JP3274992B2 - Polymer emulsion and method for producing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to chitosan useful for skin cosmetics, hair cosmetics, pharmaceuticals, fiber treatment agents, deodorants, fragrances, cement additives, coating materials, bactericidal / bacteriostatic agents, agricultural chemicals, etc. The present invention relates to a polymer emulsion containing the same and a method for producing the same.

[0002]

BACKGROUND OF THE INVENTION Chitosan is a basic polysaccharide obtained by treating chitin present in the crust of crustaceans such as crabs and shrimps with concentrated alkali and deacetylating it. This chitosan is used for various adsorbents, medical carriers,
Research and development as antibacterial agents are being carried out. However, chitosan was hardly dissolved by itself except in an acidic aqueous solution due to strong hydrogen bonding between molecules, and when it was made into an aqueous solution, the viscosity of the solution was extremely high and handling was difficult. Therefore, Japanese Patent Application Laid-Open No.
No. 30722, JP-A-62-62827, JP-A-62-70
JP-A-63-20302 discloses a method of dissolving chitosan in an acid and then dropping this solution into an alkali coagulation solution as disclosed in JP-A-63-20792 and JP-A-62-279201.
As disclosed in JP-A-63-17902 and JP-A-63-210101, there is a method of mechanically treating a chitosan solution or a chitosan dispersion. However, all of the particles can only obtain particles of several tens μm to several hundred μm or more and are not dispersed in water.

Accordingly, an object of the present invention is to obtain a polymer emulsion in which small-sized polymer particles containing chitosan are dispersed in water.

[0004]

According to the present invention, there is provided a polymer emulsion having a core portion and a shell portion and containing polymer particles having an average particle size of 30 μm or less, wherein the shell portion comprises chitosan (a) and a polymer. A polymer emulsion comprising a polymer (b) of an organic acid or a salt thereof having a hydrophobic vinyl group as a constituent component and a polymer (c) of a hydrophobic monomer as a core component, and a process for producing the same. Is provided.

The present invention also provides a polymer emulsion having a core portion and a shell portion and containing polymer particles having an average particle size of 30 μm or less, wherein the shell portion has chitosan (a).
And polymers of organic acids or salts thereof having a reactive vinyl group
(b) is a constituent component, the core of which is a polymer of a hydrophobic monomer
It is intended to provide a polymer emulsion comprising a mixture of (c) and a non-polymerizable hydrophobic substance (d) as a component, and a method for producing the same.

[0006] In the present invention, the polymer particles are
Polymer microsphere.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The polymer emulsion of the present invention can be produced by the following production methods (1) and (2). (1) Chitosan (a), organic acid having a reactive vinyl group or its salt (e), hydrophobic monomer (f), and oil-soluble polymerization initiator
(g) Further, if necessary, a non-polymerizable hydrophobic substance (d) obtained by emulsifying and dispersing in water, monomer droplets having an average particle size of 10 μm or less are polymerized, and the core portion and the shell portion of the polymer particles are formed. How to form.

(2) A polymer particle (i) having an average particle size of 10 μm or less compatible with the hydrophobic monomer (f) is added to the hydrophobic monomer (f) and, if necessary, a non-polymerizable hydrophobic substance (d). Swelling, and further adding an aqueous solution of chitosan (a) and an organic acid having a reactive vinyl group or a salt thereof (e), and for the obtained swollen polymer particles, an oil-soluble polymerization initiator (g) The polymerization of the core and shell in the presence of a water-soluble polymerization initiator (h).

[Chitosan (a)] Chitosan (a) used in the present invention is a deacetylated product of chitin having a (1 → 4) -2-acetamido-2-deoxy-β-D-glucan structure. It has a (1 → 4) -2-amino-2-deoxy-β-D-glucan structure, and in the present invention, a part of the deacetylated amino group or one of the hydroxyl groups in the same molecule. Also included are chitosan derivatives whose parts are chemically modified by acylation, etherification, esterification, and other reactions. In general, naturally occurring chitin has a degree of deacetylation of 30% or more as chitosan used in the present invention because a part of an acetamido group is an amino group which is not acetylated.

[Organic acid having a reactive vinyl group or its salt (e)] The organic acid having a reactive vinyl group used in the present invention can be dissolved in chitosan to form an aqueous solution.
It is a water-soluble organic acid having at least one reactive vinyl group and at least one acidic group in the molecule. Specifically, unsaturated carboxylic acid monomers such as acrylic acid, methacrylic acid, crotonic acid, itaconic acid, and maleic acid, styrenesulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid, and 3-sulfopropyl (meth) Acrylic acid esters,
Unsaturated sulfonic acid monomers such as bis (3-sulfopropyl) itaconate and vinyl sulfonic acid, vinyl phosphate, bis (methacryloxyethyl) phosphate, diphenyl-2-acryloyloxyethyl phosphate, diphenyl-2-methacrylic acid Unsaturated phosphate monomers such as loyloxyethyl phosphate, dibutyl-2-acryloyloxyethyl phosphate, dibutyl-2-methacryloyloxyethyl phosphate and dioctyl-2- (meth) acryloyloxyethyl phosphate; and the like. Can be used alone or in combination. Among these, unsaturated carboxylic acid monomers having a relatively low acidity are preferable, and methacrylic acid having a low acidity of the polymer is particularly preferable. Examples of the salt of the organic acid having a reactive vinyl group include alkali metal (Na, K, etc.) salts and ammonium salts.

