JP6037607B2 - Organic crystals - Google Patents

Description

The present invention relates to an organic crystal. More specifically, the present invention relates to an organic crystal made of a crystal containing an organic substance and useful as a dielectric, a ferroelectric, an ultraviolet absorber, an infrared absorber, a magnetic body, a conductor, a light emitter and the like.

The organic crystal is normally formed by a low molecular weight organic compound and exhibits various functions by being present as a crystal in a coating film or a molded product. Various organic low-molecular compounds that form organic crystals are known in various technical fields such as dyes, conductive materials, and ferroelectrics. Such properties of the organic low molecular weight compound are manifested in the form of organic crystals, thereby exhibiting characteristics unique to organic crystals. For example, in a film formed by dispersing organic crystals in a polymer compound, various functions peculiar to organic crystals are exhibited in the film. At this time, the dispersion state of the organic crystal in the film, the crystal structure and shape of the organic crystal, the content in the film, and the like affect the functionality of the organic crystal.

As a technique using a conventional organic crystal, a high attenuation material in which an organic low-molecular dielectric material or a ferroelectric material is dispersed in a rubber material or an elastomer material having a polar side chain is disclosed ( For example, see Patent Document 1.) This high-attenuation material is used as a vibration damping material, a soundproofing material or the like that absorbs vibrations and noises applied to a soundproof wall of a vehicle. As an embodiment, a high attenuation material by chlorinated polyethylene and an organic low molecular weight dielectric substance can be cited, and this is intended to suppress deterioration of attenuation performance with time.

JP-A-10-312191 (pages 2 to 4)

In the conventional technology using organic crystals, it is considered that the dispersibility is maintained by the interaction between the polarity of the matrix polymer and the organic low molecular weight dielectric material. Thus, when forming a film by dispersing organic crystals in a matrix polymer, the dispersibility of the organic crystals in the film is maintained by the interaction between the matrix polymer and the organic crystals, and the functionality of the organic crystals is expressed. However, there is room for contrivance to further suppress the deterioration with time of the organic crystal in various applications.

For example, there are problems such as aggregation of organic crystals due to aging, shape loss, and performance deterioration due to bleeding out. The aggregation of the organic crystals is related to the dispersibility of the organic crystals in the matrix polymer, whereby the organic crystals are aggregated at the time of dispersion with the matrix polymer or over time, and a good dispersion state is not obtained. The deformation of the organic crystal is related to the change in the shape of the organic crystal itself. If the organic crystal has a certain particle shape, the particle shape is lost, which may affect the dispersibility in the film and the function of the organic crystal itself. Will have an impact. Bleed-out means that the organic crystals are deposited and aggregated from the film surface to the film surface over time, which reduces the content of organic crystals in the film and causes some adverse effects due to the organic crystals being deposited on the film surface. May give.

Such performance degradation due to organic crystal aggregation, shape loss, bleed-out, etc. is caused by the dispersibility of organic crystals and the characteristics as organic crystals affect the performance. For example, dielectrics, ferroelectrics, ultraviolet rays It is considered to occur in technical fields such as an absorber, an infrared absorber, a magnetic body, a conductor, and a light emitter. For example, when an organic crystal is used as a dye, a conductive material, or a ferroelectric, due to the deterioration of the organic crystal described above with time, the optical characteristics change for the dye, the conductivity decreases for the conductive material, and the ferroelectric If it exists, it will cause a piezoelectric performance fall.

The present invention has been made in view of the above-described situation, and prevents various characteristics of organic crystals over time by preventing deterioration and deterioration of performance over time due to aggregation, shape loss, bleedout, and the like of organic crystals. It is an object of the present invention to provide an organic crystal that can be fully used in various applications and can be suitably used in various applications.

The present inventors paid attention to the fact that crystals containing organic substances are used in various applications as organic crystals, and have studied various problems related to the suppression of change over time as described above. It was found that changes over time can be prevented. Thereby, when organic crystals are used in various applications, the problems of aggregation of organic crystals due to aging, shape loss, and performance deterioration due to bleed-out can be solved. Regarding the aggregation of organic crystals, the polymer coat can prevent the property of the organic crystals to aggregate. Regarding the shape loss, the shape of the crystal can be maintained by wrapping the crystal with the polymer coat. Regarding bleed-out, when organic crystals of organic low molecular weight compounds are dispersed in the matrix polymer, the matrix polymer and the polymer coat are compared with those dispersed by the interaction between the matrix polymer and the organic low molecular weight compound. It is considered that the dispersion by the interaction can keep the dispersibility better, and the organic low molecular weight compound is less likely to be deposited on the film surface from the film.
Such organic crystals are useful in technical fields such as dielectrics, ferroelectrics, ultraviolet absorbers, infrared absorbers, magnetic materials, conductors, and light emitters. In these areas, to suppress over time change or deterioration, it is possible to provide a product which exhibits stable performance in time.

That is, the present invention relates to an organic crystal composed of a crystal containing an organic substance, wherein the surface of the crystal is covered with a polymer.
The present invention is described in detail below.
A combination of two or more preferred embodiments of the present invention described below is also a preferred embodiment of the present invention.

The organic crystal of the present invention comprises a crystal containing an organic substance.
In the present specification, the “crystal containing an organic substance” (hereinafter, also simply referred to as a crystal) includes an organic substance essential and is in a crystal form, and is not coated with a polymer. Say. The organic crystal of the present invention is obtained by coating such a crystal with a polymer. The polymer is also referred to as a coating polymer. Each of the crystal and the coating polymer may be one kind or two or more kinds.
As the organic substance, various substances can be applied in various technical fields, but usually an organic low molecular weight compound is used. Moreover, as long as an organic substance is essential, the crystal may be in the form of a salt, may be an organic-inorganic composite, or may contain an inorganic component such as a metal element.

The coating polymer in the organic crystal of the present invention preferably covers substantially all of the surface of the crystal, but it covers only part of the surface of the crystal or part or all of the surface of the crystal. Or may enter the inside of the crystal body. Here, “substantially covering the entire surface of the crystal” means that 50% or more of the entire surface area of the crystal is covered. Moreover, it is preferable to cover 70% or more, and it is more preferable to cover 90% or more.
The coating polymer is preferably a polymer, but may be a polymer compound different from the organic low-molecular compound to be a crystal. That is, as long as the crystal body can be coated, it may be a polymer composed of one or more monomer units, or may be an organic compound having a large number of carbon atoms and a so-called hydrocarbon chain. . Such a covering polymer may be in a state of being attached to the crystal body by intermolecular force or the like, or in a state of being covalently bonded to an organic compound constituting the crystal body. In addition, it is preferable that the coating polymer is not separated from the crystal during preparation of a product using organic crystals or over time.
As described later, the coating polymer preferably has a high molecular weight, a high glass transition temperature, and a cross-linking condition.

As preferable embodiment of this invention, the dispersion containing the said organic crystal, the dispersion containing the said organic crystal and a polymer, etc. are mentioned. In addition, a coating film formed by forming a film containing the dispersion containing the organic crystals and a coating film formed by forming a dispersion containing the organic crystals and the polymer are also preferable embodiments of the present invention. .
Preferred embodiments of the dispersion containing the organic crystal and the coating film formed by forming the film include the following Embodiments 1 and 3, and the like, and the dispersion containing the organic crystal and the polymer and the same As a preferable form of the coating film formed by forming the film, the following embodiment 2 and the like are exemplified.

