WO2017074152A1 - Microparticles containing color nanocomposite and method for manufacturing same - Google Patents

Abstract

The present invention relates to microparticles which are rearranged by the application of an electric field or a magnetic field and contain a color nanocomposite including nanoparticles, and to a method for manufacturing the microparticles, wherein, in the microparticles, the pencil hardness in a dry powder state is 4B or less; and the pore volume of the region of 5 nm or less is 20% or less of the total pore volume in the pore size distribution according to the specific surface area measurement using nitrogen gas, and the pore volume of the region of 3 nm or less is 20% or less of the total pore volume in the pore distribution according to the specific surface area measurement using argon gas.

Description

Micro particles containing color nanocomposites and methods for their preparation.

The present invention relates to a color nanocomposite and a method for manufacturing the same, a microparticle containing the color nanocomposite and a method for manufacturing the same, and more particularly, a color nanocomposite and a method for producing the color change in response to an electric or magnetic field and The core includes the color nanocomposite and the shell (shell) relates to the microparticles made of a high elastic and hard polymer material and a method of manufacturing the same.

Nanoparticles exhibit unique properties that are not found in particles larger than micron size by the effect of quantum size, and exhibit excellent luminescent properties, magnetic properties, catalytic properties, etc., due to their relatively large surface area, even when they have the same properties as the bulk state.

In the past decades, various nanoparticle synthesis methods have been studied. Among them, magnetic nanoparticles not only have excellent magnetic properties, but when the particle size is about 20 nm or less, individual nanoparticles are superparamagnetic ( It is attracting attention that it will have a variety of applications due to its superparamagnetics.

That is, the superparamagnetic nanoparticles are normally dispersed without showing the general magnetic properties, but the magnetic field moments of the nanoparticles are arranged in the same direction by the external magnetic field, so that the spacing between the nanoparticles can be controlled.

As a method of synthesizing superparamagnetic nanoparticles having excellent magnetic properties and uniform size, reduction pyrolysis of metal salts or complex compounds in organic solvents is widely known (US Patent Nos. 6,676,729 and 7,407,527).

However, since superparamagnetic nanoparticles synthesized by this pyrolysis method are protected or strongly bound by ligands of long saturated hydrocarbon chains, surface treatment for application is difficult and organic ligands present on the surface inhibit the development of superparamagnetic properties. And prevents the nanoparticle particles from dispersing in aqueous solution to limit biological applications.

As a method for overcoming this, methods for forming nanocluster colloids by aggregating themselves as the reaction proceeds, rather than aggregating individual nanoparticles using organic / inorganic materials (Angew. Chem. Int. Ed., 2005, 44, 2782., J. Am. Chem. Soc., 2009, 131, 12900.)

In addition, various compounding ratios for synthesizing precursor materials in order to increase the mass productivity of nanocluster production are also studied. That is, the size of the magnetic nanoclusters is controlled according to the amount of reactants or the ratio between reactants, reaction temperature and time, and the magnetic properties are increased according to the type and amount of dissimilar metals, or superparamagnetic, paramagnetic, ferromagnetic, and antiferromagnetic A method of manufacturing a magnetic nanocluster that can be modified in various ways has been developed (Korea Patent Publication No. 10-1151147)

The particle size of the monodisperse superparamagnetic nanoparticle clusters prepared by the above process is controlled to about 150 nm and stably dispersed to apply a magnetic field so that the color of the dispersed colloid changes according to the strength of the magnetic field, and brown color increases as the strength of the magnetic field increases. Nanoparticle colloids become blue, making them a versatile color-variable application.

For example, by stacking a patterned magnetic layer on top of a display layer of a color display material including a color nanocomposite or by stacking a magnetic layer on a bottom, various colors may be changed through magnetic field discoloration compared to a display layer without a magnetic layer pattern. In addition, the color change material may further improve color change and color diversity by realizing the discoloration effect by the proximity of an external magnetic material, and the color display material includes a separate material layer such as a magnetization material instead of a medium of the color display material. When the magnetic field is not applied from outside, color is not realized or discoloration does not occur, and photonic crystals or particles are arranged and spaced stably by an externally applied magnetic field. In addition, images and information can be retained even after the magnetic field is removed.

However, for such various types of applications, nano-composites with very high visibility and very uniform particle sizes are required due to the large color change caused by the application of electric or magnetic fields. Insufficient to implement

Meanwhile, as part of a method for protecting the material itself from being polluted, damaged or changed according to the usage of the material, or isolating and keeping it from reacting with other materials, the pharmaceutical industry, pesticide-related industry and display fields, etc. There are various applications of micro particles.

In particular, when the nanoparticles themselves are in a solution state dispersed in a certain medium, the microparticles are often applied because of the difficulty in manufacturing a general printing apparatus and a film therefor.

On the other hand, photonic crystal is an example of nanoparticles that must include a liquid solvent in realizing material properties. When the magnetic field energy is given, the nanoparticles move directly and reflect the color corresponding to a specific wavelength as the arrangement and spacing of the particles change.

Inks containing photonic crystal nanoparticles or nanocomposites that change color in response to external magnetic fields are in a liquid state and thus have limited applications. For various applications, it is essential to prevent leakage of ink and to maintain its properties, and at the same time, it is required for easy storage for a long time and low elasticity and rigid properties of the wall covering the ink so that it can be easily printed on various substrates.

Among chemical microparticles, three chemical approaches are commonly used: coacervation, interfacial polymerization, and in situ polymerization.

The coacervation method uses a highly flexible gelatinous polymer as the wall material of the particles, thus easily forming a closed packing structure between the particles, thereby facilitating the production of the film. Long-term storage is poor due to the phenomenon, it is difficult to apply to silk screen printing applicable to various substrates. In the case of the interfacial polymerization method, since hydrophobic ink is used as a wall material such as silica (SiO ₂ ) in an aqueous solution, it has process limitations such as hardening of the wall material and difficulty in controlling particle size.

In-situ polymerization method is simple in the process step and because the high degree of hardening of the wall material constituting the particles produced, there is little cohesion phenomenon between the particles when stored in the water phase, it is easy to dry and stored even in the powder state. In addition, silk screen printing is possible on various substrates, such as paper, porcelain surfaces, cloth, and the like.

Korean Patent Laid-Open Publication Nos. 10-2013-0093438 and 10-2014-0120219 disclose a method for preparing a capsule including a photonic crystal dispersion, but the photonic crystal dispersion is physically applied to the photonic crystal particles as a wall material. Since it shows the effect of supporting by using a polymeric material, it has not been disclosed until the method of obtaining micro-particles that can be easily printed by producing a particle form having a wall material having a low elasticity and a hard and deformable shape of the capsule itself.

 Therefore, there is a need for manufacturing microparticles having a low elasticity and hardening of the wall material to facilitate storage and printability of the nanocomposite whose color is changed by application of an electric or magnetic field.

The present invention has been made to solve the problems of the prior art as described above, and an object thereof is to provide a color nanocomposite having a uniform particle distribution and a method of manufacturing the same.

In addition, the present invention exhibits a characteristic in which the color difference (ΔE ^* _ab ) before and after application of the electric or magnetic field according to the color coordinates of the CIE color system is 2.2 or more and the full width at half maximum (FWHM) of the particle size distribution curve is 30 nm or less. Another object is to provide a color nanocomposite having a large color change and a very uniform particle size by applying a magnetic field.

