Toner, toner storage unit, image forming apparatus, and image forming method

Abstract

To provide an antiviral toner with high safety with which an image having antiviral properties can be stably formed.SOLUTION: An antiviral toner is formed of toner particles including a binder resin and an antiviral agent. The antiviral agent contains particles composed of CuI and inorganic dispersant including Zr. The specific gravity of the inorganic dispersant is within a range of ±0.5 of the specific gravity of CuI. The binder resin is a polyester resin. The number average particle diameter of the antiviral agent dispersed in the polyester resin is 500 nm or less. In fluorescent X-ray measurement of the toner particles, the X-ray intensity of Cu is 300 kcps or more, and the intensity ratio of the X-ray intensity of Zr to the X-ray intensity of Cu (Zr / Cu) is larger than 1.0.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a toner, a toner storage unit, an image forming apparatus, and an image forming method. [Background technology]

[0002] In the electrophotographic method of developing an electrostatic latent image with a developer to form a visible image, an electrostatic latent image is formed on an electrostatic latent image carrier, the electrostatic latent image is developed with a developer containing toner to form a toner image, the toner image is transferred to a transfer material such as paper, and then fixed by applying heat and pressure to form a fixed image.

[0003] As described above, the method of fixing an image by heat is suitable in situations where there is concern about viral infections, such as those caused by the recent coronavirus or influenza virus, and can be easily and safely applied to situations where people come into contact with wallpaper, sheets, printed materials in hospitals, packaging materials, etc.

[0004] Patent Document 1 describes a resin composition containing an antibacterial and antiviral agent consisting of fine particles of a monovalent copper compound coated with a dispersant of an inorganic compound. Furthermore, Patent Document 2 describes an antibacterial and antiviral toner containing a silver-based antibacterial material and a pigment. Summary of the Invention [Problem to be solved by the invention]

[0005] The technique described in Patent Document 1 involves kneading first masterbatch pellets, which are resin pellets containing an antibacterial and antiviral agent, with second masterbatch pellets, which are a mixture of a hydrophilic compound and base resin pellets in a predetermined weight ratio, to obtain a resin composition. This technique is not related to toner. Meanwhile, the technique described in Patent Document 2 involves the combined use of a silver-based antibacterial agent and a dye.

[0006] An object of the present invention is to provide a highly safe antiviral toner that can stably form an image having antiviral properties. [Means for solving the problem]

[0007] The toner of the present invention as a means for solving the above problems is as described below. An antiviral toner comprising toner particles containing a binder resin and an antiviral agent, The antiviral agent contains particles composed of CuI and an inorganic dispersant containing Zr, The specific gravity of the inorganic dispersant is within ±0.5 of the specific gravity of CuI, The binder resin is a polyester resin, the number average particle size of the antiviral agent dispersed in the polyester resin is 500 nm or less, In a fluorescent X-ray measurement of the toner particles, the X-ray intensity of Cu is 300 kcps or more, and the intensity ratio of the X-ray intensity of Zr to the X-ray intensity of Cu (Zr / Cu) is greater than 1.0. An antiviral toner characterized by: [Effects of the Invention]

[0008] According to the present invention, it is possible to provide a highly safe antiviral toner that can stably form an image having antiviral properties. [Brief explanation of the drawings]

[0009] [Figure 1] Figure 1 shows a Cu element mapping image of a toner particle obtained by EDX. [Figure 2] FIG. 2A is a mapping image of Cu elements in a toner that does not use a masterbatch, and FIG. 2B is a mapping image of Cu elements in a toner that uses a masterbatch. [Figure 3] FIG. 3 is a schematic diagram showing an example of an image forming apparatus according to an embodiment of the present invention. [Figure 4]FIG. 4 is a schematic diagram for explaining the configuration of the main parts of an embodiment of an image forming apparatus. [Figure 5] FIG. 5 is a schematic diagram showing the main configuration of another example of an image forming apparatus having five developing units. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, embodiments of the present invention will be described in detail. Note that the embodiments are not limited by the following description and can be modified as appropriate without departing from the spirit of the present invention. Furthermore, in this specification, a tilde "~" indicating a numerical range means that the numerical values ​​before and after it are included as the lower and upper limits, unless otherwise specified.

[0011] (toner) The antiviral toner of the present invention comprises toner particles containing a binder resin and an antiviral agent, the antiviral agent containing particles composed of CuI and an inorganic dispersant containing Zr, and optionally contains a release agent, a charge control agent, and other components.

[0012] <Inorganic dispersant> As inorganic dispersants, the inorganic oxides shown in Table 1 below can be mentioned as candidates. [Table 1]

[0013] From the viewpoint of uniform mixing with the antiviral material, it is preferable that the specific gravity of the inorganic dispersant is within ±0.5 of the specific gravity of CuI. From the viewpoint of coloring of the toner, the inorganic dispersant is more preferably colorless or white. From the viewpoint of toner storage stability, it is more preferable that the inorganic dispersant does not have too high moisture adsorption. Considering the above, zirconium oxide is the most preferable inorganic dispersant.

[0014] From the viewpoint of antiviral function, in fluorescent X-ray measurement of toner particles, the Cu X-ray intensity needs to be 300 kcps or more, more preferably 400 kcps or more, and even more preferably 600 kcps or more. Furthermore, the intensity ratio (Zr / Cu) between the X-ray intensity of Zr and the X-ray intensity of Cu must be greater than 1.0, preferably 2.0 or more and 6.0 or less, and more preferably 2.0 or more and 5.0 or less.

[0015] <cui> There are many antibacterial materials available in the world, but only a limited number of them are both effective and safe in terms of antiviral properties. Antibacterial and antiviral tests are specified by the JIS, and certification and registration by the Society of International Antibacterial Articles (SIAA) is the general standard. Among these, the certification requirements for antiviral properties are stricter than those for antibacterial properties. Furthermore, it has been difficult to find a compound that combines the effectiveness of antiviral performance with safety, chargeability in toner, light resistance, and heat-resistant storage.

[0016] As a result of extensive investigations, the inventors have found that by using a binder resin and a specific antiviral agent, it is possible to uniformly disperse and introduce the antiviral agent into a toner, and to achieve high antiviral performance while satisfying the basic properties of a toner and achieving resistance to light resistance and high-temperature, high-humidity storage stability.

[0017] There is a difference due to the dispersion state between the X-ray intensity of the raw materials Cu and I alone and the X-ray intensity of Cu and I when dispersed in toner. In the present invention, the net X-ray intensity of Cu and I in the toner is defined as the X-ray intensity of Cu and I. In the following, "X-ray intensity" may be referred to as "intensity."

[0018] <Charge control agent> Any commonly used charge control agent (hereinafter referred to as CCA) may be used, and a colorless or white CCA is preferred. Furthermore, zirconium salicylate or the like may be used as the metal-containing CCA. When zirconium oxide is used as the inorganic dispersant for CuI, zirconium oxide and zirconium salicylate are mixed, but zirconium salicylate is dispersed separately from CuI in the toner and hardly functions as a dispersant for CuI, so there is no particular problem with using them together. However, when zirconium salicylate is used as the CCA, the content of zirconium salicylate in the toner is preferably 2% by mass or less, and more preferably 1.2% by mass or less, so as not to significantly affect the intensity ratio (Zr / Cu) of the X-ray intensity of Zr derived from the inorganic dispersant containing zirconium to the X-ray intensity of Cu.

[0019] <Fluorescent X-ray measurement method> There are no particular limitations on the method for measuring the X-ray intensity of metal elements such as Cu and Zr, and any method can be selected appropriately depending on the purpose. In the present invention, the Cu and Zr intensities (kcps) of the metal elements can be determined using the following apparatus and conditions. First, 3.00 g of toner is molded into a pellet with a diameter of 3 mm and a thickness of approximately 2 mm. If the specific gravity is quite high, the toner weight is converted into specific gravity and molded into a thickness of approximately 2 mm to serve as the measurement sample. Prior to measurement, it is preferable to perform calibration using a standard sample of the metal being measured (manufactured by Rigaku Corporation), but this does not pose any particular problems as long as it is properly managed. Qualitative analysis of the measurement sample is performed using an X-ray fluorescence analyzer, and the net intensity of the Cu-Kα ray type is calculated as the Cu intensity (kcps) value. The same procedure is used to determine Zr and Al. Measurement equipment: Rigaku Corporation, ZSX Primus IV ·X-ray tube: Rh X-ray tube voltage: 50kV ·X-ray tube current: 10mA Measurement mode: EZ scan, Sample type: Polymer, Measurement range: F to U Measurement diameter: 30 mm, measurement time: standard. The type of radiation does not need to be particularly limited as long as it has detection accuracy that allows for relative comparison, but from the viewpoint of measurement accuracy and sensitivity, it is preferable to basically use the net intensity with Kα radiation. The intensity values ​​used in this case are shown as the net intensity with Kα radiation for metal elements specific to the material.

[0020] The antiviral agent comprises CuI particles, an antiviral material, and a dispersant that coats the CuI particles to prevent aggregation or supports the CuI particles on its surface. While organic compounds such as polymeric dispersants, surfactants, and plasticizers, as well as inorganic compounds such as metal soaps, can be used as dispersants, in this embodiment, inorganic compounds are preferred because they can enhance contact with bacteria and viruses and facilitate the development of antibacterial and antiviral effects. For example, inorganic compounds such as zirconia, aluminum oxide, and titanium oxide have a positive zeta potential at pH 7, while viruses generally have a negative potential. Therefore, coating copper compound microparticles with these inorganic compound microparticles enhances contact between the antiviral agent and viruses, thereby facilitating the development of antiviral effects. Furthermore, coating the copper compound microparticles with an inorganic compound makes them less susceptible to oxidation, thereby prolonging the antibacterial and antiviral effects.