The dispersion according to the first embodiment is preferably an organic crystal as an essential component and the organic crystal dispersed in a dispersion medium (solvent). By applying this to a substrate or the like and drying, a coating film formed by forming a film of the dispersion can be obtained.
In the first embodiment, the crystal body is covered with a coating polymer and further covered with a matrix polymer, that is, the crystal body, the coating polymer, and the matrix polymer are stacked in this order (three-layer structure). It is preferable.
Here, the matrix polymer means a polymer that becomes a matrix when formed into a coating film.
As described above, the polymer that coats the crystal is referred to as the coating polymer. However, in the organic crystal having the three-layer structure, when the dispersion of the organic crystal is used as a coating film, the crystal Since the outermost layer polymer for coating is a matrix polymer, it is also referred to as a matrix polymer for convenience.
In such a form, it is possible to obtain a coating film in a form in which organic crystals obtained by coating a crystal body with a polymer are dispersed in a matrix polymer. A conceptual diagram of the first embodiment is shown in FIG.

The resin composition of the second embodiment is preferably one in which an organic crystal and a polymer are essential components and the organic crystal is dispersed in the polymer. By coating and drying this on a substrate or the like, a coating film formed by forming a film of the resin composition can be obtained.
In the second embodiment, it is possible to obtain a coating film in a form in which organic crystals obtained by coating a crystal body with a coating polymer are dispersed in a matrix polymer which is an essential component polymer contained in the dispersion together with the organic crystals. it can. A conceptual diagram of the second embodiment is shown in FIG.

The dispersion according to Embodiment 3 is preferably a mixture of an emulsion in which an organic crystal is an essential component and the organic crystal is dispersed in a dispersion medium (solvent) and an emulsion of a matrix polymer. By applying this to a substrate or the like and drying, a coating film formed by forming a film of the dispersion can be obtained.
In the third embodiment, it is possible to obtain a coating film in which the organic crystals formed by coating the crystal body with the coating polymer are dispersed in the matrix polymer present in the matrix polymer emulsion. A conceptual diagram of the third embodiment is shown in FIG.

In any of Embodiments 1 to 3, it is preferable that the coating polymer and the matrix polymer are incompatible. As a result, the organic crystals coated with the coating polymer incompatible with the matrix polymer are dispersed, not dissolved, in the matrix polymer. Therefore, it is possible to develop the characteristics that are manifested when the crystal is dispersed while preventing the characteristics from changing or deteriorating over time.
Each of the coating polymer and the matrix polymer may be one kind or two or more kinds.
In any of Embodiments 1 to 3, it is preferable that the coating polymer and the crystal are bonded. That is, it is preferable that a bond between the coating polymer / crystal body is formed.
Furthermore, in any of Embodiments 1 to 3, it is preferable that the coating polymer and the matrix polymer cover the crystal, as described above, substantially covering the entire crystal, Only a part may be covered.
Note that the organic crystal can have a structure of four or more layers in addition to the two-layer structure or the three-layer structure. When a dispersion of organic crystals having a structure of four or more layers is used as a coating film, the polymer layer (innermost layer) in contact with the crystal becomes a coating polymer, and the outermost polymer layer becomes a matrix polymer. The polymer layer sandwiched between the outermost layer and the outermost layer becomes a coating polymer or a matrix polymer depending on the type and properties of the polymer used. In this case, the coating polymer in the bonding between the coating polymer and the crystal body means the innermost layer coating polymer.

In the above-described embodiment, when a coating polymer / crystal body bond is formed, the organic low molecular weight compound constituting the crystal body has a reactive functional group (functional group A), and the bond is coated. The polymer also has a reactive functional group (functional group B) and can be formed by the reaction of functional group A and functional group B. What is necessary is just to use what is applied when the said organic group couple | bonds an organic compound and a polymer, and the said functional group may be 1 type, respectively, and may be 2 or more types.
The functional group A and the functional group B may be the same or different.

When a solvent is used in the embodiment, the solvent may be any solvent as long as it can disperse the dispersion or the resin composition, and may be appropriately selected in various applications. For example, water or a solvent mainly composed of an aqueous solvent can be used.
Moreover, what is necessary is just to select suitably as components other than an essential component according to the performance calculated | required in various uses.

In Embodiments 1 to 3 described above, the coating polymer can form a coating film while suppressing the aggregation of the organic crystals, deformation of the shape, and bleed-out, as compared with the case where the crystal is simply dispersed in the polymer. In addition, these problems can be suppressed over time. The above-described performance of the organic crystal of the present invention, the dispersion essential to the organic crystal, the resin composition, and the coating film formed by them can be evaluated by measuring the degree of crystallinity over time. If the degree of crystallinity decreases, it can be evaluated that organic crystals are aggregated, deformed, bleed out, and the like.

The organic crystal of the present invention is preferably used as at least one selected from the group consisting of a dielectric, a ferroelectric, an ultraviolet absorber, an infrared absorber, a magnetic material, a conductor and a light emitter. In these applications, it suppresses over time change or deterioration, the action effect of the present invention to provide a product which exhibits stable performance in time can be exhibited, thereby the utility of the product for each application Can be increased.

Of the various uses described above, when an organic crystal is used as a dielectric or a ferroelectric, a dispersion or a resin composition made of the organic crystal is a piezoelectric material. The material is preferably used as a vibration damping material or a sound absorbing material. That is, it can be suitably used as a piezoelectric damping material that absorbs and extinguishes vibration by converting vibration energy into electric energy.
A form using the organic crystal of the present invention as an organic crystal for a vibration damping material and a vibration damping material using the organic crystal for a vibration damping material are one of the preferred embodiments of the present invention.

Damping materials are used to prevent vibrations and noises in various structures and maintain quietness. For example, they are used under the interior floors of automobiles, as well as railway vehicles, ships, airplanes, and electrical equipment. It is also widely used in equipment, building structures, construction equipment, etc.
As a conventional damping material, an asphalt sheet containing inorganic powder has been used under the interior floor of an automobile, but since it is necessary to heat-seal, improvement in workability and the like is desired. In addition, coating-type damping materials (paints) have been developed. For example, various anti-vibration paints have been proposed that can obtain a vibration absorbing effect and a sound absorbing effect by a coating film formed by spraying on a corresponding portion by spraying or applying by an arbitrary method. Specifically, for example, as a water-based vibration-damping paint with improved coating film hardness obtained by blending a synthetic resin powder with a color developing agent such as asphalt, rubber, synthetic resin, and the like suitable for indoor use in automobiles, Anti-vibration coatings in which activated carbon is dispersed as a filler in a resin emulsion have been developed. However, even with these conventional products, the vibration damping performance is still not at a sufficiently satisfactory level, and there is a need for a technique that can further exhibit the vibration damping performance.
Under such circumstances, the technique of using the organic crystal of the present invention, the dispersion containing the organic crystal as an essential component, and the resin composition in the application of the vibration damping material is to improve the damping performance and suppress the deterioration of the damping performance with time. It is effective and greatly contributes to the improvement of the performance of the damping material.
In the following, preferred forms of crystals, organic crystals, dispersions, resin compositions, and coating films formed by them in organic crystals will be described in detail, but the preferred forms are particularly used for piezoelectric materials, that is, damping materials. It is suitably applied to.

The shape of the crystal is not particularly limited, and examples thereof include particles such as spheres, ellipsoids, and polygons; flakes such as scales and plates; needles, columns, rods, cylinders, and the like. Preferably, they are needle-like, columnar, rod-like and the like. These shapes may be present alone or in combination of two or more. Further, the shape of the organic crystal is preferably the same as the shape of the crystal. That is, it is preferable that the crystal is coated with a polymer so as not to change the shape and crystal structure of the crystal.

