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

Abstract

To provide a toner that adheres well to flexible media such as cloth, which cannot be fixed with conventional toners, and that also possesses sufficient flexibility. [Solution] The toner according to one embodiment of the present invention is a toner containing a binder resin, and has a true density of 1.30 g / cm³. 3 More than 1.80g / cm 3 The following conditions apply: the average circularity is less than 0.93, the volume average particle size is 10 μm or more and 30 μm or less, the loose apparent bulk density is less than 0.55, and the binder resin contains a polyurethane resin, with the polyurethane resin content being 51% by mass or more relative to the toner.

Description

[Technical Field]

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

[0002] Electrophotography, which forms a visible image by developing an electrostatic latent image with a developer, involves forming an electrostatic latent image on an electrostatic latent image carrier containing a photoconductive material, developing the electrostatic latent image with a developer containing toner to form a toner image, transferring the toner image to a transfer material such as paper, and then fixing it by heating and pressurizing to form a fixed image.

[0003] To form full-color images using electrophotography, it is common to use a toner set that combines three process color toners—cyan, magenta, and yellow—with a black toner.

[0004] In recent years, with the widespread adoption of electrophotographic color image forming machines, the applications of printed materials have also diversified. Particularly in the field of custom-designed consumer goods, there is a growing need for electrophotographic printing on materials that cannot be printed on (fixed) with conventional electrophotographic toners intended for paper. Specifically, there is increasing demand for printing on fabric materials 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 that allows an image to be heat-melted and adhered to a print target object on a white background without using an adhesive, and does not damage the pulverizer.

[0006] Patent Document 2 discloses an image forming method that suppresses overheating in the nip area, prevents problems such as hot offset, allows for the formation of a good image, improves crease fixing and blocking resistance, and further reduces power consumption in the fixing process through low-temperature fixing. [Overview of the Initiative] [Problems that the invention aims to solve]

[0007] Toners used to form fixed images on fabric media require characteristics not found in conventional paper media toners, such as sufficient fixation to uneven fabric fibers, and a fixed toner layer with appropriate flexibility that allows the toner layer to follow the deformation of the fabric. However, a toner that is both highly fixable to media made of flexible fibers like fabric and highly flexible has yet to be found.

[0008] One embodiment of the present invention aims to provide a toner that adheres well to a flexible fiber medium such as cloth, which is difficult to adhere to with conventional toners, and that also possesses sufficient flexibility. [Means for solving the problem]

[0009] A toner according to one embodiment of the present invention is a toner containing a binder resin, and has a true density of 1.30 g / cm³. 3 More than 1.80g / cm 3 The following conditions apply: the average circularity is less than 0.93, the volume average particle size is 10 μm or more and 30 μm or less, the loose apparent bulk density is less than 0.55, and the binder resin contains a polyurethane resin, with the polyurethane resin content being 51% by mass or more relative to the toner. [Effects of the Invention]

[0010] According to one embodiment of the present invention, it is possible to provide a toner that can be sufficiently fixed to a medium made of flexible fibers such as cloth, which cannot be fixed with conventional toners, and that also has sufficient flexibility. [Brief explanation of the drawing]

[0011] [Figure 1] This is a schematic diagram showing an example of an image forming apparatus according to one embodiment of the present invention. [Figure 2]This is a schematic diagram showing the main components of an example of an image forming apparatus according to one embodiment of the present invention. [Figure 3] This is a schematic diagram showing the main components of an example of an image forming apparatus according to one embodiment of the present invention. [Figure 4] This is an average cross-sectional SEM image of the crushed toner component molten and kneaded product of the toner from Example 1. [Modes for carrying out the invention]

[0012] Generally, cloth is flexible and often consists of fibers. When printing an image on such a flexible fibrous medium using toner, certain characteristics not found in conventional paper-based toners are required, such as sufficient adhesion to the uneven surface of the cloth fibers, and the ability of the fixed toner layer to have appropriate flexibility so that its deformation can follow the unevenness or deformation of the cloth.

[0013] Therefore, after diligent research, the inventors discovered that using a toner containing 51% by mass or more of polyurethane resin significantly improves the toner's fixation to the fabric medium and imparts appropriate flexibility to the fixed toner layer.

[0014] On the other hand, the true density is 1.3 g / cm³. 3 With the relatively high density and relatively large particle size (volume average particle size of 9 μm or more) toners described above, the toner tends to compact, resulting in poor transportability by screw. Furthermore, because the toner particles tend to fuse together, there is a tendency for the toner to adhere to and solidify on the screw during toner transport (screw lock). The inventors also investigated this screw lock problem. As a result, they found that by setting the true density, average circularity, volume average particle size, and loose apparent bulk density of the toner within specific ranges, screw lock can be suppressed, and a toner that adheres sufficiently to a flexible fiber medium such as cloth and has sufficient flexibility can be obtained.

