Toner, toner storage unit, toner set, process cartridge, image forming apparatus, image forming method, and transfer sheet

Abstract

To provide a toner that can improve durability of an image and guarantee image quality.SOLUTION: An electrophotographic toner includes a binder resin containing polyester resin and polyurethane elastomer, a mold release agent, and a benzoin-based compound, and has a softening temperature Ts of less than 20°C and a tangent method glass-transition temperature Tg2nd of less than 0°C. The benzoin-based compound is preferably benzoin.SELECTED DRAWING: None

Description

[Technical Field]

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

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

[0003] To form a full-color image by electrophotography, a toner set is generally used that combines three process color toners, cyan, magenta, and yellow, with a black toner.

[0004] In recent years, as electrophotographic color image forming apparatuses have become more widespread, the applications of printed materials have expanded to a wide variety of fields. Particularly in the field of custom-made consumer goods, there is a growing need for electrophotographic printing on materials that cannot be printed (fixed) with conventional electrophotographic toners intended for printing on paper media. Specifically, there is a growing need for printing on fabric media such as sports team uniforms, shoes, and bags.

[0005] Patent Document 1 discloses a thermal transfer print sheet obtained using a pulverized toner for thermal transfer print sheets, which can adhere an image formed on a white background to a print object by heat melting without using an adhesive, and which does not damage the pulverizer.

[0006] Patent Document 2 discloses an image forming method that can suppress excessive temperature rise in the nip portion, form good images without problems such as hot offset, improve crease fixability and blocking resistance, and further reduce power consumption in the fixing process by achieving low-temperature fixing.

[0007] Patent Document 3 discloses a toner that has sufficient flexibility and can be sufficiently fixed to a medium made of flexible fibers such as cloth, to which conventional toners do not easily fix, by specifying the softening temperature Ts and the tangential glass transition temperature Tg2nd. Summary of the Invention [Problem to be solved by the invention]

[0008] The above-mentioned conventional technology can sufficiently fix images to a medium made of flexible fibers such as cloth, but when fixing to a material with poor breathability, the air cannot escape downward during fixing, and a thick toner layer is layered on top of it, causing the air to remain inside and resulting in surface defects. Therefore, from the perspective of a toner that can improve the durability of an image fixed to a medium made of flexible fibers and ensure image quality, it cannot be said that a fully satisfactory toner has been obtained, and there is room for further research. An object of the present invention is to provide a toner that can improve the durability of images and ensure image quality.

[0009] As a result of extensive research, the present inventors have found that the above problems can be solved by the present invention having the following configuration. The binder resin includes a polyester resin and a polyurethane elastomer, a release agent, and a benzoin-based compound, The softening temperature Ts is less than 20°C, The tangent glass transition temperature Tg2nd is less than 0°C. Electrophotographic toner characterized by: [Effects of the Invention]

[0010] According to the present invention, it is possible to provide a toner that can improve the durability of an image fixed on a medium made of flexible fibers and ensure image quality. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a schematic diagram illustrating an example of an image forming apparatus according to an embodiment of the present invention. [Figure 2] 1 is a schematic diagram illustrating a configuration of a main part of an example of an image forming apparatus according to an embodiment of the present invention. [Figure 3] 2 is a schematic diagram of a flow curve obtained when the characteristics of an example of a toner according to an embodiment of the present invention are measured using an elevated flow tester. DETAILED DESCRIPTION OF THE INVENTION

[0012] The toner of the present invention will now be described in detail. (toner) The toner of the present invention is characterized in that it has a softening temperature Ts of less than 20°C and a tangential glass transition temperature Tg2nd of less than 0°C. If the softening temperature Ts of the toner is 20° C. or higher, the toner image after fixing is likely to crack. If the tangential glass transition temperature Tg2nd is 0° C. or higher, the toner has poor rubber elasticity at room temperature, and the image formed on a flexible medium has poor stretchability and poor durability when worn or washed. The glass transition temperature Tg2nd is preferably from -30°C to -10°C.

[0013] The toner of the present invention contains a binder resin containing a polyester resin and a polyurethane elastomer, a release agent, and a benzoin-based compound, and may also contain a colorant, a charge control agent, an external additive, and other components (flowability improvers, cleaning improvers, magnetic materials) as needed. If the toner does not contain a benzoin-based compound, the air does not escape downwards when fixing to a material with poor breathability, and a thick layer of toner is layered on top of it, causing the air to remain inside and resulting in surface defects.

[0014] <Binder resin> In the present invention, the binder resin (fixing resin) used as a toner material can be any conventionally known resin. Examples include styrene-based resins (homopolymers or copolymers containing styrene or styrene substitutes) such as styrene, poly-α-styrenestyrene, styrene-chlorostyrene copolymer, styrene-propylene copolymer, styrene-butadiene copolymer, styrene-vinyl chloride copolymer, styrene-vinyl acetate copolymer, styrene-maleic acid copolymer, styrene-acrylate copolymer, styrene-methacrylate copolymer, styrene-α-methyl chloroacrylate copolymer, and styrene-acrylonitrile-acrylate copolymer; epoxy resins, vinyl chloride resins, rosin-modified maleic acid resins, phenolic resins, polyethylene resins, polypropylene resins, petroleum resins, polyurethane elastomers, polyester resins, ketone resins, ethylene-ethyl acrylate copolymers, xylene resins, and polyvinyl butyrate resins. The production method of these resins is not particularly limited, and bulk polymerization, solution polymerization, emulsion polymerization, suspension polymerization, and the like can be used.

[0015] The toner of the present invention contains at least a polyurethane elastomer as a binder resin. Polyurethane elastomers are generally excellent in tensile strength, abrasion resistance, elasticity, and oil resistance, making them suitable binder resins for the present invention. In terms of the composition of the polyurethane elastomer, it is preferable to use a polyurethane elastomer composed of 1,4-butanediol (1,6-hexanediol), adipic acid, diphenylmethane diisocyanate, etc. The specific trade name of the polyurethane elastomer used is not particularly limited and can be selected appropriately depending on the purpose. Examples include hot melt powder ECOFREEN POWDER (manufactured by ECOFREEN), T8175N (manufactured by DIC Covestro Polymer), and P22MBRNAT (manufactured by Nippon Miractoran Co., Ltd.).

[0016] The toner of the present invention contains a polyester resin as a binder resin. Polyester resins are generally suitable for the present invention because they can be fixed at low temperatures while maintaining heat-resistant storage stability, compared to other resins.

[0017] The polyester resin used in the present invention is preferably obtained by condensation polymerization of an alcohol and a carboxylic acid. The alcohol to be used is not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include glycols such as ethylene glycol, diene glycol, triethylene glycol, and propylene glycol, etherified bisphenols such as 1,4-bis(hydroxymeta)cyclohexane and bisphenol A, other dihydric alcohol monomers, and trihydric or higher polyhydric alcohol monomers.

[0018] The carboxylic acid is not particularly limited and can be appropriately selected depending on the purpose. Examples thereof include divalent organic acid monomers such as maleic acid, fumaric acid, phthalic acid, isophthalic acid, terephthalic acid, succinic acid, and malonic acid, and trivalent or higher polyvalent carboxylic acid monomers such as 1,2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid, 1,2,4-cyclohexanetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, 1,2,5-hexanetricarboxylic acid, 1,3-dicarboxyl-2-methylenecarboxypropane, and 1,2,7,8-octanetetracarboxylic acid.

[0019] The softening temperature Ts and the tangential glass transition temperature Tg2nd of the polyurethane elastomer are preferably both 45° C. or less. When the softening temperature Ts and the tangential glass transition temperature Tg2nd of the polyurethane elastomer are both 45° C. or less, the flexibility of the toner layer after fixing can be ensured.

[0020] The softening temperature Ts and the tangential glass transition temperature Tg2nd of the polyester resin are preferably both 60° C. or higher. When the softening temperature Ts and the tangential glass transition temperature Tg2nd of the polyester resin are both 60° C. or higher, the heat-resistant storage stability of the toner image can be ensured.

[0021] The weight-average molecular weight of the polyurethane elastomer is preferably 20,000 to 100,000, more preferably 20,000 to 80,000, and even more preferably 20,000 to 60,000. If the weight-average molecular weight is 20,000 or more, there is no risk of the fixed image melting when ironed, and if the weight-average molecular weight is 100,000 or less, other toner components and the binder resin can be easily melted and kneaded when forming the toner.

[0022] The content of the polyurethane elastomer is not particularly limited and can be appropriately selected depending on the purpose, but is preferably in the range of 20% by mass to 70% by mass, and more preferably in the range of 50% by mass to 60% by mass. If the content of the polyurethane elastomer is 20% by mass or more, sufficient fixability of the toner to a flexible medium such as cloth and flexibility of the toner layer after fixing can be obtained. Furthermore, if the content is 50% by mass or more, durability is further improved. If the content is 70% by mass or less, the thermal storage stability of the toner is not deteriorated and there is no risk of aggregation of toner particles occurring.

[0023] In addition, all or part of the polyurethane elastomer can be substituted with any of polyethylene terephthalate, polyethylene isophthalate, polybutylene terephthalate, polybutylene isophthalate, and styrene butadiene rubber, which have the same properties as the polyurethane elastomer.

[0024] <<Measuring method for particle size and particle size distribution based on volume percentage of toner>> The particle size distribution and particle size of the toner based on volume percentage can be measured, for example, using a particle size analyzer (Multisizer III, manufactured by Beckman Coulter) with an aperture diameter of 100 μm, and analysis can be performed using analysis software (Beckman Coulter Multisizer 3 Version 3.51). An example is shown below.

[0025] 0.5 ml of 10% by weight surfactant (alkylbenzene sulfonate, Neogen SC-A, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) was added to a 100 ml glass beaker, 0.5 g of toner was added, and the mixture was stirred with a microspatula. 80 ml of ion-exchanged water was then added to obtain a dispersion. The resulting dispersion was dispersed for 10 minutes using an ultrasonic disperser (W-113MK-II, manufactured by Honda Electronics Co., Ltd.) to obtain a toner sample dispersion. The toner sample dispersion was measured using the Multisizer III and an Isoton III (manufactured by Beckman Coulter) as the measurement solution. To ensure measurement reproducibility, the toner sample dispersion was added dropwise so that there was no error in particle size and the concentration indicated by the instrument was 8±2%, and the volume average particle size of the toner was measured.

