JP2006061802A - Isocyanate-containing microcapsule and its manufacturing method, and coating composition, adhesive composition, and plastic modifying agent containing isocyanate-containing microcapsule - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To produce an isocyanate-containing microcapsule which has excellent water resistance and dispersibility due to a small particle size, and enables a stable keeping for a long term, and its manufacturing method. <P>SOLUTION: An isocyanate-containing solution is prepared by mixing and solving dicyclohexylmethane-4,4'-diisocyanate, isoparaffin, and ethyl acetate as a solving process. Next, an aqueous polyvinylalcohol solution and sodium dodecylbenzenesulfonate are added to the isocyanate-containing solution, which is agitated by a homomixer to prepare an O/W emulsion as a dispersion process. Further, as a film forming process, an aqueous diethylenetriamine solution is added while the O/W emulsion is agitated, which is heated and agitated for six hours. Thus, a dispersion of the isocyanate-containing microcapsule wherein dicyclohexylmethane-4,4'-diisocyanate, and isoparaffin are included with an isocyanate polymerization film can be obtained. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an isocyanate-containing microcapsule in which an isocyanate compound is encapsulated in a film and a method for producing the same. This isocyanate-containing microcapsule can be suitably used for a coating composition, an adhesive composition, a plastic modifier, and the like.

  Isocyanate compounds have the property of reacting with organic compounds having active hydrogen, such as amino groups and hydroxyl groups. Using this property, they are widely used as components for paints, adhesives, plastic modifiers, etc. Yes. However, the isocyanate compound is chemically active and has a problem of lacking long-term stability, such as being gradually decomposed by moisture in the air. In order to solve this problem, various proposals have been conventionally made.

For example, Patent Document 1 describes an isocyanate-containing polyolefin powder obtained by melt-mixing an isocyanate compound and a polyolefin resin, and pulverizing after cooling. Since this powder can prevent water from entering the powder due to the hydrophobicity of polyolefin, the isocyanate compound can be stored for a long period of time.
JP-A-7-68158

Patent Document 2 describes a powder obtained by kneading a hydrophobic plastic powder and an isocyanate compound. Since this powder can also prevent water from entering the powder by the hydrophobic plastic powder, the isocyanate compound can be stored for a long period of time.
JP 7-75707 A

Furthermore, Patent Document 3 describes an isocyanate compound-containing powder obtained by impregnating a porous vinyl chloride resin powder with an isocyanate compound and then covering the surface with a fine vinyl chloride powder. Since this isocyanate compound-containing powder can also prevent water from entering the isocyanate compound-containing powder by the fine vinyl chloride powder coated on the surface, the isocyanate compound can be stored for a long period of time.
Japanese Patent Laid-Open No. 8-113624

However, when the isocyanate compound-containing powder of Patent Documents 1 and 2 is placed in water, the isocyanate compound present on the surface of the powder is in direct contact with water, which may cause gelation or aggregation due to a chemical reaction. is there. In addition, since the isocyanate compound-containing powder of Patent Document 3 is simply coated with a fine vinyl chloride powder, water may enter through the gap and react with the isocyanate compound to cause the same phenomenon. There is. For this reason, their water resistance and long-term storage were not sufficient.

  In order to solve these problems, an isocyanate-containing microcapsule has been developed in which an isocyanate compound is encapsulated into a microcapsule to prevent direct contact between the isocyanate compound and water.

For example, Patent Document 4 proposes an isocyanate-containing microcapsule in which the surface of a powder containing an isocyanate compound is coated with polyvinyl acetal using the cloud point phenomenon of polyvinyl acetal.
Japanese Patent Laid-Open No. 54-13985

However, since this microcapsule is produced by rapidly coagulating polyvinyl acetal using an inorganic substance or a salt thereof, the coating film constituting the microcapsule tends to be porous. In addition, polyvinyl acetal becomes an equilibrium reaction with an adduct of water in water and is not a chemically stable compound. For this reason, there was a problem of poor water resistance.