The average particle diameter of the crystal is preferably 0.1 to 100 μm. The average particle diameter of the crystal is variously set depending on the technical field to which the organic crystal is applied. Usually, if it is less than 0.1 μm, it tends to be aggregated and difficult to handle. Exceeding this may affect dispersibility. More preferably, the upper limit is 50 μm, the lower limit is 0.2 μm, and more preferably, the upper limit is 20 μm and the lower limit is 0.3 μm.
Moreover, as an average particle diameter of an organic crystal, it is preferable that it is 0.12-120 micrometers. More preferably, the upper limit is 60 μm, the lower limit is 0.14 μm, and more preferably, the upper limit is 24 μm and the lower limit is 0.16 μm.
In the case of particles having an aspect ratio larger than 1 as described later, as shown in FIG. 4, the particle diameter has a major axis and a minor axis, and the major axis is used as the average particle diameter described here.
The average particle diameter can be applied to a crystal body having any shape described above.

Here, when the particle group is composed of many particles having non-uniform diameters, the particle diameter representing the particle group is defined as the average particle diameter. As the particle diameter, the particle length measured according to a general rule is used. For example, in the case of a microscopic observation method, two or more lengths such as a major axis diameter, a minor axis diameter, and a constant direction diameter are measured for one particle, and the average value is defined as the particle diameter. It is preferred to make measurements on at least 50 particles.
The average particle diameter can be measured with a transmission electron microscope (TEM), a scanning electron microscope (SEM), an atomic force microscope (AFM), an optical microscope, a digital microscope, etc. In the present invention, The value measured by SEM is used.
Specifically, using a SEM (manufactured by Hitachi High-Tech, FE-SEM, S-4800), measuring the particle diameter of 50 particles by analyzing the measurement image, and calculating the average value thereof, the crystal The average particle size of the body and organic crystals is determined. In the case of particles having an aspect ratio greater than 1, the major axis of 50 particles is measured and the average value of these is calculated.

The aspect ratio (ratio of major axis to minor axis, that is, major axis / minor axis) of the crystal is preferably 2 or more from the viewpoint of dispersibility of organic crystals and expression of various performances. More preferably, it is 4 or more, more preferably 6 or more. The upper limit of the aspect ratio of the crystal is preferably 20 or less. More preferably, it is 18 or less, More preferably, it is 15 or less. The aspect ratio of the organic crystal is preferably the same as that of the crystal.
The aspect ratio can be obtained as an average value of major axis / average minor axis of each shape.
The aspect ratio can also be measured based on the above-described method for measuring the average particle diameter, but in the present invention, a value measured by SEM is used.
Specifically, using a SEM (manufactured by Hitachi High-Tech, FE-SEM, S-4800), the major axis and minor axis of 50 particles are measured by analyzing the measurement image, and each of the major axis and minor axis is measured. By calculating the average value, the aspect ratio (average value of major axis / average value of minor axis) of the crystal and the organic crystal is obtained.

In the organic crystal of the present invention, the mass ratio of the polymer and the crystal is preferably 1: 9 to 9: 1 from the viewpoint of the balance between the performance expressed by the organic crystal and the strength of the coating film. More preferably, it is 2: 8 to 8: 2, and still more preferably 3: 7 to 7: 3.

The material of the crystal constituting the organic crystal is not particularly limited as long as it contains an organic substance. For example, a phenol compound, an aromatic primary amine compound, an aromatic secondary amine compound, diphenylamine Compounds, sulfenamide compounds, thiourea compounds, thiuram compounds, thiazole compounds, guanidine compounds, aldehyde-ammonia compounds, aldehyde-amine compounds, dithiocarbamate compounds, xanthate compounds, carbonic acid Examples include esters (such as ethylene carbonate) and amide compounds (such as N-methylacetamide (NMAC)). These can be used alone or in combination of two or more. Of the crystalline materials, phenolic compounds, sulfenamide compounds, aromatic secondary amine compounds, and the like are preferable, and 4,4′-thiobis (2-methyl) is more preferable. -6-tert-butylphenol), N, N-dicyclohexylbenzothiazole-2-sulfenamide, α, α′-bis (4-hydroxyphenyl) -1,4-diisopropylbenzene, and the like.
The crystal can be produced by a known method. For example, N, N-dicyclohexylbenzothiazole-2-sulfenamide can be prepared by dissolving in acetone and then reprecipitating into water. A commercially available crystal may be used.

The organic crystal production method of the present invention is not particularly limited as long as the surface of the crystal body can be coated with a polymer. For example, in the presence of a crystal body dispersed in a dispersant in an aqueous medium. An organic crystal can be produced in the form of an aqueous dispersion by emulsion polymerization of a polymerizable monomer. Further, if the organic crystal is separated from the aqueous dispersion and dried, the organic crystal can be produced in the form of powder. Furthermore, by redispersing the organic crystals in the form of powder in a dispersion medium other than the aqueous medium, or by replacing the dispersion medium of the aqueous dispersion with a dispersion medium other than the aqueous medium, Can be produced in the form of a dispersion dispersed in a dispersion medium other than an aqueous medium.
Alternatively, an organic crystal can be produced in the form of an aqueous dispersion by suspension polymerization of a polymerizable monomer in a state where the crystal is mechanically dispersed without using a dispersant.

The polymerizable monomer used in the polymerization reaction is not particularly limited as long as it can form a polymer coating layer on the surface of the crystal, and whether or not the crystal has a functional group on the surface thereof, Although it depends on the type, for example, polymerizable monomers containing a vinyl group, a (meth) acryloyl group, an epoxy group, an amino group, a carboxyl group, a hydroxyl group and the like can be mentioned. The said polymerizable monomer may be used by 1 type, or may use 2 or more types together. In each of the following polymerizable monomers, one kind may be used, or two or more kinds may be used in combination.

Examples of the vinyl group-containing polymerizable monomer include vinyl halides such as vinyl chloride and vinylidene chloride; vinyl esters such as vinyl acetate; styrene derivatives such as styrene, α-methylstyrene, vinyl toluene, and chlorostyrene; Is mentioned. Styrene derivatives such as styrene are preferred.

Examples of the (meth) acryloyl group-containing polymerizable monomer include, for example, methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, and (meth) acrylic acid. Cyclohexyl, isobornyl (meth) acrylate, ethylene glycol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, diethylene glycol di (meth) acrylate, trimethylol Examples include (meth) acrylic acid esters such as propane tri (meth) acrylate and allyl (meth) acrylate. Preferred are methyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, diethylene glycol di (meth) acrylate and the like.

Examples of the epoxy group-containing polymerizable monomer include unsaturated carboxylic acid esters such as glycidyl (meth) acrylate; unsaturated glycidyl ethers such as vinyl glycidyl ether and allyl glycidyl ether; and the like. Unsaturated carboxylic acid esters such as glycidyl (meth) acrylate are preferred.

Examples of the amino group-containing polymerizable monomer include (meth) acrylic acid N atom-containing esters such as aminoethyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, and dimethylaminopropyl (meth) acrylate; Vinylamines such as N-vinyldiethylamine and N-acetylvinylamine; Allylamines such as allylamine, α-methylallylamine, N, N-dimethylallylamine; (meth) acrylamide, N-methyl (meth) acrylamide, N, N- (Meth) acrylamides such as dimethyl (meth) acrylamide; aminostyrenes such as p-aminostyrene; Preferred are (meth) acrylic acid N atom-containing esters such as aminoethyl (meth) acrylate and dimethylaminoethyl (meth) acrylate.