[0021] The number average particle size of the antiviral agent is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 10 nm to 500 nm, more preferably 10 nm to 300 nm. A number average particle size of 10 nm or more prevents an increase in surface area, thereby reducing deterioration in lightfastness and discoloration of the toner. A number average particle size of 500 nm or less prevents insufficient antiviral properties due to an increase in the number average particle size, reduces wear within the device during toner production, and prevents deterioration in manufacturability. Furthermore, metal elements such as SUS of the device, particularly Cr and Fe, are not contained in the toner, preventing effects such as discoloration of the toner itself to gray. However, in the present invention, the average dispersed particle size (including the aggregated state) of the antiviral agent is expressed as the number-average particle size calculated by mapping of Cu elements in EDX.

[0022] When a masterbatch containing a masterbatch resin that is incompatible with the binder resin and CuI or a mixture of CuI and an inorganic dispersant is used, the masterbatch resin forms island domains in the toner, and CuI is encapsulated within the masterbatch resin. In this case, an inorganic dispersant may also be used, but there is no particular problem if a small amount or none is used at all. Furthermore, if a masterbatch is made with a resin compatible with the binder resin, a certain amount or more of the inorganic dispersant is required, so as a result, it does not matter whether or not the masterbatch is made.

[0023] When using a resin that is incompatible with the binder resin, select one that is incompatible with the resin that is the main component of the antiviral toner and forms an independent discontinuous phase. In this way, a discontinuous phase of a resin that is incompatible with the binder resin is mixed into the resin that is the main component of the antiviral toner, forming a phase-separated structure, which improves the antibacterial and antiviral effects when it comes into contact near the surface of the toner or near the surface of an image formed on it. In order to improve the diffusibility of viruses and bacteria, the resin is preferably hydrophilic to some extent. Examples of resins that are incompatible with the binder resin contained in the antiviral toner include water-soluble synthetic polymers such as polyvinyl alcohol (PVA), polyvinylpyrrolidone (PVP), polyethylene oxide (PEO), hydroxypropyl cellulose (HPC), polyethylene glycol (PEG), polyacrylamide (PAAM), polyacrylic acid (PAA), sodium polyacrylate, and polyethyleneimine; carboxymethyl starch, dialdehyde starch, alginate, polystyrene sulfonate, carboxymethyl cellulose (CMC), polysaccharides, polyoxyethylene-polyoxypropylene copolymers, poly-N-alkylacrylamides, hydroxyethyl cellulose, poly-N-isopropylacrylamide (PNIAAm), chondroitin sulfate, dextran sulfate, dermatan sulfate, methyl vinyl ether-maleic anhydride copolymer, ethylene-vinyl acetate copolymer, and acrylamide-acrylate copolymers such as dimethylacrylamide-glycidyl methacrylate copolymer.

[0024] By supporting CuI in the toner and on the toner surface while suppressing its release during pulverization, it becomes possible for CuI to be present on the toner surface and in the vicinity of the image surface during image formation. However, if only antibacterial performance is required, there is no particular problem with using an incompatible masterbatch resin, but when it comes to antiviral effects, the action against viruses due to this domain dispersion state becomes insufficient, making it difficult to achieve sufficient antiviral performance.

[0025] Viruses are generally small, and it is important that the range within which an antiviral material can act on a virus, i.e., the distance between antiviral materials is small and that a distance sufficient for the material to act on the virus is ensured. For this reason, a masterbatch method using a resin that is incompatible with the binder resin is likely to result in insufficient antiviral performance.

[0026] A general surfactant can also be used as a dispersant. However, if dispersed in the toner, the toner may discolor, for example, to a reddish-brown color, when stored at high temperatures and humidity. This is acceptable if there is no problem with the color, but if there is a problem with the color even for colorless, white, or chromatic colors, it is preferable to limit the amount or not use it at all.

[0027] The dispersion state can be evaluated by mapping the toner with EDX using Cu or I. It is also possible to evaluate the dispersion state by mapping the dispersant Zr, but although Zr is suitable for observing synchronization with Cu and I and dispersion within the toner, it is more uniformly dispersed within the toner than synchronization with CuI, so Zr mapping is used to complement the evaluation of the dispersion state of Cu and I. Figure 1 shows a mapping image of Cu elements obtained by analyzing toner particles using EDX (Energy Dispersive X-ray Spectroscopy). Zr is dispersed evenly throughout the toner, and Cu and I are present in the form of small dispersed particles in synchronization with Zr.

[0028] Furthermore, the dispersion state of CuI when a masterbatch is used and when no masterbatch is used can be clearly distinguished by EDX. Figure 2 shows images obtained by EDX analysis of toner particles. Figure 2A is a mapping image of Cu elements for toner that did not use a masterbatch, and Figure 2B is a mapping image of Cu elements for toner that used a masterbatch.

[0029] The method for measuring the number average particle diameter of the antiviral agent in the toner will be described below. <Measurement conditions> The particle size distribution of the antiviral agent in the toner can be measured using a scanning electron microscope (SEM) and an energy dispersive X-ray analyzer (EDX) as follows. Toner is fixed onto carbon tape, and the sample is coated with carbon to prevent charge-up. The sample is observed using a scanning electron microscope (SEM) and an energy dispersive X-ray analyzer (EDX). The observation conditions are as follows: SEM SU8230 manufactured by Hitachi Ltd. and EDX FlashFlatQUAD5060F manufactured by Bruker. Acceleration voltage: 15kv Emission: 20mV Probe current: High Condenser lens: 1.0 WD:11.2 Image magnification: 2000x, 5000x, or 10,000x is arbitrarily selected, and several toner particle candidates are selected as targets. Next, the measurement position is determined at an image magnification of 20,000 times, and the Cu element is mapped on the toner surface using EDX hypermap mode with E(U)+SE(L) set for at least 180 s. The position and size of the Cu element are identified by comparing the toner SEM image displayed by EDX, the Cu mapping image, and a composite image combining the toner SEM image and Cu mapping image. The positions and sizes of Al, Zn, and Sn elements are also identified in the same way. However, in Comparative Example 3 described below, calculations were performed using images mapped with Zn element, in Comparative Example 5 with Al element, and in Comparative Example 6 with Sn element, and all the others used images mapped with Cu element. Alternatively, the average particle size may be determined by binarizing the EDX image mapped with Cu and calculating the particle size using a separate analysis software. In this case, the particle size is calculated using at least 1,000 particles.

[0030] In the present invention, the EDX image mapped with Cu is selected, pasted into an Excel spreadsheet, and the contrast is adjusted in Excel. Note that the brightness and contrast of each image can be adjusted to facilitate binarization. For example, it is recommended to adjust brightness to -15 to +30 and contrast to +10 to +40. Copy the image using snippettool, adjust the scale so that it is about 480 pixels x 360 pixels as a JPEG file, and save the image. Select at least 15 images from this, excluding images that are not suitable for binarization because the toner surface contours are too shady, or images that are not entirely covered by the toner surface. If there is a region other than the particle that is binarized due to elemental display, etc., the numerical value can be corrected by changing the image or, if the region is small and easy to calculate, excluding this region from the calculation. There are no particular limitations on the contrast adjustment and binarization methods, but here, the binarized image is calculated using image processing software Image-ProPlus5.1J (manufactured by Media Cybernetics). The settings and procedures for binarization are as follows: (1) Process > Enhance Contrast and Saturated Specify pixels: 0.3% (2) Binarize using Process → Binary → MakeBinary (3) Image → Adjust → Size: 480*360 pixels ±5% Resize to fit in 8-bit (resizing is only necessary). (4) Save the binary image with a name by selecting File → SaveAs → Jpeg. These binarized images are subjected to image analysis processing using image analysis software: Azokun (manufactured by Asahi Kasei Engineering Co., Ltd.). Transfer the binarized image obtained above and select Particle Analysis from the Image Analysis tab to display the particle analysis parameters. Among the parameters, set the "circle equivalent diameter." Check the particle number and circle equivalent diameter and transfer the data to Excel. The calculation results (number of particles, equivalent circle diameter) for each image are compared with the analysis image, and any images that are clearly incorrectly processed or inappropriate are deleted. Priorities are assigned, and the number of images is selected so that the total number of analyzed particles is 1,000 or more. The average value of the equivalent circle diameter is calculated to determine the number-average particle size of the antiviral agent.

[0031] <Binder resin> The binder resin can be selected appropriately depending on the purpose, so long as its main constituent is a polyester resin. It is not particularly problematic to include resins such as styrene acrylic or olefinic resins as dispersants for other uses in toner, but it is preferable that the content is less than 10% in terms of the degree of influence on CuI. There are no particular restrictions on the acid value of the polyester resin, and examples include low-acid-value resins with an acid value of less than 10 mgKOH / g and high-acid-value resins with an acid value of 15 mgKOH / g or more. The low acid value resin is not particularly limited as long as it has an acid value of less than 10 mgKOH / g, and can be appropriately selected depending on the purpose. Examples include RN-306 (acid value: 7 mgKOH / g, manufactured by Kao Corporation) and RN-306SF (acid value: 8 mgKOH / g, manufactured by Kao Corporation). The high acid value resin is not particularly limited as long as it has an acid value of 15 mgKOH / g or more, and can be appropriately selected depending on the purpose. For example, RN-290 (acid value: 27 mgKOH / g, manufactured by Kao Corporation) can be used.

[0032] The content of the low acid value resin is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 10% by mass or more and 60% by mass or less, and more preferably 25% by mass or more and 50% by mass or less.

[0033] The content of the high acid value resin is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 10% by mass or more and 60% by mass or less, and more preferably 15% by mass or more and 45% by mass or less.

[0034] The polyester resin is not particularly limited and can be appropriately selected depending on the purpose. For example, it may be a resin obtained by condensation polymerization of an alcohol and a carboxylic acid.