It is also possible to arbitrarily mix various acids with these organic acids having a reactive vinyl group or salts thereof. At this time, the types of acids to be mixed include inorganic acids such as hydrochloric acid, sulfuric acid, and phosphoric acid, formic acid, acetic acid, lactic acid, citric acid, tartaric acid, succinic acid, malic acid, oxalic acid, glycolic acid, dichloric acid, and trifluoroacid. Organic acids such as acetic acid are exemplified.

[Hydrophobic monomer (f)] The hydrophobic monomer (f) used in the present invention is copolymerizable with the above-mentioned organic acid having a reactive vinyl group or its salt (e) and has a hydrophobic property. There is no particular limitation as long as it is present, but preferred are those having a solubility in water of 100 g of less than 0.1 g at 20 ° C. Examples of such hydrophobic monomers include, for example, styrene, divinylbenzene, butyl acrylate, 2-ethylhexyl acrylate, cyclohexyl acrylate, decyl acrylate, lauryl acrylate, dodecenyl acrylate,
Acrylates such as myristyl acrylate, palmityl acrylate, hexadecenyl acrylate, stearyl acrylate, octadecenyl acrylate, and behenyl acrylate, butyl methacrylate, and 2-methacrylic acid
Methacrylic esters such as ethylhexyl, cyclohexyl methacrylate, decyl methacrylate, lauryl methacrylate, dodecenyl methacrylate, myristyl methacrylate, palmityl methacrylate, hexadecenyl methacrylate, stearyl methacrylate, octadecenyl methacrylate, behenyl methacrylate, and trifluoroacetic acid Examples include fluorine-based monomers such as ethyl methacrylate, and silicone macromonomers. One or more of these hydrophobic monomers can be used.

[Oil-soluble polymerization initiator (g)] The oil-soluble polymerization initiator (g) used in the present invention is one which initiates addition polymerization of monomers by radical decomposition in the presence of heat or a reducing substance. In general, oil-soluble peroxides, azobis compounds, and the like are used. For example, organic peroxides such as lauroyl peroxide and benzoyl peroxide, 2,2′-azobisisobutyronitrile, 2,2′-azobis (2,4
-Dimethylvaleronitrile), 2,2'-azobis (2
-Methylbutyronitrile). One or more of these polymerization initiators can be used.

[Non-polymerizable hydrophobic substance (d)] The non-polymerizable hydrophobic substance (d) used in the present invention includes wax, fragrance, cooling sensation agent, warming sensation agent, plasticizer, chain transfer agent and the like. Is mentioned. In this case, by incorporating a fragrance, a cooling sensation agent or a warming sensation in the polymer particles, it is possible to maintain the fragrance and the medicinal effect for a long time. As wax, petroleum wax,
Natural waxes such as animal and vegetable waxes and processed natural waxes such as hydrides thereof, and synthetic waxes such as Fischer-Tropsch wax and polyethylene wax can be used.

The fragrance used in the present invention includes terpene hydrocarbons such as α-pinene, β-pinene, myrcene, limonene and 1,8-cineole, and hydrophobic fragrances such as amyl acetate and amyl propionate. For example, Japanese Unexamined Patent Publication
No.-32673, perfume described on page 3, upper left column, line 19 to lower left column, line 13). One or more of these can be used.

Examples of the cooling sensation agent used in the present invention include camphor, thymol, peppermint oil, peppermint oil, spearmint oil, 1-menthol, and menthol derivatives. Examples of the warming sensation agent include nonylate vanillylamide, capsaicin, ginglon, vanillyl butyl ether and natural extracts containing these as a main component, such as pepper extract (tincture), arnica tincture, ginger extract (tincture) and the like. And oleoresin having an effect. One or more of these can be used.

Examples of the plasticizer include phthalic acid diester, adipic acid diester, succinic acid diester, sebacic acid diester, abietic acid ester, caprylic acid ester, caproic acid ester, acetate ester, enanthate ester, myristate ester, citric acid ester. Esters such as acid esters; benzoic esters such as sucrose benzoate; phosphoric esters such as tricresyl phosphate; and diethylbenzene.