[0015] In other words, one embodiment of the present invention is a toner containing a binder resin, wherein the true density is 1.30 g / cm³.3 1.80 g / cm or more 3 less than, the average circularity is less than 0.93, the volume average particle diameter is 10 μm or more and 30 μm or less, the loose apparent bulk density is less than 0.55, the binder resin contains a polyurethane resin, and the content of the polyurethane resin is 51% by mass or more with respect to the toner, to provide a toner.

[0016] Hereinafter, embodiments of the present invention will be described in detail. Note that the embodiments are not limited by the following description, and can be appropriately changed without departing from the gist of the present invention. In the present specification, "~" indicating a numerical range means including the numerical values described before and after it as the lower limit value and the upper limit value, unless otherwise specified.

[0017] <Toner> The toner of the present embodiment is a toner containing a binder resin, having a true density of 1.30 g / cm 3 or more and 1.80 g / cm 3 less than, the average circularity is less than 0.93, the volume average particle diameter is 10 μm or more and 30 μm or less, the loose apparent bulk density is less than 0.55, the binder resin contains a polyurethane resin, and the content of the polyurethane resin is 51% by mass or more with respect to the toner. Thereby, the toner of the present embodiment can be sufficiently fixed to a medium made of flexible fibers such as cloth and exhibit sufficient flexibility. Further, the toner of the present embodiment can suppress the occurrence of screw lock.

[0018] The true density of the toner is 1.30 g / cm 3 or more and 1.80 g / cm 3 less than. When the true density of the toner is less than 1.30 g / cm 3 constraints occur in incorporating a large amount of a true density or high specific gravity material (such as a white titanium oxide pigment) to hide the fabric color. On the other hand, when the true density of the toner is greater than 1.80 g / cm 3 there are problems such as the toner being likely to compact and the toner conveyance property being poor, so that the toner adheres to the conveyance screw or the like.

[0019] (Method for measuring true density) True density refers to a density where only the volume occupied by the substance itself is used for density calculation. The true density of toner can be measured using the Accupic II 1340 unit (manufactured by Shimadzu Corporation).

[0020] The average circularity of the toner is less than 0.93. If the average circularity of the toner is 0.93 or higher, the toner powder tends to compact under its own weight. Also, because it loosens and the apparent bulk density becomes relatively high, in this embodiment of toner with a relatively large particle size of 10 μm to 30 μm, toner transportability is poor, and problems such as toner adhering to transport screws occur. The average circularity of the toner is preferably less than 0.90. Furthermore, from the viewpoint of ensuring fluidity and transferability, the lower limit of the average circularity is preferably 0.80.

[0021] (Method for measuring average circularity) The average circularity of toner is defined as (perimeter of a circle with the same area as the particle projection area / perimeter of the particle projection image) × 100%. The average circularity of toner can be measured using a flow-type particle image analyzer (FPIA®-3000, manufactured by Sysmex Corporation). An example is shown below.

[0022] 0.1 ml to 0.5 ml of 10% by mass surfactant (alkylbenzenesulfonate, Neogen® SC-A, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) is added to a 100 ml glass beaker, and 0.1 g to 0.5 g of toner is added and stirred with a micro spatula. 80 ml of deionized water is then added to obtain a dispersion. The obtained dispersion is subjected to dispersion treatment using an ultrasonic disperser (manufactured by Honda Electronics Co., Ltd.) for 3 minutes to obtain a sample for measurement. For the sample for measurement, the average circularity of the toner is measured using analysis software (FPIA®-3000) until the toner particle concentration reaches 5,000 particles / μL to 15,000 particles / μL.

[0023] In this measurement method, it is important to set the toner particle concentration of the measurement sample to 5,000 particles / μL to 15,000 particles / μL for reproducibility in measuring average circularity. The amount of surfactant required varies depending on the hydrophobicity of the toner, as with the measurement of toner particle size described above. Adding more than the required amount will generate noise due to bubbles, while adding less than the required amount will result in insufficient dispersion because the toner cannot be sufficiently wetted. Furthermore, the amount of toner to add varies depending on the particle size; less is needed for small particles, and more is needed for large particles. When the volume average particle size of the toner is 3 μm to 10 μm, it is possible to adjust the toner concentration of the measurement sample to 5,000 particles / μL to 15,000 particles / μL by adding 0.1 g to 0.5 g of toner.