[0035] The alcohol is not particularly limited and can be appropriately selected depending on the purpose. Examples thereof include glycols such as ethylene glycol, diene glycol, triethylene glycol, and propylene glycol; etherified bisphenols such as 1,4-bis(hydroxymeta)cyclohexane and bisphenol A; other dihydric alcohol monomers; and trihydric or higher polyhydric alcohol monomers.

[0036] The carboxylic acid is not particularly limited and can be appropriately selected depending on the purpose. Examples thereof include divalent organic acid monomers such as maleic acid, fumaric acid, phthalic acid, isophthalic acid, terephthalic acid, succinic acid, and malonic acid, and trivalent or higher polyvalent carboxylic acid monomers such as 1,2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid, 1,2,4-cyclohexanetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, 1,2,5-hexanetricarboxylic acid, 1,3-dicarboxyl-2-methylenecarboxypropane, and 1,2,7,8-octanetetracarboxylic acid.

[0037] The glass transition point (hereinafter sometimes referred to as "glass transition temperature") Tg of the binder resin is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 50°C or higher and 75°C or lower. The method for measuring the glass transition temperature Tg is not particularly limited and can be appropriately selected depending on the purpose. For example, the glass transition temperature Tg can be measured by DSC.

[0038] <Other binder resins> The toner according to an embodiment may contain binder resin components other than the polyester resin and polyolefin. Examples of other binder resins include known binder resins such as styrene-based resins (homopolymers or copolymers containing styrene or styrene substitutes) such as styrene, poly-α-styrenestyrene, styrene-chlorostyrene copolymer, styrene-propylene copolymer, styrene-butadiene copolymer, styrene-vinyl chloride copolymer, styrene-vinyl acetate copolymer, styrene-maleic acid copolymer, styrene-acrylate copolymer, styrene-methacrylate copolymer, styrene-α-methyl chloroacrylate copolymer, and styrene-acrylonitrile-acrylate copolymer, epoxy resin, vinyl chloride resin, rosin-modified maleic acid resin, phenol resin, polyethylene resin, polypropylene resin, petroleum resin, polyurethane resin, ketone resin, ethylene-ethyl acrylate copolymer, xylene resin, and polyvinyl butyrate resin.

[0039] The method for producing the binder resin is not particularly limited and can be appropriately selected depending on the purpose. For example, known production methods such as bulk polymerization, solution polymerization, emulsion polymerization, and suspension polymerization can be used.

[0040] <Release agent> The release agent is not particularly limited and can be appropriately selected depending on the purpose. Examples include low-molecular-weight polyolefin waxes such as low-molecular-weight polyethylene and low-molecular-weight polypropylene; synthetic hydrocarbon waxes such as Fischer-Tropsch wax; natural waxes such as beeswax, carnauba wax, candelilla wax, rice wax, and montan wax; petroleum waxes such as paraffin wax and microcrystalline wax; higher fatty acids such as stearic acid, palmitic acid, and myristic acid, and metal salts of higher fatty acids; higher fatty acid amides; synthetic ester waxes; and various modified waxes thereof. These can be used alone or in combination of two or more. Among these, carnauba wax and its modified waxes, polyethylene wax, and synthetic ester waxes are preferred.

[0041] The content of the release agent is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 2% by mass or more and 15% by mass or less, and more preferably 2.5% by mass or more and 10% by mass or less, relative to the binder resin of the toner. When the content is 2% by mass or more, hot offset can be prevented, and when it is 15% by mass or less, deterioration in transferability and durability can be prevented. The melting point of the release agent is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 60° C. or higher and 150° C. or lower, and more preferably 65° C. or higher and 120° C. or lower. When the melting point is 60° C. or higher, the deterioration of the heat-resistant storage stability of the toner can be prevented. When the melting point is 150° C. or lower, the release agent can exhibit effective release properties.

[0042] <Charge control agent> The charge control agent is not particularly limited and can be appropriately selected depending on the purpose. Examples thereof include nigrosine and modified products thereof with fatty acid metal salts, onium salts such as phosphonium salts and lake pigments thereof, triphenylmethane dyes and lake pigments thereof, metal salts of higher fatty acids, diorganotin oxides such as dibutyltin oxide, dioctyltin oxide, and dicyclohexyltin oxide, diorganotin borates such as dibutyltin borate, dioctyltin borate, and dicyclohexyltin borate, organometallic complexes, chelate compounds, monoazo metal complexes, acetylacetone metal complexes, aromatic hydroxycarboxylic acids, metal complexes of aromatic dicarboxylic acids, quaternary ammonium salts, salicylic acid metal compounds, aromatic hydroxycarboxylic acids, aromatic mono- and polycarboxylic acids and metal salts thereof, anhydrides, esters, and phenol derivatives such as bisphenol.

[0043] The content of the charge control agent is not particularly limited and can be selected appropriately depending on the purpose, but is preferably 0.1% by mass or more and 10% by mass or less, and more preferably 1% by mass or more and 5% by mass or less, relative to the binder resin of the toner.

[0044] <Other ingredients> The other components are not particularly limited and can be appropriately selected depending on the purpose. Examples thereof include colorants, external additives, flowability improvers, cleaning improvers, and magnetic materials.

[0045] -Coloring agent- The colorant is not particularly limited, and any commonly used colorant can be appropriately selected and used.

[0046] As the black toner, carbon black alone or a mixture of carbon black as the main component and copper phthalocyanine or the like, with the hue and brightness adjusted, is preferred.

[0047] As the cyan toner, copper phthalocyanine with pigment blue 15:3 or a mixture of copper phthalocyanine and aluminum phthalocyanine is preferred.

[0048] As the magenta toner, Pigment Red 53:1, Pigment Red 81, Pigment Red 122, Pigment Red 269, etc. can be used. These may be used alone or in combination of two or more.

[0049] As the yellow toner, Pigment Yellow 74, Pigment Yellow 155, Pigment Yellow 180, Pigment Yellow 185, etc. can be used. These may be used alone or in combination of two or more. Among these, Pigment Yellow 185 or a mixture of Pigment Yellow 74 and Pigment Yellow 185 is preferred in terms of saturation and storage stability.

[0050] As the white pigment, titanium dioxide that has been surface-treated with silicon, zirconia, aluminum, polyol, or the like can be used.

[0051] Pigment Green 7 or the like can be used as the green toner, but safety considerations must be taken into account.

[0052] As the blue toner, Pigment Blue 15:1, Pigment Violet 23, etc. can be used.

[0053] The toner is preferably colorless (containing no colorant), white, or a light color with a slight tint, from the viewpoint of not impairing the color of the toner to be overlaid. Light colors are preferably slightly yellowish, reddish-brown, or grayish. When the toner according to the embodiment is used as a base layer (the layer closest to the recording medium on which an image is formed) and a color toner layer is formed thereon, impairing the color of the color toner can be reduced.

[0054] -External additives- The external additive is not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include inorganic fine particles.

[0055] The inorganic fine particles are not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include silica, alumina, titanium oxide, barium titanate, magnesium titanate, calcium titanate, strontium titanate, zinc oxide, silica sand, clay, mica, wollastonite, diatomaceous earth, chromium oxide, cerium oxide, red iron oxide, antimony trioxide, magnesium oxide, zirconium oxide, barium sulfate, barium carbonate, calcium carbonate, silicon carbide, silicon nitride, etc. Among these, silica, alumina, and titanium oxide are preferred.

[0056] In addition, inorganic fine particles may be surface-treated with a hydrophobic treatment agent. Examples of the hydrophobic treatment agent include silane coupling agents, silylating agents, silane coupling agents having fluorinated alkyl groups, organic titanate coupling agents, and aluminum coupling agents. In addition, sufficient effects can be obtained by using silicone oil as a hydrophobic treatment agent.

[0057] -Flow improver- The flowability improver is not particularly limited as long as it is capable of performing a surface treatment to increase hydrophobicity and prevent deterioration of flowability and charging properties even under high humidity conditions, and can be appropriately selected depending on the purpose. Examples of the flowability improver include silane coupling agents, silylating agents, silane coupling agents having a fluorinated alkyl group, organic titanate coupling agents, aluminum coupling agents, silicone oils, and modified silicone oils. The silica and titanium oxide are preferably surface-treated with such a flowability improver and used as hydrophobic silica and hydrophobic titanium oxide.

[0058] -Cleaning improver- The cleaning property improver is not particularly limited as long as it is added to the toner in order to remove the developer remaining on the photosensitive member or the primary transfer medium after transfer, and can be appropriately selected depending on the purpose. The cleaning property improver is not particularly limited and can be appropriately selected depending on the purpose. Examples thereof include fatty acid metal salts such as zinc stearate, calcium stearate, and stearic acid, and polymer fine particles produced by soap-free emulsion polymerization, such as polymethyl methacrylate fine particles and polystyrene fine particles. The volume average particle size of the polymer particles is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 0.01 μm or more and 1 μm or less in terms of a relatively narrow particle size distribution.

[0059] -Magnetic materials- The magnetic material is not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include iron powder, magnetite, ferrite, etc. Among these, white materials are preferred in terms of color tone.

[0060] <Toner manufacturing method> The toner manufacturing method according to one embodiment includes a step of obtaining a binder resin mixture (mixing step), a step of obtaining a kneaded mixture of the mixture (melting and kneading step), a step of obtaining a solid of the kneaded mixture (solidification step), a step of obtaining a pulverized product of the solid (fine pulverization step), and a step of classifying and recovering the pulverized product (classification step).

[0061] First, a binder resin, a colorant, a release agent, and optionally a charge control agent, etc. are mixed in a mixer such as a Henschel mixer or a super mixer to obtain a mixture (mixing step).

[0062] Next, the mixture is melt-kneaded using a thermal melt kneader such as a heating roll, a kneader, or an extruder to obtain a kneaded product (melt-kneading step).