[Polymer Particle (i)] The polymer particle (i) used in the present invention is not particularly limited as long as it has a mean particle diameter of 10 μm or less, preferably 0.01 to 10 μm. Polymer emulsions, cationic polymer emulsions, nonionic polymer emulsions, polymer fine particles, microgels, and the like can be used. The composition of these polymer particles is not particularly limited, but those having high compatibility with the hydrophobic monomer (f) are desirable.

[Water-Soluble Polymerization Initiator (h)] The water-soluble polymerization initiator (h) used in the present invention is radically decomposed in the presence of heat or a reducing substance to initiate addition polymerization of a monomer. Water soluble peroxodisulfate, peroxide,
An azobis compound or the like is generally used. For example, peroxodisulfates such as potassium persulfate and ammonium persulfate; peroxides such as hydrogen peroxide and t-butyl hydroperoxide; 2,2′-azobis-2-amidinopropane salts (V-50); And azo compounds such as 4,4'-azobis-4-cyanopentanoic acid. If necessary, a redox initiator can be used in combination with a reducing agent.

[Production Method of Polymer Emulsion (1)] In this production method, the mixing ratio of chitosan (a) and an organic acid having a reactive vinyl group or a salt thereof (e) is such that an acid having no double bond is used. When used together, there is no particular limitation.
When an acid having no double bond is not used in combination, it is preferable to use 0.75 to 10-fold mol of an organic acid having a reactive vinyl group or a salt (e) thereof in terms of a monosaccharide unit of chitosan. If the molar ratio is less than 0.75 times, chitosan tends to be unable to completely dissolve in water.

Further, chitosan (a) and hydrophobic monomer (f)
The compounding ratio of is based on 100 parts by weight of the hydrophobic monomer (f),
It is desirable to use 1 to 5000 parts by weight, preferably 2 to 300 parts by weight of chitosan (a). If the amount of chitosan (a) is less than 1 part by weight based on 100 parts by weight of the hydrophobic monomer (f), the performance of chitosan tends not to be sufficiently exhibited,
On the other hand, if it exceeds 5000 parts by weight, the stability of the polymer emulsion tends to be impaired.

In the present production method, the oil-soluble polymerization initiator (g)
Is 0.05 to 10.0 with respect to 100 parts by weight of the hydrophobic monomer (f).
It is preferred to use in the range of parts by weight.

The polymerization in the present production method can be carried out in the presence or absence of a surfactant. Surfactants used include common anionic, cationic, nonionic and amphoteric surfactants. Examples of the anionic surfactant include dodecyl sulfate, dodecyl benzene sulfonate, and sulfate salt of polyoxyethylene nonylphenyl ether. Examples of the nonionic surfactant include polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, polyoxyethylene-polyoxypropylene block copolymer, and the like. Examples of the cationic surfactant include octadecyltrimethylammonium chloride. Examples of the amphoteric surfactant include betaine alkyldimethylaminoacetate and 2-alkyl-N-carboxy-N-hydroxyimidazolinium betaine.

However, since amphoteric ions are present in the polymer particles, nonionic surfactants are desirable in view of the stability of the particles. The amount of the surfactant used is not particularly limited, but it is preferable to use the surfactant in the range of 0.1 to 20 parts by weight based on 100 parts by weight of the hydrophobic monomer (f).

Further, in the present production method, a water-soluble polymer can be used as an emulsifier. As the water-soluble polymer, for example, polyvinyl alcohol and its derivatives,
Examples include starch and its derivatives, cellulose derivatives and the like. One or more of these surfactants and water-soluble polymers can be used.

Further, in the present production method, the hydrophobic monomer
When emulsifying (f), the non-polymerizable hydrophobic substance (d) can be used by mixing with the hydrophobic monomer (f). In this case, the amount of the non-polymerizable hydrophobic substance (d) is preferably 0 to 90% by weight, and more preferably 1 to 50% by weight, based on the hydrophobic monomer (f) forming the core.

Further, when emulsifying the hydrophobic monomer (f), the hydrophilic monomer (j) can be used by mixing with the hydrophobic monomer (f). In this case, the amount of the hydrophilic monomer (j) used is the amount of the hydrophobic monomer (f) forming the core.
0 to 50% by weight, preferably 0 to 20% by weight, When the content of the hydrophilic monomer (j) exceeds 50% by weight, the occurrence of emulsion polymerization becomes severe, and it is difficult to synthesize an emulsion having good stability.

In this case, the hydrophilic monomer (j) to be used can be copolymerized with the organic acid having a reactive vinyl group or its salt (e) and the hydrophobic monomer (f). Although not particularly limited, water is preferably 1
The solubility in 00g is 0.1g or more at 20 ° C. Such hydrophilic monomers include, for example, methyl acrylate, hydroxyethyl acrylate, hydroxypropyl acrylate, polyethylene glycol monoacrylate, glycidyl acrylate, methyl methacrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, polyethylene glycol monoacrylate Examples include methacrylate, glycidyl methacrylate, acrylamide, methacrylamide, N, N-dimethylacrylamide, diacetone acrylamide, and vinyl acetate. One or more of these hydrophilic monomers can be used.