Patent Document 5 proposes an isocyanate-containing microcapsule in which the surface of a powder containing an isocyanate compound is coated with polyvinyl alcohol using the cloud point phenomenon of polyvinyl alcohol.
Japanese Patent Publication No. 63-6258

According to this method, an isocyanate-containing microcapsule having excellent water resistance can be obtained. However, the microcapsules obtained by this method have a size as large as about 100 μm, and there is a problem that dispersion is non-uniform when they are used as components of paints and adhesives.

Furthermore, in Patent Document 6, an isocyanate compound, a hydrophobic substance (described as “hydrophobic core substance” in Patent Document 6) and a surfactant are mixed, and water is added to emulsify. It has been proposed to polymerize an isocyanate compound on the droplet surface with a polyvalent amine to form microcapsules.
JP 52-156775 A

Since the microcapsules are obtained by microencapsulating fine particles emulsified with a surfactant, the particle size of the microcapsules can be reduced. For this reason, even when it is a constituent component of a paint or an adhesive, it can be uniformly dispersed. However, it has not been clarified what kind of hydrophobic substance is suitable for forming a microcapsule that has excellent water resistance and can be stored stably for a long period of time.
In addition, this microcapsule is intended to develop the characteristics of a hydrophobic core material (insecticide etc. in the examples), and is not intended to utilize an isocyanate compound added to form a microcapsule film. Absent. That is, it can be said that this conventional microcapsule contains substantially no isocyanate compound.

  This invention is made | formed in view of the said conventional condition, Comprising: It is set as the problem which should be solved to provide the isocyanate containing microcapsule which is excellent in water resistance and can be stored stably for a long period of time. Another object of the present invention is to provide a method for producing an isocyanate-containing microcapsule that has excellent water resistance, can be stably stored for a long period of time, has a small particle size, and has excellent dispersibility.

  The isocyanate-containing microcapsule of the present invention is an isocyanate-containing microcapsule in which an isocyanate compound is encapsulated in a film. The film is made of a thermoplastic resin, and the isocyanate compound is dissolved in a hydrophobic organic compound having no polar functional group. Or it is distributed.

In the isocyanate-containing microcapsule of the present invention, since the isocyanate compound is separated from the outside by a film, the isocyanate compound can be prevented from coming into direct contact with water. For this reason, it is excellent in water resistance and can be stored stably for a long time. In addition, since the film constituting the microcapsule is made of a thermoplastic resin, the film is melted by heating, and the isocyanate compound encapsulated in the film can be released to the outside. For this reason, the isocyanate compound can be released at any time as needed.
Furthermore, since the isocyanate compound encapsulated in the film is dissolved or dispersed in a hydrophobic organic compound having no polar functional group, water has penetrated into the inside of the microcapsule even through defects in the film. However, the hydrophobic organic compound having no polar functional group prevents contact between the isocyanate compound and water. That is, hydrophobic organic compounds having no polar functional groups, such as paraffins and silicone oils, are extremely excellent in water repellency, and therefore can extremely effectively prevent contact between the isocyanate compound and water. . The hydrophobic organic compound may be a single compound or a mixture of a plurality of different hydrophobic organic compounds.
Liquids such as oils such as paraffin are preferred. This is because those having a melting point need to be heated to the melting point or higher during the emulsification step, which increases the reaction rate of the isocyanate and may cause gelation during emulsification. When a solid material is added, it is preferably used in a state dissolved by a solvent.

As described above, the isocyanate-containing microcapsules of the present invention are extremely excellent due to the synergistic effect of the barrier effect due to the presence of the thermoplastic resin film and the water resistance effect due to the hydrophobic organic compound having no polar functional group. Shows water resistance and enables long-term stable storage. For this reason, even if the capsule has a small particle size and a thin film, the isocyanate compound contained in the capsule can be stably stored for a long period of time. Such a small particle size isocyanate-containing microcapsule is excellent in dispersibility, and therefore can be suitably used as an additive for paints, adhesives, plastic modifiers and the like.

