590 μm. For example, the range may be 110 to 590 μm.

The particle size is a medium particle size having a volume average particle size measured by a laser diffraction method. As a measuring device (laser diffraction type particle size distribution measuring device) by this method, for example, SALD-2300 (manufactured by Shimadzu Corporation) can be used.

Further, as described in (B) above, the polymer of the present disclosure satisfies at least one of (B-1) and (B-2). That is, the polymer of the present disclosure satisfies at least one of the conditions (B-1) or (B-2), and preferably both of these conditions. These conditions can be measured (and calculated) by measuring the steady flow viscosity of the 1% by mass aqueous solution of the polymer of the present disclosure with a rheometer. More specifically, it can be measured and calculated by measuring the steady flow viscosity using an aluminum parallel plate (diameter: 60 mm, Gap: 1000 μm). Examples of the rheometer include those manufactured by TA Instruments.

For the slope of the steady flow viscosity of (B-1), create a log-log graph of x-axis: shear rate (s ^-1 ) and y-axis: viscosity (Pa · s), and slope from the approximate straight line of the plot. It can be measured by reading (y = value of a of Cx ^a ). The slope of the steady flow viscosity is a slope in the range of shear rate (that is, x =) 0.1 to 1,000 s ^-1 . The slope of the steady flow viscosity is -1 or more and less than 0, preferably -1 to −0.05 as described above. The upper or lower limit of the range is, for example, -0.95, -0.9, -0.85, -0.8, -0.75, -0.7, -0.65, -0.6,- At 0.55, -0.5, -0.45, -0.4, -0.35, -0.3, -0.25, -0.2, -0.15, or -0.1 There may be. For example, the range may be −0.9 to −0.1.

The balance of yield stress / yield strain in (B-2) is as follows. Create a logarithmic graph of x-axis: stress (Pa) and y-axis: strain (%), read the stress (Pa) and strain (%) at the point where the slope of the plot changes abruptly, and calculate the stress. The yield stress was defined as the yield stress, the yield stress (Pa) value was divided by the yield strain (%) value, and the value was defined as the “yield stress / yield strain balance”. The yield stress / yield strain balance is 10 or more, preferably 10 to 40, as described above. The upper or lower limit of the range is, for example, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31. , 32, 33, 34, 35, 36, 37, 38, or 39. For example, the range may be about 11 to 30.

In the log-log graph, a polymer having a value of 100 Pa · s or more when x = 1 (that is, a shear rate of 1 s ^-1 ) is particularly preferable, and a polymer having a value of 100 to 500 Pa · s is more preferable. The upper limit or the lower limit of the range is not particularly limited, and for example, 105, 110, 115, 120, 125, 130, 135, 140, 145, 150, 160, 170, 180, 190, 200, 250, 300, 350, 400. , Or 450. For example, the range may be 105 to 200 Pa · s.

Further, as described in (C) above, in the polymer of the present disclosure, when an aqueous solution of 1% by mass of polymer and 0.5% by mass of sodium chloride is sieved with an opening of 75 μm, the amount of polymer remaining on the sieve is the amount of the aqueous solution-containing polymer. It is a polymer having an amount of 50% by mass or less. Further, the lower limit of the amount of polymer remaining on the sieve is not particularly limited, but for example, 1% by mass or more of the amount of polymer contained in the aqueous solution is exemplified. The upper or lower limit of the range (1 to 50% by mass) is, for example, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, It may be 44, 45, 46, 47, 48, or 49% by mass. For example, the range may be 10 to 45% by mass. An aqueous solution containing 1% by mass of the polymer of the present disclosure and 0.5% by mass of sodium chloride is prepared, stirred well, and then the aqueous solution is poured onto a sieve having an opening of 75 μm, and the mass of the polymer remaining on the sieve is measured. By doing so, it is possible to examine whether or not the condition (C) is satisfied.

The viscosity of the 1% by mass polymer and 0.5% by mass aqueous solution of sodium chloride is lower than that of the 1% by mass aqueous solution of the polymer, but the viscosity is still high. Therefore, simply pouring an aqueous solution of 1% by mass of polymer and 0.5% by mass of sodium chloride onto a sieve may require a very long time for filtration. Therefore, in such a case, filtration may be promoted by lightly tracing a 1% by mass polymer and a 0.5% by mass aqueous solution of sodium chloride on the sieve with a spatula.

Further, the post-swelling polymer contained in the 1% by mass polymer and the 0.5% by mass aqueous solution of sodium chloride is partially shrunk as compared with the post-swelling polymer contained in the 1% by mass aqueous solution of the polymer (thus, the viscosity is lowered). ), A 75 μm sieve will be sieved. Therefore, both the above conditions (A) and (C) can be satisfied. From this, the condition of (C) is that when sodium chloride is added to a 1% by mass aqueous solution of the polymer so as to have 0.5% by mass of sodium chloride, it shrinks and sifts a 75 μm sieve. In other words, the proportion of the polymer is 50% by mass or more of the amount of the aqueous solution-containing polymer. In this paraphrase, the upper limit of the proportion of the polymer is not particularly limited, but 99% is exemplified. The upper or lower limit of the range (50 to 99% by mass) is, for example, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, It may be 93, 94, 95, 96, 97, or 98% by mass. For example, the range may be 55 to 90% by mass.

The polymer of the present disclosure is not particularly limited as long as it satisfies the above (A), (B) and (C), but above all, a water-soluble unsaturated carboxylic acid monomer is polymerized in the presence of a cross-linking agent. The polymer thus obtained is preferred.

The polymer can be obtained, for example, by a method including a step of polymerizing a water-soluble unsaturated carboxylic acid monomer by a suspension polymerization method in the presence of a cross-linking agent. Among the suspension polymerization methods, a reverse phase suspension polymerization method in which a polymerization reaction is carried out while dispersing droplets of an aqueous phase containing a water-soluble unsaturated carboxylic acid monomer, a cross-linking agent and water in a hydrophobic solvent is preferable. ..

The water-soluble unsaturated carboxylic acid monomer is not particularly limited, and examples thereof include acrylic acid, methacrylic acid, maleic acid, maleic anhydride, fumaric acid, crotonic acid, and itaconic acid. Of these, acrylic acid and methacrylic acid are preferable. The water-soluble unsaturated carboxylic acid monomer can be used alone or in combination of two or more. Of these, (meth) acrylic acid (acrylic acid and / or methacrylic acid) is preferable.