Examples of the carboxyl group-containing polymerizable monomer include unsaturated monocarboxylic acids such as (meth) acrylic acid and crotonic acid; unsaturated dicarboxylic acids such as maleic acid, itaconic acid and citraconic acid; Monoesterified products; anhydrides of these unsaturated dicarboxylic acids; and the like. Preferably, it is an unsaturated monocarboxylic acid such as (meth) acrylic acid.

Examples of the hydroxyl group-containing polymerizable monomer include (meth) acrylic acid 2-hydroxyethyl, (meth) acrylic acid 2-hydroxypropyl, α-hydroxymethyl methyl acrylate, α-hydroxymethyl ethyl acrylate (meth) ) Acrylic acid hydroxyl group-containing esters; polycaprolactone-modified (meth) acrylic acid esters; polyoxyethylene-modified or polyoxypropylene-modified (meth) acrylic acid esters; Preferred are (meth) acrylic acid hydroxyl group-containing esters such as (meth) acrylic acid 2-hydroxyethyl and (meth) acrylic acid 2-hydroxypropyl.

The amount of the polymerizable monomer used may be adjusted as appropriate according to the amount of crystal used, and is not particularly limited. For example, it is 5 to 200 parts by weight with respect to 100 parts by weight of the crystal. Is preferred. When the amount of the polymerizable monomer used is less than 5 parts by mass, the polymerization reaction is unlikely to proceed rapidly, and the crystal surface tends to be difficult to efficiently coat with the polymer. On the other hand, when the amount of the polymerizable monomer used exceeds 200 parts by mass, there is a tendency that many polymer particles not containing a crystal are easily generated. More preferably, they are 10 mass parts or more and 150 mass parts or less, More preferably, they are 15 mass parts or more and 100 mass parts or less.

Examples of the coating polymer in the present invention include a polymer obtained by polymerizing the polymerizable monomer. Preferably, methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isobornyl (meth) acrylate, diethylene glycol di (meth) acrylate, (meth) Examples thereof include polymers obtained by polymerizing at least one polymerizable monomer selected from acrylic acid, 2-hydroxyethyl (meth) acrylate, styrene, and vinyl acetate.

As said coating polymer, what has satisfy | fills conditions, such as having high molecular weight, having a high glass transition temperature, and bridge | crosslinking is more preferable.
The coating polymer preferably has a weight average molecular weight of 20,000 or more. If the molecular weight is less than the above, there is a possibility that deterioration of the crystal body over time may not be suppressed. The weight average molecular weight is more preferably 50,000 or more, and even more preferably 100,000 or more.
In the case of an uncrosslinked polymer, the weight average molecular weight (Mw) can be determined by GPC (gel permeation chromatography) measurement under the following measurement conditions.
Measuring instrument: HLC-8120GPC (trade name, manufactured by Tosoh Corporation)
Molecular weight column: TSK-GEL GMHXL-L and TSK-GELG5000HXL (both manufactured by Tosoh Corporation) are connected in series. Eluent: Tetrahydrofuran (THF)
Standard material for calibration curve: Polystyrene (manufactured by Tosoh Corporation)
Measurement method: The measurement object is dissolved in THF so that the solid content is about 0.2% by mass, and the molecular weight is measured using an object obtained by filtration through a filter as a measurement sample.

The coating polymer preferably has a glass transition temperature of 40 to 200 ° C. When a polymer having such a glass transition temperature is used as the coating polymer, the coating polymer is stable at room temperature or higher and is suitable for application to various applications. The glass transition temperature of the coating polymer is more preferably 50 to 190 ° C, still more preferably 60 to 180 ° C. In addition, it can adjust to the said glass transition temperature range by selection of the kind, ratio, etc. of a polymerizable monomer.
The glass transition temperature (Tg) may be determined based on the knowledge already obtained, and may be controlled by the type and use ratio of the monomer component described later. It can be calculated from the following formula (1).

In the formula, Tg ′ is Tg (absolute temperature) of the polymer. W ₁ ′, W ₂ ′,... Wn ′ are mass fractions of the respective monomers with respect to the total monomer components. T ₁ , T ₂ ,... Tn are glass transition temperatures (absolute temperatures) of homopolymers (homopolymers) composed of the respective monomer components.

Examples of the crosslinked coating polymer include a polymer obtained by polymerizing a crosslinkable monomer among the polymerizable monomers described above. Although it does not specifically limit as a crosslinkable monomer, For example, diethylene glycol di (meth) acrylate, a trimethylol propane tri (meth) acrylate, (meth) acrylic-acid glycidyl etc. are mentioned preferably.

Further, the solubility parameter (SP value) of the coating polymer is not particularly limited, but is preferably 7 to 11 from the viewpoint that the organic crystal coated with the coating polymer is dispersed without dissolving in the matrix polymer. is there. More preferably, it is 7.2-10.5, More preferably, it is 7.4-10.
The SP value of the coating polymer can be determined by, for example, the following Small formula.

In the formula, δ is the SP value of the polymer. Δe ₁ is a calculated value (kcal / mol) of evaporation energy of each monomer component constituting the polymer, and ΣΔe ₁ is a total value of the calculated values of all monomer components constituting the polymer. is there. ΔV _m is a calculated value (ml / mol) of the molecular volume of each monomer component constituting the polymer, and ΣΔV _m is the sum of the calculated values of all the monomer components constituting the polymer. . x is a molar distribution of each component of the monomer constituting the polymer.
Note that normally used calculation values can be used for the evaporation energy of the monomer component and the molecular volume of the monomer component.

In the emulsion polymerization, an emulsifier can be used. Although it does not specifically limit as the said emulsifier, Anionic, cationic, nonionic, amphoteric various emulsifiers, polymeric emulsifier, etc. are mentioned. These emulsifiers may be used alone or in combination of two or more. In each of the following emulsifiers, one kind may be used or two or more kinds may be used in combination.

The anionic emulsifier is not particularly limited. For example, polyoxyalkylene alkyl ether sulfate, polyoxyalkylene oleyl ether sodium sulfate, polyoxyalkylene alkylphenyl ether sulfate, alkyl diphenyl ether disulfonate, polyoxyalkylene (Mono, di, tri) styryl phenyl ether sulfate, polyoxyalkylene (mono, di, tri) benzyl phenyl ether sulfate, alkenyl succinate; sodium dodecyl sulfate, potassium dodecyl sulfate, ammonium alkyl sulfate, etc. Alkyl sulfate salt; sodium dodecyl polyglycol ether sulfate; sodium sulforicinoate; sulfonated paraffin Alkyl sulfonates such as sodium dodecyl benzene sulfonate, alkyl sulfonates such as alkali metal hydroxyethylene alkali metal sulfates; high alkyl naphthalene sulfonates; naphthalene sulfonic acid formalin condensates; sodium laurate, triethanolamine oleate, triethanolamine Fatty acid salts such as abietate; polyoxyalkyl ether sulfate ester; polyoxyethylene carboxylate sulfate ester salt; polyoxyethylene phenyl ether sulfate ester salt; succinic acid dialkyl ester sulfonate salt; polyoxyethylene alkylaryl sulfate salt Is mentioned.

The nonionic emulsifier is not particularly limited. For example, polyoxyethylene alkyl ether; polyoxyethylene alkyl aryl ether; sorbitan aliphatic ester; polyoxyethylene sorbitan aliphatic ester; aliphatic monoglyceride such as monolaurate of glycerol; Polyoxyethyleneoxypropylene copolymer; condensation products of ethylene oxide and aliphatic amines, amides or acids. A nonionic emulsifier having reactivity such as allyloxymethylalkoxyethylhydroxypolyoxyethylene can also be used.

