JP2000178553A - Fluorescent pigment composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a composition which is useful for color printing, as an ink for coating and the like having a beautiful and stable color tone of a single color such as blue, green, yellow or the like and renders it possible to discriminate a real printed matter or the like from a false one by the irradiation indoors with a light source such as a fluorescent lamp and the like and therefore is useful for the prevention of forgery by compounding a multilayered film-coated powder comprising a substrate particle and plural coating films thereon and a fluorescent substance. SOLUTION: This composition can be colored with the interference colors by covering a substrate particle with layers, each having a refractive index and a layer thickness suitably chosen, using plural coating layers having a different refractive index from one another. As materials for a substrate particle can be employed those having various characteristics such as magnetism, ferroelectricity, electroconductivity or the like and there can be exemplified metals, metal compounds, organic matters, inorganic matters and the like. Preferably the materials to constitute each coating layer are selected optionally among inorganic metal compounds, metals and alloys, and organic matters. A fluorescent substance is not particularly limited provided that it emits easily distinguishable fluorescence by the irradiation with ultraviolet rays or visible rays.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluorescent pigment composition, and more particularly to a fluorescent pigment composition, which has both color and fluorescent properties, and is used to prevent forgery when used as inks, fillers, paints and toners for printing and coating. It relates to a useful fluorescent pigment composition.

[0002]

2. Description of the Related Art It is known that by coating the surface of a powder with a film of another substance, the properties of the powder can be improved or its properties can be varied. Means have been proposed. For example, coating techniques for forming a film on the surface of an object for protection or decoration include coating methods,
Many means are known, such as deposition, sputtering, vacuum deposition, electrodeposition and anodic oxidation. However, it is difficult to make the thickness of the film uniform by the coating method or the deposition method, and it is difficult to obtain a thick film by the sputtering or the vacuum evaporation method. In addition, the electrodeposition method and the anodic oxidation method have a problem that they are not suitable for powder processing because the object to be processed is used as an electrode. With the progress in various technical fields, there is an increasing demand for powders having unique properties, particularly metal powders or metal compound powders. There is a demand for a powder having combined properties with other properties in addition to the provided properties. For example, in the raw magnetic powder of the color magnetic toner, the color of the magnetic metal powder, which has not been a problem in the conventional black magnetic toner, cannot be used as it is. Form a thin metal oxide film on the surface of the powder to protect the powder, or to modify the surface to make it easier to mix with synthetic resin, etc. The means of doing so cannot withstand the new demands of this field. In this respect, it is necessary to provide a powder having a new composition not found in conventional powders.

[0003] A useful method of forming a metal oxide for providing a powder having a composite property meeting the above-mentioned new requirements and capable of fulfilling a composite function, particularly a metal or metal compound powder. First, the present inventors,
A metal powder or a metal oxide powder is dispersed in a metal alkoxide solution, and the metal alkoxide is hydrolyzed to form a metal oxide film. .01-20 μm thick,
A powder having a metal oxide film containing a metal different from the metal constituting the base has been invented (JP-A-6-228).
604).

In this powder, when a plurality of metal oxide films are provided, a special function can be given by adjusting the thickness of each layer of the metal oxide film. On the surface of the coating film with different refractive index,
If the light is provided with a thickness corresponding to a quarter wavelength of light, all light is reflected. This means iron, cobalt,
When applied to a magnetic substance such as a metal powder such as nickel, a metal alloy powder, or an iron nitride powder, a magnetic powder for a magnetic toner that shines white by totally reflecting light can be obtained. . Further, it discloses that a color magnetic toner can be obtained by providing a colored layer on the powder and a resin layer thereon (Japanese Patent Application Laid-Open No. 7-90310).

Further, the present inventors have found that the reflected light interference waveform of the multilayer film can be adjusted by controlling the combination of the materials and the film thickness of the multilayer film. It has been disclosed to provide a multilayer-coated powder having a stable color tone (WO96 / 282).
69).

As described above, the present inventors have formed a metal oxide or metal coating on the surface of a metal powder or a metal compound powder, and have a property that the metal or metal compound powder to be a base is provided. In addition to these, efforts have been made to develop highly functional metal or metal compound powders by imparting other properties. In the case of color printing and color magnetic printing of gift certificates and ticket cards, which have been growing in demand in recent years, in addition to the elegance of coloring, special functions for preventing forgery are required in addition to visual and magnetic reading. ing. In response to this trend, by adjusting the reflected light interference waveform of the multilayer film described above, inks with beautiful and stable colors such as blue, green, and yellow can be obtained without using dyes and pigments, and in the visible light range. In addition, the color has a function that can enhance the anti-counterfeiting performance of printed matter by a method other than visual or magnetic reading by combining with a reader using reflected light by ultraviolet light or infrared light because it has an interference reflection peak. An ink composition was provided (JP-A-10-60350).

[0007]

However, in the above-described color ink composition, an inspection device is required to determine the authenticity by combining with a reader using reflected light by ultraviolet rays or infrared rays. . A function that can easily determine the authenticity and that can further enhance the forgery prevention performance of printed matter by a new method is essential,
There was room for improvement. Accordingly, an object of the present invention is to solve these problems, and to provide a beautiful and stable color print of a single color such as blue, green, and yellow, a coating ink, a filler, a paint and a high-performance color magnetic print. It is useful as an ink, and can be authenticated by a simple method such as irradiating a light source such as a fluorescent lamp, an ultraviolet lamp, or an infrared lamp indoors without using any new inspection equipment. It is an object of the present invention to provide a fluorescent pigment composition having a function of further improving anti-counterfeiting performance.

[0008]

Means for Solving the Problems As a result of intensive studies, the present inventors have formed a multilayer thin film having a different refractive index on the surface of a powder, and adjusted the reflected light interference waveform of the multilayer film. By mixing fluorescent fine particles that are the same or different from the color, it becomes a beautiful and stable color composition of blue, green, yellow, etc. even when used alone, and at the same time, distinguishes printed matter by the presence or absence of fluorescence It was found that forgery prevention became possible, and the present invention was completed. Also,
As the substrate of the powder, those having various properties such as a ferroelectric substance and a conductor can be used. Even when a magnetic substance is used as the substrate, the multilayer film-coated powder is vivid without impairing the magnetism. It has been found that coloring and fluorescence can be obtained.