Another object of the present invention is to provide a microparticle including the nanocomposite in a core and a shell having a low elasticity and a hard polymer material, and a method of manufacturing the same.

In addition, another object of the present invention is to provide long-term storage in the water phase or the microparticles including the nanocomposite discolored by the application of an electric or magnetic field or to be dried at a high temperature to have a storage even in the powder state.

Another object of the present invention is to provide microparticles that can be applied to various types of printing or coating processes through microparticles including color nanocomposites capable of realizing various colors.

The color nanocomposite according to the present invention relates to a color nanocomposite whose color is varied by application of an electric or magnetic field, wherein the color nanocomposite has a color difference (ΔE ^* _ab ) before and after application of an electric or magnetic field according to a color coordinate of a CIE color system. 2.2 or more, full width at half maximum (FWHM) of the particle size distribution curve is 30 nm or less, the zeta potential value of the water dispersion state of the color nanocomposite is more than four times compared to the water dispersion state of the nanoparticles It is characterized by flying.

In addition, the color nanocomposite may be dispersed in a polar or nonpolar medium and rearranged or changed in charge state by application of an electric or magnetic field, wherein the medium may include a dye or a pigment.

The color nanocomposite of the present invention may be a mixture of colorant particles and nanoparticles coated with a hydrophobic material, may be composed of nanoparticles coated with a colorant, and may be particles in which colorant particles and nanoparticles are aggregated.

Method for producing a color nanocomposite according to the present invention comprises the steps of preparing a mixture by mixing the colorant particles and nanoparticles; Mixing a hydrophobic material in the mixture to form a miniemulsion; And polymerizing the miniemulsion and a monomer.

In this case, the monomer is styrene (pyridine), pyridine (pyrrole), aniline (aniline), pyrrolidone (pyrrolidone), acrylic acid (acrylate), urethane (urethane), thiophene, carbazole It may be any one or more of (carbazole), fluorene (fluorene), vinyl alcohol (vinylalcohol), ethylene glycol (ethylene glycol), ethoxy acrylate (ethoxy acrylate).

In addition, the polymerization may be carried out by adding a droplet of the miniemulsion to the medium, and may be carried out by preparing a suspension of the hydrophobic material and the colorant particles, and then adding an initiator.

In addition, preparing a nanoparticle surface-modified (수식) surface of the nanoparticles with a material containing a reactive group; Preparing a dispersion by mixing the surface-modified nanoparticles and colorant particles; It can be prepared, including; the surface-modified nanoparticles and the adsorption reaction of the colorant particles.

In addition, modifying the surface of the nanoparticles and colorant particles; Preparing a dispersion by mixing the colorant particles and the nanoparticles; It may be prepared, including; the step of causing the adsorption reaction of the colorant particles and nanoparticles.

In addition, mixing the nanoparticle cluster and the colorant particles; It may be prepared to include; a step of causing an aggregation reaction of the nanoparticle cluster and the colorant particles.

In this case, the nanoparticle cluster and the colorant particles are characterized in that the difference (ΔD50) and the difference (ΔDm) of the average particle diameter according to the particle size distribution curve is 5nm or less.

In the manufacturing method of the present invention, the nanoparticles are silicon (Si), titanium (Ti), barium (Ba), strontium (Sr), iron (Fe), nickel (Ni), cobalt (Co), lead (Pb) ), Aluminum (Al), copper (Cu), silver (Ag), gold (Au), tungsten (W), molybdenum (Mo), zinc (Zn), zirconium (Zr) or one or more metals thereof It may be a nitride or oxide of, the colorant particles may be any one or more of dye particles, pigment particles, surface-modified carbon nanoparticles, graphite, surface-modified graphene oxide particles.

In addition, the dye particles are particles consisting of any one or more of azo dyes, anthraquinone dyes, carbonium dyes, indigo dyes, sulfide dyes, phthalocyanine dyes, the pigment particles are pigmented titanium oxide (titanium dioxide), Zinc oxide, lithopon, zinc sulfonate, chrome yellow, zinc chromate, red oxide of iron, red lead, cadmium ( cardmium red, molybdate chrome orange, milori blue, pressian blue, iron blue, cobalt blue, chrome green, chrome hydroxide, zinc green ), Silver powder, bronze powder, fluorescent pigment, pearl pigment or any one or more of inorganic pigments, or insoluble azo, soluble azo, phthalocyanine, quinacridone, dioxazine, isoindoli Paddy field, vat dye system, phylcholine series, fluorine System, it may be a quinophthalone-based, any of metal complexes or more organic pigments.

In addition, the microparticles of the present invention are microparticles containing color nanocomposites rearranged by application of an electric or magnetic field, wherein the microparticles have a pencil hardness of 4 B or less in a dry powder state and a specific surface area using nitrogen gas. In the pore size distribution according to the measurement, the pore volume in the region of 5 nm or less is characterized in that less than 20% of the total pore volume.

In this case, the microparticles are made of a core material including the color nanocomposite and a shell material made of a polymer or a copolymer.

In addition, the color nanocomposite may include nano particles and colorant particles surface-modified with a material containing a reactive group, and a material including nano-particles and reactive groups with a surface modified with a material containing a reactive group. It may contain the colorant particle | grains modified by the surface modification, and may also contain the aggregate of a nanoparticle cluster and a colorant particle.

The preparation method of the microparticles containing the color nanocomposite of the present invention may be an in-situ polymerization using an oil phase / water emulsion, and a coacervation approach. It may also be an interfacial polymerization (interfacial polymerization).

The print media, the printing method, the display element, and the display method of the present invention are characterized by comprising micro particles containing the color nanocomposite.

The color nanocomposite according to the present invention has a very uniform particle distribution and has a large color change by application of an electric or magnetic field, and thus can be applied to various display devices.

In addition, the microparticles using the color nanocomposite have low elasticity and hard properties of the organic polymer constituting the wall material, and unlike the capsules, there is little agglomeration between the particles, and physical phases such as stirring or rotation in the water phase It can be stored for a long time even if it is left without applying force.

In addition, since the microparticles according to the present invention have low shape deformation of the wall material, the micro particles exhibit an effect of performing a printing process such as silk printing, which can be easily mixed with various adhesives and easily coated on a desired substrate.

In addition, the micro-particles according to the present invention can be stored in a powder form by drying at a high temperature, excellent storage stability and ease of storage, excellent visibility (visibility) can be used in various printing, coating process.

In addition, since the stability of the wall structure surrounding the nanocomposite and the uniformity of the particle size ensure the macroscopic uniformity of the color nanocomposite rearranged by application of an electric or magnetic field, the change in color and the vividness of the color to be realized The effect can be further improved.

1 is a conceptual diagram illustrating a color nanocomposite according to various embodiments of the present disclosure.

2 is a process chart showing a method of manufacturing a color nanocomposite according to an embodiment of the present invention.

3 is a process chart showing a method of manufacturing a color nanocomposite according to another embodiment of the present invention.

Figure 4 is a process chart showing a method of manufacturing a color nanocomposite according to another embodiment of the present invention.

5 is a process chart showing a method of manufacturing a color nanocomposite according to another embodiment of the present invention.

6 is a conceptual diagram illustrating a nanocomposite prepared by surface modification.

7 is a conceptual diagram showing a nanocomposite (below) prepared by aggregation.

8 is a conceptual diagram illustrating a manufacturing process of the iron oxide-Prussian blue nanocomposite.