The cationic emulsifier is not particularly limited, and examples thereof include dialkyldimethylammonium salts, ester-type dialkylammonium salts, amide-type dialkylammonium salts, and dialkylimidazolinium salts.

The amphoteric emulsifier is not particularly limited, and examples thereof include alkyldimethylaminoacetic acid betaine, alkyldimethylamine oxide, alkylcarboxymethylhydroxyethyl imidazolinium betaine, alkylamidopropyl betaine, and alkylhydroxysulfobetaine.

The polymer emulsifier is not particularly limited. For example, polyvinyl alcohol and modified products thereof; (meth) acrylic water-soluble polymer; hydroxyethyl (meth) acrylic water-soluble polymer; hydroxypropyl (meth) acrylic water solution Polymer; polyvinylpyrrolidone and the like.

Among the above emulsifiers, it is preferable to use a non-nonylphenyl emulsifier from the viewpoint of environment.
The amount of the emulsifier used may be set as appropriate depending on the type of emulsifier used and the type of monomer component. From the viewpoint of sufficient polymerization stability, for example, the total amount of polymerizable monomer components is 100 parts by mass. It is preferable that it is 0.5-10 mass parts with respect to. More preferably, they are 1 mass part or more and 8 mass parts or less, More preferably, they are 1.5 mass parts or more and 7 mass parts or less.

In the emulsion polymerization, a polymerization initiator can be used. The polymerization initiator is not particularly limited as long as it is a radical polymerization initiator. For example, peroxides such as hydrogen peroxide, potassium persulfate, sodium persulfate, ammonium persulfate, and potassium perphosphate These peroxides include ascorbic acid and its salts, erythorbic acid and its salts, tartaric acid and its salts, citric acid and its salts, sodium thiosulfate, sodium bisulfite, sodium pyrosulfite, Rongalite C (NaHSO ₂ .CH ₂ O · _{H 2} O), Rongalite _{Z (ZnSO 2 · CH 2 O} · H 2 O), Dekurorin _{(Zn (HSO 2 · CH 2} O) 2) redox initiators in combination a reducing agent such as; t- Butyl hydroperoxide, t-amyl hydroperoxide, t-hexyl hydroperoxide, p-menthane hydro Hydroperoxides such as peroxide and cumene hydroperoxide; Dialkyl peroxides such as di-t-butyl peroxide and di-t-amyl peroxide; Dibenzoyl peroxide, dioctanoyl peroxide, didecanoyl peroxide, didodecanoyl peroxide and the like Diacyl peroxides; peroxyesters such as t-butylperoxypivalate, t-amylperoxypivalate, t-butylperoxybenzoate; 2,2′-azobis (isobutyronitrile), 2,2′-azobis (2 -Methylbutyronitrile), 2,2'-azobis (2,4-dimethylvaleronitrile), 2,2'-azobis (4-methoxy-2,4-dimethylvaleronitrile), 2,2'-azobis ( Isobutyric acid) dimethyl, 4,4'-azobis 4-cyanovaleric acid), 2,2′-azobis (2-methylpropionamidine) dihydrochloride, 2,2′-azobis [N- (2-carboxyethyl) -2-methylpropionamidine] n hydrate 2,2′-azobis {2-methyl-N- [2- (1-hydroxybutyl)] propionamide}, 2,2′-azobis {2-methyl-N- [1,1-bis (hydroxymethyl) ) -2-hydroxyethyl] propionamide}, 2,2′-azobis (1-imino-1-pyrrolidino-2-ethylpropane) dihydrochloride, 2,2′-azobis [2- (2-imidazoline-2) -Yl) propane], 2,2'-azobis [2- (2-imidazolin-2-yl) propane] dihydrochloride, 2,2'-azobis [2- (2-imidazolin-2-yl) propane] Disulfate dihydrate, 2, '-Azobis {2- [1- (2-hydroxyethyl) -2-imidazolin-2-yl] propane} dihydrochloride, 2,2'-azobis [2- (5-methyl-2-imidazoline-2- Yl) propane] dihydrochloride, azo compounds such as 1,1′-azobis (cyclohexane-1-carbonitrile); and the like. These polymerization initiators may be used alone or in combination of two or more.

The amount of the polymerization initiator used may be appropriately adjusted according to the amount of the polymerizable monomer used, and is not particularly limited. For example, 0.1 to 4 parts by weight with respect to 100 parts by weight of the polymerizable monomer. Part. More preferably, they are 0.15 mass part or more and 3 mass parts or less, More preferably, they are 0.2 mass part or more and 2 mass parts or less.

The aqueous medium used in the polymerization reaction is not particularly limited, and examples thereof include water and a mixed solvent of water and a water-miscible organic solvent.
The water-miscible organic solvent is not particularly limited, and examples thereof include alcohols such as methanol, ethanol, isopropyl alcohol, n-propyl alcohol, and allyl alcohol; ethylene glycol, propylene glycol, butylene glycol, hexylene glycol, and pentane. Glycols such as diol, hexanediol, heptanediol, and dipropylene glycol; ketones such as acetone, methyl ethyl ketone, and methyl propyl ketone; esters such as methyl formate, ethyl formate, methyl acetate, and methyl acetoacetate; diethylene glycol monomethyl ether, diethylene glycol Monoethyl ether, diethylene glycol dimethyl ether, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether , Ethers such as dipropylene glycol monomethyl ether; and the like. These organic solvents may be used alone or in combination of two or more. Among these organic solvents, an organic solvent that dissolves the monomer component but does not dissolve the polymer synthesized from the monomer component is preferable.

When a mixed solvent of water and a water-miscible organic solvent is used as the aqueous medium, the water-miscible organic solvent is used in an amount of 1 to 100 with respect to 100 parts by mass of water because there is no fear of elution of the crystal. It is preferable that it is a mass part. More preferably, it is 2-75 mass parts, More preferably, it is 3-50 mass parts.

Although the reaction temperature of a polymerization reaction is not specifically limited, For example, it is preferable that it is 60-95 degreeC from the point of speeding up a polymerization rate or the boiling temperature of water. More preferably, it is 70 degreeC or more and 90 degrees C or less. Further, the reaction time of the polymerization reaction may be appropriately adjusted according to the amount of the crystalline substance and the polymerizable monomer used, and is not particularly limited. For example, from the viewpoint of preventing heat generation due to rapid reaction and reducing the residual monomer. 10 hours is preferable. More preferably, it is 4 hours or more and 8 hours or less.

In addition, after manufacturing the dispersion (emulsion) of an organic crystal by emulsion polymerization, an emulsion can also be neutralized with a neutralizing agent. As a result, the emulsion is stabilized. The neutralizing agent is not particularly limited, and for example, tertiary amines such as triethanolamine, dimethylethanolamine, diethylethanolamine and morpholine; diglycolamine, aqueous ammonia; sodium hydroxide and the like can be used. These may be used alone or in combination of two or more.

In addition, as described above, when the organic low-molecular compound constituting the crystal body has a reactive functional group (functional group A) and the coating polymer also has a reactive functional group (functional group B), What is necessary is just to use the said functional group applied when couple | bonding an organic compound and a polymer.
Examples of the functional group A include a hydroxyl group, a phenol group, a hydroxyl group, a carboxyl group, an amino group, and a thiol group. Examples of the functional group B include a glycidyl group, an isocyanate group, an oxazoline group, an aziridine group, and a carbodiimide group. Each may be one type or two or more types.
In addition, the case where the organic low molecular weight compound has the functional group exemplified in the functional group B and the coating polymer has the functional group exemplified in the functional group A is also included in the present invention.