That is, the present invention is as follows. (1) A fluorescent pigment composition comprising a multi-layer coating powder having a plurality of coating films on substrate particles and a fluorescent substance. (2) The fluorescent pigment composition according to the above (1), wherein the multilayer film exhibits a light interference effect. (3) The forgery-preventing fluorescent pigment composition according to (1), wherein the multilayer film exhibits a specific interference reflection peak in a region other than the visible light region. (4) The fluorescent pigment composition according to the above (1), wherein the base particles are magnetic particles. (5) The fluorescent pigment composition according to the above (1), further comprising a coloring material.

[0010] The fluorescent pigment composition of the present invention is, as described above,
It is useful as an ink, filler or paint for color printing and coating with fluorescence, and when a magnetic material is used as a substrate, it can be used as a coloring material for high-performance color magnetic printing inks, It has a discriminating function of six combinations of invisible light (ultraviolet and infrared), fluorescent coloring and magnetism, and electricity (electric field change), and can enhance the effect of preventing forgery of printed matter.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The substrate of the multilayer film-coated powder used in the present invention is not particularly limited, and powders having various properties such as magnetism, ferroelectricity and conductivity can be used. As the kind of the substance, a wide variety of substances such as a metal, a metal compound, an organic substance, and an inorganic substance can be used. Metals include iron, nickel, chromium, titanium,
Transition metals such as cobalt, copper and aluminum, metals such as rare earth metals such as neodymium and yttrium and alloys thereof, for example, alloys of the above-mentioned metals such as iron-nickel and iron-cobalt alloys, and also iron-nickel alloy nitrides and the like Examples of iron / nickel / cobalt alloy nitrides and metal oxides include oxides such as iron, nickel, chromium, titanium, aluminum and silicon (in this case, silicon is classified as metal), calcium, magnesium And alkaline earth metal oxides such as barium and the like or composite oxides thereof, clays, glasses and the like. In the present invention, one of the objects is to produce a powder that also shares magnetism such as a color magnetic toner or a color magnetic ink. It is preferable to use a ferromagnetic material as the substrate. The ferromagnetic material may be a transition metal such as iron, nickel, chromium, titanium, cobalt, copper, or aluminum, a rare earth metal such as neodymium or yttrium, or a metal having a high magnetic susceptibility such as an alloy of these metals. A ferromagnetic oxide or ferromagnetic alloy such as ferrite, Sr ferrite, γ-hematite, cobalt ferrite, or a mixed ferrite thereof is also used.

The organic substance is preferably resin particles. Specific examples thereof include cellulose powder, cellulose acetate powder, polyamide, epoxy resin, polyester, melamine resin, polyurethane, vinyl acetate resin, silicon resin, acrylic ester, Spherical or crushed particles obtained by polymerization or copolymerization of acrylic acid ester, styrene, ethylene, propylene and derivatives thereof. Particularly preferred resin particles are spherical acrylic resin particles obtained by polymerization of acrylic acid or methacrylic acid ester.

Further, inorganic substances include inorganic hollow particles such as shirasu balloons (hollow silicic acid particles), fine carbon hollow spheres (crecassphere), fused alumina bubbles, aerosil, white carbon, silica fine hollow spheres, calcium carbonate fine spheres. Hollow spheres, calcium carbonate, perlite, talc, bentonite, kaolin, mica, synthetic mica, glass beads and the like can be used. Examples of the shape of the powder core particles include polyhedrons such as spheres, subspheres, regular polyhedrons, and the like, rectangular parallelepipeds, spheroids, rhombohedrons, plate-like bodies, needle-like bodies (cylinders, prisms), and the like. It is also possible to use a completely amorphous powder such as an object. These substrates are not particularly limited in terms of particle size, but are usually 0.01 μm to several m.
m, preferably from 0.05 μm to 20 μm.
It is in the range of 0 μm.

In the present invention, a plurality of coating layers having different refractive indices are used, and the base particles are coated with the interference color by appropriately selecting the refractive index and the layer thickness of each coating layer. be able to. It is desirable that the material constituting each coating layer is arbitrarily selected from inorganic metal compounds, metals or alloys, and organic substances. Examples of the inorganic metal compound constituting the coating layer include metal oxides as typical examples, and specific examples include iron and iron.
Oxides such as nickel, chromium, titanium, aluminum, silicon, calcium, magnesium, barium, and the like, or composite oxides thereof are mentioned. Further, examples of the metal compound other than the metal oxide include metal nitrides such as magnesium fluoride and iron nitride, and metal carbides. As the simple metal constituting the coating layer, metallic silver, metallic cobalt, metallic nickel, metallic palladium, metallic iridium, platinum, gold, metallic iron, and the like are mentioned, and as the metallic alloy, silver-iridium, palladium-platinum, silver-palladium And alloys such as platinum-palladium.

The organic substance constituting the coating layer may be the same as or different from the above-mentioned organic substance constituting the substrate, and is not particularly limited, but is preferably a resin. Specific examples of the resin include cellulose, cellulose acetate, polyamide, epoxy resin, polyester, melamine resin, polyurethane, resin vinyl resin, silicon resin, acrylate, methacrylate, styrene,
Examples include polymers or copolymers of ethylene, propylene and derivatives thereof. As described above, various materials can be used as the material constituting the coating layer. However, it is necessary to appropriately select the combination of these materials according to the application in consideration of the refractive index of each coating layer. It is.
The particle size of the powder coated with the multilayer film according to the present invention is not particularly limited and can be appropriately adjusted depending on the purpose, but is usually in the range of 0.01 μm to several mm.

In the present invention, the thickness of the coating film formed at one time can be in the range of 5 nm to 10 μm, which can be made thicker than the conventional forming method. In the case of the color powder described above, the total thickness of the coating film formed in a plurality of times is 10 nm to 20 nm in order to form a coating film having a high reflectance due to the interference.
The range of μm is preferable, and more preferably 20 nm to 5 nm.
μm range. For interference reflection of visible light with a particularly thin film thickness, for example, when the particle size is limited, 0.02
It is preferable to set it in the range of 2.0 μm.

