JPH1124319A - Red toner and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a color toner showing sharp red tone which can give excellent integrated functions even when the toner is used for a one-component developing method, and to provide an efficient and high-accuracy producing method of the toner. SOLUTION: The particle of this toner consists of the base particle 1, plural film layers produced by alternately depositing films 3 having a large refractive index and films 2 having a small refractive index on the surface of the base particle 1, and an adhesive resin layer 4 having dispersion of a pigment and a dye around the film layers. The toner is produced to have the reflection spectrum with a peak in 600 to 800 nm range. In the forming process of the multilayered film of this method, the refractive index and reflection spectrum of the base particle 1 and the film layers are controlled to satisfy the conditions above described.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a red toner and a method for producing the same, and more particularly to a red toner for a copying machine.
The present invention relates to a red toner used for various purposes such as a color magnetic toner for a printer and a color toner for printing, and a method for producing the same.

[0002]

2. Description of the Related Art At present, image forming methods in electrophotographic copying, printing, and the like include a two-component developing method using a carrier having magnetic or dielectric properties and a toner as a coloring material in combination with a toner itself. There is a one-component developing method having magnetic or dielectric properties. In the one-component developing method, a carrier is not used, so that the developing device is simplified (the size of the developing device is approximately one-third to two-thirds of the two-component developing method), and the developer is controlled. There are many advantages such as ease of operation.
However, when attempting to form a color image, the toner became dark and did not become a vivid color. This is 1
To obtain a clear color image by the component-based development method, it is necessary to color the toner itself in a vivid color.However, since the base particles serving as the base are generally black, a colored film is directly provided on the surface thereof. Is also darkened as a whole.

For this reason, at present, two-color image formation is required.
Although a component-based developing method is employed, since four colors of three primary colors and black are required for color copying, the developing device naturally becomes large. In addition, there are also problems such as management of the developer and treatment of carriers generated after image formation. Therefore, if vivid colors can be obtained by the one-component developing method, the copier becomes simpler and more compact, and the management of the developer and the processing of the carrier are also eliminated. There is a strong need for a technique for producing a toner for a method.

[0004] On the other hand, the present inventors previously have another property in addition to the property provided only by certain powder particles,
In order to provide a powder having a composite function, by using the powder particles as a substrate, dispersing the substrate particles in a metal alkoxide solution, and hydrolyzing the metal alkoxide,
A method for forming a uniform metal oxide film having a thickness of 0.01 to 20 μm on the surface of base particles (Japanese Patent Laid-Open No. 6-228604)
Japanese Patent Application Laid-Open No. 7-90310), a functional powder in which a plurality of thin films made of metal oxide and thin films made of metal are alternately provided on the surface (Japanese Patent Application Laid-Open No. 7-90310), The resulting powder is heat-treated to propose and manufacture a powder having a denser and more stable metal oxide multilayer film (Japanese Patent Application No. 7-80832).

[0005] The powders provided with a plurality of metal oxide films, metal films and the like as described above can be provided with a special function by adjusting the thickness of each layer. Coating films with different refractive indices on the surface of
Providing a thickness corresponding to one-half wavelength provides a powder that reflects all incident light. When this is applied to a magnetic powder having magnetic particles as base particles, it is possible to produce a toner powder that reflects all light and shines white, and further constitutes the light interference multilayer film on the surface of the powder. By setting the film thickness so that each unit coating layer has a specific interference reflection peak of the same wavelength, a single-colored powder can be obtained without using a dye or a pigment, and a resin layer is provided thereon. For example, it suggests that a vivid color toner can be manufactured (WO96 / 28269).

The present inventors have made it possible to obtain a colored composite raw material powder such as white from the light interference multilayer film on the base particles by the above method. By providing an organic polymer film for a binder thereon, and by adding a colorant to the organic polymer film, a color toner capable of forming a vivid color image even with a one-component system is provided. (Japanese Patent Application No. 8-147420).

[0007]

However, there is no clear disclosure of a technique for obtaining a colored powder having a desired specific color tone, and in the conventional method, a multilayer film exhibiting a bright red color is used. The condition range for developing the color of the film-coated powder was not clear. For example, the red color is
It is one of the three primary colors of light and is an important pigment that gives psychological warmth, vitality, passion and attention to humans. Obtaining a red toner having such a red color tone and a specific function is of great industrial significance. Furthermore, when the colored multilayer film-coated powder is combined with a resin to form a color toner, particularly when the base is dark, when the transparent resin layer is colored with a dye having high transparency, the coloring power of the dye is weak. Since the color of the resin layer does not match the color of the colored multilayer film-coated powder, desired toning may not be achieved.

Accordingly, an object of the present invention, as described above,
By using powder particles as a substrate, a technology for forming a multilayer film coating such as a metal oxide film on the surface thereof is further developed to have a vivid reddish color tone that is industrially useful, and one-component development. It is an object of the present invention to provide a color toner capable of performing an excellent combined function even in a method, and an efficient and highly accurate manufacturing method of the toner.

[0009]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to achieve the above-mentioned object, and as a result, when forming a multilayer-coated powder, the combination of films and the thickness of each film have been considered. ,
By further improving the method of controlling them, it is possible to obtain a powder having a higher maximum reflectance and a larger amplitude of the spectral reflection waveform, and to improve the color of the powder itself. When the range of the wavelength of the maximum value observed when forming each layer of the alternating film of silica and silica is limited to a specific range, it has been found that a bright red powder can be obtained, and the present invention has been reached. .

