JPH07163864A - Functional microcapsule and production thereof - Google Patents

Abstract

PURPOSE:To obtain a functional microcapsule sufficient in the coating properties of a core substance and excellent in mechanical strength and preservability by incorporating a polymerizable functional group into a polymer constituting a shell substance through a urethane bond. CONSTITUTION:In a functional microcapsule, a shell substance is constituted of a polymer into which a polymerizable functional group is incorporated through a urea or urethane bond formed by the reaction of a reaction product of a compd. represented by formula I and/or formula II with a polyamine or a hydroxy compd. with a first shell forming monomer having two or more isocyanate groups. In the formulae I, II, X is a halogen atom or a hydroxyl group, Y is a carbonyl group or a methylene group, R<1> and R<2> are a hydrogen atom or a methyl group and n is an integer of 1-6. This functional capsule is strong in bonding, sufficient in the coating properties of a core material and excellent in mechanical strength and preservability.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a microcapsule and a method for producing the same. Specifically, the present invention relates to a functional microcapsule having a polymerizable functional group in the capsule shell, which can easily modify the capsule shell by performing an addition reaction or a polymerization reaction with an arbitrary monomer, and a method for producing the same.

[0002]

2. Description of the Related Art Various proposals have heretofore been made for microcapsules consisting of a core substance and a capsule shell covering the core substance. The conventional microcapsule is used in such a manner that the capsule is destroyed by an external pressure. The core substance is released, or the permeability of the capsule shell is used to release the core substance to the outside without destroying the capsule. That is, the function of the capsule shell was required only to have mechanical strength for protecting the core substance or permeability for releasing the core substance. However,
In addition to mechanical strength or permeability to microcapsules,
When another function is required, for example, when the microcapsule is applied to an electrophotographic toner, the capsule shell must be provided with a chargeability function in order to visualize the electrostatic latent image. For the above purpose, JP-A-57-202547 and JP-A-63-2785.
No. 3, JP-A-63-27854 describe a method of obtaining a toner by spray-drying a polymer containing a charge control agent on the toner or coating the polymer by heating or pressure. However, the spray drying method has a drawback that the coating layer wraps a plurality of toner bases, resulting in a large toner particle size.
Even if the sieving operation is performed thereafter, there is a drawback that the yield of toner having a predetermined particle size is low. Further, since a large amount of organic solvent is used, there are safety and health problems. On the other hand, the method of coating the toner base material by heat fusion also has a drawback in that the toner particles are caused to adhere and aggregate to increase the toner particle size. Also, the method of fusing the coating polymer on the toner base with pressure is not a problem when the toner base particles to be heat-fixed are hard, but when this method is applied to the liquid core capsule toner, the capsule is destroyed. There is a drawback that is done.

Further, JP-A-62-227161 and JP-A-62-227162 describe a method of attaching a polymer of a monomer having a charging function to a toner base. Specifically, a compound having two polymerizable double bonds such as ethylene glycol dimethacrylate is used to form a polymerizable double bond on the capsule surface by a graft polymerization method, and then a polymerizable double bond having a charge control group is formed. A method for polymerizing monomers is described. This method has the advantages that the charge control group is localized on the toner surface, the fixing property of the toner binder is not impaired, and the coloring material is less susceptible to the charge property. However, a polymerizable double bond such as ethylene glycol dimethacrylate is not
The compound having an individual compound is generally poorly water-soluble, and when graft-polymerized in water using a catalyst such as cerium ion, the efficiency of forming a polymerizable double bond on the capsule surface is poor. Therefore, there are disadvantages that it requires a lot of catalyst and a lot of time, and that cleaning after the reaction also takes time, resulting in high cost.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object thereof is a microcapsule having a polymerizable functional group useful as an intermediate of a microcapsule toner. Therefore, it is to provide a functional microcapsule having a sufficient coverage with a core substance and excellent mechanical strength and storability. Another object of the present invention is that it is possible to reduce the fluctuation range of the capsule particle size, there are few safety and health problems, no special manufacturing equipment is required, and it is also suitable for manufacturing liquid core microcapsules. Another object of the present invention is to provide a method for producing microcapsules having a polymerizable functional group with high yield.

[0005]

Means for Solving the Problems As a result of intensive investigations by the present inventors to obtain functional microcapsules, the present inventors have found that a polymer having a urea bond or a urethane bond constituting a capsule shell substance has a polymerizable functional group. By introducing
Furthermore, they have found that the above object can be achieved by forming the capsule shell material by an interfacial polymerization method, and completed the present invention. That is, the first feature of the present invention is a functional microcapsule composed of a core substance and a shell substance, in which a polymerizable functional group is incorporated into a polymer constituting the shell substance via a urea bond or a urethane bond. .

