KR101339080B1 - Magnetic Particle and the Fabrication Method Thereof - Google Patents

Magnetic Particle and the Fabrication Method Thereof Download PDF

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KR101339080B1
KR101339080B1 KR1020100139152A KR20100139152A KR101339080B1 KR 101339080 B1 KR101339080 B1 KR 101339080B1 KR 1020100139152 A KR1020100139152 A KR 1020100139152A KR 20100139152 A KR20100139152 A KR 20100139152A KR 101339080 B1 KR101339080 B1 KR 101339080B1
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shell
magnetic
forming
particles
magnetic particles
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KR1020100139152A
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Korean (ko)
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KR20120077258A (en
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최원균
김동후
김수동
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한국조폐공사
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Abstract

The present invention relates to a magnetic particle and a method for producing the same, and more particularly, comprising a magnetic core and a shell, and comprising a continuous or discontinuous void formed between or between the core and the shell, wherein the gap or diameter of the void is at least 10 nm; The present invention relates to a magnetic particle including an inorganic light emitting layer and a method of manufacturing the same, which may have not only basic magnetic properties but also light emission characteristics of absorbing / emitting light in a specific region, and thus may have anti-counterfeiting use with strong security. It has high brightness, controlled specific gravity, and color is controlled differently from the color of the dark magnetic material itself, and has the advantage of high oil absorption and large surface area, which is color ink, general paint, automotive powder It can be used in pigments, cosmetic pigments, catalyst paints, in particular, it is used as a security ink of oil certificates, there is an advantage that can conceal the area and shape to which the security particles are applied.

Description

Magnetic Particles and the Fabrication Method Thereof

The present invention relates to magnetic particles, and more particularly, to a magnetic particle comprising a shell including a void portion on a magnetic core and comprising an inorganic light emitting layer and a method of manufacturing the same.

The main application fields of magnetic powder are information such as permanent magnet whose main purpose is to provide magnetic flux, various magnetic sensors that infer the change of external physical quantity by reading the characteristic change of magnetic body according to the change of external magnetic field, and hard disk And a storage device for storing the same. In the field of anti-counterfeiting, it is generally included in a product for panning the change of characteristics of the magnetic material. However, since the general magnetic powder has a color of dark gray or dark brown, its application is limited in applications requiring bright colors, and there is a disadvantage in that the anti-counterfeiting effect is insufficient only by magnetic properties. Therefore, in order to solve this problem, bright magnetic materials using core-shell technology have been developed. Through this, it is used for various purposes such as color inks, general paints, automotive powder pigments, cosmetic pigments, catalyst paints, and anti-counterfeiting inks by giving the magnetic particles the characteristics of vivid color and high brightness.

Therefore, there has been a market demand for a magnetic material having a variety of specialized colors used for such various uses, and various studies are being conducted on techniques for concealing dark colors of the magnetic material.

As a conventional technique of concealing the dark color of the magnetic material, a white powder and a manufacturing method thereof (Korean Patent Laid-Open Publication No. 10-2006-0028393) provide a method of manufacturing a bright magnetic body using a titanium oxide film and a silver film.

However, in order to use magnetic materials in various fields such as inks, paints, biomaterials, and catalysts, magnetic materials having high oil absorption and high specific surface area are required, as well as brightness and color, specific gravity is adjusted according to the use. It also needs to be supplemented for use in anti-counterfeiting technologies that require more complex and special functions.

The present invention not only has magnetic properties, but also has luminescent properties to absorb / emit light in a specific area, thereby having strong security, very high brightness, controlled color and specific gravity, high oil absorption and high specific surface area. To provide a magnetic particle and a method of manufacturing the same, and also in an exemplary embodiment of the present invention security ink that can effectively conceal the area and shape of the security particle is applied to prevent forgery and tampering of the oil price certificate To provide.

In one embodiment of the present invention comprising a magnetic core and a shell, comprising a continuous or discontinuous void formed between the core and the shell or in the shell, wherein the gap or diameter of the void is at least 10 nm; It provides a magnetic particle comprising an inorganic light emitting layer.

In the above and the following description, the "inorganic light emitting layer" may be defined as a layer including a light emitting material using a host-guest material.

In the inorganic light emitting layer, Erbium, Europium, Ytterbium, Holmium, Thulium, and the like may be used as the guest material of the material forming the shell. It can be freely changed according to the light emitting area. Yttrium, Gadolinium, Vanadium, Zinc, Titanium, and their oxidizing compounds may be used as host materials for the shell-forming materials that may be used. The material capable of transferring electrons to the guest material is not particularly limited. In other words, the inorganic light emitting layer is selected from the group consisting of at least one host material selected from the group consisting of erbium, europium, ytterbium, holium, and thulium, and the group consisting of yttrium, gadolinium, vanadium, zinc, titanium, and oxides thereof Compound having a host: guest combination consisting of at least one guest.

For example, the light emitting layer may include a compound having a host: guest combination of YVO 4 : Eu, YVO 4 : Er, YVO 4 : Nd, YVO 4 : Ho, and YVO 4 : Tm. Due to the nature of the present invention in which the shell uniformly surrounds the core, the polymer structure generating agent may be variously changed according to the purpose.

The kind of the polymer constructing agent that can be used is not particularly limited, and polyethylene glycol is preferred in the present invention.

The shell material of the core / shell nanoparticles produced by the sol-gel reaction improves the luminescence properties when the crystallinity is improved in the heat treatment process after drying, and the heat treatment temperature can be varied in order to control the luminescence properties according to the purpose. have.

The prepared core / shell nanoparticles are very stable at room temperature and atmospheric pressure and can be safely stored in air for several months. Moreover, depending on the shell material, absorbing light in a specific area immediately emits light in that particular area. At this time, the emitted light can be detected by the photoluminescence detector to measure the emission characteristics.

In the magnetic particles according to an embodiment of the present invention, the light emitting layer may be formed on at least one shell.

In the magnetic particles according to the embodiment of the present invention, the light emitting layer may be a laminated film of a plurality of light emitting layers that absorb light of different wavelengths and emit light of different wavelengths.

In the magnetic particle according to the embodiment of the present invention, the continuous gap formed between the core and the shell includes a gap, and the gap of the gap may be at least 10 nm.

In the magnetic particle according to another embodiment of the present invention, the discontinuous pores formed in the shell, the diameter of the pores forming the pores may be at least 50nm.

In the magnetic particles according to another embodiment of the present invention, the shell may include a dielectric material or a metal.

The magnetic particles according to the embodiment of the present invention may include at least one layer of metal shell made of metal on at least one layer of dielectric shell made of a dielectric material including voids.

In the magnetic particles according to an embodiment of the present invention, the gap portion may be a hollow portion having a gap of 10 to 300 nm.

In the magnetic particles according to the embodiment of the present invention, the pores may be pores having a diameter of 50 to 300 nm.

Magnetic particles according to an embodiment of the present invention may have a brightness of 65 or more.

Magnetic particles according to an embodiment of the present invention may be a security particle of the price certificate.

In another embodiment of the present invention, the method includes: applying a plurality of particles or materials for forming pores to be formed of a material that is removable by firing or chemical treatment at a high temperature on a magnetic core; Forming a shell comprising a dielectric material or a metal on the particles obtained from the previous step; The present invention provides a method of manufacturing magnetic particles including removing a plurality of particles or materials for forming voids to form a shell including voids and forming an inorganic light emitting layer.

In the method of manufacturing magnetic particles according to an embodiment of the present invention, the method may include forming a metal shell including a metal on a shell including a gap.

In the method for producing magnetic particles according to an embodiment of the present invention, the step of applying the material for forming the voids is performed by a method of polymerizing the polymer forming composition on the magnetic core, the composition for forming a polymer to prepare a polymer It may include a raw material monomer and an initiator for the following.

In the method of manufacturing magnetic particles according to an embodiment of the present invention, the forming of the hollow-forming material layer may include surface modifying the magnetic core using a coupling agent and polymerizing the composition for forming a polymer on the surface-modified magnetic core. It may be carried out by a reaction method.

In the method for producing magnetic particles according to an embodiment of the present invention, the composition for forming a polymer may include an anionic monomer as a coagulation stabilizer.

In the method for producing magnetic particles according to an embodiment of the present invention, the thickness of the pore portion may be controlled according to the content of the raw material monomer and the anionic monomer in the polymer-forming composition.

In this case, the composition for forming a polymer may include a styrene-based monomer as a raw material monomer and a sodium styrene sulfonate as an anionic monomer.

In the method for producing magnetic particles according to an embodiment of the present invention, the surface modification in the step of applying the material for forming the pores may be performed using 3-methacryloxy propyl trimethoxysilane as a coupling agent.

In the manufacturing method of the magnetic particles according to an embodiment of the present invention, the step of applying a plurality of particles for the formation of the pores is mixing and stirring the magnetic core and the pores for forming the particles in water, the separated pore forming particles are applied It can be carried out by a method comprising the step of heat treating the magnetic particles. At this time, the heat treatment may be performed in a temperature range of 100 to 110 ℃.

In this case, the pore forming particles may be vinyl polymer particles having a size of 50 to 300 nm.

Surface modification of the core can also be carried out by applying polyethylene imine.

In the method for producing magnetic particles according to an embodiment of the present invention, the step of forming a shell having pores is performed by a method of removing the magnetic particles obtained from the previous step by treating the pores forming particles or a substance with a solvent in which the substances are dissolved. Can be.

In the method of manufacturing magnetic particles according to an embodiment of the present invention, the forming of the shell having the voids may include removing the magnetic particles obtained from the previous step by firing them in a temperature range in which the material for forming the voids may be fired. Can be performed.

In the method for producing magnetic particles according to an embodiment of the present invention, the step of forming the inorganic light emitting layer is a sol-gel by dispersing the magnetic particles obtained from the previous step in a composition comprising a host-guest material and a chelate structure generating agent Can be carried out via reaction.

Magnetic particles according to one embodiment of the present invention is useful as a security particle of the deed, the security particle is a particle provided in the deed to prevent or determine the forgery and tampering of the deed.

An exemplary embodiment of the present invention provides an ink containing the magnetic particles according to the present invention as a security ink used in the manufacture of a deed, in order to prevent or discriminate forgery and tampering of the deed.