That is, the present invention is as follows. (1) having a plurality of coating layers in which a coating having a large refractive index and a coating having a small refractive index are stacked adjacent to each other on the surface of the base particles, and an adhesive resin layer in which a pigment and a dye are dispersed outside the coating layer;
A red toner having a reflection spectrum having a peak between 600 and 800 nm. (2) when the refractive index of the base particles is larger than the refractive index of the first layer coating which is in contact with the surface of the base, the coating has an even number of layers;
The red toner according to the above (1), wherein when the refractive index of the base particles is smaller than the refractive index of the first layer coating, the coating has an odd number of layers. (3) The red toner according to (1) above, wherein the base particles are a magnetic substance, a dielectric substance, or a conductor. (4) The red toner according to (1), wherein the pigment is dispersed in the adhesive resin layer at 5 to 60 vol%. (5) The red toner according to (4), wherein the adhesive resin layer has a two-layer structure of an inner layer of 5 to 60 vol% of pigment and an outer layer of 0 to 15 vol% of pigment.

(6) A method for producing a red toner comprising a plurality of coating layers having different refractive indices on the surface of base particles and an adhesive resin layer in which pigments and dyes are dispersed outside the coating layers. Forming a plurality of layers in which a film having a large refractive index and a film having a small refractive index are stacked side by side on the surface of the particles;
A method for producing a red toner, wherein the conditions of the base particles and the coating layer are set so as to exhibit a reflection spectrum having a peak between 800 nm and 800 nm. (7) When the refractive index of the base particles is larger than the refractive index of the first layer coating in contact with the surface of the base, an even layer coating is formed, and the refractive index of the base particles is higher than the refractive index of the first layer coating. (6) The method for producing a red toner according to (6) above, wherein an odd-numbered layer is formed when the particle size is too small. (8) The method for producing a red toner according to (6), wherein the base particles are a magnetic substance, a dielectric substance, or a conductor. (9) The method for producing a red toner according to (6), wherein the pigment is dispersed and contained in the adhesive resin layer in a range of 5 to 60 vol%. (10) The method for producing a red toner according to (9), wherein the adhesive resin layer has a two-layer structure of an inner layer of 5 to 60 vol% of pigment and an outer layer of 0 to 15 vol% of pigment.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the case where a plurality of layers of a metal oxide, a metal film and the like are formed on the surface of the base particles, the coating film (a layer of a film which covers the base particles and participates in light interference) A special function can be given by adjusting the thickness of each layer. For example, an alternating coating film having a different refractive index is formed on the surface of the base particles so that the refractive index n of the material forming the coating film and the wavelength of visible light are between 600 and 800 nm so as to satisfy the following expression (1). When an appropriate thickness and number of the alternating films having a thickness d corresponding to an integer m times 1/4 of
Light having a wavelength λ between 800 nm and 800 nm (using the interference reflection of Fresnel) is reflected or absorbed. nd = mλ / 4 (1)

Utilizing this effect, a film having a film thickness and a refractive index that satisfies the formula (1) is formed on the surface of the substrate particles at a target wavelength between 600 and 800 nm, Further, by alternately repeating coating of a film having a different refractive index once or more thereon, a film having a reflection peak between 600 and 800 nm is formed. At this time, the order of the materials to be formed is determined as follows. First, it is preferable that the first layer be a film having a low refractive index when the refractive index of the base serving as a nucleus is high, and that the first layer be a film having a high refractive index in the opposite relationship. The film thickness is measured and controlled as a reflection waveform with a spectrophotometer or the like, and the change in the optical thickness, which is the product of the film refractive index and the film thickness, is controlled. Design thickness. For example, as shown in FIG.
When it is precisely adjusted to the range of 00 to 800 nm, a red-colored monochromatic colored powder can be obtained without using a dye or a pigment.

However, in the case of an actual substrate, the particle size of the substrate,
It is necessary to design in consideration of the shape, the phase shift at the mutual interface between the film material and the base particle material, the peak shift due to the wavelength dependence of the refractive index, and the like. For example, when the shape of the base particle is a parallel plate, the Fresnel interference by the parallel film formed on the particle plane is designed under the condition that n in the above formula (1) is replaced by N in the following formula (2). I do. In particular, in the case where a metal film is included even when the shape of the base is a parallel plate, the attenuation coefficient κ is included in the refractive index N of the metal of the formula (2). In the case of a transparent oxide (dielectric), κ is very small and can be ignored. N = n + iκ (i represents a complex number) (2) If this attenuation coefficient κ is large, the phase shift at the mutual interface between the film material and the base material becomes large, and furthermore, interference due to the phase shift occurs in all the layers of the multilayer film. Affects 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 pale especially when coloring in a red color system. 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 are phase shifts due to the oxide layer on the surface of the substrate and peak shifts due to the wavelength dependence of the refractive index. To correct these, use a spectrophotometer, etc.
The reflection peak is a target wavelength of 600 to 8 which is the final target film number.
It is necessary to find the optimal conditions to be in the range of 00 nm.

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 also be designed to be reddish as shown in FIG. 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 increases, the interference inside the multilayer film becomes more complicated. Even in the case of a multilayer film, based on Fresnel interference,
The reflection spectral curve can be designed in advance by computer simulation so that the combination of film thicknesses 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 to optimize the combination of film thickness in advance. Further, the peak shift due to the oxide layer on the surface of the base particles and the peak shift due to the wavelength dependence of the refractive index are taken into consideration. In the actual sample production, in order to correct these in the actual film by referring to the designed spectral curves, the film thickness is adjusted by a spectrophotometer or the like so that the reflection peak becomes the target wavelength in the range of 600 to 800 nm in the final target film number. It is necessary to find the optimal conditions while changing the conditions.