In the present production method, the above-described chitosan (a)
, An organic acid having a reactive vinyl group or a salt thereof (e), a hydrophobic monomer (f), an oil-soluble polymerization initiator (g), and, if necessary, a non-polymerizable hydrophobic substance (d), and By emulsifying by mechanical stirring using an emulsifying device, an O / W emulsion containing monomer droplets having an average particle diameter of 10 μm or less is prepared. In this case, if the average particle size of the monomer droplets is larger than 10 μm, the average particle size of the polymer particles of the obtained polymer emulsion exceeds 30 μm, which is not preferable.

The emulsifying apparatus used here includes an ultrasonic homogenizer, a homomixer, a milder, an attritor, a (ultra) high-pressure homogenizer, a nanomizer system, a membrane emulsifying apparatus, and the like. In addition, it is desirable to select the solid content concentration at the time of emulsification in the range of 1 to 60% by weight.

In the present production method, the O / W emulsion prepared as described above is heated and polymerized. The polymerization temperature varies depending on the type of the initiator, but is suitably in the range of about 40 ° C to 90 ° C. The polymerization time varies depending on the type of the monomer, the type of the polymerization initiator, and the reaction temperature, but is generally from 1 hour to 24 hours. A water-soluble polymerization initiator may be added during the polymerization of the core portion or after the polymerization of the core portion in order to polymerize the organic acid or the salt (e) thereof having a reactive vinyl group in the shell portion in the monomer oil droplets.

The water-soluble polymerization initiator used in this case is the same as the above-mentioned water-soluble polymerization initiator (h). The use amount of the water-soluble polymerization initiator is preferably in the range of 0.05 to 20% by weight based on the organic acid or its salt (e). Further, in order to increase the chitosan content in the polymer particles, an aqueous solution of chitosan (a) and an organic acid having a reactive vinyl group or a salt thereof (e) may be further added during polymerization.

[Production Method of Polymer Emulsion (2)] In this production method, polymer particles (i) having an average particle size of 10 μm or less are swollen with a hydrophobic monomer (f), or polymer particles having an average particle size of 10 μm or less. (i) is a non-polymerizable hydrophobic substance
(d) and the hydrophobic monomer (f),
This is a method in which (a) and an organic acid having a reactive vinyl group or a salt thereof (e) are used as a protective colloid and polymerization is carried out in the presence of a polymerization initiator. In this case, the average particle size of the polymer particles (i) is 10
If it is larger than μm, the average particle size of the polymer particles of the obtained polymer emulsion exceeds 30 μm, which is not preferable.

In the present production method, the hydrophobic monomer (f) is preferably used in an amount of 5 to 20 in terms of solid content relative to the polymer particles (i).
It is desirable to use 000% by weight, more preferably 10 to 1000% by weight. When the amount of the hydrophobic monomer is less than 5% by weight,
The connection between the core and shell tends to be insufficient,
If it exceeds 0000% by weight, the stability becomes insufficient.

The method for swelling the polymer particles (i) with the hydrophobic monomer (f), or optionally with the non-polymerizable hydrophobic substance (d) and the hydrophobic monomer (f) is not particularly limited. Hydrophobic monomer in polymer particles (i)
(f), a method of emulsifying the hydrophobic monomer (f) or the hydrophobic monomer (f) and a water-soluble organic solvent using a surfactant, and adding the resultant to the polymer particles (i) dispersed in water. Can be Also in this case, the hydrophobic monomer
A non-polymerizable hydrophobic substance (d) may be added together with (f), and the amount of the non-polymerizable hydrophobic substance (d) used is from 0 to 90% by weight, preferably 1 to 90% by weight, based on the hydrophobic monomer (f). ~ 50% by weight is desirable.

When the polymer particles swollen by the hydrophobic monomer (f) or the non-polymerizable hydrophobic substance (d) and the hydrophobic monomer (f) are dispersed in water, a surfactant may be used. . The surfactant used here may be any of anionic, cationic and nonionic surfactants. The amount used is preferably 1 to 50% by weight based on the polymer particles.

In the present production method, after the polymer particles (i) are swollen with the hydrophobic monomer (f) or the non-polymerizable hydrophobic substance (d) and the hydrophobic monomer (f) as described above, Further, an aqueous solution of chitosan (a) and an organic acid having a reactive vinyl group or a salt thereof (e) is added, and the resulting swollen polymer particles are subjected to an oil-soluble polymerization initiator (g), and further, if necessary, to a water-soluble polymerization initiator. The polymerization of the core part and the shell part is carried out in the presence of the agent (h). In this production method, the amounts of chitosan (a), the organic acid having a reactive vinyl group or its salt (e), and the polymerization initiator are substantially the same as those in the production method (1).