The magnetic particles according to the present invention not only have magnetic properties, but also have light emission characteristics that absorb / emit light in a specific region, thereby having strong security, very high brightness, and different from the color of the dark magnetic material itself. It has the advantage of controlling the color, can control the specific gravity of the magnetic particles, has the advantage of having a high oil absorption and a large surface area, can be used in color inks, general paints, automotive powder pigments, cosmetic pigments, catalyst paints, In particular, it is used as the security ink of the oil price certificate, there is an advantage that can conceal the area and shape to which the security particles are applied.

1 is a cross-sectional view showing an example of magnetic particles capable of forming an inorganic light emitting layer according to the present invention,
2 is a cross-sectional view showing another example of magnetic particles capable of forming an inorganic light emitting layer according to the present invention,
3 is a cross-sectional view showing another example of magnetic particles capable of forming an inorganic light emitting layer according to the present invention;
4 is a cross-sectional view showing another example of magnetic particles capable of forming an inorganic light emitting layer according to the present invention;
5 is a cross-sectional view showing another example of magnetic particles capable of forming an inorganic light emitting layer according to the present invention;
6 is a cross-sectional view showing an example of magnetic particles capable of forming an inorganic light emitting layer according to the present invention,
7 is a cross-sectional view showing another example of magnetic particles capable of forming an inorganic light emitting layer according to the present invention,
8 is a cross-sectional view showing another example of magnetic particles capable of forming an inorganic light emitting layer according to the present invention;
9 is a cross-sectional view showing another example of magnetic particles capable of forming an inorganic light emitting layer according to the present invention;
10 is a cross-sectional view showing another example of magnetic particles capable of forming an inorganic light emitting layer according to the present invention.
Description of the Related Art [0002]
1 to 5,
100: magnetic core
300: shell 200: void portion
310: shell 311 to 313 made of a metal material: first metal film to third metal film
320: shell (first shell) made of a dielectric material
321 to 323: first to third dielectric films
400: shell made of a metallic material (second shell)
401 to 402: first to second metal films constituting the second shell layer
6 to 10,
100: magnetic core
200, 200 (I), 200 (II): Shell part including voids
300: air gap (pore)
210 to 230: Dielectric shell films constituting the shell portion including the void portion, 220 is a shell containing the void portion
400: outer shell (shell made of metal)
410 ~ 420: multilayer metal shell films constituting the outer shell

Hereinafter, with reference to the accompanying drawings will be described in detail a magnetic particle and a manufacturing method of the present invention. The following drawings are provided by way of example so that those skilled in the art can fully understand the spirit of the present invention. Therefore, the present invention is not limited to the following drawings, but may be embodied in other forms, and the following drawings may be exaggerated in order to clarify the spirit of the present invention. Also, throughout the specification, like reference numerals designate like elements.

Hereinafter, the technical and scientific terms used herein will be understood by those skilled in the art without departing from the scope of the present invention. Descriptions of known functions and configurations that may be unnecessarily blurred are omitted.

In the accompanying drawings, although the magnetic particles capable of forming the inorganic light emitting layer according to the present invention are illustrated as having a spherical shape, the shape of the magnetic particles is not limited to the spherical shape.

Magnetic particles of the present invention is a magnetic core; And a shell comprising a continuous or discontinuous void formed between the core and the shell or in the shell, wherein the gap or diameter of the void is at least 10 nm; It includes an inorganic light emitting layer.

1 to 5 are examples of particles that can be applied to form an inorganic light emitting layer as a magnetic core; And a shell, wherein the particle includes a continuous void portion between the core and the shell, but is not limited thereto. The continuous void portion may be understood as a hollow portion.

As shown in FIG. 1, magnetic particles applicable to forming an inorganic light emitting layer according to the present invention include a magnetic core 100; The shell 300 may be included, and the air gap 200 may be included between the magnetic core 100 and the shell 300.

The magnetic core 100 imparts magnetic properties to the magnetic particles according to the present invention, and the void portion 200 serves to adjust the color differently from the color of the magnetic material of the dark color itself, The specific gravity can be controlled and the magnetic particles having a high oil absorption and a large surface area can be produced, and the proper brightness can be maintained.

Meanwhile, the shell 300 includes a metal or a dielectric, which may be a single layer or a multilayer, and may be made of the same or different materials.

As an example, FIG. 2 illustrates a case where the shell is made of a metal material, and FIG. 3 illustrates a case where the shell is made of a dielectric material.

The shell 310 of metal material in FIG. 2 is a single layer (a, 310 in FIG. 2), two layers (b, 311, 312 in FIG. 2) or three layers (c, 311, 312 and 313 in FIG. 2). ) Or more.

 Based on FIG. 2, when the shell 300 is a shell 310 made of a metal material, the magnetic particles I according to the present invention will be described in detail.

As shown in FIG. 2, the magnetic particles I include a shell 310 made of a metal material; Magnetic core 100; And an air gap 200 which is an empty air layer between the sphere of the shell 310 made of a metal material and the core.

The magnetic particles (I) according to the present invention, the magnetic core 100 is located to impart magnetic properties to the magnetic particles (I), the void portion 200 increases the specific surface area of the magnetic particles (I) according to the present invention. In addition, the specific gravity of the magnetic particles (I) may be lowered, and the visible light wavelength band reflected by the magnetic particles (I) may be adjusted. Furthermore, the brightness can be increased. In particular, the advantage of placing the void portion 200 is to improve the oil absorption of the magnetic particles, which can improve the compatibility when the magnetic particles are applied to the ink composition, improve the thixotropy To improve the printability.

In detail, the magnetic core 100 of the magnetic particles (I) is a ferromagnetic particle, the magnetic core 100 is iron; nickel; cobalt; Iron oxide; Nickel oxide; Cobalt oxide; And at least one selected from the group consisting of a multicomponent material comprising at least two elements selected from iron, nickel, and cobalt.

The magnetic core 100 preferably has a size of 0.1 μm or more in order to prevent deterioration of magnetic properties over time, and may be adjusted in consideration of a field in which magnetic particles (I) are utilized. When the magnetic ink (I) is contained in the security ink, the size of the magnetic core 100 is preferably 0.5 to 50㎛.

The shell 310 made of the metal material increases the brightness of the magnetic particles (I). The metal material included in the shell 310 of the metal material is preferably at least one selected from copper, nickel, gold, platinum, silver, aluminum, and chromium, and at least one from copper, nickel, silver, and chromium. More preferably, it is the selected material.

In this case, the shell 310 made of the metal material may be a single film made of a single metal sphere, or may be a multilayer film in which films of different metals are stacked.

In detail, when the structure of the shell 310 of the metal material is a single film, the single film is preferably one or more materials selected from platinum, silver, aluminum, and chromium, and the shell of the shell 310 of the metal material. The thickness is preferably 10 to 500 nm in terms of increasing the brightness of the magnetic particles (I).

In detail, the sphere of the shell 310 made of the metal material includes a laminated film in which two or more metal films, which are different metals, are stacked, and as shown in FIGS. 2 (b) to 2 (c), the first metal The laminated film in which the film 311 and the second metal film 312 are laminated, or as shown in FIG. 2C, the first metal film 311, the second metal film 312, and the third metal film The layered film 313 is laminated.

Preferably, the metals of the first metal film 311 to the third metal film 313 are different from each other and are made of at least one material selected from copper, nickel, gold, platinum, silver, aluminum, and chromium. The metal film 311 It is preferable that the total thickness (ie, the thickness of the shell 310 made of a metal material) of the laminated film in which? 313 is laminated is 40 to 150 nm like the single film.

The air gap between the sphere of the shell 310 made of a metal material and the core 100, the air gap 200, reduces the volume to mass of the magnetic particles I in the shell 310 made of the metal material, thereby reducing the amount of magnetic particles. It lowers the specific gravity of (I) and increases the specific surface area of the magnetic particles (I). It also increases oil absorption. In addition, by forming a layer having a refractive index of air to reflect the light in the visible light band to increase the brightness of the magnetic particles (I), and to reflect the visible light of a certain wavelength more to make the magnetic particles (I) have a constant color. Can be.

Magnetic particles including the inorganic light emitting layer of the present invention can be manufactured using the magnetic particles (I), wherein the inorganic light emitting layer preferably constitutes the outermost shell in terms of improving luminous efficiency.

In the inorganic light emitting layer, Erbium, Europium, Ytterbium, Holmium, Thulium, and the like may be used as the guest material of the material forming the shell. It can be freely changed according to the light emitting area. Yttrium, Gadolinium, Vanadium, Zinc, Titanium, and their oxidizing compounds may be used as host materials for the shell-forming materials that may be used. The material capable of transferring electrons to the guest material is not particularly limited. For example, the light emitting layer may include a compound having a host: guest combination of YVO 4 : Eu, YVO 4 : Er, YVO 4 : Nd, YVO 4 : Ho, and YVO 4 : Tm. Due to the nature of the present invention in which the shell uniformly surrounds the core, the polymer structure generating agent may be variously changed according to the purpose.

Such a light emitting layer may be formed on one shell or may be formed on several shells.

In particular, when a metal layer having reflective characteristics is formed inside the light emitting layer, it may be advantageous in terms of increasing the light emitting efficiency of the light emitting layer.

In addition, the light emitting layer may further enhance security in the case of a laminated film of a plurality of light emitting layers that absorb light of different wavelengths and emit light of different wavelengths.

As described above, the magnetic particles including the inorganic light emitting layer may provide not only magnetic properties expressed in the magnetic core but also light emitting properties in which the light emitting material absorbs / emits light in a specific area, thereby providing a forgery preventing magnetic material having strong security. Can be.

The magnetic particles having the inorganic light emitting layer obtained by using the magnetic particles (I) according to the present invention have a specific gravity similar to that of oil, have a brightness of 65 or more, and have a different color from that of the core, so that the thickness of the pore portion 200 is different. Is preferably from 10 to 300 nm.

The method of manufacturing the magnetic particles (I) described above is not particularly limited, but for example, forming a material layer for forming pores on the magnetic core, which is removable by heat treatment or chemical treatment (s11); The method may include forming a shell layer including a metal on the pore forming material layer (s12) and forming a pore by removing the pore forming material layer (s13).

In step s11, the pore forming material layer may be a layer including a vinyl polymer. In particular, considering the magnetic core may be a layer containing a polystyrene polymer preferably.

The formation of the pore forming material layer may be performed using a polymer dissolving solution, but is preferably formed through polymerization of the polymer forming composition on the core in terms of forming a monodisperse layer. In this case, the composition for forming a polymer may include a raw material monomer for preparing a polymer and an initiator for initiating a polymerization reaction, and preferably, the composition for forming a polymer includes a coagulation stabilizer. In the case of including a coagulation stabilizer, the polymerization may be performed on the core to form an even surface without agglomeration of the polymer.