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 is determined by the coating conditions for forming a solid phase component such as a metal oxide on the surface of the base particles. By controlling the composition, the solid phase deposition rate, the amount of the substrate, and the like, the film thickness can be accurately controlled, a film having a uniform thickness can be formed, and a desired red color can be obtained. As described above, the reflection peak is 600 to 800 n in the final target film number.
By finding the optimum conditions while changing the film forming conditions such as a film forming solution so as to obtain a target wavelength in the range of m, a red powder can be obtained. 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 red color system without using a dye or a pigment.

An adhesive resin layer containing a pigment and a dye is formed outside (surface) of the plurality of coating layers (layers of the film covering the base particles). This adhesive resin layer not only has a function as a binder for fixing the toner, but also causes a color missing portion due to a gap between the toner particles when the toner adheres to the paper surface. It is preferable to add a colorant to color the periphery of the toner-adhered portion by the spread of the organic polymer film due to the adhesion. By including scattering particles (colorant), it is possible to adjust to a more vivid desired red color system. Color can be facilitated.
In order to suppress the visible light transmission of the adhesive resin layer, the scattering particles are mixed with the scattering particles so that the volume of the scattering particles is 5 to 60 vol% (5 to 50 wt% in weight%) with respect to the volume of the adhesive resin layer. Preferably, more preferably 5
It is preferable that the content be adjusted to a range of 45 vol% (5 to 35 wt%). If it is less than 5 vol%, there is no toning effect by the scattering particles, and if it is more than 60 vol%, the binding power of the resin is lost, making it impossible to form a film, and both are unsuitable.

According to the above structure, a multi-layered light interference coating film comprising a metal compound film and / or a metal film is provided on the base particles, and a powder exhibiting a red color system is formed by the film structure. By forming an adhesive resin layer containing scattering particles thereon, it is possible to obtain a red toner capable of forming a bright color image even with a one-component system.

Hereinafter, the red toner of the present invention and a method for producing the same will be described in detail. In the red toner and the method for producing the same according to the present invention, the base particles on which the metal oxide film or the like is formed are not particularly limited, and may be an inorganic substance containing a metal, an organic substance, a magnetic substance, a dielectric substance and a conductive substance. It may be a body or the like. When the substrate is a metal, any metal such as iron, nickel, chromium, titanium, and aluminum may be used.
Those having magnetism such as cobalt and nickel are preferable. These metals may be alloys, and when having the above-mentioned magnetism, it is preferable to use ferromagnetic alloys.
When the base of the powder is a metal compound, typical examples thereof include oxides of the above-mentioned metals. Examples of the metal oxide include iron, nickel, chromium, titanium, aluminum, silicon, and the like. , Magnesium, barium and the like, or composite oxides thereof. Furthermore, examples of the metal compound other than the metal oxide include a metal nitride and a metal carbide.

However, since the magnetic particles tend to be used in the form of finer particles for improving the resolution, it is preferable to use a magnetic material having a large magnetization. Preferably, it is a magnetic substance having a magnetization of 90 emu / g or more, preferably 150 emu / g or more when a magnetic field of 10 kOe is applied in a powdery state. Such a magnetic material having a high magnetization has a high magnetization of 10 to 90 emu / g (application of a 10 kOe magnetic field) as a whole even when an adhesive resin, a charge control agent, a coloring agent, or the like is added as a color magnetic toner. The raw material powder of a color magnetic toner having

Further, as the base particles other than metal,
It is a semi-metallic or non-metallic compound, especially an oxide, carbide or nitride, and silica, glass beads or the like can be used. Other inorganic substances include inorganic hollow particles such as shirasu balloons (hollow silicate particles), fine carbon hollow spheres (Clekasphere), fused alumina bubbles, aerosil, white carbon, silica fine hollow spheres, calcium carbonate fine hollow spheres, Calcium carbonate, perlite, talc, bentonite, kaolin and the like can be used.

As the organic substance, resin particles are preferable. Specific examples of the resin particles include cellulose powder, cellulose acetate powder, polyamide, epoxy resin, polyester, melamine resin, polyurethane, vinyl acetate resin, silicon resin, acrylate, methacrylate, styrene, ethylene, propylene and these. Spherical or crushed particles obtained by polymerization or copolymerization of a derivative of the above. Particularly preferred resin particles are spherical acrylic resin particles obtained by polymerization of acrylic acid or methacrylic acid ester.

Examples of the shape of the substrate include polyhedrons such as spheres, subspheres, isotropic bodies such as regular polyhedrons, 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,
Those having a range of 0.01 μm to several mm are preferred. Also,
The specific gravity of the base particles is in the range of 0.1 to 10.5.
5.5 is preferred, more preferably 0.1 to 2.8, and still more preferably 0.5 to 1.8. If the specific gravity of the substrate is less than 0.1, the buoyancy in the liquid is too large, and the film needs to be multilayered or very thick, which is uneconomical. On the other hand, when it exceeds 10.5, the film for floating becomes thick, which is also uneconomical.

In the red toner of the present invention, a plurality of coating layers formed on the surface of the base particles having a specific gravity of 0.1 to 10.5 (layers of films which cover the base particles and participate in light interference)
Need to have different refractive indices from each other, and it is desirable that the material forming the coating layer is arbitrarily selected from inorganic metal compounds, metals or alloys, and organic substances.

Typical examples of the inorganic metal compound constituting the coating layer include metal oxides. Specific examples thereof include iron, nickel, chromium, titanium, aluminum, silicon, calcium, magnesium, barium, and zinc. And composite oxides thereof. Further, as metal compounds other than metal oxides, metal sulfides, metal selenides, metal tellurides,
Metal fluorides can be mentioned. More specifically,
Zinc oxide, aluminum oxide, cadmium oxide, titanium oxide, zirconium oxide, tantalum oxide, silicon oxide, antimony oxide, neodymium oxide, lanthanum oxide, bismuth oxide, cerium oxide, tin oxide, magnesium oxide, lithium oxide, lead oxide, cadmium sulfide , Zinc sulfide, antimony sulfide, cadmium selenide, cadmium telluride, calcium fluoride, sodium fluoride, trisodium aluminum fluoride, lithium fluoride, magnesium fluoride and the like can be suitably used.