The second feature of the present invention is the following general formula (I)
And / or a urea bond formed by the reaction product of the compound represented by the general formula (II) with a polyamine or a polyhydroxy compound reacting with a first shell-forming monomer having two or more isocyanate groups. Alternatively, the above-mentioned functional microcapsule has a shell substance composed of a polymer having a polymerizable functional group incorporated via a urethane bond.

[Chemical 2] (In the formula, X represents a halogen atom or a hydroxyl group, Y represents a carbonyl group or a methylene group, and R ¹ and R
² represents a hydrogen atom or a methyl group. n means an integer of 1 to 6. )

A third feature of the present invention is that at the time of producing a microcapsule consisting of a core substance and a shell substance, at least an oily droplet of a first shell-forming monomer having two or more isocyanate groups in the molecule. A mixture of a compound having at least one group selected from an amino group and a hydroxyl group and at least one polymerizable functional group in the molecule, which is present in the molecule, or another second shell-forming monomer is used as an aqueous medium. The method is for producing a functional microcapsule in which a capsule shell is formed by reacting it with the above-mentioned first shell-forming monomer at the interface of an oily droplet.

Next, the present invention will be described in detail. In the functional microcapsule of the present invention, the core substance may be selected from appropriate components according to the application and usage form of the microcapsule and is not particularly limited. Hereinafter, a case where the microcapsules are used as toner will be described as an example. As the core substance of the microcapsule toner, a core substance mainly composed of a component having a pressure fixing property is used for the purpose of pressure fixing, and a main component mainly having a heat fixing property is used for the purpose of heat fixing. A core material is used. Particularly for the purpose of pressure fixing, it is preferable that the core substance is mainly composed of a binder resin and a high-boiling-point solvent that dissolves the binder resin and a colorant, or that is mainly composed of a soft solid substance and a colorant. If necessary, instead of the colorant, magnetic powder or an additive such as silicone oil may be added for the purpose of improving fixability. Further, a high boiling point solvent which does not dissolve the binder resin can be added together with a high boiling point solvent which dissolves the binder resin. It is desirable to change the types and composition ratios of the constituent components depending on the purpose of pressure fixing and heat fixing.

As the binder resin, a known fixing resin can be used. Specifically, acrylic acid ester polymers such as polymethyl acrylate, polyethyl acrylate, butyl polyacrylate, 2-ethylhexyl polyacrylate, lauryl polyacrylate, and stearyl polyacrylate, polymethyl methacrylate, polymethyl methacrylate. Butyl methacrylate, poly (hexyl methacrylate), 2-ethylhexyl polymethacrylate, poly (lauryl methacrylate),
Methacrylic acid ester polymers such as poly (stearyl methacrylate), vinyl acetate polymers such as polyvinyl acetate, vinyl polypropionate, polyvinyl butyrate, olefin polymers such as polyethylene and polypropylene, and copolymers thereof, styrene such as styrene. -Based polymers, copolymers of styrene-based monomers and acrylic acid esters or methacrylic acid esters, styrene-butadiene copolymers, styrene-isoprene copolymers, styrene-styrene copolymers such as maleic acid copolymers, Polyvinyl ether,
Polyvinyl ketone, polyester, polyamide, polyurethane, rubbers, epoxy resin, polyvinyl butyral, rosin, modified rosin, terpene resin, phenol resin and the like can be used alone or in combination of two or more.

As the high boiling point solvent for dissolving the binder resin, an oily solvent having a boiling point of 140 ° C. or higher, preferably 160 ° C. or higher can be used. For example, Modern
Plastics Encyclopedia (19
75-1976) "Plasticizers". Further, for example, JP-A-58-145964 and JP-A-63-1633.
No. 73 may be selected from the high boiling point solvents disclosed as the core substance of the pressure fixing capsule toner. Specifically, phthalic acid esters (eg, diethyl phthalate, dibutyl phthalate); aliphatic dicarboxylic acid esters (eg, diethyl malonate, dimethyl oxalate, dioctyl adipate); phosphoric acid esters (eg,
Tricresyl phosphate, trixylyl phosphate); citric acid esters (eg, O-acetyltriethyl citrate); benzoic acid esters (eg, butylbenzoate, hexylbenzoate); fatty acid esters (eg, hexadecylmyristate) Alkylnaphthalenes (eg, methylnaphthalene, dimethylnaphthalene, isopropylnaphthalene, diisopropylnaphthalene);
Alkyl diphenyl ethers (eg, o-, m-, p-
Methyldiphenyl ether); amides of higher fatty acids or aromatic sulfonic acids (eg, N, N-dimethyllauroamide, N-butylbenzenesulfonamide); trimellitic acid esters (eg, trioctyl trimellitate); diarylalkanes (Eg, diarylmethane such as dimethyldiphenylmethane, 1-tolyl-1-phenylethane, 1-xylyl-1-phenylethane, diarylethane such as 1-ethylphenyl-1-phenylethane); chlorinated paraffins, etc. Can be mentioned. When a polymer having a long-chain alkyl group such as lauryl methacrylate homopolymer or copolymer is used as the binder resin, an aliphatic saturated hydrocarbon or an organic solvent containing the same as the main component (for example, manufactured by Exxon Chemical Co., Ltd. (Isopar G, Isopar H, Isopar L, etc.) can also be used.