[0063] Next, the kneaded mixture is cooled and solidified to obtain a solid (solidification step). The cooling method and solidification method are not particularly limited, and any appropriate method can be used.

[0064] Next, the solid is finely pulverized to obtain a pulverized product (fine pulverization step). The solid can be pulverized using a known pulverization method. Examples of pulverization methods that can be used include a jet mill method in which toner is contained in a high-speed airflow and the solid is pulverized by the energy generated when the toner collides with a collision plate, an inter-particle collision method in which toner particles collide with each other in an airflow, and a mechanical pulverization method in which toner is supplied between a narrow gap and a rotor rotating at high speed to pulverize the toner.

[0065] The pulverized product is then classified to recover pulverized products having a predetermined volume average particle size, thereby obtaining a toner (classification step). The classification method is not particularly limited, and any appropriate method can be used.

[0066] The toner according to one embodiment can also be produced using a solution suspension method. When producing the toner using the solution suspension method, an oil phase in which toner materials such as a binder resin, a colorant, a release agent, and optionally a charge control agent are dissolved or dispersed in an organic solvent is dispersed in an aqueous medium (aqueous phase), and the binder resin is reacted. This produces a dispersion containing a dispersion (oil droplets) containing a prepolymer in which the toner materials are emulsified or dispersed. The organic solvent is then removed from the dispersion, and the resulting mixture is filtered, washed, dried, and further classified as necessary to produce toner base particles. The toner according to one embodiment can be obtained by granulating the base particles obtained using the solution suspension method.

[0067] The organic solvent is not particularly limited and can be appropriately selected depending on the purpose, but an organic solvent having a boiling point of less than 150° C. is preferred in terms of ease of removal.

[0068] The organic solvent having a boiling point of less than 150°C is not particularly limited and can be appropriately selected depending on the purpose. Examples include toluene, xylene, benzene, carbon tetrachloride, methylene chloride, 1,2-dichloroethane, 1,1,2-trichloroethane, trichloroethylene, chloroform, monochlorobenzene, dichloroethylidene, methyl acetate, ethyl acetate, methyl ethyl ketone, and methyl isobutyl ketone. These may be used alone or in combination of two or more. Among these, ethyl acetate, toluene, xylene, benzene, methylene chloride, 1,2-dichloroethane, chloroform, and carbon tetrachloride are preferred, with ethyl acetate being more preferred.

[0069] The aqueous medium is not particularly limited and can be appropriately selected depending on the purpose. Examples include water, a solvent miscible with water, and a mixture thereof. These may be used alone or in combination of two or more. Among these, water is preferred.

[0070] The water-miscible solvent can be appropriately selected depending on the purpose, and examples thereof include alcohols, lower ketones, dimethylformamide, tetrahydrofuran, cellosolves, etc. The alcohol is not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include methanol, isopropanol, ethylene glycol, etc. The lower ketone can be appropriately selected depending on the purpose, and examples thereof include acetone, methyl ethyl ketone, etc.

[0071] The method for removing the organic solvent from the dispersion is not particularly limited and can be appropriately selected depending on the purpose. Examples include a method in which the temperature of the entire reaction system is gradually increased to evaporate the organic solvent in the oil droplets, and a method in which the dispersion is sprayed into a dry atmosphere to remove the organic solvent in the oil droplets.

[0072] The classification may be carried out by removing fine particles in the liquid using a cyclone, decanter, centrifugal separation or the like, or the classification operation may be carried out after drying.

[0073] Furthermore, the toner according to one embodiment has a low melting point and is less likely to crystallize, and therefore has excellent heat-resistant storage stability. The heat-resistant storage stability can be evaluated based on the amount of aggregates generated in the toner after storing the toner in a high-temperature and high-humidity environment (e.g., 40°C, 70% RH) for a long period of time (e.g., 14 days).

[0074] <Developer> The developer according to an embodiment includes the toner according to an embodiment, and may include other appropriately selected components such as a carrier, if necessary.

[0075] The developer may be a one-component developer or a two-component developer, but when used in high-speed printers that correspond to the recent improvements in information processing speed, a two-component developer is preferable in terms of extending the developer life.

[0076] When the toner according to one embodiment is used as a single-component developer, even if the toner is balanced, there is little fluctuation in the particle size of the toner, there is little toner filming on the developing roller, and there is little toner fusing to components such as blades that thin the toner layer, and good and stable developability and images can be obtained even with long-term stirring in the developing device.

[0077] When the developer according to an embodiment is used as a two-component developer, it can be mixed with a carrier and used as a developer. When the toner according to an embodiment is used as a two-component developer, the particle size of the toner changes little even when the toner is balanced over a long period of time, and good and stable developability and images can be obtained even when the toner is stirred for a long period of time in a developing device.

[0078] The content of the carrier in the two-component developer can be appropriately selected depending on the purpose, but is preferably 90 parts by mass or more and 98 parts by mass or less, and more preferably 93 parts by mass or more and 97 parts by mass or less, relative to 100 parts by mass of the two-component developer.

[0079] The developer according to one embodiment can be suitably used for image formation by various known electrophotographic methods such as a magnetic one-component development method, a non-magnetic one-component development method, and a two-component development method.

[0080] [Career] Magnetic particles can be used as the carrier. Examples of magnetic particles include spinel ferrites such as magnetite and gamma iron oxide, spinel ferrites containing one or more metals other than iron (e.g., Mn, Ni, Zn, Mg, Cu), magnetoplumbite ferrites such as barium ferrite, and iron or alloy particles having an oxide layer on their surfaces. Considering chemical stability, magnetoplumbite ferrites such as magnetite, spinel ferrites containing gamma iron oxide, and barium ferrite are preferred. Specific examples include MFL-35S, MFL-35HS (manufactured by Powder Tech Co., Ltd.), DFC-400M, DFC-410M, and SM-350NV (manufactured by Dowa Iron Powder Co., Ltd.).

[0081] In particular, when high magnetization is required for the carrier, it is preferable to use fine ferromagnetic particles such as iron as the carrier.

[0082] The shape of the carrier may be any of granular, spherical, and needle-like.

[0083] By appropriately selecting the type and content of the carrier, a resin carrier having the desired magnetization can be used. In this case, the magnetic properties of the resin carrier are preferably such that the magnetization strength at 1,000 oersted is 30 emu / g to 150 emu / g.

[0084] Such a resin carrier can be produced by spraying a molten mixture of a carrier and an insulating binder resin using a spray dryer, or by reacting and curing a monomer or prepolymer in an aqueous medium in the presence of the carrier, thereby producing a resin carrier in which the carrier is dispersed in a condensation binder.

[0085] The chargeability can be controlled by adhering positively or negatively chargeable fine particles or conductive fine particles to the surface of the carrier, or by coating the surface with a resin.

[0086] Examples of surface coating materials (resins) that can be used include silicone resins, acrylic resins, epoxy resins, fluorine-based resins, etc. Furthermore, coatings containing positively or negatively charged particles or conductive particles can also be used, and among these, silicone resins and acrylic resins are preferred.

[0087] The weight ratio of the carrier in the developer contained in the developing device is preferably 85% by mass to less than 98% by mass. If the weight ratio is 85% by mass or more but less than 98% by mass, scattering of toner from the developing device is easily suppressed, and the occurrence of defective images can be reduced. In addition, an excessive increase in the charge amount of the electrophotographic toner and an insufficient supply of the electrophotographic toner can be suppressed, thereby reducing the occurrence of defective images due to a decrease in image density.

[0088] <Developer container> The developer storage container according to an embodiment stores the developer according to an embodiment. The developer storage container is not particularly limited and can be appropriately selected from known containers, and examples thereof include a container having a container body and a cap.

[0089] The size, shape, structure, material, etc. of the container body are not particularly limited. The container body is preferably cylindrical, such as a cylinder, and has a spirally formed uneven portion on the inner circumferential surface. By rotating the container body, the developer contained therein can be easily transferred to the outlet side. It is more preferable that some or all of the uneven portion be formed in a bellows shape. This makes it easier for the developer to move to the discharge port side. Furthermore, although the material is not particularly limited, it is preferable that it has good dimensional accuracy, and examples of the material include resin materials such as polyester resin, polyethylene resin, polypropylene resin, polystyrene resin, polyvinyl chloride resin, polyacrylic acid, polycarbonate resin, ABS resin, and polyacetal resin.

[0090] The developer storage container is easy to store, transport, and handle, and can be detachably attached to an image forming apparatus, a process cartridge, or the like, which will be described later, and used to replenish the developer.

[0091] <Toner set> The toner set according to an embodiment can include a color toner containing a binder resin and a colorant, and the toner according to an embodiment.

[0092] The color toner is not particularly limited, and a known color toner can be appropriately selected depending on the purpose. The binder resin is not particularly limited, and can be appropriately selected depending on the purpose, and can be the same as the binder resin contained in the toner according to one embodiment. The colorant is not particularly limited, and a known colorant can be appropriately selected depending on the purpose.

[0093] By attaching the toner set according to one embodiment to an image forming device and forming an image, the image is formed using the toner according to one embodiment, and therefore, image formation can be performed by taking advantage of the characteristics of the toner, which has excellent fixing properties to fabric.

[0094] <Toner storage unit> The toner storage unit according to an embodiment can store the toner according to an embodiment. The toner storage unit according to an embodiment refers to a unit that stores toner in a unit having a function of storing toner. Here, examples of the toner storage unit include a toner storage container, a developing unit, and a process cartridge.

[0095] The toner container refers to a container that stores toner.

[0096] The developing device is a device that contains toner and has means for developing.

[0097] A process cartridge is a device that integrates at least an electrostatic latent image carrier (also called an image carrier) and a developing means, contains toner, and is detachably mountable to an image forming apparatus. The process cartridge may further include at least one selected from a charging means, an exposure means, a cleaning means, etc.