Examples of simple metals constituting the coating layer include metallic silver, metallic cobalt, metallic nickel, metallic iron, and the like, and metallic alloys include iron / nickel alloys, iron / cobalt alloys, iron / nickel alloy nitrides, and iron / nickel alloys. A nickel / cobalt alloy nitride;

The organic substance constituting the coating layer may be the same or different from the above-mentioned organic substance constituting the core, and is not particularly limited, but is preferably a resin. Specific examples of the resin, cellulose, cellulose acetate, polyamide, epoxy resin, polyester, melamine resin,
Examples include polyurethane, vinyl acetate resin, silicon resin, acrylic acid ester, methacrylic acid ester, styrene, ethylene, propylene and a polymer or copolymer of these derivatives.

As described above, various materials can be used as the material constituting the coating layer, and the combination of these materials is determined in consideration of the refractive index of each coating layer, It is necessary to select appropriately according to the object to be coated and the like.

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 base particles by dispersing and emulsion-polymerizing the base particles can be used. b. Film forming method in gas phase (CVD) (PVD)

(2) When an inorganic metal compound film is formed 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 metal film or 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.

Next, as an example, a specific method of forming an alternating multilayer film of a substance having a high refractive index and a substance having a low refractive index in the present invention will be described below. In order to form a film having a high refractive index, for example, 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 By hydrolyzing the alkoxide, a titanium oxide film, a zirconium oxide film, or the like is formed as a high refractive index film on the substrate surface. Thereafter, the powder is subjected to solid-liquid separation, vacuum-dried, and then heat-treated. 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. A coating composition that does not oxidize during heat treatment is in air, and a coating composition that easily oxidizes is in an inert atmosphere at 150 to 1100 ° C (when the substrate is an inorganic powder) or 150 to 500 ° C (when the substrate is not an inorganic powder). ) For 1 minute to 3 hours.

Subsequently, the powder having the high refractive index film is dispersed in an alcohol solution in which a metal alkoxide such as silicon alkoxide or aluminum alkoxide, which has a low refractive index when converted to an oxide, is dispersed. A mixed solution of water, an alcohol and a catalyst is added dropwise while the mixture is dropped, and the alkoxide is hydrolyzed to form a low refractive index film such as silicon oxide or aluminum oxide on the surface of the powder. Then, after the powder is solid-liquid separated and dried in vacuum,
Heat treatment is performed in the same manner as described above. By this operation, a powder having two layers of a high refractive index coating and a low refractive index coating on the surface of the base particles is obtained. Further, by repeating the operation of forming this coating, a powder having a multilayer coating on its surface is obtained. At this time, as described above, a powder having a high reflectivity can be obtained by using a powder in which a high-refractive-index coating and a low-refractive-index coating are alternately provided.

In the present invention, after a film of a metal oxide or the like is coated on the substrate particles, the formed metal oxide film is heat-treated to increase the density of the metal oxide constituting the film. In addition, the refractive index of the film is increased, the difference between the metal oxide film having a high refractive index and the metal oxide film having a low refractive index is increased, and the particle diameter is further reduced. In addition, the heat treatment
It may be performed every time the metal oxide film is coated, or after the metal oxide film is coated and the metal oxide film is sequentially coated thereon. Further, after the hydrolysis, the next coating treatment may be performed without drying, or after drying, the next coating treatment may be performed. However, in order to meet the demand for high resolution at present, finer toner and finer base particles have been developed, and it is necessary to form a uniform film on the surfaces of the base particles.

Next, in the red toner of the present invention and the method for producing the same, an adhesive resin layer containing a pigment and a dye is provided outside (surface) of the plurality of coating layers (layers of the film covering the base particles). It is formed. As a method for forming the adhesive resin layer, a method in which an organic polymer film is directly coated on the surface of a multilayer-coated powder by a PVD method, a CVD method, a spray drying method, or the like is also possible. In order to enhance the adhesion, it is preferable to form a film by a polymerization method. As the polymerization method, a preferable polymerization method can be appropriately selected depending on the type of the organic polymer. Specifically, emulsion polymerization, suspension polymerization, seed polymerization, ins
An itu polymerization method or the like can be employed depending on the type of the organic polymer. Further, depending on the type of the organic polymer, a phase separation method may be employed.

The usable adhesive resin is not particularly limited as long as it can form a film by the above-mentioned polymerization method among the resins used as binder resins for toner. For example, the following polymers can be exemplified. That is, polystyrene, styrene and α-methylstyrene copolymer, aromatic hydrocarbon oligomers and polymers such as styrene and vinyl toluene copolymer,
Olefin oligomers and polymers such as polypropylene, polyethylene and polybutene, ethyl acrylate,
Vinyl oligomers and polymers consisting of copolymers of monomers such as methyl methacrylate, ethyl methacrylate, acrylonitrile, polyacrylic acid, polymethacrylic acid, and vinyl acetate; or diene compounds such as polybutadiene, polypentadiene, and polychloroprene Oligomers, oligomers alone such as ester oligomers such as polyesters or copolymers of these oligomers, hydrocarbon monomers and oligomers, olefin oligomers, vinyl monomers and oligomers, polychloroprene monomers and oligomers, ester monomers and oligomers Copolymers formed from a plurality of monomers and oligomers, such as natural waxes, waxes such as polyethylene wax, and alkyd resins such as rosin-modified alkyd resins It is.