The chitosan-containing polymer emulsion obtained by the above production methods (1) and (2) can be neutralized with a base. As the base used here, ammonia, methylamine, ethylamine, propylamine, butylamine, isobutylamine, hexylamine, octylamine, amino-modified silicone, ethylenediamine, propylenediamine, butylenediamine, sodium hydroxide, potassium hydroxide, water Examples include calcium oxide, sodium carbonate, sodium alkoxide, and potassium alkoxide. The amount of the base added is preferably 0.1 to 2.0 mol%, particularly preferably 0.6 to 1.2 mol%, based on the organic acid polymer in the emulsion.

[Polymer Particles in Polymer Emulsion] The polymer particles in the polymer emulsion obtained by the present invention have a particle size of 30 μm or less, preferably 0.01 to 30 μm.
m, more preferably from 0.05 to 10 μm.
If the average particle size is larger than 30 μm, the storage stability of the emulsion will be poor. In the present invention, the average particle size of the polymer particles is measured by a laser diffraction type particle size distribution analyzer (LA-910).
, Manufactured by HORIBA).

The polymer particles in the polymer emulsion obtained by the present invention have a core portion and a shell portion, and the shell portion is a polymer (b) of an organic acid or a salt thereof having chitosan (a) and a reactive vinyl group. ) As a constituent, and a polymer (c) having a core having a hydrophobic monomer as a constituent.

Such a polymer emulsion of the present invention has good water dispersion stability, and is suitable for skin cosmetics, hair cosmetics,
Useful for pharmaceuticals, textile treatments, deodorants, fragrances, cement additives, coating materials, bactericidal / bacteriostatic agents, pesticides and the like.

[0042]

Example 1 45 g of 2.5 g of commercially available chitosan (SK-10, manufactured by Koyo Chemical Co., Ltd., degree of deacetylation: 85-88%, weight average molecular weight: 130000)
g of water was added, and 1.0 g of methacrylic acid (equimolar amount based on the monosaccharide unit of chitosan) was added thereto, and the mixture was dissolved with stirring at 60 ° C. to prepare a chitosan / methacrylic acid aqueous solution. Next, 50 g of stearyl methacrylate and 0.5 g of lauroyl peroxide were dissolved in a 1 liter glass beaker, ion-exchanged water 500 g, Emulgen 420 (Kao Corporation)
(Nonionic surfactant) (5 g) and 50 g of the previously prepared aqueous solution of chitosan / methacrylic acid were added, and the mixture was treated with an ultrasonic homogenizer (manufactured by Nippon Seiki Seisakusho) for 30 minutes while stirring to obtain an emulsion having an average particle size of 1.12 μm. I got something. This emulsified product was transferred to a 1-liter glass reactor equipped with a stirrer, a cooler and a nitrogen inlet tube, and after purging with nitrogen, the mixture was heated with stirring to bring the internal temperature to 75 ° C. After polymerization for 2 hours with stirring, a solution prepared by dissolving 0.1 g of ammonium persulfate in 10 g of water was added, and the reaction was further continued for 2 hours to obtain a polymer emulsion.

The obtained polymer emulsion was freeze-dried and subjected to SEM (the dried sample was subjected to gold vapor deposition to obtain S
EM observation was performed. SUPER SCAN-220 (registered trademark): manufactured by Shimadzu Corp.) and TEM (dried sample is negatively stained, and a cross section is cut out with a microtome.
Observed. JEM2000FX (registered trademark): made by JEOL Ltd.)
As a result, it was confirmed that the polymer particles were spherical, the shell portion was a layer derived from hydrophilic chitosan, and the core portion had a core-shell structure composed of poly (stearyl methacrylate). In addition, the following Examples 2-6, 8-11 and
15 to 17, it was confirmed that the polymer particles had the same structure.

Example 2 A polymer emulsion was obtained in the same manner as in Example 1 except that 1.0 g of methacrylic acid was replaced by 2.0 g of methacrylic acid (2.0 times the molar amount with respect to the chitosan unit).

Example 3 A polymer emulsion was obtained in the same manner as in Example 1 except that 3.0 g of methacrylic acid (3.0 times by mol relative to the chitosan unit) was used instead of 1.0 g of methacrylic acid.

Example 4 A polymer emulsion was obtained in the same manner as in Example 1, except that 0.5 g of Emulgen 420 was used instead of 5 g of Emulgen 420.

Example 5 The procedure of Example 1 was repeated, except that 50 g of stearyl methacrylate was used.
25 g of stearyl methacrylate and 25 g of HNP-9 (Nippon Seisaku; paraffin wax) were melt-mixed, and a polymer emulsion was obtained in the same manner as in Example 1.