In a specific embodiment of the present invention, the composition for forming a polymer used to form the material layer for forming the pore portion is a raw material monomer is a styrene-based monomer, the aggregation stabilizer may use sodium styrenesulfonate. The initiator used azobisisobutyronitrile (AIBN), but is not limited thereto.

On the other hand, in the formation of a homogeneous single dispersion film in forming such an organic pore forming material layer on the core, the step of forming the pore forming material layer is a surface modification of the magnetic core using a coupling agent Next, a method of polymerizing the polymer-forming composition on the surface-modified core may be considered. At this time, the coupling agent may be adjusted according to the composition for forming the polymer. In one embodiment of the present invention, the coupling agent may be methacryloxy propyl trimethoxysilane.

As such, when the core is surface-modified and polymerized on the surface-modified core to form a polymer layer, the polymer-ferromagnetic composite may be formed, and the obtained polymer layer may have a homogeneously coated film.

Specifically, the magnetic particles or the surface-modified magnetic particles are mixed and stirred, wherein the temperature may be preferably in the range of 20 to 70 ℃ in consideration of polymerization.

Forming a shell made of a metal material in the polymer-ferromagnetic composite obtained through the step s11, that is, step s12 is impregnated with the polymer-ferromagnetic composite in a metal precursor solution in which a precursor of a metal forming a metal film is dissolved, and then a reducing agent To form a metal film in the polymer-ferromagnetic composite.

Next, the pore forming material layer is removed from the magnetic particles formed as the metal shell / pore forming material layer / core obtained through the step s12 (s13), wherein the removing may be performed thermally or chemically and chemically removed. Means that the polymer layer is dissolved and removed by dissolving the polymer, and thermal polymer removal means thermally decomposing the polymer by thermally treating the metal-polymer-ferromagnetic complex in an inert gas.

By preparing the magnetic particles (I) as described above and forming an inorganic light emitting layer therein, magnetic particles having the light emitting layer in the outermost shell can be obtained.

In this case, the forming of the inorganic light emitting layer may be performed through a sol-gel reaction by dispersing the magnetic particles obtained from the previous step in a composition including a host-guest material and a chelate structure generating agent.

On the other hand, the magnetic particles (II) will be described in detail as an example of other magnetic particles that can be used to produce the magnetic particles having the inorganic light emitting layer of the present invention. This is the case in which the shell 300 is a shell 320 made of a dielectric material, and as shown in FIG. 3A, the magnetic particles II may include a shell 320 made of a dielectric material; A magnetic core 100 located in the inner hollow of the shell 320 of a dielectric material; And a void portion 200, which is an empty air layer between the sphere of the shell 320 made of a dielectric material and the magnetic core 100, and as shown in FIG. 4B. Preferably comprises a shell 400 (hereinafter referred to as a second shell) made of a metal material surrounding the shell 320 made of a dielectric material at the outermost part of the particle (II).

In the magnetic particle (II) according to the embodiment of the present invention as described above, the magnetic core 100 is positioned to impart magnetic properties to the magnetic particles (II), and the shell 320 made of a dielectric has a pore portion 200. Together, by forming a layer in which the difference in refractive index is maximized inside the magnetic particles (II), the brightness of the magnetic particles (II) may be increased, and the visible light wavelength band reflected by the magnetic particles (II) may be adjusted.

In detail, the magnetic core 100 of the magnetic particles (I) is a ferromagnetic particle, the magnetic core 100 is iron; nickel; cobalt; Iron oxide; Nickel oxide; Cobalt oxide; And at least one selected from the group consisting of a multicomponent material comprising at least two elements selected from iron, nickel, and cobalt.

The magnetic core 100, similar to the core 100 of the magnetic particles (I), preferably has a size of 0.1 ㎛ or more in order to prevent deterioration of the magnetic properties over time, the magnetic particles (II) is utilized Adjust the size considering the field. When the magnetic ink (II) is contained in the security ink, the size of the magnetic core 100 is preferably 0.5 to 50㎛.

As shown in FIG. 3B, the second shell 400 made of the metal material is preferably formed in the outermost layer of the magnetic particles II, and the second shell 400 is made of a dielectric material. The brightness of the magnetic particles II is increased together with the shell 320 (hereinafter, referred to as a first shell) and the air gap 200.

The second shell 400 made of a metal material is preferably a material selected from at least one selected from copper, nickel, gold, platinum, silver, aluminum, and chromium, similar to the shell made of the metal material of the magnetic particles (I). More preferably at least one selected from copper, silver and chromium.

The thickness of the second shell 400 is preferably 40 to 150 nm. The brightness of the magnetic particles II is increased by the second shell 400.

In this case, as shown in FIG. 4, the second shell 400 made of the metal material may be a single film composed of a single metal film, and a multilayer film in which films 401 to 402 of different metals are stacked. Can be.

In detail, the second shell 400 may include a laminated film in which two or more metal films, which are different metals, are stacked. 5 illustrates an example in which the second shell 400 is formed by stacking two layers of metal films (the first metal shell film 401 and the second metal shell film 402), but the present invention It is not limited to the number of this laminated metal film. In this case, as shown in FIG. 5, the thickness of the laminated film in which the first metal shell film 401 and the second metal shell film 402 are stacked (that is, the total thickness of the metal shell) is preferably 40 to 150 nm like the metal shell of the single film. .

The air gap between the structure of the first shell 320 and the magnetic core 100 forms a layer having a refractive index of air in the magnetic particles II, and the first shell 320 is formed of the metal. A layer having a refractive index greater than that of air is formed between the second shell 400 and the air gap 200. The dielectric material of the first shell 320 is preferably at least one selected from the group consisting of titanium dioxide, silicon dioxide, alumina, calcium carbonate, zirconium oxide, magnesium fluoride, zinc oxide, and zinc sulfide. 320) The thickness of the spheres is preferably 10 to 500 nm.

The magnetic particles (II) according to the present invention adopts a configuration of the first shell 320 together with the void portion 200, thereby providing a layer having a refractive index of air of the void portion 200 and a first shell having a high refractive index. The composition of 320 increases the brightness of the magnetic particles (II) according to the present invention, and adjusts the visible light wavelength band reflected by the magnetic particles (II). Further, the gap 200 lowers the specific gravity of the magnetic particles (II) and increases the specific surface area.

In detail, the air gap 200, which is an air layer between the sphere of the first shell 320 and the magnetic core 100, forms a layer having a refractive index of air in the first shell 320, and has a visible light band. By reflecting the brightness of the magnetic particles (II) can be increased. In addition, by reducing the volume to mass of the magnetic particles (II) to lower the specific gravity of the magnetic particles (II), it increases the specific surface area of the magnetic particles (II). In addition, in particular, the advantage of placing the void portion 200 is to improve the oil absorption of the magnetic particles, which can improve the compatibility when the magnetic particles are applied to the ink composition, the thixotropy By improving the printability can be improved.

In this case, as shown in FIG. 5, the sphere of the first shell 320 includes a laminated film in which two or more inorganic films having different refractive indices are stacked. 5 illustrates three dielectric films (the first dielectric film 321, the second dielectric film 322, and the third dielectric film) in which the structure of the first shell 320 has three different refractive indices. (323) is an example showing the case of lamination, but the present invention is not limited to the number of the laminated dielectric films.

The magnetic particles II having the structure of the first shell 320, the magnetic core 100, the cavity 200, and the second shell 400 are light in weight, have a large specific surface area and high oil absorption. It is characterized by high brightness and constant color.

Magnetic particles including the inorganic light emitting layer of the present invention may be manufactured using the magnetic particles (II), and in this case, the inorganic light emitting layer preferably constitutes the outermost shell in terms of improving luminous efficiency.

In the inorganic light emitting layer, Erbium, Europium, Ytterbium, Holmium, Thulium, and the like may be used as the guest material of the material forming the shell. It can be freely changed according to the light emitting area. Yttrium, Gadolinium, Vanadium, Zinc, Titanium, and their oxidizing compounds may be used as host materials for the shell-forming materials that may be used. The material capable of transferring electrons to the guest material is not particularly limited. For example, the light emitting layer may include a compound having a host: guest combination of YVO 4 : Eu, YVO 4 : Er, YVO 4 : Nd, YVO 4 : Ho, and YVO 4 : Tm. Due to the nature of the present invention in which the shell uniformly surrounds the core, the polymer structure generating agent may be variously changed according to the purpose.

Such a light emitting layer may be formed on one shell or may be formed on several shells.

In particular, when a metal layer having reflective characteristics is formed inside the light emitting layer, it may be advantageous in terms of increasing the light emitting efficiency of the light emitting layer.

In addition, the light emitting layer may further enhance security in the case of a laminated film of a plurality of light emitting layers that absorb light of different wavelengths and emit light of different wavelengths.

As described above, the magnetic particles including the inorganic light emitting layer may provide not only magnetic properties expressed in the magnetic core but also light emitting properties in which the light emitting material absorbs / emits light in a specific area, thereby providing a forgery preventing magnetic material having strong security. Can be.

Meanwhile, the method of manufacturing the magnetic particles (II) described above is not limited thereto. For example, the method may further include forming a material layer for forming void portions on the core (s21); Forming a first shell layer including a dielectric material on the pore forming material layer (s22); Forming a second shell layer including the metal on the first shell layer (s23); And removing the pore forming material layer to form the pore (S24).

On the magnetic core, in the forming of the pore forming material layer (s21), the pore forming material layer may be a layer including a vinyl polymer. In particular, considering the magnetic core may be a layer containing a polystyrene polymer preferably.

The formation of the pore forming material layer may be performed using a polymer dissolving solution, but is preferably formed through polymerization of the polymer forming composition on the core in terms of forming a monodisperse layer. In this case, the composition for forming a polymer may include a raw material monomer for preparing a polymer and an initiator for initiating a polymerization reaction, and preferably, the composition for forming a polymer includes a coagulation stabilizer. In the case of including a coagulation stabilizer, the polymerization may be performed on the magnetic core to form an even surface without aggregation of the polymer.

In a specific embodiment of the present invention, the composition for forming a polymer used to form the material layer for forming the pore portion is a raw material monomer is a styrene-based monomer, the aggregation stabilizer may use sodium styrenesulfonate. The initiator used azobisisobutyronitrile (AIBN), but is not limited thereto.