[0026] <<Toner particle size distribution and volume average particle size>> The toner of the present invention is not particularly limited in terms of particle size distribution on a volume basis and can be appropriately selected depending on the purpose, but preferably has a peak in the range of 5 μm to 30 μm, and more preferably has a peak in the range of 10 μm to 20 μm. Here, the "peak" of the particle size distribution means that the peak top of the particle size distribution is in the above particle size range. The volume average particle size of the toner is also not particularly limited and can be appropriately selected depending on the purpose, but is preferably 5 μm to 30 μm, and more preferably 10 μm to 20 μm. For a toner as described above, the pile height of the toner layer can be increased by increasing the toner particle size, enabling easy filling of the irregularities on the surface of flexibility media such as cloth fabrics. Therefore, it is excellent in concealability and suitable. Also, considering the trade-off with transferability, as the toner, a toner having a particle size distribution with a peak in the range of 10 μm or more and 20 μm or less in terms of volume% based particle size distribution is more preferable. For the same reason, a toner having a volume average particle size of 10 μm or more and 20 μm or less is more preferable.

[0027] <<Confirmation and Quantification of the Presence of Resin in the Toner>> Regarding the resin contained in the toner of the present invention, the presence can be confirmed and quantified preferably by gas chromatograph mass spectrometer (GC-MS) or NMR (Nuclear Magnetic Resonance). Specifically, it can be performed according to the following procedures, apparatus, and conditions.

[0028] <<Component Analysis by GC-MS>> - Sample Preparation - Disperse the toner in chloroform and stir it overnight to obtain a dispersion. Subsequently, centrifuge this dispersion and collect only the supernatant. The evaporated residue of the collected supernatant is subjected to composition analysis by gas chromatograph mass spectrometer (GC-MS). An example of the measurement conditions by GC-MS is shown below. Note that a mixture obtained by dropping approximately 1 μL of a methylating agent (tetramethylammonium hydroxide 20% methanol solution: TMAH) onto a sample of about 1 mg is used as the sample.

[0029] - Measurement Conditions - · Thermal decomposition - Gas chromatograph mass spectrometry (Py-GCMS) analyzer: QP2010 (manufactured by Shimadzu Corporation) · Heating furnace: Py2020D (manufactured by Frontier Lab Co., Ltd.) · Heating temperature: 320 °C · Column: Ultra ALLOY-5 (L = 30 m, I.D = 0.25 mm, Film = 0.25 μm, manufactured by GL Sciences Inc.) · Column temperature: 50 °C (holding time: 1 minute) ~ temperature increase (10 °C / min) ~ 340 °C (holding time: 7 minutes) · Split ratio: 1:100 · Column flow rate: 1.0 ml / min · Ionization method: EI method (70 eV) · Measurement mode: Scan mode · Data for search: NIST 20 MASS SPECTRAL LIB.

[0030] <<Component analysis by NMR>> - Sample preparation - Disperse the toner in chloroform and stir it for a whole day and night to obtain a dispersion. Subsequently, centrifuge this dispersion and collect only the supernatant. The collected supernatant is evaporated to dryness and used as 1 a sample for 1H-NMR and 13 a sample for 13C-NMR, and perform composition analysis by NMR. 1 A method for preparing a sample for 1H-NMR 13 A method for preparing a sample for 13C-NMR, and an example of measurement conditions are shown below.

[0031] (1) 1 Method for preparing a sample for 1H-NMR Add 1 mL of d8-toluene (manufactured by FUJIFILM Wako Pure Chemical Corporation) to 100 mg of the sample, warm it with a dryer to dissolve it, and 1 prepare a sample for 1H-NMR. (2) 13 Method for preparing a sample for 13C-NMR Add 1 mL of deuterated 1,2-dichlorotoluene (manufactured by FUJIFILM Wako Pure Chemical Corporation) to 100 mg of the sample, warm it with a dryer to dissolve it, and 13 prepare a sample for 13C-NMR.

[0032] - Measurement conditions - · NMR apparatus: ECX-500 (manufactured by JEOL Ltd.) Measurement nucleus = 1H (500MHz), Measurement pulse file = single pulse dec.jxp (1H), 45℃ pulse, 20,000 accumulations, Relaxation Delay - 4 seconds, Data points 32K, Offset 100ppm, Observation width = 250ppm, Measurement temperature 70℃ Measurement nucleus = 13C (125MHz), measurement pulse file = single pulse dec.jxp(13C), 45℃ pulse, 64 accumulations, Relaxation Delay 5 seconds, 32K data points, observation width = 15ppm, measurement temperature 65℃

[0033] <<Weight average molecular weight measurement>> The weight average molecular weight of the resin used in the toner can be obtained by measuring the molecular weight distribution of the THF (tetrahydrofuran) soluble portion using a gel permeation chromatography (GPC) measuring device. The GPC measuring device is not particularly limited and can be appropriately selected depending on the purpose. For example, a product name such as GPC-150C (manufactured by Waters Corporation) can be used.

[0034] The column used for measuring the weight-average molecular weight is not particularly limited and can be appropriately selected depending on the purpose. Examples of the column include, by trade name, KF801 (organic solvent SEC (GPC) column), KF802 (organic solvent SEC (GPC) column), KF803 (organic solvent SEC (GPC) column), KF804 (organic solvent SEC (GPC) column), KF805 (organic solvent SEC (GPC) column), KF806 (organic solvent SEC (GPC) column), and KF807 (organic solvent SEC (GPC) column) (all manufactured by Showa Denko K.K.).

[0035] The method for measuring the weight average molecular weight of the resin used in the toner is not particularly limited and can be appropriately selected depending on the purpose. For example, the method can be as follows. The column is stabilized in a heat chamber at 40°C, and THF is passed through the column at a flow rate of 1 mL / min. Next, 0.05 g of sample is thoroughly dissolved in 5 g of THF and filtered through a pretreatment filter (e.g., Chromatodisc, 0.45 μm pore size, manufactured by Kurabo Industries, Ltd.) to adjust the final sample concentration to 0.05% to 0.6% by mass. After the sample concentration is adjusted, 50 μL to 200 μL of the THF sample solution is injected into the column. The THF-soluble fraction contained in the THF sample solution is separated, and the weight-average molecular weight (Mw) of the THF-soluble fraction in the THF sample solution is measured by converting the data into molecular weight using a detector (e.g., a differential refractive index (RI) detector (GPC-150C, manufactured by Waters Corporation)).

[0036] The weight-average molecular weight Mw and number-average molecular weight Mn of the THF-soluble fraction contained in the sample are measured by calculating the molecular weight distribution of the sample from the relationship between the logarithm of the calibration curve prepared using several monodisperse polystyrene standard samples and the count number. The standard polystyrene sample for preparing the calibration curve is, for example, a polystyrene having a molecular weight of 6×10 manufactured by Pressure Chemical Co. or Toyo Soda Kogyo Co., Ltd. 2 , 2.1×10 2 , 4×10 2 , 1.75×10 4 , 5.1×10 4 , 1.1×10 5 , 3.9 × 10 5 , 8.6×10 5 , 2 × 10 6 , and 4.48 × 10 6 It is preferable to use at least about 10 standard polystyrene samples. It is also preferable to use an RI (refractive index) detector as the detector.

[0037] <<Method for measuring softening temperature Ts>> The softening temperature of the toner of the present invention can be measured using, for example, a flow tester (CFT-500D, manufactured by Shimadzu Corporation). For example, each toner is press-formed into a tablet at the lowest pressure possible for tablet formation to form a pellet, and the pellet is stored in an 80°C thermostatic chamber for 30 minutes. Then, the pellet is naturally cooled to room temperature, and the flow tester softening temperature (Ts) and flow start temperature (Tfb) can be measured using this as a toner sample. The flow tester softening temperature (Ts) and flow start temperature (Tfb) of the toner can be determined from a flow curve measured using, for example, an elevated flow tester CFT500 (manufactured by Shimadzu Corporation), and can be measured, for example, under the following measurement conditions:

[0038] Sample amount: 1.00±0.05g Starting temperature 40℃ Achieved temperature 200℃ Heating rate: 3.0℃ / min Test load: 22.5kgf Die hole diameter 0.5mm Die length 1.0mm

[0039] 5 is a schematic diagram of a flow curve when an example of a toner according to one embodiment of the present invention is measured using an elevated flow tester, where Ts represents the softening temperature and Tfb represents the flow initiation temperature. In addition, when the toner of the present invention is measured using a flow tester, if a shoulder corresponding to Ts does not appear on the piston stroke curve, Ts cannot be automatically detected in the software attached to the flow tester, and in this case, Ts can be set to less than 40°C.

[0040] <<Measuring method for tangent glass transition temperature Tg2nd>> The melting point and glass transition temperature (Tg) of the toner of the present invention can be measured, for example, using a DSC system (differential scanning calorimeter) ("Q-200", manufactured by TA Instruments). Specifically, the melting point and glass transition temperature of a sample can be measured, for example, by the following procedure. First, approximately 5.0 mg of the target sample was placed in an aluminum sample container, which was then placed on a holder unit and placed in an electric furnace. Next, under a nitrogen atmosphere, the sample was heated from -50°C to 150°C at a heating rate of 10°C / min (first heating). The sample was then cooled from 150°C to -50°C at a cooling rate of 10°C / min, and further heated to 150°C at a heating rate of 10°C / min (second heating). During both the first and second heating, DSC curves were measured using a differential scanning calorimeter (TA Instruments, model Q-200). From the obtained DSC curves, the DSC curve at the second heating time is selected using the analysis program in the Q-200 system, and the tangent glass transition temperature Tg2nd of the target sample at the second heating time can be determined.

[0041] <Release agent> In the toner of the present invention, the type of release agent (wax type) that can be used is not particularly limited and can be appropriately selected depending on the purpose. One type may be used alone, or two or more types may be used in combination. The release agent that can be used in the present invention is not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include liquid paraffin, microcrystalline wax, natural paraffin, synthetic paraffin, polyolefin wax, and partial oxides thereof, or aliphatic hydrocarbons such as fluorides and chlorides, animal oils such as beef tallow and fish oil, vegetable oils such as coconut oil, soybean oil, rapeseed oil, rice bran wax, and carnauba wax, higher aliphatic alcohols or higher fatty acids such as montan wax, fatty acid amides, fatty acid bisamides, metal soaps such as zinc stearate, calcium stearate, magnesium stearate, aluminum stearate, zinc oleate, zinc palmitate, magnesium palmitate, zinc myristate, zinc laurate, and zinc behenate, fatty acid esters, and polyvinylidene fluoride. Among these, it is preferable to contain at least an ester wax such as a fatty acid ester.