Example 6 A monomer emulsion was prepared in the same manner as in Example 1, and the internal temperature was heated to 75 ° C. using the same reactor as in Example 1. One hour after the reaction, 150 g of an aqueous chitosan / methacrylic acid solution prepared in the same manner as in Example 1 was added dropwise over 2 hours. Then one
Polymerization was carried out for 10 hours, and a solution prepared by dissolving 0.1 g of potassium persulfate in 10 g of ion-exchanged water was added, and polymerization was further carried out for 2 hours.
A polymer emulsion was obtained.

Example 7 In Example 1, 50 g of stearyl methacrylate was used instead of 50 g.
Using g of lauryl methacrylate, a polymer emulsion was obtained in the same manner as in Example 1. In the same manner as in Example 1, it was confirmed that the polymer particles were spherical, the shell portion was a layer derived from hydrophilic chitosan, and the core portion had a core-shell type structure composed of polylauryl methacrylate. . Note that, in Example 14 below, it was confirmed that the polymer particles had the same structure.

Example 8 A polymer emulsion was obtained in the same manner as in Example 1, except that methacrylic acid was used in place of methacrylic acid and that the amount of acrylic acid was 1.0 times the amount of the monosaccharide unit of chitosan.

Example 9 After 50 g of stearyl methacrylate and 0.5 g of lauroyl peroxide were dissolved in a 1-liter beaker, 50 g of an aqueous chitosan / methacrylic acid solution prepared in the same manner as in Example 1 and 500 g of ion-exchanged water were mixed and stirred. The mixture was treated with an ultrasonic homogenizer for 30 minutes to prepare an emulsion of the monomer. The emulsion of this monomer was heated to 75 ° C. in the same reactor as in Example 1. After polymerization for 2 hours with stirring, a solution prepared by dissolving 0.1 g of ammonium persulfate in 10 g of water was added, and the reaction was further continued for 2 hours to obtain a polymer emulsion.

Example 10 In Example 3, polymerization was carried out at 75 ° C. for 2 hours, and a solution prepared by dissolving 0.1 g of potassium persulfate in 10 g of ion-exchanged water was added.
After further polymerization for 2 hours, the mixture was cooled to room temperature, neutralized with 0.1N aqueous sodium hydroxide solution, and adjusted to pH 8.5 to obtain a polymer emulsion.

Example 11 The procedure of Example 1 was repeated, except that 1.0 g of methacrylic acid was replaced by 2.0 g of methacrylic acid (2.0-fold molar amount with respect to the chitosan unit) and 1.0 g of N, N-dimethylacrylamide. A polymer emulsion was obtained in the same manner as described above.

Example 12 Polystyrene latex (average particle size: 1.51 μm, solid content: 20%) obtained by soap-free polymerization in a 1-liter glass reactor equipped with a stirrer, a cooler, and a nitrogen inlet tube.
g was heated to 40 ° C. Next, in a 1 liter beaker, 50 g of n-butyl methacrylate, 5 g of Emulgen 420,
Add 0.5 g of lauroyl peroxide and 200 g of ion-exchanged water,
Treated with ultrasonic homogenizer for 30 minutes, average particle size 0.58μm
An emulsion was obtained. This emulsion was mixed with the above polystyrene latex and stirred at 40 ° C. for 90 minutes. Thereafter, an aqueous solution of chitosan / methacrylic acid prepared in the same manner as in Example 1 was added, and the mixture was heated to an internal temperature of 75 ° C. After polymerization for 2 hours with stirring, a solution prepared by dissolving 0.1 g of ammonium persulfate in 10 g of water was added, and the reaction was further continued for 2 hours to obtain a polymer emulsion.

In the same manner as in Example 1, the polymer particles were spherical, the shell part was a layer derived from hydrophilic chitosan, and the core part was composed of a mixture of poly (n-butyl methacrylate) and polystyrene. It was confirmed that it had a core-shell structure.

Example 13 A polymer emulsion was obtained in the same manner as in Example 12, except that 50 g of t-butyl methacrylate and 5 g of diisobutyl adipate were used instead of 50 g of n-butyl methacrylate. In the same manner as in Example 1, the polymer particles were spherical, the shell portion was a layer derived from hydrophilic chitosan, and the core portion was a core-shell type having a mixture of poly (t-butyl methacrylate) and polystyrene. The structure was confirmed.

Example 14 In Example 1, instead of 50 g of stearyl methacrylate
Using 10 g of lauryl methacrylate and chitosan 2.5
A polymer emulsion was obtained in the same manner as in Example 1, except that 20 g of chitosan was used instead of g, and 8 g of methacrylic acid (equimolar amount to the monosaccharide unit of chitosan) was used instead of 1.0 g of methacrylic acid.