[0098] The toner storage unit according to the embodiment stores the toner according to the embodiment. By mounting the toner storage unit according to the embodiment in an image forming apparatus and forming an image, the toner according to the embodiment is used to form an image, making it possible to form an image that takes advantage of the characteristics of the toner, which has excellent fixing properties to fabric.

[0099] (Toner storage unit) The toner storage unit in the present invention refers to a unit having a function of storing toner and storing the toner of the present invention. Examples of the toner storage unit include a toner storage container, a developing unit, and a process cartridge.

[0100] The toner storage container refers to a container that stores toner. When the toner is used as a developer, the toner container may be referred to as a developer container. The developer container is not particularly limited and can be appropriately selected from known containers, and examples thereof include a container having a container body and a cap.

[0101] The size, structure, material, etc. of the container body of the toner container and the developer container are not particularly limited. The shape of the container body of the developer storage container is not particularly limited and can be appropriately selected depending on the purpose, but it is preferably cylindrical, such as cylindrical, and has a spirally formed uneven portion on the inner circumferential surface. By rotating the container body, the developer contained therein can be easily transferred to the discharge port side. Furthermore, it is more preferable that part or all of the uneven portion is formed in a bellows shape. This makes it easier for the developer to be transferred to the discharge port side.

[0102] The materials for the toner storage container and the developer storage container are not particularly limited and can be appropriately selected depending on the purpose, but it is preferable that they have good dimensional accuracy, and examples of such materials include resin materials such as polyester resin, polyethylene resin, polypropylene resin, polystyrene resin, polyvinyl chloride resin, polyacrylic acid, polycarbonate resin, ABS resin, and polyacetal resin.

[0103] The toner storage container and the developer storage container are easy to store, transport, etc., and are easy to handle, so they can be detachably attached to the image forming apparatus, process cartridge, etc. described below, and used to replenish toner and developer.

[0104] The developing device has a means for storing toner and developing the toner. The process cartridge is a cartridge that integrates at least an electrostatic latent image carrier (also referred to as an image carrier) and a developing means, contains toner, and is detachably mountable to an image forming apparatus. The process cartridge may further include at least one selected from a charging unit, an exposure unit, a cleaning unit, etc.

[0105] (Image forming apparatus and image forming method) The image forming apparatus according to the present invention includes an electrostatic latent image carrier, an electrostatic latent image forming unit that forms an electrostatic latent image on the electrostatic latent image carrier, a developing unit that develops the electrostatic latent image formed on the electrostatic latent image carrier with toner to form a toner image, a transfer unit that transfers the toner image to a recording medium, and a fixing unit that fixes the transferred image transferred to the recording medium, and may further include other units as necessary.

[0106] The image forming method of the present invention comprises an electrostatic latent image forming step of forming an electrostatic latent image on an electrostatic latent image carrier, a developing step of developing the electrostatic latent image to form a toner image, a transfer step of transferring the toner image to a recording medium, and a fixing step of fixing the transferred image transferred to the recording medium, wherein the toner image is formed by the toner of the present invention, and may comprise other steps as necessary.

[0107] The image forming method can be suitably performed by the image forming apparatus, the electrostatic latent image forming step can be suitably performed by the electrostatic latent image forming unit, the developing step can be suitably performed by the developing unit, the transfer step can be suitably performed by the transfer unit, the fixing step can be suitably performed by the fixing unit, and the other steps can be suitably performed by the other units.

[0108] <Electrostatic latent image carrier> The material, structure, and size of the electrostatic latent image carrier (hereinafter sometimes referred to as "photoreceptor") are not particularly limited, and can be appropriately selected from known materials. Examples of the material for the electrostatic latent image bearing member include an inorganic photoreceptor and an organic photoreceptor. The inorganic photoreceptor may be, for example, amorphous silicon or selenium. Examples of the organic photoreceptor include a multilayer photoreceptor having a laminated structure in which a layer (charge generation layer) in which a charge generation material such as metal-free phthalocyanine or titanyl phthalocyanine is dispersed in a binder resin and a layer (charge transport layer) in which a charge transport material is dispersed in a binder resin are stacked on a support such as an aluminum drum, and a single-layer photoreceptor having a single-layer photosensitive layer on a support in which both a charge generation material and a charge transport material are dispersed in a binder resin. In the single-layer photoreceptor, a hole transport agent and an electron transport agent can be added to the photosensitive layer as charge transport materials. An undercoat layer may also be provided between the support and the multilayer charge generation layer or the single-layer photosensitive layer.

[0109] The shape of the electrostatic latent image carrier is not particularly limited and can be appropriately selected depending on the purpose, but is preferably cylindrical. The outer diameter of the cylindrical electrostatic latent image carrier is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 3 mm to 100 mm, more preferably 5 mm to 50 mm, and even more preferably 10 mm to 30 mm.

[0110] <Electrostatic latent image forming unit and electrostatic latent image forming process> The electrostatic latent image forming unit in the image forming apparatus according to the present invention is not particularly limited as long as it is a means for forming an electrostatic latent image on an electrostatic latent image carrier, and can be appropriately selected depending on the purpose. The electrostatic latent image forming unit includes, for example, a charging device (charger) that uniformly charges the surface of the electrostatic latent image carrier, and an exposure device (exposure device) that imagewise exposes the surface of the electrostatic latent image carrier. The electrostatic latent image forming step in the image forming method of the present invention is a step of forming an electrostatic latent image on an electrostatic latent image carrier, and includes a charging step of charging the surface of the electrostatic latent image carrier, and an exposure step of exposing the charged surface of the electrostatic latent image carrier to light to form an electrostatic latent image. Charging can be carried out, for example, by applying a voltage to the surface of the electrostatic latent image bearing member using a charging device (charger). The exposure can be carried out, for example, by exposing the surface of the electrostatic latent image bearing member to light in an imagewise manner using an exposure device (exposure unit). The formation of an electrostatic latent image can be carried out, for example, by uniformly charging the surface of the electrostatic latent image bearing member and then exposing it to light in an imagewise manner, and can be carried out by an electrostatic latent image forming unit.

[0111] -Charging device (charger)- The charger is not particularly limited and can be appropriately selected depending on the purpose. Examples thereof include a contact charger equipped with a conductive or semiconductive roll, brush, film, rubber blade, etc., and a non-contact charger utilizing corona discharge such as a corotron or scorotron.

[0112] The shape of the charger may be any shape such as a roller, a magnetic brush, a fur brush, etc., and can be selected according to the specifications and shape of the image forming apparatus.

[0113] The charger is preferably one that is arranged in contact or non-contact with the electrostatic latent image carrier and charges the surface of the electrostatic latent image carrier by applying a superimposed DC and AC voltage to it, or one that is a charging roller that is arranged in close proximity to the electrostatic latent image carrier but not in contact with it via a gap tape and charges the surface of the electrostatic latent image carrier by applying a superimposed DC and AC voltage to the charging roller.

[0114] The charger is not limited to a contact type charger, but it is preferable to use a contact type charger since it allows for an image forming apparatus in which the amount of ozone generated from the charger is reduced.

[0115] -Exposure device (exposure equipment)- The exposing device is not particularly limited as long as it can expose the surface of the electrostatic latent image carrier charged by the charger in the form of an image to be formed, and can be appropriately selected depending on the purpose. Examples of the exposing device include various exposing devices such as a copying optical system, a rod lens array system, a laser optical system, and a liquid crystal shutter optical system.

[0116] The light source used in the exposure device is not particularly limited and can be appropriately selected depending on the purpose. Examples include general light-emitting materials such as fluorescent lamps, tungsten lamps, halogen lamps, mercury lamps, sodium lamps, light-emitting diodes (LEDs), semiconductor lasers (LDs), and electroluminescence (EL). In order to irradiate only light in a desired wavelength range, various filters such as a sharp cut filter, a band pass filter, a near infrared cut filter, a dichroic filter, an interference filter, and a color temperature conversion filter can be used. It is also possible to employ a backlight system in which exposure is performed imagewise from the back side of the electrostatic latent image carrier.

[0117] <Developing section and developing process> The developing unit in the image forming apparatus according to the present invention is not particularly limited as long as it can develop the electrostatic latent image formed on the electrostatic latent image carrier to form a toner image, and can be appropriately selected depending on the purpose. For example, the developing unit can be suitably equipped with a developing device that stores toner and can apply the toner to the electrostatic latent image in a contact or non-contact manner, and a developing device equipped with a toner container is preferred. The developing step in the image forming method of the present invention is a step of forming a toner image by sequentially developing an electrostatic latent image with toners of multiple colors. The toner image can be formed, for example, by developing the electrostatic latent image with the toners, using a developing device.

[0118] In the developing unit and the developing step, the toner according to an embodiment is used. Preferably, a toner image may be formed by using a developer containing the toner according to an embodiment and, if necessary, other components such as a carrier.

[0119] The developing device may be a single-color developing device or a multi-color developing device, and is preferably a developing device having, for example, an agitator that charges the toner by friction agitation, a magnetic field generating unit fixed inside, and a rotatable developer carrier that carries developer containing toner on its surface.

[0120] In the developing unit, for example, toner and carrier are mixed and stirred, and the friction caused by this causes the toner to become charged and be held in a standing state on the surface of the rotating magnet roller, forming a magnetic brush. Because the magnet roller is located near an electrostatic latent image carrier (photosensitive member), some of the toner constituting the magnetic brush formed on the surface of the magnet roller moves to the surface of the electrostatic latent image carrier (photosensitive member) by electrical attraction. As a result, the electrostatic latent image is developed with the toner, and a toner image made of the toner is formed on the surface of the electrostatic latent image carrier (photosensitive member).