As the cross-linking agent, for example, a known cross-linking agent used in the technical field (particularly, the water-absorbent resin field) can be used. More specifically, for example, water-soluble sucrose allyl ether, ethylene glycol diglycidyl ether, pentaerythritol allyl ether and the like can be preferably used. The cross-linking agent may be used alone or in combination of two or more. Specific examples of the pentaerythritol allyl ether include pentaerythritol triallyl ether and pentaerythritol tetraallyl ether.

When water-soluble sucrose allyl ether is used as the cross-linking agent, the degree of etherification of the water-soluble sucrose allyl ether is preferably 1.8 to 3.5, more preferably 2.0 to 3.2. This degree of etherification is the average value of the molar ratio of allyl ether groups to sucrose. The degree of etherification can be calculated from the amount of acetic anhydride consumed by reacting the hydroxyl groups remaining in the sucrose allyl ether with acetic anhydride in pyridine. Further, the water-soluble sucrose allyl ether can be obtained, for example, by adding sodium hydroxide as a catalyst to an aqueous sucrose solution, converting sucrose into alkaline sucrose, and then dropping allyl bromide to carry out etherification. be able to. At this time, by adjusting the amount of allyl bromide in the range of 2 to 6 times mol, preferably 2 to 5 times mol, of sucrose, water-soluble sucrose allyl ether can be efficiently obtained. .. The reaction temperature for etherification is, for example, about 80 ° C. Usually, the reaction is completed about 3 hours after the dropping of allyl bromide. The water-soluble sucrose allyl ether can be recovered by adding alcohol to the aqueous phase separated from the reaction solution, filtering out the precipitated salts, and then distilling off excess alcohol and water.

As the hydrophobic solvent used for the reverse phase suspension polymerization, for example, a petroleum-based hydrocarbon solvent selected from an aliphatic hydrocarbon, an alicyclic hydrocarbon and an aromatic hydrocarbon is used. Examples of the aliphatic hydrocarbon include n-pentane, n-hexane and n-heptane. Examples of the alicyclic hydrocarbon include cyclopentane, methylcyclopentane, cyclohexane and methylcyclohexane. Examples of aromatic hydrocarbons include benzene, toluene and xylene. In particular, at least one hydrophobic solvent selected from n-hexane, n-heptane, cyclohexane and toluene is preferably used as an industrial general purpose solvent. The ratio of the hydrophobic solvent is, for example, 100 to 200 parts by mass with respect to 100 parts by mass of the aqueous phase containing the water-soluble unsaturated carboxylic acid monomer and the like.

In the case of reverse phase suspension polymerization, the aqueous phase containing a water-soluble unsaturated carboxylic acid monomer or the like, or the hydrophobic solvent may contain other components such as a surfactant and a radical initiator.

Surfactants are mainly used to stabilize the suspension during polymerization. The surfactant is not particularly limited as long as it is usually used in reverse phase suspension polymerization. Preferably, sorbitan fatty acid ester, polyglycerin fatty acid ester, sucrose fatty acid ester, sorbitol fatty acid ester, modified polyethylene wax, modified polypropylene wax, polyvinyl alcohol, polyethylene oxide, cellulose ether (hydroxyethyl cellulose, ethyl cellulose, etc.), sodium alkylbenzene sulfonate, And one or more surfactants selected from polyoxyethylene alkyl phenyl ether sulfates are used.

The amount of the surfactant is preferably 0.1 to 10% by mass, more preferably 0.5 to 5% by mass with respect to the water-soluble unsaturated carboxylic acid monomer.

The radical initiator is not particularly limited as long as it is used for ordinary radical polymerization, but potassium persulfate, ammonium persulfate, sodium persulfate, an azo-based initiator and the like are preferably used. For example, 2,2'-azobis (2-methylpropionamidine) dihydrochloride can be used as a radical initiator.

The amount of the radical initiator is preferably 0.01 to 0.5% by mass, more preferably 0.02 to 0.2% by mass, based on the water-soluble unsaturated carboxylic acid monomer. When the amount of the radical initiator is within this range, the polymerization reaction can proceed more efficiently, and the obtained polymer is more excellent in thickening when used as a hydrophilic thickener.

During reverse phase suspension polymerization, the size of the droplets containing the water-soluble unsaturated carboxylic acid monomer and the like is closely related to the size of the obtained polymer particles. Although it depends on the conditions such as the reaction vessel and the production scale, for example, when a 2 L flask is used as the reaction vessel, a polymer of an appropriate size can be polymerized by performing reverse phase suspension polymerization at a stirring speed of 800 to 1000 rpm. It is likely that particles can be obtained. In this way, by adjusting the stirring speed during the polymerization reaction and controlling the size of the polymer particles (resin particles), the medium particle size of the obtained resin particles can be adjusted. For example, resin particles having a size of 5 to 30 μm can be obtained. Since the shape of the polymer particles thus obtained is spherical and is retained even in an aqueous liquid or a viscous substance such as cosmetics, for example, in cosmetics using the same, various properties, touch and usability can be obtained. It is considered to have a positive effect.

The medium particle size of the particles is the medium particle size of the volume average particle size measured by the laser diffraction method in which the particles are dispersed in n-hexane. As a measuring device (laser diffraction type particle size distribution measuring device) by this method, for example, SALD-2300 (manufactured by Shimadzu Corporation) can be used.

The medium particle size of the particles is preferably 5 to 30 μm, more preferably 5 to 25 μm, and even more preferably 6 to 20 μm. By adjusting the medium particle size of the particles, the particle size when water is absorbed and swollen can also be adjusted. That is, by increasing the medium particle size of the particles, the particle size when water is absorbed and swollen can be increased, and by reducing the medium particle size of the particles, water is absorbed and swollen. The particle size can also be reduced.