In the present invention, since a crystal containing an organic substance is used, the binding property with the polymer is remarkably better than when using inorganic particles or the like, but the bond between the crystal and the polymer layer is stronger. In order to do so, the surface of the crystal is treated in advance with chromic acid, silane coupling agent, sodium hypochlorite, sodium toluenesulfonate, sodium hydroxide, potassium permanganate, ammonium persulfate, corona discharge, etc. Functional groups can also be introduced.

After the polymerization reaction, an aqueous dispersion of organic crystals in which the surface of the crystal body is coated with a polymer is obtained. The obtained aqueous dispersion may be used as it is. For example, the polymerization reaction solution is centrifuged to separate a supernatant and a precipitate, and the precipitate is recovered and dried to obtain a polymer-coated organic dispersion. Crystals may be obtained and used in the form of powder.
The method for drying the polymer-coated organic crystals may be appropriately selected from conventionally known drying methods, and is not particularly limited. For example, natural drying, heat drying, reduced pressure drying, spray drying, etc. Is mentioned. The obtained polymer-coated organic crystals may be used as a powder or may be used in the form of a dispersion redispersed in an appropriate solvent.

The method for redispersing the polymer-coated organic crystals in the dispersion medium may be appropriately selected from conventionally known dispersion methods and is not particularly limited. For example, a stirrer, ball mill, sand mill, ultrasonic homogenizer, etc. The method using is mentioned.

When the polymer-coated organic crystals are in the form of a dispersion, and the polymer-coated organic crystals are dispersed in different dispersion media, for example, the dispersion is filtered, centrifuged, or the dispersion medium is evaporated. The polymer-coated organic crystals are separated, mixed with the dispersion medium to be replaced, and then dispersed using the method described above, or the dispersion is heated to form the dispersion medium. It is possible to employ a heating solvent substitution method or the like in which a dispersion medium to be substituted is mixed while part or all of the solvent is evaporated and distilled off.

The organic crystals in the aqueous dispersion, powder, and dispersion in other solvents obtained as described above are obtained by coating the surface of the crystal with a polymer.
Using the organic crystals, the dispersions of the above-described first to third embodiments can be obtained.

The method for producing the dispersion according to Embodiment 1 is not particularly limited. For example, in an aqueous dispersion containing organic crystals coated with the coating polymer obtained as described above, the organic crystals are coated. A method of forming a matrix polymer by further subjecting a monomer for forming a matrix polymer to emulsion polymerization on the surface of the polymer in the same manner as described above.
Alternatively, the organic crystal coated with the coating polymer is made into powder without using a dispersant, and then the matrix-forming monomer is subjected to suspension polymerization in a state of being mechanically dispersed. The organic crystal can be produced in the form of an aqueous dispersion.

The matrix polymer incompatible with the coating polymer is not particularly limited, and examples thereof include a polymer obtained by polymerizing the same polymerizable monomer as exemplified in the coating polymer. Preferably, a polymer obtained by polymerizing at least one polymerizable monomer selected from vinyl alcohol, vinyl pyrrolidone, (meth) acrylic acid and the like which are raw materials for the water-soluble polymer; (meth) acrylic acid ester; and styrene Is mentioned.

Although the examples of the polymerizable monomers used in the coating polymer and the matrix polymer are the same, actually, the matrix polymer has a solubility parameter (SP value) different from the polymer used in the coating polymer among the above examples. It is preferred to select a combination of monomers so that
The difference in SP value between the coating polymer and the matrix polymer is preferably 0.2 or more. The SP value difference is more preferably 0.3 or more, and still more preferably 0.4 or more. The SP value difference means a value obtained by subtracting the smaller SP value from the larger SP value of the two SP values.
The SP value of the matrix polymer is not particularly limited, but is preferably 7 to 11 from the viewpoint that the organic crystals coated with the coating polymer are dispersed without dissolving in the matrix polymer. More preferably, it is 7.2-10.5, More preferably, it is 7.4-10.
The SP value can be obtained by the same method as described above.

The weight average molecular weight of the matrix polymer is preferably 20,000 to 1,000,000. When it is within the above range, when it is used as a coating film, it is excellent in film formability and has a sufficient strength. The said weight average molecular weight becomes like this. More preferably, it is 40,000 or more and 750,000 or less, More preferably, it is 60,000 or more and 500,000 or less.
The weight average molecular weight can be determined by the same method as described above.
In addition, the matrix polymer preferably has a glass transition temperature of -20 to 50 ° C from the viewpoint of film formability and strength of the coating film. More preferably, it is -15-45 degreeC, More preferably, it is -10-40 degreeC.
The glass transition temperature can be determined by the same method as described above.

Furthermore, in the aqueous dispersion, powder, and dispersion in other solvents obtained as described above, the organic crystal in which the surface of the crystal is coated with the coating polymer is contained in a matrix polymer that is incompatible with the coating polymer. A dispersion (hereinafter also referred to as a polymer dispersion) in the form dispersed in (Embodiment 2 described above) is also possible.

A method for producing a dispersion of organic crystals coated with the above coating polymer into a matrix polymer is not particularly limited. For example, an aqueous dispersion of organic crystals coated with a coating polymer is powdered as described above. And a method of redispersing it in a matrix polymer. Alternatively, a heating solvent in which a matrix polymer, which is a dispersion medium to be replaced, is mixed while heating a water dispersion of an organic crystal to evaporate a part or all of the dispersion medium constituting the dispersion. Substitution method etc. are mentioned.

The method for producing the organic crystal of Embodiment 3 is not particularly limited. For example, an aqueous dispersion containing the organic crystal coated with the coating polymer obtained as described above and a matrix polymer are used. Examples include a method of mixing an aqueous dispersion containing a matrix polymer obtained by emulsion polymerization.

Among the above-mentioned forms, the form of powder is the form of the organic crystal of the present invention.
Moreover, the composition containing the said organic crystal is also one of this invention. Among the above-mentioned forms, those in the form of dispersions (including water dispersions, dispersions in other dispersion media, and polymer dispersions) are classified as the organic crystal-containing compositions.
The organic crystal-containing composition contains the organic crystal or the organic crystal and polymer, but may further contain other components.

When other components are included, the proportion of the other components in 100% by mass of the whole composition is preferably 90% by mass or less, and more preferably 85% by mass or less. In addition, when the said composition is apply | coated here, the other component here means the non volatile matter (solid content) which remains in a coating film after heat-drying, and an aqueous medium etc. are not contained.

The organic crystal-containing composition of the present invention is a solid composition in which the content ratio of the crystal is a sum of the polymer and the crystal from the viewpoint of imparting the performance expressed by the crystal to the coating while maintaining the strength of the coating In 100% by mass, 40 to 80% by mass is preferable, and more preferably 50 to 70% by mass.
In addition, solid content here means the non volatile matter which remains in a coating film after heat-drying, when the said composition is apply | coated.

Although it does not specifically limit as another component, For example, Solvent; Filler; Dispersant; Defoamer; Colorant; Anticorrosive pigment; Plasticizer; Stabilizer; Wetting agent; Agents, antifungal agents, ultraviolet absorbers, antistatic agents, foaming agents, viscosity modifiers, and the like, and one or more of these can be used.
In addition, the said other component can be mixed with the said organic crystal using a butterfly mixer, a planetary mixer, a spiral mixer, a kneader, a dissolver etc., for example.