[0121] The image forming apparatus according to the present invention may include a total of five developing units, including developing units for color toners (black, cyan, magenta, and yellow) and a developing unit for the toner of the present invention. The toner of the present invention may be of any color, but is preferably colorless or white. The developing units may use the toner according to one embodiment as some or all of the black, cyan, magenta, and yellow color toners.

[0122] The development method may be a premix development method, in which a premix developer in which toner and carrier are mixed in advance is replenished. In the premix development method, the excess carrier in the developing device is discharged as excess developer. This gradually refreshes the developer in the developing device. This can extend the replacement cycle due to developer deterioration and eliminate the effort required for developer replacement.

[0123] <Transfer section and transfer process> The transfer section in the image forming apparatus according to the present invention preferably has a first transfer section that transfers a toner image onto an intermediate transfer body to form a composite transfer image, and a second transfer section that transfers the composite transfer image onto a recording medium. The intermediate transfer body is not particularly limited and can be appropriately selected from known transfer bodies depending on the purpose, and a transfer belt is a suitable example.

[0124] The transfer step in the image forming apparatus of the present invention is a step of transferring a toner image onto a recording medium. The transfer step preferably uses an intermediate transfer member, and after the toner image is primarily transferred onto the intermediate transfer member, the toner image is secondarily transferred onto the recording medium.

[0125] It is more preferable that the transfer step includes a first transfer step in which toner of two or more colors, preferably full-color toner, is used to transfer a toner image onto an intermediate transfer body to form a composite transfer image, and a second transfer step in which the composite transfer image is transferred onto a recording medium. The transfer can be carried out, for example, by charging the toner image onto an electrostatic latent image carrier (photosensitive member) using a transfer charger, and can be carried out in the transfer section.

[0126] The transfer unit (first transfer unit and second transfer unit) preferably has at least a transfer device that peels and charges the toner image formed on the electrostatic latent image carrier (photosensitive member) onto the recording medium. The number of the transfer units may be one or more.

[0127] Examples of the transfer device include a corona transfer device using corona discharge, a transfer belt, a transfer roller, a pressure transfer roller, and an adhesive transfer device.

[0128] The recording medium is typically plain paper, but is not particularly limited as long as it is capable of transferring the unfixed image after development, and can be selected appropriately depending on the purpose. Release paper, a PET base for an OHP, etc. can also be used.

[0129] <Fixing unit and fixing process> The fixing unit in the image forming apparatus according to the present invention is not particularly limited and can be appropriately selected depending on the purpose, but a known heating and pressurizing unit is suitable. Examples of the heating and pressurizing unit include a combination of a heating roller and a pressure roller, and a combination of a heating roller, a pressure roller, and an endless belt. The fixing process in the image forming apparatus of the present invention is a process of fixing a toner image transferred to a recording medium using a fixing device, and may be performed for each color developer each time it is transferred to a recording medium, or may be performed simultaneously for each color developer in a stacked state.

[0130] The fixing section is preferably a heating and pressurizing section that has a heating element having a heat generating element, paper or release paper that contacts the heating element, and a pressure member that presses against the heating element via the paper or release paper, and that can heat and fix a recording medium on which an unfixed image has been formed by passing it between the film and the pressure member. The heating temperature in the heating and pressurizing section is usually preferably 80°C to 200°C. The surface pressure in the heating and pressing section is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 10 N / cm 2 More than 80N / cm 2 It is preferable that:

[0131] In this embodiment, depending on the purpose, for example, a known optical fixing device may be used together with or instead of the fixing unit.

[0132] <Other departments and other processes> In addition to the above-described configuration, the image forming apparatus according to the present invention may include other units appropriately selected as required, such as a static eliminating unit, a cleaning unit, a recycling unit, and a control unit. In addition to the above-described configuration, the image forming method of the present invention may include other steps appropriately selected as necessary, such as a charge eliminating step, a cleaning step, and a recycling step.

[0133] <<Static elimination unit and static elimination process>> The charge removal unit is not particularly limited as long as it can apply a charge removal bias to the electrostatic latent image carrier, and can be appropriately selected from known charge removal devices, and a suitable example is a charge removal lamp. The charge removal step is a step of removing electricity by applying a charge removal bias to the electrostatic latent image bearing member, and can be suitably performed by the charge removal unit.

[0134] <<Cleaning department and cleaning process>> The cleaning unit is not particularly limited as long as it can remove toner remaining on the electrostatic latent image carrier, and can be appropriately selected from known cleaners, such as magnetic brush cleaners, electrostatic brush cleaners, magnetic roller cleaners, blade cleaners, brush cleaners, and web cleaners. The cleaning step is a step of removing the toner remaining on the electrostatic latent image carrier, and can be suitably performed by the cleaning unit.

[0135] The image forming apparatus according to the present invention can improve cleaning performance by including the cleaning unit. Specifically, by controlling the inter-toner adhesion, the fluidity of the toner can be controlled, improving cleaning performance. Furthermore, by controlling the properties of the deteriorated toner, excellent cleaning quality can be maintained even under severe conditions such as extended life and high temperature and humidity. Furthermore, since the external additives can be sufficiently liberated from the toner on the photoreceptor, a deposition layer (dam layer) of the external additives can be formed in the cleaning blade nip, thereby achieving high cleaning performance.

[0136] <<Recycling Department and Recycling Process>> The recycling section is not particularly limited, and examples thereof include known conveying means. The recycling step is a step of recycling the toner removed in the cleaning step into the developing unit, and can be suitably carried out by the recycling unit.

[0137] <<Control Unit>> The control unit can control the movement of each of the above-mentioned units. The control unit is not particularly limited as long as it can control the movement of each of the above-mentioned units, and can be appropriately selected depending on the purpose. Examples of the control unit include control devices such as a sequencer and a computer.

[0138] The image forming apparatus according to one embodiment can form images using the toner according to one embodiment, and therefore has excellent adhesion to fabric, can reduce power consumption, and can stably provide high-quality images.

[0139] Here, one aspect of an image forming apparatus according to an embodiment will be described with reference to Fig. 3. However, the applications of the present invention are not limited to these embodiments. In each drawing, the same components are denoted by the same reference numerals, and redundant explanations may be omitted. Furthermore, the number, position, shape, etc. of the following components are not limited to this embodiment, and may be any number, position, shape, etc. that is preferable for implementing the present invention.

[0140] FIG. 3 is a schematic diagram illustrating an example of an image forming apparatus according to an embodiment. 3 is a so-called tandem image forming apparatus in which four toner image forming units 20Y, 20C, 20M, and 20K for yellow, cyan, magenta, and black are arranged in parallel, and toner images of each color, yellow (Y), cyan (C), magenta (M), and black (K), formed by each toner image forming unit are superimposed to form a full-color image. Note that there are no particular restrictions on the arrangement of the toner image forming units for each color.

[0141] Each toner image forming unit 20Y, 20C, 20M, and 20K includes a photosensitive drum 4Y, 4C, 4M, and 4K that is rotated and driven as an image carrier. Also, an exposure device 45 is provided to expose each of the photosensitive drums 4Y, 4C, 4M, and 4K to laser light or LED light based on image information of each color to form a latent image.

[0142] An intermediate transfer belt 60 serving as an intermediate transfer body is disposed so as to be movable on its surface, facing each of the toner image forming units 20Y, 20C, 20M, and 20K. Primary transfer rollers 61Y, 61C, 61M, and 61K are disposed at positions facing the photosensitive drums 4Y, 4C, 4M, and 4K across the intermediate transfer belt 60, and transfer the toner images of each color formed on the photosensitive drums 4Y, 4C, 4M, and 4K onto the intermediate transfer belt 60.

[0143] Primary transfer rollers 61Y, 61C, 61M, and 61K sequentially transfer the respective color toner images formed by the respective toner image forming units 20Y, 20C, 20M, and 20K, which will be described later, onto the intermediate transfer belt 60, and form a full-color image by superimposing the images.

[0144] A paper feed unit 70 consisting of a paper feed cassette 71, paper feed rollers 72, etc. is provided at the bottom of the image forming apparatus, and sends out transfer paper toward registration rollers 73. The registration rollers 73 send out transfer paper toward the opposing portion of the intermediate transfer belt 60 and secondary transfer device 65 in accordance with the timing of the toner image formation. The full-color toner image on the intermediate transfer belt 60 is transferred onto the transfer paper by the secondary transfer device 65, fixed by the fixing device 90, and then discharged outside the apparatus.

[0145] Next, we will explain each of the toner image forming units 20Y, 20C, 20M, and 20K. Since each of the toner image forming units 20Y, 20C, 20M, and 20K has almost the same configuration and operation except for the color of the toner they contain, in the following explanation, the suffixes Y, C, M, and K used to distinguish between the colors will be omitted and only the configuration and operation of the toner image forming unit 20 will be explained.

[0146] 4 is a schematic diagram illustrating the configuration of the main components of an embodiment of an image forming apparatus. Various devices for performing electrophotographic processes, such as a charging device 40, a developing device 50, and a cleaning device 30, are arranged around the photosensitive drum 4 of the toner image forming unit 20, and form toner images of various colors on the photosensitive drum 4 through known operations. Such toner image forming unit 20 may be an integrally formed process cartridge that is detachable from the main body of the image forming apparatus.

[0147] 5 is a schematic diagram showing the main configuration of another example of an image forming apparatus equipped with five developing units. Note that a description of the same points as those in the image forming apparatus described above will be omitted.

