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

Abstract

The invention relates to a toner, a toner storage unit, an image forming apparatus, and an image forming method. The purpose of the present invention is to provide a highly safe antiviral toner capable of stably forming an image having antiviral properties. An antiviral toner according to the present invention includes toner particles containing a binder resin and an antiviral agent, the antiviral agent containing particles comprising CuI and an inorganic dispersant containing Zr, the specific gravity of the inorganic dispersant being within the range of + / -0.5 of the specific gravity of CuI, the binder resin being a polyester resin, and the inorganic dispersant being an inorganic dispersant having a specific gravity of Zr within the range of + / -0.5 of the specific gravity of CuI. The number average particle diameter of the antiviral agent dispersed in the polyester resin is 500 nm or less, 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 in an X-ray fluorescence measurement of the toner particles.

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 Art

[0002] In an electrophotographic method in which an electrostatic latent image is developed by 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 by a developer containing a toner to form a toner image, the toner image is transferred to a transfer material such as paper, and then fixed by heat and pressure to form a fixed image.

[0003] As described above, the method of fixing images by heat is suitable, for example, in the recent situation where there are concerns about viral infections such as coronavirus or influenza virus, and can be easily and safely applied to situations where wallpaper or sheets, printed materials in hospitals, or packaging materials are touched by hands.

[0004] Patent Document 1 describes a resin composition containing an antibacterial / antiviral agent composed of monovalent copper compound fine particles coated with an inorganic compound dispersant.

[0005] Patent Document 2 describes an antibacterial and antiviral toner containing a silver-based antibacterial material and a pigment.

[0006] [Patent Document] [Patent Document 1] Japanese Patent No. 7376355

[0007] [Patent Document 2] Japanese Patent Application Laid-Open No. 2023-110535 Summary of the Invention

[0008] The technology described in Patent Document 1 involves mixing first and second masterbatch particles to produce a resin composition. The first masterbatch particles are resin particles containing an antibacterial / antiviral agent, while the second masterbatch particles are a mixture of a hydrophilic compound and a base resin particle at a predetermined weight ratio. This is unrelated to the toner. Furthermore, the technology described in Patent Document 2 uses a silver-based antibacterial agent and a pigment in combination.

[0009] An object of the present invention is to provide a highly safe antiviral toner capable of stably forming an image having antiviral properties.

[0010] As a means for solving the above-mentioned problems, the toner according to the present invention is as follows:

[0011] An antiviral toner comprising toner particles, wherein the toner particles contain a binder resin and an antiviral agent, wherein:

[0012] The antiviral agent contains particles composed of CuI and an inorganic dispersant containing Zr,

[0013] The specific gravity of the inorganic dispersant is within the range of ±0.5 of the specific gravity of CuI,

[0014] The bonding resin is a polyester resin,

[0015] The number average particle size of the antiviral agent dispersed in the polyester resin is 500 nm or less,

[0016] In fluorescent X-ray measurement of the toner particles, the Cu X-ray intensity is 300 kcps or more, and the intensity ratio of the Zr X-ray intensity to the Cu X-ray intensity (Zr / Cu) is greater than 1.0.

[0017] The effect of the present invention is described below:

[0018] According to the present invention, a highly safe antiviral toner capable of stably forming an image having antiviral properties can be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is an EDX mapping image of the Cu element of the toner particles.

[0020] Figure 2A This is a mapping image of the Cu element in a toner without using a masterbatch. Figure 2B This is a mapping image of the Cu element in a toner using a masterbatch.

[0021] Figure 3 This is a schematic diagram showing an example of an image forming apparatus according to an embodiment of the present invention.

[0022] Figure 4 This is a schematic diagram for explaining the configuration of a main part of an embodiment of an image forming apparatus.

[0023] Figure 5 This is a schematic diagram of the main structure of another example of an image forming apparatus having five developing mechanisms.

[0024] The symbols in the figure are explained as follows:

[0025] ( Figure 3 and Figure 4 )

[0026] 4 Photoreceptor drum

[0027] 20 Toner image forming section

[0028] 30 Cleaning device

[0029] 40 Charging device

[0030] 45 Exposure device

[0031] 50 Development device

[0032] 60 Intermediate transfer belt

[0033] 61 Primary transfer roller

[0034] 65 Secondary transfer device

[0035] 66 with cleaning device

[0036] 70 Paper feeding unit

[0037] 71 Paper feed box

[0038] 72 Paper feed roller

[0039] 73 positioning roller

[0040] 90 Fixing unit

[0041] ( Figure 5 )

[0042] 1 Paper feed unit

[0043] 5, 11, 17, 23, 29 Photoreceptors

[0044] 6, 12, 18, 24, 30 chargers

[0045] 7, 13, 19, 25, 31 exposure light

[0046] 8, 14, 20, 26, 32 development mechanism

[0047] 9, 15, 21, 27, 33 cleaning devices

[0048] 10, 16, 22, 28, 34 transfer units

[0049] 35 White toner developer unit

[0050] 36 Black toner developer unit

[0051] 37 Cyan toner developer unit

[0052] 38 Magenta toner developer unit

[0053] 39 Yellow toner developer unit

[0054] 40 Intermediate transfer belt

[0055] 41 Transfer device

[0056] 42 Intermediate transfer belt cleaning device

[0057] 43 Fixing device DETAILED DESCRIPTION

[0058] Hereinafter, embodiments of the present invention will be described in detail. The embodiments are not limited to the following descriptions and can be appropriately changed without departing from the gist of the present invention. In addition, the "to" indicating a numerical range in this specification, unless otherwise specified, means that the numerical values recorded before and after the range are included as the lower limit and the upper limit.

[0059] (Toner)

[0060] The antiviral toner of the present invention comprises toner particles containing a binder resin and an antiviral agent containing particles of CuI and an inorganic dispersant containing Zr, and optionally contains a release agent, a charge control agent, and other components.

[0061] <Inorganic dispersants>

[0062] As the inorganic dispersant, the inorganic oxides shown in the following Table 1 can be cited as candidates.

[0063] Table 1

[0064]

[0065] From the viewpoint of uniform mixing with the antiviral material, the inorganic dispersant preferably has a specific gravity within the range of ±0.5 of the specific gravity of CuI.

[0066] From the viewpoint of coloring of the toner, the inorganic dispersant is more preferably colorless or white.

[0067] From the viewpoint of the storage stability of the toner, it is more preferable that the inorganic dispersant does not have excessively high water adsorption properties.

[0068] In view of the above, zirconium oxide is the most preferred inorganic dispersant.

[0069] From the perspective of antiviral function, the Cu X-ray intensity in fluorescent X-ray measurement of toner particles needs to be 300 kcps or higher. Furthermore, the Cu X-ray intensity is more preferably 400 kcps or higher, and even more preferably 600 kcps or higher.

[0070] Furthermore, the intensity ratio of the X-ray intensity of Zr to the X-ray intensity of Cu (Zr / Cu) needs to be greater than 1.0, more preferably 2.0 to 6.0, and even more preferably 2.0 to 5.0.

[0071] <CuI>

[0072] While there are many antimicrobial materials available worldwide, only a limited number offer both antiviral effectiveness and safety. Furthermore, antimicrobial and antiviral testing are regulated by the JIS, with certification and registration with the SIAA (Society for Antimicrobial Products Technology Association) serving as the general standard. Of these, antiviral performance is a more stringent certification requirement than antimicrobial performance.

[0073] Furthermore, no substance has been found that combines the antiviral effect and safety with the chargeability, light resistance, and heat-resistant storage properties of a toner.

[0074] The inventors conducted intensive research and found that by using a binder resin and a specific antiviral agent, they can be uniformly dispersed and introduced into the colorant, thereby achieving both high antiviral performance and the basic characteristics of the colorant, and simultaneously achieving light resistance and resistance to high-temperature and high-humidity storage.

[0075] There is a difference between the X-ray intensity of Cu and I as raw materials alone and when dispersed in a toner, depending on the dispersion state. 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.

[0076] Hereinafter, "X-ray intensity" may be referred to as "intensity".

[0077] Charge Control Agent

[0078] As the charge control agent (hereinafter referred to as CCA), any generally used one may be used, and colorless or white CCA is preferred as the color tone.

[0079] In addition, zirconium salicylate or the like can also be used as the metal-containing CCA.

[0080] When zirconium oxide is used as an inorganic dispersant for CuI, zirconium oxide and zirconium salicylate are present together. However, zirconium salicylate is dispersed separately from CuI in the toner and hardly acts as a dispersant for CuI. Therefore, their combined use presents no particular problem. However, when zirconium salicylate is used as a 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, to minimize the effect of significantly affecting the intensity ratio of the X-ray intensity of Zr to the X-ray intensity of Cu (Zr / Cu) from the zirconium-containing inorganic dispersant.

[0081] <Measurement Method of Fluorescent X-rays>

[0082] The method for measuring the X-ray intensity of metal elements such as Cu and Zr is not particularly limited and can be appropriately selected according to the purpose. In the present invention, the Cu and Zr intensities (kcps) of the above metal elements can be determined by the following apparatus and conditions.

[0083] First, 3.00 g of toner is formed into pellets with a diameter of 3 mm and a thickness of approximately 2 mm. If the specific gravity is quite high, convert the toner weight to a specific gravity and form the pellets into pellets approximately 2 mm thick to prepare the measurement sample. Before measurement, it is preferred to calibrate using a standard sample for metal measurement (manufactured by Rigaku Co., Ltd.), but proper management is not a problem. Qualitative analysis of the measurement sample is performed using a fluorescent X-ray analyzer, and the net intensity of the Cu-Kα radiation is calculated as the Cu intensity (kcps).

[0084] Zr and Al are also calculated in the same way.