Examples of the colorant include inorganic pigments such as carbon black, red iron oxide, navy blue, and titanium oxide, azo pigments such as fast yellow, disazo yellow, pyrazolone red, chelate red, brilliant carmine, and para brown, copper phthalocyanine, metal-free phthalocyanine. And a condensed polycyclic pigment such as flavantron yellow, dibromoanthrone orange, perylene red, quinacridone red, and dioxazine violet. Further, a disperse dye or the like can also be used. Furthermore, when the capsule toner is used as a magnetic one-component toner, all or part of the black colorant can be replaced with magnetic powder. As the magnetic powder, simple metals such as cobalt, iron and nickel or alloys thereof, magnetite, ferrite and the like can be used. In addition, a silane coupling agent, a surface treatment with a coupling agent such as a titanate coupling agent or an oil-soluble surfactant, or an acrylic resin, a styrene resin,
It may be a magnetic powder whose surface is coated with an epoxy resin.
The soft solid substance may be of any type as long as it is flexible and fixable at room temperature, but the polymer has a glass transition temperature Tg in the range of −60 to 5 ° C. or a polymer thereof and others. Mixtures with the polymers of

In the present invention, the polymerizable functional group incorporated in the polymer constituting the shell substance is a radical generator such as azobisisobutyronitrile or azobiscyanovaleric acid,
It refers to a functional group that can be polymerized by the action of electromagnetic waves such as heat, visible light, ultraviolet rays, and γ rays, or the action of an ionic catalyst such as a Ziegler catalyst and a redox catalyst. Specifically, a functional group containing an ethylenic double bond such as a vinyl group, an isopropenyl group, an acryloyl group or a methacryloyl group is particularly preferable. Examples of the "compound having a polymerizable functional group" (polymerizable compound) include compounds represented by the following general formula (I) and general formula (II).

[Chemical 3] (In the formula, X, Y, R ¹ , R ² and n are as defined above.)

The functional microcapsules of the present invention are produced by a so-called interfacial polymerization method. The method for producing microcapsules by the interfacial polymerization method is described, for example, in Japanese Examined Patent Publication No. 38-19.
574, Japanese Patent Publication No. 42-446, Japanese Patent Publication No. 2-
31381, JP-A-58-66948, JP-A-59-148066, and JP-A-59-1625.
As disclosed in JP-A-62-62, the first capsule shell forming monomer present in the oily droplets and the second capsule shell forming monomer present in the aqueous medium are It is a method of reacting at the interface to form a capsule shell.