Other conditions of the polymerization reaction, such as the amount of radical initiator, the polymerization reaction temperature, the reaction time, etc. are also adjusted as appropriate. The polymerization reaction temperature is, for example, 50 to 80 ° C., and the reaction time is, for example, 30 minutes to 3 hours. For example, when a 2 L flask is used as a reaction vessel, the bath temperature can be adjusted to 60 ° C. to start the polymerization reaction. In this case, the start of the polymerization reaction can be confirmed from the fact that the temperature inside the reaction vessel rises to about 70 ° C. due to the heat of polymerization. After that, the polymerization reaction is usually completed by carrying out the aging reaction for about 30 minutes to 3 hours. If the aging time is shorter than that, the reaction may not be completed sufficiently and the amount of remaining water-soluble unsaturated carboxylic acid monomer may increase. After the aging reaction, the product can be obtained by raising the bath temperature and distilling off the water and the petroleum-based hydrocarbon solvent in the reaction vessel.

The degree of neutralization of the polymer can be easily adjusted by neutralizing the carboxyl group of the water-soluble unsaturated carboxylic acid with an alkali. The degree of neutralization here refers to the ratio of the number of moles of neutralized groups to the total number of moles of carboxyl groups of the water-soluble unsaturated carboxylic acid. Examples of the alkali used for neutralization include sodium hydroxide, potassium hydroxide, triethanolamine, diisopropylamine and the like. The neutralization method is not particularly limited, and examples thereof include a method of neutralizing a water-soluble unsaturated carboxylic acid monomer in advance, a method of neutralizing a polymer obtained by polymerization, and the like.

The degree of neutralization of the polymer of the present disclosure is not particularly limited, but may be, for example, 95% or less. For example, 90% or less is preferable, 85% or less or 80% or less is more preferable, and 75% or less is further preferable. The lower limit of the degree of neutralization is not particularly limited, and examples thereof include 0% or more or 5% or more. The upper or lower limit of the neutralization degree range (0% to 95%) is, for example, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, It may be 91, 92, 93, or 94%. For example, the range may be 20 to 80%, and more preferably about 40 to 75%.

The amount of the cross-linking agent used is not particularly limited, but is preferably 0.01 to 1 part by mass, more preferably 0.05 to 0.8 parts by mass with respect to 100 parts by mass of the water-soluble unsaturated carboxylic acid monomer. , 0.1-0.6 parts by mass is more preferable.

Although not particularly limited, the polymer particles of the present disclosure absorb water and swell in the composition of the present disclosure, so that the medium particle size thereof is preferably about 8 to 10 times larger than that before compounding. .. As described above, the medium particle size of the absorbed particles is 100 to 600 μm. The medium particle size is the medium particle size of the volume average particle size measured by the laser diffraction method. As a measuring device (laser diffraction type particle size distribution measuring device) by this method, for example, SALD-2300 (manufactured by Shimadzu Corporation) can be used.

The composition of the present disclosure may contain various components other than the polymer of the present disclosure. For example, when the composition of the present disclosure is used as an external composition (particularly a pharmaceutical composition or a cosmetic composition), it may contain a known ingredient used in the art.

For example, when the composition of the present disclosure is used as a cosmetic composition (particularly a sunscreen composition), an ultraviolet protective agent can be preferably used.

The UV protection agent is not particularly limited, but is preferably an organic compound (that is, an organic UV protection agent).

Further, the ultraviolet protective agent means an agent capable of protecting the influence of ultraviolet rays on the skin, and includes, for example, an ultraviolet absorber and an ultraviolet scattering agent.

Further, as the UV protection agent, there are a lipophilic UV protection agent and a hydrophilic UV protection agent, but since the composition of the present disclosure is an O / W type emulsion composition, any UV protection agent can be used. , Either one or both can be used. In the compositions of the present disclosure, the lipophilic UV protection agent may be contained in the oil phase (O phase) and the hydrophilic UV protection agent may be contained in the aqueous phase (W phase).

As the UV protection agent, those known in the art can be used. The lipophilic organic UV protection agent and the hydrophilic organic UV protection agent are illustrated below.

Examples of the oil-based organic ultraviolet protective agent include paraaminobenzoic acid derivatives, salicylic acid derivatives, silicic acid derivatives, benzophenone or aminobenzophenone, anthranyl acid derivatives, dibenzoylmethane derivatives, β, β-diphenylacrylate derivatives, benzilidencanfer derivatives, and phenyl. Benzoimidazole derivative, benzotriazole derivative, triazine derivative, bisresorcinyl triazine, imidazoline derivative, benzalmaronate derivative, 4,4-diarylbutadiene derivative, benzoxazole derivative, merocyanine, diphenylbutadiene malonate or diphenylbutadiene malonitrile derivative , Calcon and the like are exemplified.

Examples of the lipophilic UV-A protective agent capable of absorbing UV rays of 320 to 400 nm include the following.

Examples of dibenzoylmethane derivatives include 4-isopropyldibenzoylmethane, 1- (4-methoxy-1-benzofuran-5-yl) -3-phenylpropane-l, 3-dione, 1- (4- (tert-butyl). ) Phenyl) -3- (2-Hydroxyphenyl) Propane-1,3-dione, butylmethoxydibenzoylmethane (t-butylmethoxydibenzoylmethane), aminobenzophenone, and 2- (4-diethylamino-2-hydroxybenzoyl) ) N-hexyl benzoate, etc. Examples of the anthranilic acid derivative include anthranilic acid menthyl and the like. Examples of the 4,4-diarylbutadiene derivative include 1,1-dicarboxy- (2,2'-dimethylpropyl) -4,4-diphenylbutadiene.

Examples of the lipophilic UV-B protective agent capable of absorbing UV rays of 280 to 320 nm include the following. In addition, "PABA" indicates "para-aminobenzoic acid".

