Resin Particle Combination

Abstract

The present invention relates to a resin particle combination, comprising fluorescent resin particles containing a fluorescent colorant and colored resin particles containing a colored colorant, wherein the volume average particle size of the fluorescent resin particles is larger than the volume average particle size of the colored resin particles, and the average roundness of the fluorescent resin particles is greater than 0.93.

Description

Technical Field

[0001] The present invention relates to a resin particle combination. Background Art

[0002] Resin particles have various application purposes, one of which is a toner in electrophotography. As a conventional toner, the toner described in Japanese Patent Application Laid-Open No. 2017-3818 is well known.

[0003] Japanese Patent Application Laid-Open No. 2017-3818 discloses a toner containing a binder resin and a colorant, wherein the colorant contains a coloring pigment and a fluorescent dye, and the mass-based contents of the coloring pigment and the fluorescent dye in the toner are W and W, respectively. G , W F When the above W G and the above W F Satisfies the following formula (1),

[0004] W G ×0.5>W F >W G ×0.025 (1)

[0005] Assume that the absorption peak wavelength of the above coloring pigment is P G , let the peak wavelength of the fluorescent dye be P F When the above P G and the above P F The following formula (2) is satisfied.

[0006] P G <P F (2) Summary of the invention

[0007] The technical problem to be solved by the present invention is to provide a resin particle combination, which has excellent color reproduction of the image obtained compared with the case where the combination has fluorescent resin particles containing a fluorescent colorant and colored resin particles containing a colored colorant, the volume average particle size of the above-mentioned fluorescent resin particles is less than the volume average particle size of the above-mentioned colored resin particles, or the average roundness of the above-mentioned fluorescent resin particles is less than 0.93.

[0008] Specific means for solving the above technical problems include the following methods.

[0009] According to the first embodiment of the present invention, a resin particle combination is provided, which has fluorescent resin particles containing a fluorescent colorant and colored resin particles containing a colored colorant, the volume average particle size of the fluorescent resin particles is larger than the volume average particle size of the colored resin particles, and the average roundness of the fluorescent resin particles is greater than 0.93.

[0010] According to a second aspect of the present invention, there is provided the resin particle combination according to the first aspect, wherein the volume ratio of resin particles having a particle size of 4 μm or less contained in the fluorescent resin particles is 6% or less.

[0011] According to the third aspect of the present invention, there is provided a resin particle combination as described in the first or second aspect, wherein the value of (the volume average particle size of the fluorescent resin particles) - (the volume average particle size of the colored resin particles) is greater than 0.3 μm.

[0012] According to a fourth aspect of the present invention, there is provided the resin particle combination according to any one of the first to third aspects, wherein the fluorescent colorant is a fluorescent dye.

[0013] According to a fifth aspect of the present invention, there is provided the resin particle combination according to the fourth aspect, wherein the fluorescent dye includes a fluorescent dye having a maximum fluorescence wavelength in the range of 580 nm to 650 nm.

[0014] Effects of the Invention

[0015] According to the above-mentioned first scheme, a resin particle combination is provided, and the color reproducibility of the obtained image is compared with the case where the combination has fluorescent resin particles containing a fluorescent colorant and colored resin particles containing a colored colorant, the volume average particle size of the above-mentioned fluorescent resin particles is less than the volume average particle size of the above-mentioned colored resin particles, or the average roundness of the above-mentioned fluorescent resin particles is less than 0.93.

[0016] According to the second aspect, there is provided a resin particle combination that can produce an image with better color reproducibility than when the volume ratio of the resin particles having a particle size of 4 μm or less contained in the fluorescent resin particles is greater than 6%.

[0017] According to the third scheme, a resin particle combination is provided, wherein the color reproducibility of the obtained image is better than that in the case where the value of (the volume average particle size of the fluorescent resin particles) - (the volume average particle size of the colored resin particles) is less than 0.3 μm.

[0018] According to the fourth aspect, there is provided a resin particle combination, wherein the color reproducibility of the obtained image is more excellent than in the case where the fluorescent colorant is a fluorescent pigment.

[0019] According to the fifth aspect, there is provided a resin particle combination, which can obtain an image with better color reproducibility than when the fluorescent dye is a fluorescent dye that does not have a maximum fluorescence wavelength in the wavelength range of 580 nm to 650 nm. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic structural diagram showing an example of an image forming apparatus used in this embodiment.

[0021] Figure 2 This is a schematic structural diagram showing an example of a process cartridge used in this embodiment.

[0022] Figure 3 An example of the spectrum of each color of fluorescent color is shown. The vertical axis represents the fluorescence intensity, and the horizontal axis represents the wavelength. It should be noted that "mμ" = "nm". DETAILED DESCRIPTION

[0023] In the present specification, when referring to the amount of each component in a composition, if two or more substances corresponding to each component exist in the composition, unless otherwise stated, it means the total amount of the two or more substances present in the composition.

[0024] In the present specification, “toner for developing an electrostatic image” is also simply referred to as “toner”, and “developer for developing an electrostatic image” is also simply referred to as “developer”.

[0025] Next, an embodiment as an example of the present invention will be described.

[0026] <Resin Particle Combination>

[0027] The resin particle combination of this embodiment comprises fluorescent resin particles containing a fluorescent colorant and colored resin particles containing a colored colorant, the volume average particle size of the fluorescent resin particles being larger than the volume average particle size of the colored resin particles, and the average roundness of the fluorescent resin particles being greater than 0.93.

[0028] Fluorescent resin particles are resin particles that contain fluorescent colorants, and when the electrons excited by absorbing the irradiation energy in the short wavelength region from ultraviolet light to visible light contained in the incident light return to the ground state, the energy released makes it show a spectral reflectance>1 in a specific wavelength region. The short wavelength component from ultraviolet light to visible light has the property of being easily reflected or diffused, and has the characteristic that the color reproducibility is easily changed due to color mixing or whitening. In addition, since fluorescent colors appear brighter (brighter) than non-fluorescent colors, sometimes the difference is highlighted in terms of the reduction in color reproducibility due to color turbidity (color turbidity is caused by the overlap of unfixed images or the disordered configuration and scattering of resin particles in multiple transfers). More specifically, fluorescent colors are colors that appear bright to the human eye, and therefore have the characteristic of being easily noticed by the eye compared to non-fluorescent colors. On the other hand, in the process before the toner image is fixed, various treatments are performed using the device or its components, for example, two or more toners are overlapped or transferred in an overlapping manner on the transfer. During this process, unfixed toner inevitably moves.

[0029] When the toner moves, it is easy to be noticeable if the toner is misplaced or scattered. For example:

[0030] Fluorescent toner scatters more easily than non-fluorescent toner scatters.

[0031] In the case of a color produced by overlapping two or more toners, if a fluorescent color toner is included, compared with a case where the fluorescent color toner is not included, a portion where the color reproduction is not as ideal due to a disordered arrangement of the toners, etc. is more conspicuous (for example, taking a solid image as an example, it is more difficult to produce a beautiful and uniform solid image using a fluorescent color toner than a solid image produced using a non-fluorescent color toner and a non-fluorescent color toner); etc.

[0032] By making the volume average particle size of the fluorescent resin particles larger than the volume average particle size of the above-mentioned colored resin particles, color mixing caused by overlapping of unfixed images or disordered configuration and scattering of resin particles in multiple transfers can be suppressed; and by making the average roundness of the fluorescent resin particles be greater than 0.93, disordered configuration and scattering of the above-mentioned fluorescent resin particles themselves can be suppressed, and the color rendering properties are also good, so the color reproduction of the obtained image is excellent.

[0033] The resin particle combination according to this embodiment will be described in detail below.

[0034] -Relationship between the volume average particle size of fluorescent resin particles and the volume average particle size of colored resin particles-

[0035] In the resin particle combination of this embodiment, the volume average particle size of the above-mentioned fluorescent resin particles is larger than the volume average particle size of the above-mentioned colored resin particles. From the aspects of color reproduction, image quality and fluorescence intensity, the value of (volume average particle size of the above-mentioned fluorescent resin particles) - (volume average particle size of the above-mentioned colored resin particles) is preferably greater than 0.1 μm, more preferably greater than 0.3 μm, further preferably greater than 0.5 μm, and particularly preferably greater than 0.7 μm.

[0036] In addition, from the perspective of color reproducibility, image quality and fluorescence intensity, the upper limit of the value of (volume average particle size of the above-mentioned fluorescent resin particles) - (volume average particle size of the above-mentioned colored resin particles) is preferably less than 5.0 μm, more preferably less than 3.0 μm, further preferably less than 2.5 μm, and particularly preferably less than 2.0 μm.

[0037] The volume average particle size (D 50v ), from the aspects of color reproducibility, image quality and fluorescence intensity, it is preferably greater than 2 μm and less than 10 μm, more preferably greater than 3 μm and less than 8 μm, further preferably greater than 4 μm and less than 7 μm, and particularly preferably greater than 5.0 μm and less than 6.5 μm.

[0038] As the volume average particle size (D 50v ), from the aspects of color reproducibility, image quality and fluorescence intensity, it is preferably greater than 2 μm and less than 10 μm, more preferably greater than 3 μm and less than 8 μm, further preferably greater than 3.5 μm and less than 7 μm, particularly preferably greater than 4.0 μm and less than 6.0 μm, and most preferably greater than 4.0 μm and less than 5.0 μm.

[0039] The volume average particle size of the fluorescent resin particles and the volume average particle size of the colored resin particles were measured using Coulter Multisizer II (manufactured by Beckman Coulter) and ISOTON-II (manufactured by Beckman Coulter) for the electrolyte.

[0040] In the measurement, 0.5 mg to 50 mg of the measurement sample is added to 2 ml of a 5 mass % aqueous solution of a surfactant (preferably sodium alkylbenzene sulfonate) as a dispersant, and then added to 100 ml to 150 ml of the electrolyte.

[0041] The electrolyte in which the sample was suspended was dispersed by an ultrasonic disperser for 1 minute, and the particle sizes of particles ranging from 2 μm to 60 μm were measured by Coulter Multisizer II using an aperture of 100 μm. The number of particles sampled was 50,000.

[0042] The measured particle diameters were plotted as a cumulative distribution based on volume from the smaller diameter side, and the particle diameter at the cumulative 50% point was defined as the volume average particle diameter D 50v .

[0043] -Average roundness of fluorescent resin particles and average roundness of colored resin particles-

[0044] In the resin particle combination of this embodiment, the average roundness of the fluorescent resin particles is greater than 0.93. From the perspective of color reproducibility, image quality and fluorescence intensity, it is preferably greater than 0.93 and less than 0.98, more preferably greater than 0.940 and less than 0.975, and particularly preferably greater than 0.950 and less than 0.970.

[0045] The average circularity of the colored resin particles is not particularly limited, but is preferably 0.93 or more, more preferably 0.93 or more and 0.98 or less, further preferably 0.940 or more and 0.975 or less, and particularly preferably 0.950 or more and 0.970 or less, from the perspective of color reproducibility, image quality, and fluorescence intensity.

[0046] The roundness of the resin particles in this embodiment refers to the value obtained by (the circumference of a circle having the same area as the particle projection image) ÷ (the circumference of the particle projection image), and the average roundness of the resin particles refers to the roundness of 50% of the points accumulated from the small roundness side in the distribution of roundness. The average roundness of the resin particles is obtained by analyzing at least 3,000 resin particles using a flow particle image analyzer.

[0047] The average circularity of the resin particles can be controlled by adjusting the stirring speed of the dispersion, the temperature of the dispersion or the holding time in the fusion / merging (fusion / unification) step, for example, when the resin particles are produced by the agglomeration / merging method (agglomeration unification method).