On the other hand, in forming such an organic-type pore forming material layer on the core in the form of a homogeneous single dispersion film, forming the pore forming material layer is a surface-modified core using a coupling agent Next, a method of polymerizing the polymer-forming composition on the surface-modified magnetic core may be considered. At this time, the coupling agent may be adjusted according to the composition for forming the polymer. In one embodiment of the present invention, the coupling agent may be methacryloxy propyl trimethoxysilane.

As such, when the magnetic core is surface-modified and polymerized on the surface-modified magnetic core to form a polymer layer, a polymer-ferromagnetic composite may be formed, and the obtained polymer layer may have a homogeneously coated membrane. .

Specifically, the magnetic particles or the surface-modified magnetic particles are mixed and stirred, wherein the temperature may be preferably in the range of 20 to 70 ℃ in consideration of polymerization.

The forming of the first shell layer and the second shell layer including the metal in the polymer-ferromagnetic composite may include impregnating the polymer-ferromagnetic composite in the metal precursor solution (II), and then adding a reducing agent to the metal in the polymer-ferromagnetic composite. It is preferable to form a film or to form a metal film on the polymer-ferromagnetic composite by physically mixing and stirring a polymer-ferromagnetic composite and a metal particle, and then to oxidize the formed metal film to prepare an inorganic-polymer-ferromagnetic composite.

In a specific embodiment, the thickness of the shell layer may be controlled according to the reaction temperature in forming the shell of the dielectric material. When the dielectric material is titanium oxide, the reaction temperature may be about 20 to 85 ° C.

In addition, the removal of the pore-forming material layer may be performed thermally or chemically, and the chemical polymer removal may be performed by dissolving the polymer layer with an organic solution that dissolves the polymer, and the thermal polymer removal may be performed by removing the metal-inorganic-polymer- It means that the ferromagnetic composite is heat-treated to remove the polymer by thermal decomposition.

On the other hand, steps s23 and s24 may be performed in a reverse order. That is, it is also possible to form a first shell layer, then to form a void, and then to form a second shell layer on the first shell layer.

By preparing the magnetic particles (II) as described above and forming an inorganic light emitting layer therein, magnetic particles having the light emitting layer in the outermost shell can be obtained.

In this case, the forming of the inorganic light emitting layer may be performed through a sol-gel reaction by dispersing the magnetic particles obtained from the previous step in a composition including a host-guest material and a chelate structure generating agent.

Meanwhile, the particles shown in FIGS. 6 to 10 are examples of other types of particles applicable to forming an inorganic light emitting layer. FIGS. 6 to 10 include a magnetic core; And a shell, and examples of magnetic particles including discontinuous pores formed in the shell, but are not limited thereto.

First, the magnetic particles shown in FIG. 6 include a magnetic core 100; And a shell portion 250 comprising a void portion, the shell portion comprising a shell containing a plurality of voids, ie, a discontinuous void portion.

The magnetic core 100 is to impart magnetic properties to the magnetic particles, the shell portion 250 including the void portion is configured to control the specific gravity, specific surface area or oil absorption of the magnetic particles, in addition to the brightness of the magnetic particles or It may be a configuration that also affects color.

Specifically, the magnetic core 100 of the magnetic particles (III) are ferromagnetic particles, the magnetic core 100 is iron; nickel; cobalt; Iron oxide; Nickel oxide; Cobalt oxide; And at least one selected from the group consisting of a multicomponent material comprising at least two elements selected from iron, nickel, and cobalt.

The voids 350 (hereinafter referred to as " pore ") are uniformly and regularly discontinuously distributed in the shell film of the shell portion 250 including the void portions, and the regular distribution is the closest pore based on a single pore. It means that the number is constant, the number of the closest pores includes 5 to 6, it is preferable that the number of the closest pores.

The pores 350 include shapes that are circular, elliptical, or polygonal in cross section, and the pores are preferably spherical in view of increasing homogeneity of the surface of the particles.

As shown in FIG. 7, the shell part 250 including the voids may be a dielectric shell 250 (I) or a metal shell 250 (II), and the shell part 250 including the voids is a dielectric. As illustrated in FIG. 9, the magnetic particles may further include a metal shell 400 (hereinafter, referred to as an “outer shell”) surrounding the shell portion 250 including an air gap portion.

As shown in FIG. 8, the shell portion 250 including the void portion, which is the dielectric shell 250 (I) or the metal shell 250 (II), is a single film or the void containing shell 220 which becomes a shell including the void portion. Including a, it may be a laminated film in which the films 210 and 230 made of different materials are stacked.

In the case where the shell portion 250 including the voids is a single film made of a shell including voids, as shown in FIG. 1, the pores 350 are closed pores having no openings on the surface of the shell portion 250 including the voids. It is preferable.

That is, it is preferable that the diameter of the pore 350 is about the same as compared with the thickness of the shell part 250 containing a space part.

In this case, the meaning of the closed pores means that the particles of the material constituting the shell part 250 including the pores are connected to each other and exist as a layer between the pores and the air, and the pores are present between the pores and the air. The layer in which the particles of the material constituting the shell part 250 are connected to each other includes a layer in which nano pores through which gas is permeated are present.

When the shell part 250 including the voids is a laminated film including a shell having voids, as shown in FIGS. 8A to 8C, the shell parts 250 including the voids may be different from each other. The film includes a laminated film in which two or more films are laminated. FIG. 8A illustrates the shell part 250 including the air gap portion in the form of a laminated film in which the first shell 210 is stacked on the shell 220 including the air gap portion, and FIGS. 8 (b) to 8 ( c) is a void portion having a second shell 230 formed on the shell including the void portion and laminated on an inner layer of the shell including the void portion or contained within the shell containing the void portion. It shows a shell portion 250 that includes.

In the shell part 250 including the gap part, only the case in which the shell part 250 includes the gap part is illustrated, but pores may be formed in the first shell, the second shell, etc. constituting the shell part 250 including the gap part. Of course.

More specifically, when the shell including pores having pores in the shell part 250 including pores is further formed, pores are formed only in the film in contact with the magnetic core 100 as shown in FIG. To form a shell 220 including voids, as shown in FIG. 8B, except for the innermost cornea 230 contacting the magnetic core 100 and the outermost cornea 210 forming a surface. In addition, pores may be formed in a single film (only 220 of FIG. 8) selected between the innermost cornea 230 and the outermost cornea 210, and although not shown in the drawing, the outermost cornea 210 is formed. The pores may be formed in).

More specifically, when the pores are formed in two or more films selected from two or more films constituting the laminated film, as shown in Fig. 8C, the diameter of the pores is larger than the thickness of the film as long as the laminated films are formed. In addition, pores may be formed across the interface of the two or more films 230 and 220.

The pores 350 having a refractive index of air may serve to lower specific gravity of the magnetic particles, increase specific surface area, and improve oil absorption. In addition, it helps maintain proper brightness.

In detail, the pores 350 reduce the specific gravity of the magnetic particles by reducing the volume to mass of the magnetic particles, and increase the specific surface area of the magnetic particles. In particular, the advantage of forming the pores 350 is to improve the oil absorption of the magnetic particles, which can improve the compatibility when applying the magnetic particles to the ink composition, improve the thixotropy printing Improve your aptitude.

More specifically, the diameter of the pores 350 is preferably 50 to 300 nm so as to have a proper oil absorption, the magnetic particles have a specific gravity similar to oil, have a brightness of 65 or more, and have a color different from that of the magnetic core.

Preferably, in the magnetic particles (III) described above with reference to FIGS. 6 to 8, the shell material of the shell portion 250 including the void portion is preferably a dielectric material, and the dielectric material is preferably titanium dioxide or silicon dioxide. And at least one selected from the group consisting of alumina, calcium carbonate, zirconium oxide, magnesium fluoride, zinc oxide and zinc sulfide.

By adopting the dielectric material as the shell portion 250 including the pores, the dielectric material along with the pore diameter can form a layer in which the refractive index difference is maximized inside the magnetic particles, thereby increasing the brightness of the magnetic particles.

Similar to the example shown in FIG. 8, when the shell part 250 including the voids is a laminated film in which two or more dielectric films are stacked, the two or more films 210 to 230 constituting the shell part including the voids are different from each other. It is preferable that two or more dielectric films having refractive indices are stacked, and the shell part 250 including voids is formed of a laminated film, thereby further increasing the reflectance of visible light reflected from the magnetic particles. At this time, the thickness of the shell film (including a single film or a laminated film) of the shell part 250 including the void portion is preferably 100 to 500 nm.

On the other hand, as shown in Figure 9, when the shell portion 250 including the void portion is a dielectric, it is preferable that the magnetic particles further comprise a metal shell (400, hereinafter outer shell) surrounding the shell containing the void portion. . The outer shell 400 surrounding the void containing shell may serve to further increase the brightness of the magnetic particles.

The outer shell 400 is preferably at least one material selected from copper, nickel, gold, platinum, silver, aluminum and chromium, and more preferably at least one material selected from nickel, copper, silver and chromium.

In this case, as shown in FIG. 9, the outer shell 400 may be a single layer formed of a single metal sphere, and as illustrated in FIG. 5, layers 410 to 420 of different metals (metal shell layers) are stacked. It may be a multilayer film.

In detail, when the outer shell 400 is a single film, the single film is preferably at least one material selected from platinum, silver, aluminum, and chromium, and the thickness of the outer shell 400 is preferably 40 to 150 nm. This increases the brightness of the magnetic particles, it may be preferable in terms of controlling the color of the pores of the magnetic particles by the pores formed in the shell portion 250 including the voids.

In detail, the outer shell 400 may include a multilayer film in which two or more metal films, which are different metals, are stacked. 10 illustrates an example in which the outer shell 400 is formed by stacking two metal films (the first metal shell film 410 and the second metal shell film 420), but the present invention is described above. It is not limited to the number of laminated metal films.

The metal of the first metal shell film 410 and the second metal shell film 420 is preferably one or more materials selected from copper, nickel, gold, platinum, silver, aluminum, and chromium, and the first metal shell film 410 ) And the thickness of the multilayer film (that is, the total thickness of the metal shell) on which the second metal shell film 420 is stacked are preferably 40 to 150 nm, similarly to the metal shell of the single film.

Specifically, the magnetic core 100 of the magnetic particles (III) are ferromagnetic particles, the magnetic core 100 is iron; nickel; cobalt; Iron oxide; Nickel oxide; Cobalt oxide; And at least one selected from the group consisting of a multicomponent material comprising at least two elements selected from iron, nickel, and cobalt.