Examples of para-aminobenzoate include ethyl PABA, ethyldihydroxypropyl PABA, and ethylhexyldimethyl PABA. Examples of the salicylic acid derivative include homosalate, ethylhexyl salicylate, dipropylene glycol salicylate, TEA salicylic acid and the like. Examples of the cinnamic acid derivative include ethylhexyl methoxycinnamate, isopropyl methoxycinnamate, isoamyl methoxycinnamate, diisopropyl methoxycinnamate, cinoxate, and glyceryl hexaneate ethyl methoxycinnamate. Examples of the β, β-diphenylacryllate derivative include octocrylene and ethocrylene. Examples of the benzylidene camphor derivative include 3-benzylidene camphor, methyl benzylidene camphor, polyacrylamide methyl benzylidene camphor and the like. As triazine derivatives, for example, ethylhexyltriazone, diethylhexylbutamidotriazone, 2,4,6-tris (4'-dineopentyl aminobenzalmaronate) -s-triazine, 2,4,6-tris (4' -Diisobutyl aminobenzoate)-s-triazine, 2,4-bis (4'-dineopentyl aminobenzoate) -6- (4'-n-butyl aminobenzoate)-s-triazine, 2, Examples thereof include 4-bis (4'-aminobenzoic acid n-butyl) -6- (aminopropyl-trisiloxane) -s-triazine. Examples of the imidazoline derivative include ethylhexyl dimethoxybenzylidendioxoimidazoline propionate. Examples of the benzalmalonate derivative include polyorganosiloxane containing a benzalmalonate functional group such as polysilicone-15, dineopentyl 4'-methoxybenzalmalonate and the like. Examples of the merocyanine derivative include octyl 5-N, N-diethylamino-2-phenylsulfonyl-2,4-pentadiene.

Examples of lipophilic wide-area UV protection agents capable of absorbing UV-A and UV-B rays include the following.

Examples of the benzophenone derivative include benzophenone-1 (oxybenzone-1), benzophenone-2 (oxybenzone-2), benzophenone-3 (oxybenzone-3), benzophenone-8 (oxybenzone-8), and benzophenone-10 (oxybenzone-10). , Benzophenone-11 (oxybenzone-11), benzophenone-12 (oxybenzone-12) and the like. Examples of the benzotriazole derivative include drometrizoletrisiloxane and bumetrizole. Examples of the bisresorcinyltriazine derivative include bisethylhexyloxyphenol methoxyphenyltriazine and the like. Examples of the benzoxazole derivative include 2,4-bis [5-1 (dimethylpropyl) benzoxazole-2-yl- (4-phenyl) imino] -6- (2-ethylhexyl) imino-1,3,5-triazine and the like. Can be mentioned.

Derivatives of the family of diphenylbutadiene malonate or diphenylbutadiene malonitrile are compounds represented by the following general formulas.

In the formula, R ³ represents a C1-C2 alkyl group or a C1-C2 alkoxy group, where n is equal to 0, 1 or 2;
R ⁴ and R ⁵ are the same or different and represent -COOR ⁶ ,-(C = O) NHR ⁶ ,-(C = O) R ⁶ or -CN (in the equation, R ⁶ is 1). Represents a linear or branched alkyl group containing up to 12 carbon atoms and capable of containing a silane, siloxane or polysiloxane group).

Specifically, among diphenylbutadiene malonate or diphenylbutadiene malonitrile derivative, for example,
2- (3,3-diphenylprop-2-enylidene) dimethyl malonate,
2- (3,3-diphenylprop-2-enylidene) diisobutyl malonic acid,
2- (3,3-diphenylprop-2-enylidene) bis-malonate (1,3-dimethylbutyl), 2- (3,3-diphenylprop-2-enylidene) dineopentyl malonic acid,
(2Z) -2-cyano-5,5-diphenylpenta-2,4-methyl dieneate,
(2Z) -2- (3,3-diphenylprop-2-enylidene) ethyl malonate (trimethylsilyl) methyl,
(2E) -2-cyano-5,5-diphenyl-N- (3- {1,3,3,3-tetramethyl-1-[(trimethylsilyl) oxy] disyloxanyl} propyl) penta-2,4-dienamide ,
2-Methyl-3- {1,3,3,3-tetramethyl-1-[(trimethylsilyl) oxy] disyloxanyl} propyl (2E) -2- (3,3-diphenylprop-2-enylidene) ethyl malonate , (2Z) -5,5-diphenyl-2-{[(3- {1,3,3,3-tetramethyl-1-[(trimethylsilyl) oxy] disiloxanyl} propyl) amino] carbonyl} penta-2, 4-Ethyl dienoate,
And so on.

Specifically, among the above diphenylbutadiene derivatives, for example, the following formula:

It is preferable to use dineopentyl 2- (3,3-diphenylprop-2-enylidene) malonic acid corresponding to.

It is known to use these diphenylbutadiene derivatives in sun protection compositions, European Patent No. 0 916 335 describes carbon derivatives and methods for their preparation, European Patent Nos. 1 535 947 and European Patents. No. 1 535 925 describes siloxane and silane derivatives, respectively.

Derivatives of the chalcone family are, for example, compounds represented by the following general formulas.

In the formula, the R ⁷ and R ⁸ groups are independent of each other, a hydrogen atom, a hydroxy group, a linear or branched C1-C12 alkyl or alkenyl group, and a linear or branched C1-C12 alkoxy group. Or means a linear or branched C2-C20 acyloxy group;
p and q mean the same or different 0, 1, 2, 3, 4, or 5

Specifically, among the chalcone derivatives, for example
2'-Hydroxy chalcone,
4'-Hydroxy chalcone,
4'-Methoxychalcone,
2'-Hydroxy-4-methoxychalcone,
2'-Hydroxy-4-hexyloxychalcone,
2'-Hydroxy-4-methyl chalcone,
2'-Hydroxy-3-hexyloxychalcone,
2'-Hydroxy-4'-Hexyloxy-4-methylchalcone,
2'-Hydroxy-4'-hexanoyloxy-4-methoxychalcone,
2', 4', 4-trihydroxy-3,3'-diallyl chalcone (known as Kazonol), 2', 4', 4-trihydroxy-5'-(3-methylbut-2-) Enil) Chalcone (known as Broussochalcone B),
2', 3', 4', 6', 4-pentahydroxychalcone (known as Carthamin) and the like can be mentioned.

Among the above chalcone derivatives, the following formula:

Corresponding to 4'-hydroxychalcone,
Or the following formula:

The corresponding 2', 3', 4', 6', 4-pentahydroxychalcones (known as Carthamin) can be preferably used.

Lipophilic organic UV protection agents are particularly preferred.
Salicylic acid derivatives, specifically homosalate or ethylhexyl salicylate,
Cinnamic acid derivatives such as ethylhexyl methoxycinnamate,
Β, β-diphenylacryllate derivatives such as octocrylene,
Dibenzoylmethane derivatives such as butylmethoxydibenzoylmethane,
Triazine derivatives such as ethylhexyltriazone or diethylhexylbutamidotriazone,
Benzotriazole derivatives such as drometrizoletrisiloxane,
And their mixtures can be selected.