Examples of the solvent include ethylene glycol, butyl cellosolve, butyl carbitol, butyl carbitol acetate, and the like. What is necessary is just to set suitably as a compounding quantity of a solvent so that the organic crystal density | concentration in a composition may become the range mentioned above.

Examples of the filler include inorganic fillers such as calcium carbonate, kaolin, silica, talc, barium sulfate, alumina, iron oxide, titanium oxide, glass talk, magnesium carbonate, aluminum hydroxide, talc, diatomaceous earth, and clay; glass Examples of such inorganic fillers include flakes and mica; and fibrous inorganic fillers such as metal oxide whiskers and glass fibers. As a compounding quantity of a filler, it is preferable to set it as 10-700 mass parts with respect to a total of 100 mass parts (solid content) of a polymer and a crystal, More preferably, it is 50-600 mass parts, More preferably 100 to 550 parts by mass.

Examples of the dispersant include inorganic dispersants such as sodium hexametaphosphate and sodium tripolyphosphate, and organic dispersants such as polycarboxylic acid-based dispersants.
Examples of the antifoaming agent include silicon-based antifoaming agents.

In addition, as described above, a coating film containing the organic crystal is also one aspect of the present invention. In other words, examples of the coating film include a coating film formed by forming the organic crystals and a coating film formed by dispersing the organic crystals in a polymer matrix.

Examples of the coating film formed by forming the organic crystal include a coating film obtained by using the above-described aqueous dispersion of organic crystals or a dispersion in another dispersion medium (Embodiments 1 and 3). Can be mentioned.
As a coating film obtained by dispersing the organic crystals in a polymer matrix, for example, a coating film obtained by using a dispersion in which organic crystals coated with the above-described coating polymer are dispersed in a matrix polymer (Embodiment 2). ) And the like.

The said coating film can be formed by apply | coating the said organic crystal containing composition to a base material, for example, and drying. Although it does not specifically limit as a base material, For example, an aluminum plate, a steel plate, a galvanized steel plate, a glass plate, a slate board, a Teflon (trademark) board etc. are mentioned. Moreover, as a method of apply | coating an organic crystal containing composition to a base material, it can apply | coat using a brush, a spatula, an air spray, an airless spray, a mortar gun, a ricin gun etc., for example.

Since the organic crystal of the present invention is formed by coating the surface of a crystal containing an organic substance with a polymer, the organic crystal can be prevented by preventing a change in performance or deterioration over time due to aggregation, deformation of the organic crystal, bleed-out, etc. The organic crystal can sufficiently exhibit various characteristics possessed over time and can be suitably used in various applications. In addition, the organic crystal can be suitably used as a dielectric, ferroelectric, ultraviolet absorber, infrared absorber, magnetic body, conductor, and light emitter.

It is a conceptual diagram of the said Embodiment 1. FIG. It is a conceptual diagram of the said Embodiment 2. FIG. It is a conceptual diagram of the said Embodiment 3. FIG. It is a conceptual diagram which shows the major axis and minor axis of a particle | grain with a large aspect ratio.

The present invention will be described in more detail with reference to the following examples. However, the present invention is not limited to these examples. Unless otherwise specified, “part” means “part by mass” and “%” means “% by mass”.

In the following examples, various physical properties and the like were evaluated as follows.
<Average particle size>
Using a SEM (manufactured by Hitachi High-Tech, FE-SEM, S-4800), measuring the particle size by analyzing the measurement image, and calculating the average value of these, the average particle size of the crystal Asked. In the case of particles having an aspect ratio larger than 1, the major axis of 50 particles was measured and the average value thereof was calculated.
<Aspect ratio>
Using a SEM (manufactured by Hitachi High-Tech, FE-SEM, S-4800), the major axis and minor axis of 50 particles are measured by analyzing the measurement image, and the average value of each major axis and minor axis is calculated. Thus, the aspect ratio (average value of major axis / average value of minor axis) of the crystal was obtained.

Production Example 1
Crystallization by reprecipitation was performed by adding 4,4′-thiobis (2-methyl-6-tert-butylphenol) dissolved in acetone to 10 times the amount of water. After filtration, vacuum drying was performed at 80 ° C. for 3 hours to obtain a crystal body (1) having a particle diameter of 20 μm and an aspect ratio of 10.

Production Example 2
80 parts of deionized water was charged into a polymerization vessel equipped with a stirrer, a reflux condenser, a thermometer, a nitrogen inlet tube and a dropping funnel. Thereafter, the internal temperature was raised to 80 ° C. while stirring under a nitrogen gas stream. To the dropping funnel, 56.5 parts of styrene, 42 parts of 2-ethylhexyl acrylate, 1.5 parts of acrylic acid, 15 parts of Latemul PD-104 (trade name, manufactured by Kao Corporation, 20% aqueous solution of polyoxyalkylene alkenyl ether ammonium sulfate) and desorption A monomer emulsion consisting of 30 parts of ionic water was charged. Next, while maintaining the internal temperature of the polymerization vessel at 80 ° C., 1 part of the monomer emulsion and 4 parts of 5% potassium persulfate aqueous solution were added to initiate initial polymerization. After 20 minutes, the remaining monomer emulsion was uniformly added dropwise over 60 minutes while maintaining the inside of the reaction system at 80 ° C. After completion of dropping, the temperature was maintained at 80 ° C. for 60 minutes.
After cooling the obtained reaction liquid to room temperature, 1 part of 25% aqueous ammonia was added to obtain an emulsion (1) having a nonvolatile content of 44.2%.

Example 1
Crystallization by reprecipitation was performed by adding α, α′-bis (4-hydroxyphenyl) -1,4-diisopropylbenzene dissolved in acetone to 10 times the amount of water. After filtration, vacuum drying was performed at 80 ° C. for 3 hours to obtain a crystal (3) having a particle diameter of 11 μm and an aspect ratio of 8.
A polymerizer equipped with a stirrer, a reflux condenser, a thermometer, a nitrogen inlet tube and a dropping funnel, 600 parts of deionized water, 45 parts of Latem PD-104 (trade name, manufactured by Kao Corporation, 20% aqueous solution), the above crystal 300 copies were loaded. Thereafter, the internal temperature was raised to 80 ° C. while stirring under a nitrogen gas stream.
In a dropping funnel, 32.5 parts of styrene, 14.2 parts of 2-ethylhexyl acrylate, 0.8 parts of acrylic acid, 2.5 parts of diethylene glycol dimethacrylate, Latemul PD-104 (trade name, manufactured by Kao Corporation, 20% aqueous solution) 7 A monomer emulsion consisting of 5 parts and 15 parts deionized water was charged. Next, while maintaining the internal temperature of the polymerization vessel at 80 ° C., 1 part of the monomer emulsion and 4 parts of 5% potassium persulfate aqueous solution were added to initiate initial polymerization. After 20 minutes, the remaining monomer emulsion was uniformly added dropwise over 60 minutes while maintaining the inside of the reaction system at 80 ° C. After completion of dropping, the temperature was maintained at 80 ° C. for 60 minutes.
After cooling the obtained reaction liquid to room temperature, 0.5 part of 25% aqueous ammonia was added to obtain an organic crystal emulsion (2) having a nonvolatile content of 35.2%.