As an isocyanate compound in the isocyanate-containing microcapsule of the present invention,
Any compound having two or more isocyanate groups or isothiocyanate groups in one molecule can be used. Examples of such isocyanate compounds include m-phenylene diisocyanate, p-phenylene diisocyanate, 2,6-tolylene diisocyanate, 2,4-tolylene diisocyanate, naphthalene-1,4-diisocyanate, diphenylmethane-4,4′-diisocyanate, 3 , 3'-dimethyldiphenylmethane-4,4'-diisocyanate, xylylene-1,3-diisocyanate, 4,4'-diphenylpropane diisocyanate, trimethylene diisocyanate, hexamethylene diisocyanate, propylene-1,2-diisocyanate, butylene-1 , 2-diisocyanate, ethylidine diisocyanate, cyclohexylene-1,2-diisocyanate, cyclohexylene-1,4-diisocyanate, dicyclohexyl Diisocyanates such as rumethane-4,4′-diisocyanate and isophorone diisocyanate, and diisothioisocyanates such as p-phenylene diisothiocyanate, xylylene-1,4-diisothiocyanate and ethylidine diisothiocyanate can be used. Further, triisocyanates such as trimers of 4,4 ′, 4 ″ -triphenylmethane triisocyanate, toluene-2,4,6-triisocyanate, hexamethylene diisocyanate, polymethylene polyphenyl isocyanate, 4,4′- Polyvalent isocyanates such as dimethyldiphenylmethane-2,2 ′, 5,5′-tetraisocyanate, and polyvalent isocyanates such as polyvalent amines, polyvalent carboxylic acids, polyvalent thiols, polyvalent hydroxy compounds, and epoxy compounds. A compound added to a compound having a hydrophilic group can also be used, or a mixture of a plurality of the above-mentioned isocyanate compounds can be used. Hexamethylene diisocyanate with a slow reaction rate with cyclohexane It is preferable to use an aliphatic isocyanate compound such as hexylene-1,2-diisocyanate or dicyclohexylmethane-4,4′-diisocyanate.

The film of the isocyanate-containing microcapsule of the present invention is not particularly limited as long as it is a thermoplastic resin, and examples thereof include a polyurethane urea resin, an amino resin, and an acrylic resin. Among these, a polyurethane urea resin is preferable because a film can be easily formed by a reaction between an isocyanate compound and a polyvalent amine, as will be described later.

In addition, as a hydrophobic compound having no polar functional group for dissolving or dispersing the isocyanate compound, oils such as paraffin, isoparaffin, olefin, aliphatic diene, benzene, naphthalene, anthracene, biphenyl, terphenyl, etc. Aromatic hydrocarbons and derivatives thereof, hydrides, natural or synthetic oils such as turpentine oil and naphthenic oil can be used. Silicone oils such as octamethyltrisiloxane, decamethyltetrasiloxane, polymethylsiloxane, polymethylphenylsiloxane, etc. can also be used. Furthermore, these hydrophobic organic compounds can also be mixed and used. Solids such as petroleum wax, polyolefin, aliphatic and alicyclic hydrocarbon resins specified in JIS K-2235 such as solid paraffin wax, microcrystalline wax, and petrolatum may be added. The boiling point of the hydrophobic organic compound is preferably 80 ° C. or higher. This is because when the boiling point of the hydrophobic organic compound is less than 80 ° C., the hydrophobic organic compound gradually volatilizes during the production of microcapsules and in the storage state, thereby reducing the water resistance effect.

In the isocyanate-containing microcapsule of the present invention, the content of the hydrophobic organic compound is preferably 10 to 300 parts by weight with respect to 100 parts by weight of the isocyanate compound. When the amount of the hydrophobic organic compound is less than 10 parts by mass, the effect of preventing contact between water and the isocyanate compound is reduced. In addition, when the hydrophobic organic compound exceeds 300 parts by mass, the concentration of isocyanate is too thin when used as a paint, adhesive or plastic modifier, and as a paint, adhesive or plastic modifier. It becomes difficult to obtain the effect. More preferably, the hydrophobic organic compound is 50 to 150 parts by weight with respect to 100 parts by weight of the isocyanate compound.