[0048] - Volume ratio of resin particles having a particle size of 4 μm or less contained in fluorescent resin particles -

[0049] In the resin particle combination of this embodiment, from the aspects of color reproducibility, image quality and fluorescence intensity, the volume proportion of resin particles with a particle size of less than 4 μm contained in the above-mentioned fluorescent resin particles is preferably less than 6%, more preferably less than 5%, further preferably less than 4%, and particularly preferably less than 3.5%.

[0050] The method for measuring the volume ratio of resin particles having a particle size of 4 μm or less contained in the fluorescent resin particles is as follows: the volume-based particle size distribution is measured by the same method as the volume average particle size of the fluorescent resin particles, and the volume ratio of resin particles having a particle size of 4 μm or less is calculated.

[0051] Hereinafter, when "resin particles" are referred to without explicitly stating either fluorescent resin particles or colored resin particles, the description refers to both fluorescent resin particles and colored resin particles.

[0052] The resin particle combination of this embodiment may include two or more types of fluorescent resin particles, or may include two or more types of colored resin particles.

[0053] Examples of the colored resin particles include yellow resin particles, magenta resin particles, cyan resin particles, black resin particles, red resin particles, green resin particles, blue resin particles, orange resin particles, and violet resin particles.

[0054] Among them, in the resin particle combination of this embodiment, from the aspect of easily forming a full-color image, as the above-mentioned colored resin particles, it is preferred to have yellow resin particles, magenta resin particles and cyan resin particles, and as the above-mentioned colored resin particles, it is more preferred to have yellow resin particles, magenta resin particles, cyan resin particles and black resin particles.

[0055] The fluorescent resin particles contain a binder resin, a fluorescent colorant, and, if necessary, a release agent and other additives, and preferably contain a binder resin, a fluorescent colorant, and a release agent.

[0056] The colored resin particles contain a binder resin, a colorant, and, if necessary, a release agent and other additives, preferably a binder resin, a colorant, and a release agent.

[0057] -Fluorescent colorant-

[0058] The fluorescent resin particles contain a fluorescent colorant.

[0059] In addition, the colored resin particles preferably do not contain a fluorescent colorant.

[0060] The fluorescent colorant may be any colorant that exhibits fluorescence, and is preferably a colorant that exhibits fluorescence in the visible light region (wavelength 380 nm to 760 nm). The light that excites the fluorescent colorant is not particularly limited, but preferably contains at least visible light or ultraviolet light, and more preferably contains at least ultraviolet light.

[0061] Furthermore, the fluorescent colorant may be a fluorescent pigment or a fluorescent dye, and is preferably a fluorescent dye.

[0062] It should be noted that, in the present embodiment, "pigment" refers to a colorant whose solubility in 100 g of water at 23°C and in 100 g of cyclohexanone at 23°C are both less than 0.1 g, and "dye" refers to a colorant whose solubility in 100 g of water at 23°C or in 100 g of cyclohexanone at 23°C is 0.1 g or more.

[0063] In addition, the color of the fluorescent colorant is not particularly limited and can be appropriately selected as needed.

[0064] Examples of the fluorescent colorant include a fluorescent pink colorant, a fluorescent red colorant, a fluorescent orange colorant, a fluorescent yellow colorant, a fluorescent green colorant, and a fluorescent violet colorant.

[0065] Among them, fluorescent pink colorants, fluorescent red colorants, fluorescent orange colorants, fluorescent yellow colorants or fluorescent green colorants are preferred, fluorescent pink colorants, fluorescent yellow colorants or fluorescent green colorants are more preferred, and fluorescent pink colorants are particularly preferred.

[0066] In addition, the fluorescent resin particles are preferably fluorescent pink resin particles, fluorescent red resin particles, fluorescent orange resin particles, fluorescent yellow resin particles, fluorescent green resin particles, fluorescent purple resin particles, fluorescent vermilion resin particles or fluorescent water-colored resin particles, more preferably fluorescent pink resin particles, fluorescent yellow resin particles or fluorescent green resin particles, and particularly preferably fluorescent pink resin particles.

[0067] The fluorescence peak wavelength of the fluorescent colorant under the spectral reflectance can be appropriately selected according to the desired color. For example, when it is desired to show fluorescent pink as the color, it is preferably 560nm to 670nm, and more preferably 580nm to 650nm.

[0068] In the fluorescent colorant, from the viewpoint of the graininess of the image, the value of the spectral reflectance at the fluorescence peak wavelength is preferably 100% or more, more preferably 105% or more, and particularly preferably 110% or more.

[0069] As the fluorescent colorant, a known fluorescent colorant can be used, and specific examples thereof include Basic Red 1 (Rhodamine 6G), Basic Red 1:1, Basic Red 2, Basic Red 12, Basic Red 13, Basic Red 14, Basic Red 15, Basic Red 36, Basic Violet 7, Basic Violet 10 (Rhodamine B), Basic Violet 11 (Rhodamine 3B), Basic Violet 11:1 (Rhodamine A), Basic Violet 15, Basic Violet 16, Basic Violet 27, Pigment Yellow 101 ... Acid Yellow 1, Basic Yellow 2, Basic Yellow 9, Basic Yellow 24, Basic Yellow 40, Basic Orange 15, Basic Orange 22, Basic Blue 1, Basic Blue 3, Basic Blue 7, Basic Blue 9, Basic Blue 45, Basic Green 1, Acid Yellow 3, Acid Yellow 7, Acid Yellow 73, Acid Yellow 87, Acid Yellow 184, Acid Yellow 245, Acid Yellow 250, Acid Red 51, Acid Red 52, Acid Red 57, Acid Red 77, Acid Red 87, Acid Red 89, Acid Red 92, Acid Blue 9, Acid Black 2, Solvent Yellow 43, Solvent Yellow 44, Solvent Yellow 85, Solvent Yellow 98, Solvent Yellow 116, Solvent Yellow 131, Solvent Yellow 145, Solvent Yellow 160:1, Solvent Yellow 172, Solvent Yellow 185, Solvent Yellow 195, Solvent Yellow 196, Solvent Orange 63, Solvent Orange 112, Solvent Red 49, Solvent Red 149, Solvent Red 175, Solvent Red 196, Solvent Red 197, Solvent Blue 5, Solvent Green 5, Solvent Green 7, Direct Yellow 27 , Direct Yellow 85, Direct Yellow 96, Direct Orange 8, Direct Red 2, Direct Red 9, Direct Blue 22, Direct Blue 199, Direct Green 6, Disperse Yellow 11, Disperse Yellow 82, Disperse Yellow 139, Disperse Yellow 184, Disperse Yellow 186, Disperse Yellow 199, Disperse Yellow 202, Disperse Yellow 232, Disperse Orange 11, Disperse Orange 32, Disperse Red 58, Disperse Red 274, Disperse Red 277, Disperse Red 303, Disperse Blue 7, Reaction Yellow 78, Vat Red 41, etc.

[0070] These fluorescent colorants can be selected from one or more according to the desired color. For example, when it is desired to express fluorescent pink, it is preferably at least one fluorescent colorant selected from the group consisting of Basic Red 1 (Rhodamine 6G), Basic Red 1:1, Basic Red 2, Basic Red 12, Basic Red 13, Basic Red 14, Basic Red 15, Basic Red 36, Basic Violet 7, Basic Violet 10 (Rhodamine B), Basic Violet 11 (Rhodamine 3B), Basic Violet 11:1 (Rhodamine A), Basic Violet 15, Basic Violet 16 and Basic Violet 27.

[0071] In addition, from the viewpoint of fluorescence intensity and graininess of an image, the fluorescent colorant preferably contains a fluorescent colorant having a xanthene structure, a naphthalene structure or a triarylmethane structure, and more preferably contains a fluorescent colorant having a xanthene structure.

[0072] In addition, the xanthene structure is preferably a rhodamine structure, a fluorescein structure or an eosin structure, and is more preferably a rhodamine structure.

[0073] The fluorescent resin particles may contain one fluorescent colorant alone or two or more fluorescent colorants in combination.

[0074] The content of the fluorescent colorant is preferably 0.2% by mass to 5% by mass, more preferably 0.2% by mass to 3% by mass, and particularly preferably 0.2% by mass to 2% by mass, based on the entire resin particles, from the viewpoint of fluorescence intensity and image graininess.

[0075] -Colored colorants-

[0076] The above-mentioned colored resin particles contain a colored colorant.

[0077] In addition, from the viewpoint of color reproducibility, the fluorescent resin particles preferably contain a fluorescent colorant and a colored colorant.

[0078] The colored colorant in the present embodiment refers to a colorant that can absorb any light in the visible light region (wavelength of 380 nm to 760 nm).

[0079] As the colored colorant, a known colorant is used.

[0080] In addition, the colored colorant is preferably a colorant that does not exhibit fluorescence in the visible light region.

[0081] The colored colorant may be a pigment or a dye, but is preferably a pigment.

[0082] Specific examples of the colored colorant include CI Pigment Red 1, CI Pigment Red 2, CI Pigment Red 3, CI Pigment Red 4, CI Pigment Red 5, CI Pigment Red 6, CI Pigment Red 7, CI Pigment Red 8, CI Pigment Red 9, CI Pigment Red 10, CI Pigment Red 11, CI Pigment Red 12, CI Pigment Red 14, CI Pigment Red 15, CI Pigment Red 16, CI Pigment Red 17, CI Pigment Red 18, CI Pigment Red 21, CI Pigment Red 22, CI Pigment Red 23, CI Pigment Red 31, CI Pigment Red 32, CI Pigment Red 38, CI Pigment Red 41, CI Pigment Red 42, CI Pigment Red 43, CI Pigment Red 44, CI Pigment Red 45, CI Pigment Red 46, CI Pigment Red 47, CI Pigment Red 48, CI Pigment Red 49, CI Pigment Red 50, CI Pigment Red 51, CI Pigment Red 52, CI Pigment Red 53, CI Pigment Red 54, CI Pigment Red 55, CI Pigment Red 56, CI Pigment Red 57, CI Pigment Red 58, CI Pigment Red 59, CI Pigment Red 60, CI Pigment Red 61, CI Pigment Red 62, CI Pigment Red 63, CI Pigment Red 64, CI Pigment Red 65 CI Pigment Red 48, CI Pigment Red 48:1, CI Pigment Red 48:2, CI Pigment Red 48:3, CI Pigment Red 48:4, CI Pigment Red 49, CI Pigment Red 52, CI Pigment Red 53:1, CI Pigment Red 54, CI Pigment Red 57:1, CI Pigment Red 58, CI Pigment Red 60:1, CI Pigment Red 63, CI Pigment Red 64:1, CI Pigment Red 68, CI Pigment Red 81:1, CI Pigment Red 81:4, CI Pigment Red 83, CI Pigment Red 88, CI Pigment Red 89, CI Pigment Red 112, CI Pigment Red 114, CI Pigment Red 12 2. CI Pigment Red 123, CI Pigment Red 144, CI Pigment Red 146, CI Pigment Red 149, CI Pigment Red 150, CI Pigment Red 166, CI Pigment Red 170, CI Pigment Red 176, CI Pigment Red 177, CI Pigment Red 178, CI Pigment Red 179, CI Pigment Red 184, CI Pigment Red 185, CI Pigment Red 187, CI Pigment Red 202, CI Pigment Red 206, CI Pigment Red 207, CI Pigment Red 208, CI Pigment Red 209, CI Pigment Red 210, CI Pigment Red 220, CI Pigment Red 221, CI Pigment Red 222 CI Pigment Red 238, CI Pigment Red 242, CI Pigment Red 245, CI Pigment Red 253, CI Pigment Red 254, CI Pigment Red 255, CI Pigment Red 256, CI Pigment Red 258, CI Pigment Red 264, CI Pigment Red 266, CI Pigment Red 269, CI Pigment Red 282, etc.; Pigment Violet 19; Magenta Pigment; CI Solvent Red 1, CI Solvent Red 3, CI Solvent Red 8, CI Solvent Red 23, CI Solvent Red 24, CI Solvent Red 25, CI Solvent Red 27, CI Solvent Red 30, CI Solvent Red 49, CI Solvent Red 52, CI Solvent Red 58, CICI Solvent Red 63, CI Solvent Red 81, CI Solvent Red 82, CI Solvent Red 83, CI Solvent Red 84, CI Solvent Red 100, CI Solvent Red 109, CI Solvent Red 111, CI Solvent Red 121, CI Solvent Red 122, CI Disperse Red 9, CI Basic Red 1, CI Basic Red 2, CI Basic Red 9, CI Basic Red 12, CI Basic Red 13, CI Basic Red 14, CI Basic Red 15, CI Basic Red 17, CI Basic Red 18, CI Basic Red 22, CI Basic Red 23, CI Basic Red 24, CI Basic Red 27, CI Basic Red 29, CI Basic Red 32, CI Basic Red 34, CI Basic Red 35, CI Basic Red 36, CI Basic Red 3 7. CI Basic Red 38, CI Basic Red 39, CI Basic Red 40 and other magenta dyes; red iron oxide, cadmium red, red lead, mercury sulfide, permanent red 4R, litho red, pyrazolone red, watching red, calcium salt, lake red D, brilliant carmine 6B, azure lake, rhodamine lake B, alizarin lake, brilliant carmine 3B, carbon black, chrome yellow, Hansa yellow, benzidine yellow, vat yellow, quinoline yellow, pigment yellow, permanent orange GTR, pyrazolone orange, sulfur-resistant orange, brilliant carmine 3B, brilliant carmine 6B, DuPont oil red, lake red C, aniline blue, ultramarine blue, oil-soluble blue, methylene blue chloride, phthalocyanine blue, pigment blue, phthalocyanine green, malachite green oxalate and other pigments or dyes. Solid solution pigments (pigments obtained by dissolving two or more pigments to change their crystal structure) are also suitable. Specifically, different combinations of quinacridone substituents (unsubstituted quinacridone PV19 and PR122, PV19 and PR202, etc.) can be cited as an example.