Example 15 50 g of stearyl methacrylate was placed in a 1-liter beaker.
After limonene (10 g) and lauroyl peroxide (0.5 g) were added and dissolved, 50 g of an aqueous chitosan / methacrylic acid solution prepared in the same manner as in Example 1 and 500 g of ion-exchanged water were mixed, and the mixture was treated with an ultrasonic homogenizer for 30 minutes while stirring to obtain monomers. An emulsion was prepared. The emulsion of this monomer was heated to 75 ° C. in the same reactor as in Example 1. After polymerization for 2 hours with stirring, a solution prepared by dissolving 0.1 g of ammonium persulfate in 10 g of water was added, and the reaction was further continued for 2 hours to obtain a polymer emulsion.

Example 16 A polymer emulsion was obtained in the same manner as in Example 15 except that 10 g of 1-menthol was used instead of limonene.

Example 17 In a 100 ml beaker, 10 g of limonene, 420 g of Emulgen 420,
1 g of ethanol and 100 g of water were added, and the mixture was treated with an ultrasonic homogenizer for 10 minutes with stirring to obtain a fragrance dispersion. 100 g of the polymer emulsion obtained in Example 1 was added to the fragrance dispersion, and the mixture was heated to 40 ° C. and reacted for 4 hours to obtain a polymer emulsion.

Comparative Example 1 45 g of commercially available chitosan (SK-10, manufactured by Koyo Chemical Co., Ltd., deacetylation degree: 85 to 88%, weight average molecular weight: 130,000) was added to 2.5 g.
g of water was added, and 1.0 g of methacrylic acid (equimolar amount based on the monosaccharide unit of chitosan) was added thereto, and the mixture was dissolved with stirring at 60 ° C. to prepare a chitosan / methacrylic acid aqueous solution. Next, n-butyl methacrylate 50 was placed in a 1-liter glass reactor equipped with a stirrer, a condenser and a nitrogen inlet tube.
g, emulgen 420 1 g, potassium persulfate 0.5 g, ion-exchanged water 200 g, and after purging with nitrogen, the mixture was heated with stirring to an internal temperature of 80 ° C., and reacted for 1 hour with stirring. The prepared chitosan / methacrylic acid aqueous solution was added, and polymerization was further performed for 3 hours to obtain a polymer emulsion.

Comparative Example 2 A reaction vessel equipped with a stirrer, reflux condenser, thermometer and nitrogen inlet tube was charged with 100 g of ion-exchanged water and commercially available chitosan (SK-10, manufactured by Koyo Chemical Co., Ltd., degree of deacetylation of 85). ~ 88%, weight average molecular weight 130,000) 30g, acrylic acid 15g, ion exchange water
400 g was added, the internal temperature was raised to 70 ° C. while performing nitrogen gas replacement with stirring, a solution of 1 g of potassium persulfate dissolved in 10 g of water was added, and 50 g of n-butyl acrylate was added to 30 g.
Dropped in minutes. After completion of the dropwise addition, the internal temperature was maintained for 1 hour, then a solution prepared by dissolving 1 g of sodium bisulfite in 20 g of water was added, the internal temperature was raised to 80 ° C, and the reaction was carried out for 2 hours to obtain a polymer emulsion.

Test Example 1 The chitosan-containing emulsions obtained in Examples 1 to 17 and Comparative Examples 1 and 2 were evaluated for the average particle size and the aqueous dispersion stability by the following methods. Table 1 shows the results.

<Evaluation method> Average particle diameter Measured by a light scattering method (particle size distribution analyzer LA-910; HORI
BA (manufactured by BA Corp.) ・ Water dispersion stability Chitosan-containing emulsion (solid content: 10% by weight) at 40 ° C
Then, the state (particle sedimentation, creaming, etc.) when left for one month was visually observed.

[0065]

[Table 1]

Test Example 2 (Maintenance of fragrance) The emulsion obtained in Examples 15 and 17 in which fragrance was included in a glass petri dish having a diameter of 5 cm so that the amount of fragrance was equal or limonene as a comparative example was applied, and 15 cm × 15 cm × 30cm
And the sensory evaluation of the intensity of the scent after a certain period of time was performed according to the following criteria. Table 2 shows the results. The evaluation points are shown by rounding off the decimal point below the average value of 10 panelists. 5: Strong, 4: Slightly strong, 3: Normal, 2: Slightly weak, 1: Weak, 0:
Do not feel the scent

[0067]

[Table 2]

Test Example 3 (Maintenance of Cool Feeling) 5 cm × 5% of the emulsion obtained in Example 16 containing 1-menthol such that the amount of 1-menthol was equal or the ethanol solution of 1-menthol was applied as a comparative example.
A cotton cloth of 5 cm was stuck on the upper arm, and after a certain period of time, the effect (cool feeling) of 1-menthol was sensory evaluated according to the following criteria.
Table 3 shows the results. The evaluation points are shown by rounding off the decimal point below the average value of 10 panelists. 5: Strong, 4: Slightly strong, 3: Feel, 2: Slightly weak, 1: Weak,
0: I don't feel