9 shows iron oxide nanoparticles (a), iron oxide-Prussian blue nanocomposites (b) reacted with 16 g of K ₄ Fe (CN) ₆ to 3 g of iron oxide nanoparticles (b), and K ₄ Fe (CN) for 3 g of iron oxide nanoparticles. SEM image of iron oxide-Prussian blue nanocomposite (c) reacted with ₆ 32 g.

10 shows iron oxide nanoparticles (a), iron oxide-Prussian blue nanocomposites (b) reacted with 16 g of K ₄ Fe (CN) ₆ to 3 g of iron oxide nanoparticles (b), and K ₄ Fe (CN) for 3 g of iron oxide nanoparticles. _It is a photograph comparing the powder phase (left) and the water dispersion state (right) of the iron oxide-Prussian blue nanocomposite (c) which reacted ₆ 32 g.

11 is iron oxide nanoparticles (a), and iron oxide nanoparticles for 3g K ₄ Fe (CN) iron oxide was reacted with _{6 16g - K 4 Fe (CN} ) for the Prussian blue nanocomposite (b), iron oxide nanoparticles 3g _{This is} the zeta potential measurement result measured in the state of being dispersed in distilled water of the iron oxide-Prussian blue nanocomposite (c) reacted with ₆ 32g.

12 is a process chart showing the manufacturing process of the microparticles according to an embodiment of the present invention.

It is a particle size distribution graph of the microparticle (a) of an Example and the microparticle (b) of a comparative example.

It is an optical microscope photograph in the emulsion state of the microparticle (a) of an Example, and the microparticle (b) of a comparative example.

15 is an optical microscope photograph of an aqueous phase of the microparticles (a) of the example and the microparticles (b) of the comparative example.

16 is an optical micrograph of the dry powder of the microparticle (a) of the Example and the microparticle (b) of the Comparative Example.

17 is a photograph showing color development when a magnetic field is applied to microparticles.

18 is a spectrum of reflectance change according to the magnetic field strength of the microparticles in powder state.

19 is an optical micrograph of the microparticles (a) of the example and the microparticles (b) of the comparative example after high temperature storage.

20 is a spectrum showing Fourier transform infrared spectroscopy (FT-IR) measurement results for the microparticles of the present invention.

DETAILED DESCRIPTION The following detailed description of the invention refers to the accompanying drawings that show, by way of illustration, specific embodiments in which the invention may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention. It should be understood that the various embodiments of the present invention are different but need not be mutually exclusive. For example, certain shapes, structures, and characteristics described herein may be embodied in other embodiments without departing from the spirit and scope of the invention with respect to one embodiment. In addition, it is to be understood that the location or arrangement of individual components within each disclosed embodiment may be changed without departing from the spirit and scope of the invention. The following detailed description, therefore, is not to be taken in a limiting sense, and the scope of the present invention, if properly described, is defined only by the appended claims, along with the full range of equivalents to which such claims are entitled. In the drawings, like reference numerals refer to the same or similar functions throughout the several aspects, and length, area, thickness, and the like may be exaggerated for convenience.

The color nanocomposite according to an embodiment of the present invention is color-variable by application of an electric or magnetic field, the color difference (ΔE ^* _ab ) before and after application of the electric or magnetic field according to the color coordinates of the CIE color system is 2.2 or more, and the particle size distribution curve The full width at half maximum (FWHM) is characterized in that less than 30nm. In addition, the zeta potential value of the water dispersion state of the color nanocomposite is characterized in that the difference is more than 4 times, preferably 4 to 6 times compared to the water dispersion state of the nanoparticles.

In the present invention, the color difference ΔE ^* _ab indicates the degree of change in color (color caused by reflected light or transmitted light) through the rearrangement or change of charge state of the color nanocomposite before and after application of an electric or magnetic field. By indicating the color difference of 2.2 or more, preferably 3.0 or more, more preferably 3.2 or more as an index, it means that the color change of the degree which can visually clearly confirm the change of color is meant.

In addition, in the present invention, the half width of the particle size distribution curve is an index indicating uniformity of particles, and the half width of the peak is 30 nm or less, preferably 20 nm or less, more preferably around D50 of a single peak measured by particle size analysis. By manufacturing the color nanocomposite having a uniform particle size distribution to be less than 10nm, it is easily rearranged by the application of an electric or magnetic field, it is possible to achieve a uniform color through diffraction or scattering of incident light.

In addition, the zeta potential value of the water dispersion state of the color nanocomposite is characterized in that the difference is more than 4 times, preferably 4 to 6 times compared to the water dispersion state of the nanoparticles. The zeta potential value measured in the water dispersion state tends to be relatively low in the case of nanoparticles, which is directly related to insufficient water dispersion and the lack of arrangement characteristics and color implementation characteristics due to the application of electric or magnetic fields. The color nanocomposite according to the present invention is excellent in water dispersibility and excellent in color change characteristics by application of electric or magnetic fields because the zeta potential value is more than four times higher than that of the nanoparticles. Since the color difference can be achieved, it becomes an index for determining the improved characteristics of the color nanocomposite.

In the present invention, the principle that the color nanocomposite realizes the color may be realized through the intrinsic color of the particles due to the colorant particles contained in the nanocomposite, and at the same time, the nanocomposite may be reapplied by application from the outside of an electric or magnetic field. By arranging or changing the charge state, colors may be realized by transmitting or reflecting light of a specific wavelength.

Therefore, in the present invention, the color nanocomposite should have a very uniform particle size and high mobility in a medium for easy color rearrangement for color realization through rearrangement or change of charge state of particles.

The color nanocomposites of the present invention may be dispersed and present in a medium, or may be dispersed and present in the form of charged particles. In addition, the color nanocomposite may be composed of a core-cell structure or a multi-core-cell structure.

In addition, the color nanocomposite of the present invention exhibits a uniform size in the particle size of 50 to 1000 nm, preferably 100 to 500 nm, more preferably 100 to 300 nm. In addition, when the colorant is included, the uniformity of the particles may be more important than the particle size, and thus may be out of the range of the particle size.

The color nanocomposite of the present invention comprises nanoparticles, wherein the nanoparticles can be conductive particles, metal particles, organometallic particles, metal oxide particles, magnetic particles, hydrophobic organic polymer particles, and by the application of external energy. It may be a particle exhibiting photonic crystal properties imparting regularity to the arrangement and spacing of the particles. For example, silicon (Si), titanium (Ti), barium (Ba), strontium (Sr), iron (Fe), nickel (Ni), cobalt (Co), lead (Pb), aluminum (Al), copper (Cu), silver (Ag), gold (Au), tungsten (W), molybdenum (Mo), zinc (Zn), zirconium (Zr), or any one or more metals or nitrides or oxides thereof. .

In addition, the organic material nanoparticles may be made of a high molecular material such as polystyrene, polyethylene, polypropylene, polyvinyl chloride, polyethylene terephthalate, particles whose surface is modified by an organic compound having a hydrocarbon group, carboxyl group, ester group, ah. Particles whose surface is modified by an organic compound having any one or more of the actual groups, particles whose surface is modified by a complex compound containing a halogen element, and whose surface is modified by a coordination compound containing amines, thiols, and phosphines The particle | grains and particle | grains which form a radical in the surface and have an electric charge are mentioned.