[0083] Other coloring agents can be suitably selected according to the desired color. For example, in the case of wishing to show fluorescent pink, a fuchsin pigment can be cited as an example. Wherein it is suitable to be a solid solution pigment. As a fluorescent color, if a bright color or a dark color is produced even if it is the same hue, then the performance is good, and by using a solid solution pigment, the performance tends to improve.

[0084] The colored colorants may be used alone or in combination of two or more.

[0085] The coloring agent may be a coloring agent that has been subjected to surface treatment as required, or may be used in combination with a dispersant. In addition, two or more coloring agents may be used in combination.

[0086] The content of the colored colorant in the colored resin particles is preferably 0.1% by mass to 30% by mass, more preferably 0.2% by mass to 20% by mass, and particularly preferably 0.5% by mass to 10% by mass, relative to the entire colored resin particles, from the perspective of color reproducibility.

[0087] The content of the colored colorant in the fluorescent resin particles is preferably 0.1% by mass to 30% by mass, more preferably 0.2% by mass to 15% by mass, and particularly preferably 0.5% by mass to 5% by mass, relative to the entire fluorescent resin particles, from the perspective of fluorescence intensity and color reproducibility.

[0088] - Adhesive resin -

[0089] Examples of the adhesive resin include vinyl resins formed by homopolymers of the following monomers or copolymers of two or more of these monomers: styrenes (e.g., styrene, p-chlorostyrene, α-methylstyrene, etc.), (meth)acrylates (e.g., methyl acrylate, ethyl acrylate, n-propyl acrylate, n-butyl acrylate, lauryl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, lauryl methacrylate, 2-ethylhexyl methacrylate, etc.), ethylenically unsaturated nitriles (e.g., acrylonitrile, methacrylonitrile, etc.), vinyl ethers (e.g., vinyl methyl ether, vinyl isobutyl ether, etc.), vinyl ketones (e.g., vinyl methyl ketone, vinyl ethyl ketone, vinyl isopropenyl ketone, etc.), olefins (e.g., ethylene, propylene, butadiene, etc.), and the like.

[0090] Examples of the adhesive resin include non-vinyl resins such as epoxy resins, polyester resins, polyurethane resins, polyamide resins, cellulose resins, polyether resins, and modified rosins, mixtures of these resins with the above-mentioned vinyl resins, or graft polymers obtained by polymerizing vinyl monomers in the coexistence of these resins.

[0091] Among them, styrene-acrylic acid copolymer or polyester resin is suitable, and polyester resin is more suitable.

[0092] These adhesive resins may be used alone or in combination of two or more.

[0093] Examples of the binder resin include non-crystalline (also referred to as “amorphous”) resins and crystalline resins.

[0094] From the viewpoint of suppressing density unevenness in the obtained image, the binder resin preferably contains a crystalline resin, and more preferably contains an amorphous resin and a crystalline resin.

[0095] The content of the crystalline resin is preferably 2 mass % to 40 mass %, and more preferably 2 mass % to 20 mass %, based on the total mass of the binder resin.

[0096] It should be noted that the "crystallinity" of a resin means that there is no step-like change in endothermic value in differential scanning calorimetry (DSC) and that there is a clear endothermic peak. Specifically, it means that the half-width of the endothermic peak when measured at a heating rate of 10 (°C / min) is within 10°C.

[0097] On the other hand, the "amorphous" nature of a resin means that the half-peak width is larger than 10°C, the endothermic quantity changes stepwise, or no clear endothermic peak is observed.

[0098] <<Polyester resin>>

[0099] Examples of the polyester resin include known polyester resins.

[0100] Amorphous polyester resin

[0101] Examples of the non-crystalline polyester resin include polycondensates of polycarboxylic acids and polyols. As the non-crystalline polyester resin, a commercially available product may be used, or a synthetic product may be used.

[0102] Examples of the polycarboxylic acid include aliphatic dicarboxylic acids (e.g., oxalic acid, malonic acid, maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, succinic acid, alkenyl succinic acid, adipic acid, sebacic acid, etc.), alicyclic dicarboxylic acids (e.g., cyclohexane dicarboxylic acid, etc.), aromatic dicarboxylic acids (e.g., terephthalic acid, isophthalic acid, phthalic acid, naphthalene dicarboxylic acid, etc.), and their anhydrides or their lower (e.g., carbon number 1 to 5) alkyl esters. Among these, aromatic dicarboxylic acids are preferred as the polycarboxylic acid.

[0103] Among the polycarboxylic acids, dicarboxylic acids and trivalent or higher carboxylic acids having a crosslinked structure or a branched structure may be used in combination. Examples of the trivalent or higher carboxylic acids include trimellitic acid, pyromellitic acid, their anhydrides, or their lower (e.g., carbon number 1 to 5) alkyl esters.

[0104] The polyvalent carboxylic acid may be used alone or in combination of two or more.

[0105] Examples of the polyol include aliphatic diols (e.g., ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, butanediol, hexanediol, neopentyl glycol, etc.), alicyclic diols (e.g., cyclohexanediol, cyclohexanedimethanol, hydrogenated bisphenol A, etc.), and aromatic diols (e.g., ethylene oxide adducts of bisphenol A, propylene oxide adducts of bisphenol A, etc.). Among these, the polyol is preferably an aromatic diol or an alicyclic diol, and more preferably an aromatic diol.

[0106] As the polyol, a diol may be used in combination with a trivalent or higher polyol having a cross-linked structure or a branched structure. Examples of the trivalent or higher polyol include glycerin, trimethylolpropane, and pentaerythritol.

[0107] The polyols may be used alone or in combination of two or more.

[0108] The glass transition temperature (Tg) of the amorphous polyester resin is preferably 50°C to 80°C, and more preferably 50°C to 65°C.

[0109] The glass transition temperature is determined from a DSC curve obtained by differential scanning calorimetry (DSC), more specifically, according to the "extrapolated glass transition start temperature" described in the glass transition temperature determination method of JIS K 7121-1987 "Determination of Transition Temperature of Plastics".

[0110] The weight average molecular weight (Mw) of the amorphous polyester resin is preferably 5,000 to 1,000,000, and more preferably 7,000 to 500,000.

[0111] The number average molecular weight (Mn) of the amorphous polyester resin is more preferably 2,000 to 100,000.

[0112] The molecular weight distribution Mw / Mn of the amorphous polyester resin is preferably 1.5 or more and 100 or less, and more preferably 2 or more and 60 or less.

[0113] It should be noted that the weight average molecular weight and the number average molecular weight are measured by gel permeation chromatography (GPC). In the molecular weight measurement using GPC, GPC HLC-8120GPC manufactured by Tosoh Corporation is used as a measuring device, and a column TSKgel SuperHM-M (15 cm) manufactured by Tosoh Corporation is used, and the measurement is performed using THF solvent. The weight average molecular weight and the number average molecular weight are calculated based on the measurement results using a molecular weight calibration curve made from a monodisperse polystyrene standard sample.

[0114] The amorphous polyester resin is obtained by a known production method. Specifically, for example, the amorphous polyester resin is obtained by setting the polymerization temperature to 180° C. to 230° C., reducing the pressure in the reaction system as necessary, and reacting while removing water or alcohol generated during condensation.

[0115] It should be noted that when the raw material monomer is insoluble or incompatible at the reaction temperature, a high boiling point solvent can be added as a dissolving aid to dissolve it. In this case, the polycondensation reaction is carried out while the dissolving aid is distilled off. In the case of a monomer with poor compatibility, the monomer with poor compatibility can be condensed in advance with an acid or alcohol to be polycondensed with the monomer, and then polycondensed with the main component.

[0116] Crystalline polyester resin

[0117] Examples of the crystalline polyester resin include polycondensates of polycarboxylic acids and polyols. As the crystalline polyester resin, a commercially available product may be used, or a synthetic product may be used.

[0118] Here, in order to make the crystalline polyester resin easily form a crystal structure, the crystalline polyester is preferably obtained by using a polycondensate obtained by using a polymerizable monomer having a linear aliphatic group rather than a polycondensate obtained by using a polymerizable monomer having an aromatic group.

[0119] Examples of the polycarboxylic acid include aliphatic dicarboxylic acids (e.g., oxalic acid, succinic acid, glutaric acid, adipic acid, suberic acid, azelaic acid, sebacic acid, 1,9-nonanedicarboxylic acid, 1,10-decanedicarboxylic acid, 1,12-dodecanedicarboxylic acid, 1,14-tetradecanedicarboxylic acid, 1,18-octadecanedicarboxylic acid, etc.), aromatic dicarboxylic acids (e.g., dibasic acids such as phthalic acid, isophthalic acid, terephthalic acid, and naphthalene-2,6-dicarboxylic acid, etc.), anhydrides thereof, or lower (e.g., carbon number 1 to 5) alkyl esters thereof.

[0120] Among the polycarboxylic acids, dicarboxylic acids and trivalent or higher carboxylic acids having a cross-linked structure or a branched structure may be used in combination. Examples of trivalent carboxylic acids include aromatic carboxylic acids (e.g., 1,2,3-benzenetricarboxylic acid, 1,2,4-benzenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, etc.), their anhydrides, or their lower (e.g., carbon number 1 to 5) alkyl esters.

[0121] As the polycarboxylic acid, these dicarboxylic acids may be used in combination with a dicarboxylic acid having a sulfonic acid group or a dicarboxylic acid having an ethylenic double bond.

[0122] The polyvalent carboxylic acid may be used alone or in combination of two or more.

[0123] Examples of the polyol include aliphatic diols (e.g., linear aliphatic diols having a main chain portion having carbon atoms of 7 or more and 20 or less). Examples of the aliphatic diols include ethylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, 1,12-dodecanediol, 1,13-tridecanediol, 1,14-tetradecanediol, 1,18-octadecanediol, and 1,14-eicosandiol. Among these, preferred aliphatic diols include 1,8-octanediol, 1,9-nonanediol, and 1,10-decanediol.