The thickness of each unit coating layer constituting the plurality of coating layers is set so as to have an interference reflection peak or an interference transmission bottom of a specific same wavelength. More preferably, the thickness of each unit coating layer is set by the following equation (1): N × d = m × λ / 4 (1) [where N is a complex refractive index, d is a basic thickness, and m is Integer (natural number), λ represents the wavelength of the interference reflection peak or the interference transmission bottom, and N is the following equation (2): N = n + iκ (2) (n is the refractive index of each unit coating layer, i is a complex number, κ Represents a damping coefficient)], and each unit is obtained from a function consisting of a phase shift due to a refractive index attenuation coefficient κ, a phase shift at a film interface, a dispersion of a refractive index, and a peak shift depending on a particle shape. The actual thickness of each unit coating layer is corrected so that the coating layer has the interference reflection peak or the interference transmission bottom of the specific wavelength.

As a method of forming the film, the following methods can be mentioned depending on the substance to be formed.
Other methods can also be used. (1) When forming an organic film (resin film) a. Polymerization Method in Liquid Phase A method of forming a resin film on the particles by dispersing the particles serving as the substrate and subjecting the particles to emulsion polymerization can be used. b. Film forming method in gas phase (CVD) (PVD) (2) When forming an inorganic metal compound film a. Solid phase deposition method in liquid phase A method of dispersing particles serving as a substrate in a metal alkoxide solution and hydrolyzing the metal alkoxide to form a metal oxide film on the particles is preferable, and a dense metal An oxide film can be formed. Further, a metal oxide film or the like can be formed on the particles by the reaction of the aqueous metal salt solution. b. Film forming method in gas phase (CVD) (PVD)

(3) When forming a metal film or an alloy film a. Method of Reducing Metal Salt in Liquid Phase A so-called chemical plating method of reducing a metal salt in an aqueous solution of a metal salt to deposit a metal to form a metal film is used. b. Film formation method in gas phase (CVD) (PVD) A metal film can be formed on the surface of particles by vacuum evaporation of metal or the like.

In the fluorescent pigment composition of the present invention, the fluorescent substance mixed with the powder coated with the multilayer film has a characteristic of emitting fluorescent light which can be easily distinguished by irradiating ultraviolet light or visible light. Is not particularly limited,
A fluorescent substance that can maintain the fluorescence coloring property for a long time is preferable. The function of a fluorescent substance is temporarily excited by electromagnetic waves (light) at a specific wavelength, and light of a specific wavelength (especially visible light)
Which does not emit light without a light source. The fluorescent substance is a fluorescent dye or a fluorescent pigment, which is a general term for a dye that absorbs external energy and emits fluorescence.In addition to the color of the dye itself, fluorescence of substantially the same wavelength is added, so It exhibits a color. For example, C.I. I.
Acid Yellow 7, a red basic dye that emits yellow to orange fluorescence. I. Basic Red and the like.

The following are specific examples of the fluorescent substance, but the present invention is not limited to these specific examples. Specifically, for example, organic fluorescent pigments include uranine, eosin, diaminotilbene, thioflavin T, rhodamine B, International Orange, and the like. As inorganic fluorescent pigments, calcium tungstate, lead-containing barium silicate, europium Contains strontium phosphate, europium-containing yttria, cerium-containing yttria, one or more of copper or silver, tin, manganese, arsenic, aluminum, and cadmium, zinc sulfide, manganese-containing magnesium gallate, magnesium fluoride, calcium fluoride, oxygen-deficient oxidation Zinc, europium-containing zinc oxide, cerium-containing zinc oxide, cesium-containing zinc oxide, manganese or arsenic-containing zinc silicate, bismuth-containing zinc cadmium, bismuth-containing calcium strontium sulfide, etc. And the like.

In the fluorescent pigment composition of the present invention, the relationship between the fluorescent substance and the above-mentioned powder coated with a multilayer film is as follows: 1) a form in which the powder is adhered to the surface of the powder coated with the multilayer film; It is used in a form in which the powder is dry-mixed and a fluorescent substance is attached to the surface of the multilayer-coated powder, and 3) in a form in which the multilayer-coated powder and the fluorescent substance are dispersed in a fluorescent pigment composition.

The mutual forms of the fluorescent substance and the powder coated with the multilayer film in the above 1), 2) and 3) include the following methods. 1) Multilayer-coated powder and fluorescent substance fine particles dispersed in a solvent (phosphor particles having a smaller particle size than the particles of the multi-layer coated powder)
And adhering them by heteroaggregation or the like. 2) Preparation is performed by dry mixing phosphor particles having a smaller particle size than the particles of the multilayer film-coated powder. In the case of the above two methods, it is desirable to subject these obtained powders to heat treatment if necessary. Further, in the case of the above two methods, it is desirable that the fluorescent substance having the multilayer film-coated powder adhered to the surface remains adhered. However, the fluorescent substance may be separated and dispersed in the fluorescent pigment composition.
However, among applications such as forgery prevention, it is more preferable that both are integrated in applications where it is essential to recognize the characteristics of the multilayer-coated powder particles and the characteristics of the fluorescent substance at the same position. Further, in order not to erase the color of the multilayer-coated powder, it is desirable that the powder is as white, transparent, white or nearly transparent as possible, or the same color as the multilayer-coated powder. However, this is not always the case when coloring is performed in different colors with the multilayer-coated powder and the fluorescent substance.

3) The method of dispersing the composition in which the multilayer-coated powder and the fluorescent substance are dispersed in the fluorescent pigment composition is described in the above 1) or 2). Used, as the dispersion medium, a conventionally known varnish used for color printing or color magnetic printing can be used, for example, a liquid polymer described later, a polymer or monomer dissolved in an organic solvent, a powder type or the like. The ink can be appropriately selected and used depending on the application method and application of the ink. In the fluorescent pigment composition dispersed in the dispersion medium of the above 3), the powder coated with the multilayer film and the fluorescent substance are separated and dispersed in the dispersion medium.