The magnetic core 100 preferably has a size of 0.1 μm or more in order to prevent deterioration of magnetic properties over time, and may be adjusted in consideration of a field in which magnetic particles are utilized. When magnetic particles are contained in the security ink, the size of the magnetic core 100 is preferably 0.5 to 50㎛.

Magnetic particles including the inorganic light emitting layer of the present invention can be manufactured using the magnetic particles (III), wherein the inorganic light emitting layer preferably constitutes the outermost shell in terms of increasing the luminous efficiency.

In the inorganic light emitting layer, Erbium, Europium, Ytterbium, Holmium, Thulium, and the like may be used as the guest material of the material forming the shell. It can be freely changed according to the light emitting area. Yttrium, Gadolinium, Vanadium, Zinc, Titanium, and their oxidizing compounds may be used as host materials for the shell-forming materials that may be used. The material capable of transferring electrons to the guest material is not particularly limited. For example, the light emitting layer may include a compound having a host: guest combination of YVO 4 : Eu, YVO 4 : Er, YVO 4 : Nd, YVO 4 : Ho, and YVO 4 : Tm. Due to the nature of the present invention in which the shell uniformly surrounds the core, the polymer structure generating agent may be variously changed according to the purpose.

Such a light emitting layer may be formed on one shell or may be formed on several shells.

In particular, when a metal layer having reflective characteristics is formed inside the light emitting layer, it may be advantageous in terms of increasing the light emitting efficiency of the light emitting layer.

In addition, the light emitting layer may further enhance security in the case of a laminated film of a plurality of light emitting layers that absorb light of different wavelengths and emit light of different wavelengths.

As described above, the magnetic particles including the inorganic light emitting layer may provide not only magnetic properties expressed in the magnetic core but also light emitting properties in which the light emitting material absorbs / emits light in a specific area, thereby providing a forgery preventing magnetic material having strong security. Can be.

6 to 10 is not particularly limited to the method of manufacturing the magnetic particles shown in FIG. 10, but as an example will be described in consideration of the method of manufacturing the magnetic particles shown in FIG.

First, a plurality of void forming particles are coated on the magnetic core (s11).

The pore-forming particles are made of a material that can be removed by firing or chemical treatment at a high temperature, specifically, vinyl polymer particles, and more specifically, polystyrene particles.

The size of the pore forming particles may be adjusted according to the size of the desired pores, preferably 50 to 300nm.

In order to increase the binding force between the magnetic particles forming the core and the particles for forming the voids, a surface-modified one may be used as the core. That is, the surface modification of the core particles may be performed to increase the bonding force between the polymer particles and the core particles before applying the particles for forming voids on the core.

Surface modification of the core particles includes forming a polymer film using a polymer solution in which a polymer different from the particles for forming voids is dissolved on the surface of the core particles. In a specific embodiment of the present invention, polyethylene imine is used for surface modification to mix particles serving as cores in a solution of polyethylene imine to form a polyethylene imine membrane on the surface thereof.

Meanwhile, in the step of attaching the polymer particles to the surface of the core particles, it is preferable to mix and stir the magnetic core particles and the polymer particles, and to recover the core particles obtained so that the polymer particles are evenly attached to the core particles. In this case, further performing the heat treatment of the separated magnetic particles is preferable in terms of improving the adhesion efficiency of the polymer particles, and preferably, the heat treatment is preferably performed at 100 to 110 ° C. in terms of adhesion efficiency.

After applying a plurality of particles for forming pores on the magnetic core through the step s11, a shell including a dielectric material is formed according to an embodiment of the present invention (step s12).

In this case, the shell including the dielectric material impregnates the magnetic precursor obtained from step s11 in the metal precursor solution (I) in which the precursor of the metal forming the dielectric material film is dissolved, and then adds an oxidant to form a metal oxide film in the polymer-ferromagnetic composite. Alternatively, a method of mixing and stirring the metal precursor solution (I) in which the magnetic body obtained from the step s11 and the metal precursor forming the dielectric film is dissolved may be mentioned.

Next, the particles for forming voids are removed to form a shell (shell containing voids) in which a plurality of pores (pores) are formed (step s13).

Removal of the pore forming particles may be performed thermally or chemically, preferably thermally. The removal of chemical polymer particles means that the polymer particles are dissolved and removed by an organic solution for dissolving the polymer. The removal of the thermal polymer particles means thermally decomposing the pore-forming particles by thermally treating the magnetic material of the previous step.

Next, on the shell with voids, an outer shell containing metal is formed (step s14).

The forming of the outer shell including the metal may be performed by impregnating the metal oxide-polymer-ferromagnetic complex into the metal precursor solution (II) in which the precursor of the metal forming the metal film is dissolved, and then adding a reducing agent to the metal oxide-polymer- A metal film is formed on the ferromagnetic composite, or the metal oxide-polymer-ferromagnetic composite and particles of metal forming the metal film are mixed and stirred to form a metal film on the surface of the metal oxide-polymer-ferromagnetic composite.

As described above, the metal film is a material selected from at least one of copper, nickel, gold, platinum, silver, aluminum and chromium, so that the formation of the metal film is obtained from the previous step.

In the above-described process, steps s13 and s14 may be performed in reverse order. In addition, it is possible to add a predicted process such as a process for forming a multilayer to generate the magnetic particles of the various embodiments described above, and also omit the process according to the deformation of the structure.

By preparing the magnetic particles (III) as described above and forming an inorganic light emitting layer therein, magnetic particles having the light emitting layer in the outermost shell can be obtained.

In this case, the forming of the inorganic light emitting layer may be performed through a sol-gel reaction by dispersing the magnetic particles obtained from the previous step in a composition including a host-guest material and a chelate structure generating agent.

The following is described by way of example for the detailed description of the invention, the invention is not limited to the following examples.

<Formation of polymer layer on magnetic core>

 Example 1

5 g of iron powder (BASF 025, "core particles") with an average diameter of 1 µm and 3 g of 3-methacryloxy propyl trimethoxysilane (MPS) (Aldrich) were dissolved in 150 ml of ethanol, and then 3 ml of ammonia was added to the solution. After stirring for 24 hours at a rotational speed of 300 rpm, the core particle surface was treated with 3-methacryloxy propyl trimethoxysilane (MPS) (Aldrich) (surface modification of the core particle). The treated core particle powder was separated by magnet and washed twice with ethanol.

2 g of core particle powder treated with 3-methacryloxy propyl trimethoxysilane (MPS) dried after washing, 1.5 ml of styrene monomer, 0.4 g of sodium styrene sulfonate (Aldrich) and 0.4 g of AIBN (2,2'-azobisisobutylronitrile) 0.2 g of (Aldrich) was added to 120 ml of ethanol, and the mixture was stirred at a rotational speed of 300 rpm for 4 hours under a nitrogen atmosphere at a temperature of 65 ° C. to form a polymer layer on the surface of the core particles. The core particle powder in which the polymer layer was formed was separated by a magnet, washed twice with ethanol, and dried. At this time, the thickness of the polymer layer was 30 nm.

[Example 2]

5 g of iron powder (BASF 025, "core particles") with an average diameter of 1 µm and 3 g of 3-methacryloxy propyl trimethoxysilane (MPS) (Aldrich) were dissolved in 150 ml of ethanol, and then 3 ml of ammonia was added to the solution. After stirring for 24 hours at a rotational speed of 300 rpm, MPS (3-methacryloxy propyl trimethoxysilane) was treated on the surface of the core particles (surface modification of the core particles). The treated core particle powder was separated by magnet and washed twice with ethanol.

1 g of core particles powder treated with 3-methacryloxy propyl trimethoxysilane (MPS) dried after washing, 2 ml of styrene monomer, 0.02 g of sodium styrene sulfonate (Nads) (Aldrich) and 0.2 g of potassium persulfate (KPS) 0.2 g Into a mixed solvent of 65 ml and 35 ml of distilled water and mixed, and stirred at a rotational speed of 300 rpm in a nitrogen atmosphere for 4 hours while the temperature of the solution was adjusted to 65 ℃ to form a polymer layer on the core particle surface. The core particle powder in which the polymer layer was formed was separated by a magnet, washed twice with ethanol, and dried. At this time, the thickness of the polymer layer was 30 nm.

[Examples 3 to 5]

5 g of iron powder (BASF 025, "core particles") with an average diameter of 1 µm and 3 g of 3-methacryloxy propyl trimethoxysilane (MPS) (Aldrich) were dissolved in 150 ml of ethanol, and then 3 ml of ammonia was added to the solution. After stirring for 24 hours at a rotational speed of 300 rpm, MPS (3-methacryloxy propyl trimethoxysilane) was treated on the surface of the core particles (surface modification of the core particles). The treated core particle powder was separated by magnet and washed twice with ethanol.

2 g of core particle powder treated with 3-methacryloxy propyl trimethoxysilane (MPS) dried after washing, styrene monomer (Aldrich), sodium styrene sulfonate (NaSS) (Aldrich) and AIBN (2,2'-azobisisobutylronitrile) (Aldrich) 0.2 The mixture was added to 120 ml of ethanol, and the mixture was stirred at a rotational speed of 300 rpm while purging with nitrogen for 4 hours while adjusting the temperature of the solution to 65 ° C. to form a polymer layer on the surface of the core particles. At this time, the change in the thickness of the polymer layer according to the change in the styrene monomer and NaSS content was measured by transmission electron microscope ( FEI, model name Tecnai G2 F30 ) and the results are shown in Table 1 below.

Example 3 Example 4 Example 5 Styrene Monomer Amount 0.4 ml 1.6 ml 3.2 ml NaSS amount 0.1 g 0.4 g 0.8 g Polymer layer thickness 10 nm 50 nm 60 nm

[Example 6]

5 g of iron powder (BASF 025, "core particles") with an average diameter of 1 µm and 3 g of 3-methacryloxy propyl trimethoxysilane (MPS) (Aldrich) were dissolved in 150 ml of ethanol, and then 3 ml of ammonia was added to the solution. After stirring for 24 hours at a rotational speed of 300 rpm, MPS (3-methacryloxy propyl trimethoxysilane) was treated on the surface of the core particles (surface modification of the core particles). The treated core particle powder was separated by magnet and washed twice with ethanol.