[0124] Among the polyols, diols may be used in combination with trivalent or higher alcohols having a cross-linked structure or a branched structure. Examples of the trivalent or higher alcohols include glycerin, trimethylolethane, trimethylolpropane, and pentaerythritol.

[0125] The polyols may be used alone or in combination of two or more.

[0126] Here, the content of the aliphatic diol in the polyol is preferably 80 mol % or more, and preferably 90 mol % or more.

[0127] The melting temperature of the crystalline polyester resin is preferably 50°C to 100°C, more preferably 55°C to 90°C, and even more preferably 60°C to 85°C.

[0128] The melting temperature is determined from a DSC curve obtained by differential scanning calorimetry (DSC) according to the “melting peak temperature” described in the method for measuring melting temperature in JIS K7121:1987 “Method for measuring transition temperatures of plastics”.

[0129] The weight average molecular weight (Mw) of the crystalline polyester resin is preferably 6,000 or more and 35,000 or less.

[0130] The crystalline polyester resin can be obtained, for example, by a known production method similar to the amorphous polyester.

[0131] From the aspect of the friction resistance of the image, the weight average molecular weight (Mw) of the adhesive resin is preferably 5,000 to 1,000,000, more preferably 7,000 to 500,000, and particularly preferably 25,000 to 60,000. The number average molecular weight (Mn) of the adhesive resin is preferably 2,000 to 100,000. The molecular weight distribution Mw / Mn of the adhesive resin is preferably 1.5 to 100, more preferably 2 to 60.

[0132] The weight average molecular weight and number average molecular weight of the binder resin are measured by gel permeation chromatography (GPC). In the molecular weight measurement using GPC, a GPC HLC-8120GPC manufactured by Tosoh Corporation is used as a measuring device, a column TSKgel SuperHM-M (15 cm) manufactured by Tosoh Corporation is used, and the measurement is performed using tetrahydrofuran (THF) solvent. The weight average molecular weight and number average molecular weight are calculated based on the measurement results using a molecular weight calibration curve prepared from a monodisperse polystyrene standard sample.

[0133] The content of the binder resin is preferably 40% to 95% by mass, more preferably 50% to 90% by mass, and even more preferably 60% to 85% by mass, based on the entire fluorescent resin particles or colored resin particles.

[0134] -Release agent-

[0135] Examples of the release agent include hydrocarbon waxes, natural waxes such as carnauba wax, rice wax, and candelilla wax, synthetic waxes such as montan wax, or mineral and petroleum waxes, and ester waxes such as fatty acid esters and montanic acid esters. The release agent is not limited thereto.

[0136] The melting temperature of the release agent is preferably 50°C to 110°C, more preferably 60°C to 100°C.

[0137] The melting temperature is determined from a DSC curve obtained by differential scanning calorimetry (DSC) according to the “melting peak temperature” described in the method for measuring melting temperature in JIS K7121:1987 “Method for measuring transition temperatures of plastics”.

[0138] The content of the release agent is preferably 1% by mass to 20% by mass, and more preferably 5% by mass to 15% by mass, based on the entirety of the fluorescent resin particles or the colored resin particles.

[0139] -Other additives-

[0140] Examples of other additives include known additives such as magnetic materials, charge control agents, and inorganic powders. These additives may be contained in the fluorescent resin particles or the colored resin particles as internal additives.

[0141] - Characteristics of fluorescent resin particles or colored resin particles, etc. -

[0142] The fluorescent resin particles or colored resin particles may be resin particles of a single-layer structure, or may be resin particles of a so-called core / shell structure (core / shell type particles) composed of a core (core particle) and a coating layer (shell layer) covering the core. The core / shell structured resin particles may be composed of, for example, a core containing a binding resin and, if necessary, a colorant and a release agent, and the coating layer containing a binding resin.

[0143] (External Additives)

[0144] When the fluorescent resin particles or the colored resin particles are used as a toner for electrostatic image development described later, the fluorescent resin particles or the colored resin particles may contain an external additive as necessary.

[0145] Furthermore, the fluorescent resin particles or colored resin particles used in the present embodiment may be resin particles without an external additive, or may be particles in which an external additive is added to the resin particles.

[0146] Examples of the external additive include inorganic particles. Examples of the inorganic particles include SiO2, TiO2, Al2O3, CuO, ZnO, SnO2, CeO2, Fe2O3, MgO, BaO, CaO, K2O, Na2O, ZrO2, CaO·SiO2, K2O·(TiO2) n , Al2O3·2SiO2, CaCO3, MgCO3, BaSO4, MgSO4, etc.

[0147] The surface of the inorganic particles as an external additive can also be subjected to a hydrophobic treatment. The hydrophobic treatment is carried out by, for example, immersing the inorganic particles in a hydrophobic treatment agent. The hydrophobic treatment agent is not particularly limited, and for example, a silane coupling agent, silicone oil, a titanate coupling agent, an aluminum coupling agent, etc. can be cited. These treatment agents can be used alone or in combination of two or more.

[0148] The amount of the hydrophobizing agent is, for example, preferably 1 part by mass or more and 10 parts by mass or less relative to 100 parts by mass of the inorganic particles.

[0149] Examples of the external additives include resin particles (polystyrene, polymethyl methacrylate (PMMA), melamine resin and other resin particles), detergent active agents (metal salts of higher fatty acids such as zinc stearate, and particles of fluorine-based high molecular weight bodies).

[0150] The amount of the external additive added is, for example, preferably 0.01% by mass to 10% by mass, and more preferably 0.01% by mass to 6% by mass, based on the fluorescent resin particles or the colored resin particles.

[0151] <Application of resin pellet combination>

[0152] The resin particle combination of this embodiment is suitable for use as a resin particle combination for image formation, and is more suitable for use as a toner combination for electrostatic image development. In this case, it is preferred that the combination comprises a fluorescent color toner containing a fluorescent colorant and a colored toner containing a colored colorant, the volume average particle size of the fluorescent color toner being larger than the volume average particle size of the colored toner, and the average circularity of the fluorescent color toner being 0.93 or more.

[0153] In addition, the resin particle combination of this embodiment is also suitable for use as a powder coating combination. It can also be used to apply it to the surface to be coated, and then heat (baking) it to form a coating film to solidify the powder, so as to manufacture a coated product. In this case, coating and heating (baking) can be performed simultaneously.

[0154] The powder can be applied by a known coating method such as spray coating, electrostatic powder coating, friction charging powder coating, fluidization dipping, etc. The thickness of the powder coating film is preferably 30 μm or more and 50 μm or less, for example.

[0155] The heating temperature (calcining temperature) is, for example, preferably 90° C. to 250° C., more preferably 100° C. to 220° C., and further preferably 120° C. to 200° C. The heating time (calcining time) is adjusted by the heating temperature (calcining temperature).

[0156] The object to which the powder is applied is not particularly limited, and examples thereof include various metal parts, ceramic parts, resin parts, etc. These object objects may be unformed products before being formed into various articles such as plate-shaped products and linear products, or may be formed products for electronic parts, road vehicles, and interior and exterior decorative materials for buildings. In addition, the object objects may be articles on which the surface to be coated has been previously subjected to a surface treatment such as primer treatment, plating treatment, or electrodeposition coating.

[0157] Furthermore, the resin particle combination of the present embodiment can also be suitably used as a resin particle combination for a toner display in fields other than coating.

[0158] Toner displays are well known in which charged resin particles are dispersed in a medium (mostly air) and the resin particles are moved under the action of an electric field to display an image. The resin particles of this embodiment can also be used in this method without any problem. For example, resin particles are placed in a cell sandwiched between two transparent electrodes, and a voltage is applied to move the resin particles to display an image.

[0159] [Method for producing fluorescent resin particles or colored resin particles]

[0160] Next, a method for producing the fluorescent resin particles or the colored resin particles will be described.

[0161] The fluorescent resin particles or colored resin particles used in the present embodiment may be prepared by adding an external additive to the resin particles as needed.

[0162] The fluorescent resin particles or colored resin particles can be produced by any of dry methods (e.g., kneading and pulverization methods, etc.) and wet methods (e.g., aggregation and merging (aggregation and unification) methods, suspension polymerization methods, and dissolution and suspension methods, etc.). These methods are not particularly limited, and known methods are used. Among these, it is preferable to obtain the fluorescent resin particles or colored resin particles by the aggregation and merging method.

[0163] Examples of the agglomeration method include the method described in Japanese Patent Application Laid-Open No. 2010-97101 and Japanese Patent Application Laid-Open No. 2006-154641.

[0164] Examples of the kneading and pulverizing method include the method described in Japanese Patent Application Laid-Open No. 2000-267338.

[0165] As the dissolution suspension method, there can be mentioned the method described in Japanese Patent Application Laid-Open No. 2000-258950.

[0166] In addition, specifically, for example, in the case of manufacturing fluorescent resin particles or colored resin particles by an agglomeration and merging method, the fluorescent resin particles or colored resin particles are manufactured through the following steps: a step of preparing a resin particle dispersion in which resin particles serving as a binding resin are dispersed (resin particle dispersion preparation step); a step of agglomerating resin particles (and other particles if necessary) in the resin particle dispersion (in a dispersion after mixing other particle dispersions if necessary) to form agglomerated particles (agglomerated particle formation step); and a step of heating the agglomerated particle dispersion in which the agglomerated particles are dispersed to fuse / merge (fusion / unity) the agglomerated particles to form fluorescent resin particles or colored resin particles (fusion / merging step).

[0167] The details of each step are described below.

[0168] In the following description, a method for obtaining resin particles containing a colorant and a release agent is described, but the colorant and the release agent are components used as needed. Of course, other additives besides the colorant and the release agent may also be used.

[0169] In the following description, the colorant may be at least one colorant selected from the group consisting of the fluorescent colorant and the colored colorant. In addition, the colorant particle dispersion may be a fluorescent colorant particle dispersion, a colored colorant particle dispersion, a dispersion containing fluorescent colorant particles and colored colorant particles, or the like.

[0170] - Resin particle dispersion preparation step -

[0171] A resin particle dispersion in which resin particles as a binder resin are dispersed is prepared, and at the same time, for example, a colorant particle dispersion in which colorant particles are dispersed and a release agent particle dispersion in which release agent particles are dispersed are prepared.

[0172] The resin particle dispersion is prepared, for example, by dispersing the resin particles in a dispersion medium using a surfactant.

[0173] Examples of the dispersion medium used for the resin particle dispersion include aqueous media.

[0174] Examples of the aqueous medium include water such as distilled water and ion-exchanged water, alcohols, etc. These media may be used alone or in combination of two or more.

[0175] Examples of surfactants include anionic surfactants such as sulfate ester salts, sulfonates, phosphates, and soaps; cationic surfactants such as amine salts and quaternary ammonium salts; and nonionic surfactants such as polyethylene glycols, alkylphenol ethylene oxide adducts, and polyols. Among these, anionic surfactants and cationic surfactants are particularly useful. Nonionic surfactants may also be used in combination with anionic surfactants or cationic surfactants.

[0176] Among them, a nonionic surfactant is preferably used, and a nonionic surfactant is preferably used in combination with an anionic surfactant or a cationic surfactant.

[0177] The surfactant may be used alone or in combination of two or more.

[0178] In the resin particle dispersion, as a method for dispersing the resin particles in the dispersion medium, for example, a common dispersion method using a rotary shearing homogenizer or a ball mill, sand mill, bead mill, etc. with a medium can be cited. In addition, depending on the type of resin particles, the resin particles can also be dispersed in the dispersion medium using a phase inversion emulsification method. The phase inversion emulsification method is a method in which the resin to be dispersed is dissolved in a hydrophobic organic solvent that can dissolve the resin, a base is added to the organic continuous phase (O phase) for neutralization, and then an aqueous medium (W phase) is added to thereby invert the phase from W / O to O / W, so that the resin is dispersed in the aqueous medium in a particle form.