The amount of the adhesive resin layer to be coated is such that the red toner of the present invention spreads to the extent that it does not drop or peel when it adheres to the paper surface. ), The amount is preferably about four times the area occupied by the multilayer-coated powder when adhered to the paper.

In the red toner and the method for producing the same according to the present invention, examples of the coloring agent for coloring the adhesive resin layer include a red coloring agent. Can be. Inorganic pigment: lead red, cadmium red; organic pigment: naphthol red insoluble azo pigment, red insoluble azo pigment, red naphthol pigment, red lake pigment; organic dye: lake dye, oil dye. The content of these colorants in the adhesive resin layer is such that when the red toner adheres to the paper surface, the colorant is uniformly colored over an area of about 2 to about 10 times the projected area occupied by the multilayer-coated powder. Preferably, the amount is as large as possible.

The red toner of the present invention comprises the above-mentioned substrate, light coherent multilayer coating film and adhesive resin layer as essential components, but also includes a charge control agent, a fluidizing agent and a release agent. May be contained in the adhesive resin layer. The charge control agent is an additive added for adjusting the chargeability of the toner, and includes an organic acid, a surfactant, and other dielectric substances. As a material used for a positively charged toner, a metal complex of an alkyl salicylic acid, a metal complex of a dicarboxylic acid, a metal salt of a polycyclic salicylic acid, a metal salt of a fatty acid, or the like can be used. As the material used for the negatively charged toner, a quaternary ammonium salt, a benzothiazole derivative, a guanamine derivative, dibutyltin oxide, a nitrogen-containing compound, a chlorinated paraffin, a chlorinated polyester, or the like can be used. The fluidizing agent is an additive added to improve the fluidity of the toner and prevent unnecessary residual on the paper surface, for example, colloidal silica, Aerosil,
Titanium oxide powder, alumina powder, zinc oxide powder, fatty acid metal salt powder and the like can be used. The release agent is an additive added to prevent the toner from adhering to the fixing roll of the developing machine, and for example, low molecular polyethylene, low molecular polypropylene or the like can be used. It is preferable that the total content of these additives in the adhesive resin layer has an upper limit of about 60% by weight. When the content is larger than the above content, practical magnetic properties cannot be obtained in the case of a magnetic toner.

By combining the above elements, a vivid red-based color magnetic toner can be obtained. FIG. 2 is a schematic cross-sectional view showing one embodiment of the red toner according to the present invention described above. As shown in FIG. 2, a metal compound film 2 and another metal are formed on a base particle 1. An optical interference multilayer film is formed by laminating the compound film 3 and the outermost surface is further covered with an adhesive resin layer 4 containing scattering particles. Note that one of the metal compound film 2 and the other metal compound film 3 may be a metal film.

[0042]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, which, of course, are not intended to limit the scope of the present invention.

Example 1 (Production of powder coated with a multilayer film) First layer: silica coating Carbonyl iron powder manufactured by BASF (average particle size: 1.8 μm) 10
g was dispersed in 100 ml of ethanol, and the temperature of the liquid was kept at 55 ° C. by heating the container in an oil bath. 8.5 g of silicon ethoxide and ammonia water (29% concentration)
6.5 g and 8 g of water were added, and the mixture was reacted for 5 hours with stirring. After drying and heating, the film thickness was adjusted to 138 nm. After the reaction, the reaction solution was diluted and washed with ethanol, filtered, and dried at 110 ° C. for 3 hours in a vacuum drier. Heat treatment using a dried rotary tubular oven alms 30 minutes at 650 ° C., to obtain a silica-coated powder A _1. The resulting silica dispersion state of the coated powder A ₁ was very good.

Second layer: titania coating After heat treatment, the silica-coated powder A obtained again₁ 10g
200 ml of ethanol, and disperse.
The temperature of the solution was maintained at 55 ° C. by heating in a bath. to this
8 g of titanium ethoxide is added and stirred. To this
A mixed solution of 30 ml of water and 11.5 g of water over 60 minutes
After dropping, let it react for 5 hours, dry the film thickness, heat treatment
Thereafter, the thickness was adjusted to 92 nm. After reaction ethanol
, Filtered, and dried in a vacuum dryer at 110 ° C for 3 hours.
Dried. After drying, heat treatment using a rotary tube furnace
Is applied at 650 ° C. for 30 minutes to obtain a silica-titania coated powder.
Body A _Two I got Obtained silica / titania coated powder A
_Two Had good dispersibility and each was a single particle. silica·
Titania coated powder A_Two Was bright red.

The peak wavelength of the spectral reflection curve of the coated powder of the above coating film, the reflectance at the peak wavelength, the refractive index and the film thickness of the coating film were measured by the following methods. (1) The spectral reflection curve was obtained by packing a powder sample into a glass holder using a spectrophotometer with an integrating sphere manufactured by JASCO Corporation and measuring the reflected light. The measurement was performed according to JISZ8722 (1982) and JISZ8732 (1988). (2) The refractive index and the film thickness were evaluated by measuring the results of measuring the spectral reflection curve of a sample having a film thickness under different conditions by fitting with a curve calculated by an instrument based on the equation of interference.

(Surface Hydrophobizing Treatment of Multilayer Film-Coated Powder) 10 g of the obtained silica-titania-coated powder A ₂ was added to an ethanol solution 200 g in which 0.2 g of silicon ethoxide was dissolved.
and the temperature of the solution was kept at 55 ° C. by heating the container in an oil bath. 3 g of aqueous ammonia (concentration of 29%) was added thereto, and the mixture was stirred for 3 hours, filtered, dried at 100 ° C. for 2 hours with a vacuum drier to obtain a hydrophobic multi-layered red-colored multilayer film-coated powder A ₃ . Obtained.