Next, as an example, a method for forming an alternate multilayer film of a metal oxide having a high refractive index and a metal oxide having a low refractive index will be specifically described. First, the base particles are dispersed in an alcohol solution in which an alkoxide such as titanium or zirconium is dissolved, and a mixed solution of water, alcohol, and a catalyst is dropped with stirring, and the alkoxide is hydrolyzed, so that the surface of the base particles is highly refracted. A titanium oxide film or a zirconium oxide film is formed as a rate film. Thereafter, the powder is subjected to solid-liquid separation, dried and then subjected to a heat treatment.
The drying means may be any of vacuum heating drying, vacuum drying, and natural drying. Further, it is also possible to use a device such as a spray dryer in an inert atmosphere while adjusting the atmosphere. In the heat treatment, a coating composition that does not oxidize is in the air, and a coating composition that is easily oxidized is in an inert atmosphere,
00 ° C (when the powder core particles are inorganic powder) or 150 to
1 minute at 500 ° C (when the powder core particles are other than inorganic powder)
Heat-treat for 3 hours. Then, silicon alkoxide, aluminum alkoxide, etc., in an alcohol solution in which a metal alkoxide having a low refractive index when converted to an oxide is dissolved, the powder having the high refractive index film is dispersed therein, while stirring. By dropping a mixed solution of water, alcohol and catalyst and hydrolyzing the alkoxide, a silicon oxide or aluminum oxide film is formed as a low refractive index film on the surface of the high refractive index film-coated powder. Thereafter, the powder is subjected to solid-liquid separation, dried under vacuum, and then subjected to heat treatment in the same manner as described above. By this operation, by repeating the operation of forming a two-layer, high-refractive-index metal oxide film on the surface of the powder base particles, a fluorescent multilayer film-coated powder having a multilayer metal oxide film is obtained. .

Further, a special function can be provided by adjusting the thickness of each layer of the alternating coating films having different refractive indexes formed on the surface of the base particles. For example, an alternating coating film having a different refractive index is provided on the surface of the base particles so that the refractive index n of the substance (unit coating layer) forming the coating film and the wavelength of visible light of 4 are satisfied so as to satisfy the following expression (3). An alternate film having a thickness d corresponding to an integer m times 1 / m is provided in an appropriate thickness and number. As a result, light of a specific wavelength λ (using the interference reflection of Fresnel) is reflected or absorbed. nd = mλ / 4 (3) By utilizing this action, a film having a film thickness and a refractive index that satisfies the formula (3) with respect to the target wavelength of visible light is formed on the surface of the base particle. By alternately repeating the coating of a film having a different refractive index once or more thereon, a film having a reflection or absorption wavelength width specific to the visible light region is formed. At this time, the order of the materials to be formed is determined as follows. First, when the refractive index of the base particles themselves is high, it is preferable that the first layer is a film having a low refractive index, and in the opposite case, the first layer is preferably a film having a high refractive index.

The change in the optical film thickness, which is the product of the film refractive index and the film thickness, is measured and controlled as a reflection waveform by a spectrophotometer or the like. The thickness of each layer is designed. For example, when the peak position of the reflection waveform of each unit coating constituting the multilayer film is shifted, white powder is obtained, but when the peak position of the reflection waveform of each unit coating is precisely adjusted, no dye or pigment is used. Both can be a single colored powder such as blue, green and yellow.

However, in the case of actual powder, the particle size of the powder,
It is necessary to design in consideration of the shape, the phase shift at the mutual interface between the film material and the nuclear particle material, the peak shift due to the wavelength dependence of the refractive index, and the like. For example, when the shape of the core particle is a parallel plate, the Fresnel interference by the parallel film formed on the particle plane is obtained by replacing n in the above equation (3) with the following equation (4).
The design is performed under the condition that N is replaced. In particular, when the metal film is included even when the shape of the powder is a parallel plate,
The damping coefficient κ is included in the refractive index N of the metal in the equation (4). In the case of a transparent oxide (dielectric), κ is very small and can be ignored. N = n + iκ (i represents a complex number) (4) If this damping coefficient κ is large, the phase shift at the mutual interface between the film material and the nuclear particle material becomes large, and all the layers of the multilayer film are caused by the phase shift. Affects the interference optimum film thickness.

As a result, even if only the geometrical film thickness is adjusted, the peak position is shifted, so that the color becomes lighter, especially when colored in a single color. In order to prevent this, the effects of the phase shift on all the films are taken into consideration, and a computer simulation is designed so that the combination of the film thicknesses is optimized in advance. Further, there is a phase shift due to the oxide layer on the metal surface and a peak shift due to the wavelength dependence of the refractive index. In order to correct these, it is necessary to find an optimum condition using a spectrophotometer or the like so that the reflection peak and the absorption bottom have the set wavelength in the final target film number.

The interference of a film formed on a curved surface such as a spherical powder occurs similarly to a flat plate, and basically follows the Fresnel interference principle. Therefore, the coloring method can be designed to be a single color. However, in the case of a curved surface, light incident on and reflected by the powder causes complicated interference. These interference waveforms are almost the same as a flat plate when the number of films is small. However, as the total number of films increases, the interference inside the multilayer film becomes more complicated. Also in the case of a multilayer film, the reflection spectral curve can be designed in advance by computer simulation based on the Fresnel interference so that the combination of the film thickness is optimized. In particular, in the case of forming a film on the surface of the substrate particles, the effect of the phase shift on the surface of the substrate particles and all the films is taken into consideration, and a computer simulation is designed so that the combination of the film thicknesses is optimized in advance. Further, a peak shift due to the film layer on the surface of the base particles and a peak shift due to the wavelength dependence of the refractive index are taken into consideration. In actual sample production, refer to the designed spectral curve, and to correct these in the actual film,
Optimum conditions must be found by changing the film thickness such that the reflection peak or absorption bottom becomes the target wavelength with the final target film number by a spectrophotometer or the like. Even in the case of coloring an irregularly shaped powder, interference by the multilayer film occurs, and a basic film design is performed with reference to the conditions of the interference multilayer film of the spherical powder. The peak position of each unit film constituting the above-mentioned multilayer film can be adjusted by the film thickness of each layer, and the film thickness can be adjusted by the solution composition and the reaction time and the number of additions of the raw materials, and the desired color can be obtained. be able to. As described above, a monochromatic powder can be obtained by finding the optimum conditions while changing the film forming conditions such as the film forming solution so that the reflection peak and the absorption bottom have the target wavelength in the final target film number. Further, by controlling the combination of the substances constituting the multilayer film and the thickness of each unit film, it is possible to adjust the color development due to the interference of the multilayer film. Thereby, the powder can be vividly colored to a desired color without using a dye or a pigment. However, if necessary, a coating layer or a colored layer using a coloring material can be provided.