[0179] The volume average particle size of the resin particles dispersed in the resin particle dispersion is, for example, preferably 0.01 μm or more and 1 μm or less, more preferably 0.08 μm or more and 0.8 μm or less, and further preferably 0.1 μm or more and 0.6 μm or less.

[0180] The volume average particle size of the resin particles is determined by using a particle size distribution obtained by measurement using a laser diffraction particle size distribution measuring device (e.g., LA-700 manufactured by Horiba, Ltd.). For the divided particle size range (segment), a cumulative distribution is plotted for volume from the small particle size side, and the particle size at the cumulative 50% point relative to all particles is measured, which is taken as the volume average particle size D50v. The volume average particle size of particles in other dispersions is measured in the same manner.

[0181] The content of the resin particles contained in the resin particle dispersion is preferably 5% by mass or more and 50% by mass or less, and more preferably 10% by mass or more and 40% by mass or less.

[0182] For example, a colorant particle dispersion and a release agent particle dispersion are prepared in the same manner as the resin particle dispersion. That is, the volume average particle size of the particles in the resin particle dispersion, the dispersion medium, the dispersion method, and the content of the particles are the same for the colorant particles dispersed in the colorant particle dispersion and the release agent particles dispersed in the release agent particle dispersion.

[0183] - Agglomerated Particle Formation Step-

[0184] Next, the resin particle dispersion, the colorant particle dispersion, and the release agent particle dispersion are mixed.

[0185] Then, the resin particles, colorant particles and release agent particles are heterogeneously aggregated in the mixed dispersion to form aggregated particles containing the resin particles, colorant particles and release agent particles and having a diameter close to that of the target fluorescent resin particles or colored resin particles.

[0186] Specifically, for example, a coagulant is added to the mixed dispersion, and the pH of the mixed dispersion is adjusted to acidity (for example, pH 2 to 5), a dispersion stabilizer is added as needed, and then heated to a temperature close to the glass transition temperature of the resin particles (specifically, for example, the glass transition temperature of the resin particles is -30°C to the glass transition temperature of -10°C), so that the particles dispersed in the mixed dispersion are agglomerated to form agglomerated particles.

[0187] In the aggregated particle forming step, for example, a coagulant may be added at room temperature (e.g., 25° C.) while the mixed dispersion is stirred using a rotary shearing homogenizer, the pH of the mixed dispersion is adjusted to acidic (e.g., pH 2 to 5), a dispersion stabilizer may be added as needed, and then the mixture may be heated.

[0188] Examples of the coagulant include surfactants having opposite polarity to the surfactant contained in the mixed dispersion, inorganic metal salts, and divalent or higher metal complexes. When a metal complex is used as the coagulant, the amount of surfactant used is reduced and the charging characteristics are improved.

[0189] If necessary, an additive that forms a complex or similar bond with the metal ion of the coagulant may be used together with the coagulant. As the additive, a chelating agent is preferably used.

[0190] Examples of the inorganic metal salt include metal salts such as calcium chloride, calcium nitrate, barium chloride, magnesium chloride, zinc chloride, aluminum chloride, and aluminum sulfate; inorganic metal salt polymers such as polyaluminum chloride, polyaluminum hydroxide, and calcium polysulfide; and the like.

[0191] As the chelating agent, a water-soluble chelating agent can be used. Examples of the chelating agent include hydroxycarboxylic acids such as tartaric acid, citric acid, and gluconic acid; aminocarboxylic acids such as iminodiacetic acid (IDA), nitrilotriacetic acid (NTA), and ethylenediaminetetraacetic acid (EDTA); and the like.

[0192] The amount of the coagulant added is preferably 0.01 parts by mass or more and 5.0 parts by mass or less, and more preferably 0.1 parts by mass or more and less than 3.0 parts by mass, relative to 100 parts by mass of the resin particles.

[0193] - Fusion / Merge (Fusion·Unification) Steps-

[0194] Next, the agglomerated particle dispersion containing the agglomerated particles is heated to, for example, a temperature above the glass transition temperature of the resin particles (for example, a temperature 30°C to 50°C higher than the glass transition temperature of the resin particles) and to a temperature above the melting point of the release agent to allow the agglomerated particles to fuse / merge to form fluorescent resin particles or colored resin particles.

[0195] In the fusion / merging step, the resin and the release agent are in a fused state above the glass transition temperature of the resin particles and above the melting temperature of the release agent. Thereafter, the particles are cooled to obtain fluorescent resin particles or colored resin particles.

[0196] As a method for adjusting the aspect ratio of the release agent in the fluorescent resin particles or the colored resin particles, the aspect ratio can be adjusted by maintaining the temperature around the solidification point of the release agent for a certain period of time during cooling to allow crystal growth, or by using two or more release agents with different melting points to promote crystal growth during cooling.

[0197] Fluorescent resin particles or colored resin particles are obtained through the above steps.

[0198] After obtaining a dispersion of agglomerated particles in which agglomerated particles are dispersed, fluorescent resin particles or colored resin particles can be manufactured through the following steps: further mixing the above-mentioned dispersion of agglomerated particles with a resin particle dispersion in which resin particles are dispersed, and agglomerating the resin particles in a manner that further adheres to the surface of the agglomerated particles to form second agglomerated particles; and heating the second agglomerated particle dispersion in which the second agglomerated particles are dispersed to fuse / merge the second agglomerated particles to form fluorescent resin particles or colored resin particles with a core / shell structure.

[0199] After the fusion / merging step is completed, the fluorescent resin particles or colored resin particles formed in the solution are subjected to a known washing step, a solid-liquid separation step, and a drying step to obtain fluorescent resin particles or colored resin particles in a dry state. Regarding the washing step, from the perspective of charging performance, replacement washing using ion exchange water can be fully implemented. Regarding the solid-liquid separation step, from the perspective of productivity, suction filtration, pressure filtration, etc. can be implemented. Regarding the drying step, from the perspective of productivity, freeze drying, airflow drying, fluidized bed drying, vibration fluidized bed drying, etc. can be implemented.

[0200] Then, for example, an external additive is added to the obtained dry fluorescent resin particles or colored resin particles as needed and mixed, thereby producing fluorescent resin particles or colored resin particles. Mixing can be performed using, for example, a V-type blender, a Henschel mixer, a Loedige mixer, etc. Furthermore, coarse particles of the fluorescent resin particles or colored resin particles can be removed using a vibration sieving machine, a wind sieving machine, etc. as needed.

[0201] <Electrostatic Image Developer Combination>

[0202] When the resin particle set of this embodiment is used as an electrostatic image developer set, it may be a single-component developer containing only fluorescent resin particles or colored resin particles, or a two-component developer in which the fluorescent resin particles or colored resin particles are mixed with a carrier.

[0203] The carrier is not particularly limited, and any known carrier may be used. Examples of the carrier include: a coated carrier in which a coating resin is coated on the surface of a core material formed of magnetic powder; a magnetic powder dispersion carrier in which magnetic powder is dispersed and mixed in a matrix resin; a resin impregnated carrier in which a porous magnetic powder is impregnated with a resin; and the like.

[0204] Note that the magnetic powder dispersed carrier and the resin impregnated carrier may be carriers in which the constituent particles of the carrier are used as core materials and the core materials are coated with a coating resin.

[0205] Examples of the magnetic powder include magnetic metals such as iron, nickel, and cobalt; and magnetic oxides such as ferrite and magnetite.

[0206] Examples of the coating resin and base resin include polyethylene, polypropylene, polystyrene, polyvinyl acetate, polyvinyl alcohol, polyvinyl butyral, polyvinyl chloride, polyvinyl ether, polyvinyl ketone, vinyl chloride-vinyl acetate copolymer, styrene-acrylate copolymer, pure silicone resin containing an organic siloxane bond or a modified product thereof, fluororesin, polyester, polycarbonate, phenol resin, epoxy resin, and the like.

[0207] It should be noted that the coating resin and the base resin may contain conductive particles and other additives.

[0208] Examples of the conductive particles include particles of metals such as gold, silver, and copper, carbon black, titanium oxide, zinc oxide, tin oxide, barium sulfate, aluminum borate, and potassium titanate.

[0209] Here, when the coating resin is coated on the surface of the core material, a coating layer forming solution obtained by dissolving the coating resin and various additives as necessary in a suitable solvent can be enumerated to coat the surface of the core material, etc. The solvent is not particularly limited and can be selected by considering the coating resin used, coating suitability, etc.

[0210] Specific resin coating methods include: an immersion method, in which the core material is immersed in a coating layer forming solution; a spray method, in which the coating layer forming solution is sprayed onto the surface of the core material; a fluidized bed method, in which the coating layer forming solution is sprayed while the core material is suspended by flowing air; a kneading coater method, in which the core material of the carrier is mixed with the coating layer forming solution in a kneading coater and then the solvent is removed; and the like.

[0211] The mixing ratio (mass ratio) of the resin particles (toner for electrostatic image development) and the carrier in the two-component developer is preferably resin particles (toner for electrostatic image development):carrier=1:100 to 30:100, more preferably 3:100 to 20:100.

[0212] <Image Forming Apparatus / Image Forming Method>

[0213] An image forming apparatus and an image forming method in the case where the resin particle combination of the present embodiment is used as a toner combination for electrostatic image development will be described.

[0214] The image forming device comprises: a first image forming mechanism, which forms a fluorescent color image using the above-mentioned fluorescent color toner in the toner combination; a second image forming mechanism, which forms a colored image using the above-mentioned colored toner in the toner combination; a transfer mechanism, which transfers the above-mentioned fluorescent color image and the above-mentioned colored image onto a recording medium; and a fixing mechanism, which fixes the above-mentioned fluorescent color image and the above-mentioned colored image onto the recording medium.

[0215] In addition, the image forming device may also be in the form of a first image forming mechanism and a second image forming mechanism, each of which has the following components: an image retaining body; a charging mechanism for charging the surface of the image retaining body; an electrostatic image forming mechanism for forming an electrostatic image on the charged surface of the image retaining body; and a developing mechanism for developing the electrostatic image formed on the surface of the image retaining body into a toner image using an electrostatic image developer.

[0216] In addition, the form of the image holder may include the following components: an image holder; a charging mechanism for charging the surface of the image holder; an electrostatic image forming mechanism for forming an electrostatic image on the charged surface of the image holder; and first and second developing mechanisms as the first and second image forming mechanisms for developing the electrostatic image formed on the surface of the image holder into a toner image using an electrostatic image developer.

[0217] In such an image forming device, an image forming method having the following steps is implemented: a first image forming step of forming a fluorescent color image using a fluorescent color toner in a toner combination; a second image forming step of forming a colored image using the above-mentioned colored toner in the toner combination; a transfer step of transferring the above-mentioned fluorescent color image and the above-mentioned colored image onto a recording medium; and a fixing step of fixing the above-mentioned fluorescent color image and the above-mentioned colored image onto a recording medium.

[0218] The following well-known image forming devices can be applied: a device using a direct transfer method for directly transferring a toner image (a fluorescent image or a colored image in the present embodiment) formed on the surface of an image retaining body to a recording medium; a device using an intermediate transfer method for transferring a toner image formed on the surface of an image retaining body once to the surface of an intermediate transfer body, and for a second time transferring the toner image transferred to the surface of the intermediate transfer body to the surface of a recording medium; a device having a cleaning mechanism for cleaning the surface of an image retaining body after the transfer of the toner image and before charging; a device having a de-staticizing mechanism for de-staticizing the surface of an image retaining body by irradiating de-staticizing light to the surface of the image retaining body after the transfer of the toner image and before charging; and the like.