(Surface Hydrophobization Treatment of Scattering Particles) Average Particle Size 2
Silicon ethoxide 1.2 on titanium oxide particles of 00 nm
g was dissolved in 250 ml of a dissolved ethanol solution, and the vessel was heated in an oil bath to maintain the temperature of the solution at 55 ° C. 6 g of aqueous ammonia (29% concentration) is added to this,
After stirring for 3 hours, the mixture was filtered and dried in a vacuum dryer at 100 ° C. for 2 hours to obtain a hydrophobic titanium oxide powder.

Adhesive resin layer (polystyrene composite powder, made into toner) 100 g of styrene monomer was made lipophilic in the same manner as 100 g of red-colored multi-layer coated powder A ₃ lipophilized (hydrophobized) by the above-mentioned surface treatment method. The mixture was stirred with a high-speed stirrer until 45 g of titanium oxide was dispersed, and the mixture was homogenized. This mixture of styrene monomer and particles is treated with sodium n-dodecyl sulfate in distilled water 50.
The solution dissolved in 0 g was added while maintaining the temperature at 70 ° C. and stirring at a high speed, and stirred until the emulsified particles were sufficiently turned into fine particles. 10g of 10% ammonium persulfate aqueous solution
Was added and stirred for 4 hours to react. After completion of the reaction, the mixture is diluted with 2 liters of distilled water, and the supernatant is discarded by slant washing, and the precipitate is collected. The precipitate was dried on filter paper to obtain red polystyrene-coated powder A. The resulting red powder A was spherical and had a magnetization of 61 emu / g at a magnetic field of 10 KOe. Refractive index of the first and second coating layers and the adhesive resin layer,
Table 1 shows the film thickness, the peak wavelength of the spectral reflection curve of the powder, and the reflectance at the peak wavelength.

[0049]

[Table 1]

Example 2 First layer: silica coating Carbonyl iron powder manufactured by BASF (average particle size: 1.8 μm) 10
g was dispersed in 100 ml of ethanol, and the temperature of the liquid was kept at 55 ° C. by heating the container in an oil bath. 8.5 g of silicon ethoxide and ammonia water (29% concentration)
6.5 g and 8 g of water were added, and the mixture was reacted for 5 hours while stirring. After drying and heating, the film thickness was adjusted to 128 nm. After the reaction, the reaction solution was diluted and washed with ethanol, filtered, and dried at 110 ° C. for 3 hours in a vacuum drier. After drying,
The heat treatment performed for 30 minutes at 650 ° C. using a rotary tubular furnace to obtain silica-coated powder B _1. The resulting silica dispersion state of the coated powder B ₁ represents very good.

Second layer: titania coating 10 g of the obtained silica-coated powder B ₁ again after the heat treatment
Then, 200 ml of ethanol was added and dispersed, and the temperature of the liquid was maintained at 55 ° C. by heating the container in an oil bath. 8 g of titanium ethoxide is added thereto and stirred. A mixed solution of 30 ml of ethanol and 12 g of water was added dropwise thereto over 60 minutes, and the mixture was reacted for 5 hours.
It was adjusted to 4 nm. After the reaction, the reaction solution was diluted and washed with ethanol, filtered, and dried at 110 ° C. for 3 hours in a vacuum drier. After drying, heat treatment was performed using a rotary tube furnace at 65
Apply at 0 ° C for 30 minutes, and apply silica-titania-coated powder B ₂
I got The resulting silica-titania-coated powder B ₂ has good dispersibility and was an independent particle. The silica-titania-coated powder B ₂ was a bright red color. The refractive index and thickness of the coating film, the peak wavelength of the spectral reflection curve of the powder, and the reflectance at the peak wavelength were measured.

Third layer: silica coating 10 g of silica / titania coated powder B _{2 was} added to ethanol 1
The solution was dispersed in 00 ml, and the temperature of the solution was kept at 55 ° C. by heating the container in an oil bath. To this, 8.7 g of silicon ethoxide, 7.5 g of aqueous ammonia (29% concentration) and 8 g of water were added, and the mixture was reacted for 5 hours with stirring. After drying and heating, the film thickness was adjusted to 136 nm. .
After the reaction, the reaction solution was diluted and washed with ethanol, filtered, and dried at 110 ° C. for 3 hours in a vacuum drier. After drying, heat treatment was performed at 650 ° C. for 30 minutes using a rotary tube furnace, and silica
To obtain a titania-coated powder B _3. The resulting silica-titania dispersion state of the coated powder B ₃ was very good.

Fourth layer: titania coating After heat treatment, the obtained silica-coated powder B is again obtained._Three10g
200 ml of ethanol, and disperse.
The temperature of the solution was maintained at 55 ° C. by heating in a bath. to this
8.3 g of titanium ethoxide is added and stirred. To this
Over a period of 60 minutes
After dropping, let it react for 5 hours, dry the film thickness, heat treatment
Thereafter, the thickness was adjusted to 85 nm. After reaction ethanol
, Filtered, and dried in a vacuum dryer at 110 ° C for 3 hours.
Dried. After drying, heat treatment using a rotary tube furnace
Is applied at 650 ° C. for 30 minutes to obtain a silica-titania coated powder.
Body B _FourI got Obtained silica-titania coated powder B
_FourHad good dispersibility and each was a single particle. silica·
Titania coated powder B_FourWas bright red.