[0024] The volume-average particle size of the toner is between 10 μm and 30 μm. A volume-average particle size of 10 μm to 30 μm allows for a higher pile height in the toner layer, making it easier to fill in irregularities on the surface of flexible media such as cloth, thus providing excellent opacity and suitability. Furthermore, considering the trade-off with transferability, a volume-average particle size of 30 μm or less is preferable.

[0025] (Method for measuring volume-average particle size) The volume-average particle size, or particle size based on volume percentage, can be measured, for example, using a laser diffraction particle size distribution analyzer ("SALD-2300," manufactured by Shimadzu Corporation). An example is shown below.

[0026] 0.5 ml of 10% by mass surfactant (alkylbenzenesulfonate, Neogen® SC-A, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) is added to a 100 ml glass beaker, 2 g to 4 g of toner is added and stirred with a micro spatula, and 80 ml of deionized water is added to obtain a dispersion. The obtained dispersion is dispersed in an ultrasonic disperser (W-113MK-II, manufactured by Honda Denshi Co., Ltd.) for 10 minutes to obtain a sample for measurement. The volume-average particle size of the sample is measured using a laser diffraction particle size distribution analyzer.

[0027] The apparent bulk density of the toner is less than 0.55. A lower apparent bulk density of the toner means that the toner powder is less likely to compact, but if the apparent bulk density of the toner exceeds 0.55, the toner is more likely to compact, resulting in poor toner transportability and problems such as toner sticking to the transport screw. The apparent bulk density of the toner is preferably less than 0.50. Furthermore, the lower limit of the apparent bulk density of the toner is preferably 0.35 or higher from the viewpoint of transferability and fluidity. Specifically, it is preferable that the average circularity of the toner is less than 0.90 and the apparent bulk density of the toner is less than 0.50. As a result, the toner of this embodiment can further suppress the occurrence of screw lock.

[0028] (Method for measuring loose apparent bulk density) A graduated cylinder with a stopper, whose weight was measured in advance: 50 cm 3 Add 14g of toner to (±0.25ml (TC20℃)). Next, stopper the graduated cylinder and shake it 10 times by hand to agitate the toner. Then, let it stand for 10 minutes and determine the toner volume. The value calculated based on the following formula (1) is taken as the loose apparent bulk density. {(Weight of toner + graduated cylinder with stopper) - (Weight of graduated cylinder with stopper)} / (Volume of toner) ... (1)

[0029] The toner softening temperature is preferably below 40°C. This allows the toner in this embodiment to exhibit greater flexibility, but it has the side effect of making screw locking more likely to occur.

[0030] (Method for measuring softening temperature Ts) For measuring the softening temperature, a flow tester (Shimadzu Corporation, CFT-500D) was used. Toner was pressure-molded into tablets at the lowest possible pressure to form pellets. These pellets were stored in an 80°C constant temperature bath for 30 minutes, and then allowed to cool naturally to room temperature. The toner samples were used, and the flow tester softening temperature (Ts) was measured. The toner's flow tester softening temperature (Ts) was determined from the flow curve measured using an elevated flow tester, model CFT500 (Shimadzu Corporation). The measurement conditions are as follows: Sample quantity: 1.00 ± 0.05 g Starting temperature 40℃ Achieved temperature 200℃ Heating rate: 3.0℃ / min Test load: 35 kgf Die hole diameter 0.5mm Die length 1.0mm

[0031] [Binding resin] The toner of this embodiment contains a binder resin (fixing resin) containing polyurethane resin. Polyurethane resin generally has excellent tensile strength, abrasion resistance, elasticity, and oil resistance.

[0032] The polyurethane resin content is 51% by mass or more relative to the toner (total mass of toner). More preferably, the polyurethane resin content is in the range of 51% by mass or more and 90% by mass or less relative to the toner. If the polyurethane resin content is 51% by mass or more relative to the toner, sufficient fixation of the toner to a flexible medium such as cloth and flexibility of the toner layer after fixation can be obtained. If it is 90% by mass or less, the thermal storage properties of the toner will not deteriorate and there will be no risk of aggregation of toner particles.

[0033] (Confirmation and quantification of the presence of resin in the toner) The molecular weight and melting point of the resin may be measured individually, but they can also be separated from the actual toner using gel permeation chromatography (GPC), and the molecular weight, melting point, and mass ratio of the constituent components can be calculated by applying the analytical methods described later to each separated component.

[0034] The separation of each component by GPC can be performed, for example, by the following method. In GPC measurements using THF (tetrahydrofuran) as the mobile phase, the eluate is separated using a fraction collector or similar device, and the fraction corresponding to the desired molecular weight portion of the total integral of the elution curve is collected.