[0219] In the case of an intermediate transfer device, the transfer mechanism used is, for example, a structure having the following components: an intermediate transfer body that transfers a toner image to a surface; a primary transfer mechanism that transfers a toner image formed on the surface of an image retaining body to the surface of the intermediate transfer body for the first time; and a secondary transfer mechanism that transfers the toner image transferred to the surface of the intermediate transfer body to the surface of a recording medium for the second time.

[0220] An example of an image forming apparatus will be described below. In the following description, the main parts shown in the drawings will be described, and the description of other parts will be omitted.

[0221] Figure 1 This is a schematic diagram showing the structure of the image forming apparatus used in the present embodiment, and is a diagram showing an image forming apparatus of a five-drum tandem system and an intermediate transfer system.

[0222] Figure 1 The image forming apparatus shown in the figure is provided with the first to fifth image forming units 150Y, 150M, 150C, 150K, 150B (image forming mechanism) of the electrophotographic method for outputting images of yellow (Y), magenta (M), cyan (C), black (K), and fluorescent color (B) based on color separation image data. These image forming units (hereinafter sometimes referred to as "units") 150Y, 150M, 150C, 150K, 150B are arranged in parallel with each other at a predetermined distance in the horizontal direction. These units 150Y, 150M, 150C, 150K, 150B may be process cartridges that are detachable from the image forming apparatus.

[0223] The intermediate transfer belt (an example of an intermediate transfer body) 133 extends through each unit and is arranged below each unit 150Y, 150M, 150C, 150K, and 150B. The intermediate transfer belt 133 is wound around a driving roller 113, a supporting roller 112, and an opposing roller 114 that are in contact with the inner surface of the intermediate transfer belt 133 so that it extends in a direction from the first unit 150Y to the fifth unit 150B ( Figure 1The intermediate transfer belt 133 is operated in the direction of arrow B in FIG. 11. An intermediate transfer body cleaning device 116 is provided on the image holding surface side of the intermediate transfer belt 133 so as to face the driving roller 113. In addition, a voltage applying device 160 is provided on the upstream side of the intermediate transfer belt 133 in the rotation direction relative to the intermediate transfer body cleaning device 116, and an electric field is generated between the intermediate transfer belt 133 by generating a potential difference between the supporting rollers 113.

[0224] In the developing devices (an example of developing mechanisms) 120Y, 120M, 120C, 120K, 120B of each unit 150Y, 150M, 150C, 150K, 150B, yellow, magenta, cyan, black, and fluorescent color toners stored in toner boxes 140Y, 140M, 140C, 140K, 140B are supplied respectively.

[0225] The first to fifth units 150Y, 150M, 150C, 150K, and 150B have the same configuration, operation, and function, and therefore, the first unit 150Y for forming a yellow image, which is disposed on the upstream side in the running direction of the intermediate transfer belt, will be described as a representative.

[0226] The first unit 150Y has a photosensitive body 111Y that functions as an image holder. The following are arranged in order around the photosensitive body 111Y: a charging roller (an example of a charging mechanism) 118Y that charges the surface of the photosensitive body 111Y to a preset potential; an exposure device (an example of an electrostatic image forming mechanism) 119Y that forms an electrostatic image by exposing the charged surface to laser light based on a color separation image signal; a developing device (an example of a developing mechanism) 120Y that supplies toner to the electrostatic image to develop the electrostatic image; a primary transfer roller (an example of a primary transfer mechanism) 117Y that transfers the developed toner image to the intermediate transfer belt 133; and a photosensitive body cleaning device (an example of a cleaning unit) 115Y that removes the toner remaining on the surface of the photosensitive body 111Y after the primary transfer.

[0227] The primary transfer roller 117Y is arranged inside the intermediate transfer belt 133 and is set at a position opposite to the photosensitive body 111Y. The primary transfer rollers 117Y, 117M, 117C, 117K, and 117B of each unit are connected to bias power supplies (not shown) for applying primary transfer bias. Each bias power supply changes the value of the transfer bias applied to each primary transfer roller by control by a control unit (not shown).

[0228] Next, the operation of forming a yellow image in the first unit 150Y will be described.

[0229] First, before the operation, the surface of the photoreceptor 111Y is charged to a potential of -600 V to -800 V by the charging roller 118Y.

[0230] The photoreceptor 111Y has a conductivity (e.g., a volume resistivity of 1×10 -6 The photosensitive layer is formed by laminating a photosensitive layer on a substrate with a resistance of 100 Ωcm or less. The photosensitive layer generally has a high resistance (resistance of a common resin), but has a property that the resistivity of the portion irradiated with the laser beam changes when the laser beam is irradiated. Therefore, according to the yellow image data sent from the control unit (not shown), the laser beam is irradiated from the exposure device 119Y to the surface of the charged photoreceptor 111Y. As a result, an electrostatic image of a yellow image pattern is formed on the surface of the photoreceptor 111Y.

[0231] The electrostatic image is an image formed on the surface of the photosensitive body 111Y by charging, which is a so-called negative latent image. The negative latent image is formed as follows: the resistivity of the irradiated portion of the photosensitive layer is reduced by using the laser beam from the exposure device 119Y, so that the charged charge on the surface of the photosensitive body 111Y flows; on the other hand, the charge of the portion not irradiated with the laser beam remains, thereby forming the negative latent image.

[0232] The electrostatic image formed on the photoconductor 111Y rotates to a preset development position as the photoconductor 111Y runs. At the development position, the electrostatic image on the photoconductor 111Y is developed into a toner image by the developing device 120Y and visualized.

[0233] An electrostatic image developer, for example, containing at least a yellow toner and a carrier, is stored in the developing device 120Y. The yellow toner is frictionally charged by being stirred inside the developing device 120Y, and has a charge of the same polarity (negative polarity) as the charge charged on the photoreceptor 111Y, and is retained on the developer roller (an example of a developer retainer). Afterwards, the surface of the photoreceptor 111Y passes through the developing device 120Y, whereby the yellow toner is electrostatically attached to the latent image portion on the surface of the photoreceptor 111Y that has been de-charged, and the latent image is developed using the yellow toner. The photoreceptor 111Y on which the yellow toner image is formed continues to run at a preset speed, and the toner image developed on the photoreceptor 111Y is conveyed to a preset primary transfer position.

[0234] When the yellow toner image on the photoreceptor 111Y is transported to the primary transfer position, a primary transfer bias is applied to the primary transfer roller 117Y, and the electrostatic force from the photoreceptor 111Y toward the primary transfer roller 117Y acts on the toner image, so that the toner image on the photoreceptor 111Y is transferred to the intermediate transfer belt 133. The transfer bias applied at this time has a polarity (+) opposite to the polarity (-) of the toner, and is controlled to, for example, +10 μA by a control unit (not shown) in the first unit 150Y.

[0235] On the other hand, the toner remaining on the photoconductor 111Y is removed and recovered by the photoconductor cleaning device 115Y.

[0236] The primary transfer bias applied to the primary transfer rollers 117M, 117C, 117K, and 117B after the second unit 150M is also controlled in accordance with the first unit.

[0237] In this way, the intermediate transfer belt 133 to which the yellow toner image has been transferred by the first unit 150Y is sequentially conveyed through the second to fifth units 150M, 150C, 150K, and 150B, so that the toner images of the respective colors are multi-transferred in a superimposed manner.

[0238] The intermediate transfer belt 133 to which the five-color toner image has been multi-transferred by the first to fifth units arrives at the secondary transfer section, which is composed of the intermediate transfer belt 133, the opposing roller 114 in contact with the inner surface of the intermediate transfer belt, and the secondary transfer roller (an example of a secondary transfer mechanism) 134 arranged on the image holding surface side of the intermediate transfer belt 133. On the other hand, the recording paper (an example of a recording medium) P is sent to the gap between the secondary transfer roller 134 and the intermediate transfer belt 133 by the feeding member at a preset timing, and a secondary transfer bias is applied to the opposing roller 114. The transfer bias applied at this time has the same (-) polarity as the polarity (-) of the toner, and the electrostatic force from the intermediate transfer belt 133 toward the recording paper P acts on the toner image, so that the toner image on the intermediate transfer belt 133 is transferred to the recording paper P. The secondary transfer bias at this time is determined based on the resistance detected by a resistance detection mechanism (not shown) that detects the resistance of the secondary transfer portion, and the voltage is controlled.

[0239] Thereafter, the recording paper P is fed into a pressure-contact portion (nip portion) of a pair of fixing rollers in a fixing device (an example of a fixing mechanism) 135 , and the toner image is fixed on the recording paper P to form a fixed image.

[0240] Examples of the recording paper P to which the toner image is transferred include plain paper used in electrophotographic copy machines, printers, and the like. Examples of the recording medium include, in addition to the recording paper P, OHP transparent films and the like.

[0241] In order to further improve the smoothness of the image surface after fixing, the surface of the recording paper P is preferably smooth. For example, coated paper obtained by coating the surface of ordinary paper with a resin or the like, art paper for printing, etc. are preferably used.

[0242] The recording paper P on which the color image has been fixed is sent to the discharge portion, and a series of color image forming operations are completed.

[0243] It should be noted that Figure 1The image forming apparatus shown is an image forming apparatus having a structure of attaching and detaching toner cartridges 140Y, 140M, 140C, 140K, and 140B, and the developing devices 120Y, 120M, 120C, 120K, and 120B are connected to the toner cartridges corresponding to the respective developing devices (colors) by toner supply pipes not shown. In addition, when the toner stored in the toner cartridge is insufficient, the toner cartridge is replaced.

[0244] <Process Cartridge / Toner Cartridge Combination>

[0245] A process cartridge in the case of using the resin particle combination of the present embodiment as a toner combination for electrostatic image development will be described.

[0246] The process cartridge is a process cartridge that is loaded and unloaded in an image forming apparatus and includes: a first developing mechanism that stores a first electrostatic image developer in an electrostatic image developer set; and a second developing mechanism that stores the second electrostatic image developer in the electrostatic image developer set of this embodiment.

[0247] It should be noted that the process cartridge is not limited to the above-mentioned structure, and may be provided with a developing device and, if necessary, at least one of other mechanisms selected from an image holding member, a charging mechanism, an electrostatic image forming mechanism, and a transfer mechanism.

[0248] An example of the process cartridge is shown below, but the present invention is not limited thereto. It should be noted that the main parts shown in the drawings will be described, and the description of other parts will be omitted.

[0249] Figure 2 1 is a diagram schematically showing the structure of a process cartridge used in this embodiment.

[0250] Figure 2 The processing box 200 shown is constructed by, for example, combining and retaining a photosensitive body 207 (an example of an image holding body) and a charging roller 208 (an example of a charging mechanism) provided around the photosensitive body 207, a developing device 211 (an example of a developing mechanism), and a photosensitive body cleaning device 213 (an example of a cleaning unit) in an integral manner through a shell 217 having a mounting guide 216 and an opening 218 for exposure to form an ink cartridge.

[0251] It should be noted that Figure 2In the figure, 209 indicates an exposure device (an example of an electrostatic image forming mechanism), 212 indicates a primary transfer roller (an example of a primary transfer mechanism), 220 indicates an intermediate transfer belt (an example of an intermediate transfer body), 222 indicates a driving roller which also serves as an intermediate transfer belt de-staticizing mechanism (an example of an intermediate transfer body de-staticizing mechanism), 224 indicates a supporting roller, 226 indicates a secondary transfer roller (an example of a secondary transfer mechanism), 228 indicates a fixing device (an example of a fixing mechanism), and 300 indicates recording paper (an example of a recording medium).

[0252] Next, a toner cartridge set in the case where the resin particle set of the present embodiment is used as a toner set for electrostatic image development will be described.

[0253] The toner cartridge set is a toner cartridge set that is attached to and detached from the image forming apparatus, and includes: a first toner cartridge storing the fluorescent color toner in the toner set; and a second toner cartridge storing the color toner in the toner set.

[0254] Each toner cartridge stores replenishment toner to be supplied to each developing mechanism provided in the image forming apparatus.