The following are specific examples of the coloring material applied as required, but the present invention is not limited to these specific examples. Specifically, for example, as a blue colorant, (organic dye) phthalocyanine dye, oil dye, lake dye, etc., (cyan pigment) phthalocyanine pigment, lake pigment, etc.
(Inorganic pigment) Metal oxide powders such as titania, alumina, silica, zirconia, ceria, and zinc oxide, and composite oxide pigments such as cobalt aluminate. Examples of the yellow colorants include (organic dyes) monoazo dyes, azomethine dyes, oil dyes, lake dyes, etc., (pigments) benzidine yellow pigments, phorone yellow, acetoacetic anilide, insoluble pigments and the like. Examples of green colorants include (organic dyes) phthalocyanine green dyes, lake dyes such as malachite green, oil dyes, (organic pigments) naphthol green pigments such as pigment green, and green insoluble azo pigments such as green gold. Phthalocyanine green pigments (inorganic pigments) cobalt green (CoO
-Zn-MgO), viridian, emerald green,
Chrome green etc. Examples of red colorants include (organic dyes) lake red dyes, oil red dyes, etc., (organic pigments) naphthol red insoluble azo pigments, red insoluble azo pigments, red naphthol pigments, red lake pigments, and the like. Pigments) lead red, cadmium red, etc. Magenta colorants include (dye) anthraquinone dyes,
Phosphorus-tungsten-molybdate lake pigments of (pigments) xanthene-based magenta dyes, such as thioindigo, oil-based magenta dyes, 2,9-dimethylquinacridone, naphtho-
Coloring materials comprising an insoluble azo pigment, a xanthene dye and an organic carboxylic acid. Examples of cyan colorants include (organic dyes) phthalocyanine dyes, oil dyes, lake dyes, (organic pigments) phthalocyanine pigments, lake pigments, (inorganic pigments) titania, alumina, silica, zirconia, ceria, Examples include metal oxide powders such as zinc oxide, and composite oxide pigments such as cobalt aluminate.

Further, a toning material can be used if necessary. The toning material basically adjusts the color,
It is used to color match a desired color using a plurality of pigments. Specific examples of the toning material to be applied include the following, but the present invention is not limited to these specific examples, and it is also possible to add another pigment or dye as needed and perform toning It is. Specifically, for example, as a blue color toning material, (organic dyes / pigments)
Lake dyes such as alkali blue lake and peacock blue lake; lake pigments; phthalocyanine pigments such as metal-free phthalocyanine and copper phthalocyanine; oxides such as (inorganic pigments) ultramarine; sulfide composite pigments; iron blue; Copper oxide blue-blue pigments, cobalt oxide-based complex oxides such as cobalt blue and cerulean blue, and blue pigments. Examples of yellow color toning materials include (organic dyes) fast dyes such as first yellow, and the like.
(Organic pigment) Hanser Yellow, Naphthol Yellow,
Azo pigments such as CI Pigment Yellow and Permanent Yellow, (inorganic pigments) chromates such as lead, zinc and barium (red-mouthed graphite, chromium vermillion), sulfides such as cadmium sulfide, and composite oxidation such as titanium yellow Pigments. Examples of green color toning materials include (organic dyes) such as lake dyes such as malachite green lake and acid green lake, (organic pigments) nitroso pigments such as pigment green and naphthol green, azo pigments such as green gold, and phthalocyanine green. Phthalocyanine pigments such as polychrome copper phthalocyanine, etc. (inorganic pigments) chrome green, zinc green, chromium oxide,
Chromium-based oxides and hydrated oxides such as hydrated chromium (Viridian); copper-based oxides such as emerald green; and cobalt-based oxides such as cobalt green. Examples of red color toning materials include (organic dyes) lake dyes such as eosin lake and rhodamine lake, quinacridone dyes and pigments such as Cinquasia Red, (organic pigments) azo pigments such as permanent red and para red, and brilliant fast red. And sulfide pigments such as cadmium red and mercury red (inorganic pigments). Examples of orange toning materials include (organic pigments) azo pigments such as permanent orange, benzene orange, Hansa Yellow, etc., (inorganic pigments) oxides (red mouth yellow lead) such as lead chromate, and chromate and lead sulfate. Examples of purple toning materials such as composites (chromium vermillion) include (organic dyes) lake dyes such as methyl violet lake, (organic pigments) azo pigments such as fast violet, (inorganic pigments) cobalt phosphate Pigments such as salts, phosphates such as manganese phosphate, and composite oxides of cobalt arsenic, and the like. Further, as a toning material for increasing the lightness, a white pigment (coloring material), for example, titanium oxide, zinc oxide, tin oxide, silicon oxide, antimony oxide, lead oxide, or a composite oxide thereof, Also, carbonates such as calcium carbonate, magnesium carbonate and barium carbonate, or sulfates such as barium sulfate and calcium sulfate, sulfides such as zinc sulfate and composite oxides obtained by sintering the above oxides, carbonates and sulfates And composite hydrated oxides.

Next, in preparing the fluorescent pigment composition of the present invention thus obtained, (1) a color ink or a paint-like composition (fluid) and (2) a color toner or a color dry ink-like composition (powder) ) Will be described. (1) In the present invention, as a medium (vehicle) of the color ink or the paint-like composition (fluid), a conventionally known varnish used for color printing, color magnetic printing, and color magnetic paint can be used. For example, a liquid polymer, a polymer or a monomer dissolved in an organic solvent, or the like can be appropriately selected and used depending on the type of powder, the application method of the ink, and the application.

Examples of the liquid polymer include dienes such as polypentadiene and polybutadiene, polyethylene glycols, polyamides, polypropylenes, waxes, and knitted copolymers thereof. Polymers soluble in organic solvents include olefin polymers, acrylic resins such as oligoester acrylates, polyesters, polyamides, polyisocyanates, amino resins, xylene resins, ketone resins, diene resins. And rosin-modified phenolic resins, diene rubbers, chloroprene resins, waxes, and modified products and copolymers thereof. Examples of the monomer soluble in the organic solvent include styrene, ethylene, butadiene, propylene and the like. Examples of the organic solvent include alcohols such as ethanol, isopropanol and normal propanol, ketones such as acetone, benzene, toluene, xylene,
Examples thereof include kerosene, benzene hydrocarbons, esters, ethers, and modified products and copolymers thereof.

(2) Color toner, color dry ink,
The color dry paint-like composition (powder) is obtained by directly kneading a resin coated with a fluorescent multi-layer coating and, if necessary, a colorant, and pulverizing the mixture to obtain a powdery fluorescent pigment composition. Can be obtained. Further, the powder coated with the multilayer film can be made into a powdery fluorescent pigment composition by using a polymerization method such as an emulsion polymerization method or a suspension polymerization method. In the case of the powdery fluorescent pigment composition, (a) the resin produced by the above-mentioned pulverization method is not particularly limited, but polyamide, epoxy resin, polyester, melamine resin, polyurethane, vinyl acetate resin , A silicon resin, an acrylate, a methacrylate, a polymer or a copolymer of styrene, ethylene, butadiene, propylene and derivatives thereof. (B) In the case of the polymerization method, polymerization is started from one or a mixture of one or more of ester, urethane, vinyl acetate, organosilicon, acrylic acid, methacrylic acid, styrene, ethylene, butadiene, propylene and the like, and the polymer or These copolymers are formed.