As a method for incorporating the polymerizable functional group into the capsule shell via a urea bond or a urethane bond,
The following methods can be mentioned. For example, before being incorporated into a capsule shell, a polymerizable compound is reacted with a polyamine or a polyhydroxy compound, and in one molecule, one or more, preferably two or more groups selected from an amino group and a hydroxyl group are combined with a polymerizable functional group. A compound having one or more groups is prepared in advance. Incidentally, when a polyamine or polyhydroxy compound is reacted with a compound represented by the general formula (I),
When the corresponding amide or ester compound is produced and the compound represented by the general formula (II) is reacted, the corresponding amino alcohol or hydroxy ether compound is produced. Next, the obtained "compound having an amino group or a hydroxyl group and a polymerizable functional group" (for convenience, referred to as an active hydrogen-containing polymerizable compound) or a mixture of the compound and another second shell-forming monomer Are present in an aqueous medium, the first shell-forming monomer and optionally the core substance component are present in the oil droplets, and these are reacted at the oil droplet interface to form a capsule shell. At the time of this encapsulation reaction, the above polymerizable compounds may be present alone or in admixture of two or more in the aqueous medium. In addition, the polymerizable compound and the first shell-forming monomer and the like may be present in the oily droplets without preliminarily producing the active hydrogen-containing polymerizable compound, and may also serve as the second shell-forming monomer. Certain polyamines or polyhydroxy compounds can be present in an aqueous medium and reacted directly at the oily droplet interface to form capsule shells, as described above. In any of the methods, in order to coat the core substance well with the shell substance, the active hydrogen-containing polymerizable compound formed beforehand or at the time of forming the capsule shell contains 2 or more nitrogen atoms or oxygen atoms bonded to the active hydrogen. It is preferable to have one or more. When only one of these atoms is present in the molecule, the first capsule shell-forming monomer uses a trifunctional or higher functional isocyanate compound and / or an acid halide, an epoxy compound, or a trifunctional or higher functional monomer. It is necessary to use polyamine together. Further, in forming the capsule shell, it is possible to make the polyamine or the polyhydroxy compound exist in an excessive amount over the stoichiometric amount with respect to the polymerizable compound, and also serve as the second shell-forming monomer to improve the retention of the capsule core material. Desirable in terms.

Specific examples of polyamines include polyamines such as ethylenediamine, trimethylenediamine, tetramethylenediamine, hexamethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, aminopropylethylenediamine and phenylenediamine; piperazine; Examples thereof include piperazine compounds such as 2-methylpiperazine, 2,5-dimethylpiperazine, and aminoethylpiperazine, and polyoxyalkyleneamines known as Jeffamine (manufactured by Mitsuishi Texaco Chemical Co., Ltd.). Specific examples of the polyhydroxy compound include polyols such as ethylene glycol, propylene glycol, 1,4-butanediol, trimethylolpropane, o-dihydroxymethylbenzene, polyether polyol, polyester polyol, catechol, resorcinol, hydroquinone, and 4 , 4'-dihydroxydiphenylmethane, 2,2
And polyhydric phenols such as bis (4-hydroxyphenyl) propane. Furthermore, amino alcohols such as ethanolamine, diethanolamine, hydroxyethylethylenediamine and 2-hydroxytetramethylenediamine can be used.

The first capsule shell-forming monomer contains an isocyanate compound as an essential component, an acid halide,
It is also possible to mix and use an epoxy compound or the like. Specific isocyanate compounds include metaphenylene diisocyanate, tolylene diisocyanate, xylylene diisocyanate, diphenylmethane diisocyanate, 3,3′-dimethyldiphenyl-4,4′-diisocyanate, 3,3′-dimethyldiphenylmethane-
Examples thereof include diisocyanates such as 4,4′-diisocyanate, naphthalene diisocyanate and hexamethylene diisocyanate, and polyisocyanates known as so-called buret type, adduct type and isocyanurate type. Examples of acid halides include polybasic acid halides such as adipoyl dichloride, phthaloyl dichloride, terephthaloyl dichloride, and 1,4-cyclohexanedicarbonyl chloride. As the epoxy compound, bisphenol A type,
Epoxy compounds known as bisphenol F type, resorcin type, tetraphenylmethane type, novolak type, polyalcohol type, polyglycol type, and glycerin triether type can be mentioned. These monomers can be used alone or in combination of two or more. In addition to the above polyamine, polyhydroxy compound or amino alcohol, water can be used as the second capsule shell forming monomer.

In the present invention, when the active hydrogen-containing polymerizable compound is reacted with the isocyanate compound which is the first capsule shell-forming monomer, the capsule shell formed forms a urea bond or a urethane bond. It is composed of a polymer in which an active hydrogen-containing polymerizable compound is directly bonded in a monomer unit. That is, when a compound having an amino group in the molecule by reacting with a polyamine is used as the polymerizable compound, the compound is incorporated into polyurea, and at the same time, the capsule shell is branched in a state where the polymerizable functional group is branched. It is formed. On the other hand, when a compound having a hydroxyl group in the molecule is used by reacting with a polyhydroxy compound, similarly, the compound is incorporated into polyurethane, and at the same time, a capsule shell is formed in a state where a polymerizable functional group is branched. To be done. However, when a polymerizable compound having only one nitrogen atom or oxygen atom bonded to active hydrogen is used, it is bonded to the end of the urea bond or urethane bond. When an acid halide is used as the first capsule shell-forming monomer, the capsule shell further contains a polymer having a polyamide bond or a polyester bond, and when an epoxy compound is used in combination, the capsule shell contains Include a polymer obtained by adding a polymerizable compound containing active hydrogen to an epoxy group and further forming a urea bond or a urethane bond. These shell-forming components are capable of forming random, block or graft copolymers by adjusting the addition order and amount of the first and second capsule shell-forming monomers and the polymerizable compound. You can When the microcapsules in which the shell material is made of a polymer containing these polyureas or polyurethanes are used for an electrophotographic toner, it is particularly preferable from the viewpoint of electric resistance.