[0085] ·Measurement device: ZSX Primus IV manufactured by Rigaku Co., Ltd.

[0086] X-ray tube: Rh

[0087] X-ray tube voltage: 50 kV

[0088] X-ray tube current: 10 mA

[0089] Measurement mode: EZ scan, sample type: polymer, measurement range: F~U

[0090] Measuring diameter: 30 mm, measuring time: standard.

[0091] The type of line is not particularly limited as long as it provides detection accuracy that allows for relative comparison. However, from the perspective of measurement accuracy and sensitivity, it is generally preferred to use the net intensity of Kα rays. The intensity values used in this invention are expressed as the net intensity of Kα rays for metal elements unique to the material.

[0092] The antiviral agent includes CuI particles and a dispersant as an antiviral material, and the dispersant coats the surface of the CuI particles or loads CuI particles on its surface to prevent the aggregation of CuI particles. As a dispersant, organic compounds such as polymer dispersants, surfactants, plasticizers, and inorganic compounds such as metal soaps can be suitably used, but in this embodiment, since it is possible to improve the contact with bacteria and viruses, it is easy to play an antibacterial and antiviral effect, it is preferred to use an inorganic compound. For example, the Zeta potential of inorganic compounds such as zirconium oxide, aluminum oxide, and titanium oxide has a positive potential at pH 7. In addition, viruses generally have a negative potential. Therefore, by coating copper compound particles with particles of these inorganic compounds, the contact between the antiviral agent and the virus can be improved, and therefore, it is easy to show an antiviral effect. Furthermore, by coating copper compound particles with inorganic compounds, copper compound particles are difficult to be oxidized, and therefore, antibacterial and antiviral effects can be sustained.

[0093] The number average particle size of the antiviral agent is not particularly limited and can be appropriately selected depending on the intended purpose. It is preferably between 10 nm and 500 nm, and more preferably between 10 nm and 300 nm. A number average particle size of 10 nm or greater prevents an increase in surface area, thereby minimizing deterioration in light resistance and discoloration of the toner. A number average particle size of 500 nm or less prevents insufficient antiviral properties due to a larger number average particle size, minimizing wear within the toner manufacturing apparatus and thus preventing manufacturability. Furthermore, the toner is free of metallic elements such as SUS, particularly Cr and Fe, which may discolor the toner itself, thereby preventing the toner from being incorporated into the toner.

[0094] However, in the present invention, the average dispersion diameter (including the aggregated state) of the antiviral agent is expressed as the number average particle diameter calculated by mapping of the Cu element in EDX.

[0095] When using a masterbatch resin that is incompatible with the binder resin and a masterbatch comprising CuI or a mixture of CuI and an inorganic dispersant according to the present invention, the masterbatch resin is dispersed in the toner so that island regions are formed within the sea-islands, with the CuI encapsulated within the masterbatch resin. In this case, an inorganic dispersant may be used, but using a small amount or no dispersant presents no particular problem.

[0096] In addition, when a masterbatch is formed using a resin compatible with the binder resin, the inorganic dispersant must be used in a certain amount or more. Therefore, the masterbatch may or may not be formed.

[0097] When using a resin incompatible with the binder resin, it is best to select a resin that is incompatible with the resin that serves as the main component of the anti-toner and forms a separate, discontinuous phase. This discontinuous phase of the resin incompatible with the binder resin is mixed with the resin that serves as the main component of the anti-viral toner, creating a phase-separated structure. This enhances the antibacterial and antiviral effects of the resin near the toner surface or the surface of the object being imaged.

[0098] In order to improve the diffusibility of viruses or bacteria, a resin having a certain degree of hydrophilicity is preferred.

[0099] Examples of resins incompatible with the binder resin contained in the antiviral toner include water-soluble synthetic polymers such as polyvinyl alcohol (PVA), polyvinyl pyrrolidone (PVP), polyethylene oxide (PEO), hydroxypropyl cellulose (HPC), polyethylene glycol (PEG), polyacrylamide (PAAM), polyacrylic acid (PAA), sodium polyacrylate, and polyethyleneimine; and acrylamide-acrylate copolymers such as 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 copolymers, ethylene-vinyl acetate copolymers, and dimethylacrylamide-glycidyl methacrylate copolymers.

[0100] By suppressing CuI release during pulverization while placing it within the toner and on the toner surface, CuI can be present on the toner surface and near the image surface during image formation. However, if only antibacterial properties are required, using an incompatible masterbatch resin is not a problem. However, if antiviral properties are desired, the dispersed domain structure is insufficient to protect against viruses, making it difficult to achieve sufficient antiviral properties.

[0101] Generally speaking, viruses are small, so the range within which antiviral materials can act on them—that is, the distance between the antiviral materials—is small, making it important to ensure this distance. Therefore, methods using a masterbatch made of a resin that is incompatible with the binder resin tend to result in insufficient antiviral performance.

[0102] Common surfactants can also be used as dispersants. However, when dispersed in a toner, the toner may discolor, for example, to a reddish-brown color when stored under high temperature and high humidity. This is fine as long as the color tone is not a problem. However, if color tone is a problem in colorless, white, or colored products, it is preferable to minimize the amount or omit the dispersant.

[0103] The dispersion state can be evaluated by EDX mapping of the toner using Cu or I. While the dispersion state can also be evaluated by mapping Zr in the dispersant, Zr is suitable for observing synchronization with Cu and I and dispersion in the toner. However, since Zr is dispersed uniformly in the toner to a level more consistent with Cu and I, Zr mapping is used to supplement the evaluation of the dispersion state of Cu and I.

[0104] Figure 1 This is a mapping image of the Cu element obtained by analyzing toner particles using EDX (Energy Dispersive X-ray Spectroscopy).

[0105] Zr is uniformly dispersed in the toner, and Cu and I exist in a state of small dispersed particle size in synchronization with Zr.

[0106] Furthermore, the dispersion state of CuI in the case of using a masterbatch and the case of not using a masterbatch can also be clearly determined by EDX.

[0107] FIG. 2 is an image obtained by analyzing toner particles through EDX. Figure 2A This is a mapping image of the Cu element in a toner without using a masterbatch. Figure 2B This is a mapping image of the Cu element in a toner using a masterbatch.

[0108] A method of measuring the number average particle size of the antiviral agent in the toner is described below.

[0109] <Measurement conditions>

[0110] The particle size distribution of the antiviral agent of the toner measured by a scanning electron microscope (SEM) and an energy dispersive X-ray analyzer (EDX) can be measured as follows.

[0111] A sample obtained by fixing a toner on a carbon ribbon and coating it with carbon to prevent charging was observed using a scanning electron microscope (SEM) and an energy dispersive X-ray analyzer (EDX).

[0112] Observation conditions: SU8230 SEM manufactured by Hitachi, Ltd. and EDXFlashFlat QUAD5060F manufactured by Bruker Corporation were used under the following conditions:

[0113] Accelerating voltage: 15 kV

[0114] Emission: 20 mV

[0115] Probe current: High

[0116] Condenser lens: 1.0

[0117] WD:11.2

[0118] Image magnification: arbitrarily select 2000 times, 5000 times or 10,000 times, and select several candidates for the target toner particles.

[0119] Next, the measurement position was determined at an image magnification of 20,000x. Under E(U) + SE(L), the toner surface was mapped in EDX HyperMap mode for at least 180 seconds. The position and size of the Cu element were determined while observing and comparing the toner SEM image, the Cu mapping image, and the composite image of the toner SEM image and the Cu mapping image. The positions and sizes of Al, Zn, and Sn were determined similarly.

[0120] However, Comparative Example 3 described later was calculated using an image mapped with the Zn element, Comparative Example 5 was calculated using an image mapped with the Al element, and Comparative Example 6 was calculated using an image mapped with the Sn element. All other examples used an image mapped with the Cu element.

[0121] Alternatively, the Cu-mapped EDX image may be binarized and the particle size calculated using other analysis software to determine the average particle size. In this case, the particle size is calculated based on at least 1,000 particles.

[0122] In this method, an EDX image mapped with Cu is selected, pasted onto an Excel sheet, and contrast is adjusted within Excel. Adjustments to the brightness and contrast of each image facilitate binarization. For example, target brightness settings of -15 to +30 and contrast settings of +10 to +40 are possible.

[0123] Copy the image using a sniping tool and save it as a JPEG file, resizing it to approximately 480 pixels x 360 pixels. Select at least 15 images, omitting images with dark shadows on the toner surface that are not suitable for binarization or images that are not completely covered by the toner surface.

[0124] When a binary region exists in a part other than particles due to element display or the like, the numerical value may be corrected by changing the image or excluding the region from calculation if the region is small and easy to calculate.

[0125] The contrast adjustment and binarization methods are not particularly limited. Here, the binarized processed image is calculated using image processing software Image-ProPlus 5.1J (manufactured by Media Cybernetics).

[0126] The settings and steps for binarization are as follows:

[0127] (1) Set Process > Enhance Contrast and specify Saturated pixels: 0.3%

[0128] (2) Binarization via Process → Binary → MakeBinary

[0129] (3) Adjust the size Image→Adjust→Size to 480×360 pixels ±5%, 8 bits (resize only when necessary).

[0130] (4) Use File → Save As → Jpeg to save the binary image.

[0131] These binarized images were subjected to image analysis processing using image analysis software: A-image-kun (manufactured by Asahi Kasei Engineering Corporation).

[0132] Transfer the binarized image obtained above to an image file. Select Particle Analysis in the Image Analysis tab to display the particle analysis parameters. Set "Equivalent Circle Diameter" for each parameter. Confirm the number of particles and equivalent circle diameter, and transfer the data to Excel.