[0042] When a maleic acid-modified polyolefin having a polypropylene block in the main chain is contained in a toner, if the content is high, the toner cannot be separated from the fixing roller (or fixing belt) during fixing, resulting in waste paper jams. However, this problem can be prevented by adding an ester wax as a release agent. Furthermore, maleic acid-modified polyolefin having a polypropylene block in the main chain can finely disperse the ester wax.

[0043] The content of the release agent in the toner is not particularly limited and can be selected appropriately depending on the purpose, but is preferably 0.1% by mass to 8.0% by mass, and more preferably 1.0% by mass to 6.0% by mass. If the content is 0.1% by mass or more, the toner and the fixing roller (or fixing belt) separate during fixing, preventing waste paper jams. Also, if the content is 8.0% by mass or less, the toner can be sufficiently fixed to the plastic film.

[0044] The toner of the present invention preferably contains a wax dispersant. The dispersant is preferably a copolymer composition containing at least styrene, butyl acrylate, and acrylonitrile as monomers, or a polyethylene adduct of the copolymer composition. The content of the wax dispersant is preferably 7 parts by mass or less per 100 parts by mass of the toner.

[0045] <Antifoaming agent> The toner of the present invention may contain an antifoaming agent. Examples of the antifoaming agent include a benzoin compound, an amide wax, a polyethylene wax, and a polypropylene wax. Among these, it is preferable to contain a benzoin compound, and it is more preferable to contain benzoin. The content of the antifoaming agent in the toner is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 0.1% by mass or more and less than 2.0% by mass, and more preferably 0.2% by mass or more and less than 1.0% by mass. If the content is less than 2.0% by mass, the toner will not discolor, and if it is 0.1% by mass or more, the effect of adding the antifoaming agent will be fully exhibited.

[0046] <Charge control agent> The toner of the present invention may contain a charge control agent. The charge control agent is not particularly limited and can be appropriately selected depending on the purpose. Examples include nigrosine and modified compounds such as fatty acid metal salts, onium salts such as phosphonium salts and their lake pigments, triphenylmethane dyes and their lake pigments, metal salts of higher fatty acids, diorganotin oxides such as dibutyltin oxide, dioctyltin oxide, and dicyclohexyltin oxide, diorganotinborates such as dibutyltin borate, dioctyltin borate, and dicyclohexyltin borate, organometallic complexes, chelate compounds, monoazometal complexes, acetylacetone metal complexes, aromatic hydroxycarboxylic acids, metal complexes of aromatic dicarboxylic acids, and quaternary ammonium salts. Other examples include aromatic hydroxycarboxylic acids, aromatic mono- and polycarboxylic acids and their metal salts, anhydrides, esters, and phenol derivatives such as bisphenols. These may be used alone or in combination of two or more.

[0047] When these charge control agents are added internally to the toner for electrophotographic development, the content is not particularly limited and can be set appropriately depending on the purpose, but it is preferable to add 0.1% by mass to 10% by mass of the total amount of the binder resin. In addition, since the charge control agent may cause coloring, it is preferable to select one that is as transparent as possible, except for black toner.

[0048] <Coloring agent> The colorant used in the toner of the present invention is not particularly limited, and a commonly used colorant can be appropriately selected and used, for example, a black toner, a cyan toner, a magenta toner, a yellow toner, a white pigment, a green toner, a blue toner, etc.

[0049] The black toner is not particularly limited and can be appropriately selected depending on the purpose, but carbon black alone or a mixture of carbon black as the main component and copper phthalocyanine or the like with the hue and brightness adjusted is preferred.

[0050] The cyan toner is not particularly limited and can be appropriately selected depending on the purpose, but copper phthalocyanine, which is pigment blue 15:3, or a mixture of the above colorant and aluminum phthalocyanine is preferred.

[0051] The magenta toner is not particularly limited and can be appropriately selected depending on the purpose, but Pigment Red 53:1, Pigment Red 81, Pigment Red 122, and Pigment Red 269 can be used alone or in combination.

[0052] The yellow toner is not particularly limited and can be appropriately selected depending on the purpose, but Pigment Yellow 74, Pigment Yellow 155, Pigment Yellow 180, and Pigment Yellow 185 can be used alone or in combination. It is preferable to use Pigment Yellow 185 alone or in combination with Pigment Yellow 74 in terms of saturation and storage stability.

[0053] The white pigment is not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include titanium dioxide that has been surface-treated with silicon, zirconia, aluminum, polyol, etc. There are no particular limitations on the green toner, and it can be selected appropriately depending on the purpose. For example, Pigment Green 7 can be used, but safety considerations must be taken into account. The blue toner is not particularly limited and can be appropriately selected depending on the purpose. Examples thereof include Pigment Blue 15:1 and Pigment Violet 23.

[0054] Furthermore, when the toner of the present invention is used as a base layer (the layer on which an image is formed closest to the release support or the recording medium), by forming a conventional toner layer on top of it, the conventional toner can also be fixed well on a cloth medium with many uneven fibers.

[0055] Furthermore, since the toner of the present invention has rubber elasticity, a printed image is less likely to crack when pulled, bent, or washed. From this viewpoint and from the viewpoint of not impairing the color of the toner to be overlaid, when the toner of the present invention is used as an underlayer, it is preferable that the colorant contained in the toner is white and / or colorless (no colorant is contained).

[0056] <External additives> The toner of the present invention may contain inorganic fine particles as an external additive. The inorganic fine particles to be added externally to the toner of the present invention are not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include silica, alumina, titanium oxide, barium titanate, magnesium titanate, calcium titanate, strontium titanate, zinc oxide, silica sand, clay, mica, wollastonite, diatomaceous earth, chromium oxide, cerium oxide, red iron oxide, antimony trioxide, magnesium oxide, zirconium oxide, barium sulfate, barium carbonate, calcium carbonate, silicon carbide, silicon nitride, etc. Among these, silica, alumina, and titanium oxide are preferred.

[0057] In addition, inorganic fine particles can be used that are surface-treated with hydrophobic treatment agent.Hydrophobic treatment agent is not particularly limited, and can be appropriately selected according to purpose, for example, silane coupling agent, silylating agent, silane coupling agent with fluorinated alkyl group, organic titanate coupling agent, aluminum coupling agent, etc. can be listed as preferred surface treatment agent.In addition, silicone oil can also be used as hydrophobic treatment agent, and sufficient effect can be obtained.

[0058] The average diameter of the primary particles of the inorganic fine particles is not particularly limited and can be selected appropriately depending on the purpose, but is preferably 5 nm to 500 nm, more preferably 5 nm to 200 nm. If it is 5 nm or more, aggregation of the inorganic fine particles is suppressed, and the inorganic fine particles can be uniformly dispersed in the toner. If it is 500 nm or less, the heat-resistant storage stability can be improved due to the filler effect. The average particle diameter here refers to a value obtained by directly determining the particle diameter from photographs obtained by a transmission electron microscope, and it is preferable to observe at least 100 particles and use the average value of the major axes.

[0059] <Developer> The toner of the present invention can be mixed with a carrier or the like and used as a developer. In other words, the developer contains the toner according to one embodiment of the present invention and may contain other components, such as a carrier, that are appropriately selected as necessary. By using this developer, a base layer with excellent fixability can be formed on the surface of fabric.

[0060] The developer may be a one-component developer or a two-component developer, but when used in a high-speed printer or the like that corresponds to the recent improvement in information processing speed, a two-component developer is preferable from the viewpoint of improving the developer life.

[0061] When the toner according to one embodiment of the present invention is used as a one-component developer, even if the toner is balanced, there is little fluctuation in the particle size of the toner, there is little toner filming on the developing roller, and there is little toner fusion to components such as blades that thin the toner layer, and good and stable developability and images can be obtained even with long-term stirring in the developing device.

[0062] The toner according to one embodiment of the present invention can be mixed with a carrier to form a two-component developer, which can be used in a two-component development electrophotographic image forming method. When the toner according to one embodiment of the present invention is used as a two-component developer, even if the toner is balanced over a long period of time, there is little fluctuation in the particle size of the toner, and good and stable developability and images can be obtained even with long-term stirring in a developing device.

[0063] <Magnetic materials> When a two-component development method is used, the magnetic fine particles used in the magnetic carrier are not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include iron powder, magnetite, spinel ferrite such as gamma iron oxide, spinel ferrite containing one or more metals other than iron (Mn, Ni, Zn, Mg, Cu, etc.), magnetoplumbite ferrite such as barium ferrite, iron or alloy particles having an oxide layer on the surface, etc. Among these, white particles are preferred in terms of color tone. The shape of the magnetic fine particles may be any of granular, spherical, and needle-like. In particular, when high magnetization is required for the magnetic carrier, it is preferable to use ferromagnetic fine particles such as iron.

[0064] In addition, in consideration of chemical stability, it is preferable to use magnetite, spinel ferrite containing gamma iron oxide, or magnetoplumbite ferrite such as barium ferrite. Specifically, MFL-35S, MFL-35HS (manufactured by Powder Tech Co., Ltd.), DFC-400M, DFC-410M, SM-350NV (manufactured by Dowa Iron Powder Co., Ltd.), etc.

[0065] By selecting the type and content of ferromagnetic fine particles (carrier), a resin carrier having the desired magnetization can be used. For example, the magnetic properties of the resin carrier are preferably such that the magnetization strength at 1,000 oersted is 30 emu / g or more and 150 emu / g or less. Such a resin carrier can be produced by spraying a molten mixture of magnetic fine particles and an insulating binder resin using a spray dryer, or by reacting and curing a monomer or prepolymer in an aqueous medium in the presence of magnetic fine particles, thereby producing a resin carrier in which magnetic fine particles (carrier) are dispersed in a condensation binder.

[0066] The chargeability can be controlled by adhering positively or negatively chargeable particles or conductive particles to the surface of the magnetic carrier, or by coating the surface with a resin. Examples of surface coating materials (resins) that can be used include silicone resins, acrylic resins, epoxy resins, and fluorine-based resins, and the coating can further include positively or negatively charged particles or conductive particles, but among these, silicone resins and acrylic resins are preferred. In the present invention, the mass ratio of the carrier in the developer contained in the developing device is preferably 85 mass % or more and less than 98 mass %.