The fluorescent pigment composition of the present invention is, as described above,
It takes the form of (1) a color ink or paint-like composition (fluid) and (2) a color toner or color dry ink-like composition (powder). In the case of a fluid state, it is a color ink, a paint, etc., and the solidifying agent is used for the coloring material, the toning material, and the resin that is slowly dried, a thickening agent for increasing the viscosity, and a fluid for decreasing the viscosity. Components such as a dispersant and the like can be included for dispersing the agent and the particles. On the other hand, in the case of powder, (a) when the powder is produced by a pulverization method, a solidification accelerator is used for the coloring material, the toning material, and the resin that is slowly dried to reduce the viscosity at the time of kneading. Can contain components such as a fluidizing agent, a dispersant for dispersing the particles, a charge controlling agent for fixing to paper or the like, and a wax. (B) When a polymerization method is used, the colorant or toning material, polymerization initiator, polymerization accelerator, thickener for increasing the viscosity, dispersant for dispersing the particles, dispersant, paper, etc. And a component such as a charge control agent and wax for fixing to the toner.
The multilayer coating powder in the fluorescent pigment composition of the present invention can be applied to wet and dry color printing and wet and dry color magnetic printing by using a single powder or a combination of a plurality of powders having different spectral characteristics. Using powder of three primary colors,
It has a function to identify six combinations of visible light, invisible light (ultraviolet and infrared), fluorescent color and magnetism, and electricity (change of electric field), and requires security functions such as color magnetic ink to prevent forgery of printed matter. It can be applied to other uses.

When the fluorescent pigment composition of the present invention is applied as a color ink or a paint composition or a color toner, a color dry ink or a color dry paint composition to a substrate, printed, melt-transferred or applied to an object to be coated, The relationship between the content of the fluorescent multilayer film-coated powder and the resin in the pigment coating composition is 1: 0.5 to 1:15 in volume ratio. If the content of the medium is too small, the applied film does not adhere to the object to be coated.
On the other hand, if the amount is too large, the color of the pigment becomes too light and cannot be said to be a good ink or paint. The relationship between the total amount of the pigment and the resin in the color ink or the coating composition and the amount of the solvent is 1: 0.5 to 1:10 by volume ratio. High viscosity and cannot be applied uniformly. On the other hand, if the amount of the solvent is too large, it takes time to dry the coating film, and the efficiency of the coating operation is extremely reduced.

The color density of a coating film when printing, melt-transferring, or applying a coating material to a substrate is determined by the amount of pigment per unit area of the substrate. After the paint is dried, the amount of the fluorescent multilayer film-coated powder of the present invention on the object to be coated is 5 to 30 per square meter in area density.
0 g, preferably 10 to 150 g, gives a good coating color. If the area density is smaller than the above value, the background color of the object to be coated appears, and if the area density is larger than the above value, the color density of the coating color does not change, which is uneconomical. That is,
Even if the pigment is placed on the object to be coated with a certain thickness or more, the light does not reach the pigment on the lower side of the coating film. It is uneconomical to make the coating film thicker than such a thickness, because the coating thickness exceeds the hiding power of the coating material, so that the coating effect is not obtained. However, in the case of thick coating, the thickness of the coating film is reduced because the thickness of the coating film is reduced in consideration of the abrasion of the coating film.

[0039]

[Example 1]

(When a magnetic material is coated with a multilayer film and a phosphor is coated by mixing and dispersing) (First layer silica coating) Carbonyl iron powder manufactured by BASF (average particle size 1.8 μm, magnetization at 10 kOe is 203 emu)
/ g) 20 g was dispersed in a solution prepared by dissolving 3.5 g of silicon ethoxide in 158.6 g of ethanol, and 8.0 g of ammonia water (29%) prepared in advance and deionized while stirring. A mixed solution of 8.0 g of water was added. After the addition, the reaction was carried out at room temperature for 5 hours. After the reaction, dilute and wash with sufficient ethanol, filter,
It dried at 110 degreeC with a vacuum dryer for 3 hours. After drying, 30 minutes at 800 ° C. in a nitrogen atmosphere using a rotary tube furnace.
Subjected to partial heat treatment, cooling, silica coated iron powder to obtain a A _1.

(Second layer titania coating) In a separable flask, 20 g of the above silica-coated powder A ₁
After dispersing in advance in a liquid obtained by adding 4.6 g of titanium isopropoxide to 198.3 g of ethanol, a solution obtained by mixing 6.0 g of pure water prepared in advance with 47.9 g of ethanol with stirring was added for 1 hour. And dropped. After the addition, the reaction was carried out at room temperature for 4 hours. After the reaction, the resultant was diluted and washed with sufficient ethanol, filtered, and dried in a vacuum drier.
It was dried at 0 ° C. for 3 hours. After drying, the resultant was further subjected to a heat treatment at 650 ° C. for 30 minutes in a nitrogen atmosphere using a rotary tube furnace, and cooled to obtain silica / titania-coated iron powder and A ₂ . The resulting silica / titania-coated iron powder, A ₂ is satisfactory dispersibility and was an independent particle. Silica / titania-coated iron powder, the thickness of the titania film of A ₂ was 55 nm. The peak wavelength of the spectral reflection curve of this powder was 463.
nm, the reflectance at the peak wavelength was 37%, and it was a vivid blue-green color. Further, the magnetization of this powder at 10 kOe was 176 emu / g.

(Third-layer silica coating) 20 g of silica / titania-coated iron powder and A ₂ were dispersed in a solution of 3.5 g of silicon ethoxide in 158.6 g of ethanol in advance, and then prepared with stirring. A mixed solution of 8.0 g of the previously prepared aqueous ammonia (29%) and 8.0 g of deionized water was added. After the addition, the reaction was carried out at room temperature for 5 hours. After the reaction, the reaction mixture was diluted and washed with sufficient ethanol, filtered, and dried in a vacuum dryer at 110 ° C. for 3 hours. After drying, heat treatment was performed at 800 ° C. for 30 minutes in a nitrogen atmosphere using a rotary tube furnace, and the mixture was cooled.
Titania / silica-coated iron powder to obtain A _3.