[0133] Compare the calculated results (number of particles, equivalent circle diameter) in each of the above images with the analyzed images, delete images with obvious abnormalities or inappropriate image processing, set priorities, select the number of images, and make the number of analyzed particles greater than 1,000 based on the total number of images (Total number). Calculate the average value of the equivalent circle diameter as the number-average particle size of the antiviral agent.

[0134] <Binder resin>

[0135] The binder resin can be selected appropriately depending on the intended purpose, as long as its main component is a polyester resin. There is no particular problem even if a styrene, acrylic, or olefin-based resin is contained in a dispersant for other purposes such as a toner. However, the influence on CuI is preferably less than 10%. The acid value of the polyester resin is not particularly specified; for example, resins with low acid values below 10 mgKOH / g and resins with high acid values of 15 mgKOH / g or higher can be used.

[0136] The low-acid 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 intended purpose. Examples thereof include RN-306 (acid value: 7 mgKOH / g, manufactured by Kao Corporation) and RN-306 SF (acid value: 8 mgKOH / g, manufactured by Kao Corporation).

[0137] 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 intended purpose. Examples thereof include RN-290 (manufactured by Kao Corporation, 27 mgKOH / g).

[0138] The content of the low acid value resin is not particularly limited and may be appropriately selected depending on the intended 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.

[0139] The content of the high acid value resin is not particularly limited and may be appropriately selected depending on the intended 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.

[0140] The polyester resin is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include polyester resins obtained by polycondensation of alcohols and carboxylic acids.

[0141] The alcohol is not particularly limited and can be appropriately selected depending on the intended purpose. Examples thereof include glycols such as ethylene glycol, diethylene glycol, triethylene glycol, and propylene glycol; etherified bisphenols such as 1,4-bis(hydroxymethyl)cyclohexane and bisphenol A; other diol monomers; and trivalent or higher polyol monomers.

[0142] The carboxylic acid is not particularly limited and can be appropriately selected depending on the intended 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-dicarboxy-2-methylenecarboxypropane, and 1,2,7,8-octanetetracarboxylic acid.

[0143] The glass transition point (hereinafter also referred to as glass transition temperature) Tg of the polyester resin is not particularly limited and can be appropriately selected depending on the intended purpose, but is preferably 50°C to 75°C.

[0144] The method for measuring the glass transition point Tg is not particularly limited and may be appropriately selected depending on the intended purpose. For example, the method may be measured by DSC.

[0145] <Other adhesive resins)

[0146] The toner according to one embodiment may contain other binder resin components in addition to the above-mentioned polyester resin and polyolefin. Examples of other binder resins include styrene-based resins (including monomers or copolymers of styrene or styrene-substituted products) such as styrene, poly-α-styrene, styrene-chlorostyrene copolymers, styrene-propylene copolymers, styrene-butadiene copolymers, styrene-vinyl chloride copolymers, styrene-vinyl acetate copolymers, styrene-maleic acid copolymers, styrene-acrylate copolymers, styrene-methacrylate copolymers, styrene-α-methylchloroacrylate copolymers, and styrene-acrylonitrile-acrylate copolymers; epoxy resins, vinyl chloride resins, rosin-modified maleic acid resins, phenolic resins, polyethylene resins, polypropylene resins, petroleum resins, polyurethane resins, ketone resins, ethylene-ethyl acrylate copolymers, xylene resins, and polyvinyl butyral resins.

[0147] The method for producing the binder resin is not particularly limited, and a known production method such as bulk polymerization, solution polymerization, emulsion polymerization, or suspension polymerization can be used.

[0148] Release agent

[0149] The release agent is not particularly limited and can be appropriately selected depending on the intended 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 their metal salts; higher fatty acid amides; synthetic ester waxes; and various modified versions of the above waxes. 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.

[0150] The content of the release agent is not particularly limited and can be appropriately selected depending on the intended purpose. However, it is preferably 2% to 15% by mass, and more preferably 2.5% to 10% by mass, relative to the binder resin in the toner. A content of 2% to 15% by mass can prevent thermal offset, while a content of 15% to 15% by mass can prevent degradation of transferability and durability.

[0151] The melting point of the release agent is not particularly limited and can be appropriately selected depending on the intended purpose, but is preferably 60°C to 150°C, more preferably 65°C to 120°C. A melting point of 60°C or higher can prevent a decrease in the heat-resistant storage stability of the toner. A melting point of 150°C or lower can enhance the release properties.

[0152] Charge Control Agent

[0153] The charge control agent is not particularly limited and can be appropriately selected depending on the purpose. Examples thereof include modified products of aniline black and fatty acid metal salts, onium salts such as phosphonium salts and lake pigments thereof, triphenylmethane pigments and lake pigments thereof, metal salts of higher fatty acids, diorganotin oxides such as dibutyltin oxide, dioctyltin oxide, and dicyclohexyltin oxide, diorganotin boric acids such as dibutyltin borate, dioctyltin borate, and dicyclohexyltin borate, organometallic complexes, chelates, 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 their metal salts, acid anhydrides, esters, and phenol derivatives such as bisphenol.

[0154] The content of the charge control agent is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 0.1% by mass to 10% by mass, more preferably 1% by mass to 5% by mass, based on the binder resin of the toner.

[0155] <Other ingredients>

[0156] The other components are not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include colorants, external additives, flowability improvers, cleaning agents, and magnetic materials.

[0157] -Colorant-

[0158] The colorant is not particularly limited, and a colorant commonly used can be appropriately selected.

[0159] As the black toner, carbon black alone or a black toner having carbon black as a main component mixed with copper phthalocyanine or the like and adjusted in color tone and brightness is preferable.

[0160] As the cyan toner, copper phthalocyanine, which is Pigment Blue 15:3, or a mixture of copper phthalocyanine and aluminum phthalocyanine is preferable.

[0161] As the magenta toner, there can be used Pigment Red 53:1, Pigment Red 81, Pigment Red 122, Pigment Red 269, etc. These may be used alone or in combination of two or more.

[0162] As yellow toners, Pigment Yellow 74, Pigment Yellow 155, Pigment Yellow 180, Pigment Yellow 185, etc. can be used. These can be used alone or in combination of two or more. Among them, Pigment Yellow 185 or a mixture of Pigment Yellow 74 and Pigment Yellow 185 is preferred from the perspectives of chroma and storage stability.

[0163] As the white pigment, titanium dioxide subjected to surface treatment with silicon, zirconium oxide, aluminum, polyol, or the like can be used.

[0164] As a green toner, Pigment Green 7 or the like can be used, but safety precautions must be taken.

[0165] As the blue toner, Pigment Blue 15:1, Pigment Violet 23, or the like can be used.

[0166] The toner is preferably colorless (containing no colorant), white, or a slightly pale color, so as not to impair the hue of the overlying toner. Light colors are preferably yellow, black tea, or gray. Using the toner according to the embodiment as a base layer (the layer closest to the recording medium where an image is formed) can minimize impairment of the hue of the color toner when a color toner layer is formed thereon.

[0167] -External additives-

[0168] The external additive is not particularly limited and may be appropriately selected depending on the intended purpose. Examples of the external additive include inorganic fine particles.

[0169] As the above-mentioned inorganic fine particles, there are no particular restrictions and they can be appropriately selected according to the purpose. For example, silicon dioxide, aluminum oxide, titanium oxide, barium titanate, magnesium titanate, calcium titanate, strontium titanate, zinc oxide, quartz 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 them, silicon dioxide, aluminum oxide, and titanium oxide are preferred.

[0170] In addition, inorganic particles also can be used to carry out surface-treated inorganic particles by hydrophobizing treatment agent.As hydrophobizing treatment agent, can enumerate as surface treating agent and preferred for example, silane coupling agent, silylating agent, silane coupling agent with fluorinated alkyl, organic titanate coupling agent, aluminum coupling agent etc..In addition, silicone oil is used as hydrophobizing treatment agent, also can obtain sufficient effect.

[0171] -Flowability Improver-

[0172] The above-mentioned fluidity improver is not particularly limited as long as it is a fluidity improver that is surface-treated to improve hydrophobicity and can prevent deterioration of flow characteristics or charging characteristics even under high humidity. It can be appropriately selected according to the purpose, and examples thereof include silane coupling agents, silylating agents, silane coupling agents having a fluorinated alkyl group, organic titanate coupling agents, aluminum coupling agents, silicone oil, modified silicone oil, etc.

[0173] The silica and titanium oxide are preferably surface-treated with such a fluidity-improving agent and used as hydrophobic silica and hydrophobic titanium oxide.

[0174] - Cleansing agent -

[0175] The cleaning property improving agent is not particularly limited as long as it is added to the toner to remove the developer remaining on the photoreceptor or the primary transfer medium after transfer, and can be appropriately selected depending on the intended purpose.

[0176] The cleaning agent is not particularly limited and can be appropriately selected depending on the intended purpose. Examples thereof include fatty acid metal salts such as zinc stearate, calcium stearate, and stearic acid; and polymer particles produced by soap-free emulsion polymerization such as polymethyl methacrylate particles and polystyrene particles.

[0177] The volume average particle size of the polymer microparticles is not particularly limited and may be appropriately selected depending on the intended purpose. However, from the viewpoint of relatively narrow particle size distribution, it is preferably 0.01 μm or more and 1 μm or less.

[0178] -Magnetic materials-

[0179] The magnetic material is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include iron powder, magnetite, and ferrite. Among these, white is preferred from the viewpoint of color tone.

[0180] <Toner Manufacturing Method>

[0181] The following describes a method for producing a toner. The toner production method according to one embodiment includes a step of obtaining a mixture of a binder resin (mixing step), a step of obtaining a kneaded product of the mixture (melt-kneading step), a step of obtaining a solid product of the kneaded product (solidification step), a step of obtaining a pulverized product of the solid product (fine pulverization step), and a step of classifying and recovering the pulverized product (classification step).