[0255] [Example]

[0256] The following is an explanation of examples of the present invention, but the present invention is not limited to the following examples. It should be noted that in the following description, "parts" and "%" are all based on mass unless otherwise specified.

[0257] (Example 1)

[0258] <Preparation of Fluorescent Colorant Particle Dispersion (1)>

[0259] Fluorescent colorant (basic violet 11:1): 70 parts

[0260] Anionic surfactant (Neogen RK, manufactured by Daiichi Kogyo Chemical Co., Ltd.): 30 parts

[0261] Ion exchange water: 200 parts

[0262] The above materials were mixed and dispersed for 10 minutes using a homogenizer (ULTRA-TURRAX T50 manufactured by IKA Co.), and ion exchanged water was added so that the solid content in the dispersion became 20% by mass to obtain a fluorescent colorant particle dispersion (1) in which colorant particles having a volume average particle size of 140 nm were dispersed.

[0263] <Preparation of Fluorescent Colorant Particle Dispersion (2)>

[0264] A fluorescent colorant particle dispersion (2) was obtained in the same manner as in the preparation of the fluorescent colorant particle dispersion (1), except that 70 parts of the fluorescent colorant (basic violet 11:1) was replaced with 70 parts of the fluorescent colorant (basic red 1:1).

[0265] <Preparation of Colored Colorant Particle Dispersion (1)>

[0266] Colored colorant (CI Pigment Red 122): 70 parts

[0267] Anionic surfactant (Neogen RK, manufactured by Daiichi Kogyo Chemical Co., Ltd.): 30 parts

[0268] Ion exchange water: 200 parts

[0269] The above materials were mixed and dispersed for 10 minutes using a homogenizer (ULTRA-TURRAX T50 manufactured by IKA Co.), and ion exchange water was added so that the solid content in the dispersion became 20% by mass to obtain a colorant particle dispersion (1) in which colorant particles having a volume average particle size of 140 nm were dispersed.

[0270] <Preparation of Resin Particle Dispersion (1)>

[0271] Terephthalic acid: 30 mol parts

[0272] Fumaric acid: 70 mol parts

[0273] Bisphenol A ethylene oxide adduct: 5 mol parts

[0274] Bisphenol A propylene oxide adduct: 95 mol parts

[0275] The above materials were added to a flask equipped with a stirring device, a nitrogen inlet pipe, a temperature sensor and a distillation tower, and the temperature was raised to 220°C over 1 hour. 1 part of tetraethoxytitanium was added to 100 parts of the above materials. The temperature was raised to 230°C over 30 minutes while distilling off the generated water. After the dehydration condensation reaction was continued at this temperature for 1 hour, the reactant was cooled. In this way, a polyester resin with a weight average molecular weight of 18,000 and a glass transition temperature of 60°C was obtained.

[0276] 40 parts of ethyl acetate and 25 parts of 2-butanol were added to a container equipped with a temperature control mechanism and a nitrogen replacement mechanism to prepare a mixed solvent, and then 100 parts of a polyester resin was slowly added to dissolve it, and a 10% by mass ammonia aqueous solution (equivalent to 3 times the amount of the acid value of the resin in terms of molar ratio) was added thereto, and stirred for 30 minutes. Then, the container was replaced with dry nitrogen, and the temperature was maintained at 40°C. While stirring the mixed solution, 400 parts of ion exchange water was added dropwise at a rate of 2 parts / minute. After the addition was completed, the temperature was returned to room temperature (20°C to 25°C), and dry nitrogen was bubbled for 48 hours while stirring, thereby obtaining a resin particle dispersion in which ethyl acetate and 2-butanol were reduced to less than 1,000 ppm. Ion exchange water was added to the above resin particle dispersion to adjust the solid content to 20% by mass, thereby obtaining a resin particle dispersion (1).

[0277] <Preparation of Release Agent Particle Dispersion (1)>

[0278] Solid paraffin wax (HNP-9 manufactured by Nippon Seiro Co., Ltd.): 100 parts

[0279] Anionic surfactant (Neogen RK, manufactured by Daiichi Kogyo Chemical Co., Ltd.): 1 part

[0280] Ion exchange water: 350 parts

[0281] The above materials were mixed, heated to 100°C, dispersed using a homogenizer (IKA, trade name ULTRA-TURRAX T50), and then dispersed using a Manton Gaulin high-pressure homogenizer (Gaulin) to obtain a release agent particle dispersion (1) (solid content 20% by mass) in which release agent particles with a volume average particle size of 200 nm were dispersed.

[0282] <Production of Fluorescent Toner Particles (1)>

[0283] Resin particle dispersion (1): 60.05 parts

[0284] Fluorescent colorant particle dispersion (1): 1.00 part

[0285] Colored colorant particle dispersion (1): 0.20 parts

[0286] Release agent particle dispersion (1): 10.00 parts

[0287] Anionic surfactant (Daiichi Kogyo Chemical Co., Ltd.: NEOGEN RK, 20%): 0.75 parts

[0288] The above materials were placed in a round stainless steel flask, 0.1N (= mol / L) nitric acid was added to adjust the pH to 3.5, and then 30 parts of a nitric acid aqueous solution with a polyaluminium chloride concentration of 10% by mass was added. Then, the mixture was dispersed at a liquid temperature of 30°C using a homogenizer (manufactured by IKA, trade name ULTRA-TURRAX T50), and then heated to 45°C in a heating oil bath and maintained for 30 minutes. Thereafter, 28.00 parts of a resin particle dispersion (1) was added and maintained for 1 hour, and a 0.1N sodium hydroxide aqueous solution was added to adjust the pH to 8.5, and then heated to 84°C and maintained for 2.5 hours. Then, the mixture was cooled to 20°C at a rate of 20°C / min, the solid content was filtered out, and the mixture was fully washed with ion exchange water and dried to obtain fluorescent color toner particles (1).

[0289] The volume average particle size of the fluorescent toner particles (1) is 5.80 μm.

[0290] <Preparation of Carrier 1>

[0291] Ferrite particles (average particle size 35 μm): 100 parts

[0292] Toluene: 14 parts

[0293] Polymethyl methacrylate (MMA, weight average molecular weight 75,000): 5 parts

[0294] Carbon black: 0.2 parts (VXC-72, manufactured by Cabot Corporation, volume resistivity: 100 Ωcm or less)

[0295] The above materials except the ferrite particles are dispersed in a sand mill to prepare a dispersion, and the dispersion is charged into a vacuum degassing kneader together with the ferrite particles, and dried under reduced pressure with stirring, thereby obtaining a carrier 1.

[0296] <Production of Fluorescent Toner (1)>

[0297] 1.5 parts by mass of hydrophobic silica (RY50 manufactured by Nippon Aerosil Co., Ltd.) and 1.0 parts by mass of hydrophobic titanium oxide (T805 manufactured by Nippon Aerosil Co., Ltd.) were mixed and blended using a sample mill at 10,000 rpm (revolutions / minute) for 30 seconds. The mixture was then sieved using a vibrating sieve with a mesh size of 45 μm to prepare a fluorescent toner (1) (toner for electrostatic image development).

[0298] The volume average particle size of the obtained fluorescent toner (1) was 5.8 μm.

[0299] <Production of Electrostatic Image Developer>

[0300] 8 parts of the fluorescent toner (1) and 92 parts of the carrier were mixed with a V-type blender to prepare a fluorescent developer 1 (electrostatic image developer).

[0301] <Preparation of Colored Colorant Particle Dispersion (2)>

[0302] Colored colorant (CI Pigment Yellow 74): 70 parts

[0303] Anionic surfactant (Neogen RK, manufactured by Daiichi Kogyo Chemical Co., Ltd.): 30 parts

[0304] Ion exchange water: 200 parts

[0305] The above materials were mixed and dispersed for 10 minutes using a homogenizer (ULTRA-TURRAX T50 manufactured by IKA Co.), and ion exchange water was added so that the solid content in the dispersion became 20% by mass to obtain a colored colorant particle dispersion (2) in which colorant particles having a volume average particle size of 140 nm were dispersed.

[0306] <Preparation of Colored Colorant Particle Dispersion (3)>

[0307] A fluorescent colorant particle dispersion (3) was obtained in the same manner as in the preparation of the fluorescent colorant particle dispersion (1) except that 70 parts of the colored colorant (CI Pigment Red 122) was replaced with 70 parts of the colored colorant (CI Pigment Blue 15:3).

[0308] <Production of Colored Toner Particles (1)>

[0309] Resin particle dispersion (1): 44.50 parts

[0310] Colored colorant particle dispersion (2): 7.00 parts

[0311] Release agent particle dispersion (1): 10.00 parts

[0312] Anionic surfactant (Daiichi Kogyo Chemical Co., Ltd.: NEOGEN RK, 20%): 0.20 parts

[0313] The above materials were placed in a round stainless steel flask, 0.1N (= mol / L) nitric acid was added to adjust the pH to 3.5, and then 30 parts of a nitric acid aqueous solution with a polyaluminium chloride concentration of 10% by mass was added. Then, a homogeniser (manufactured by IKA, trade name ULTRA-TURRAX T50) was used to disperse the mixture at a liquid temperature of 30°C, and then the mixture was heated to 45°C in a heating oil bath and maintained for 10 minutes. Thereafter, 38.30 parts of a resin particle dispersion (1) was added and maintained for 1 hour, and a 0.1N sodium hydroxide aqueous solution was added to adjust the pH to 8.5, and then the mixture was heated to 84°C and maintained for 2.5 hours. Then, the mixture was cooled to 20°C at a rate of 20°C / min, the solid content was filtered out, and the mixture was fully washed with ion exchange water and dried to obtain coloured toner particles (1). The volume average particle size of the coloured toner particles (1) was 4.70 μm.

[0314] <Production of Colored Toner (1)>

[0315] With respect to 100 parts by mass of the obtained colored toner particles (1), 1.5 parts by mass of hydrophobic silica (RY50 manufactured by Nippon Aerosil Co., Ltd.) and 1.0 parts by mass of hydrophobic titanium oxide (T805 manufactured by Nippon Aerosil Co., Ltd.) were mixed and blended at 10,000 rpm (revolutions / minute) for 30 seconds using a sample mill. Thereafter, the mixture was sieved using a vibrating sieve having a mesh size of 45 μm to prepare a colored toner (1) (toner for electrostatic image development). The volume average particle size of the obtained colored toner (1) was 4.7 μm.

[0316] <Production of Electrostatic Image Developer>

[0317] 8 parts of the color toner (1) and 92 parts of the carrier were mixed with a V-type blender to prepare a color developer 1 (electrostatic image developer).

[0318] The obtained fluorescent toner (1) and color toner (1) are used as a toner combination for electrostatic image development of Example 1, and the obtained fluorescent developer 1 and color developer 1 are used as a developer combination for electrostatic image of Example 1.

[0319] <Production of Fluorescent Toner Particles (2)>

[0320] Fluorescent toner particles (2) were prepared in the same manner as in the preparation of the fluorescent toner particles (1) except that the mixture was heated to 45° C. and maintained in a heating oil bath for 40 minutes and then heated to 84° C. and maintained for 1.5 hours.

[0321] <Production of Fluorescent Toner Particles (3)>

[0322] Fluorescent toner particles (3) were prepared in the same manner as in the preparation of the fluorescent toner particles (1), except that the mixture was heated to 45° C. in a heating oil bath and maintained for 25 minutes.

[0323] <Production of Fluorescent Toner Particles (4)>

[0324] Fluorescent toner particles (4) were prepared in the same manner as in the preparation of the fluorescent toner particles (1) except that the mixture was heated to 45°C and maintained in a heating oil bath for 60 minutes and then heated to 84°C and maintained for 0.5 hours.