In addition, the nanoparticles may be particles imparting electrical polarization characteristics. That is, as the external magnetic field or electric field is applied to polarize the medium, the polarization of ions or atoms is further induced to increase the amount of polarization, and the residual polarization amount exists even when the external magnetic field or the electric field is not applied and the magnetic or electric field is applied. It can contain ferroelectric materials that remain hysteresis along the direction, and when an external magnetic or electric field is applied, an additional ionic or atomic polarization is induced to increase the amount of polarization greatly, but no external magnetic or electric field is applied. In this case, it may include a paraelectric material and a superparaelectric material in which residual polarization and hysteresis remain.

Such materials may include materials having a perovskite structure. Ie ABO ₃ Examples of the material having a structure include PbZrO ₃ , PbTiO ₃ , Pb (Zr, Ti) O ₃ , SrTiO ₃ , BaTiO ₃ , (Ba, Sr) TiO ₃ , CaTiO ₃ , LiNbO _3, and the like.

In addition, the nanoparticles may be made of particles containing single or different types of metals, oxide particles or photonic crystal particles.

In the case of a metal, a metal nitrate compound, a metal sulfate compound, a metal fluoracetoacetate compound, a metal halide compound, a metal perchloroate compound, a metal sulfamate compound, a metal styrate compound and an organometallic compound Magnetic precursors selected from the group consisting of: alkyl trimethylammonium halide-based cationic ligands, alkyl acids, trialkylphosphines, trialkylphosphine oxides, neutral ligands such as alkylamines, alkylthiols, sodium alkyl sulfates, sodium alkylcarboxylates The amorphous metal gel may be prepared by adding a ligand selected from the group consisting of anionic ligands such as sodium alkyl phosphate, sodium acetate, and the like to a solvent to dissolve it, and heating the phase to crystalline particles.

At this time, the magnetic properties of the particles finally obtained by containing heterogeneous precursors may be enhanced, or various magnetic materials such as superparamagnetism, paramagnetic, ferromagnetic, antiferromagnetic, ferrimagnetic, and diamagnetic may be obtained.

The color nanocomposites of the present invention may be dispersed in a medium and rearranged by application of an electric or magnetic field. Such a medium may be a polar or nonpolar medium. For example, water, methanol, ethanol, propanol, butanol, propylene carbonate, toluene, benzene, hexane, chloroform, halocarbon oil, perchloroethylene, trichloroethylene, isopar-G which is a kind of isoparaffin oil, isopar-M One or more of, isopar-H can be used.

The color nanocomposite of the present invention may have its own intrinsic color and may represent colors by rearrangement of particles, and in addition, various colors may be realized by applying a predetermined color to the medium. In this case, the medium may comprise a dye or a pigment.

The dye may be azo dyes, anthraquinone dyes, carbonium dyes, indigo dyes, sulfide dyes, phthalocyanine dyes, and the like, and the pigments include titanium dioxide, zinc oxide, and lithopone. Zinc sulfonate, Carbon black, Graphite, Chrome yellow, Zinc chromate, Red oxide of iron, Red lead, Cardmium red, Molybdate chrome orange, Royal blue, pressian blue, iron blue, Cobalt blue, Chrome green, Chrome hydroxide, Zinc green Inorganic pigments such as aluminum powder, bronze powder, fluorescent pigment, pearl pigment, or insoluble azo, soluble azo, phthalocyanine, quinacridone, dioxazine, isoindolinone, and dry dye Organic compounds such as phyllocholine, fluorine-based, quinophthalone-based and metal complexes There used to be

Various methods may be applied to the method of manufacturing the color nanocomposite of the present invention. For example, various methods of preparing nanocomposites according to the formation of an emulsion may include various methods as shown in Table 1 below.

Emulsion type	Prize	Characteristic
W / O	Internal award	Colloidal particles
		Colloidal Particle + Hardener
		Colloidal particles + dye
		Colloidal particles + functional substances
	External oil	Emulsifier
	energy	Heat, UV, cooling
O / W	Internal oil	Colloidal particles
		Colloidal Particles + Colorants
		Colloidal Particle + Hardener
		Colloidal Particle + Low Boiling Solvent
		Colloidal particles + functional substances
	External award	Emulsifier
	Size control	Ultrasonic, Nano Nozzle, Spray
	energy	Heat, UV, cooling

That is, as shown in Table 1, a combination of materials included in the inner phase according to the internal water phase / external oil phase (W / O) or the internal oil phase / external water phase (O / W), size control method, energy type, and size The nanocomposite in the form can be prepared.

As an example of various nanocomposites according to the present invention, Figure 1 shows a colored nanocomposite according to various embodiments.

Referring to FIG. 1, the nanocomposite of the present invention may be formed by mixing colloidal particles and dyes or pigments (FIG. 1A), and may further include an expression material to form nanocomposites (FIG. 1B), and a cured material. The nanocomposite may be additionally included (FIG. 1C), or the nanocomposite may be formed additionally including a hardening material and an expression material (FIG. 1D).

Referring to the specific method for producing a nanocomposite as described above in the present invention through some examples as follows.

2 is a process chart showing a method of manufacturing a color nanocomposite according to an embodiment of the present invention.

In the present embodiment, the nanocomposite comprises the steps of preparing a mixture by mixing the colorant particles and nanoparticles; Mixing a hydrophobic material in the mixture to form a miniemulsion; And polymerizing the miniemulsion and a monomer.

In this case, in order to form a miniemulsion, an anionic surfactant, a cationic surfactant, or a nonionic surfactant is included to maintain the dispersion of the colloidal particles. In addition, the emulsion may be prepared by a chemical method using interfacial chemical properties or by physical methods such as ultrasonic dispersion, rotary stirring, colloid mill, homogenizer and the like.

In this case, the step of polymerization may be carried out by adding a droplet of the miniemulsion to the medium, after preparing a suspension of the hydrophobic material and the colorant particles, it may be carried out by adding an initiator.

In addition, the monomers applied to the miniemulsion of the present invention are styrene, pyridine, pyrrole, aniline, pyrrolidone, acrylic acid, urethane, Thiophene, carbazole, fluorene, fluorene, vinyl alcohol, vinyl alcohol, vinyl glycol, ethylene glycol, ethoxy acrylate may be one or more.

3 is a process chart showing a method of manufacturing a color nanocomposite according to another embodiment of the present invention.

In the manufacturing method, the nanocomposite comprises the steps of preparing a nanoparticle surface-modified (을) the surface of the nanoparticles with a material containing a reactive group; Preparing a dispersion by mixing the surface-modified nanoparticles and colorant particles; It can be prepared, including; the surface-modified nanoparticles and the adsorption reaction of the colorant particles.

The surface modification is to make the surface of the nanoparticles with a reactive group such as a hydroxyl group (-OH), an amine group (-NH), etc., for example, by coating the nanoparticles with a silica containing a hydroxyl group which is a reactive group may cause surface modification. have. It can also be modified with an amine group (-NH) through the coating of aminosilane.

The type of surface group depends on the type of colorant to be adsorbed. For example, when the carbon nanoparticles are used as the colorant, the surface is replaced with a hydroxyl group and adsorbed. When dye particles such as methylene blue are used as the colorant, the surface may be replaced with an amine group.

When the carbon nanoparticles are adsorbed, graphene oxide grafted with ethylene diamine may be used instead of the carbon nanoparticles, or carbon nanoparticles modified with a hydroxyl group may be used to increase the adsorption reaction efficiency.

In another embodiment of the present invention it is possible to cause the adsorption reaction through the surface modification of the colorant as described above.