[0042] In (4-layer Titania Coating) In a separable flask, the silica / titania / silica-coated iron powder, and A _3, dispersed in a liquid by adding titanium isopropoxide 4.6g beforehand ethanol 198.3g After that, while stirring, pure water prepared in advance 6.
A solution obtained by mixing 0 g with 47.9 g of ethanol was added dropwise over 1 hour. After the addition, the reaction was carried out at room temperature for 4 hours.
After the reaction, the reaction mixture was diluted and washed with sufficient ethanol, filtered, and dried in a vacuum dryer at 110 ° C. for 3 hours. After drying, the mixture was further dried at 650 ° C. in a nitrogen atmosphere using a rotary tube furnace.
Subjected to 0 minutes heat treatment, cooling, silica / titania / silica / titania-coated iron powder to obtain a A _4. The resulting silica / titania / silica / titania-coated iron powder, A ₄ is satisfactory dispersibility and was an independent particle. Silica / titania / silica / titania-coated iron powder, the thickness of the titania film of A ₄ was 56 nm. The peak wavelength of the spectral reflection curve of this powder is 435 nm, and the reflectance at the peak wavelength is 4 nm.
At 6%, it was a bright cyan color. Further, the magnetization of this powder at 10 kOe was 132 emu / g.

(Powder hydrophobizing treatment) Silica / titania / silica / titania-coated iron powder, 20 g of A ₄ , 0.5 g of silicon ethoxide in 158.6 g of ethanol in advance
After dispersing in a solution in which was dissolved, a mixed solution of 3.0 g of ammonia water (29%) and 3.0 g of deionized water prepared in advance was added with stirring. After the addition, the reaction was carried out at room temperature for 1 hour. After the reaction, the mixture is diluted and washed with sufficient ethanol, filtered, and dried at 110 ° C.
Dried for hours. After drying, cooling and hydrophobic treatment of silica /
Titania / silica / titania-coated iron powder to obtain a A _5.

(Preparation of Fluorescent Pigment Composition, Mixing and Dispersion of Phosphor) The thus obtained multilayer film-coated powder, A ₅ , 3
0 g, 2.5 g of acrylic polymer (trade name: Technobit, manufactured by Kulzer) in 80 g of ethanol in advance
Is dispersed in a solution in which is dissolved, and a mixed solution obtained by adding 18 g of copper-containing zinc cadmium sulfide fine particles (fluorescent substance), 20 g of titanium oxide (hydrophobic silicone treated product: coloring material) and 3.2 g of hydroxypropylcellulose is added to zirconia. The dispersion treatment was performed for 8 hours by a ball mill to obtain a paint dispersion AL of the fluorescent pigment composition.

(Coating and Spectral Characteristics) The dispersion AL of the above fluorescent pigment composition was applied to art paper using a blade coater. The coating amount (after drying) of the fluorescent pigment composition is 59 g / m
^{And 2} . After drying, the spectral reflectance curve of the obtained coated paper 1 was as shown in FIG. The color of the coated paper 1 was a bright cyan color with a peak wavelength of 433 nm and a reflectance of 65%.
Furthermore, in the ultraviolet region, light near 365 nm is reflected by about 67%, and in the infrared region, light near 870 nm is reflected by about 56%. It is possible to make a true / false judgment with four types of infrared rays. When the coated paper 1 was irradiated with an ultraviolet lamp in a dark place, the color of the paper 1 emitted a pale blue fluorescent light (FIG. 2). The 10kOe per 1 m ² of the coating Gion 1
Was 3175 emu / m ² .

[Comparative Example 1] (When a magnetic material is coated with a multilayer film and a fluorescent material is not mixed) The same operation as in Example 1 was performed. However, copper-containing zinc cadmium sulfide fine particles as a fluorescent substance were not mixed in the dispersion in the preparation of the fluorescent pigment composition. The reflection peak of the coated paper was 433 nm in the visible light region, and the reflectance was 65%. However, even when the coated paper was irradiated with an ultraviolet lamp in a dark place, no fluorescent color was observed.

Example 2 (When a magnetic substance is coated with a multilayer film, and a phosphor is mixed and dispersed and powdered by spray drying) (First layer silica coating) Carbonyl iron powder manufactured by BASF (average particle size 1.8 μm) The magnetization at 10 kOe is 203 emu
/ g) 20 g was dispersed in a solution prepared by dissolving 4.4 g of silicon ethoxide in 158.6 g of ethanol, and 8.0 g of ammonia water (29%) previously prepared and deionized while stirring. A mixed solution of 8.0 g of water was added. After the addition, the reaction was carried out at room temperature for 5 hours. After the reaction, dilute and wash with sufficient ethanol, filter,
It dried at 110 degreeC with a vacuum dryer for 3 hours. After drying, 30 minutes at 800 ° C. in a nitrogen atmosphere using a rotary tube furnace.
Subjected to partial heat treatment, and cooled to obtain silica-coated iron powder, and B _1.

(Second layer titania coating) In a separable flask, 20 g of the above silica-coated powder B ₁ was
After dispersing in a liquid obtained by adding 4.6 g of titanium isopropoxide to 198.3 g of ethanol in advance, a solution obtained by mixing 6.3 g of pure water prepared in advance with 47.9 g of ethanol with stirring was added for 1 hour. And dropped. After the addition, the reaction was carried out at room temperature for 4 hours. After the reaction, the resultant was diluted and washed with sufficient ethanol, filtered, and dried in a vacuum drier.
It was dried at 0 ° C. for 3 hours. After drying, the mixture was further subjected to a heat treatment at 650 ° C. for 30 minutes in a nitrogen atmosphere using a rotary tube furnace, and cooled to obtain silica / titania-coated iron powder and B ₂ . The resulting silica / titania-coated iron powder, B ₂ has good dispersibility and was an independent particle. Silica / titania-coated iron powder, the thickness of the titania film of B ₂ was 65 nm. The peak wavelength of the spectral reflection curve of this powder was 573.
nm, the reflectance at the peak wavelength was 35%, and the color was bright green. Further, the magnetization of this powder at 10 kOe is 1
It was 68 emu / g.