In the production of a capsule toner, a method of incorporating a binder resin as one of the core substance components into the capsule is to prepare in advance a polymer state together with other core substance components, a low boiling point solvent and a capsule shell forming component. Alternatively, a method of expelling the low boiling point solvent out of the system during the interfacial polymerization or after the completion of encapsulation and enclosing it in the capsule shell together with other core substance components can be adopted. Alternatively, the binder resin may be prepared by charging in the state of a monomer, forming a capsule shell by interfacial polymerization, and then polymerizing the monomer. The colorant or magnetic powder charged as one component of the core substance may be present at the interface between the core and the capsule shell or in the capsule shell after the capsule is formed. Further, it is desirable to change the thickness of the capsule shell for the purpose of pressure fixing and the purpose of heat fixing.

When the microcapsule of the present invention is used as a toner, an external additive may be added in order to add or polymerize a charge controllable monomer or to impart fluidity or chargeability. . Examples of the external additive include long-chain fatty acids such as stearic acid, which are generally used conventionally, their esters, amides, metal salts, and fine powders of silica, alumina, titania, fluororesins and the like. The external additive may be added by drying the capsule toner and then adhering the external additive to the toner surface with a mixer such as a V blender or a Henschel mixer, or by adding it to water or an aqueous mixed solution such as water / alcohol. After dispersing the additive, it is added to the capsule toner in the form of slurry and dried to attach the external additive to the toner surface. The encapsulated toner may also be used as a one-component developer that does not use a carrier or a two-component developer that uses a carrier. When using a carrier, it is not particularly limited as long as it is a known carrier, iron powder-based carrier,
Ferrite type carriers, surface-coated ferrite carriers, magnetic powder dispersion type carriers and the like can be used.

[0020]

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples. Example 1 (Synthesis of active hydrogen-containing polymerizable compound) Dry toluene 1
40 g of Jeffamine T-403 (manufactured by Mitsuishi Texaco Chemical Co., Ltd.) was dissolved in 00 g and cooled to 5 ° C. or lower. A solution prepared by dissolving 10 g of methacrylic acid chloride in 100 g of dry toluene was gradually added dropwise to this solution. Then, the mixture was reacted at room temperature for 1 hour and then with a 5% caustic soda aqueous solution for 20 hours.
% Sodium chloride solution and dried over magnesium sulfate. Toluene was distilled off from the dried solution by vacuum distillation to obtain a polymerizable compound (1).

(Production of Capsule Particles) 60 g of lauryl methacrylate-styrene copolymer (Mw = 9 × 10 ⁴ ) was added to and dissolved in a mixed solution of 20 g of Isopar H (manufactured by Exxon Chemical Co.) and 40 g of methyl isopropyl ketone. Sols Perth 3000 (made by Zeneca) in solution
1.2 g and 60 g of magnetic powder (EPT1000: manufactured by Toda Kogyo Co., Ltd.) were added, and the mixture was dispersed by a sand mill.
To 100 g of this dispersion, 30 g of an isocyanate monomer (Takenate D110N: manufactured by Takeda Pharmaceutical Co., Ltd.) and 20 g of methyl isopropyl ketone were added and thoroughly mixed (this liquid is referred to as liquid A). On the other hand, 400 g of ion-exchanged water is mixed with hydroxypropyl methylcellulose (Metroses 60SH5
0: manufactured by Shin-Etsu Chemical Co., Ltd.) was dissolved and then cooled to 5 ° C. (this liquid B liquid). Then, the solution B was stirred with an emulsifying machine (auto homomixer: manufactured by Tokushu Kiki Co., Ltd.), and the solution A was gradually added to the solution for emulsification. Thus, the average particle size of the oil droplet particles in the emulsion is about 12 μm O /
A W emulsion was obtained. Next, the emulsifier was replaced with a stirrer equipped with a propeller-type stirring blade (Three One Motor: manufactured by Shinto Kagaku Co., Ltd.), and the emulsion was stirred at 400 rpm, and then 10 g of the polymerizable compound (1) was added thereto. Was dripped. After completion of the dropping, the encapsulation reaction was carried out at 40 ° C. for 3 hours while distilling off isopropyl ketone. After completion of the reaction, the reaction mixture was poured into 2 liters of ion-exchanged water, sufficiently stirred and allowed to stand. After the capsule particles settled, the supernatant was removed. This operation was repeated 7 times to wash the capsule particles. Thus, the microcapsules of the present invention in which the polymerizable methacryloyl group was incorporated into the capsule shell via the urea bond were obtained.