Among the hydrophilic UV protection agents that can be used according to the present invention
Telephthalylidenedic camphor sulfonic acid,
Bisbenzoxazolyl derivatives, more specifically phenyldivene imidazole tetrasulfonate disodium, etc.
P-aminobenzoic acid (PABA) derivatives such as PABA, glyceryl PABA, PEG-25 PABA, phenylbenzimidazole sulfonic acid,
Ferulic acid,
Salicylic acid,
Ocyl methoxycinnamate DEA,
Benzylidene camphorsulfonic acid,
Camphor Benzalkonium Methosulfate Benzophenone-4,
Benzophenone-5, benzophenone-9 and the like can be particularly preferred.

Further, as an ingredient capable of forming an aqueous phase, for example, an ingredient known in the cosmetics field can be used. For example, water and a hydrophilic organic solvent can be mentioned. More specifically, such an organic solvent includes linear or branched lower monoalcohols having 1 to 8 carbon atoms such as ethanol, propanol, butanol, isopropanol or isobutanol, as well as propylene. Examples thereof include polyols such as glycol, isoprene glycol, butylene glycol, propylene glycol, glycerol (glycerin), sorbitol, polyethylene glycol, and derivatives thereof. Alternatively, hydrophilic ultraviolet light is also a component that can form an aqueous phase. These components can be used alone or in combination of two or more.

Further, as the component capable of forming the oil phase, for example, a component known in the field of cosmetics can be used. For example, hydrocarbon oils, vegetable oils and fats, fatty acids, fatty acid esters and the like can be mentioned. Although not particularly limited, more specifically, for example, the following components are exemplified.
Hydrocarbon oils of animal or plant origin, such as squalane, perhydrosqualene;
Triglyceride of heptanic acid or octanoic acid, or, for example, sunflower oil, corn oil, soybean oil, cucumber oil, grapeseed oil, sesame oil, hazelnut oil, apricot oil, macadamia oil, arara oil, sunflower oil or avocado oil, capric acid / Plant-derived hydrocarbon oils such as capric acid triglycerides, jojoba oil or shea butter oil, fatty acid liquid triglycerides containing 4-10 carbon atoms;
Pure serine oil, isononyl isononanoate, isopropyl myristate, 2-ethylhexyl palmitate, 2-octyldodecyl stearate, 2-octyldodecyl erucate or isostearyl isostearate; isostearyl lactic acid, octyl hydroxystearate, octyl hydroxystearate. Hydrolated esters such as dodecyl, diisostearyl malate, triisocetyl citrate or heptanate of fatty alcohols, octanate or decanoate; polyol esters such as propylene glycol dioctanoate, neopentyl glycol diheptate and diethylene glycol diisononanoate; and pentaisostearate penta Oils or formulas RaCOORb and RaORb, such as pentaerythritol esters such as erythrityl (where Ra represents a residue of a fatty acid containing 8 to 29 carbon atoms and Rb contains 3 to 30 carbon atoms. Synthetic esters and ethers of especially fatty acids such as (representing branched or unbranched hydrocarbon chains);
Liquid paraffins that may or may not be volatile and their derivatives, such as petrolatum, polydecene, isohexadecane, isododecane or hydropolyisobutene such as Parleam® oil, substantially direct from minerals or synthetics. Chain or branched hydrocarbons;
8-26 carbons such as cetyl alcohol, stearyl alcohol and mixtures thereof (cetearyl alcohol), octyldodecanol, 2-butyloctanol, 2-hexyldecanol, 2-undecylpentadecanol, oleyl alcohol or linoleyl alcohol. Fat alcohol with atoms;
Alkoxy fatty alcohols, specifically ethoxylated fatty alcohols such as oleth-12, ceteales-12 and ceteares-20;
Fluorinated oils (perfluoromethylcyclopentane, perfluoro-1,3-dimethylcyclohexane; perfluoro-1,2-dimethylcyclobutane, dodecafluoropentane, tetradecafluorohexane, perfluoroalkanes such as bromoperfluorooctyl, nonafluoromethoxybutane, nona Fluoroethoxyisobutane, 4- (trifluoromethyl) perfluoromorpholin, etc .;
Silicone oil, specifically cyclopolydimethylsiloxane (cyclomethicone) such as cyclohexadimethylsiloxane and cyclooentadimethylsiloxane; including pendant alkyl, alkoxy or phenyl group or alkyl, alkoxy or phenyl group at the end of the silicone chain. Polydimethylsiloxanes, these groups are polydimethylsiloxanes with 2 to 24 carbon atoms; or phenyltrimethicone, phenyldimethicone, phenyl (trimethylsiloxy) diphenylsiloxane, diphenyldimethicone, diphenyl (methyldiphenyl) -tri. Phenylated silicones such as siloxane, (2-phenylethyl) trimethylsiloxysilate and polymethylphenylsiloxane;
Fatty acids containing 8-30 carbon atoms such as stearic acid, lauric acid, palmitic acid and oleic acid;
Lanolin, beeswax, carnauba wax or candelilla wax, paraffin, subcarbon wax or microcrystalline wax, synthetic wax, or lipophilic UV protection agents are also components that can form an oil phase. These components can be used alone or in combination of two or more.

Further, the composition of the present disclosure preferably contains an emulsifier. As the emulsifier, for example, an ingredient known in the field of cosmetics can be used. More specifically, for example, glycerin fatty acid ester, organic acid monoglyceride (particularly fatty acid monoglyceride), polyglycerin fatty acid ester, propylene glycol fatty acid ester, polyglycerin condensed ricinoleic acid ester, sorbitan fatty acid ester, sucrose fatty acid ester, lecithin, enzymatic decomposition. Recitin and the like can be preferably used. Of these, fatty acid monoglycerides are preferable, and linear or branched chain fatty acids having 8 to 20 carbon atoms (8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20) are preferable. A monoester of (straight chain fatty acid) and glycerin is preferable.