Adhesive resin layer (polystyrene composite powder) 100 g of styrene monomer and 45 g of lipophilic titanium oxide similarly to 100 g of red-colored multi-layer coated powder B ₄ lipophilized (hydrophobized) by the above-mentioned surface treatment method Was stirred with a high-speed stirrer until it was dispersed to make it uniform. This mixture of styrene monomer and particles was added to a solution of sodium n-dodecyl sulfate dissolved in 500 g of distilled water while maintaining the temperature at 70 ° C. while stirring at a high speed, and the mixture was stirred until the emulsified particles were sufficiently formed into fine particles.
10 g of a 10% aqueous solution of ammonium persulfate was added thereto, and the mixture was stirred and reacted for 4 hours. After completion of the reaction, distilled water 2
Dilute with liter and discard the upper solution by decantation and collect the precipitate. The precipitate was dried on filter paper to obtain red polystyrene-coated powder B. The resulting red powder was spherical and had a magnetization of 55 emu / g at a magnetic field of 10 koe. The refractive index and thickness of the coating film, the peak wavelength of the spectral reflection curve of the powder, and the reflectance at the peak wavelength were measured. The first
Table 2 shows the refractive indices, film thicknesses, peak wavelengths of the spectral reflection curves of the powder, and the reflectances at the peak wavelengths of the first to fourth layers and the adhesive resin layer.

[0055]

[Table 2]

Example 3 First layer: Resin layer first layer film 100 g of a red-colored multi-layer coated powder B similar to that of Example 2 in which 250 g of styrene monomer was previously made lipophilic (hydrophobicized) by the surface treatment method described above. The mixture was stirred with a high-speed stirrer until 15 g of the lipophilic titanium oxide was dispersed, and the mixture was homogenized. A mixture of this styrene monomer and particles, in which 8 g of sodium n-dodecyl sulfate was dissolved in 100 g of distilled water, was introduced while maintaining the temperature at 70 ° C. and stirring at a high speed.
The mixture was stirred until the emulsified particles were sufficiently reduced to fine particles. This one
2 g of a 0% ammonium persulfate aqueous solution was added to initiate a polymerization reaction, and the mixture was stirred and reacted for 4 hours. After the reaction,
Dilute with 2 liters of distilled water, discard the upper solution by slant washing, and collect the precipitate. The precipitate was dried on a filter paper to give a red polystyrene-coated powder C _1.

[0057] 2-layer: A mixture of the second layer film resin layer styrene monomer 250g and particles C _1, and stirred at a high speed stirrer titanium oxide 10g was lipophilized until o dispersion was homogenized. Sodium n-dodecyl sulfate 8g
Was dissolved in 100 g of distilled water while the temperature was maintained at 70 ° C., and the solution was charged with high-speed stirring, followed by stirring until the emulsified particles were sufficiently made fine. To this, 2 g of a 10% aqueous solution of ammonium persulfate was added, added dropwise with a burette over 30 minutes, and stirred for 4 hours to cause a reaction. After completion of the reaction, distilled water 2
Dilute with liter and discard the upper solution by decantation and collect the precipitate. The precipitate was dried on filter paper to obtain red-white polystyrene-coated powder C. Table 3 shows the results of measuring the thickness of the coated powder, the peak wavelength of the spectral reflection curve of the powder, and the reflectance at the peak wavelength.

[0058]

[Table 3]

Comparative Example 1 First layer: silica coating Carbonyl iron powder manufactured by BASF (average particle size: 1.8 μm) 10
g was dispersed in 100 ml of ethanol, and the temperature of the liquid was kept at 55 ° C. by heating the container in an oil bath. 6.5 g of silicon ethoxide and ammonia water (29% concentration)
6.5 g was added, and the mixture was reacted for 5 hours with stirring. After drying and heating, the film thickness was adjusted to 96 nm.
After the reaction, the reaction solution was diluted and washed with ethanol, filtered, and dried at 110 ° C. for 3 hours in a vacuum drier. Heat treatment using a dried rotary tubular oven alms 30 minutes at 650 ° C., to obtain a silica-coated powder D _1. The resulting silica dispersion state of the coated powder D ₁ was very good.

Second layer: titania coating After heat treatment, again, 10 g of the obtained silica-coated powder D ₁
Then, 200 ml of ethanol was added and dispersed, and the temperature of the liquid was maintained at 55 ° C. by heating the container in an oil bath. To this, 7.3 g of titanium ethoxide is added and stirred. A mixed solution of 30 ml of ethanol and 7.3 g of water was added dropwise thereto over 60 minutes, reacted for 5 hours, dried, heat-treated, and adjusted to 72 nm. After the reaction, the reaction solution was diluted and washed with ethanol, filtered, and dried at 110 ° C. for 3 hours in a vacuum drier. After drying, heat treatment was performed at 650 ° C. for 30 minutes using a rotary tube furnace to obtain silica-titania-coated powder D ₂ . Obtained silica / titania coated powder D
₂ had good dispersibility and each was a single particle. silica·
Titania-coated powder D ₂ was a green color. The refractive index and thickness of the coating film, the peak wavelength of the spectral reflection curve of the powder, and the reflectance at the peak wavelength were measured.

Adhesive resin layer (polystyrene composite powder) 100 g of styrene monomer and 25 g of lipophilic titanium oxide similarly to 100 g of red-colored multi-layer coated powder D ₂ previously made lipophilic (hydrophobized) by the above-mentioned surface treatment method Was stirred with a high-speed stirrer until it was dispersed to make it uniform. This mixture of styrene monomer and particles was added to a solution of sodium n-dodecyl sulfate dissolved in 500 g of distilled water while maintaining the temperature at 70 ° C. while stirring at a high speed, and the mixture was stirred until the emulsified particles were sufficiently formed into fine particles.
10 g of a 10% aqueous solution of ammonium persulfate was added thereto, and the mixture was stirred and reacted for 4 hours. After completion of the reaction, distilled water 2
Dilute with liter and discard the upper solution by decantation and collect the precipitate. The precipitate was dried on filter paper to obtain green polystyrene-coated powder D. The resulting green powder D was spherical and had a magnetization of 65 emu / g at a magnetic field of 10 koe. The refractive index and thickness of the coating film, the peak wavelength of the spectral reflection curve of the powder, and the reflectance at the peak wavelength were measured. Refractive index, film thickness of the first and second layers and the adhesive resin layer,
Table 4 shows the reflectance at the peak wavelength of the spectral reflection curve of the powder.
Shown in