[0148] The imaging device of this embodiment includes photosensitive bodies (photosensitive body 5, photosensitive body 11, photosensitive body 17, photosensitive body 23, photosensitive body 29), and around the photosensitive bodies, there are provided chargers (charger 6, charger 12, charger 18, charger 24, charger 30), developing means (developing means 8, developing means 14, developing means 20, developing means 26, developing means 32), transfer devices (transfer device 10, transfer device 16, transfer device 22, transfer device 28, transfer device 34), cleaning devices (cleaning device 9, cleaning device 15, cleaning device 21, cleaning device 27, cleaning device 33), and intermediate transfer belt cleaning device 42, and exposure light (exposure light 7, exposure light 13, exposure light 19, exposure light 25, exposure light 31) is irradiated onto the photosensitive bodies. Furthermore, the intermediate transfer belt cleaning device 42 may be provided with a collecting means for receiving the removed toner, etc. A dish-shaped tray or the like can be used as the collecting means.

[0149] The developing units for each color include the photoconductor, the charger, the developing means, the cleaning device, etc. Developing unit 35 uses white or transparent toner, developing unit 36 ​​uses black toner, developing unit 37 uses cyan toner, developing unit 38 uses magenta toner, and developing unit 39 uses yellow toner to form images, which are then transferred to intermediate transfer belt 40 and further formed. The image formed on intermediate transfer belt 40 is transferred to a recording medium by transfer device 41 and fixed by fixing device 43. Below the developing units, paper feed cassette 1 and paper feed roller 2 are provided, which feed transfer paper toward registration rollers 3 and 4. The registration rollers 3 and 4 feed transfer paper toward the opposing portion of intermediate transfer belt 40 and transfer device 41 in accordance with the timing of the toner image formation.

[0150] In this embodiment, an elastic intermediate transfer belt can also be used as the intermediate transfer belt 40. As the elastic intermediate transfer belt, for example, one in which a flexible elastic layer is laminated on a rigid base layer that can provide relatively flexibility can be used. In order to prevent the intermediate transfer belt 40 from meandering, a guide member for preventing the intermediate transfer belt 40 from shifting may be provided on the inner peripheral surface of the intermediate transfer belt 40 . [Example]

[0151] The present invention will be described in more detail below based on examples, but the technical scope of the present invention is not limited to the following examples in any way. In the following description, unless otherwise specified, "parts" means "parts by mass" and "%" means "% by mass".

[0152] <Preparation of antiviral agents> Antiviral agent A: 45.0 parts of commercially available copper(I) iodide powder (manufactured by Wako Pure Chemical Industries, Ltd.) as CuI microparticles, 1.0 part of a surfactant, and 54.0 parts of zirconium oxide particles (manufactured by Nippon Denko Co., Ltd.) as inorganic compound microparticles were pre-dispersed in 800.0 parts of methanol, and then crushed and dispersed in a bead mill to obtain a slurry of copper iodide (CuI) particles coated with or supporting zirconium oxide. The average primary particle diameter of this mixture was 120 nm. This was dried to obtain a mixed powder of antiviral agent A. As the powder has a certain degree of cohesiveness, the dispersed particle size in the toner is defined as the particle size including the aggregates.

[0153] Antiviral agents B and C: A mixed powder of antiviral agents B and C was prepared in the same manner as for preparation of antiviral agent A, except that the amounts of copper iodide and zirconium oxide used in preparation of antiviral agent A were changed. Furthermore, antiviral agents D and E were obtained in the same manner as in the preparation of antiviral agent A, except that tin oxide and aluminum oxide were used as the inorganic dispersant. Furthermore, Zeomic Type AJ (manufactured by Sinanen Zeomic Co., Ltd.) was used as Ag-based antibacterial material F. The compositions of antiviral agents A to E are shown in Table 2 below. The values ​​in the table are in parts.

[0154] [Table 2]

[0155] <Preparation of antiviral toner masterbatch 1> 30 parts of polymer dispersant, 27 parts of polyethylene resin, and 3 parts of polyethylene glycol were prepared, dissolved and mixed in a toluene solvent, and dispersed using a ball mill. After that, 40% of the above-mentioned slurry of antiviral material C was added in a solid content ratio (400 parts of slurry, 40 parts solids), and the mixture was further dispersed and dried to obtain antiviral toner [Masterbatch 1]. This [Masterbatch 1] was used in Comparative Example 4 described below.

[0156] Example 1 <Toner Production> 45 parts of polyester resin 1 (RN-306SF, manufactured by Kao Corporation) as a binder resin, 50 parts of polyester resin 2 (RN-290, manufactured by Kao Corporation), 5 parts of ester wax (WEP-5, manufactured by NOF Corporation) as a release agent, and 8 parts of antiviral agent A as an antiviral agent were premixed using a Henschel mixer (FM20B, manufactured by Nippon Coke and Engineering Co., Ltd.), and then melted and kneaded in a single-screw kneader (Buss co-kneader "MDK46-11D", manufactured by Buss) at a raw material supply rate to the barrel of 16 kg / h, a screw temperature of 40°C, and a kneading temperature of 100°C to 130°C (zone barrel temperature: Z1 zone 130°C, Z2 and Z3 zones 100°C) to obtain a kneaded product. The resulting kneaded material was cooled to room temperature and then coarsely pulverized to 200-300 μm using a Rotoplex. Next, a counter jet mill (100AFG, manufactured by Hosokawa Micron Corporation) was used to finely pulverize the material to a mass average particle size of (6.5±0.3) μm while appropriately adjusting the pulverization air pressure. The finely pulverized material was then classified using an air classifier (EJ-LABO, manufactured by Matsubo Corporation) while appropriately adjusting the louver opening to obtain a number average particle size: Dp50 of (7.0±0.3) μm, thereby obtaining toner base particles.

[0157] Next, 0.8 parts of HDK-2000 (registered trademark) (manufactured by Clariant Co., Ltd.), 0.5 parts of H05TD (registered trademark) (manufactured by Clariant Co., Ltd.), and 0.3 parts of MT-150IB (registered trademark) (manufactured by Teika Co., Ltd.) were added to 100 parts of the toner base particles, and the mixture was stirred and mixed using a Henschel mixer. This produced [Toner 1]. The toner particle diameter Dp50 at this time was 7.1 μm.

[0158] 3 g of the obtained [Toner 1] was weighed and pressed in a molding machine to produce 3 cm diameter pellets, which were then measured using qualitative fluorescent X-ray analysis in EZ mode. The intensities of Cu and Zr obtained were 912 kcps and 2172 kcps, respectively. The average dispersed particle size of the antiviral agent was 251 nm.

[0159] (Examples 2 to 7 and Comparative Examples 1 to 6) In Examples 2 to 7, [Toner 2] to [Toner 13] were obtained in the same manner as in Example 1, except that the toner raw materials in Example 1 were changed to the combinations shown in Tables 3-1 and 3-2 below. The compositions of Toners 1 to 13 are shown in Tables 3-1 and 3-2. Table 4 shows the fluorescent X-ray intensity of each toner.

[0160] [Table 3-1] [Table 3-2]

[0161] The materials used in the compositions shown in Tables 3-1 and 3-2 are as follows: <Binder resin> Polyester resin 1 (RN-306SF, manufactured by Kao Corporation, low acid value resin, acid value: 8 mg KOH / g) Polyester resin 2 (RN-290, manufactured by Kao Corporation, high acid value resin, acid value: 27 mg KOH / g) <Release agent> Wax (ester wax: WEP-5, manufactured by Nippon Oil & Fats Co., Ltd.) <Charge control agent> CCA (zirconium salicylate: TN-105, manufactured by Hodogaya Chemical Co., Ltd.)

[0162] <Preparation of two-component developer> [Creating the carrier] A mixture of the following carrier raw materials was dispersed in a homomixer for 20 minutes to prepare a coating layer forming solution. This coating layer forming solution was applied to a core material using Mn ferrite particles with a mass average particle size of 40 μm, with the temperature in the fluidized bed coating device controlled to 70°C, so that the average film thickness on the core material surface was 0.20 μm, and then dried. The resulting carrier was fired in an electric furnace at 180°C for 2 hours to obtain Carrier A. (carrier raw materials) Silicone resin (organo straight silicone): 100 parts Toluene: 100 parts γ-(2-aminoethyl)aminopropyltrimethoxysilane: 5 parts Carbon black: 10 parts

[0163] [Preparation of two-component developer] Each of the toners prepared in Examples 1 to 7 and Comparative Examples 1 to 6 was mixed uniformly with Carrier A for 5 minutes at 48 rpm using a Turbler mixer (manufactured by Willy & Bachofen (WAB)) and charged to prepare a two-component developer. The mixing ratio of the toner and Carrier A was adjusted to the toner concentration (7% by mass) of the initial developer for the evaluation machine, and the developers were obtained. Table 4 shows the evaluation results obtained using the developers containing the toners prepared in Examples 1 to 7 and Comparative Examples 1 to 6.

[0164] [Table 4]

[0165] [Evaluation method] Using the obtained two-component developer, development was carried out in a modified copier (imagioMF7070, manufactured by Ricoh Co., Ltd.), and the images were continuously printed in an MM environment (temperature: 23°C, humidity: 50%RH) at 5,000 sheets / day, initially and after a 30,000-sheet (30,000-sheet) run, using A4-size paper (brand: RICOH MyPaper, manufactured by Ricoh Co., Ltd.) in 40% print mode, in landscape orientation, with white solid images and black solid images. The obtained samples were evaluated for toner quality by the following methods.

[0166] <Antiviral> Using the obtained two-component developer, development was carried out in a modified copier (imagioMF7070, manufactured by Ricoh Co., Ltd.), and a black solid image was printed on an OHP sheet in an MM environment (temperature: 23°C, humidity: 50% RH) to form a fixed image, which was then cut into multiple 5 cm squares to create samples for antiviral testing. The evaluation criteria are based on SIAA certification standards. Activity value: 2.0 or higher is considered effective and is OK. Antiviral testing was conducted in accordance with ISO 021702, using influenza virus tests on samples that had not undergone durability testing and samples that had undergone the light resistance test of the durability testing method. The evaluation results of antiviral activity are shown in Table 4. In this case, the SIAA certification criteria is that the antiviral activity value is 2.0 or higher.