[0182] First, a binder resin, a colorant, a release agent, and, if necessary, a charge control agent, etc. are mixed using a mixer such as a Henschel mixer or a super mixer to obtain a mixture (mixing step).

[0183] Next, the mixture is melt-kneaded using a hot melt kneading machine such as a heating roll, a kneader, or an extruder to obtain a kneaded product (melt-kneading step).

[0184] Next, the kneaded product is cooled and solidified to obtain a solid product (solidification step). The cooling method and the solidification method are not particularly limited, and any appropriate method can be used.

[0185] Next, the solids are finely pulverized to obtain a solid pulverized product (fine pulverization step). The solids can be pulverized using a known pulverization method. Examples of pulverization methods include a jet mill method in which the toner is contained in a high-speed airflow and the energy generated when the toner collides with a collision plate is utilized to pulverize the solids; an interparticle collision method in which the toner collides with each other in the airflow; and a mechanical pulverization method in which the toner is fed between a high-speed rotating rotor and a narrow gap to pulverize the solids.

[0186] Next, the pulverized material is classified to recover pulverized material having a predetermined volume average particle size. In this way, a toner can be obtained (classification step). The classification method is not particularly limited, and any method can be used as appropriate.

[0187] In addition, the toner according to one embodiment can be manufactured using a dissolution suspension method. When the dissolution suspension method is used to produce the toner, the oil phase in which the toner materials such as the binder resin, colorant, release agent, and the charge control agent further added as needed are dissolved or dispersed in an organic solvent is dispersed into an aqueous medium (aqueous phase) to react the binder resin. Thus, a dispersion containing a dispersion (oil droplets) is obtained, and the dispersion contains a prepolymer in which the toner material is emulsified or dispersed. Then, the organic solvent is removed from the dispersion, filtered, washed and dried, and the mother particles of the toner are manufactured by performing classification as needed. The toner involved in one embodiment can be obtained by granulating the mother particles obtained using the dissolution suspension method.

[0188] The organic solvent is not particularly limited and may be appropriately selected depending on the intended purpose. From the viewpoint of easy removal, an organic solvent having a boiling point of lower than 150° C. is preferred.

[0189] The organic solvent having a boiling point below 150°C is not particularly limited and can be appropriately selected depending on the intended purpose. Examples thereof include toluene, xylene, benzene, carbon tetrachloride, dichloromethane, 1,2-dichloroethane, 1,1,2-trichloroethane, trichloroethylene, chloroform, monochlorobenzene, dichloroethylene, 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, dichloromethane, 1,2-dichloroethane, chloroform, and carbon tetrachloride are preferred, with ethyl acetate being more preferred.

[0190] As the above-mentioned aqueous medium, there is no particular limitation and it can be appropriately selected according to the purpose. For example, water, a solvent miscible with water, a mixture thereof etc. can be listed. These can be used alone or in combination of two or more. Among them, water is preferred.

[0191] As the solvent miscible with water, it is possible to select it appropriately according to the purpose, for example, alcohols, lower ketones, dimethylformamide, tetrahydrofuran, cellosolves, etc. There are no particular restrictions on the alcohol, and it is possible to select it appropriately according to the purpose, for example, methanol, isopropyl alcohol, ethylene glycol, etc. As the lower ketones, it is possible to select it appropriately according to the purpose, for example, acetone, methyl ethyl ketone, etc.

[0192] There are no particular limitations on the method for removing the organic solvent from the dispersion and the method may be appropriately selected depending on the intended purpose. Examples include a method in which the temperature of the entire reaction system is slowly raised 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.

[0193] The classification may be performed by removing fine particles in the liquid using a cyclone separator, a decanter, centrifugal separation or the like, or the classification operation may be performed after drying.

[0194] Furthermore, the toner according to one embodiment has a low melting point and can be made difficult to crystallize, thereby having excellent heat-resistant storage stability. Heat-resistant storage stability can be evaluated by measuring the amount of aggregates generated in the toner after storage in a high-temperature, high-humidity environment (e.g., 40°C and 70% RH) for a long period of time (e.g., 14 days).

[0195] <Developer>

[0196] The developer according to one embodiment includes the toner according to one embodiment, and may include other appropriately selected components such as a carrier, as needed.

[0197] The developer may be a single-component developer or a two-component developer. However, when used in high-speed printers corresponding to recent increases in information processing speed, two-component developers are preferred from the viewpoint of improving life.

[0198] When the colorant of one embodiment is used as a single-component developer, even if the colorant is collected and spent, the particle size of the colorant changes little, the film formation of the colorant on the developing roller, and the melting and adhesion of the colorant on components such as the scraper that thins the colorant layer are less, and even under long-term stirring in the developing device, good and stable developability and images can be obtained.

[0199] When the developer of one embodiment is used as a two-component developer, it can be mixed with a carrier to be used as a developer. When the toner of one embodiment is used as a two-component developer, even with long-term toner storage and disbursement, the toner particle size fluctuates little, and even with long-term stirring in a developing device, excellent and stable developability and images can be obtained.

[0200] The content of the carrier in the two-component developer can be appropriately selected depending on the purpose, and 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.

[0201] The developer according to one embodiment can suitably form an image by various known electrophotographic methods such as a magnetic single-component developing method, a non-magnetic single-component developing method, and a two-component developing method.

[0202] [Carrier]

[0203] As a carrier, magnetic particles can be used. As magnetic particles, spinel ferrites such as magnetite, gamma iron oxide, spinel ferrites containing one or more of metals other than iron (Mn, Ni, Zn, Mg, Cu, etc.), magnetoplumbite ferrites such as barium ferrite, and particles of iron or alloys having an oxide layer on the surface can be used. Considering chemical stability, magnetite, spinel ferrites containing gamma iron oxide, magnetoplumbite ferrites such as barium ferrite, etc. are preferably used. Specifically, as suitable examples, MFL-35S, MFL-35HS (made by Powdertech), DFC-400M, DFC-410M, SM-350NV (made by Tonghe Iron Powder Industry Co., Ltd.) and the like can be listed.

[0204] In particular, when a carrier needs to have high magnetization, it is preferable to use ferromagnetic fine particles such as iron as the carrier.

[0205] The shape of the carrier may be any of granular, spherical, and needle-like.

[0206] By appropriately selecting the type and content of the carrier, a resin carrier having a desired magnetization can be used. The magnetic properties of the resin carrier in this case preferably have a magnetization intensity of 30 to 150 emu / g at 1000 oersteds.

[0207] Such a resin carrier can be produced by spraying a melt-kneaded product of the carrier and the 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 to produce a resin carrier in which the carrier is dispersed in a condensation-type binder.

[0208] The surface of the carrier may be fixed with positively or negatively charged microparticles or conductive microparticles, or coated with a resin to control the chargeability.

[0209] As the surface coating material (resin), silicone resin, acrylic resin, epoxy resin, fluorine resin, etc. can be used. Furthermore, positively or negatively charged particles or conductive particles can be contained for coating, among which silicone resin and acrylic resin are preferred.

[0210] The weight ratio of the carrier in the developer contained in the developing device is preferably 85% to less than 98% by mass. A weight ratio of 85% to less than 98% by mass effectively suppresses toner scattering from the developing device, reducing the occurrence of image defects. Furthermore, since excessive increases in the charge level of the electrophotographic toner or insufficient supply of electrophotographic toner can be suppressed, image defects caused by reduced image density can be reduced.

[0211] <Developer Storage Container>

[0212] The developer storage container according to one embodiment stores the developer according to one embodiment. The developer storage container is not particularly limited and can be appropriately selected from known containers, including containers having a container body and a lid.

[0213] In addition, the size, shape, structure, material, etc. of the container body are not particularly limited. The shape of the container body is preferably a cylindrical shape such as a cylinder, and preferably has a spirally formed concave-convex portion on the inner circumference. By rotating the container body, the developer as the content easily moves toward the discharge port side. In addition, it is more preferred that a part or all of the concave-convex portion is formed into a corrugated shape. Thereby, the developer is more likely to move toward the discharge port side. In addition, the material is not particularly limited, and a material with high dimensional accuracy is preferably used. For example, resin materials such as polyester resin, polyethylene resin, polypropylene resin, polystyrene resin, polyvinyl chloride resin, polyacrylic acid, polycarbonate resin, ABS resin, and polyacetal resin can be listed.

[0214] The developer container is easy to store and transport and has excellent operability. Therefore, it can be detachably mounted on an image forming apparatus, a process cartridge, etc., which will be described later, and used for replenishing the developer.

[0215] <Toner Set>

[0216] The toner set according to one embodiment may include a color toner containing a binder resin and a colorant, and the toner according to one embodiment.

[0217] There are no particular limitations on the color toner, and any known color toner may be appropriately selected depending on the intended purpose. There are no particular limitations on the binder resin, and any suitable selection may be made depending on the intended purpose. For example, the same binder resin as that contained in the toner of one embodiment may be used. There are no particular limitations on the colorant, and any known colorant may be appropriately selected depending on the intended purpose.

[0218] By mounting the toner set of one embodiment on an image forming apparatus and performing image formation, image formation can be performed using the toner of one embodiment, thereby performing image formation utilizing the characteristics of the toner having excellent fixing properties to cloth.

[0219] Toner storage unit

[0220] A toner storage unit according to one embodiment can store the toner according to one embodiment. A toner storage unit according to one embodiment is a unit that stores toner and has the function of storing toner. Examples of the toner storage unit include a toner container, a developer, and a process cartridge.

[0221] The toner container is a container that stores toner.