[0067] When the mass ratio of the carrier in the developer is 85 mass % or more, scattering of the toner from the developing device is less likely to occur, and the occurrence of defective images can be reduced. When the mass ratio of the carrier in the developer is less than 98 mass %, it is possible to prevent the charge amount of the electrophotographic developing toner from increasing excessively and the supply amount of the electrophotographic developing toner from becoming insufficient, thereby reducing the occurrence of defective images due to a decrease in image density.

[0068] <Flow improver> The present invention may contain a flowability improver as an additive. The flowability improver is not particularly limited and can be appropriately selected depending on the purpose as long as it is capable of performing a surface treatment to increase hydrophobicity and prevent deterioration of flow properties or charging properties even under high humidity conditions. Examples of the flowability improver include silane coupling agents, silylating agents, silane coupling agents having a fluorinated alkyl group, organic titanate coupling agents, aluminum coupling agents, silicone oils, and modified silicone oils. The silica and titanium oxide used as the external additives are preferably surface-treated with such a flowability improver and used as hydrophobic silica and hydrophobic titanium oxide.

[0069] <Cleaning improver> The present invention may contain a cleaning property improver as an additive. The cleaning property improver is not particularly limited as long as it can be added to the toner according to an embodiment of the present invention to remove developer remaining on the electrostatic latent image carrier or primary transfer medium after transfer, and can be appropriately selected depending on the purpose. Examples of the cleaning property improver include fatty acid metal salts such as zinc stearate, calcium stearate, and stearic acid, and polymer fine particles produced by soap-free emulsion polymerization, such as polymethyl methacrylate fine particles and polystyrene fine particles. The polymer fine particles preferably have a relatively narrow particle size distribution, and preferably have a volume average particle size of 0.01 μm or more and 1 μm or less.

[0070] <<Toner manufacturing method>> The method for producing the toner used in the present invention is not particularly limited and can be appropriately selected depending on the purpose. An example of the method for producing the toner of the present invention will be described below. The toner of the present invention is preferably produced by a melt-kneading pulverization method.

[0071] In one embodiment, the method for producing the toner of the present invention can include a step of obtaining a binder resin mixture (mixing step), a step of obtaining a kneaded product of the mixture (melting and 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-pulverizing step), and a step of classifying and recovering the pulverized product (classification step).

[0072] -Process for obtaining a binder resin mixture (mixing process)- First, a binder resin, a release agent, and, if necessary, a colorant, a charge control agent, etc. are mixed in a mixer to obtain a mixture (mixing step). The mixer is not particularly limited and can be appropriately selected depending on the purpose. Examples include a Henschel mixer (product name: FM20B, manufactured by Nippon Coke and Engineering Co., Ltd.) and a Super Mixer (SMV-20Ba, manufactured by Kawata Corporation).

[0073] -Process for obtaining a kneaded mixture (melt-kneading process)- Next, the resulting mixture is melt-kneaded using a thermal melt kneader to obtain a kneaded product (melt-kneading step). The hot melt kneader is not particularly limited and can be appropriately selected depending on the purpose. Examples of the kneader include, by trade name, twin-screw extruder PCM series (manufactured by Ikegai Corporation), TEM-type extruder (manufactured by Shibaura Machine Co., Ltd.), twin-screw extruder PCM Co-Kneader (manufactured by Buss Co., Ltd.), and open-roll type continuous kneader Kneadex (manufactured by Nippon Coke and Engineering Co., Ltd.).

[0074] -Process for obtaining a solidified product from the kneaded material (solidification process)- Next, the obtained 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 can be appropriately selected depending on the purpose. For example, any appropriate method can be used. However, in order to efficiently pulverize the material in the subsequent pulverization step, it is preferable to reduce the material to a certain particle size in the solidification step. A suitable method is to pelletize the kneaded product in a solidification step after the kneading step. The pelletizing process includes a strand cutting method, a water-cooled hot cutting method, and an underwater cutting method. For example, in the strand cutting method, the kneaded molten material immediately after the kneading step is extruded through a die with a diameter of about 3 mm to form a strand, which is cooled in a cooling device such as a water tank, and after cooling, is cut into pellets by a pelletizer. The particle size of the pellets can be adjusted by adjusting the feed rate of the melt kneader and the feed rate of the pelletizer to adjust the strand thickness, and by adjusting the cutting width, it is possible to process the material into pellets of an appropriate particle size. The particle size of the pellets is preferably 0.5 mm to 3 mm in diameter, more preferably 1 mm to 2 mm in diameter. Even in the case of coarse particle formation before the pulverization step, the smaller the particles, the more efficient the pulverization. However, the smaller the strand diameter, the more likely the strand is to break during processing, making it difficult to maintain process stability, so processing with a diameter of 1 mm or more is preferred.

[0075] -Process for obtaining pulverized solid material (fine pulverization process)- The solid matter thus obtained is then finely pulverized to obtain a pulverized product (fine pulverization step). The solid matter can be pulverized using a known pulverization method, such as a jet mill method in which the toner is contained in a high-speed airflow and the solid matter is pulverized by the energy generated when the toner is collided with a collision plate, an inter-particle collision method in which toner particles collide with each other in an airflow, or a mechanical pulverization method in which the toner is supplied between a rotor rotating at high speed and a narrow gap to be pulverized.

[0076] It is preferred to use a cryogenic grinding method to grind the toner of the present invention. Some materials have the property of becoming suddenly brittle below a certain temperature, known as "low-temperature brittleness." By utilizing this property, it is possible to crush rubber and plastics, which are difficult to crush at room temperature. "Low-temperature crushing," which utilizes the extremely low temperature of liquid nitrogen at -196°C, is also called "freeze crushing" or "frozen grinding." By using the freeze-pulverization method, the pulverization property is significantly improved, and the shape of the pulverized particles is stabilized, making it possible to obtain a finely pulverized product more suitable for toner.

[0077] In this freeze-pulverization, it is preferable to use the mechanical pulverization method in which the toner is supplied between the rotor rotated at high speed and a narrow gap to be pulverized. Specifically, the coarsely granulated kneaded material is placed in a cooler, cooled with liquid nitrogen, processed in a grinder, and sieved to obtain particles of a target particle size or smaller. The coarse particles remaining on the sieve are returned to the cooler and crushed again.

[0078] As a cooling means, a cooling machine such as a chiller can be used. The product temperature of the coarse particles to be finely pulverized is "not more than the glass transition point Tg of the coarse particles - 5°C", more preferably "not more than the glass transition point Tg of the coarse particles - 20°C".

[0079] -The process of classifying and recovering the crushed material (classification process)- The pulverized material is then classified to recover pulverized material having a predetermined volume average particle size, thereby obtaining a toner (classification step). There are no particular limitations on the classification method, and an airflow method, a rotary rotor method, or the like can be appropriately selected depending on the purpose. Examples of airflow classifiers include an elbow jet classifier (manufactured by Matsubo Corporation), and examples of rotary rotor classifiers include a TSP separator and a TTSP separator (manufactured by Hosokawa Micron Corporation).

[0080] The toner according to one embodiment of the present invention can also be produced using a solution suspension method. When producing the toner using the solution suspension method, an oil phase in which toner materials such as a binder resin, a release agent, and optionally a colorant and a charge control agent are dissolved or dispersed in an organic solvent is dispersed in an aqueous medium (aqueous phase), and the binder resin is reacted. This produces a dispersion containing a dispersion (oil droplets) containing a prepolymer in which the toner materials are emulsified or dispersed. The organic solvent is then removed from the dispersion, and the resulting mixture is filtered, washed, dried, and further classified as necessary to produce toner base particles. The toner according to one embodiment of the present invention can be obtained by granulating the base particles obtained using the solution suspension method.

[0081] The organic solvent is not particularly limited and can be appropriately selected depending on the purpose, but an organic solvent having a boiling point of less than 150° C. is preferred in terms of ease of removal. The organic solvent having a boiling point of less than 150° C. is not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include toluene, xylene, benzene, carbon tetrachloride, methylene chloride, 1,2-dichloroethane, 1,1,2-trichloroethane, trichloroethylene, chloroform, monochlorobenzene, dichloroethylidene, methyl acetate, ethyl acetate, methyl ethyl ketone, methyl isobutyl ketone, etc. These may be used alone or in combination of two or more. Of these, ethyl acetate, toluene, xylene, benzene, methylene chloride, 1,2-dichloroethane, chloroform, and carbon tetrachloride are preferred, and ethyl acetate is more preferred.

[0082] The aqueous medium is not particularly limited and can be appropriately selected depending on the purpose. Examples include water, a solvent miscible with water, and a mixture thereof. These may be used alone or in combination of two or more. Among these, water is preferred. The water-miscible solvent is not particularly limited and can be appropriately selected depending on the purpose. Examples thereof include alcohols, lower ketones, dimethylformamide, tetrahydrofuran, and cellosolves. The alcohol is not particularly limited and can be appropriately selected depending on the purpose. Examples include methanol, isopropanol, and ethylene glycol. The lower ketones are not particularly limited and can be appropriately selected depending on the purpose. Examples thereof include acetone and methyl ethyl ketone.

[0083] The method for removing the organic solvent from the dispersion is not particularly limited and can be appropriately selected depending on the purpose. Examples include a method in which the temperature of the entire reaction system is gradually increased to evaporate the organic solvent in the oil droplets, and a method in which the dispersion is sprayed into a dry atmosphere to remove the organic solvent in the oil droplets. The classification in the dissolution suspension method may be carried out by removing fine particles in the liquid using a cyclone, decanter, centrifugal separation or the like, or the classification operation may be carried out after drying. In this manner, the toner base of the present invention is produced.

[0084] -Process of mixing external additives and sieving aggregates (mixing / sieving process)- To adjust the powder characteristics and charging characteristics required for the toner, fine particles (external additives) such as silicon dioxide and titanium oxide are mixed with the obtained toner base, and any aggregates that occur during mixing are sieved off and removed. As the external additive mixer, an agitator mixer is preferably used, and examples thereof include a Henschel mixer (manufactured by Mitsui Mining Co., Ltd.), a Super Mixer (manufactured by Kawata Co., Ltd.), and a TSK mixer (manufactured by Tsukishima Kikai Co., Ltd.).