The composition of the present disclosure is not particularly limited, but preferably contains 5 to 30% by mass of an ultraviolet protective agent. The upper or lower limit of the range is, for example, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26. , 27, 28, or 29% by weight. For example, the range may be 6 to 29% by mass.

The composition of the present disclosure is not particularly limited, but the aqueous phase (W phase) is preferably 70% by mass or more, and more preferably 71, 72, 73, 74, or 75% by mass or more.

Further, the composition of the present disclosure may contain silica.

The composition of the present disclosure is prepared, for example, by mixing a component (oil phase component) to be contained in the oil phase and the polymer of the present disclosure to prepare a polymer dispersion composition, which is further contained in the aqueous phase. It can be obtained by adding a component (aqueous phase component) and, if necessary, an emulsifier and further mixing to prepare an O / W type emulsion composition.

The composition of the present disclosure has significantly improved emulsion stability as compared with the conventional O / W type emulsion composition. For example, in the composition of the present disclosure, when 100 g thereof is centrifuged at 2000 rpm at 25 ° C. for 10 minutes, the amount of liquid to be separated is preferably substantially less than 3 g, and 2.5 g or less, 2 g or less, 1 It is more preferably 5.5 g or less, 1 g or less, or 0.5 g or less, and further preferably 0.1 g or less.

Further, the composition of the present disclosure preferably has a viscosity of, for example, 8000 mPa · s or more, and more preferably about 8000 to 35000 mPa · s. The upper or lower limit of the range is, for example, 9000, 10000, 11000, 12000, 13000, 14000, 15000, 16000, 17000, 18000, 19000, 20000, 21000, 22000, 23000, 24000, 25000, 26000, 27000, 28000, It may be 29000, 30000, 31000, 32000, 33000, or 34000 mPa · s. For example, the range may be 10,000 to 30,000 mPa · s. The viscosity is a value measured at room temperature (25 ° C.) using a B-type viscometer manufactured by BrookField with a rotation speed of 20 rpm.

In addition, in this specification, "includes" also includes "consisting of" and "consisting of" (The term "comprising" includes "consisting essentially of" and "consisting of."). In addition, the present disclosure includes all combinations of the constituent elements described herein.

Further, the various characteristics (property, structure, function, etc.) described for each embodiment of the present disclosure described above may be combined in any way in specifying the subject matter included in the present disclosure. That is, the present disclosure includes all subjects consisting of any combination of each of the combinable properties described herein.

Hereinafter, embodiments of the present disclosure will be described in more detail with reference to examples, but the embodiments of the present disclosure are not limited to the following examples.

Preparation of Polymer Composition [Production Example 1]
A stirrer, a reflux condenser and a dropping funnel were attached to a 300 mL separable flask. Acrylic acid and water were placed in this separable flask to prepare 92 g of an 80.5% by mass acrylic acid aqueous solution. While cooling the acrylic acid aqueous solution, 147.7 g of a 20.9 mass% sodium hydroxide aqueous solution was added dropwise to neutralize the aqueous solution. Further, 0.074 g (0.274 mmol) of potassium persulfate as an initiator was added to prepare an aqueous ethylenically unsaturated carboxylic acid monomer.

Separately, 356 g of n-heptane was placed in a 2 L separable flask equipped with a stirrer, a reflux cooling tube, a dropping funnel and a nitrogen gas introduction tube, and as a polymer-based dispersant, both maleic anhydride-modified ethylene and propylene were added. 0.736 g of a polymer (manufactured by Mitsui Kagaku Co., Ltd., High Wax 1105A) was added, and this was dispersed and dissolved in n-heptane. The previously prepared ethylenically unsaturated carboxylic acid monomer aqueous solution is added thereto, and then sucrose stearic acid ester (surfactant, manufactured by Mitsubishi Chemical Foods Co., Ltd., Ryoto Sugar Ester) is added to 6.62 g of n-heptane. S-370, HLB value: 3) A surfactant solution obtained by heating and dissolving 0.736 g was added to a separable flask. Then, in order to remove the atmosphere in the reaction vessel, the raw materials, and the oxygen present in the solvent, nitrogen gas is blown into the solution to replace the nitrogen in the system, and the bath temperature is maintained at 70 ° C. Polymerization was carried out over time.

After that, the temperature of the reaction solution was raised in an oil bath at 125 ° C., and 120 g of water was taken out of the system while refluxing n-heptane. Then, 7.27 g (ethylene glycol diglycidyl ether: 0.835 mmol) of 2% by mass of an ethylene glycol diglycidyl ether aqueous solution was added to the flask as a cross-linking agent, and then the mixture was kept at 83 ° C. for 2 hours.

After completion of the polymerization, water and n-heptane were distilled off to obtain a powder of a water-absorbent resin which is a polymer of acrylic acid and a sodium salt thereof and which is a polymer crosslinked with ethylene glycol diglycidyl ether. After passing this water-absorbent resin powder through a sieve having an opening of 850 μm, 2.0% by mass of amorphous silica (Tokuseal NP-S manufactured by Oriental Silicas Corporation) based on the total mass of the water-absorbent resin is applied. By mixing with the water-absorbent resin, 90.3 g of a water-absorbent resin composition containing amorphous silica was obtained.

The average particle size of the obtained water-absorbent resin after swelling with water was 200 μm. The average particle size is a medium particle size of the volume average particle size measured by a laser diffraction method (using a laser diffraction type particle size distribution measuring device: SALD-2300 (manufactured by Shimadzu Corporation)). The same applies to the following.

[Manufacturing Example 2]
<Synthesis of water-soluble sucrose allyl ether>
A stirrer, a reflux condenser and a dropping funnel were attached to a 1000 mL separable flask. In this separable flask, 48 g (1.2 mol) of sodium hydroxide was dissolved in 144 g of water. 136.8 g (0.4 mol) of sucrose was added thereto, and the mixture was stirred at 70 to 85 ° C. for 120 minutes to prepare an aqueous alkaline sucrose solution. To this alkaline sucrose aqueous solution, 145.2 g (1.2 mol) of allyl bromide was added dropwise at 70 to 85 ° C. over 1.5 hours, and then aged at 80 ° C. for 3 hours to sucrose. Was allyl etherified. After cooling, 440 g of water was added, and excess oil was separated with a separating funnel to obtain a crude sucrose allyl ether aqueous solution. Hydrochloric acid was added to this crude sucrose allyl ether aqueous solution to adjust the pH to 6 to 8, and then water was removed using a rotary evaporator until the mass of the aqueous solution reached 480 g. Then, 200 g of ethanol was added to precipitate salts such as sodium bromide as a by-product, and the precipitate was removed from the aqueous solution by filtration. Further, excess water was removed from the aqueous solution using an evaporator to obtain 166 g of purified water-soluble sucrose allyl ether having an etherification degree of 2.4.