[0222] The developing device is a device that has a mechanism for storing toner and performing development.

[0223] The so-called process cartridge is a device that integrates at least an electrostatic latent image carrier (also called an image carrier) and a developing mechanism, stores toner, and is detachably mounted on an image forming device. The process cartridge may further include at least one selected from a charging mechanism, an exposure mechanism, and a cleaning mechanism.

[0224] A toner storage unit according to one embodiment stores the toner according to one embodiment. By attaching the toner storage unit according to one embodiment to an image forming apparatus and performing image formation, image formation using the toner according to one embodiment is performed, thereby enabling image formation that utilizes the characteristics of the toner having excellent fixing properties to cloth.

[0225] (Toner storage unit)

[0226] The toner storage unit in the present invention is a unit that stores the toner of the present invention in a unit having a function of storing toner. Examples of the toner storage unit include a toner storage container, a developer, and a process cartridge.

[0227] The above-mentioned toner storage container refers to a container that stores toner.

[0228] When the above-mentioned toner is used as a developer, the toner container is sometimes referred to as a developer container.

[0229] The developer storage container is not particularly limited and may be appropriately selected from known containers, and examples thereof include containers having a container body and a lid.

[0230] The size, structure, material, etc. of the container body of the toner container and the developer container are not particularly limited.

[0231] The shape of the developer storage container's main body is not particularly limited and can be appropriately selected depending on the intended purpose. Preferably, the shape is cylindrical, such as a cylinder, with a spirally shaped concave-convex portion on the inner circumference. Rotating the container main body facilitates movement of the developer, the contents, toward the discharge port. More preferably, a portion or all of the concave-convex portion is formed in a corrugated shape. This facilitates movement of the developer toward the discharge port.

[0232] The materials of the above-mentioned colorant storage container and the above-mentioned developer storage container are not particularly limited and can be appropriately selected according to the purpose, but materials with high dimensional accuracy are preferred. For example, resin materials such as polyester resin, polyethylene resin, polypropylene resin, polystyrene resin, polyvinyl chloride resin, polyacrylic acid, polycarbonate resin, ABS resin, and polyacetal resin can be listed.

[0233] The toner container and the developer container are easy to store and carry and have excellent handleability. Therefore, they can be detachably mounted on an image forming apparatus, a process cartridge, etc. to be described later for replenishing toner and developer.

[0234] The developing device is a developing apparatus having a mechanism for storing toner and developing the toner.

[0235] The process cartridge is a process cartridge that integrates at least an electrostatic latent image carrier (also referred to as an image carrier) and a developing mechanism, stores toner, and is removably mounted on an image forming apparatus. The process cartridge may further include at least one selected from a charging unit, an exposure unit, and a cleaning unit.

[0236] (Image Forming Apparatus and Image Forming Method)

[0237] The image forming apparatus of the present invention includes: an electrostatic latent image carrier; an electrostatic latent image forming unit for forming an electrostatic latent image on the electrostatic latent image carrier; a developing unit for developing the electrostatic latent image formed on the electrostatic latent image carrier using toner to form a toner image; a transfer unit for transferring the toner image to a recording medium; and a fixing unit for fixing the transferred image to the recording medium. The image forming apparatus may further include other units as needed.

[0238] The image forming method of the present invention includes: 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 transferring step of transferring the toner image to a recording medium; and a fixing step of fixing the transferred image onto the recording medium. The image forming method of the present invention is characterized in that the toner image is formed using the toner of the present invention. Other steps may be included as needed.

[0239] The image forming method can be suitably performed by the image forming device, the electrostatic latent image forming process can be suitably performed by the electrostatic latent image forming portion, the developing process can be suitably performed by the developing portion, the transfer process can be suitably performed by the transfer portion, the fixing process can be suitably performed by the fixing portion, and the other processes can be suitably performed by the other portions.

[0240] <Electrostatic latent image carrier>

[0241] The material, structure, and size of the electrostatic latent image bearing member (hereinafter sometimes referred to as a “photoreceptor”) are not particularly limited and can be appropriately selected from known ones.

[0242] Examples of the material of the electrostatic latent image bearer include an inorganic photoreceptor and an organic photoreceptor.

[0243] Examples of the inorganic photoreceptor include amorphous silicon and selenium.

[0244] As the above-mentioned organic photoreceptor, there can be cited a laminated photoreceptor having a laminated structure on a support such as an aluminum drum, wherein the laminated structure is formed by dispersing a charge generating material such as metal-free phthalocyanine or titanyl phthalocyanine in a binder resin (charge generating layer), and a layer (charge transport layer) in which a charge transport material is dispersed in a binder resin. As the above-mentioned organic photoreceptor, there can also be cited a single-layer photoreceptor, wherein the single-layer photoreceptor has a photosensitive layer with a single-layer structure, in which both the charge generating material and the charge transport material are dispersed in a binder resin on a support. In the above-mentioned single-layer photoreceptor, a hole transport agent and an electron transport agent can also be added to the photosensitive layer as charge transport materials. A primer layer can be provided between the support and the laminated charge generating layer or the single-layer photosensitive layer.

[0245] The shape of the electrostatic latent image carrier is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably cylindrical. The outer diameter of the cylindrical electrostatic latent image carrier is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 3 mm to 100 mm, more preferably 5 mm to 50 mm, and particularly preferably 10 mm to 30 mm.

[0246] <Electrostatic Latent Image Forming Section and Electrostatic Latent Image Forming Step>

[0247] The electrostatic latent image forming unit in the image forming apparatus of the present invention is not particularly limited as long as it is a mechanism for forming an electrostatic latent image on an electrostatic latent image bearing member, and can be appropriately selected depending on the intended purpose. The electrostatic latent image forming unit includes, for example, a charging device (charger) for uniformly charging the surface of the electrostatic latent image bearing member and an exposure device (exposing device) for exposing the surface of the electrostatic latent image bearing member to an image-like shape.

[0248] The electrostatic latent image forming process in the image forming method of the present invention is a process for forming an electrostatic latent image on an electrostatic latent image carrier, including a charging process for charging the surface of the electrostatic latent image carrier and an exposure process for exposing the surface of the charged electrostatic latent image carrier to form an electrostatic latent image.

[0249] Charging can be performed by, for example, applying a voltage to the surface of the electrostatic latent image bearing member using a charging device (charger).

[0250] The exposure can be performed, for example, by exposing the surface of the electrostatic latent image bearing member in an image-wise manner using an exposure device (exposing apparatus).

[0251] The electrostatic latent image can be formed by, for example, uniformly charging the surface of the electrostatic latent image carrier and then exposing it imagewise, and can be performed by the electrostatic latent image forming unit.

[0252] -Charging device (charger)-

[0253] The charger is not particularly limited and can be appropriately selected depending on the purpose. Examples include contact chargers having a conductive or semiconductive roller, brush, film, or rubber blade, and non-contact chargers utilizing corona discharge such as corotrons and scorotrons.

[0254] The shape of the charger may be any shape other than a roller, such as a magnetic brush or a fur brush, and can be selected according to the specifications and form of the image forming apparatus.

[0255] The charger is preferably one that is disposed in contact or non-contact with the electrostatic latent image carrier and charges the surface of the electrostatic latent image carrier by superimposing DC and AC voltages. Furthermore, the charger is preferably a charging roller that is disposed in non-contact proximity to the electrostatic latent image carrier with a gap between the rollers, and charges the surface of the electrostatic latent image carrier by superimposing DC and AC voltages on the charging roller.

[0256] The charger is not limited to a contact-type charger, but is preferably a contact-type charger from the viewpoint of obtaining an image forming apparatus that reduces ozone generated from the charger.

[0257] -Exposure device (exposure device)-

[0258] The above-mentioned exposure device is not particularly limited as long as it can expose the surface of the above-mentioned electrostatic latent image carrier charged by the above-mentioned charger to form the required image. It can be appropriately selected according to the purpose. For example, various exposure devices such as copying optical systems, rod lens array systems, laser optical systems, liquid crystal shutter optical systems, etc. can be listed.

[0259] The light source used in the above-mentioned exposure device is not particularly limited and can be appropriately selected according to the purpose. For example, all 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) can be mentioned.

[0260] In addition, in order to irradiate only light in a desired wavelength region, various filters such as a sharp cut filter, a bandpass filter, a near-infrared cut filter, a dichroic filter, an interference filter, and a color temperature conversion filter may be used.

[0261] A backlight method may also be employed in which the electrostatic latent image carrier is exposed to light from the back side thereof.

[0262] <Developing Section and Development Process>

[0263] 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 bearing member to form a toner image, and can be appropriately selected depending on the intended purpose. For example, a developer including a toner container that stores toner and can apply toner to the electrostatic latent image in a contact or non-contact manner, or a developer including a toner container can be preferably used as the developing unit.

[0264] The developing step in the image forming method of the present invention is a step of sequentially developing the electrostatic latent image with a plurality of color toners to form a toner image. The toner image can be formed by developing the electrostatic latent image using the above-mentioned toner, for example, and can be performed using a developer.

[0265] In the developing section and the developing step, the toner of one embodiment is used. Preferably, a toner image can be formed by using a developer containing the toner of one embodiment and, if necessary, other components such as a carrier.

[0266] The developer may be a monochrome developer or a multi-color developer. For example, the developer is preferably a developing device comprising a stirrer for frictionally stirring and charging the toner, a magnetic field generator fixed therein, and a rotatable developer carrier on which a developer containing the toner is placed.