[0035] After concentrating and drying this collected eluate using an evaporator or the like, the solid components are dissolved in a deuterated solvent such as deuterated chloroform or deuterated THF. 1 1H-NMR measurements are performed, and the ratio of constituent monomers in the resin in the eluted components is calculated from the integral ratio of each element.

[0036] Another method involves concentrating the eluate, performing hydrolysis with sodium hydroxide, and then qualitatively and quantitatively analyzing the decomposition products using high-performance liquid chromatography (HPLC) to calculate the constituent monomer ratios.

[0037] <<Method for separating toner components>> An example of a means for separating each component when analyzing the aforementioned toner is shown in detail. First, 1 g of toner is added to 100 mL of THF, and under conditions of 25°C, a solution is obtained by stirring for 30 minutes until the soluble components are dissolved. This is filtered through a membrane filter with a mesh size of 0.2 μm to obtain the THF-soluble components in the toner. Next, this is dissolved in THF to prepare a sample for GPC measurement, and then injected into the GPC used for molecular weight measurement of each resin as described above. On the other hand, a fraction collector is placed at the eluate outlet of the GPC to separate the eluate at predetermined count intervals, and the eluate is obtained at intervals of 5% area percentage from the start of elution (the rising point of the curve) on the elution curve. Next, for each eluate, 30 mg of the sample is dissolved in 1 mL of deuterated chloroform, and 0.05 vol% tetramethylsilane (TMS) is added as a reference substance. The solution is packed into a 5 mm diameter NMR measuring glass tube, and a nuclear magnetic resonance spectrometer (JEOL Ltd. JNM-AL400) is used to perform 128 integrations at a temperature of 23°C to 25°C to obtain the spectrum. The monomer composition and proportions of polyester resin and urethane resin contained in the toner can be determined from the peak integration ratio of the obtained spectrum.

[0038] For example, peak assignment is performed as follows, and the component ratios of the constituent monomers are determined from the integral ratios of each peak. The attribution of the peak is, for example, Around 8.25 ppm: Derived from the benzene ring of trimellitic acid (one hydrogen atom) Around 8.07 ppm to 8.10 ppm: Derived from the benzene ring of terephthalic acid (4 hydrogen atoms). Around 7.1 ppm to 7.25 ppm: Derived from the benzene ring of bisphenol A (4 hydrogen atoms) Around 6.8 ppm: Derived from the benzene ring of bisphenol A (4 hydrogen atoms) and the double bond of fumaric acid (2 hydrogen atoms). Approximately 5.2 ppm to 5.4 ppm: Derived from tin in the bisphenol A propylene oxide adduct (equivalent to one hydrogen atom) Around 3.7 ppm to 4.7 ppm: Derived from methylene in the bisphenol A propylene oxide adduct (2 hydrogen atoms) and from methylene in the bisphenol A ethylene oxide adduct (4 hydrogen atoms). Around 1.6 ppm: Derived from the methyl group of bisphenol A (equivalent to 6 hydrogen atoms) It can be done this way.

[0039] <<Analysis of THF-insoluble components in toner>> The extraction of THF-insoluble components from the aforementioned toner can be carried out, for example, as follows. One part toner is added to 40 parts THF and refluxed for 6 hours. Then, the insoluble components are settled using a centrifuge to separate the insoluble components from the supernatant. The insoluble components are dried at 40°C for 20 hours to obtain the THF insoluble components. The composition of THF-insoluble components can be analyzed by NMR measurements in solution or solid form, as well as by X-ray diffraction, GC / MSLC / MS, IR measurements, and other methods. For a simpler method, analysis can be performed using a GC-MS method involving simultaneous thermal decomposition and methylation with a methylation reagent, for example, as shown below. Equipment name: Shimadzu Corporation QP2010 Frontier Lab Py2020D Data analysis software: Shimadzu GCMSsolution; Heating temperature: 280℃; Reaction pyrolysis temperature: 300℃; Column name: Ultra ALLOY-5; L=30m; ID=0.25mm; Film=0.25μm Constant temperature bath temperature: 50℃ (held for 1 minute) ~ 10℃ / min ~ 330℃ (held for 11 minutes) Carrier gas: constant 53.6 kPa, He 1.0 mL / min Infusion mode: Split (1:100) Ionization method: EI method (70 eV) Measurement mode: Scan mode Library: NIST 20 MASS SPECTRAL

[0040] The polyurethane resin preferably has structural units derived from at least an aliphatic diol, and the glass transition temperature of the polyurethane resin is preferably 0°C or lower. As a result, the toner of this embodiment can be sufficiently fixed to a flexible fiber medium such as cloth, and can exhibit greater flexibility.