After washing, 2 g of dried MPS (3-methacryloxy propyl trimethoxysilane) -treated core particle powder, 1.6 ml of styrene monomer (Aldrich) and 0.2 g of AIBN (2,2'- azobisisobutylronitrile) (Aldrich) were mixed in 120 ml of ethanol. And the temperature of the solution was adjusted to 65 ℃ stirred for 4 hours at a rotational speed of 300 rpm in a nitrogen atmosphere to form a polymer layer on the surface of the core particles.

At this time, the change of the reaction result according to the change of NaSS content was measured by transmission electron microscope ( FEI Co., Model name Tecnai G2 F30 ) is shown in Table 2 below.

Example 4 Example 6 Styrene Monomer Amount 1.6 ml 1.6 ml NaSS amount 0.4 g - Reaction result 50 nm uniform polymer layer formation Polymers entangled together to form a lump

From the results of Table 2, it can be seen that NaSS, a coagulation stabilizer, prevents coagulation of the polymer and forms a uniform polymer layer.

<Titanium oxide layer formed on the outer wall of the magnetic core having the polymer layer formed>

[Example 7]

1 g of the core particle powder coated with the washed polymer layer, 1 ml of TBOT (tetrabuthoxy titanium) (Aldrich), and 1 ml of distilled water were charged with 170 ml of ethanol, followed by stirring at a rotational speed of 300 rpm for 2 hours at a temperature of 85 ° C. The titanium oxide layer was coated on the surface of the core particle powder coated with the polymer layer. The titanium oxide-coated core particle powder was separated by a magnet, washed twice with ethanol, and dried.

[Example 8]

1 g of the core particle powder coated with the washed polymer layer, 1 ml of TBOT (tetrabuthoxy titanium) (Aldrich), and 1 ml of distilled water were added to 170 ml of ethanol, followed by stirring at a rotational speed of 300 rpm for 2 hours at room temperature. The core particle powder was separated by a magnet, washed twice with ethanol and dried. The thickness of the titanium oxide layer according to the reaction temperature was measured using a transmission electron microscope (FEI, model name Tecnai G2 F30), and the results are shown in Table 3 below.

Example 7 Example 8 Reaction temperature 85 ℃ Room temperature Thickness of titanium oxide layer 70-100 nm 10 nm or less (nonuniform)

<Remove polymer layer to form hollow part>

[Example 9]

1 g of the core particles coated with the polymer layer and the titanium oxide layer were treated with a mixed solvent of acetone, distilled water and THF for 2 hours to form a magnetic core / pore (hollow part) / titanium oxide layer from which the polymer was removed. Magnetic particles were obtained.

The gap thickness was 15 nm.

[Example 10]

1 g of the core layer coated with the polymer layer and the titanium oxide layer prepared were calcined at 400 ° C. for 2 hours to remove the polymer, and the magnetic particles including the magnetic core / void portion (hollow portion) / titanium oxide layer were removed. Got it.

The gap thickness was 15 nm.

The removal of the polymer layer to form the hollow part can be confirmed from the presence or absence of the characteristic peaks (697nm, 753nm) of polystyrene using FT-IR (Thermo, Nicollet).

<Silver layer formed on the outer wall of the magnetic core with a hollow formed>

[Example 11]

4.5 g of glucose, 0.4 g of tartaric acid, and 10 ml of ethanol were dissolved with respect to 100 ml of distilled water, which was maintained at room temperature for 7 days to prepare a reducing solution. 50 ml of distilled water, 0.030 g of sodium hydroxide (SAMCHUN CHEMICAL), 0.7 ml of ammonia water (Fluka), and 0.28 g of silver nitrate (INUISHO) were mixed to prepare a colorless transparent silver rock adsorbent solution.

0.3 g of the core particle powder having the titanium oxide layer including the pores prepared in the above process was suspended in the silver ammonium complex solution, 10 ml of the reducing solution was mixed while ultrasonically irradiating the suspension, and stirring was continued for 20 minutes. The silver layer was coated.

The thickness of the silver layer was 70 nm.

Example 12-14

50 ml of distilled water, 0.030 g of sodium hydroxide (SAMCHUN CHEMICAL), 0.7 ml of ammonia water (Fluka), and 0.28 g of silver nitrate (INUISHO) were mixed to prepare a colorless transparent silver rock adsorbent solution.

0.3 g of the core particle powder having a titanium oxide layer having pores prepared in the process was suspended in a silver ammonia complex solution, and each reducing solution as shown in the following Table 4 was mixed while ultrasonically irradiating the suspension, and 20 Stirring was continued for minutes to coat the silver layer.

 The thickness of the silver layer was 70 nm.

Example 12 Example 13 Example 14 Reducing solution Polyvinyl pyrrolidone (Aldrich) Trisodium citrate (Aldrich) polyethylene imine (Aldrich)

Example 15-17

4.5 g of glucose, 0.4 g of tartaric acid, and 10 ml of ethanol were dissolved with respect to 100 ml of distilled water, which was maintained at room temperature for 7 days to prepare a reducing solution. 50 ml of distilled water, 0.030 g of sodium hydroxide (SAMCHUN CHEMICAL), 0.7 ml of ammonia water (Fluka), and 0.28 g of silver nitrate (INUISHO) were mixed to prepare a colorless transparent silver rock adsorbent solution.

0.3 g of the core particle powder having a titanium oxide layer having pores prepared in the above-mentioned process was suspended in a silver ammonia complex solution, and a reducing solution such as Example 15-17 was mixed while irradiating the suspension with ultrasonic waves, and for 20 minutes Stirring was continued to coat the silver layer.

 The thickness of the silver layer in each example was 60, 65 and 63 nm, respectively.

Example 15 Example 16 Example 17
Reducing solution
Glucose reducing liquid
+
Polyvinyl pyrrolidone
(Aldrich)
Glucose reducing liquid
+
Trisodium citrate
(Aldrich)
Glucose reducing liquid
+
polyethylene imine
(Aldrich)


Experimental Example 1

The magnetic particles including the silver layer obtained according to the above embodiments were evaluated based on the lightness measurement results of L, a, and b values of the color difference meter, and as a result, the brightness was 65 or more.

In addition, the oil absorption amount of the magnetic particles obtained according to the present invention was measured to compare the oil absorption with the magnetic substance itself and the pale magnetic substance having no voids.

Oil absorption measurement was carried out by a general test method for measuring the oil absorption of pigments and extender pigments as part of the Korean Industrial Standard KS M ISO 787 standard.

Oil absorption value is the amount of refined flaxseed that is absorbed in a pigment or sieving pigment sample under defined conditions and expresses the amount of oil in grams per 100g of sample.

[Measurement experiment of oil absorption]

The test sample was placed on a plate and slowly added 4 or 5 drops of linseed oil at a time using a burette. Each time you add oil, use a pallet knife to thoroughly mix the sample and oil. Continue to add oil at the same rate so that the oil and matter will clump. Once the mass is formed, add oil one drop at a time and rub it with a palette knife. Add oil until the batter is evenly beaten. This dough should spread directly onto the plate without cracking or crumbling, and should be adhering immediately.

Table 6 shows the results of the measured oil absorption.

Sample volume (g) Amount of oil used (g) Oil absorption (g / 100g) Fe
(BASF 025)
20.10 1.86 9.25
Fe / TiO 2 / Ag
(Product of Nittetsu company)
1.02 0.13 12.75
Magnetic material including voids 1.08 0.16 14.81

According to the results of Table 6, it can be seen that the oil absorption amount is improved in the case of the magnetic body including the continuous void portion, that is, the hollow portion formed between the core and the shell according to the present invention, whereby the magnetic particles of the present invention are incorporated into the ink composition. It can be expected that the compatibility can be improved, the viscosity control is easy, the printability can be improved, and the thixotropy can be improved.

[Example 18]

As an example of the host-guest material, Erbium oxide, Yttrium oxide, and ammonium metha vanadate are employed, and the materials are dissolved in dilute nitric acid at 2 molar concentration for one day and then citric acid. This was added to a 1: 7 volumetric solution of dissolved water and ethanol. After stirring vigorously for 1 hour to give sufficient viscosity, the magnetic particles obtained from Examples 11 to 17 were slowly added. After the reaction mixture was reacted for 3 hours with sufficient stirring to allow sufficient sol-gel reaction, the reaction solution was separated using a magnet, dried under vacuum at 150 ° C., heated at a rate of 1 ° C. per minute, and heat-treated in air at 700 ° C. A magnetic particle was prepared, including a magnetic core / void portion / titanium oxide layer / silver layer / light emitting layer composed of (YVO 4 : Er).

The magnetic particles obtained as described above are magnetic materials having magnetic properties and having incident light in the visible light region and light colored magnetic bodies emitting light in the 1500-1600 nm region.

[Example 19]

A magnetic material was manufactured in the same manner as in Example 18, except that Europium oxide, Yttrium oxide, and ammonium meta vanadate were used as host-guest materials for forming the emission layer. / Titanium oxide layer / silver layer / (YVO 4 : Eu) light emitting layer "

The magnetic particles thus obtained have magnetic properties and are light colored magnetic bodies that emit incident light in the ultraviolet region and emit light in the region of 600 to 650 nm.

[Example 20]

A magnetic material was manufactured in the same manner as in Example 18, except that neodymium oxide, yttrium oxide, and ammonium metavanadate were used as host-guest materials for forming the emission layer. Magnetic particles including " titanium oxide layer / silver layer / (light emitting layer) of (YVO 4 : Nd) &quot;.

The magnetic particles obtained as described above are magnetic materials having magnetic properties and having incident light in the visible light region and light colored magnetic bodies emitting light in the region of 1000 to 1100 nm.

Example 21

A magnetic material was manufactured in the same manner as in Example 18, except that the magnetic core / pore part was employed by employing holmium oxide, yttrium oxide, and ammonium metavanadate as a host-guest material for forming a light emitting layer. / Titanium oxide layer / silver layer / (YVO 4 : Ho) light emitting layer "

The magnetic particles obtained as described above are magnetic materials having magnetic properties, incident light rays in the ultraviolet region, and light colored magnetic bodies emitting light in the region of 500 to 600 nm.

[Example 22]

A magnetic material was manufactured in the same manner as in Example 18, except that Thulium oxide, Yttrium oxide, and ammonium meta vanadate were used as host-guest materials for forming the emission layer. / Titanium oxide layer / silver layer / (YVO 4 : Tm) light emitting layer "

The magnetic particles obtained as described above are magnetic materials having magnetic properties, incident light in the ultraviolet region, and light colored magnetic bodies emitting light in the region of 400 to 500 nm.