[0267] Inside the developer, for example, toner and carrier are mixed and stirred. This friction causes the toner to become charged and held in an upright state on the surface of a rotating magnetic roller, forming a magnetic brush. Because the magnetic roller is positioned near the electrostatic latent image carrier (photoreceptor), a portion of the toner forming the magnetic brush on the magnetic roller surface is moved to the surface of the electrostatic latent image carrier (photoreceptor) by an electrical attraction force. As a result, the electrostatic latent image is developed with the toner, forming a toner image on the surface of the electrostatic latent image carrier (photoreceptor).

[0268] The image forming apparatus of the present invention may include a developing unit for color toners (black, cyan, magenta, and yellow) and a developing unit for the toner of the present invention, totaling five developing units. The toner of the present invention may be any color, but is preferably colorless or white. In one embodiment, the developing unit may use some or all of the black, cyan, magenta, and yellow color toners as the toner.

[0269] Alternatively, a premixed development method can be used, which replenishes a premixed developer consisting of premixed toner and carrier. In this 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 associated with developer degradation or reduce developer replacement time.

[0270] <Transfer Section and Transfer Process>

[0271] The transfer unit in the image forming apparatus of the present invention preferably comprises a primary transfer unit for transferring the toner image to an intermediate transfer member to form a composite transfer image, and a secondary transfer unit for transferring the composite transfer image to a recording medium. The intermediate transfer member is not particularly limited and can be appropriately selected from known transfer members depending on the intended purpose. For example, a transfer belt is preferably used.

[0272] The transfer process in the image forming apparatus of the present invention is a process for transferring a toner image onto a recording medium. The transfer process is preferably a mode in which the toner image is primarily transferred onto an intermediate transfer member using an intermediate transfer member, and then the toner image is secondarily transferred onto the recording medium.

[0273] More preferably, the transfer process includes: a first transfer process, using two or more colors of colorants, preferably full-color colorants, to transfer the colorant image to the intermediate transfer body to form a composite transfer image; and a second transfer process, transferring the composite transfer image to the recording medium.

[0274] The transfer can be performed, for example, by charging the electrostatic latent image carrier (photoreceptor) using a transfer charger, and can be performed by the transfer section described above.

[0275] The transfer units (primary transfer unit and secondary transfer unit) preferably include at least a transfer device that peels off the toner image formed on the electrostatic latent image carrier (photoreceptor) and charges it to the recording medium. The transfer units may be one or two or more.

[0276] Examples of the transfer tool include a corona transfer tool using corona discharge, a transfer belt, a transfer roller, a pressure transfer roller, and an adhesive transfer tool.

[0277] The recording medium is typically plain paper, but any recording medium to which an unfixed image after development can be transferred is not particularly limited and can be appropriately selected depending on the intended purpose. Release paper, PET film for OHP, and the like can also be used.

[0278] <Fixing Section and Fixing Process>

[0279] The fixing unit in the image forming apparatus of the present invention is not particularly limited and can be appropriately selected according to the purpose, and is preferably a known heating and pressing unit. Examples of the heating and pressing unit include a combination of a heating roller and a pressing roller, a combination of a heating roller, a pressing roller, and an endless belt, and the like.

[0280] The fixing process in the image forming apparatus of the present invention is a process for fixing the colorant image transferred to the recording medium using a fixing device. This process can be performed each time each color developer is transferred to the recording medium, or can be performed simultaneously at once while each color developer is stacked.

[0281] The above-mentioned fixing section is preferably a heating and pressing section, which includes a heating body having a heating element, paper or release paper in contact with the heating body, and a pressing member pressed against the heating body through the paper or release paper, so that the recording medium with an unfixed image is heated and fixed between the film and the pressing member.

[0282] The heating in the heating and pressurizing section is preferably performed at 80°C to 200°C in general.

[0283] The surface pressure of the heating and pressing part is not particularly limited and can be appropriately selected according to the purpose, but is preferably 10 N / cm 2 Above 80N / cm 2 the following.

[0284] In this embodiment, depending on the purpose, for example, a known optical fixer may be used together with the fixing unit, or a known optical fixer may be used instead of the fixing unit.

[0285] <Other departments and other processes>

[0286] In addition to the above-described configuration, the image forming apparatus of the present invention may further include other components, such as a static eliminating component, a cleaning component, a recycling component, and a control component, as appropriate, as needed.

[0287] In addition to the above-mentioned steps, the image forming method of the present invention may further include other steps, such as a neutralization step, a cleaning step, and a recycling step, as appropriate, as needed.

[0288] 《Static removal department and static removal process》

[0289] The static eliminator is not particularly limited as long as it can apply a static eliminator bias to the electrostatic latent image bearer, and can be appropriately selected from known static eliminators. For example, a static eliminator lamp is preferred.

[0290] The static elimination step is a step of applying a static elimination bias to the electrostatic latent image bearing member to eliminate static electricity, and can be preferably performed by the static elimination section.

[0291] Cleaning Department and Cleaning Process

[0292] The cleaning unit is not particularly limited as long as it can remove the toner remaining on the electrostatic latent image carrier, and can be appropriately selected from known cleaners. Examples of the cleaning unit include a magnetic brush cleaner, an electrostatic brush cleaner, a magnetic roller cleaner, a scraper cleaner, a brush cleaner, and a drum cleaner.

[0293] The cleaning step is a step of removing the toner remaining on the electrostatic latent image bearing member, and can be suitably performed by a cleaning unit.

[0294] The image forming apparatus of the present invention can improve cleanliness by including the above-mentioned cleaning section. Specifically, by controlling the adhesion between toners, the fluidity of the toners can be controlled, thereby improving cleanliness. Furthermore, by controlling the properties of degraded toners, excellent cleaning quality can be maintained even under harsh conditions such as extended lifespan or high temperature and humidity. Furthermore, since external additives can be fully released from the toners on the photoreceptor, high cleanliness can be achieved by forming a deposited layer (dam layer) of the external additives in the clamping portion of the cleaning blade.

[0295] Recycling Department and Recycling Process

[0296] The recycling unit is not particularly limited, and a known conveying mechanism and the like can be used.

[0297] The recycling step is a step of recycling the toner removed in the cleaning step to the developing section, and can be preferably performed by the recycling section.

[0298] Control Department

[0299] The control unit can control the operation of each of the above-mentioned units. There is no particular limitation on the control unit as long as it can control the operation of each of the above-mentioned units. The control unit can be appropriately selected according to the purpose. For example, a sequencer, a computer, or other control device can be mentioned.

[0300] The image forming apparatus according to one embodiment can form an image using the toner according to one embodiment, and therefore has excellent fixing properties to cloth, can suppress power consumption, and can stably provide high-quality images.

[0301] Here, refer to Figure 3 An embodiment of an image forming apparatus will be described below. However, the application of the present invention is not limited to these embodiments.

[0302] In each accompanying drawing, identical structural parts are marked with the same reference numerals, and repeated explanation is sometimes omitted. In addition, the quantity, position, shape etc. of following constituent parts are not limited to this embodiment, and preferred quantity, position, shape etc. can be adopted when implementing the present invention.

[0303] Figure 3 This is a schematic diagram showing an example of an image forming apparatus according to an embodiment.

[0304] Figure 3 The image forming apparatus shown is a so-called tandem-type 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. A full-color image is formed by superimposing the toner images of yellow (Y), cyan (C), magenta (M), and black (K) formed by each toner image forming unit. The arrangement of the toner image forming units for each color is not particularly limited.

[0305] Each of the toner image forming units 20Y, 20C, 20M, and 20K includes a photoreceptor drum 4Y, 4C, 4M, and 4K, respectively, which serves as an image carrier and is driven to rotate. Furthermore, each of the photoreceptor drums 4Y, 4C, 4M, and 4K is provided with an exposure device 45 that forms a latent image by exposing the drum to laser light or LED light based on image information for each color.

[0306] An intermediate transfer belt 60, serving as an intermediate transfer member, is movably disposed so as to face the toner image forming units 20Y, 20C, 20M, and 20K. Primary transfer rollers 61Y, 61C, 61M, and 61K are disposed at positions facing the photoreceptor drums 4Y, 4C, 4M, and 4K across the intermediate transfer belt 60. These rollers transfer the toner images of the respective colors formed on the photoreceptor drums 4Y, 4C, 4M, and 4K onto the intermediate transfer belt 60.

[0307] The primary transfer rollers 61Y, 61C, 61M, and 61K sequentially transfer the toner images of the respective colors formed by the toner image forming units 20Y, 20C, 20M, and 20K described later onto the intermediate transfer belt 60 and superimpose them to form a full-color image.

[0308] A paper feed unit 70, consisting of a paper feed cassette 71 and paper feed rollers 72, is located at the bottom of the image forming apparatus. Transfer paper is fed to registration rollers 73. Registration rollers 73, in sync with the timing of toner image formation, feed the transfer paper to the opposing portion of the intermediate transfer belt 60 and the secondary transfer device 65. The full-color toner image on the intermediate transfer belt 60 is transferred to the transfer paper by the secondary transfer device 65, fixed by the fixing device 90, and then discharged outside the apparatus.

[0309] Next, the toner image forming units 20Y, 20C, 20M, and 20K will be described. The toner image forming units 20Y, 20C, 20M, and 20K have substantially the same structure and operation, except for the difference in the color of the toner they store. Therefore, the subscripts Y, C, M, and K used to distinguish between the colors will be omitted in the following description, and the structure and operation of the toner image forming unit 20 will be described.

[0310] Figure 4 This is a schematic diagram illustrating the main configuration of an image forming apparatus in one embodiment. The toner image forming unit 20 is surrounded by the photoreceptor drum 4, and includes various mechanisms for performing electrophotographic processing, such as a charging device 40, a developing device 50, and a cleaning device 30. These mechanisms form toner images of various colors on the photoreceptor drum 4 through well-known operations. The toner image forming unit 20 may be an integrally formed process cartridge that is removable from the main body of the image forming apparatus.