[0085] (Toner set) The toner set of the present invention refers to a set including a color toner containing a binder resin and a colorant, and the toner of the present invention. The color toner is not particularly limited, and any known color toner can be selected as appropriate depending on the purpose. The binder resin contained in the color toner is not particularly limited, and can be selected as appropriate depending on the purpose, and can be, for example, the same as the binder resin contained in the toner according to one embodiment of the present invention. The colorant is not particularly limited, and any known colorant can be selected as appropriate depending on the purpose. By mounting the above toner set in an image forming apparatus described below and forming an image, an image is formed using the toner according to one embodiment of the present invention, and therefore, an image can be formed that takes advantage of the characteristics of the toner, which has excellent fixing properties to fabric.

[0086] <Transfer sheet> The transfer substrate used in the image forming method of the present invention is not limited as long as it is a sheet-like substrate that has releasability and allows the color toner layer printed on the transfer substrate and the toner layer formed by the toner of the present invention to be transferred to a transfer receiving material by heat and pressure. The transfer substrate may have a release layer, which often has poor breathability, and this can lead to problems such as air not escaping during fixing and remaining inside, causing surface defects. The transfer substrate may be a peelable support or a flexible material with a surface roughness of 1 μm or more. The color image formed on the transfer substrate is a mirror image of the original image, which is inverted left to right. After being thermally transferred onto the transfer material, it is again inverted left to right to complete the desired image. Similarly, the toner layer formed by the toner of the present invention is formed over the color image formed on the transfer substrate, and therefore forms a mirror image that is horizontally inverted with respect to the original image. The left-right reversed mirror image is formed by printing mirror image information that has been left-right reversed in advance on a PC or the like. In the case of an image forming apparatus with a scanner function, an original image may be scanned and then inverted before being output, or a mirror image that has already been inverted left to right may be scanned.

[0087] (Toner storage unit) The toner storage unit in the present invention refers to a unit having a function of storing toner and storing the toner of the present invention. The form of the toner storage unit is not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include a toner storage container, a developing unit, and a process cartridge.

[0088] The toner storage container refers to a container that stores toner. When the toner is used as a developer, the toner container may be referred to as a developer container. The developer container is not particularly limited and can be appropriately selected from known containers, and examples thereof include a container having a container body and a cap. The size, structure, material, etc. of the container body of the toner container and the developer container are not particularly limited and can be appropriately selected depending on the purpose.

[0089] The shape of the container body of the developer storage container is not particularly limited and can be appropriately selected depending on the purpose, but it is preferably cylindrical, such as cylindrical, and has a spirally formed uneven portion on the inner circumferential surface. By rotating the container body, the developer contained therein can be easily transferred to the discharge port side. Furthermore, it is more preferable that part or all of the uneven portion is formed in a bellows shape. This makes it easier for the developer to transfer to the discharge port side.

[0090] The materials for the toner storage container and the developer storage container are not particularly limited and can be appropriately selected depending on the purpose, but it is preferable that they have good dimensional accuracy, and examples of such materials include resin materials such as polyester resin, polyethylene resin, polypropylene resin, polystyrene resin, polyvinyl chloride resin, polyacrylic acid, polycarbonate resin, ABS resin, and polyacetal resin.

[0091] The toner storage container and the developer storage container are easy to store, transport, etc., and are easy to handle, so they can be detachably attached to the image forming apparatus, process cartridge, etc. described below, and used to replenish toner and developer. The developing device has a means for storing toner and developing the toner. The process cartridge is a device that integrates at least an electrostatic latent image carrier and a developing means, contains toner, and is detachably mountable to an image forming apparatus. The process cartridge may further include at least one selected from a charging means, an exposure means, a cleaning means, etc. By attaching the toner storage unit according to one embodiment of the present invention to the image forming apparatus of the present invention and forming an image, the image is formed using the toner according to one embodiment of the present invention, and therefore, it is possible to form an image using a toner that has excellent fixing properties to fabric.

[0092] (Image forming method and image forming apparatus) The image forming apparatus according to the present invention comprises an electrostatic latent image carrier, electrostatic latent image forming means for forming an electrostatic latent image on the electrostatic latent image carrier, developing means for developing the electrostatic latent image formed on the electrostatic latent image carrier with a developer containing the toner of the present invention to form a toner image, transfer means for transferring the toner image formed on the electrostatic latent image carrier onto a peelable support or a flexible recording medium having a surface roughness of 1 μm or more, and fixing means for fixing the toner image transferred onto the peelable support or the flexible recording medium, and may further comprise other means as necessary.

[0093] The image forming method of the present invention comprises an electrostatic latent image forming step of forming an electrostatic latent image on an electrostatic latent image carrier; a developing step of developing the electrostatic latent image formed on the electrostatic latent image carrier with a developer containing the toner of the present invention to form a toner image; a transfer step of transferring the toner image formed on the electrostatic latent image carrier onto a peelable support or a flexible recording medium having a surface roughness of 1 μm or more; and a fixing step of fixing the toner image transferred onto the peelable support or the flexible recording medium, wherein the toner image is formed by the toner of the present invention, and the method may comprise other steps as necessary.

[0094] The image forming method can be suitably performed by the image forming apparatus, the electrostatic latent image forming step can be suitably performed by the electrostatic latent image forming means, the developing step can be suitably performed by the developing means, the transfer step can be suitably performed by the transfer means, the fixing step can be suitably performed by the fixing means, and the other steps can be suitably performed by the other means.

[0095] <<Electrostatic latent image carrier>> The structure and size of the electrostatic latent image bearing member are not particularly limited, and may be appropriately selected from known structures depending on the purpose. The material of the electrostatic latent image carrier is not particularly limited and can be appropriately selected depending on the purpose. Examples include inorganic photoconductors such as amorphous silicon and selenium, and organic photoconductors (OPC) such as polysilane and phthalopolymethine. Examples of the organic photoreceptor include a laminated photoreceptor having a laminated structure in which a layer (charge generation layer) in which a charge generation material such as metal-free phthalocyanine or titanyl phthalocyanine is dispersed in a binder resin and a layer (charge transport layer) in which a charge transport material is dispersed in a binder resin are stacked on a support such as an aluminum drum, and a single-layer photoreceptor having a single-layer photosensitive layer in which both a charge generation material and a charge transport material are dispersed in a binder resin on a support. In the single-layer type photoreceptor, a hole transport material and an electron transport material can be added to the photosensitive layer as charge transport materials. An undercoat layer may be provided between the support and the multilayer charge generating layer or the single-layer photosensitive layer. The shape of the electrostatic latent image carrier is not particularly limited and can be appropriately selected depending on the purpose, but is preferably cylindrical. The outer diameter of the cylindrical electrostatic latent image carrier is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 3 mm to 100 mm, more preferably 5 mm to 50 mm, and even more preferably 10 mm to 30 mm.

[0096] <Electrostatic latent image forming means and electrostatic latent image forming process> The electrostatic latent image forming means in the image forming apparatus according to the present invention is not particularly limited as long as it is a means for forming an electrostatic latent image on an electrostatic latent image carrier, and can be appropriately selected depending on the purpose. The electrostatic latent image forming means may include, for example, a charging device that uniformly charges the surface of the electrostatic latent image carrier, and an exposure device that imagewise exposes the surface of the electrostatic latent image carrier.

[0097] The electrostatic latent image forming step in the image forming method of the present invention is a step of forming an electrostatic latent image on an electrostatic latent image carrier, and can include a charging step of charging the surface of the electrostatic latent image carrier, and an exposure step of exposing the charged surface of the electrostatic latent image carrier to light to form an electrostatic latent image. There are no particular limitations on the charging method, and it can be appropriately selected depending on the purpose. For example, it can be performed by applying a voltage to the surface of the electrostatic latent image bearing member using a charging device. The exposure method is not particularly limited and can be appropriately selected depending on the purpose. For example, the exposure can be carried out by exposing the surface of the electrostatic latent image bearing member to light in an imagewise manner using an exposure device. The formation of the electrostatic latent image is not particularly limited and can be appropriately selected depending on the purpose. For example, the formation can be performed by uniformly charging the surface of the electrostatic latent image carrier and then exposing it to light in an imagewise manner, and can be performed by an electrostatic latent image forming means.

[0098] -Charging device- The charging device is not particularly limited and can be appropriately selected depending on the purpose. Examples thereof include a contact charger equipped with a conductive or semiconductive roll, brush, film, rubber blade, etc., and a non-contact charger utilizing corona discharge such as a corotron or scorotron. The charging device may take any form such as a roller, a magnetic brush, a fur brush, etc., and can be selected according to the specifications or form of the image forming apparatus. The charging device is preferably one that is arranged in contact or non-contact with the electrostatic latent image carrier and charges the surface of the electrostatic latent image carrier by applying a superimposed DC and AC voltage to it, or one that is a charging roller that is arranged in close proximity to the electrostatic latent image carrier but not in contact with it via a gap tape and charges the surface of the electrostatic latent image carrier by applying a superimposed DC and AC voltage to the charging roller. The charging device is not limited to a contact-type charging device, but it is preferable to use a contact-type charging device because it allows for an image forming apparatus in which the amount of ozone generated from the charging device is reduced.

[0099] -Exposure equipment- The exposure device is not particularly limited as long as it can expose the surface of the electrostatic latent image carrier charged by the charging device in the form of an image to be formed, and can be appropriately selected depending on the purpose. Examples of the exposure device include various exposure devices such as a copying optical system, a rod lens array system, a laser optical system, and a liquid crystal shutter optical system. The light source used in the exposure device is not particularly limited and can be appropriately selected depending on the purpose. Examples include general light-emitting materials such as fluorescent lamps, tungsten lamps, halogen lamps, mercury lamps, sodium lamps, light-emitting diodes (LEDs), semiconductor lasers (LDs), and electroluminescence (EL). In order to irradiate only light in a desired wavelength range, various filters such as a sharp cut filter, a band pass filter, a near infrared cut filter, a dichroic filter, an interference filter, and a color temperature conversion filter can be used. It is also possible to employ a backlight system in which exposure is performed imagewise from the back side of the electrostatic latent image carrier.