Figure 4 is a process chart showing a method of manufacturing a color nanocomposite according to another embodiment of the present invention.

According to Figure 4, the color nanocomposite is a step of modifying the surface of the colorant particles; Preparing a dispersion by mixing the colorant particles and the nanoparticles; It is prepared, including; causing the adsorption reaction of the colorant particles and nanoparticles.

For example, 5% of graphene oxide is mixed with ethanol and then dispersed with an ultrasonic disperser for 2 hours, and the dispersion is placed in a reactor and adjusted to pH 11 with ammonia while stirring. Then, aminosilane is added to convert the surface of graphene oxide into an amine group. After washing this, mixed with silica-coated iron oxide nanoparticle cluster colloid aqueous solution, the temperature was raised to 80 ° C. and stirred for 12 hours to generate an adsorption reaction, and the zeta potential of -45 mV to -50 mV had a positive value or a negative value. It can be confirmed that adsorption is good even if the charge is very low.

In addition, when preparing a nanocomposite of 150nm class, 10 to 30nm class carbon black particles may be acid treated to modify the surface with a hydroxyl group and then react with the iron oxide nanoparticle cluster colloid modified with an amine group.

As another example, the nanocomposite may be prepared by using an iron oxide nanoparticle cluster coated with silica and surface modified with a hydroxyl group and methylene blue modified with an amine group.

That is, the dispersed iron oxide nanoparticle cluster colloid is adjusted to pH 11 using ammonia, mixed with an ethanol solution in which 1% methylene blue is dissolved, and stirred for 12 hours to prepare a nanocomposite, and the zeta potential value is -7 to Measured at +10 mV. This can be confirmed that the reaction occurs firmly compared with the zeta potential value of -48 to -35mV of the general iron oxide nanoparticle cluster coated with silica.

In this case, it was confirmed that the surface color of the particles was changed from brown to dark navy blue to black to prepare a nanocomposite having an intrinsic color.

5 is a process chart showing a method of manufacturing a color nanocomposite according to another embodiment of the present invention.

According to FIG. 5, the color nanocomposite may include mixing nanoparticle clusters and colorant particles; And agglomeration reaction of the nanoparticle clusters and the colorant particles.

In this case, since two kinds of particles are mixed to form a nanocomposite, interparticle mixing and dispersion are very important factors. Therefore, the nanoparticle cluster and the colorant particles should satisfy a range of 5 nm or less in the difference between the median particle diameter (ΔD50) and the average particle diameter (ΔDm) according to the particle size distribution curve.

If the particle size distribution curve is symmetric about D50, there is no difference between D50 and Dm.However, if the particle size distribution curve is asymmetric, the difference between D50 and Dm occurs.The larger the difference, the less uniform the particle size distribution is. Means that.

That is, ΔD50 is an index indicating the size of two kinds of particles, and when 5 nm or less, two kinds of particles may be uniformly mixed to substantially the same size to form a nanocomposite. In addition, ΔDm is an index indicating particle uniformity and particle size difference between two kinds of particles, and simultaneously satisfies a value of 5 nm or less of ΔD50 and ΔDm, so that the particle size is uniform and the particle size difference is substantially the same. It will be used as an indicator.

For example, when the nanocomposite is prepared by oxidizing the surface of 20 to 50nm grade carbon black, surface modification with a hydroxyl group to be easily dispersed in an ethylene glycol solvent, and then mixed with iron oxide nanoparticle clusters. As the concentration was increased, the color of the surface was changed to black, and it was confirmed that the color can be adjusted according to the ratio of mixing two kinds of particles.

In the present invention, the difference between the manufacturing method by the surface modification and the manufacturing method by the aggregation will form a nanocomposite prepared by the surface modification (FIG. 6) and a nanocomposite prepared by the aggregation (FIG. 7).

Referring to FIG. 6, in the manufacturing method based on surface modification, a negative (−) charge is applied to a surface by coating a material (eg, silica) capable of imparting a reactor to the surface of the nanoparticles (2), By reacting with the amine group (1) of methylene blue having a positive charge, the dye particles are physically adsorbed or chemisorbed on the surface of the nanoparticles to form nanocomposites (3).

Referring to FIG. 7, in the case of the manufacturing method by flocculation, the nanoparticles 1 and the oxidized carbon black particles 2 are dispersed in an ethylene glycol solvent and then flocculated (3) under oil / water phase conditions. Nanocomposites are formed. In this case, since the intrinsic color of the nanocomposite changes depending on the amount of carbon black mixed, the color can be adjusted according to the use.

In all manufacturing methods applied to the present invention, the colorant particles may be any one or more of dye particles, pigment particles, surface-modified carbon nanoparticles, graphite, surface-modified graphene oxide particles.

In this case, the dye particles are particles consisting of any one or more of azo dyes, anthraquinone dyes, carbonium dyes, indigo dyes, sulfide dyes, phthalocyanine dyes, the pigment particles are pigments titanium oxide (titanium dioxide), Zinc oxide, lithopon, zinc sulfonate, chrome yellow, zinc chromate, red oxide of iron, red lead, cadmium ( cardmium red, molybdate chrome orange, milori blue, pressian blue, iron blue, cobalt blue, chrome green, chrome hydroxide, zinc green ), Silver powder, bronze powder, fluorescent pigment, pearl pigment or any one or more of inorganic pigments, or insoluble azo, soluble azo, phthalocyanine, quinacridone, dioxazine, isoindoli Paddy field, vat dye system, phylcholine series, fluorine System, it may be a quinophthalone-based, any of metal complexes or more organic pigments.

In Example, the iron oxide-Prussian blue nanocomposite was prepared.

100 g of distilled water was added to a 300 ml double jacket reactor, and ₃ g of Fe ₃ O ₄ iron oxide nanoparticles having a particle diameter of 200 nm were added, followed by dispersion for 2 hours through an ultrasonic sprayer. After dispersion, a stir bar was installed and the double jacketed reactor was sealed. In the reactor in which the iron oxide nanoparticles were dispersed, K ₄ Fe (CN) _{6, which} is a precursor of Prussian blue, was added to the aqueous solution and stirred at 350 rpm for 10 minutes.

1N-HCl solution was used to titrate pH 2 to the mixed dispersion solution prepared through the above procedure, and stirred vigorously at 500 rpm for 1 hour.

When the HCl solution is titrated, iron ions are formed on the surface of the iron oxide nanoparticles as shown in FIG. 8, and when K ₄ Fe (CN) ₆ is added thereto, a surface reaction occurs to cause the K ₄ Fe (CN) ₆ iron oxide particles. Coating on the surface of the nanocomposite will be formed.

After stirring for 1 hour, the color of the dispersion solution was found to turn dark blue or ultra blue. In this state, since the Prussian blue is coated on the surface of the iron oxide nanoparticles, the stirring is terminated.

The prepared turquoise dispersion solution was washed five times with distilled water while applying a magnetic field using a permanent magnet, and then dried in an oven at 70 ° C. to obtain a turquoise powder.

SEM observation of the prepared nanocomposite is shown in FIG. 9.

Referring to the results of FIG. 9, it can be seen that the Prussian blue is coated on the surface by increasing the particle size in the iron oxide-Prussian blue nanocomposite when compared to the iron oxide nanoparticles (a). In addition, when the content of K ₄ Fe (CN) ₆ is increased, the surface roughness of the particles tends to increase, indicating that it is necessary to react the nanoparticles with the pigment at an appropriate ratio depending on the type of nanoparticles or pigments. .