[0311] Figure 5 This is a schematic diagram showing the main structure of another example of an image forming apparatus having five developing devices. Description of points common to the above-mentioned image forming apparatus will be omitted.

[0312] The image forming apparatus of this embodiment includes a photoreceptor (photoreceptor 5, photoreceptor 11, photoreceptor 17, photoreceptor 23, photoreceptor 29), and is provided with chargers (charger 6, charger 12, charger 18, charger 24, charger 30), developing mechanisms (developing mechanism 8, developing mechanism 14, developing mechanism 20, developing mechanism 26, developing mechanism 32), transferers (transferer 10, transferer 16, transferer 22, transferer 28, transferer 34), cleaning devices (cleaning device 9, cleaning device 15, cleaning device 21, cleaning device 27, cleaning device 33), and an intermediate transfer belt cleaning device 42 around the photoreceptors, and irradiates the photoreceptors with exposure light (exposure light 7, exposure light 13, exposure light 19, exposure light 25, exposure light 31).

[0313] Furthermore, the intermediate transfer belt cleaning device 42 may be provided with a collecting mechanism for receiving the removed toner, etc. As the collecting mechanism, a dish-shaped tray, etc. may be used.

[0314] The developer unit for each color includes the aforementioned photoreceptor, charger, developing mechanism, cleaning device, and the like. Developer unit 35 uses white or transparent toner, developer unit 36 uses black toner, developer unit 37 uses cyan toner, developer unit 38 uses magenta toner, and developer unit 39 uses yellow toner to form images, which are then transferred to intermediate transfer belt 40. The image formed on intermediate transfer belt 40 is transferred to a recording medium by transfer device 41 and fixed by fixing device 43. A paper feed cassette 1 and paper feed roller 2 are located below the developer unit, feeding transfer paper to registration rollers 3 and 4. Registration rollers 3 and 4 feed the transfer paper to the opposing portion of intermediate transfer belt 40 and transfer device 41 in sync with the timing of toner image formation.

[0315] In this embodiment, an elastic intermediate transfer belt may be used as the intermediate transfer belt 40. As the elastic intermediate transfer belt, for example, a belt having a soft elastic layer laminated on a rigid base layer that can provide relatively good flexibility may be used.

[0316] Furthermore, in order to prevent the intermediate transfer belt 40 from meandering, a deflection preventing guide member may be provided on the inner peripheral surface of the intermediate transfer belt 40 .

[0317] [Example]

[0318] Hereinafter, the present invention will be described in more detail based on examples, but the technical scope of the present invention is not limited at all to the following examples.

[0319] In the following description, "parts" means "parts by mass" and "%" means "% by mass" unless otherwise specified.

[0320] <Preparation of antiviral agents>

[0321] Antiviral Agent A: 45.0 parts of commercially available copper (I) iodide powder (Wako Pure Chemical Industries, Ltd.) as CuI microparticles, 1.0 part of a surfactant, and 54.0 parts of zirconium oxide particles (Nippon Denko Industries, Ltd.) as inorganic compound microparticles were pre-dispersed in 800.0 parts of methanol. The mixture was then crushed and dispersed using a bead mill to obtain a slurry of copper (I) iodide microparticles coated with or supported by zirconium oxide. The average primary particle size of this mixture was 120 nm.

[0322] This was dried to obtain a mixed powder of the antiviral agent A. Since the powder has a certain degree of cohesion, the dispersed particle size in the toner is defined as the fine particles including the cohesion.

[0323] Antiviral Agents B and C: A powder mixture of Antiviral Agents B and C was prepared in the same manner as Antiviral Agent A, except that the amounts of copper iodide and zirconium oxide were changed.

[0324] Antiviral Agent D and Antiviral Agent 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 inorganic dispersants.

[0325] In addition, Zeomic Type AJ (manufactured by CinnaZeomic Co., Ltd.) was used as the Ag-based antibacterial material F.

[0326] The compositions of antiviral agents A to E are shown in the following Table 2. The unit of the numerical values in the table is "parts".

[0327] Table 2

[0328]

[0329] <Preparation of Antiviral Toner Masterbatch 1>

[0330] Prepare 30 parts of a polymer dispersant, 27 parts of a polyethylene resin, and 3 parts of polyethylene glycol, dissolve and mix them in a toluene solvent, disperse them using a ball mill, add a slurry of the above-mentioned antiviral material C with a solid content of 40% (400 parts as a slurry, 40 parts solid content), further disperse them, and dry them to obtain [masterbatch 1] of the antiviral colorant.

[0331] This [masterbatch 1] was used in Comparative Example 4 described later.

[0332] (Example 1)

[0333] <Preparation of Toner>

[0334] 45 parts of polyester resin 1 (RN-306 SF, 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 pre-mixed using a Henschel mixer (FM20B, manufactured by Nippon Coke Industries). The mixture was then melted and kneaded using a single-screw kneader (Buss kneader "MDK46-11D", manufactured by Buss Corporation) at a barrel feed rate 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 material.

[0335] The resulting kneaded product was cooled to room temperature and coarsely pulverized using a Rotoplex to a particle size of 200 to 300 μm. Next, the product was finely pulverized using a jet mill (100 AFG, manufactured by Hosokawa Micron) while appropriately adjusting the pulverization pressure to a mass average particle size of (6.5 ± 0.3) μm. The finely pulverized product was then classified using an air flow classifier (EJ-LABO, manufactured by Matsubo Co., Ltd.) while appropriately adjusting the shutter opening to a number average particle size Dp50 of (7.0 ± 0.3) μm, thereby obtaining toner base particles.

[0336] Next, 0.8 parts of HDK-2000 (registered trademark) (manufactured by Clariant), 0.5 parts of H05TD (registered trademark) (manufactured by Clariant), and 0.3 parts of MT-150IB (registered trademark) (manufactured by TAYCA) were added as additives to 100 parts of the above-mentioned toner base particles, and the mixture was stirred and mixed using a Henschel mixer. This yielded [Toner 1]. The toner particle size Dp50 at this point was 7.1 μm.

[0337] 3 g of the obtained [Toner 1] was weighed and pressed using a molding machine to produce pellets with a diameter of 3 cm. Fluorescent X-ray characterization was performed using the EZ mode. The intensities of Cu and Zr obtained were as follows:

[0338] Cu:912 kcps, Zr:2172 kcps.

[0339] In addition, the average dispersed particle size of the antiviral agent was 251 nm.

[0340] (Examples 2 to 7 and Comparative Examples 1 to 6)

[0341] 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.

[0342] The compositions of toners 1 to 13 are shown in Table 3-1 and Table 3-2.

[0343] Table 4 shows the fluorescent X-ray intensity of each toner.

[0344] Table 3-1

[0345]

[0346] Table 3-2

[0347]

[0348] The materials used in the compositions shown in Table 3-1 and Table 3-2 are as follows:

[0349] <Binder resin>

[0350] Polyester resin 1 (RN-306 SF, manufactured by Kao Corporation, low acid value resin, acid value: 8 mgKOH / g)

[0351] Polyester resin 2 (RN-290, manufactured by Kao Corporation, high acid value resin, acid value: 27 mgKOH / g)

[0352] Release agent

[0353] ·WAX (ester wax: WEP-5, manufactured by NOF Corporation)

[0354] Charge Control Agent

[0355] CCA (zirconium salicylate: TN-105, manufactured by Hodogaya Chemical Co., Ltd.)

[0356] Preparation of two-component developer

[0357] [Preparation of carrier]

[0358] A mixture of the following carrier raw materials was dispersed in a homogenizer for 20 minutes to prepare a coating liquid. Mn ferrite particles with a mass average particle size of 40 μm were used as the core material. Using a fluidized bed coating apparatus, with the temperature within the flow tank controlled at 70°C, the coating liquid was applied to an average film thickness of 0.20 μm on the core material surface, followed by drying. The resulting carrier was calcined in an electric furnace at 180°C for 2 hours to obtain Carrier A.

[0359] (Carrier raw materials)

[0360] Silicone resin (organic linear silicone): 100 parts

[0361] Toluene: 100 parts

[0362] γ-(2-aminoethyl)aminopropyltrimethoxysilane: 5 parts

[0363] Carbon black: 10 parts

[0364] [Preparation of two-component developer]

[0365] The toners prepared in Examples 1 to 7 and Comparative Examples 1 to 6 were uniformly mixed with Carrier A at 48 rpm for 5 minutes using a Turbula mixer (manufactured by Wiley-E-Bakefen (WAB)) to charge the toners and prepare two-component developers. The mixing ratio of the toner and Carrier A matched the toner concentration of the initial developer (7% by mass) in the evaluation machine to obtain the resulting developers.

[0366] The developers containing the toners prepared in Examples 1 to 7 and Comparative Examples 1 to 6 were used, and the evaluation results are shown in Table 4-1 and Table 4-2.

[0367] Table 4-1

[0368]

[0369] Table 4-2

[0370]

[0371] [Evaluation method]

[0372] The obtained two-component developer was used to carry out development using a modified copy machine (imagioMF7070, manufactured by Ricoh Co., Ltd.). Under an MM environment (temperature: 23°C, relative humidity: 50% RH), the print speed was 5,000 sheets / day initially and after 30K sheets (30,000 sheets), a white solid image and a black solid image, A4 size paper (variety: RICOH MyPaper, manufactured by Ricoh Co., Ltd.) were used, and the print mode was 40%, and the paper was continuously passed horizontally in A4 size.

[0373] The toners of the obtained samples were evaluated by the following methods.