[0100] <Developing means and developing process> The developing means in the image forming apparatus according to the present invention is not particularly limited as long as it can develop the electrostatic latent image formed on the electrostatic latent image carrier to form a toner image, and can be appropriately selected depending on the purpose. For example, the developing means can be suitably equipped with a developing unit that contains toner and can apply the toner to the electrostatic latent image in a contact or non-contact manner, and a developing unit equipped with a toner container is preferred. The developing step in the image forming method of the present invention is a step of forming a toner image by sequentially developing an electrostatic latent image with toners of multiple colors. The toner image can be formed, for example, by developing the electrostatic latent image with the toners, using a developing device. In the developing means and developing step, the toner according to one embodiment of the present invention is used. Preferably, a toner image may be formed by using a developer containing the toner according to one embodiment of the present invention and, if necessary, other components such as a carrier.

[0101] The developing device may be a single-color developing device or a multi-color developing device, and is preferably a developing device having, for example, an agitator that charges the toner by friction agitation, a magnetic field generating unit fixed inside, and a rotatable developer carrier that carries developer containing toner on its surface. In the developing unit, for example, toner and carrier are mixed and stirred, and the toner is charged by friction during this process and held in a standing state on the surface of the rotating magnet roller, forming a magnetic brush. Because the magnet roller is located near an electrostatic latent image carrier, some of the toner constituting the magnetic brush formed on the surface of the magnet roller moves to the surface of the electrostatic latent image carrier by electrical attraction. As a result, the electrostatic latent image is developed with toner, and a toner image made of toner is formed on the surface of the electrostatic latent image carrier.

[0102] The image forming apparatus according to the present invention may be equipped with a total of five developing units, including developing units for color toners (black, cyan, magenta, and yellow) and a developing unit for the toner of the present invention. The toner of the present invention may be of any color, but is preferably colorless or white. The toner used in the developing units may be a toner according to one embodiment of the present invention, partially or entirely, of the black, cyan, magenta, and yellow color toners.

[0103] <Transfer means and transfer process> The transfer means in the image forming apparatus according to the present invention preferably has a first transfer section that transfers a toner image onto an intermediate transfer body to form a composite transfer image, and a second transfer section that transfers the composite transfer image onto the peeling support or the flexible recording medium. The intermediate transfer body is not particularly limited and can be appropriately selected from known transfer bodies depending on the purpose, and a transfer belt is a suitable example.

[0104] The transfer step in the image forming apparatus of the present invention is a step of transferring a toner image onto the peelable support or the flexible recording medium. The transfer step preferably uses an intermediate transfer body, and after the toner image is primarily transferred onto the intermediate transfer body, the toner image is secondarily transferred onto the peelable support or the flexible recording medium.

[0105] It is more preferable that the transfer step includes a first transfer step in which toner of two or more colors, preferably full-color toner, is used to transfer a toner image onto an intermediate transfer body to form a composite transfer image, and a second transfer step in which the composite transfer image is transferred onto the peelable support or the flexible recording medium. The transfer can be carried out by, for example, charging the electrostatic latent image carrier with the toner image using a transfer charging device, and can be carried out by the transfer means.

[0106] The transfer means (first transfer section and second transfer section) preferably has at least a transfer device that peels and charges the toner image formed on the electrostatic latent image carrier onto the peeling support side or the flexible recording medium side. The number of the transfer means may be one or more. Examples of the transfer means include a corona transfer device using corona discharge, a transfer belt, a transfer roller, a pressure transfer roller, and an adhesive transfer device.

[0107] The release support is typically release paper, but is not particularly limited as long as it is capable of transferring the unfixed image after development, and can be selected appropriately depending on the purpose. Plain paper or a PET base for an OHP can also be used. The flexible recording medium having a surface roughness of 1 μm or more is typically a cloth, but is not particularly limited as long as it is capable of transferring an unfixed image after development, and can be appropriately selected depending on the purpose. Examples include woven fabrics made of fibers and nonwoven fabrics.

[0108] <Fixing means and fixing process> The fixing means in the image forming apparatus according to the present invention is not particularly limited and can be appropriately selected depending on the purpose, but a known heating and pressurizing unit is preferred. Examples of the heating and pressurizing unit include a combination of a heating roller and a pressure roller, and a combination of a heating roller, a pressure roller and an endless belt.

[0109] The fixing process in the image forming apparatus of the present invention is a process of fixing the toner image transferred onto the peelable support or the flexible recording medium using a fixing device, and may be performed for each color developer each time it is transferred onto the peelable support or the flexible recording medium, or may be performed simultaneously for each color developer in a stacked state.

[0110] The fixing means is preferably a heating and pressurizing section that has a heating element having a heat generating element, paper or release paper that contacts the heating element, and a pressure member that presses against the heating element via the paper or release paper, and that can heat and fix the peelable support or flexible recording medium on which an unfixed image has been formed by passing the film between the film and the pressure member.

[0111] The heating temperature in the heating and pressurizing section is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 80°C to 200°C. The surface pressure in the heating and pressing section is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 10 N / cm 2 More than 80N / cm 2 It is preferable that: In this embodiment, a fixing means such as a known optical fixing device may be used together with or instead of the fixing means depending on the purpose.

[0112] <Other means and other steps> In addition to the above-mentioned configuration, the image forming apparatus according to the present invention may be provided with other means appropriately selected as required, such as a discharging means, a cleaning means, a recycling means, a control means, and the like. In addition to the above-described configuration, the image forming method of the present invention may include other steps appropriately selected as necessary, such as a charge eliminating step, a cleaning step, and a recycling step.

[0113] <Static Removal Means and Static Removal Process> The discharging means is not particularly limited as long as it can apply a discharging bias to the electrostatic latent image bearing member, and can be appropriately selected from known discharging means depending on the purpose. For example, a discharging lamp is preferably used. The charge removal step is a step of removing electricity by applying a charge removal bias to the electrostatic latent image bearing member, and can be suitably performed by the charge removal unit.

[0114] <Cleaning means and cleaning process> The cleaning means is not particularly limited as long as it can remove toner remaining on the electrostatic latent image carrier, and can be appropriately selected from known cleaners depending on the purpose. Examples include magnetic brush cleaners, electrostatic brush cleaners, magnetic roller cleaners, blade cleaners, brush cleaners, and web cleaners. The cleaning step is a step of removing the toner remaining on the electrostatic latent image bearing member, and can be suitably carried out by the cleaning means. The image forming apparatus according to the present invention can improve cleaning performance by including the cleaning means. Specifically, by controlling the inter-toner adhesion, the fluidity of the toner can be controlled, improving cleaning performance. Furthermore, by controlling the properties of the deteriorated toner, excellent cleaning quality can be maintained even over a long service life or under harsh conditions such as high temperature and humidity. Furthermore, since the external additives can be sufficiently released from the toner on the electrostatic latent image carrier, a deposition layer (dam layer) of the external additives can be formed in the cleaning blade nip, thereby achieving high cleaning performance.

[0115] <Recycling methods and processes> The recycling means is not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include known transport means. The recycling step is a step of recycling the toner removed in the cleaning step into the developing means, and can be suitably carried out by the recycling means.

[0116] <Control means> The control means can control the movement of each of the above-mentioned parts. The control means is not particularly limited as long as it can control the movement of each of the above-mentioned parts, and can be appropriately selected depending on the purpose. Examples of the control means include control devices such as a sequencer and a computer.

[0117] The image forming apparatus of the present invention can form images using a toner according to one embodiment of the present invention, and can therefore provide images with excellent fixability on flexible media such as cloth, while also reducing power consumption and stably providing high-quality images. The image forming method of the present invention can form an image using the toner according to one embodiment of the present invention, and therefore can provide an image that has excellent fixing properties on a flexible medium such as cloth, and can also stably provide high-quality images. Here, one embodiment of the image forming apparatus of the present invention will be described with reference to Fig. 1. However, the present invention is not limited to this embodiment in any way. In each drawing, the same components are denoted by the same reference numerals, and redundant explanations may be omitted. Furthermore, the number, position, shape, etc. of the following components are not limited to this embodiment, and may be any number, position, shape, etc. that is preferable for implementing the present invention.

[0118] FIG. 1 is a schematic diagram showing an example of an image forming apparatus according to an embodiment of the present invention.

[0119] 1 is a so-called tandem image forming apparatus in which five toner developing units 35, 36, 37, 38, and 39 for yellow, cyan, magenta, black, and white toners are arranged in parallel, and a full-color image is formed by superimposing the toner images of yellow (Y), cyan (C), magenta (M), black (K), and white (A) formed by each toner developing unit. There are no particular restrictions on the arrangement of the toner image forming units for each color. Each toner developing unit 35, 36, 37, 38, 39 is provided with a photoconductor 5, 11, 17, 23, 29 that is rotated and driven as an electrostatic latent image carrier. Also, an exposure device is provided that exposes each photoconductor 5, 11, 17, 23, 29 to laser light or LED light based on image information for each color to form a latent image, and irradiates the photoconductor with exposure light 7, 13, 19, 25, 31.

[0120] An intermediate transfer belt 40 serving as an intermediate transfer body is disposed so as to be movable on its surface, facing each of the toner developing units 35, 36, 37, 38, and 39. Primary transfer devices 10, 16, 22, 28, and 34 are disposed opposite the photoconductors 5, 11, 17, 23, and 29 via the intermediate transfer belt 40, and transfer the toner images of each color formed on the photoconductors 5, 11, 17, 23, and 29 onto the intermediate transfer belt 40.

[0121] Around the photosensitive members 5, 11, 17, 23, and 29, which are electrostatic latent image carriers, there are provided chargers 6, 12, 18, 24, and 30, which are charging devices; developing means 8, 14, 20, 26, and 32; primary transfer devices 10, 16, 22, 28, and 34, which are transfer means; and cleaning devices 9, 15, 21, 27, and 33.

[0122] In this embodiment, an elastic intermediate transfer belt can also be used as the intermediate transfer belt 40. As the elastic intermediate transfer belt, for example, one in which a flexible elastic layer is laminated on a rigid base layer that is relatively flexible can be used. In order to prevent the intermediate transfer belt 40 from meandering, a guide member for preventing deviation may be provided on the inner peripheral surface of the intermediate transfer belt 40 .

[0123] The primary transfer devices 10, 16, 22, 28, and 34 sequentially transfer the respective color toner images formed by the respective toner developing units 35, 36, 37, 38, and 39, which will be described later, onto the intermediate transfer belt 40, and superimpose the images to form a full-color image. Further, downstream of the primary transfer devices 10, 16, 22, 28, and 34 in the surface movement direction of the intermediate transfer belt 40, a secondary transfer device 65 that transfers the toner images on the intermediate transfer belt 40 to a transfer medium in one go is disposed. Furthermore, downstream of the secondary transfer device 65, a belt cleaning device 47 is provided to remove toner remaining on the surface of the intermediate transfer belt 40. It is also possible to provide a collecting means for receiving the toner etc. removed by the belt cleaning device 47. A dish-shaped tray or the like can be used as the collecting means.