The average particle size of the isocyanate-containing microcapsules of the present invention is preferably 0.5 to 50 μm. When the average particle size of the isocyanate-containing microcapsule exceeds 50 μm, the dispersibility when mixed with an adhesive or a paint is deteriorated, or the stability as an emulsion is deteriorated. In addition, when the average particle system is less than 0.5 μm, the specific surface area increases, so the amount of isocyanate that comes into contact with water during the microencapsulation process also increases, and the residual amount of isocyanate groups in the capsule decreases. Arise.

The isocyanate-containing microcapsules of the present invention can be contained therein as a constituent component of a coating composition, an adhesive composition or a resin improver. In this case, the coating film can be strengthened, the adhesive strength can be increased, or the properties of the resin can be changed by a crosslinking reaction with an isocyanate compound.

The isocyanate-containing microcapsules of the present invention can be produced by the following method. That is, the method for producing an isocyanate-containing microcapsule of the present invention comprises a dissolving step in which an isocyanate compound is dissolved or dispersed in a hydrophobic organic compound having no polar functional group to obtain an isocyanate-containing liquid, and the isocyanate-containing liquid and water. In the presence of a surfactant to form an O / W emulsion, and a film forming step for forming a film by interfacial polymerization of an isocyanate compound in the state of the O / W emulsion. Features.

In the method for producing an isocyanate-containing microcapsule of the present invention, as an dissolving step, an isocyanate compound is first dissolved or dispersed in a hydrophobic organic compound having no polar functional group to obtain an isocyanate-containing liquid. At this time, the hydrophobic organic compound may be a single substance or a mixture. Then, as a dispersion step, an isocyanate-containing liquid and water are mixed in the presence of a surfactant to obtain an O / W emulsion in which fine droplets of the isocyanate-containing liquid are dispersed in water. Furthermore, as a film forming step, an isocyanate compound present on the surface of fine droplets of the isocyanate-containing liquid is subjected to interfacial polymerization in the state of an O / W emulsion to form a film. Through the above steps, an isocyanate-containing microcapsule having an extremely small particle size can be easily prepared. The isocyanate-containing microcapsules thus obtained are obtained in a state dispersed in water, but the isocyanate-containing microcapsules may be isolated by a method such as centrifugation or spray drying.

In the film forming step, a polyvalent amine compound can be added to the O / W emulsion. If it is like this, interfacial polymerization will advance rapidly by reaction with a polyvalent amine and an isocyanate compound, and a film | membrane can be formed in a short time. Here, any polyvalent amine can be used as long as it contains two or more NH groups or NH2 groups in the molecule and can be dissolved or dispersed in the aqueous phase. Specific examples of such polyvalent amines include aliphatic polyamines such as diethylenetriamine, triethylenetetramine, 1,3-propylenediamine and hexamethylenediamine, epoxy compound adducts of aliphatic polyamines, piperazine and the like. Examples thereof include alicyclic polyvalent amines and heterocyclic diamines such as 3,9-bis-aminopropyl-2,4,8,10-tetraoxaspiro- (5,5) undecane. It is also possible to add a plurality of these polyvalent amines. The amount of polyamine added is appropriately determined according to the type of isocyanate compound, its content, the desired microcapsule hardness, etc., but is usually 0.1 to 100 parts by weight per 100 parts by weight of the isocyanate compound. Is added, more preferably 1 to 50 parts by weight.

Moreover, as temperature in a film formation process, it is 30-90 degreeC, More preferably, it is 40-80 degreeC. As will be described later, when a volatile polar solvent is mixed with the isocyanate-containing liquid in the dissolving step, the polar solvent can be quickly removed by setting the temperature in the film forming step higher.