[Example 23]

1 g of iron powder (BASF 025, "core particles") having an average diameter of 1 μm and 2 g of PEI (polyethylene imine) (Aldrich) were mixed in 300 ml of distilled water, followed by 2 hours at a temperature of 25 ° C. Stirred at a rotational speed of 300 rpm, the core particle surface was treated with PEI. PEI treated core particle powder was separated by a magnet, washed twice with distilled water, and dried.

1 g of PEI-coated core particles and 0.3 g of spherical polystyrene particles (manufactured by hand) having an average diameter of 150 nm were added to 300 ml of distilled water, followed by a rotation speed of 300 rpm for 3 hours at a temperature of 25 ° C. By stirring, a core particle coated with polystyrene particles was prepared. The core particles coated with polystyrene particles were separated by a magnet, washed once with distilled water, and heat-treated at 106 ° C.

1 g of polystyrene-coated core particles, 3 ml of distilled water, and 1 ml of TBOT (tetrabuthoxy titanium) (Aldrich) were added with 330 ml of ethanol, and stirred at a rotational speed of 300 rpm for 3 hours at a temperature of 25 ° C. Titanium oxide was coated on the surface of the polystyrene particles coated core particles. The titanium oxide coated core particles were separated by a magnet, washed twice with ethanol, and dried.

1 g of the polystyrene particles and the titanium oxide layer-coated core particles were heat-treated at 400 ° C. for 2 hours in a nitrogen atmosphere, and thermally decomposed polystyrene particles from the core particles to form pores having a diameter of 150 nm uniformly. Magnetic particles in which a titanium oxide layer having parts were formed were prepared.

  [Example 24]

1 g of iron powder (BASF 025, "core particles") having an average diameter of 1 μm and 2 g of PEI (polyethylene imine) (Aldrich) were mixed in 300 ml of distilled water, followed by 2 hours at a temperature of 25 ° C. Stirred at a rotational speed of 300 rpm, the core particle surface was treated with PEI. PEI treated core particles were separated by a magnet, washed twice with distilled water, and dried.

1 g of PEI-coated core particles and 0.3 g of spherical polystyrene particles (manufactured by hand) having an average diameter of 150 nm were added to 300 ml of distilled water, followed by a rotation speed of 300 rpm for 3 hours at a temperature of 25 ° C. By stirring, a core particle coated with polystyrene particles was prepared. The core particles coated with polystyrene particles were separated by a magnet, washed once with distilled water, and dried without heat treatment at 106 ° C.

1 g of polystyrene-coated core particles, 3 ml of distilled water, and 1 ml of TBOT (tetrabuthoxy titanium) (Aldrich) were added with 330 ml of ethanol, and stirred at a rotational speed of 300 rpm for 3 hours at a temperature of 25 ° C. Titanium oxide was coated on the surface of the polystyrene particles coated core particles. The titanium oxide coated core particles were separated by a magnet, washed twice with ethanol, and dried.

The titanium oxide-coated core particles obtained in Examples 23 and 24 were observed with a transmission electron microscope (manufactured by FEI, model name Tecnai G2 F30 ) to obtain the results as shown in Table 7.

Example 23 Example 24 Heat treatment at 106 ℃ practice Absenteeism Observation Polystyrene Particles Fill Core Particle Powder Surface Only a few polystyrene particles are attached to the core particle powder surface

Thereafter, 1 g of the polystyrene particles and the core particles coated with the titanium oxide layer were heat-treated at 400 ° C. for 2 hours in a nitrogen atmosphere, and the polystyrene particles were thermally decomposed to remove the particles, thereby uniformly forming pores having a diameter of 150 nm. Magnetic particles having a titanium oxide layer having voids were formed.

  Example 25-26

1 g of iron powder (BASF 025, "core particles") with an average diameter of 1 μm in 250 ml of ethanol, 3.5 ml of distilled water, 0.3 g of spherical polystyrene particles having an average diameter of 100-300 nm (manufactured and used directly) ) Was mixed and then stirred at a rotational speed of 300 rpm for 2 hours at a temperature of 80 ° C. to coat the polystyrene particles and the titanium oxide layer on the surface of the core particles.

In this case, Example 25 used a polystyrene particle having a size of 150nm, and Example 26 used a 270nm.

1 g of the polystyrene particles and the titanium oxide layer-coated core particles were heat-treated at 400 ° C. for 2 hours in a nitrogen atmosphere, and the polystyrene particles were thermally decomposed and removed from the core particles to uniformly form pores having a thickness of 100-300 nm. Magnetic particles having a titanium oxide layer having voids were formed.

  [Example 27]

1 g of iron powder (BASF 025, "core particles") having an average diameter of 1 μm in 250 ml of ethanol, 3.5 ml of distilled water, and 0.3 g of spherical polystyrene particles having an average diameter of 270 nm (manufactured and used directly) After mixing, the mixture was stirred at a rotational speed of 300 rpm for 2 hours at a temperature of 80 ° C. to coat the polystyrene particles and the titanium oxide layer on the surface of the core particles.

1 g of the polystyrene particles and the core particles coated with the titanium oxide layer were heat-treated at 400 ° C. for 2 hours in a nitrogen atmosphere, and thermally decomposed to remove the polystyrene particles from the core particles, thereby uniformly forming pores having a diameter of 270 nm. Magnetic particles having a structure of a titanium oxide shell having voids were prepared.

  [Example 28]

Instead of heat treating the polystyrene particles prepared in Example 23 and the core particles coated with the titanium oxide layer, 1 g of the polystyrene particles prepared and the core particles coated with the titanium oxide layer were mixed with acetone, distilled water, and THF for 2 hours. Except that the polymer is removed by the treatment method, it can be carried out in the same manner as in Example 1 to obtain a magnetic particle having a shell including a pore portion in which a plurality of pores are formed in the magnetic core.

The removal of the polymer layer to form the hollow part can be confirmed from the presence or absence of a characteristic peak of polystyrene using FT-IR (Thermo, Nicollet).

 [Example 29]

     4.5 g of glucose, 0.4 g of tartaric acid, and 10 ml of ethanol were dissolved with respect to 100 ml of distilled water, which was maintained at room temperature for 7 days to prepare a reducing solution. 50 ml of distilled water, 0.030 g of sodium hydroxide (SAMCHUN CHEMICAL), 0.7 ml of ammonia water (Fluka), and 0.28 g of silver nitrate (INUISHO) were mixed to prepare a colorless transparent silver rock adsorbent solution.

0.3 g of magnetic particles containing a shell having pores formed with a plurality of pores in the magnetic core obtained from Examples 23 to 28 were suspended in a silver ammonia complex solution, and 10 ml of the reducing solution was mixed while irradiating ultrasonic waves to the suspension. The stirring was continued for 20 minutes to coat the silver layer. The thickness of the silver layer was 70 nm.

Example 30-32

      50 ml of distilled water, 0.030 g of sodium hydroxide (SAMCHUN CHEMICAL), 0.7 ml of ammonia water (Fluka), and 0.28 g of silver nitrate (INUISHO) were mixed to prepare a colorless transparent silver rock adsorbent solution.

0.3 g of magnetic particles comprising a shell having pores formed with a plurality of pores in the magnetic core obtained in Examples 23 to 28 were suspended in a silver ammonium complex solution, and the suspension was irradiated with ultrasonic waves, The reducing solution was mixed and stirring was continued for 20 minutes to coat the silver layer. The thickness of the silver layer was 65 nm, 70 nm, and 65 nm, respectively.

Example 30 Example 31 Example 32 Reducing solution Polyvinyl pyrrolidone
(Aldrich)
Trisodium citrate
(Aldrich)
polyethylene imine
(Aldrich)

Example 33-35

     4.5 g of glucose, 0.4 g of tartaric acid, and 10 ml of ethanol were dissolved with respect to 100 ml of distilled water, which was maintained at room temperature for 7 days to prepare a reducing solution. 50 ml of distilled water, 0.030 g of sodium hydroxide (SAMCHUN CHEMICAL), 0.7 ml of ammonia water (Fluka), and 0.28 g of silver nitrate (INUISHO) were mixed to prepare a colorless transparent silver rock adsorbent solution.

0.3 g of magnetic particles comprising a shell having pores formed with a plurality of pores in the magnetic core obtained from Examples 23 to 28 were suspended in a silver ammonia complex solution, and the suspension was irradiated with ultrasonic waves, respectively, as shown in Table 9 below. The reducing solution was mixed and stirring was continued for 20 minutes to coat the silver layer. The thickness of the silver layer was 70 nm, 75 nm, and 65 nm, respectively.

Example 33 Example 34 Example 35 Reducing solution Glucose reducing liquid
+
Polyvinyl pyrrolidone (Aldrich)
Glucose reducing liquid
+
Trisodium citrate (Aldrich)
Glucose reducing liquid
+
polyethylene imine (Aldrich)

Experimental Example 2

For the magnetic particles obtained in Examples 29 to 35, the brightness was evaluated by the lightness measurement results by the L, a, and b values of the color difference meter, and as a result, the brightness was 65 or more.

In addition, the oil absorption amount was measured for comparing the oil absorption amount with the magnetic substance itself and the pale magnetic substance which does not have many void parts about the magnetic particle obtained by this invention.

Oil absorption measurement was carried out by a general test method for measuring the oil absorption of pigments and extender pigments as part of the Korean Industrial Standard KS M ISO 787 standard.

Oil absorption value is the amount of refined flaxseed that is absorbed in a pigment or sieving pigment sample under defined conditions and expresses the amount of oil in grams per 100g of sample.

[Measurement experiment of oil absorption]

The test sample was placed on a plate and slowly added 4 or 5 drops of linseed oil at a time using a burette. Each time you add oil, use a pallet knife to thoroughly mix the sample and oil. Continue to add oil at the same rate so that the oil and matter will clump. Once the mass is formed, add oil one drop at a time and rub it with a palette knife. Add oil until the batter is evenly beaten. This dough should spread directly onto the plate without cracking or crumbling, and should be adhering immediately.

Table 10 shows the results of the measured oil absorption.

Sample volume (g) Amount of oil used (g) Oil absorption (g / 100g) Fe
(BASF 025)
20.10 1.86 9.25
Fe @ TiO2 @ Ag
(Nittetsu company)
1.02 0.13 12.75
Porous Magnetic Particles 0.87 0.18 20.11

According to the results of Table 10, it can be seen that the oil absorption amount is improved in the case of the magnetic particles including the discontinuous pores formed in the shell, that is, the shell in which the plurality of pores are formed, according to the present invention, thereby inking the magnetic particles of the present invention. When blended into the composition, it can be expected that the compatibility can be improved, the viscosity control is easy, the printability can be improved, and the thixotropy can be improved.