Example 2
Crystallization by reprecipitation was performed by adding 4,4′-thiobis (2-methyl-6-tert-butylphenol) dissolved in acetone to 10 times the amount of water. After filtration, vacuum drying was performed at 80 ° C. for 3 hours to obtain a crystal body (1) having a particle diameter of 20 μm and an aspect ratio of 10.
A polymerizer equipped with a stirrer, reflux condenser, thermometer, nitrogen inlet tube and dropping funnel, 400 parts of deionized water, 30 parts of Latemul PD-104 (trade name, manufactured by Kao Corporation, 20% aqueous solution), the above crystal 200 copies were prepared. Thereafter, the internal temperature was raised to 80 ° C. while stirring under a nitrogen gas stream.
First stage dropping: 65 parts methyl methacrylate, 28.5 parts 2-ethylhexyl acrylate, 1.5 parts acrylic acid, 5 parts diethylene glycol dimethacrylate, Latemul PD-104 (trade name, manufactured by Kao Corporation, 20%) A monomer emulsion consisting of 15 parts aqueous solution and 30 parts deionized water was charged. Next, while maintaining the internal temperature of the polymerization vessel at 80 ° C., 1 part of the monomer emulsion and 4 parts of 5% potassium persulfate aqueous solution were added to initiate initial polymerization. After 20 minutes, the remaining monomer emulsion was uniformly added dropwise over 60 minutes while maintaining the inside of the reaction system at 80 ° C. After completion of the first-stage dropping, the temperature was maintained at 80 ° C. for 40 minutes.
Second stage dropping: 97 parts methyl methacrylate, 100 parts n-butyl acrylate, 3 parts acrylic acid, 30 parts Latemu PD-104 (trade name, manufactured by Kao Corporation, 20% aqueous solution) and 60 parts deionized water in a dropping funnel Was added 40 parts after the completion of the first-stage dropping, and 4 parts of 5% aqueous potassium persulfate solution was immediately added, and the monomer emulsion in the dropping funnel was immediately dropped uniformly over 120 minutes. After completion of the second-stage dropping, the temperature was maintained at 80 ° C. for 60 minutes.
After cooling the obtained reaction liquid to room temperature, 3 parts of 25% aqueous ammonia was added to obtain an organic crystal emulsion (3) having a nonvolatile content of 47.6%.
The emulsion was applied on a Teflon (registered trademark) plate having a smooth surface so that the film thickness after drying was 0.2 mm, and dried at 80 ° C. for 12 hours to obtain a dried coating film.

Example 3
Crystallization by reprecipitation was performed by adding N, N-dicyclohexylbenzothiazole-2-sulfenamide dissolved in acetone to 10 times the amount of water. After filtration, vacuum drying was performed at 80 ° C. for 3 hours to obtain a crystal body (2) having a particle diameter of 18 μm and an aspect ratio of 11.
A polymerizer equipped with a stirrer, reflux condenser, thermometer, nitrogen inlet and dropping funnel, 200 parts of deionized water, 15 parts of Latem PD-104 (trade name, manufactured by Kao Corporation, 20% aqueous solution), the above crystal 100 parts were charged. Thereafter, the internal temperature was raised to 80 ° C. while stirring under a nitrogen gas stream.
First drop: 35 parts of styrene, 14.2 parts of 2-ethylhexyl acrylate, 0.8 part of acrylic acid, 7.5 parts of Latemul PD-104 (trade name, manufactured by Kao Corporation, 20% aqueous solution) and A monomer emulsion consisting of 15 parts deionized water was charged. Next, while maintaining the internal temperature of the polymerization vessel at 80 ° C., 1 part of the monomer emulsion and 4 parts of 5% potassium persulfate aqueous solution were added to initiate initial polymerization. After 20 minutes, the remaining monomer emulsion was uniformly added dropwise over 60 minutes while maintaining the inside of the reaction system at 80 ° C. After completion of the first-stage dropping, the temperature was maintained at 80 ° C. for 40 minutes.
Second stage dropping: Performed in the same manner as the second stage dropping in Example 2.
After cooling the resulting reaction liquid to room temperature, 2.5 parts of 25% aqueous ammonia was added to obtain an organic crystal emulsion (4) having a nonvolatile content of 52.3%.
The emulsion was applied on a Teflon (registered trademark) plate having a smooth surface so that the film thickness after drying was 0.2 mm, and dried at 80 ° C. for 12 hours to obtain a dried coating film.

Example 4
Using an emulsion mixed so that the ratio of the nonvolatile content is emulsion (2): emulsion (1) = 7: 2, the film thickness after drying is 0.2 mm on a Teflon (registered trademark) plate having a smooth surface. And dried at 80 ° C. for 12 hours to obtain a dried coating film.

Comparative Example 1
Using an emulsion mixed so that the non-volatile content ratio is crystal (1): emulsion (1) = 1: 1, the film thickness after drying is 0.2 mm on a Teflon (registered trademark) plate having a smooth surface. And dried at 80 ° C. for 12 hours to obtain a dried coating film.

The crystallinity and crystal shape were evaluated as follows. The results are shown in Table 1.
<Crystallinity>
In the coating films obtained in Examples 2 to 4 and Comparative Example 1, the degree of crystallization immediately after preparation of the coating film obtained by X-ray diffraction was set to 100, and changes with time were evaluated.
X-ray diffraction uses RINT-TTRIII (manufactured by Rigaku Corporation), CuKα ray, voltage 50 kV, current 300 mA, scan speed 10 degrees / minute, sampling width 0.02 degrees, scanning range 5 to 75 degrees, scanning axis 2θ / Measurement was performed under the condition of θ and the number of times of integration.
The evaluation criteria are as follows.
100-90: (circle), 50-80: (triangle | delta), 50 or less: x.

<Crystal shape>
Changes in the shape of the crystal observed with an electron microscope were evaluated.
The evaluation criteria are as follows.
No change: ◯, shape changed: Δ, shape changed greatly or crystal disappeared: x.

Since the organic crystals in the coating films of Examples 2 to 4 are coated with a polymer on the surface of the crystal body, the crystallinity and crystal shape change even after storage at 40 ° C. for 1 month and 3 months. I couldn't see it. On the other hand, since the organic crystal in the coating film of Comparative Example 1 does not cover the surface of the crystal body with the polymer, when it is stored at 40 ° C. for 1 month and 3 months, its crystallinity and crystal shape with time. Has changed significantly.
In this way, by forming an organic crystal formed by coating the surface of the crystal with a polymer, the organic crystal can be prevented from changing or degrading over time due to aggregation, shape loss, bleedout, etc. of the organic crystal. It is considered that the mechanism of action that fully exerts the various characteristics possessed over time is the same.
Therefore, it can be said from the results of the above-described embodiments that the present invention can be applied in the entire technical scope of the present invention and in various forms disclosed in the present specification, and can exhibit advantageous effects.

1: Crystal 2: Coating polymer 3: Matrix polymer 4: Dispersion medium 5: Long diameter 6: Short diameter

Claims (6)

An organic crystal composed of a crystal containing organic matter,
The crystal has an aspect ratio of 2 or more,
An organic crystal characterized in that the surface of the crystal is coated with a polymer and further covered with a matrix polymer. The organic crystal according to claim 1 , wherein the crystal has an average particle size of 0.1 to 100 μm. The organic crystal according to claim 1 or 2 , wherein the organic crystal has a mass ratio of a polymer and a crystal body of 1: 9 to 9: 1. The organic crystals, dielectric, ferroelectric, ultraviolet absorber, infrared absorber, a magnetic material, an organic crystal according to any one of claims 1 to 3, characterized in that a conductor or light emitters. A method for producing a coating film comprising the organic crystal according to any one of claims 1 to 4 ,
The production method includes a step of forming a film of an organic crystal and / or a step of dispersing the organic crystal in a polymer matrix. Dispersion characterized by comprising dispersing the organic crystal of the dispersion medium to any one of claims 1 to 4.

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