In the dissolving step, a volatile polar solvent may be mixed with the isocyanate-containing liquid as necessary. When it is difficult to mix or disperse the isocyanate compound and the hydrophobic organic compound, there is a possibility that the composition becomes non-uniform. Further, the contact between the isocyanate compound and the polyvalent amine compound or water is inhibited by the hydrophobic organic compound, so that only a very weak film can be formed or a long time is required to form the film. In such a case, if a volatile polar solvent is added to the isocyanate-containing liquid, mixing or dispersion of the isocyanate compound and the hydrophobic organic compound becomes easy, and these problems can be solved. In addition, since a polar organic solvent will have a bad influence on storage stability, if it remains after a microencapsulation process, what has a low boiling point and is easy to volatilize is preferable. Specific examples include ethyl acetate, methyl ethyl ketone, and methylene chloride. These polar solvents may be removed by volatilization by heating at normal pressure or under reduced pressure.

Example 1
100 parts by weight of dicyclohexylmethane-4,4′-diisocyanate (NCO content 32.2%) as an isocyanate compound and 100 parts by weight of isoparaffin (“Isopar M” manufactured by ExxonMobil Chemical) as a hydrophobic organic compound In addition, 40 parts by weight of ethyl acetate as a polar solvent is mixed and dissolved to obtain an isocyanate-containing liquid.
Dispersing step Next, 600 parts by weight of a 5% aqueous polyvinyl alcohol solution and 2.5 parts by weight of sodium dodecylbenzenesulfonate were added to the isocyanate-containing liquid, and the mixture was stirred for 3 minutes at a rotational speed of 6000 rpm with a homomixer, and O / W emulsion.
Film Formation Step Further, while stirring the O / W emulsion at room temperature, 140 parts by weight of 4% diethylenetriamine aqueous solution is added, heated to 60 ° C., and stirred for 6 hours. Thus, an isocyanate compound and diethylenetriamine are interfacially polymerized to form an isocyanate polymerized film, whereby an isocyanate-containing microcapsule dispersion in which dicyclohexylmethane-4,4′-diisocyanate and isoparaffin are encapsulated in the isocyanate polymerized film is obtained. It was. The microcapsules thus obtained had an average particle size of 5 μm and a volume ratio of 28%.

(Example 2)
100 parts by weight of norbornene diisocyanate (NCO content 40.8%) as an isocyanate compound and 60 parts by weight of an aliphatic hydrocarbon resin as a hydrophobic organic compound (manufactured by Nippon Zeon, Quinton B-170, softening point 70 ° C.) In addition, 40 parts by weight of isoparaffin (“Isopar M” manufactured by ExxonMobil Chemical) as a hydrophobic organic compound and 60 parts by weight of ethyl acetate as a polar solvent are mixed and dissolved while heating at 70 ° C. A containing liquid was prepared.
Dispersing step Next, the isocyanate-containing liquid was cooled to room temperature, 600 parts by weight of 5% polyvinyl alcohol aqueous solution and 2.5 parts by weight of sodium dodecylbenzenesulfonate were added, and the mixture was stirred with a homomixer at a rotational speed of 6000 rpm for 3 minutes. O / W emulsion.
Film formation step Further, while stirring this O / W emulsion at room temperature, 140 parts by weight of 2% diethylenetriamine aqueous solution was added, heated to 60 ° C., stirred for 6 hours, and subjected to interfacial polymerization. A dispersion of contained microcapsules was obtained. The microcapsules thus obtained had an average particle size of 7 μm and a volume ratio of 26%.

(Example 3)
100 parts by weight of Takenate D-178N (Mitsui Takeda Chemical Co., Ltd., NCO content 19.2%) as the isocyanate compound, 100 parts by weight of KF-54 (Shin-Etsu Chemical Co., Ltd.) as the silicone oil, and ethyl acetate as the polar solvent Was mixed with 40 parts by weight to prepare an isocyanate-containing liquid.
Thereafter, a capsule dispersion having a size of 5 μm and a volume ratio of 27% was obtained in the same manner as in Example 1.