[0062]

[Table 4]

Comparative Example 2 (When a magnetic substance and a pigment were simply mixed) Lead red (red pigment) reflectance (average particle size 0.2 μm, reflection peak 750 μm)
m, reflectivity 73%), and a carbonyl iron powder (average particle size 1.8 μm) manufactured by BASF in a weight ratio of 25 g: 25 g.
And thoroughly homogenized. This powder is mixed with distilled water 60
90 g of a styrene monomer and 10 g of butylene acrylate were added to 0 g, and the mixture was heated and stirred to 70 ° C., further placed in a solution in which sodium lauryl sulfate was added and emulsified, and sufficiently mixed by high-speed stirring. Add an aqueous solution of ammonium persulfate 1
0% was added to initiate a polymerization reaction, and the mixture was stirred and reacted for 4 hours. After completion of the reaction, the mixture was diluted with 2 liters of distilled water, the upper solution was discarded by slant washing, and the precipitate was dried on filter paper.
Pigment and iron powder were all covered with polystyrene to obtain an integrated spherical powder E. This polystyrene-coated powder E was dark red, and had a reflection peak of 750 nm and a reflectance of 37%. The magnetization of this powder at a magnetic field of 10 kOe is 7
It was 5 emu / g.

As can be seen from the comparison between Table 1 and Tables 2 and 3, coating layers having different refractive indices are alternately laminated on the surfaces of the base particles, and the thickness is controlled to 600 to 800 nm.
By adjusting the peak of the reflection spectrum of each coating layer during the period, the red composite material powder of the present invention can be obtained. Further, as can be seen from the comparison between Examples 1, 2, and 3, and Comparative Example 2, simply mixing the pigment, the base particles, and the binder resin does not improve the color. It has been confirmed that even in the case of a magnetic toner, it is necessary to color the base particles according to the present invention as in the example, in order to obtain a red toner having excellent color.

[0065]

According to the red toner of the present invention and the method for producing the same, color composite powders used for various purposes such as color magnetic toners for copiers and printers and color toners for printing are produced. The present invention provides a red toner which can perform an excellent combined function even in a one-component developing system, and an efficient and highly accurate manufacturing method of the toner. The obtained red toner retains excellent performance that replaces the conventional toner and can provide a stable color tone even during long-term storage. Dispersibility is good, interference reflection is large, it is possible to achieve a clear color, and the base particles can be changed according to the application and purpose, for example, when the base is made of a magnetic material, it becomes a magnetic toner, When a dielectric or conductor is used, a toner for an ink jet printer, an electrostatic recording device, or the like can be provided, which greatly contributes to the industry.

[Brief description of the drawings]

FIG. 1 is a graph showing a spectral waveform of a reflection intensity of each unit film constituting a multilayer film of a powder colored in a red color system.

FIG. 2 is a schematic cross-sectional view showing one embodiment of a red magnetic toner of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Base particle 2 Metal compound film 3 Metal compound film 4 Adhesive resin layer film

Claims (10)

[Claims] 1. A coating film comprising a plurality of coating layers in which a coating having a large refractive index and a coating having a small refractive index are laminated adjacently on the surface of a base particle, and an adhesive resin layer in which pigments and dyes are dispersed outside the coating layer. And a reflection spectrum having a peak between 600 and 800 nm. 2. When the refractive index of the substrate particles is larger than the refractive index of the first layer coating in contact with the substrate surface, the substrate particles have an even number of layers, and the refractive index of the substrate particles is the refractive index of the first layer coating. 2. The red toner according to claim 1, wherein the toner has an odd number of layers when the ratio is smaller than the ratio. 3. The red toner according to claim 1, wherein the base particles are a magnetic substance, a dielectric substance, or a conductor. 4. The pigment has a content of 5 to 60 vol% in the adhesive resin layer.
2. The red toner according to claim 1, wherein the toner is dispersed and contained in the range described above. 5. The adhesive resin layer has a pigment content of 5 to 60 v.
5. The red toner according to claim 4, wherein the toner has a two-layer structure of an inner layer in a range of 0% by volume and an outer layer in a range of 0 to 15% by volume of a pigment. 6. A method for producing a red toner comprising a plurality of coating layers having different refractive indices on the surface of a base particle and an adhesive resin layer in which a pigment and a dye are dispersed outside the coating layer. Forming a plurality of layers in which a film having a large refractive index and a film having a small refractive index are stacked side by side on the surface of
A method for producing a red toner, wherein the conditions of the base particles and the coating layer are set so as to show a reflection spectrum having a peak between 00 nm. 7. When the refractive index of the substrate particles is larger than the refractive index of the first layer coating in contact with the surface of the substrate, an even layer coating is formed, and the refractive index of the substrate particles is the refractive index of the first layer coating. 7. The method according to claim 6, wherein an odd-numbered layer is formed when the ratio is smaller than the ratio. 8. The method for producing a red toner according to claim 6, wherein the base particles are made of a magnetic material, a dielectric material or a conductor. 9. The pigment is incorporated in the adhesive resin layer in an amount of 5 to 60% by volume.
The method for producing a red-colored toner according to claim 6, wherein the toner is dispersed and contained within the range of. 10. An adhesive resin layer containing 5 to 60% by volume of a pigment.
The method for producing a red-colored toner according to claim 9, wherein the toner has a two-layer structure of an inner layer in the range of 0 to 15% and an outer layer in the range of 0 to 15% by volume of the pigment.