[0124] A paper feed unit 1 equipped with a paper feed roller 2 is provided at the bottom of the image forming apparatus, and feeds the transfer medium toward registration rollers 73. Registration rollers 3 and 4 feed the transfer medium toward the opposing portion of intermediate transfer belt 40 and secondary transfer device 41 in accordance with the timing of the toner image formation. The full-color toner image on intermediate transfer belt 40 is transferred onto the transfer medium by secondary transfer device 41, fixed by fixing device 43, and then discharged outside the apparatus.

[0125] Next, we will explain each of the toner developing units 35, 36, 37, 38, and 39. The toner developing units 35, 36, 37, 38, and 39 are almost identical in configuration and operation except for the color of toner they contain, so the following explanation will focus on the configuration and operation of the toner developing units.

[0126] FIG. 2 is a schematic diagram showing a configuration of a main part of an example of an image forming apparatus according to an embodiment of the present invention. Around the photosensitive drum 51 of the toner developing unit 50, various means for performing the electrophotographic process, such as a charging device 54, a developing device 52, and a cleaning device 53, are arranged, and by known operations, toner images of various colors are formed on the photosensitive drum 51, which is an electrostatic latent image carrier. Such a toner developing unit 50 may be formed integrally as a process cartridge that is detachable from the main body of the image forming apparatus.

[0127] The developing units for each color include the photoconductor, the charger, the developing means, the cleaning device, etc. Yellow toner developing unit 35, magenta toner developing unit 36, cyan toner developing unit 37, black toner developing unit 38, and toner developing unit 39 of the present invention each form an image, which is then transferred to intermediate transfer belt 40. The image formed on intermediate transfer belt 40 is transferred to a transfer medium by secondary transfer device 41 and fixed by fixing device 43. A paper feed cassette 1 and a paper feed roller 2 are provided below the developing units, which feed the transfer medium toward registration rollers 3 and 4. Registration rollers 3 and 4 feed the transfer medium toward the opposing portion of intermediate transfer belt 40 and secondary transfer device 41 in synchronization with the formation of the toner image. It is also preferable that the toner image of the present invention is formed closest to the transfer medium. The transfer medium is preferably a peelable support and may be a flexible recording medium. [Example]

[0128] The present invention will be described in more detail below with reference to examples and comparative examples, but the present invention is not limited thereto. In the following description, "parts" means "parts by mass" and "%" means "% by mass" unless otherwise specified. (Toner production) [Toner 1 manufacturing example] -Raw materials for Toner 1- Polyurethane elastomer ECOFREEN POWDER 50% (Made by ECOFREEN, softening point 120℃, glass transition temperature -29℃) Polyester resin RN-306SF 20% (Kao Corporation, softening temperature 100°C, glass transition temperature 60°C) Wax dispersant (EXD-001, manufactured by Sanyo Chemical Co., Ltd.) 2.5% Ester wax (LW-13, manufactured by Sanyo Chemical Industries, Ltd.) 2.5% Titanium dioxide white pigment (PF-739, manufactured by Ishihara Sangyo Co., Ltd.) 25% Benzoin 0.5%

[0129] The above raw materials for Toner 1 were premixed using a Henschel mixer (FM20B, manufactured by Nippon Coke and Engineering Co., Ltd.), and then melted and kneaded in a batch kneader (Wonder Kneader "WDS7-30", manufactured by Moriyama Corporation) at a temperature set to 90°C. The resulting kneaded material was extruded through a 3 mm diameter die using a feeder ruder to form strands, which were cooled in a water bath with a water temperature of 15°C or less and solidified. The strands were then cut using a pelletizer to obtain Toner pellets 1 with a diameter of 2 mm and a length of 2 mm. The pellets are the roughly crushed melted and kneaded toner components.

[0130] The pellets were then placed in a cooler, cooled with liquid nitrogen, and pulverized in a mechanical pulverizer (Rinrex Mill LX, manufactured by Hosokawa Micron Corp.) The pulverized material discharged from the pulverizer was sieved through a 25 mesh screen, and the unsuccessful sieve was reintroduced into the pulverizer to obtain fine particles that passed through the 25 mesh screen. The 25-mesh passing fine particles were returned to room temperature and then finely classified using an air classifier (Matsubo Corporation, EJ-LABO) while appropriately adjusting the louver opening so that particles of 5 μm or less constituted 10% or less by number, thereby obtaining toner base particles with a volume average particle size of 18 μm. Next, 1.0 part of Additive 1 (HDK-2000, manufactured by Clariant Co., Ltd., substance name: silica) and 1.0 part of Additive 2 (H05TD, manufactured by Clariant Co., Ltd., substance name: silica) were mixed with 100 parts of the obtained toner base particles in a Henschel mixer to prepare [Toner 1].

[0131] Examples 2 to 4 [Toner 2], [Toner 3] and [Toner 4] of Examples 2 to 4 were obtained in the same manner as in Example 1, except that the toner composition in Example 1 was changed to the composition shown in Table 1.

[0132] (Comparative Examples 1 to 3) [Toner 5], [Toner 6] and [Toner 7] of Comparative Examples 1 to 3 were obtained in the same manner as in Example 1, except that the toner composition in Example 1 was changed to the composition shown in Table 1.

[0133] (Toner characteristics) <Measurement of toner softening temperature Ts> The softening temperature of [Toner 1] was measured using a flow tester (Shimadzu Corporation, CFT-500D). [Toner 1] was pressed into tablets at the minimum pressure possible for tablet formation to form pellets, and the pellets were stored in a constant temperature bath at 80°C for 30 minutes, and then allowed to cool naturally to room temperature. These were used as toner samples, and the flow tester softening temperature (Ts) and flow start temperature (Tfb) were measured. The flow tester softening temperature (Ts) and flow starting temperature (Tfb) of [Toner 1] were determined from a flow curve measured using an elevated flow tester CFT500 model (manufactured by Shimadzu Corporation). The measurement conditions are as follows. Sample amount: 1.00±0.05g Starting temperature: 40℃ Achieved temperature: 200℃ Heating rate: 3.0℃ / min Test load: 22.5kgf Die hole diameter: 0.5 mm Die length: 1.0mm

[0134] In addition, when a shoulder corresponding to Ts does not appear on the piston stroke curve in measurements using the above flow tester, Ts is not automatically detected in the software attached to the flow tester, and in this case, Ts is assumed to be less than 40°C. The softening temperatures Ts of [Toner 2] to [Toner 7] were determined in the same manner. The results are shown in Table 2.

[0135] <Measurement of the tangent glass transition temperature Tg2nd of toner> The melting point and glass transition temperature (Tg) of [Toner 1] were measured using a DSC system (differential scanning calorimeter) ("Q-200", manufactured by TA Instruments). First, approximately 5.0 mg of the target sample was placed in an aluminum sample container, which was then placed on a holder unit and set in an electric furnace. Next, under a nitrogen atmosphere, the sample was heated from -50°C to 150°C at a heating rate of 10°C / min (first heating). The sample was then cooled from 150°C to -50°C at a cooling rate of 10°C / min, and further heated to 150°C at a heating rate of 10°C / min (second heating). DSC curves were measured during both the first and second heating periods using a differential scanning calorimeter (TA Instruments, model Q-200). From the obtained DSC curves, the DSC curve at the second heating was selected using the analysis program in the Q-200 system, and the tangent glass transition temperature Tg2nd of the target sample at the second heating was determined. The tangent glass transition temperatures Tg2nd of [Toner 2] to [Toner 7] were also determined in the same manner. The results are shown in Table 2.

[0136] <Measurement of Volume Average Particle Size of Toner> The volume average particle size of [Toner 1] was measured using a particle size measuring device (Multisizer III, manufactured by Beckman Coulter) with an aperture diameter of 100 μm, and the results were analyzed using analysis software (Beckman Coulter Multisizer 3 Version 3.51). Specifically, 0.5 ml of 10% by weight surfactant (alkylbenzene sulfonate, Neogen SC-A, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) was added to a 100 ml glass beaker, 0.5 g of each toner was added, and the mixture was stirred with a microspatula. 80 ml of ion-exchanged water was then added to obtain a dispersion. The resulting dispersion was dispersed for 10 minutes using an ultrasonic disperser (W-113MK-II, manufactured by Honda Electronics Co., Ltd.) to obtain a sample dispersion of [Toner 1]. The particle size of this sample dispersion of [Toner 1] was measured using the Multisizer III and an Isoton III (manufactured by Beckman Coulter) as the measurement solution. The measurement was performed by adding the sample dispersion of [Toner 1] dropwise so that the concentration indicated by the instrument was 8±2%, ensuring no particle size error and measurement reproducibility. The volume average particle size of [Toner 1] was calculated from the resulting particle size measurements. The volume average particle size of each of [Toner 2] to [Toner 7] was determined in the same manner. The volume average particle size of [Toner 1] to [Toner 7] was in the range of 18.0±0.5 μm.

[0137] (Manufacturing of two-component developers) [Creating the carrier] Silicone resin (organo straight silicone) 100 parts 100 parts toluene γ-(2-aminoethyl)aminopropyltrimethoxysilane 5 parts Carbon black 10 parts The above mixture was dispersed in a homomixer for 20 minutes to prepare a coating layer forming liquid. This coating layer forming liquid was applied to the core material using Mn ferrite particles with a weight average particle size of 35 μm, and dried using a fluidized bed coating device, controlling the temperature in the fluidized bed to 70°C so that the average film thickness on the core material surface would be 0.20 μm. The obtained carrier was fired in an electric furnace at 180° C. for 2 hours to obtain carrier A.

[0138] [Preparation of two-component developer] Each of the prepared toners and carrier A were uniformly mixed and charged for 5 minutes using a Turbula mixer (manufactured by Willy & Bachofen (WAB)) at 48 rpm to prepare two-component developers. The toner and carrier mixing ratio was adjusted to match the toner concentration of the initial developer for the evaluation machine: 7% by mass. Using the obtained two-component developer, toner images were thermally transferred onto fabric as follows, and each image was evaluated under the following evaluation methods and conditions.