(Comparative Example 1)
In Comparative Example 1, in the dissolving step, methyl laurate was added in the same proportion in place of the isoparaffin used as the hydrophobic organic compound in Example 1. Other manufacturing conditions are the same as those in the first embodiment, and a description thereof will be omitted. The isocyanate-containing microcapsules thus obtained had an average particle size of 5 μm.

(Comparative Example 2)
In Comparative Example 2, in the dissolving step, without using a hydrophobic organic compound, Desmodur W (manufactured by Sumika Bayer Urethane Co., Ltd.) as an isocyanate compound is 200 parts by weight, and ethyl acetate is used as a polar solvent at a ratio of 60 parts by weight. Mixed. Other manufacturing conditions are the same as those in the first embodiment, and a description thereof will be omitted. The average particle size of the isocyanate-containing microcapsules thus obtained was 5 μm.

<Isocyanate group stability evaluation test>
The isocyanate-containing microcapsule dispersions of Examples 1 and 2 and Comparative Examples 1 and 2 produced as described above were allowed to stand at 25 ° C. for a long time, and the change in the content of isocyanate groups in the microcapsules was measured. did. The isocyanate group content was measured by measuring the FT-IR of the non-volatile component remaining after drying the dispersion of the isocyanate-containing microcapsules, and the absorption peak due to the isocyanate stretching vibration and the absorption peak due to the methylene stretching vibration. And the peak intensity ratio. The results are shown in Table 1.

From Table 1, it can be seen that the isocyanate-containing microcapsules of Examples 1 and 2 can stably maintain isocyanate groups over a long period of time even in water. On the other hand, it can be seen that the isocyanate-containing microcapsules of Comparative Example 1 and Comparative Example 2 cannot maintain the isocyanate group stably and are poor in stability to water. From the above results, it can be seen that if an isocyanate compound and a hydrophobic organic compound having no polar functional group are allowed to coexist in the inside of the film, an isocyanate-containing microcapsule having excellent water stability is obtained.

<Coating composition evaluation test>
Furthermore, the isocyanate-containing microcapsule dispersions of Examples 1 and 2 and Comparative Examples 1 and 2 were added to an acrylic paint, and the performance as a paint composition was evaluated.

That is, 100 parts by weight of an isocyanate-containing microcapsule dispersion and an acrylic latex (styrene / methyl methacrylate / acrylic acid-n-butyl / 2-hydroxymethyl acrylate / methacrylic acid copolymer, hydroxyl value 100 mgKOH / g, A water-based thermosetting urethane resin composition was prepared by mixing 100 parts by weight of an acid value of 10 mg KOH / g, Tg 40 ° C., concentration 50%, particle size 0.08 μm). The same operation was performed using the isocyanate-containing microcapsule dispersion of Example 2 and Comparative Examples 1 and 2. Thus, the water-based thermosetting urethane resin compositions of Examples 1 and 2 and Comparative Examples 1 and 2 were prepared.

The aqueous thermosetting urethane resin composition thus obtained was applied to a thickness of 30 μm, allowed to stand at 80 ° C. for 1 minute, and then cured at 120 ° C. for 30 minutes to obtain a coating film. This coating film was immersed in water at 25 ° C. for 24 hours, and the water resistance of the coating film was visually evaluated. The results are shown in Table 2.

  As can be seen from Table 2, it can be seen that the adhesive compositions using the isocyanate-containing microcapsules of Examples 1 and 2 do not change even after 3 weeks and become a coating film having excellent water resistance. On the other hand, in Comparative Examples 1 and 2, it is already whitened after one week and peeled off in two weeks, indicating that the water resistance is extremely poor.

<Adhesive composition evaluation test>
Further, the dispersions of isocyanate-containing microcapsules of Examples 1 and 2 and Comparative Examples 1 and 2 were added to the adhesive, and the performance as an adhesive composition was evaluated.