(Evaluation of Microcapsule Performance) The obtained capsule particles were prepared into a suspension having a solid content concentration of 40%, 125 g of this suspension (corresponding to 50 g of capsule particles) was added with 125 g of ion-exchanged water, and a stirrer was added. (Three-one motor)
Stirring at 200 rpm. To this, 1.0 g of methyl methacrylate and 0.5 g of azobiscyanovaleric acid were added, and the reaction was carried out at 60 ° C. for 24 hours. After the reaction,
It was poured into 1 liter of ion-exchanged water, sufficiently stirred and allowed to stand. After the capsule particles settled, the supernatant was removed.
This operation was repeated three more times to wash the capsule particles. Next, the obtained capsule suspension was opened in a stainless vat, dried in a dryer (made by Yamato Scientific Co., Ltd.) at 60 ° C. for 10 hours, and then sieved with a sieve having an opening of 80 μm.
When the sieved microcapsules were washed with acetone and the amount of the graft polymer was measured, 60% of the charged methyl methacrylate was graft-polymerized on the capsules.
Further, the oil component in the obtained microcapsules was measured by thermogravimetric analysis and found to be 11%. Further, after heat-treating the microcapsules at 100 ° C. for 10 hours, the oil component was similarly measured and found to be 10%. As described above, the microcapsules of the present invention had a polymerizable functional group and were excellent in the retention of the capsule core material.

Comparative Example 1 Microcapsules were obtained by the same procedure as in Example 1 except that diethylenetriamine was added instead of the polymerizable compound (1). Next, in the same manner as in Example 1, after the capsule particles were grafted with methyl methacrylate and azobiscyanovaleric acid and washed with acetone to measure the amount of the graft polymer, almost all of the charged methyl methacrylate was charged. It has been washed away by acetone. Further, the oil component in the obtained microcapsules was measured by thermogravimetric analysis and found to be 11%. Further, after heat-treating the microcapsules at 100 ° C. for 10 hours, the oil component was similarly measured and found to be 10%. As can be seen from these results, the capsules of Comparative Example 1 had good retention of the capsule core material, but could not introduce a polymerizable functional group effective as an intermediate for functional microcapsules by a usual method. .

Example 2 (Synthesis of polymerizable compound containing active hydrogen) Dry toluene 1
Dissolve 10 g of diethylenetriamine in 00 g, 5 ° C
Cooled to: A liquid prepared by dissolving 10 g of glycidyl methacrylate in 100 g of dry toluene was gradually added dropwise to this solution. Then, after reacting at room temperature for 1 hour, toluene was distilled off by vacuum distillation to obtain a polymerizable compound (2).

(Production of Capsule Particles) Isopar H30
g and 40 g of ethyl acetate, 60 g of polylauryl methacrylate (Mw = 5 × 10 ⁴ ) was added and dissolved, and a titanate coupling agent (TTS:
70 g of magnetic powder, the surface of which was hydrophobized by Ajinomoto Co., Inc., was added, and the mixture was dispersed for 2 hours by a sand mill. 20 g of isocyanate monomer (Sumijour L: Sumitomo Bayer Urethane Co., Ltd.) and 24 g of ethyl acetate were added to the resulting dispersion.
Was added and mixed well (this liquid is referred to as liquid A). on the other hand,
After dissolving 10 g of hydroxypropylmethylcellulose (Metroses 60SH50) in 200 g of ion-exchanged water, 0.2 g of diethylenetriamine was mixed in advance and the temperature was 5 ° C.
It was cooled to (this liquid is liquid B). Then, the solution B was stirred with an emulsifying machine (auto homomixer), and the solution A was gradually added to the solution for emulsification. In this way, an O / W emulsion in which the average particle size of the oil droplet particles in the emulsion was about 12 μm was obtained. Next, the emulsifier was changed to a stirrer (three-one motor), and the emulsion was stirred at 400 rpm. Subsequently, 5 g of the polymerizable compound (2) was added to 5 g of diethylenetriamine as the second capsule shell-forming monomer.
% Aqueous solution 100 g, mixed and added dropwise. After the completion of dropping, the encapsulation reaction was carried out at 60 ° C. for 3 hours while distilling off ethyl acetate. After completion of the reaction, the reaction mixture was poured into 2 liters of ion-exchanged water, sufficiently stirred and allowed to stand. After the capsule particles settled, the supernatant was removed. This operation was repeated 7 times to wash the capsule particles. Thus, the microcapsules of the present invention were obtained in which the polymerizable methacryloyl group was incorporated into the capsule shell via the urea bond and the urethane bond.