<Synthesis of water-absorbent resin>
A stirrer, a reflux condenser and a dropping funnel were attached to a 500 mL separable flask. 72 g of acrylic acid and water were placed in this separable flask to prepare 90 g of an 80% by mass acrylic acid aqueous solution. While cooling the acrylic acid aqueous solution, 54 g of a 30% by mass sodium hydroxide aqueous solution was added dropwise to neutralize the aqueous solution. Further, 56 g of ion-exchanged water, 0.32 g of the above-mentioned water-soluble sucrose allyl ether as a cross-linking agent (0.35% by mass with respect to an aqueous acrylic acid solution), and 2,2'-azobis (2-methylpropion) as an initiator. Aqueous ethylenically unsaturated carboxylic acid monomer was prepared by adding 0.04 g of amidin) dihydrochloride (V-50 manufactured by Wako Pure Chemical Industries, Ltd.).

Separately, 330 g of n-heptane was placed in a 2 L separable flask equipped with a stirrer, a reflux condenser, a dropping funnel and a nitrogen gas introduction tube, and the surfactant sorbitan monostearate (Nichiyu Co., Ltd.) , Nonion SP-60R) 2.7 g was added, and this was dispersed and dissolved in n-heptane. The previously prepared ethylenically unsaturated carboxylic acid monomer aqueous solution was added thereto. The bath temperature was maintained at 60 ° C. over 1 hour while nitrogen gas was blown into the solution to replace the nitrogen in the system in order to remove the atmosphere in the reaction vessel, the raw materials and the oxygen present in the solvent. And polymerized. After completion of the polymerization, water and n-heptane were distilled off to obtain a powder of a water-absorbent resin which is a polymer of acrylic acid and a sodium salt thereof and which is a polymer crosslinked with water-soluble sucrose allyl ether. ..

By mixing 0.7% by mass of amorphous silica (Tokuseal NP-S manufactured by Oriental Silicas Corporation) with the water-absorbent resin based on the total mass of this water-absorbent resin, water absorption containing amorphous silica is performed. 90 g of the sex resin composition was obtained.

The average particle size of the obtained water-absorbent resin after swelling with water was 120 μm.

[Manufacturing Example 3]
A stirrer, a reflux condenser and a dropping funnel were attached to a 300 mL separable flask. Acrylic acid and water were placed in this separable flask to prepare 92 g of an 80.5% by mass acrylic acid aqueous solution. While cooling the acrylic acid aqueous solution, 147.7 g of a 20.9 mass% sodium hydroxide aqueous solution was added dropwise to neutralize the aqueous solution. Further, 0.018 g (0.103 mmol) of ethylene glycol diglycidyl ether as a cross-linking agent and 0.083 g (0.307 mmol) of potassium persulfate as an initiator are added, and the first-stage ethylenity-free property is added. A saturated aqueous solution of carboxylic acid monomer was prepared.

Separately, 356 g of n-heptane was placed in a 2 L separable flask equipped with a stirrer, a reflux cooling tube, a dropping funnel and a nitrogen gas introduction tube, and as a polymer-based dispersant, both maleic anhydride-modified ethylene and propylene were added. 0.736 g of a polymer (manufactured by Mitsui Kagaku Co., Ltd., high wax 1105A) was added, and this was dispersed and dissolved in n-heptane. The previously prepared ethylenically unsaturated carboxylic acid monomer aqueous solution is added thereto, and then sucrose stearic acid ester (surfactant, manufactured by Mitsubishi Chemical Foods Co., Ltd., Ryoto Sugar Ester) is added to 6.62 g of n-heptane. S-370, HLB value: 3) A surfactant solution obtained by heating and dissolving 0.736 g was added to a separable flask. Then, in order to remove the atmosphere in the reaction vessel, the raw materials, and the oxygen present in the solvent, nitrogen gas is blown into the solution to replace the nitrogen in the system, and the bath temperature is maintained at 70 ° C. The first-stage polymerized slurry liquid was obtained over time.

Next, a stirrer, a reflux condenser and a dropping funnel were attached to another 300 mL separable flask, and 128.8 g (acrylic acid: 1.44 mol) of an 80.5 mass% acrylic acid aqueous solution was added. Subsequently, while cooling the acrylic acid aqueous solution, 159.0 g of a 27% by mass sodium hydroxide aqueous solution was added dropwise to neutralize the aqueous solution. Then, 0.116 g (0.429 mmol) of potassium persulfate was added as an initiator, and 0.026 g (0.149 mmol) of ethylene glycol diglycidyl ether was added as a cross-linking agent. A saturated carboxylic acid monomer aqueous solution was prepared.

Next, after cooling the inside of the above-mentioned separable flask to 60 ° C. while stirring with a stirrer, the entire amount of the above-mentioned second-stage aqueous liquid was added to the above-mentioned first-stage polymerized slurry liquid. Subsequently, after replacing the inside of the system with nitrogen, the flask was again immersed in a water bath at 70 ° C. to raise the temperature, and the polymerization reaction was carried out for 1 hour to obtain a second-stage hydrogel polymer.

After that, the temperature of the reaction solution was raised in an oil bath at 125 ° C., and 250 g of water was withdrawn from the system while refluxing n-heptane. Then, 7.27 g (ethylene glycol diglycidyl ether: 0.835 mmol) of 2% by mass of an ethylene glycol diglycidyl ether aqueous solution was added to the flask as a cross-linking agent, and then the mixture was kept at 83 ° C. for 2 hours.

After completion of the polymerization, water and n-heptane were distilled off to obtain a powder of a water-absorbent resin which is a polymer of acrylic acid and a sodium salt thereof and which is a polymer crosslinked with ethylene glycol diglycidyl ether. After passing this water-absorbent resin powder through a sieve having an opening of 850 μm, 2.0% by mass of amorphous silica (Tokuseal NP-S manufactured by Oriental Silicas Corporation) based on the total mass of the water-absorbent resin is applied. By mixing with the water-absorbent resin, 218.3 g of a water-absorbent resin composition containing amorphous silica was obtained.