That is, 40 parts by weight of the isocyanate-containing microcapsule dispersion obtained in Example 1 and 100 parts of an ethylene-vinyl acetate copolymer emulsion (concentration 50%, polyvinyl alcohol content 5%) were mixed. 30 parts of calcium carbonate was added and stirred to prepare an adhesive composition. The same operation was performed using the isocyanate-containing microcapsule dispersion of Example 2 and Comparative Examples 1 and 2. Thus, adhesive compositions of Examples 1 and 2 and Comparative Examples 1 and 2 were prepared.

Using the adhesive composition thus obtained, a plywood was manufactured by laminating three layers of a waran plate having a thickness of 1.5 mm. The production conditions were such that the coating amount of the adhesive composition was 30 g / 30 × 30 cm 2, deposited for 5 minutes, then pressed at room temperature for 5 hours with a cold press (12 kgf / cm 2), and further hot-pressed at 120 ° C. ( 12 kgf / cm 2), and further cured at 25 ° C. for 3 days to obtain plywood. The plywood thus obtained was measured for normal adhesive strength and material breakage rate according to JAS standards. The results are shown in Table 3.

  As can be seen from Table 3, in the adhesive compositions using the isocyanate-containing microcapsules of Examples 1 and 2, the normal adhesive force hardly decreases even if the capsule has passed 3 weeks after preparation. The material breakage rate was over 90%. On the other hand, the adhesive composition using the isocyanate-containing microcapsules of Comparative Examples 1 and 2 showed a marked decrease in normal-state adhesive strength and a markedly reduced material breakage rate according to the elapsed time after the capsule adjustment. From the above results, it can be seen that the isocyanate-containing microcapsules of Examples 1 and 2 have extremely excellent water resistance and can be stored stably over a long period of time.

INDUSTRIAL APPLICABILITY The present invention can be stably stored for a long time as a socyanate-containing microcapsule, has excellent dispersibility, and can be used for a coating composition, an adhesive composition and a plastic modifier.

Claims (11)

In an isocyanate-containing microcapsule in which an isocyanate compound is encapsulated in a film,
The isocyanate-containing microcapsule, wherein the film is made of a thermoplastic resin, and the isocyanate compound is dissolved or dispersed in a hydrophobic organic compound having no polar functional group.   2. The isocyanate-containing microcapsule according to claim 1, wherein the film is an isocyanate polymerization film formed by interfacial polymerization of an isocyanate compound.   3. The isocyanate-containing microcapsule according to claim 1, wherein the content of the hydrophobic organic compound is 10 to 300 parts by weight with respect to 100 parts by weight of the isocyanate compound.   4. The isocyanate-containing microcapsule according to claim 1, wherein the hydrophobic organic compound is a compound which does not have a polar functional group in its structure and consists only of hydrocarbons. The isocyanate-containing microcapsule according to any one of claims 1 to 3, wherein the hydrophobic organic compound is silicone oil. The isocyanate-containing microcapsule according to any one of claims 1 to 5, wherein an average particle diameter is 0.5 to 50 µm.   The coating composition containing the isocyanate containing microcapsule of any one of Claims 1 thru | or 6.   The adhesive composition containing the isocyanate containing microcapsule of any one of Claims 1 thru | or 6.   The plastic modifier containing the isocyanate containing microcapsule of any one of Claims 1 thru | or 6. A dissolving step in which an isocyanate compound is dissolved or dispersed in a hydrophobic organic compound having no polar functional group to obtain an isocyanate-containing liquid;
A dispersion step of mixing the isocyanate-containing liquid and water in the presence of a surfactant to form an O / W emulsion;
A film forming step of interfacially polymerizing an isocyanate compound in the state of the O / W emulsion to form a film;
A process for producing an isocyanate-containing microcapsule, comprising: The method for producing an isocyanate-containing microcapsule according to claim 10, wherein a polyvalent amine compound is added to the O / W emulsion in the film forming step.