(Evaluation of Performance of Microcapsules) The obtained capsule particles were prepared into a suspension having a solid content concentration of 40%, 125 g of this suspension was added with 125 g of ion-exchanged water, and the suspension was rotated 200 times with a stirrer (three-one motor). / Min. To this, 2.0 g of methyl methacrylate, 1.0 g of methacrylic acid and 0.5 g of azobiscyanovaleric acid were added, and the reaction was carried out at 60 ° C. for 24 hours. After completion of the reaction, the mixture was poured into 1 liter of ion-exchanged water, sufficiently stirred and allowed to stand. After the capsule particles settled, the supernatant was removed. This operation was repeated three more times to wash the capsule particles. Next, the obtained capsule suspension was opened in a stainless vat, dried in a dryer (made by Yamato Scientific Co., Ltd.) at 60 ° C. for 10 hours, and then sieved with a sieve having an opening of 80 μm. The sieved microcapsules were repeatedly washed with acetone and water, and the amount of the graft polymer was measured. As a result, 60% of the charged methyl methacrylate and methacrylic acid were graft polymerized on the capsule. Furthermore, when the washed microcapsules were mixed with an iron powder carrier of 100 μm and the charging property was examined by the blow-off method, it was −12 μC / g. As described above, the microcapsule of the present invention having a polymerizable functional group is useful as a capsule toner capable of being charged by adding or polymerizing a charge controllable monomer.

Comparative Example 2 Example 2 was repeated except that the polymerizable compound (2) was not added.
The same treatment as described above was carried out to produce microcapsules, which were then subjected to graft polymerization. However, when the obtained microcapsules were washed with acetone and water in the same manner as in Example 2 and the amount of the graft polymer was measured, the charged methyl methacrylate and methacrylic acid were not graft-polymerized at all. When the washed capsules were mixed with a 100 μm iron powder carrier and the chargeability was examined by the blow-off method, it was +1 μC / g. As can be seen from these results, the capsules of Comparative Example 2 did not have a polymerizable functional group effective as an intermediate of the functional microcapsules, so that they could not be charged by a usual addition or polymerization reaction.

Example 3 (Synthesis of polymerizable compound containing active hydrogen) 15 g of trimethylolpropane was cooled to 5 ° C. or lower, and 10 g of methacrylic acid chloride was gradually added dropwise. Then, after reacting at room temperature for 3 hours, unreacted methacrylic acid chloride was distilled off under reduced pressure to obtain a polymerizable compound (3).

(Production of Capsule Particles) Isopar H30
g and 40 g of methyl ethyl ketone in a mixed solution of poly-2
-Ethylhexyl methacrylate (Mw = 3 x 10 ⁴ )
Magnetic powder 7 whose surface was hydrophobized with a titanate coupling agent (TTS) in this solution
0 g was added, and the mixture was dispersed by a sand mill for 2 hours.
Isocyanate monomer (Takenate D) was added to the resulting dispersion.
120N: Takeda Pharmaceutical Co., Ltd.) 20 g, epoxy compound monomer (Epototo YD-8125: Toto Kasei Co., Ltd.) 10 g
And 24 g of methyl ethyl ketone were added and mixed well (this liquid is referred to as liquid A). On the other hand, 200g of deionized water
Hydroxypropyl methylcellulose (Metroses 6
After dissolving 10 g of 0SH50), 0.2 g of diethylenetriamine was premixed and cooled to 5 ° C. (this liquid B liquid). Next, emulsifier (auto homomixer)
The solution B was agitated with, and the solution A was gradually added to the solution to emulsify the solution. In this way, an O / W emulsion in which the average particle size of the oil droplet particles in the emulsion was about 12 μm was obtained. Next, the emulsifier was changed to a stirrer (three-one motor), and the emulsion was stirred at 400 rpm. Subsequently, 10 g of the polymerizable compound (3) was added to 50 g of a 2% aqueous solution of diethylenetriamine as the second capsule shell-forming monomer.
It mixed and dripped. After the completion of the dropping, the encapsulation reaction was carried out at 60 ° C. for 3 hours while distilling off the methyl ethyl ketone.
After completion of the reaction, the reaction mixture was poured into 2 liters of ion-exchanged water, sufficiently stirred and allowed to stand. After the capsule particles settled, the supernatant was removed. This operation was repeated 7 times to wash the capsule particles. Thus, the microcapsules of the present invention were obtained in which the polymerizable methacryloyl group was incorporated into the capsule shell via the urethane bond and the urea bond.