The average particle size of the obtained water-absorbent resin after swelling with water was 660 μm.

Examination of the characteristics of the water-absorbent resin The "slope of steady flow viscosity" and "yield stress / yield strain balance" of each 1% by mass aqueous solution of the water-absorbent resin composition were measured as follows. In the following studies, a water-absorbent resin composition prepared with reference to the production method of the above-mentioned production example was used as the polymer. More specifically, the water-absorbent resin composition prepared with reference to the production method of Production Example 1 is designated as polymer A, and the water-absorbent resin composition prepared with reference to the production method of Production Example 2 is designated as polymer B. The water-absorbent resin composition prepared with reference to the above-mentioned production method of Production Example 3 was used as the polymer C, respectively.

A 1% by mass aqueous solution was prepared for the polymers A, B, or C, and the steady flow viscosity was measured with a rheometer. More specifically, a rheometer manufactured by TA Instruments is used, and an aluminum parallel plate (diameter: 60 mm, Gap: 1000 μm) is used to obtain a steady flow viscosity in the range of a shear rate of 0.000001 to 1,000 s ^-1 . It was measured.

Then, a log-log graph of x-axis: shear rate (s ^-1 ) and y-axis: viscosity (Pa · s) is created for the slope of the steady flow viscosity in the range of shear rate 0.1 to 1,000 s ^-1 . Then, it was obtained by reading the slope from the approximate straight line of the plot.

In addition, a logarithmic graph of x-axis: stress (Pa) and y-axis: strain (%) is created, and the stress (Pa) and strain (%) at the point where the slope of the plot changes abruptly are read. The stress was defined as the yield stress, the strain was defined as the yield strain, and the value obtained by dividing the yield stress (Pa) value by the yield strain (%) value was defined as the “yield stress / yield strain balance”.

The measurement results are shown in graphs in FIGS. 1 and 2.

Further, an aqueous solution containing 1% by mass of the polymer A, B or C and 0.5% by mass of sodium chloride was prepared and sieved with an opening of 75 μm. The mass of polymer remaining on the sieve was measured. Then, it was calculated how much the mass of the polymer remaining on the sieve was the mass% of the mass of the polymer contained in the aqueous solution. It can be said that the calculation result indicates the salt tolerance of each polymer (the smaller the value, the lower the salt tolerance). The calculation results (salt tolerance) and the results of the above examination are summarized in the following table. It should be noted that when the polymer is applied to the skin, the one having low salt tolerance has a sharp decrease in viscosity due to the influence of salt on the skin, and a refreshing tactile sensation can be obtained.

It can be said that the smaller the "particle size after water swelling", the better the feel when applied to the skin without the graininess. Further, it can be said that the larger the values of "slope of steady flow viscosity" and "balance of yield stress / yield strain", the stronger the refreshing feeling when the polymer aqueous solution is applied to the skin. In addition, it can be said that the smaller the numerical value, the stronger the refreshing feeling as the result of the "salt tolerance evaluation".

Preparation and Evaluation of O / W Emulsion Composition According to the composition shown in Table 2, the UV absorber (oil phase component) and the polymer composition are mixed at 75 ° C. to prepare a polymer dispersion composition, which is further prepared. A polyhydric alcohol, an emulsifier, and ion-exchanged water were mixed at 75 ° C., emulsified, and allowed to cool to room temperature with stirring to prepare an O / W type emulsion composition (sunscreen composition). The unit of the numerical value of each component in Table 2 is g (gram).

Each O / W type emulsion composition (100 g) obtained was transferred to a 100 ml centrifuge tube, centrifuged at 2000 rpm at 25 ° C. for 10 minutes, and then the weight of the separated liquid was measured. It can be said that the smaller the amount of the separated liquid, the higher the stability of the composition. Moreover, when the panelists applied each O / W type emulsion composition to their own skin, there was no sliminess and the feeling of freshness was good. These results are also shown in Table 2.

The viscosities of the compositions of Example 1a, Example 2a, and Comparative Example 3a were measured and found to be 22800 mPa · s, 24600 mPa · s, and 7700 mPa · s, respectively. Further, the compositions of Examples 1a and 2a have higher emulsification stability than the composition of Comparative Example 3a, and the compositions of Examples 1b and 2b have higher emulsification stability than the composition of Comparative Example 3b. rice field. The emulsification stability was examined by confirming the weight of the amount of liquid separated after centrifugation.

The viscosity is a value measured at room temperature (25 ° C.) using a B-type viscometer manufactured by BrookField with a rotation speed of 20 rpm.

Claims

An O / W type emulsion composition containing a water-absorbent polymer.
The water-absorbent polymer has the following conditions (A), (B), and (C):
(A): The particle size after water swelling is 100 to 600 μm (B): At least one of the following (B-1) and (B-2) is satisfied (B-1): 1% by mass aqueous solution of polymer. The slope in the log-log graph of the steady flow viscosity of -1 or more and less than 0 (in the range of shear velocity 0.1 to 1,000 s -1 )
(B-2): Balance of yield stress / yield strain of 1% by mass aqueous solution of polymer is 10 or more (C): When an aqueous solution of 1% by mass of polymer and 0.5% by mass of sodium chloride is sieved with an opening of 75 μm. A polymer satisfying that the amount of polymer remaining on the sieve is 50% by mass or less of the amount of the aqueous solution-containing polymer.
Composition.
The composition according to claim 1, further comprising an organic UV protection agent.
The composition according to claim 2, wherein the organic UV protection agent is a lipophilic organic UV protection agent.
The composition according to any one of claims 1 to 3, wherein the water-absorbent polymer is a polymer obtained by polymerizing a water-soluble unsaturated carboxylic acid monomer in the presence of a cross-linking agent.
The composition according to claim 4, wherein the cross-linking agent is at least one selected from the group consisting of water-soluble sucrose allyl ether, ethylene glycol diglycidyl ether, and pentaerythritol allyl ether.
The composition according to any one of claims 1 to 5, further comprising silica.