[0325] <Production of Fluorescent Toner Particles (5)>

[0326] Fluorescent toner particles (5) were prepared in the same manner as in the preparation of the fluorescent toner particles (1) except that the mixture was heated to 45°C and maintained in a heating oil bath for 120 minutes and then heated to 84°C and maintained for 1.0 hour.

[0327] <Production of Fluorescent Toner Particles (6)>

[0328] Fluorescent toner particles (6) were prepared in the same manner as in the preparation of the fluorescent toner particles (1) except that the mixture was heated to 45°C and maintained in the heating oil bath for 90 minutes and then heated to 84°C and maintained for 0.5 hours.

[0329] <Production of Fluorescent Toner Particles (7)>

[0330] Fluorescent toner particles (7) were obtained in the same manner as in the preparation of the fluorescent toner particles (2) except that 1.00 part of the fluorescent colorant particle dispersion (1) was replaced with 1.00 part of the fluorescent colorant particle dispersion (2).

[0331] <Production of Fluorescent Toner Particles (8)>

[0332] Fluorescent toner particles (8) were prepared in the same manner as in the preparation of the fluorescent toner particles (1), except that the mixture was heated to 45° C. in a heating oil bath and maintained for 5 minutes.

[0333] <Production of Fluorescent Toner Particles (9)>

[0334] Fluorescent toner particles (9) were prepared in the same manner as in the preparation of the fluorescent toner particles (1) except that the amount of the fluorescent colorant particle dispersion (1) was changed from 1.00 parts to 1.10 parts.

[0335] <Production of Colored Toner Particles (2)>

[0336] Colored toner particles (2) were prepared in the same manner as in the preparation of the colored toner particles (1) except that the mixture was heated to 45° C. in a heating oil bath and maintained for 5 minutes.

[0337] <Production of Colored Toner Particles (3)>

[0338] Colored toner particles (3) were prepared in the same manner as in the preparation of the colored toner particles (1), except that the mixture was heated to 45° C. in a heating oil bath and maintained for 12 minutes.

[0339] <Production of Colored Toner Particles (4)>

[0340] Colored toner particles (4) were prepared in the same manner as in the preparation of the colored toner particles (1), except that the mixture was heated to 45° C. in a heating oil bath and maintained for 25 minutes.

[0341] <Production of Colored Toner Particles (5)>

[0342] Colored toner particles (5) were prepared in the same manner as in the preparation of the colored toner particles (1), except that the mixture was heated to 45° C. in a heating oil bath and maintained for 30 minutes.

[0343] <Production of Colored Toner Particles (6)>

[0344] Colored toner particles (6) were prepared in the same manner as in the preparation of the colored toner particles (1), except that the mixture was heated to 45° C. in a heating oil bath and maintained for 20 minutes.

[0345] <Production of Colored Toner Particles (7)>

[0346] Colored toner particles (7) were prepared in the same manner as in the preparation of the colored toner particles (1) except that 5.0 parts of the colored colorant particle dispersion (3) was used instead of 7.00 parts of the colored colorant particle dispersion (2).

[0347] (Example 2)

[0348] Except for changing the fluorescent color toner particles (1) to fluorescent color toner particles (2) and changing the colored color toner particles (1) to colored color toner particles (2), the fluorescent color toner, fluorescent color developer, colored color toner and colored developer are prepared in the same manner as in Example 1, and the toner combination for electrostatic image development of Example 2 and the electrostatic image developer combination of Example 2 are prepared.

[0349] (Example 3)

[0350] Except for changing the fluorescent color toner particles (1) to fluorescent color toner particles (3) and changing the colored color toner particles (1) to colored color toner particles (3), the fluorescent color toner, fluorescent color developer, colored color toner and colored developer are prepared in the same manner as in Example 1, and the toner combination for electrostatic image development of Example 3 and the electrostatic image developer combination of Example 3 are prepared.

[0351] (Example 4)

[0352] Except for changing the fluorescent color toner particles (1) to fluorescent color toner particles (7), the fluorescent color toner, fluorescent color developer, colored toner and colored developer are prepared in the same manner as in Example 1, and the toner combination for electrostatic image development of Example 4 and the electrostatic image developer combination of Example 4 are prepared.

[0353] (Example 5)

[0354] Except for changing the fluorescent color toner particles (1) to fluorescent color toner particles (9), the fluorescent color toner, fluorescent color developer, colored color toner and colored developer are prepared in the same manner as in Example 1, and the electrostatic image developing toner combination of Example 5 and the electrostatic image developer combination of Example 5 are prepared.

[0355] (Example 6)

[0356] Except for changing the colored toner particles (1) to colored toner particles (7), a fluorescent toner, a fluorescent developer, a colored toner and a colored developer are prepared in the same manner as in Example 1, and the toner combination for electrostatic image development of Example 6 and the electrostatic image developer combination of Example 6 are prepared.

[0357] (Comparative Example 1)

[0358] Except for changing the fluorescent color toner particles (1) to fluorescent color toner particles (4) and changing the colored color toner particles (1) to colored color toner particles (4), the fluorescent color toner, fluorescent color developer, colored color toner and colored developer are prepared in the same manner as in Example 1, and the electrostatic image developing toner combination of Comparative Example 1 and the electrostatic image developer combination of Comparative Example 1 are prepared.

[0359] (Comparative Example 2)

[0360] Except for changing the fluorescent color toner particles (1) to fluorescent color toner particles (5) and changing the colored color toner particles (1) to colored color toner particles (5), the fluorescent color toner, fluorescent color developer, colored color toner and colored developer are prepared in the same manner as in Example 1, and the electrostatic image developing toner combination of Comparative Example 2 and the electrostatic image developer combination of Comparative Example 2 are prepared.

[0361] (Comparative Example 3)

[0362] Except for changing the fluorescent color toner particles (1) to fluorescent color toner particles (6) and changing the colored color toner particles (1) to colored color toner particles (6), the fluorescent color toner, fluorescent color developer, colored color toner and colored developer are prepared in the same manner as in Example 1, and the electrostatic image developing toner combination of Comparative Example 3 and the electrostatic image developer combination of Comparative Example 3 are prepared.

[0363] (Comparative Example 4)

[0364] Except for changing the fluorescent color toner particles (1) to fluorescent color toner particles (8) and changing the colored color toner particles (1) to colored color toner particles (4), the fluorescent color toner, fluorescent color developer, colored color toner and colored developer are prepared in the same manner as in Example 1, and the electrostatic image developing toner combination of Comparative Example 4 and the electrostatic image developer combination of Comparative Example 4 are prepared.

[0365] The following evaluations were performed using the obtained electrostatic image developing toner sets or electrostatic image developer sets of Examples 1 to 6 and Comparative Examples 1 to 4. The evaluation results are summarized in Table 1.

[0366] <Evaluation method>

[0367] The obtained electrostatic image developing toner set and electrostatic image developer set were used to fill an image forming apparatus "Docu Centre Color 400 manufactured by Fuji Xerox Co., Ltd.", respectively.

[0368] The image forming apparatus was used to output a two-color overlapping solid image of 100% fluorescent toner image density + 100% colored toner image density. Nine random locations in the output image were measured using an X-Rite 938 (aperture 4 mm) manufactured by X-Rite Corporation to determine the L * a * b * The value and the spectral reflectance (400 nm to 700 nm) are obtained, and the maximum spectral reflectance in the wavelength range of 400 nm to 700 nm is further obtained for the spectral reflectance.

[0369] -Color reproducibility (intra-plane color difference) evaluation-

[0370] Calculate the L measured at 9 locations * a * b * The average value of the values ​​and the maximum color difference ΔE of each measured value were evaluated according to the following criteria.

[0371] A: 0≦ΔE<1

[0372] B: 1≦ΔE<2

[0373] C: 2≦ΔE<3

[0374] D: 3≦ΔE

[0375] -Evaluation of fluorescence (fluorescence intensity)-

[0376] The average value of the maximum spectral reflectance values ​​measured at nine locations and the maximum difference ΔR between the measured values ​​were calculated and evaluated according to the following criteria.

[0377] A: 0≦ΔR<1

[0378] B: 1≦ΔR<2

[0379] C: 2≦ΔR<3

[0380] D: 3≦ΔR

[0381] -Image quality (color richness, graininess, and image loss) evaluation-

[0382] In addition, the image forming apparatus was used to output the (Japan) Electrophotographic Society test chart No. 5-1. For the multi-color halftone image portion from +0.1 to +1.8 in the output image, the L values ​​of 10 locations were calculated using X-Rite 939 (aperture 4 mm) manufactured by X-Rite Corporation. * Further, the toner loading amount (g / m 2 ). Here, L * Value relative to toner loading (g / m 2 ) and perform quadratic polynomial approximation to obtain the square value of the correlation coefficient, i.e., R2. The R2 value was used to perform evaluation according to the following evaluation criteria.

[0383] A: 0.99≦R2≦1.0

[0384] B: 0.98≦R2<0.99

[0385] C: 0.96≦R2<0.98

[0386] D: R2<0.96

[0387]

[0388] In addition, in Table 1, PY74 represents CI Pigment Yellow 74, PB15:3 represents CI Pigment Blue 15:3, BV11:4 represents Basic Violet 11:4, and BR1:1 represents Basic Red 1:1.

[0389] As shown in the results in Table 1, the resin particle combination (toner combination for electrostatic image development) of this example provides an image with excellent color reproducibility compared with the resin particle combination (toner combination for electrostatic image development) of the comparative example.

[0390] Furthermore, as can be seen from the results shown in Table 1, the images obtained with the resin particle combination (toner combination for electrostatic image development) of this example have high fluorescence intensity and excellent image quality.

[0391] (Example 7)

[0392] -Production of coated products-

[0393] On a 10 cm × 10 cm square test plate of zinc phosphate treated steel plate, a corona gun manufactured by Asahi Suntec Co., Ltd. was used to apply the fluorescent resin particles and the colored resin particles in the resin particle combination of Example 1 respectively by sliding the corona gun up, down, left, and right in a manner such that the coating film thickness was 30 μm to 50 μm, and then baked at 180°C for 30 minutes to produce a coated product.

[0394] In the produced coated product, the powder adhered to the coated product (zinc phosphate treated steel sheet), and it was confirmed that the coating was performed.

[0395] The above description of the embodiments of the present invention is intended to be illustrative and descriptive. It is not intended to be exhaustive or to limit the present invention to the specific embodiments disclosed. It is obvious that a person skilled in the art may make various modifications or changes thereto. The selected and described embodiments are intended to best illustrate the principles of the present invention and its practical application so that other persons skilled in the art can understand the various embodiments of the present invention and make various modifications suitable for the desired specific application. The scope of the present invention is intended to be defined by the claims and their equivalents.

Claims

1. A resin particle combination, comprising: Fluorescent color resin particles containing a fluorescent colorant, and Colored resin particles containing a colored colorant, The volume average particle size of the fluorescent resin particles is larger than the volume average particle size of the colored resin particles. The average roundness of the fluorescent resin particles is 0.93 or more. The volume average particle size of the fluorescent resin particles is greater than 2 μm and less than 10 μm. The volume average particle size of the colored resin particles is 2 μm or more and less than 10 μm. The difference between the volume average particle size of the fluorescent resin particles and the volume average particle size of the colored resin particles is 0.1 μm or more. The above volume average particle size is D 50v .

2. The resin particle combination according to claim 1, wherein The volume ratio of the resin particles having a particle size of 4 μm or less contained in the fluorescent resin particles is 6% or less.

3. The resin particle combination according to claim 1 or claim 2, wherein: The difference between the volume average particle size of the fluorescent resin particles and the volume average particle size of the colored resin particles is 0.3 μm or more.

4. The resin particle combination according to claim 1 or claim 2, wherein: The fluorescent colorant is a fluorescent dye.

5. The resin particle combination according to claim 4, wherein: The fluorescent dyes mentioned above include fluorescent dyes having a maximum fluorescence wavelength in the range of 580 nm to 650 nm.

Images