(Third-layer silica coating) 20 g of silica / titania-coated iron powder and B ₂ were dispersed in a solution in which 3.9 g of silicon ethoxide was previously dissolved in 158.6 g of ethanol, and then prepared with stirring. A mixed solution of 8.0 g of the previously prepared aqueous ammonia (29%) and 8.0 g of deionized water was added. After the addition, the reaction was carried out at room temperature for 5 hours. After the reaction, the reaction mixture was diluted and washed with sufficient ethanol, filtered, and dried in a vacuum dryer at 110 ° C. for 3 hours. After drying, heat treatment was performed at 800 ° C. for 30 minutes in a nitrogen atmosphere using a rotary tube furnace, and the mixture was cooled.
Titania / silica-coated iron powder to obtain a B _3.

(Fourth Layer Titania Coating) In a separable flask, 20 g of the above silica / titania / silica-coated iron powder, B ₃ , was previously dissolved in 198.
After dispersing in a solution prepared by adding 4.6 g of titanium isopropoxide to 3 g, a solution prepared by mixing 6.0 g of pure water prepared in advance with 47.9 g of ethanol was added dropwise with stirring over 1 hour. did. After the addition, the reaction was carried out at room temperature for 4 hours. After the reaction, the reaction mixture was diluted and washed with sufficient ethanol, filtered, and dried in a vacuum dryer at 110 ° C. for 3 hours. After drying,
Further, using a rotary tube furnace, in a nitrogen atmosphere, 65
0 ℃ subjected to 30 minutes heat treatment at, cooled, silica / titania / silica / titania-coated iron powder to obtain a B _4. Obtained silica / titania / silica / titania-coated iron powder, B
₄ had good dispersibility, and each was a single particle. silica/
Titania / silica / titania-coated iron powder, the thickness of the titania film of B ₄ was 69 nm. The peak wavelength of the spectral reflection curve of this powder was 567 nm, the reflectance at the peak wavelength was 46%, and the powder was bright yellow-green. Further, the magnetization of this powder at 10 kOe was 126 emu / g.

(Powder Hydrophobizing Treatment) Silica / titania / silica / titania-coated iron powder, 20 g of B ₄ , 0.5 g of silicon ethoxide in 158.6 g of ethanol in advance
After dispersing in a solution in which was dissolved, a mixed solution of 3.0 g of ammonia water (29%) and 3.0 g of deionized water prepared in advance was added with stirring. After the addition, the reaction was carried out at room temperature for 1 hour. After the reaction, the mixture is diluted and washed with sufficient ethanol, filtered, and dried at 110 ° C.
Dried for hours. After drying, cooling and hydrophobic treatment of silica /
Titania / silica / titania-coated iron powder to obtain a B _5.

(Preparation of Fluorescent Pigment Composition, Mixing and Dispersion of Phosphor) The thus obtained multilayer-coated powder, B ₅ , 3
0 g was previously dispersed in a solution prepared by dissolving 30 g of a styrene polymer and 5 g of an acrylic polymer (trade name: Technobit, manufactured by Kulzer) in 80 g of cyclohexane, and then 10 g of rhodamine B particles (fluorescent substance) and titanium oxide (hydrophobic treated product: A mixed solution to which 20 g of a coloring material) and 3.2 g of hydroxypropylcellulose were added was subjected to a dispersion treatment for 8 hours by a zirconia ball mill to obtain a paint dispersion BL of a fluorescent pigment composition.

(Powdering and Spectral Characteristics) The paint dispersion BL of the fluorescent pigment composition was spray-dried at 90 ° C. in a nitrogen gas atmosphere using a spray dryer to obtain a spherical powder, a fluorescent pigment composition BP. I got The reflection peak of this spherical powder and the fluorescent pigment composition BP is 586 nm in the visible light region,
The reflectance was 63%, and it was bright yellow. The spherical powder fluorescent pigment composition BP was packed in a quartz glass holder and emitted a pale orange fluorescent light when irradiated with an ultraviolet lamp in a dark place. Further, the magnetization of this spherical powder fluorescent pigment composition BP at 10 kOe was 63 emu / g.

[0054]

As described above, the fluorescent pigment composition of the present invention has both color and fluorescent properties, and can be used for color printing and coating of beautiful and stable monochromatic colors such as blue, green and yellow. It becomes ink, filler and paint for construction. In addition, since it has an interference reflection peak in addition to visible light, detection of reflected light by ultraviolet rays and infrared rays, and identification of printed matter based on the presence or absence of fluorescence, which can determine authenticity without using a special reading device, forgery with high accuracy Prevention becomes possible. Having these excellent functions and utilizing a magnetic material as the base,
Applicable as a coloring material for high-performance color magnetic printing inks, and identifies six combinations of visible light, invisible light (ultraviolet and infrared), fluorescence and magnetism, and electricity (electric field change). It has a function, can enhance the effect of preventing forgery of printed matter, and has extremely high practicality.

[Brief description of the drawings]

FIG. 1 is a graph showing a spectral reflectance curve of the fluorescent pigment composition obtained in Example 1.

FIG. 2 is a graph showing a fluorescence spectral reflectance curve of the fluorescent pigment composition obtained in Example 1.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kiyoshi Hoshino 8-1, Hirai-machi, Hinode-cho, Nishitama-gun, Tokyo Nippon Steel Mining Co., Ltd. 5 1403 F term (reference) 4H001 XA08 XA09 XA12 XA14 XA15 XA16 XA20 XA30 XA31 XA38 XA39 XA48 XA56 XA74 XA82 YA13 YA25 YA29 YA33 AYA AA AA AA AA AA AA AA AA AA AA AA27 AA30 CA03 CA05 CA09 CA18 CB28 CC02 CC12 CC13 CC14 CC16 CC22 CC23 CC24 CC26 CC27 CC28 DD05 DD12 EE04 FF02 FF11 4J038 EA011 KA08 KA15 KA20 NA22

Claims (5)

[Claims] 1. A fluorescent pigment composition comprising a multi-layer coating powder having a plurality of coating films on substrate particles and a fluorescent substance. 2. The fluorescent pigment composition according to claim 1, wherein the multilayer film exhibits an optical interference effect. 3. The forgery-preventing fluorescent pigment composition according to claim 1, wherein the multilayer film exhibits a specific interference reflection peak in a region other than the visible light region. 4. The fluorescent pigment composition according to claim 1, wherein said base particles are magnetic particles. 5. The fluorescent pigment composition according to claim 1, further comprising a coloring material.