[Example 36]

Examples of host-guest materials include Erbium oxide, Yttrium oxide, and ammomium metha vanadate, and the materials are dissolved in dilute nitric acid at 2 molar concentration for one day and then citric acid. This was added to a 1: 7 volumetric solution of dissolved water and ethanol. After vigorous stirring for 1 hour to give sufficient viscosity, the magnetic particles obtained from Examples 29 to 35 were slowly added. After the reaction mixture was reacted for 3 hours with sufficient stirring to allow sufficient sol-gel reaction, the reaction solution was separated using a magnet, dried under vacuum at 150 ° C., heated at a rate of 1 ° C. per minute, and heat-treated in air at 700 ° C. A magnetic particle comprising a "titanium oxide layer / silver layer / (YVO 4 : Er) comprising a magnetic core / pore part" is manufactured.

The magnetic particles obtained as described above are magnetic materials having magnetic properties and having incident light in the visible light region and light colored magnetic bodies emitting light in the 1500-1600 nm region.

[Example 37]

A magnetic material was manufactured in the same manner as in Example 36, except that Europium oxide, Yttrium oxide, and ammonium meta vanadate were used as host-guest materials for forming the emission layer. A magnetic particle comprising a "light emitting layer made of titanium oxide layer / silver layer / (YVO 4 : Eu)" was prepared.

The magnetic particles thus obtained have magnetic properties and are light colored magnetic bodies that emit incident light in the ultraviolet region and emit light in the region of 600 to 650 nm.

[Example 38]

A magnetic material was manufactured in the same manner as in Example 36, except that neodymium oxide, yttrium oxide, and ammonium metavanadate were used as host-guest materials for forming the emission layer. A magnetic particle comprising a "light emitting layer made of titanium oxide layer / silver layer / (YVO 4 : Nd) containing".

The magnetic particles obtained as described above are magnetic materials having magnetic properties and having incident light in the visible light region and light colored magnetic bodies emitting light in the region of 1000 to 1100 nm.

[Example 39]

A magnetic material was prepared in the same manner as in Example 36, except that the magnetic core / pore part was employed by employing holmium oxide, yttrium oxide and ammonium metavanadate as a host-guest material for forming the light emitting layer. A magnetic particle comprising a "light emitting layer comprising titanium oxide layer / silver layer / (YVO 4 : Ho)” was prepared.

The magnetic particles obtained as described above are magnetic materials having magnetic properties, incident light rays in the ultraviolet region, and light colored magnetic bodies emitting light in the region of 500 to 600 nm.

[Example 40]

A magnetic material was prepared in the same manner as in Example 36, except that Thulium oxide, Yttrium oxide, and ammonium metavanadate were used as host-guest materials for forming the light emitting layer. A magnetic particle comprising a titanium oxide layer, a silver layer, and a light emitting layer composed of (YVO 4 : Tm).

The magnetic particles obtained as described above are magnetic materials having magnetic properties, incident light in the ultraviolet region, and light colored magnetic bodies emitting light in the region of 400 to 500 nm.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, Those skilled in the art will recognize that many modifications and variations are possible in light of the above teachings.

Accordingly, the spirit of the present invention should not be construed as being limited to the embodiments described, and all of the equivalents or equivalents of the claims, as well as the following claims, belong to the scope of the present invention .

Claims (31)

A magnetic core and a shell, the continuous or discontinuous pores formed between the core and the shell or in the shell, the gap or diameter of the pores being at least 10 nm;
Magnetic particles comprising an inorganic light emitting layer.
The method of claim 1,
The inorganic light emitting layer is at least one host material selected from the group consisting of erbium, europium, ytterbium, holium, and thulium, and at least one selected from the group consisting of yttrium, gadolinium, vanadium, zinc, titanium, and oxides thereof A magnetic particle comprising a compound having a host: guest combination comprising a guest of.
The magnetic particle of claim 2 comprising a compound having a host: guest combination that is YVO 4 : Eu, YVO 4 : Er, YVO 4 : Nd, YVO 4 : Ho, YVO 4 : Tm. The method of claim 1,
The light emitting layer is magnetic particles formed on at least one shell.
3. The method according to claim 1 or 2,
The light emitting layer is a magnetic particle that is a laminated film of a plurality of light emitting layers that absorb light of different wavelengths and emit light of different wavelengths.
The method of claim 1,
Magnetic particles comprising a continuous void formed between the core and the shell, wherein the gap of the void is at least 10 nm.
The method of claim 1,
Magnetic particles comprising discontinuous pores formed in the shell, wherein the pores forming the pores are at least 50 nm in diameter.
The magnetic particle of claim 1, wherein the shell comprises a dielectric material or a metal. 8. The method of claim 1 or 7,
On at least one layer of dielectric shell of dielectric material comprising voids,
Magnetic particles comprising at least one metal shell made of a metal.
The method of claim 5, wherein
The pores are magnetic particles having hollow portions having a gap of 10 to 300 nm.
The method according to claim 6,
The pores are pores with pores having a diameter of 50 to 300 nm.
The method of claim 1,
Magnetic particles with brightness greater than 65.
The method of claim 1,
Magnetic particles, characterized in that the security particles of the deed.
Applying a plurality of particles or materials for forming voids on the magnetic core to be a material which is removable by firing or chemical treatment at high temperature;
Forming a shell comprising a dielectric material or a metal on the particles obtained from the previous step;
Removing a plurality of particles or materials for forming the voids to form a shell including the voids; And
Method for producing a magnetic particle comprising the step of forming an inorganic light emitting layer.
15. The method of claim 14,
Forming a metal shell comprising a metal on a shell comprising a void portion manufacturing method of magnetic particles.
15. The method of claim 14,
The step of applying the material for forming the pore portion is performed by a method of polymerizing the polymer forming composition on the magnetic core, and the polymer forming composition comprises a raw material monomer and an initiator for preparing a polymer. .
17. The method of claim 16,
Forming the material layer for forming the voids is a method of producing a magnetic particle is carried out by the method of surface-modifying the magnetic core using a coupling agent, and polymerizing the polymer forming composition on the surface-modified magnetic core.
17. The method of claim 16,
The composition for forming a polymer is a method for producing magnetic particles containing an anionic monomer as a coagulation stabilizer.
The method of claim 18,
A method for producing magnetic particles in which the thickness of the gap portion is controlled according to the content of the raw material monomer and the anionic monomer in the polymer-forming composition.
17. The method of claim 16,
The composition for forming a polymer comprises a styrene-based monomer as a raw material monomer, and a method for producing magnetic particles comprising sodium styrene sulfonate as an anionic monomer.
The method of claim 17,
Surface modification in the step of applying the material for forming the pore portion is a method for producing magnetic particles is carried out using 3-methacryloxy propyl trimethoxysilane as a coupling agent.
15. The method of claim 14,
The applying of the plurality of particles for forming the voids comprises mixing and stirring the magnetic core and the particles for forming the voids in a solvent, and performing the heat treatment of the magnetic particles coated with the separated void forming particles. Manufacturing method.
23. The method of claim 22,
Heat treatment is a method for producing magnetic particles carried out in a temperature range of 100 to 110 ℃.
23. The method of claim 22,
The method for producing magnetic particles, wherein the pore forming particles are vinyl polymer particles having a size of 50 to 300 nm.
23. The method of claim 22,
Core is coated with polyethylene imine to produce surface-modified magnetic particles.
15. The method of claim 14,
Forming the shell having the voids is a method of producing magnetic particles is carried out by the method for removing the magnetic particles obtained from the previous step by removing the particles for forming the voids or a solvent for dissolving the substance.
15. The method of claim 14,
Forming the shell having a void portion is a method for producing magnetic particles is carried out by firing the magnetic particles obtained from the previous step in a temperature range capable of firing the material for forming the void portion.
15. The method of claim 14,
Forming the inorganic light emitting layer is a method for producing magnetic particles is carried out through a sol-gel reaction by dispersing the magnetic particles obtained from the previous step in a composition comprising a host-guest material and a chelate structure generating agent.
Magnetic particles obtained according to the method of claim 14. The security ink of the oil price certificate containing the magnetic particle of Claim 1. The security ink of the oil price certificate containing the magnetic particle of Claim 29.
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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20190091149A (en) 2018-01-26 2019-08-05 공주대학교 산학협력단 Fe-Cr-Co-X system Alloy Powder for Counterfeit Prevention, and Method for Manufacturing The Same
EP3886124A4 (en) * 2019-07-29 2022-08-24 Korea Minting, Security Printing & ID Card Operating Corp. Magnetic particle for security ink and security ink comprising same

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101718505B1 (en) * 2015-12-29 2017-03-22 한국조폐공사 Method of manufacturing of magnetic particle for security ink and security ink using the same

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2000148156A (en) 1998-11-05 2000-05-26 Hiroshi Yamada Bell structured particle, its manufacture, and vibration absorber
KR20050018200A (en) * 2003-08-14 2005-02-23 한남대학교 산학협력단 HCMS capsule structures containing metal nanoparticles within the hollow core, and their preparation method
JP2008284411A (en) 2007-05-15 2008-11-27 Osaka Univ Photocatalyst included in hollow porous shell layer and its manufacturing method
KR100975427B1 (en) 2009-10-30 2010-08-12 한국화학연구원 Preparation of mesoporous hollow core-shell particles

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2000148156A (en) 1998-11-05 2000-05-26 Hiroshi Yamada Bell structured particle, its manufacture, and vibration absorber
KR20050018200A (en) * 2003-08-14 2005-02-23 한남대학교 산학협력단 HCMS capsule structures containing metal nanoparticles within the hollow core, and their preparation method
JP2008284411A (en) 2007-05-15 2008-11-27 Osaka Univ Photocatalyst included in hollow porous shell layer and its manufacturing method
KR100975427B1 (en) 2009-10-30 2010-08-12 한국화학연구원 Preparation of mesoporous hollow core-shell particles

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20190091149A (en) 2018-01-26 2019-08-05 공주대학교 산학협력단 Fe-Cr-Co-X system Alloy Powder for Counterfeit Prevention, and Method for Manufacturing The Same
EP3886124A4 (en) * 2019-07-29 2022-08-24 Korea Minting, Security Printing & ID Card Operating Corp. Magnetic particle for security ink and security ink comprising same

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