(Evaluation of Microcapsule Performance) The obtained capsule particles were prepared into a suspension having a solid content concentration of 40%, 125 g of this suspension was added with 125 g of ion-exchanged water, and the suspension was rotated 200 times with a stirrer (three-one motor). / Min. To this, 1.0 g of methyl methacrylate, 2.0 g of trifluoroethyl methacrylate and 0.5 g of azobiscyanovaleric acid were added, and the reaction was carried out at 60 ° C. for 24 hours.
After completion of the reaction, the mixture was poured into 1 liter of ion-exchanged water, sufficiently stirred and allowed to stand. After the capsule particles settled, the supernatant was removed. This operation was repeated three more times to wash the capsule particles. Next, the obtained capsule suspension was opened in a stainless vat, dried in a dryer (made by Yamato Scientific Co., Ltd.) at 60 ° C. for 10 hours, and then sieved with a sieve having an opening of 80 μm. The sieved microcapsules were repeatedly washed with acetone and the amount of the graft polymer was measured. As a result, 50% of the charged methyl methacrylate and trifluoroethyl methacrylate were graft-polymerized on the capsules. Furthermore, when the washed microcapsules were mixed with a 100 μm iron powder carrier and the chargeability was examined by the blow-off method, it was −15 μC / g. As described above, the microcapsule of the present invention having a polymerizable functional group is useful as a capsule toner capable of being charged by adding or polymerizing a charge controllable monomer.

Comparative Example 3 Example 3 except that the polymerizable compound (3) was not added.
The same treatment as described above was carried out to produce microcapsules, which were then subjected to graft polymerization. However, when the obtained microcapsules were washed with acetone and the amount of the graft polymer was measured in the same manner as in Example 3, the charged methyl methacrylate and trifluoroethyl methacrylate were not graft-polymerized at all. Also, wash 1 capsule
It was +1 μC / g when the chargeability was examined by a blow-off method after mixing with an iron powder carrier of 00 μm. As can be seen from these results, the capsules of Comparative Example 3 did not have a polymerizable functional group effective as an intermediate of the functional microcapsules, and therefore could not be charged by a usual addition or polymerization reaction.

[0032]

INDUSTRIAL APPLICABILITY The functional microcapsule of the present invention has a strong bond because the polymerizable functional group is directly bonded to the polyurea or polyurethane, and moreover, the core material has sufficient coverage and mechanical strength. And has excellent storage stability. In particular, when it is applied to a capsule toner, a good chargeability can be easily obtained. Furthermore, since the capsule shell can be easily modified by adding an arbitrary monomer to the polymerizable functional group, various uses other than the electrophotographic toner can be expected. Further, according to the method for producing a functional microcapsule of the present invention, it is also suitable for producing a microcapsule having a liquid core, has less safety and health problems, and does not require a special production apparatus to form a capsule shell. At times, the polymerizable compound can be efficiently introduced into polyurea or polyurethane.

Claims (3)

[Claims] 1. A functional microcapsule comprising a core substance and a shell substance, wherein the polymerizable functional group is incorporated into the polymer constituting the shell substance via a urea bond or a urethane bond. Micro capsule. 2. A first shell-forming unit in which a reaction product of a compound represented by the following general formula (I) and / or general formula (II) and a polyamine or a polyhydroxy compound has two or more isocyanate groups. 2. The functional microcapsule according to claim 1, wherein the shell substance is composed of a polymer having a polymerizable functional group incorporated through a urea bond or a urethane bond formed by reacting with a monomer. . [Chemical 1] (In the formula, X represents a halogen atom or a hydroxyl group, Y represents a carbonyl group or a methylene group, and R ¹ and R
² represents a hydrogen atom or a methyl group. n means an integer of 1 to 6. ) 3. A method for producing a functional microcapsule comprising a core substance and a shell substance, wherein a first shell-forming monomer having two or more isocyanate groups in the molecule is present in at least an oily droplet, A mixture of a compound having at least one group selected from an amino group and a hydroxyl group and at least one polymerizable functional group in the molecule or another second shell-forming monomer is present in an aqueous medium, A method for producing a functional microcapsule, which comprises reacting this with the first shell-forming monomer at the interface of an oily droplet to form a capsule shell.