[0167] (Evaluation criteria) ◎: Antiviral activity after both the light resistance test and durability test is 3.0 or higher, indicating sufficient effectiveness. SIAA certification is possible. 〇: Effective when the antiviral activity value after both the light resistance test and durability test is 2.0 or more and less than 3.0. SIAA certification is possible. ×: Antiviral activity value after treatment without durability test and with light resistance test If either or both of the above criteria are below 2.0, the product is ineffective and cannot obtain SIAA certification.

[0168] <Light resistance> Using a two-component developer, development was carried out in a modified copier (imagioMF7070, manufactured by Ricoh Co., Ltd.), and front printing was carried out on half-sized A4-size paper (brand: RICOH 180K paper, manufactured by Ricoh Co., Ltd.) in 40% print mode. The print was then cut into multiple 4 cm square pieces to prepare samples for lightfastness testing.

[0169] (Lightfastness test) The light resistance test in the present invention refers to the following. Test equipment: Non-weather meter (Ci4000) Irradiation conditions: 180W / m 2 Irradiation only mode (no water added) under acceleration conditions 0 hours: NEW (standard) 7h irradiation: Condition 1 Using a two-component developer, development was performed using a modified copy machine (imagioMF7070, manufactured by Ricoh Co., Ltd.), in a MM environment (temperature: 23°C, humidity: 50% RH), with an adhesion amount of 0.5 mg / cm on A4 size paper. 2 A half image of this was created, cut into 7cm x 7cm to 14cm pieces, and stored in a dark place. This was used as the 0-hour (reference) time. Samples were created under the irradiation conditions of Condition 1 and Condition 2 of the weather meter test, and X-Rite calculated ΔE = E (Condition 1) - E (NEW). Lightfastness was evaluated and judged as ΔE based on the following evaluation criteria.

[0170] [Evaluation criteria] ○: ΔE is 3 or less △: ΔE is greater than 3 and less than 5, so there is no problem in practical use ×: ΔE is greater than 5, and the color change is significant

[0171] <Confirmation of heat resistance and discoloration> 10g of toner was placed in a plastic container and left unopened at 40℃ and 70% humidity for two weeks. Next, the degree of toner aggregation is determined by passing it through a 200-mesh sieve to evaluate heat resistance. Discoloration due to moisture is also checked to see if there has been a significant change in the color of the toner. Discoloration to reddish-brown is particularly common. (Evaluation criteria) ○: Sieve residue: less than 1 mg and no discoloration △: Sieve residue: less than 1 mg and discoloration difference ×: Sieve residue: 1 mg or more

[0172] <Photoconductor scratches and image defects (streaks)> Scratches on the photoreceptor that have resulted in or are likely to result in image defects were evaluated using the following criteria based on the results of the observation of the photoreceptor surface with an optical microscope. For streak-like image defects, halftone images, solid white images, and solid black images were evaluated using a magnifying glass or optical microscope to look for image defects such as white streaks or defects in the photoreceptor cycles on the images, in the same manner as in the evaluation method for photoreceptor scratches described above, and the number of image defects on one sheet of A4 size paper was counted and evaluated using the following criteria.

[0173] [Evaluation criteria] ○: The photoreceptor surface is very good and there are no streak-like defects on the image. △: Lines are observed on the photoreceptor, but image defects of 10 mm or less in length and 0.5 mm or less in width are present in no more than three places on the image. Furthermore, there are no image defects exceeding 10 mm or 0.5 mm in width, so there is no problem in practical use. ×: When streaks and image defects are observed, there is a problem in practical use. If scratches or white or black deposits within 10mm in length and 0.5mm in width other than those mentioned above are observed in more than three places, or if scratches or toner deposits that are 10mm in length or more or exceed 0.5mm in width are observed, and streaks or image defects are observed on the image, there is a problem with practical use.

[0174] Although the embodiments have been described above, they are presented as examples and the present invention is not limited to the above embodiments. The above embodiments can be implemented in various other forms, and various combinations, omissions, substitutions, modifications, etc. can be made without departing from the spirit of the invention. These embodiments and their modifications are included within the scope and spirit of the invention, and are also included in the inventions and their equivalents as set forth in the claims.

[0175] The present invention includes, for example, the following aspects. (1) An antiviral toner comprising toner particles containing a binder resin and an antiviral agent, The antiviral agent contains particles composed of CuI and an inorganic dispersant containing Zr, The specific gravity of the inorganic dispersant is within ±0.5 of the specific gravity of CuI, The binder resin is a polyester resin, the number average particle size of the antiviral agent dispersed in the polyester resin is 500 nm or less, In a fluorescent X-ray measurement of the toner particles, the X-ray intensity of Cu is 300 kcps or more, and the intensity ratio of the X-ray intensity of Zr to the X-ray intensity of Cu (Zr / Cu) is greater than 1.0. An antiviral toner characterized by: (2) The antiviral toner according to (1) above, wherein the inorganic dispersant is Zr oxide, the X-ray intensity of Cu is 400 kcps or more, and the intensity ratio of the X-ray intensity of Zr to the X-ray intensity of Cu (Zr / Cu) is 2.0 or more and 6.0 or less. (3) The antiviral toner according to (1) or (2) above, wherein 90% or more of the dispersed particle diameters of the antiviral agent in the antiviral toner are 300 nm or less, as determined by mapping using energy dispersive X-ray spectroscopy (EDX). (4) The antiviral toner according to any one of (1) to (3) above, wherein the antiviral toner is colorless, white, light brown, or gray. (5) The antiviral toner according to any one of (1) to (4) above, which has light resistance of ΔE≦5 in a light resistance test using an image printed at a coating amount of 0.5 mg / cm. (6) A toner storage unit containing the antiviral toner according to any one of (1) to (5) above. (7) The toner storage unit according to (6) above; an electrostatic latent image forming means for forming an electrostatic latent image on an electrostatic latent image carrier; a developing means for developing the electrostatic latent image with the toner to form a toner image; a transfer means for transferring the toner image onto a recording medium; and a fixing unit for fixing the transferred image transferred onto the recording medium. (8) an electrostatic latent image forming step of forming an electrostatic latent image on an electrostatic latent image carrier; a developing step of developing the electrostatic latent image with the toner according to any one of (1) to (5) above to form a toner image; a transfer step of transferring the toner image onto a recording medium; a fixing step of fixing the transferred image transferred onto the recording medium. [Explanation of symbols]

[0176] (Figures 3 and 4) 4 Photosensitive drum 20 Toner image forming unit 30 Cleaning device 40 Charging device 45 Exposure equipment 50 Developing device 60 Intermediate transfer belt 61 Primary transfer roller 65 Secondary transfer device 66 Belt cleaning device 70 Paper feed section 71 Paper cassette 72 Paper feed roller 73 Registration roller 90 Fixing device

[0177] (Figure 5) 1 Paper feed section 5, 11, 17, 23, 29 Photoreceptor 6, 12, 18, 24, 30 Charger 7, 13, 19, 25, 31 Exposure light 8, 14, 20, 26, 32 Developing means 9, 15, 21, 27, 33 Cleaning device 10, 16, 22, 28, 34 Transcription device 35 White toner development unit 36 Black toner developing unit 37 Cyan toner development unit 38 Magenta toner developing unit 39 Yellow toner developing unit 40 Intermediate transfer belt 41 Transcription device 42 Intermediate transfer belt cleaning device 43 Fixing device [Prior art documents] [Patent documents]

[0178] [Patent Document 1] Patent No. 7376355 [Patent Document 2] Japanese Patent Publication No. 2023-110535< / cui>

Claims

1. An antiviral toner comprising toner particles containing a binder resin and an antiviral agent, The antiviral agent contains particles composed of CuI and an inorganic dispersant containing Zr, The specific gravity of the inorganic dispersant is within ±0.5 of the specific gravity of CuI, The binder resin is a polyester resin, the number average particle size of the antiviral agent dispersed in the polyester resin is 500 nm or less, In a fluorescent X-ray measurement of the toner particles, the X-ray intensity of Cu is 300 kcps or more, and the intensity ratio of the X-ray intensity of Zr to the X-ray intensity of Cu (Zr / Cu) is greater than 1.

0. An antiviral toner characterized by:

2. 2. The anti-viral toner according to claim 1, wherein the inorganic dispersant is a Zr oxide, the X-ray intensity of Cu is 400 kcps or more, and the intensity ratio of the X-ray intensity of Zr to the X-ray intensity of Cu (Zr / Cu) is 2.0 or more and 6.0 or less.

3. 3. The antiviral toner according to claim 1, wherein 90% or more of the dispersed particle diameters of the antiviral agent in the antiviral toner are 300 nm or less, as determined by mapping using energy dispersive X-ray spectroscopy (EDX).

4. 3. The anti-viral toner according to claim 1, wherein the anti-viral toner is colorless, white, light brown, or gray.

5. 3. The anti-viral toner according to claim 1, wherein the light resistance is ΔE≦5 in a light resistance test using an image printed at a coating amount of 0.5 mg / cm.

6. A toner storage unit containing the antiviral toner according to claim 1 or 2.

7. The toner storage unit according to claim 6, an electrostatic latent image forming means for forming an electrostatic latent image on an electrostatic latent image carrier; a developing means for developing the electrostatic latent image with the toner to form a toner image; a transfer means for transferring the toner image onto a recording medium; and a fixing unit for fixing the transferred image transferred onto the recording medium.

8. an electrostatic latent image forming step of forming an electrostatic latent image on an electrostatic latent image carrier; a developing step of developing the electrostatic latent image with the toner according to claim 1 or 2 to form a toner image; a transfer step of transferring the toner image onto a recording medium; a fixing step of fixing the transferred image transferred onto the recording medium.

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