In addition, when contrasting the 200 nm iron oxide nanoparticles and the two iron oxide-Prussian blue nanocomposites, it can be seen that the color on the powder is reproduced as it is in the state of dispersion (Fig. 10).

In addition, when the iron oxide nanoparticles and the iron oxide-prussian blue nanocomposite are respectively dispersed in distilled water and the zeta potential of the iron oxide nanoparticles is measured, the zeta potential value of the iron oxide nanoparticles is relatively low as 8 mV. In the case of the composite, the dispersion state was very stable at 35 to 40 mV (FIG. 11).

These results suggest that the iron oxide-Prussian blue nanocomposite of the present invention exhibits excellent properties as photonic crystals under magnetic field application conditions. In addition, a high zeta potential value may result in the nanocomposite of the present invention exhibiting a distinct color change by application of an electric or magnetic field.

In particular, since the zeta potential value of the nanocomposite is 4 to 5 times different compared to the nanoparticles in a dispersed state, the rearrangement characteristics of the nanocomposite are greatly improved by applying electric or magnetic fields. Can be.

The color nanocomposite of the present invention can be applied to various fields such as color variable glass, color variable wallpaper, color variable solar cell, color variable sensor, color variable paper, color variable ink, anti-counterfeiting tag, and the like by applying to a labeling device.

For example, when applied as a composite anti-counterfeiting film, applying a magnetic field by applying a color nanocomposite of the present invention comprising a display area formed on a surface of a substrate or a corresponding object, and dispersed in a curing medium to the display area At least one of the reflected light and the transmittance is changed, and when a specific energy is applied, an expression material expressing predetermined characteristics may be separately present in the curing medium.

You can also use these films to make alcoholic beverages, gourmet foods, bills, checks, ID cards, passports, vehicle production numbers, high-end machine IDs, high-end merchandise labels, clothing labels, high-end bags labels, software product markings, high-end electronic product numbers. It can be applied as a composite anti-counterfeiting technique.

Next, the microparticles of the present invention are microparticles containing color nanocomposites that are rearranged by application of an electric or magnetic field, wherein the microparticles have a pencil hardness of 4B or less, and the pores according to specific surface area measurement using nitrogen gas. It is characterized in that the pore volume in the region of 5 nm or less in the pore size distribution is 20% or less of the total pore volume. In addition, the zeta potential value of the water dispersion state of the color nanocomposite is characterized in that the difference is more than 4 times, preferably 4 to 6 times compared to the water dispersion state of the nanoparticles.

The microparticles of the present invention have lower elasticity and harder properties of wall materials than conventional capsules. Therefore, it is excellent in the storage of the color nanocomposite contained in the particles, unlike the capsule is easy to print because the particles are not destroyed during printing. The colored nanocomposite exhibiting these properties exhibits a pencil hardness of 4 B or less, preferably 3 B or less, in a dry powder state. On the other hand, considering that the conventional microcapsule has a pencil hardness of 9B or more and the strength of the wall material is very weak, it can be seen that the microparticles of the present invention greatly improve the wall material strength.

The strength of the wall material of such microparticles can be inferred from the void volume of the micropores present in the wall material. Pore volume can be measured by BET specific surface area measurement using gas adsorption-desorption method. In this case, the surface area is measured by adsorption-desorption of gases such as nitrogen, argon, krypton, oxygen, helium and carbon monoxide.

The micropores are pores of 5 nm or less, and the higher the density of the polymer constituting the wall material, the smaller the pore volume of the micropores. Therefore, the pore volume of the micropore region tends to be inversely proportional to the strength of the wall material, and in order to obtain sufficient strength of the microcapsules in the present invention, the pore volume in the region of 5 nm or less must satisfy 20% or less of the total pore volume. When the pore volume in the 5 nm or less region exceeds 20% of the total pore volume, the wall is observed to be formed of an aggregate of polymers, which is associated with a tendency to decrease the volume of the micropore region.

As illustrated in FIG. 12, the microparticles according to the present invention may be prepared through a reaction process of forming an emulsion and core-cell structuring.

First, the core material is prepared by dispersing the color nanocomposite in a dispersion medium (S110). In this case, the color nanocomposite may be dispersed at a ratio of 0.1 to 25% by weight based on the dispersion medium, but may be dispersed in a larger amount as needed. The dispersion of the shim material is dispersed using an ultrasonic disperser or homogenizer.

Next, by mixing the polymer to form the wall material of the microparticles to prepare a prepolymer by acidity control (S120). This process can be performed simultaneously with the process of preparing a dispersion of the color nanocomposites.

As the polymer for forming the wall material, a polymer precursor capable of exhibiting low elasticity and rigid properties may be used. A copolymer such as urea-formaldehyde, melamine-formaldehyde, methylvinyl ether commaleic anhydride, gelatin, polyvinyl Polymers such as alcohol, polyvinylacetate, cellulosic derivatives, acacia, carrageenan, carboxymethylcellulose, hydrolyzed styrene anhydride copolymers, agar, alginate, casein, albumin, cellulose phthalate and the like can be used. By controlling the hydrophilicity and hydrophobicity of such a polymer it is possible to form a wall surrounding the nanocomposite. In addition, the prepolymer may be prepared in a dispersion by dispersing in a dispersion medium like the nanocomposite.

The dispersion of the nanocomposite prepared in step S110 and the prepolymer dispersion of the wall material prepared in step S120 may be mixed and stirred to form an emulsion (S130). It is necessary to optimize the ratio of the nanocomposite and the prepolymer under the conditions for forming such an emulsion, and the two dispersions may be mixed in a volume ratio of 1: 5 to 1:12. In addition, a stabilizer may be added to improve dispersibility. In the emulsion, the color nanocomposite may be in a dispersed phase and the wall material may be in a continuous phase.

In step S130, an additive may be added to increase the stability of the emulsion. Such additives may be organic polymers having high viscosity and high wettability after dissolution in an aqueous phase. Specifically, gelatin, polyvinyl alcohol, sodium carboxymethyl cellulose, starch, hydroxyethyl cellulose, polyvinylpyrrolidone, alginate At least one of them can be used.

The core material dispersion may be encapsulated by controlling the pH and temperature of the emulsion formed in the step S130 so that the continuous wall material dispersion is deposited around the discolored magnetic discoloring ink to form a wall of the capsule (S140). That is, the encapsulation is performed by an in situ polymerization method, in which case, the capsule wall material may be more densely formed to reduce the elasticity, thereby adding an additive to increase the hardness of the wall material.

The type of additive to be added may be an ionic or polar substance that is well soluble in the aqueous phase. For example, at least one of ammonium chloride, resorcinol, hydroquinone, and catechol, which is a curing catalyst, may be used.

The microparticles containing the color nanocomposite of the present invention may be prepared by the in situ polymerization method as described above, but may also be prepared by a coacervation method E or an interfacial polymerization method.

In the case of the coacervation method, an oil phase / water emulsion of an internal phase and an external phase is used. The color nanocomposite colloid is coacervated out from the aqueous outer phase and granulated by forming walls in the oil phase droplets of the inner phase by controlling temperature, pH, relative concentration, and the like. In the case of coacervation, urea-formaldehyde, melamine-formaldehyde, gelatin, arabic rubber, or the like can be used as the wall material.