[0139] (Creating evaluation images) [Example 1] (1) Two-component developer using [Toner 1] was set in all five stations of a RICOH Pro C7200S (manufactured by Ricoh Co., Ltd.), and the toner adhesion amount in each unit was 26.0 mg / cm 2 The development and transfer conditions were adjusted using a process controller so that the adhesion amount of [Toner 1] on release paper (product name: Force-in Paper, manufactured by Quick Art Co., Ltd.) was 130.0 mg / cm using all five stations. 2 A solid image was output. (2) A 100% polyester micro ripstop event jacket (manufactured by United Athle Co., Ltd.) was placed over the toner image on the release paper, and the toner image was ironed at 140°C with a load of 600 g / cm. 2 The toner image was thermally transferred onto the jacket by applying a heat of 1000 W for 10 seconds to prepare an image for evaluation.

[0140] [Examples 2 to 4] A two-component developer was prepared in the same manner as in Example 1, except that [Toner 1] in Example 1 was changed to [Toner 2] to [Toner 4]. An unfixed solid image was output, the toner image was fixed to a release paper, and the toner image on the release paper was thermally transferred to a cloth fabric to prepare an evaluation image.

[0141] [Comparative Examples 1 to 3] A two-component developer was prepared in the same manner as in Example 1, except that [Toner 1] in Example 1 was changed to [Toner 5] to [Toner 7]. An unfixed solid image was output, the toner image was fixed to a release paper, and the toner image on the release paper was thermally transferred to a cloth fabric to prepare an evaluation image.

[0142] <Image robustness evaluation method> The fixed images of Examples 1 to 4 and Comparative Examples 1 to 3 were subjected to a washing fastness test according to the test method of JIS0844:2011, and the image fastness was evaluated according to the following criteria. Of the results of the evaluation below, A to C were judged to be feasible as the toner of the present invention. The results are shown in Table 2. [Evaluation criteria] A: JIS0844 discoloration grayscale rank 5, and no image degradation even after 10 washes B: JIS0844 discoloration grayscale rank 5, and after 10 washes, some cracks appear in the image. C: JIS0844 discoloration grayscale rank 4-3 D: JIS0844 discoloration grayscale rank 2-1

[0143] <Method for evaluating fixation to flexible media> An adhesive tape having a predetermined adhesive strength was applied to the surface of the toner image thermally transferred onto the fabric of Examples 1 to 4 and Comparative Examples 1 to 3, and then the adhesive tape was peeled off to evaluate the remaining state of the toner image. Of the results of the evaluation below, A to C were judged to be feasible as the toner of the present invention. The results are shown in Table 2. [Evaluation criteria] A: Visually, there is no toner remaining on the tape, and the image density remains the same where the tape was removed. B: Visually, there is almost no toner remaining on the tape, and the image density remains almost unchanged where the tape is removed. C: Visually, a small amount of toner remains on the tape, but the image density at the location where the tape was peeled off remains almost unchanged. D: Visually, toner remains clearly on the tape, and the image where the tape was removed is faded.

[0144] <Image quality> As for image quality, the occurrence of abnormal images such as white streaks, black streaks, and fading of images was visually observed in the all-solid images and blank images printed after continuous printing, and evaluated according to the following evaluation criteria. The images on the fabrics of Examples 1 to 4 and Comparative Examples 1 to 3 were visually inspected for the presence or absence of pinholes, and evaluated according to the following evaluation criteria. Of the results of the evaluation below, A to C were judged to be feasible as the toner of the present invention. The results are shown in Table 2. [Evaluation criteria] A: No pinholes are visible to the naked eye B: One pinhole is visually detected C: Visually, 2-3 pinholes are found D: Visually inspected, 3 or more pinholes have occurred

[0145] [Table 1]

[0146] [Table 2]

[0147] The aspects of the present invention are as follows, for example. (1) A binder resin containing a polyester resin and a polyurethane elastomer, a release agent, and a benzoin-based compound, The softening temperature Ts is less than 20°C, The tangent glass transition temperature Tg2nd is less than 0°C. Electrophotographic toner characterized by: (2) The electrophotographic toner according to (1) above, wherein the benzoin-based compound is benzoin. (3) The toner for electrophotography according to (1) or (2) above, wherein the volume average particle size of the toner is 10 μm or more and 20 μm or less. (4) A toner storage unit containing the toner according to any one of (1) to (3) above. (5) A toner set comprising a color toner containing a binder resin and a colorant, and the toner according to any one of (1) to (3) above. (6) an electrostatic latent image carrier; and a developing means for developing an electrostatic latent image formed on the electrostatic latent image carrier using the toner according to any one of (1) to (3) above to form a toner image, It is detachable from the main body of the image forming apparatus. A process cartridge characterized by: (7) an electrostatic latent image carrier; an electrostatic latent image forming unit that forms an electrostatic latent image on the electrostatic latent image carrier; a developing unit that develops the electrostatic latent image using the toner according to any one of (1) to (3) above to form a toner image; a transfer means for transferring the toner image onto a recording medium; a fixing means for fixing the transferred image on the recording medium; An image forming apparatus comprising: (8) The transfer means is a primary transfer section that transfers the toner image to an intermediate transfer body; a secondary transfer section that transfers the toner image on the intermediate transfer body onto a recording medium; The image forming apparatus according to (7) above, (9) 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 formed on the electrostatic latent image carrier using the toner according to any one of (1) to (3) above to form a toner image; a transfer step of transferring the toner image formed on the electrostatic latent image carrier onto a recording medium; a fixing step of fixing the toner image transferred onto the recording medium; An image forming method comprising the steps of: (10) The transfer step a primary transfer step of transferring the toner image to an intermediate transfer member; a secondary transfer step of transferring the toner image on the intermediate transfer body onto a recording medium; The image forming method according to (9) above, (11) The image forming method according to (9) or (10) above, wherein the recording medium is a peelable support or a flexible recording medium having a surface roughness of 1 μm or more. (12) The image forming method according to any one of (9) to (11) above, wherein a toner image formed by the toner according to any one of (1) to (3) above is formed on the side closest to the peelable support or the flexible recording medium. (13) The image forming method according to (11) or (12) above, wherein the flexible recording medium is a fabric made of fibers. (14) A transfer sheet having a release surface on at least one side; a color toner layer adhered to the outermost surface of the release surface side of the transfer sheet, and a toner layer formed by the toner according to any one of (1) to (3) above adhered to the side of the transfer sheet closest to the release surface side; A transfer sheet comprising: (15) The transfer sheet according to (14) above, wherein the transfer sheet is a peelable support or a flexible recording medium having a surface roughness of 1 μm or more. [Explanation of symbols]

[0148] 1 Paper feed section 2 Paper feed roller 3, 4 Registration rollers 5, 11, 17, 23, 29 Photoreceptor 6, 12, 18, 24, 30 Charger 7, 13, 19, 25, 31 Exposure light 8, 14, 20, 26, 32 Developing means 9, 15, 21, 27, 33 Cleaning device 10, 16, 22, 28, 34 Primary transfer device 35 Yellow toner developing unit 36 Magenta toner developing unit 37 Cyan toner development unit 38 Black toner developing unit 39 Toner developing unit of the present invention 30 Charger 40 Intermediate transfer belt 41 Secondary transfer device 43 Fixing device 47 Belt cleaning device 50 Toner developing unit 51 Photoreceptor 52 Developing device 53 Cleaning device 54 Charging device [Prior art documents] [Patent documents]

[0149] [Patent Document 1] Patent No. 5510517 [Patent Document 2] Japanese Patent Application Laid-Open No. 2012-008172 [Patent Document 3] Patent Application No. 2022-183615

Claims

1. The binder resin includes a polyester resin and a polyurethane elastomer, a release agent, and a benzoin-based compound, The softening temperature Ts is less than 20°C, The tangent glass transition temperature Tg2nd is less than 0°C. Electrophotographic toner characterized by:

2. 2. The electrophotographic toner according to claim 1, wherein the benzoin-based compound is benzoin.

3. 2. The toner for electrophotography according to claim 1, wherein the volume average particle size of the toner is 10 [mu]m or more and 20 [mu]m or less.

4. A toner storage unit containing the toner according to any one of claims 1 to 3.

5. A toner set comprising a color toner containing a binder resin and a colorant, and the toner according to claim 1 .

6. an electrostatic latent image carrier; and a developing means for developing an electrostatic latent image formed on the electrostatic latent image carrier using the toner according to any one of claims 1 to 3 to form a toner image, It is detachable from the main body of the image forming apparatus. A process cartridge characterized by:

7. an electrostatic latent image carrier; an electrostatic latent image forming unit that forms an electrostatic latent image on the electrostatic latent image carrier; a developing unit that develops the electrostatic latent image with the toner according to any one of claims 1 to 3 to form a toner image; a transfer means for transferring the toner image onto a recording medium; a fixing means for fixing the transferred image on the recording medium; An image forming apparatus comprising:

8. The transfer means is a primary transfer section that transfers the toner image to an intermediate transfer body; a secondary transfer section that transfers the toner image on the intermediate transfer body onto a recording medium; The image forming apparatus according to claim 7 , comprising:

9. 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 formed on the electrostatic latent image carrier with the toner according to claim 1 to form a toner image; a transfer step of transferring the toner image formed on the electrostatic latent image carrier onto a recording medium; a fixing step of fixing the toner image transferred onto the recording medium; An image forming method comprising the steps of:

10. The transferring step a primary transfer step of transferring the toner image to an intermediate transfer member; a secondary transfer step of transferring the toner image on the intermediate transfer body onto a recording medium; The image forming method according to claim 9 , comprising:

11. 10. The image forming method according to claim 9, wherein the recording medium is a peelable support or a flexible recording medium having a surface roughness of 1 [mu]m or more.

12. 10. The image forming method according to claim 9, wherein the toner image formed by the toner according to claim 1 is formed on a side closest to the peelable support or the flexible recording medium.

13. 12. The image forming method according to claim 11, wherein the flexible recording medium is a fabric made of fibers.

14. a transfer sheet having a release surface on at least one side; a color toner layer adhered to the outermost surface of the release surface side of the transfer sheet, and a toner layer formed by the toner according to any one of claims 1 to 3 adhered to the side of the transfer sheet closest to the release surface side; A transfer sheet comprising:

15. The transfer sheet according to claim 14, wherein the transfer sheet is a release support or a flexible recording medium having a surface roughness of 1 μm or more.

Images