[0069]

[Table 3]

Continuation of the front page (56) References JP-A-9-3106 (JP, A) JP-A-7-242772 (JP, A) JP-A-9-2933 (JP, A) JP-A-3-134038 (JP) , A) JP-A-10-299215 (JP, A) WO 99/62974 (WO, A1) (58) Fields investigated (Int. Cl. ⁷ , DB name) C08L 5/00-5/16 C08F 291 / 00-291/18 C08L 51/00-51/10

Claims (10)

(57) [Claims] 1. An article having a core part and a shell part, wherein the average particle size is
A polymer emulsion containing polymer particles having a particle size of 30 μm or less, wherein a shell part is composed of chitosan (a) and a polymer (b) of an organic acid or a salt thereof having a reactive vinyl group, and a core part is a hydrophobic monomer. A polymer emulsion comprising the polymer (c) as a constituent component. 2. It has a core part and a shell part, and has an average particle size.
A polymer emulsion containing polymer particles having a particle size of 30 μm or less, wherein a shell part is composed of chitosan (a) and a polymer (b) of an organic acid or a salt thereof having a reactive vinyl group, and a core part is a hydrophobic monomer. A polymer emulsion comprising, as a constituent, a mixture of the polymer (c) and a non-polymerizable hydrophobic substance (d). 3. The polymer particles have an average particle size of 0.01 to 30 μm.
3. The polymer emulsion according to claim 1, wherein 4. An emulsion obtained by emulsifying and dispersing chitosan (a), an organic acid having a reactive vinyl group or a salt thereof (e), a hydrophobic monomer (f), and an oil-soluble polymerization initiator (g) in water. 2. The method according to claim 1, wherein a monomer droplet having an average particle diameter of 10 [mu] m or less is polymerized to form a core portion and a shell portion of the polymer particle. 5. Chitosan (a), an organic acid having a reactive vinyl group or a salt thereof (e), a hydrophobic monomer (f), a non-polymerizable hydrophobic substance (d), and an oil-soluble polymerization initiator (g) 3. The polymer emulsion according to claim 2, wherein monomer droplets having an average particle size of 10 μm or less obtained by emulsifying and dispersing in water are polymerized to form a core portion and a shell portion of the polymer particles. Manufacturing method. 6. The polymerization of the shell portion of the monomer droplet by introducing a water-soluble polymerization initiator (h) during or after the polymerization of the core portion in the monomer droplet. A method for producing a polymer emulsion. 7. A polymer particle (i) having an average particle size of 10 μm or less, which is compatible with the hydrophobic monomer (f), is added to the hydrophobic monomer.
(f) and swelling, and further, an aqueous solution of chitosan (a) and an organic acid having a reactive vinyl group or a salt thereof (e) is added, and the obtained swollen polymer particles are subjected to an oil-soluble polymerization initiator (g). The method for producing a polymer emulsion according to claim 1, wherein the polymerization of the core part and the shell part is carried out in the presence of. 8. A non-polymerizable hydrophobic substance (d) and a hydrophobic monomer (f) are added to polymer particles (i) having an average particle size of 10 μm or less, which are compatible with the hydrophobic monomer (f), and swelled. Further, an aqueous solution of chitosan (a) and an organic acid having a reactive vinyl group or a salt thereof (e) is added, and the obtained swollen polymer particles are treated with a core in the presence of an oil-soluble polymerization initiator (g). The method for producing a polymer emulsion according to claim 2, wherein the polymerization of the shell portion is performed. 9. A polymer particle (i) having an average particle size of 10 μm or less, which is compatible with the hydrophobic monomer (f), is added to the hydrophobic monomer.
(f) and swelling, and further, an aqueous solution of chitosan (a) and an organic acid having a reactive vinyl group or a salt thereof (e) is added, and the obtained swollen polymer particles are subjected to an oil-soluble polymerization initiator (g). The method for producing a polymer emulsion according to claim 1, wherein the polymerization of the core part and the shell part is carried out in the presence of a water-soluble polymerization initiator (h). 10. A non-polymerizable hydrophobic substance (d) and a hydrophobic monomer (f) are added to polymer particles (i) having an average particle size of 10 μm or less, which are compatible with the hydrophobic monomer (f), and swelled. Further, an aqueous solution of chitosan (a) and an organic acid having a reactive vinyl group or a salt thereof (e) is added, and the resulting swollen polymer particles are subjected to an oil-soluble polymerization initiator (g) and a water-soluble polymerization initiator.
The method for producing a polymer emulsion according to claim 2, wherein the polymerization of the core portion and the shell portion is carried out in the presence of (h).