In the case of the interfacial polymerization method, depending on the presence of the lipophilic monomer in the inner phase, it is present as an emulsion in the aqueous outer phase. The monomer in the inner phase liquid crystal reacts with the monomer introduced into the aqueous outer phase, the polymerization takes place at the interface between the droplet of the inner phase and the surrounding aqueous outer phase, and a wall of particles is formed around the droplet. The formed wall is relatively thin and permeable, but unlike other manufacturing methods, heating is not required, and thus there is an advantage in that various dielectric liquids can be applied.

The microparticles according to the invention consist of a uniform sphere of 10 to 100 μm, preferably 10 to 50 μm, more preferably 10 to 40 μm. The uniformity of the shape and size of the capsule is to ensure the macroscopic uniformity of the color nanocomposite rearranged by the electric or magnetic field, thereby improving the color change and the sharpness of the color to be implemented. If the uniformity of the shape and size of the microparticles is not secured, even if the color nanocomposites dispersed in the microparticles are rearranged uniformly, irregularities are increased macroscopically, resulting in insufficient color change and implementation.

Table 2 shows the results of measuring the particle size distribution of the microparticles (Comparative Example) prepared by reducing the amount of the curing catalyst to 1/2 without using the microparticles (Example) and the stabilizer prepared by the present invention. have.

	D [4,3] (µm)	D (ν, 0.1) (μm)	D (ν, 0.5) (μm)	D (ν, 0.9) (μm)
Example	23.58	12.99	23.23	35.67
Comparative example	113.95	23.08	104.53	216.64

Looking at Table 2, the microparticles according to the present invention has a D50 of 23.23 ㎛ having the size of the particle required by the present invention, it can be seen that the D50 is rapidly increased when the manufacturing conditions are changed. Uniformity of the particle size distribution can also be seen by examining the particle size distribution graph of the microparticles according to Examples and Comparative Examples (Fig. 13).

Also in D [4,3], the comparative example is 113.95 µm, which shows that the uniformity of the average particle size distribution is greatly deteriorated compared to the examples. Therefore, it was confirmed that the microparticles of the present invention can be obtained by strictly controlling the production conditions and physical properties of the microparticles in the present invention.

Even when looking at the optical micrographs of the emulsion state and the state in the water phase (Fig. 15) of the microparticles of the above-described Example (Fig. 14A) and the Comparative Example (Fig. 14B), which partially changed the manufacturing conditions, the manufacturing conditions were partially changed. When the present invention can be confirmed that the desired shape and particle size uniformity can not be secured.

The microparticles of the present invention have less agglomeration between the particles even after drying due to the low elasticity of the wall material and the hard properties. This can be seen by examining the optical micrograph of the powder state prepared by the room temperature drying of the Example (FIG. 16A) and the Comparative Example (FIG. 16B). In Example, no agglomeration occurred after drying and almost no change in the shape of the particles was observed, but in the Comparative Example, it was confirmed that the shape change and the partial agglomeration occurred. Therefore, the particles according to the comparative example can be seen to exhibit properties similar to the conventional capsule.

FIG. 17 is a photograph showing the appearance of color when a rubber particle having a magnetic field strength of 100 gauss is applied to the rear surface of the slide glass after applying the microparticles of the present invention to the slide glass at a thickness of 100 μm. The uniformity of the microparticles of the present invention has the effect of causing a noticeable color change even in a weak magnetic field.

18 shows the reflectance according to the magnetic field strength by making the microparticles of the present invention into a powder state. It can be seen that when the magnetic field strength increases in the direction of the arrow, the reflection peak moves at a low wavelength in the direction of the arrow. Therefore, the phenomenon of color change according to the magnetic intensity can be confirmed through spectroscopic data.

The microparticles of the present invention exhibit excellent heat resistance due to the low elasticity and rigid properties of the wall material. Referring to Figure 19, the microparticles according to the Examples and Comparative Examples evenly sprayed on the slide glass and left for 24 hours in a hot air dryer at 100 ℃, the result of the change in the shape of the particles observed. From the above results, it was confirmed that the rigidity of the wall material of the microparticles according to the present invention is excellent in thermal stability.

This property means that it can withstand high temperature printing conditions, which means that it can be applied to various types of display elements or print media.

In addition, Fourier transform infrared spectroscopy (FT-IR) measurement results of the microcapsules in which the wall material was formed of urea-formaldehyde are shown in FIG. 20. Looking at the FT-IR spectrum, it is 1041㎝ ^-1 was observed for the 1097㎝ ^-1 and NCN stretching corresponding to CN stretch was confirmed that the wall material has been configured correctly by the polymer.

In addition, as a result of measuring the pencil hardness of the microparticles according to the Examples and Comparative Examples, it was confirmed that the strength of the wall material of the microparticles of the present invention was very improved by obtaining the measurement results of 3B in the Examples and 9B in the Comparative Examples.

From the measurement results of the pencil hardness and the pore volume ratio of the micropore region, the wall material of the microparticles of the present invention was found to have a very dense structure, a very high elasticity, a low elasticity, and a hard property.

The microparticles including the color nanocomposite of the present invention have no agglomeration during dry storage, and are excellent in thermal stability and wall strength, and thus can be applied to various types of printing, and particularly heat resistance and coagulation resistance such as silk screen printing are required. It can be applied to inks that can be used to broaden the application.

When the microparticles according to the present invention are applied to an ink for printing, they can be dispersed and used in binders such as water-soluble polymers, water-dispersible polymers, oil-soluble polymers, thermosetting polymers, thermoplastic polymers, UV curable polymers, radiation curable polymers, and the like. The surface active agent and the crosslinking agent may be added to the binder to improve the durability of the printing or coating process.

Printing using the microparticles includes all forms of printing and coating, and may be a coating such as roll coating, gravure coating, dip coating, spray coating, meniscus coating, sping coating, brush coating, air knife coating, or silkscreen. It may be carried out through printing such as printing, electrostatic printing, thermal printing, inkjet printing.

For example, complex counterfeits such as alcoholic beverages, gourmet foods, bills, checks, identification cards, passports, vehicle production numbers, high-end machine IDs, high-end merchandise labels, clothing labels, high-end bags labels, software product markings, high-end electronic product numbers, etc. It can be produced with a printing medium such as an ink for the prevention technology, it can be printed on a variety of products using such a printing medium.

In addition, the display device may be manufactured with various display devices such as color variable glass, color variable wallpaper, color variable solar cell, color variable sensor, color variable paper, color variable ink, and anti-counterfeiting tag, and display colors using such display elements. You can do it. In the method of displaying color, various colors can be displayed by using a medium generating a magnetic or electric field to cause a color change, to maintain a changed color, or to return to the original color when the magnetic or electric field is removed.

In addition, it may be used as a color display device for forming pixels by forming barrier ribs using a roll-to-roll method and injecting a display material including the microparticles of the present invention.

In addition, two or more kinds of microparticles having different thresholds for electric fields may be applied to the reflective display device. That is, the microparticles having different colors may be positioned in the reflective display device divided into the partition including the upper and lower substrates and the upper and lower electrodes, thereby realizing various colors by applying an electric field.

Moreover, it can also manufacture into a film by apply | coating and hardening the solution containing the microparticle of this invention on a light transmissive film.

Although the present invention has been shown and described with reference to preferred embodiments as described above, it is not limited to the above embodiments and various modifications made by those skilled in the art without departing from the spirit of the present invention. Modifications and variations are possible. Such modifications and variations are intended to fall within the scope of the invention and the appended claims.