[0374] <Antiviral properties>

[0375] The obtained two-component developer was used for development using a modified copy machine (imagioMF7070, manufactured by Ricoh Co.), 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. The image was then cut into multiple sheets of 5 cm square to prepare samples for antiviral testing.

[0376] The assessment criteria are based on the SIAA certification criteria.

[0377] Activity value: 2.0 or above, judged to be effective and set as OK.

[0378] As an antiviral test, samples without durability testing and samples with light resistance testing according to the durability testing method were tested in the influenza virus test according to ISO 021702. The evaluation results of antiviral activity are shown in Table 4.

[0379] In addition, an antiviral activity value of 2.0 or higher is a criterion for SIAA certification.

[0380] (Evaluation Criteria)

[0381] ◎: The antiviral activity value after treatment was 3.0 or higher in both the light resistance test and the non-durability test, indicating sufficient effectiveness. SIAA certification possible.

[0382] ○: The antiviral activity value after treatment (without durability test and with light resistance test) is 2.0 or higher and less than 3.0, indicating effectiveness. SIAA certification possible.

[0383] ×: If either or both of the antiviral activity values after treatment (without durability testing or with light resistance testing) are less than 2.0, the product is ineffective and SIAA certification cannot be obtained.

[0384] <Lightfastness>

[0385] Using a two-component developer, development was performed using a modified copy machine (imagio MF7070, manufactured by Ricoh Co., Ltd.). Samples for the light resistance test were prepared by printing on the front side of A4-sized paper (RICOH 180K paper, manufactured by Ricoh Co., Ltd.) cut in half using a 40% print mode. The paper was then cut into 4 cm square sheets to prepare samples.

[0386] (Light resistance test)

[0387] The light resistance test in the present invention refers to the following test:

[0388] Test device: No climate meter (Ci4000)

[0389] Irradiation conditions: 180W / m 2 Mode of irradiation only under accelerated conditions (without water)

[0390] 0 time:NEW(benchmark)

[0391] 7h irradiation: Condition 1

[0392] Using a two-component developer, a modified copy machine (imagio MF7070, manufactured by Ricoh) was used to develop a halftone image with a deposition rate of 0.5 mg / cm² on A4-sized paper in a MM environment (temperature: 23°C, humidity: 50% RH). The images were cut into 7 cm x 7 cm to 14 cm pieces and stored directly in the dark, with the time set as 0 hours (baseline). Samples were prepared under the irradiation conditions of Conditions 1 and 2 of the above-mentioned weather meter test, with the X-Rite ΔE = E(Condition 1) - E(NEW).

[0393] As light resistance evaluation, ΔE was evaluated and determined based on the following evaluation criteria.

[0394] [Evaluation Criteria]

[0395] ○: ΔE is 3 or less.

[0396] Δ: ΔE is greater than 3 and 5 or less, which is not a practical problem.

[0397] ×: ΔE is greater than 5, and the color tone changes greatly.

[0398] <Confirmation of heat-resistant storage and discoloration>

[0399] 10 g of the toner was placed in a plastic container and left unopened at 40°C and 70% humidity for 2 weeks.

[0400] Next, the degree of toner aggregation was assessed using a 200-mesh sieve as a measure of heat resistance. Discoloration due to moisture was also checked, along with a check to see if the toner's hue had significantly changed. Discoloration towards black tea was particularly common.

[0401] (Evaluation Criteria)

[0402] ○: Residue on sieve: less than 1 mg, and no discoloration.

[0403] △: Residue on sieve: less than 1 mg and discolored.

[0404] ×: Residue on sieve: more than 1 mg.

[0405] <Photoreceptor damage and image defects (stripe)>

[0406] The photoreceptor surface was observed using an optical microscope. Based on the observation results, damage to the photoreceptor that caused or was likely to cause image defects was evaluated according to the following criteria. Streak-like image defects were evaluated by observing image defects such as white streaks and photoreceptor periodic defects in halftone images, solid white images, and solid black images using a magnifying glass or an optical microscope in the same manner as the above-mentioned photoreceptor damage evaluation method. The number of image defects per A4-size sheet was measured and evaluated based on the following criteria.

[0407] [Evaluation Criteria]

[0408] ◯: The surface of the photoreceptor is very good, and there are no streak-like defects on the image.

[0409] △: Streaks were observed on the photoreceptor, but there were no more than three image defects within 10 mm in length and 0.5 mm in width. There were no image defects exceeding 10 mm in length or 0.5 mm in width, indicating no problems in practical use.

[0410] ×: Streaks were observed, and image defects were observed, which caused problems in practical use.

[0411] If three or more scratches or white or black deposits within 10 mm in length and 0.5 mm in width other than those listed above are observed, or if scratches or toner deposits exceeding 10 mm in length or exceeding 0.5 mm in width are observed, and streaks or image defects are observed on the image, there will be problems with actual use.

[0412] While the embodiments have been described above, they are presented as examples and the present invention is not limited thereto. The embodiments described above may be implemented in various other forms and may be combined, omitted, replaced, or modified in various ways without departing from the spirit of the invention. These embodiments and their modifications are intended to be within the scope and spirit of the invention and are encompassed by the invention as set forth in the claims and their equivalents.

[0413] As the form of the present invention, for example, it is the following form: (1)

[0415] An antiviral toner comprising toner particles, wherein the toner particles contain a binder resin and an antiviral agent, wherein:

[0416] The antiviral agent contains particles composed of CuI and an inorganic dispersant containing Zr,

[0417] The specific gravity of the inorganic dispersant is within the range of ±0.5 of the specific gravity of CuI,

[0418] The bonding resin is a polyester resin,

[0419] The number average particle size of the antiviral agent dispersed in the polyester resin is 500 nm or less,

[0420] In fluorescent X-ray measurement of the toner particles, the Cu X-ray intensity is 300 kcps or more, and the intensity ratio of the Zr X-ray intensity to the Cu X-ray intensity (Zr / Cu) is greater than 1.0. (2)

[0422] The antiviral toner according to (1) above, wherein the inorganic dispersant is Zr oxide, the X-ray intensity of Cu is 400 kcps or higher, and the intensity ratio of the X-ray intensity of Zr to the X-ray intensity of Cu (Zr / Cu) is 2.0 or higher and 6.0 or lower. (3)

[0424] 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 mapped by energy dispersive X-ray spectroscopy (EDX). (4)

[0426] The antiviral toner according to any one of (1) to (3) above, wherein the antiviral toner is colorless, white, light brown, or gray. (5)

[0428] The antiviral toner according to any one of (1) to (4) above, wherein the light fastness is ΔE ≤ 5 in a light fastness test of an image printed at an adhesion amount of 0.5 mg / cm. (6)

[0430] A toner storage unit, characterized in that it can store the antiviral toner described in any one of (1) to (5) above. (7)

[0432] An image forming device, comprising:

[0433] The toner storage unit described above (6);

[0434] An electrostatic latent image forming mechanism (means) for forming an electrostatic latent image on an electrostatic latent image carrier;

[0435] A developing mechanism (means) for developing the electrostatic latent image using the toner to form a toner image;

[0436] A transfer mechanism (means) for transferring the toner image to a recording medium;

[0437] The fixing mechanism (means) fixes the transferred image onto the recording medium. (8)

[0439] An image forming method, comprising:

[0440] Electrostatic latent image forming step, forming an electrostatic latent image on the electrostatic latent image carrier;

[0441] A developing step, using the toner described in any one of (1) to (5) above, developing the electrostatic latent image to form a toner image;

[0442] A transfer step of transferring the toner image to a recording medium;

[0443] The fixing step fixes the transferred image onto the recording medium.

Claims

1. An antiviral toner comprising toner particles, wherein the toner particles contain a binder resin and an antiviral agent, wherein: The antiviral agent contains particles composed of CuI and an inorganic dispersant containing Zr, The specific gravity of the inorganic dispersant is within the range of ±0.5 of the specific gravity of CuI, The bonding 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 fluorescent X-ray measurement of the toner particles, the Cu X-ray intensity is 300 kcps or more, and the intensity ratio of the Zr X-ray intensity to the Cu X-ray intensity (Zr / Cu) is greater than 1.

0.

2. The antiviral toner according to claim 1, characterized in that : The inorganic dispersant is Zr oxide, the X-ray intensity of Cu is 400 kcps or higher, and the intensity ratio of the X-ray intensity of Zr to the X-ray intensity of Cu (Zr / Cu) is 2.0 or higher and 6.0 or lower.

3. The antiviral toner according to claim 1 or 2, characterized in that : The dispersed particle size of the antiviral agent in the antiviral toner is mapped by energy dispersive X-ray spectroscopy (EDX), and 90% or more of the particles are 300 nm or less.

4. The antiviral toner according to claim 1 or 2, characterized in that : The antiviral toner is colorless, white, light brown, or gray.

5. The antiviral toner according to claim 1 or 2, characterized in that : The light resistance was ΔE ≤ 5 in a light resistance test of an image printed at an adhesion amount of 0.5 mg / cm.

6. A toner storage unit, characterized in that : The antiviral toner according to any one of claims 1 to 5 is accommodated.

7. An image forming apparatus, characterized in that: include: The toner storage unit according to claim 6; Electrostatic latent image forming means, forming an electrostatic latent image on the electrostatic latent image carrier; A developing means for developing the electrostatic latent image using the toner to form a toner image; Transfer mechanism, transferring the toner image to a recording medium; The fixing mechanism fixes the transferred image onto the recording medium.

8. An image forming method, characterized in that: include: Electrostatic latent image forming step, forming an electrostatic latent image on the electrostatic latent image carrier; A developing step, using the toner according to any one of claims 1 to 5, developing the electrostatic latent image to form a toner image; A transfer step of transferring the toner image to a recording medium; The fixing step fixes the transferred image onto the recording medium.

Images