Claims (31)

1. A color nanocomposite comprising nanoparticles rearranged by application of an electric or magnetic field,

   The color nanocomposite has a color difference (ΔE ^* _ab ) of 2.2 or more before and after application of an electric or magnetic field according to the color coordinates of the CIE color system, and a full width at half maximum (FWHM) of the particle size distribution curve is 30 nm or less. Colored nanocomposites.
2. The method according to claim 1,

   The color nanocomposite may be dispersed in a polar or nonpolar medium and rearranged by application of an electric or magnetic field.
3. The method according to claim 2,

   The medium is colored nanocomposite, characterized in that it comprises a dye or pigment.
4. The method according to claim 1,

   The color nanocomposite is a color nanocomposite, characterized in that the mixture of the colorant particles and nanoparticles coated with a hydrophobic material.
5. The method according to claim 1,

   The color nanocomposite is a color nanocomposite, characterized in that consisting of nanoparticles coated with a colorant.
6. The method according to claim 1,

   The color nanocomposite is a color nanocomposite, characterized in that the particles formed by the aggregation of the colorant particles and nanoparticles.
7. The method according to claim 4 to 6,

   The nanoparticles are silicon (Si), titanium (Ti), barium (Ba), strontium (Sr), iron (Fe), nickel (Ni), cobalt (Co), lead (Pb), aluminum (Al), copper (Cu), silver (Ag), gold (Au), tungsten (W), molybdenum (Mo), zinc (Zn), zirconium (Zr), or any one or more metals or nitrides or oxides thereof Color nanocomposites.
8. The method according to claim 4 to 6,

   The colorant particles may be any one or more of dye particles, pigment particles, surface-modified carbon nanoparticles, graphite, and surface-modified graphene oxide particles.
9. As a method of manufacturing the colored nanocomposite of claim 1,

   Preparing a mixture by mixing the colorant particles and the nanoparticles;

   Mixing a hydrophobic material in the mixture to form a miniemulsion;

   Polymerizing the miniemulsion and a monomer;

   Method for producing a color nanocomposite comprising a.
10. As a method of manufacturing the colored nanocomposite of claim 1,

    Preparing nanoparticles whose surface is modified by a material containing a reactive group;

    Preparing a dispersion by mixing the surface-modified nanoparticles and colorant particles;

    Causing adsorption reaction of the surface modified nanoparticles and the colorant particles;

    Method for producing a color nanocomposite comprising a.
11. As a method of manufacturing the colored nanocomposite of claim 1,

    Modifying the surface of the nanoparticles;

    Modifying the surface of the colorant particles;

    Preparing a dispersion by mixing the colorant particles and the nanoparticles;

    Causing adsorption reaction of the colorant particles and the nanoparticles;

    Method for producing a color nanocomposite comprising a.
12. As a method of manufacturing the colored nanocomposite of claim 1,

    Mixing the nanoparticle clusters and the colorant particles;

    Causing an aggregation reaction of the nanoparticle clusters and the colorant particles;

    Method for producing a color nanocomposite comprising a.
13. The method according to any one of claims 9 to 12,

    The nanoparticles are silicon (Si), titanium (Ti), barium (Ba), strontium (Sr), iron (Fe), nickel (Ni), cobalt (Co), lead (Pb), aluminum (Al), copper (Cu), silver (Ag), gold (Au), tungsten (W), molybdenum (Mo), zinc (Zn), zirconium (Zr), or any one or more metals or nitrides or oxides thereof Method for producing a color nanocomposite.
14. The method according to any one of claims 9 to 12,

    The colorant particles are any one or more of dye particles, pigment particles, surface-modified carbon nanoparticles, graphite, surface-modified graphene oxide particles or more or more.
15. The method according to claim 14,

    The dye particles are particles consisting of any one or more of azo dyes, anthraquinone dyes, carbonium dyes, indigo dyes, sulfide dyes, and phthalocyanine dyes, and the pigment particles are titanium oxide (titanium dioxide) or zinc oxide. zinc oxide, lithopon, zinc sulfonate, chrome yellow, zinc chromate, red oxide of iron, red lead, cadmium red ), Molybdate chrome orange, blue blue, pressian blue, iron blue, cobalt blue, chrome green, chromium hydroxide, zinc green, Inorganic pigments of any one or more of silver powder, bronze powder, fluorescent pigment, pearl pigment, or insoluble azo, soluble azo, phthalocyanine, quinacridone, dioxazine, isoindolinone, Vat dyes, phylcholine, fluorine, Smirnoff etalon-based method of producing a color nanocomposite according to any one or more of the organic pigment characterized in that the metal of the complex.
16. The method according to claim 9,

    The monomers include styrene, pyridine, pyrrole, aniline, pyrrolidone, pyrrolidone, acrylic acid, urethane, thiophene, and carbazole. ), Fluorene (fluorene), vinyl alcohol (vinylalcohol), ethylene glycol (ethylene glycol), ethoxy acrylate (ethoxy acrylate) any one or more of the manufacturing method of the color nanocomposite.
17. The method according to claim 9,

    Wherein the step of polymerization is a method of producing a color nanocomposite, characterized in that by performing the droplets of the mini-emulsion to the medium.
18. The method according to claim 9,

    The polymerizing step is prepared by producing a suspension of the hydrophobic material and the colorant particles, the method of producing a color nanocomposite, characterized in that by adding an initiator.
19. The method according to claim 12,

    The nanoparticle cluster and the colorant particles are a method of producing a color nanocomposite, characterized in that the difference between the median particle size (ΔD50) and the average particle diameter (ΔDm) according to the particle size distribution curve is 5nm or less.
20. As microparticles containing the color nanocomposite of Claim 1,

    The microparticles have a pencil hardness of 4 B or less in a dry powder state, and a pore volume of 5 nm or less in a pore size distribution according to a specific surface area measurement using nitrogen gas is 20% of the total pore volume. Micro particles containing colored nanocomposites, characterized in that the% or less.
21. The method of claim 20,

    The microparticles are microparticles containing the color nanocomposite, characterized in that the core material comprising the color nanocomposite and the shell material made of a polymer.
22. The method of claim 20,

    The color nanocomposite is a micro-particle containing a color nanocomposite, characterized in that it comprises a nanoparticles and colorant particles surface-modified with a material containing a reactive group.
23. The method of claim 20,

    The color nanocomposite includes nanoparticles surface-modified with a material containing a reactive group and colorant particles surface-modified with a material containing a reactive group.
24. The method of claim 20,

    The colored nanocomposite comprises nanoparticle clusters and aggregates of colorant particles, wherein the microparticles containing the colored nanocomposite.
25. A method for producing microparticles containing a color nanocomposite according to claim 20, wherein the method is an in-situ polymerization method using an oil phase / water emulsion (O / W emulsion). Method for producing microparticles containing nanocomposites.
26. The method for producing microparticles containing the color nanocomposites according to claim 20, wherein the production method is a coacervation approach.
27. The method for producing microparticles containing the color nanocomposite according to claim 20, wherein the production method is an interfacial polymerization.
28. A print media comprising microparticles containing the color nanocomposites according to claim 20.
29. A printing method using a printing medium according to claim 28.
30. A display device comprising the microparticles containing the color nanocomposite according to claim 20.
31. A display method using the display element according to claim 30.

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