[0041] Specifically, the polyurethane resin preferably contains at least 1,4-butanediol, adipic acid, and diphenylmethane diisocyanate, and the weight-average molecular weight of the polyurethane resin is preferably between 40,000 and 130,000. This allows the toner of this embodiment to be sufficiently fixed to a flexible fiber medium such as cloth, and to exhibit greater flexibility.

[0042] The weight-average molecular weight of the polyurethane resin is preferably 40,000 to 130,000, more preferably 40,000 to 110,000, and even more preferably 40,000 to 100,000. If the weight-average molecular weight is 40,000 or more, there is no risk of the fixed image melting when ironed, and if the weight-average molecular weight is 130,000 or less, it is easier to melt and knead the adhesive with other toner components during tonerization.

[0043] (Measurement of weight-average molecular weight) The weight-average molecular weight of the resin used in toner can be obtained by measuring the molecular weight distribution of the THF (tetrahydrofuran) dissolved in the resin using a gel permeation chromatography (GPC) analyzer. There are no particular restrictions on the GPC analyzer, and one can be appropriately selected depending on the purpose. For example, the GPC-150C (manufactured by Waters) can be used under its trade name.

[0044] There are no particular restrictions on the column used for measuring weight-average molecular weight, and it can be appropriately selected according to the purpose. Examples include the following product names: KF801 (organic solvent-based SEC (GPC) column), KF802 (organic solvent-based SEC (GPC) column), KF803 (organic solvent-based SEC (GPC) column), KF804 (organic solvent-based SEC (GPC) column), KF805 (organic solvent-based SEC (GPC) column), KF806 (organic solvent-based SEC (GPC) column), and KF807 (organic solvent-based SEC (GPC) column) (all manufactured by Showa Denko K.K.).

[0045] There are no particular restrictions on the method for measuring the weight-average molecular weight of the resin used in toner; it can be appropriately selected depending on the purpose. For example, it can be done by the following method.

[0046] The column is stabilized in a heat chamber at 40°C, and THF is flowed through it as the solvent at a flow rate of 1 mL / min. Next, 0.05 g of the sample is thoroughly dissolved in 5 g of THF, and then filtered through a pretreatment filter (e.g., product name: Chromatodisk, pore size: 0.45 μm, manufactured by Kurabo Industries Ltd.) to adjust the sample concentration to 0.05% to 0.6% by mass. 50 μL to 200 μL of the adjusted THF sample solution is injected into the column to separate the THF dissolved in the THF sample solution. Subsequently, the weight-average molecular weight (Mw) of the THF dissolved in the THF sample solution can be measured by converting it to molecular weight using a detector (e.g., a differential refractive index (RI) detector (device name: GPC-150C, manufactured by Waters)).

[0047] The weight-average molecular weight Mw and number-average molecular weight Mn of the THF dissolved in the sample are measured by calculating the relationship between the logarithm of a calibration curve created using several monodisperse polystyrene standard samples and the count, which represents the molecular weight distribution of the sample.

[0048] For calibration curve preparation, it is preferable to use standard polystyrene samples from Pressure Chemical Co., Ltd. or Toyo Soda Industries Co., Ltd., with molecular weights of 6×10², 2.1×10², 4×10², 1.75×10⁴, 5.1×10⁴, 1.1×10⁵, 3.9×10⁵, 8.6×10⁵, 2×10⁶, and 4.48×10⁶, and to use at least 10 standard polystyrene samples. It is also preferable to use an RI (refractive index) detector.

[0049] There are no particular restrictions on the specific product names of the polyurethane resins used; they can be appropriately selected according to the purpose. Examples include Hot Melt Powder ECOFREEN POWDER (manufactured by ECOFREEN), T8175N (manufactured by DIC Covestropolymer), and P22MBRNAT (manufactured by Nippon Miractran).

[0050] The binder resin may contain polyurethane resin and other resins. Conventional known resins can be used as the other resins. Examples include styrene-based resins (monopolymers or copolymers containing styrene or styrene-substituted compounds) such as styrene, poly-α-stylstyrene, styrene-chlorostyrene copolymer, styrene-propylene copolymer, styrene-butadiene copolymer, styrene-vinyl chloride copolymer, styrene-vinyl acetate copolymer, styrene-maleic acid copolymer, styrene-acrylic acid ester copolymer, styrene-methacrylate ester copolymer, styrene-α-methyl chloroacrylate copolymer, and styrene-acrylonitrile-acrylic acid ester copolymer; epoxy resins; vinyl chloride resins; rosin-modified maleic acid resins; phenolic resins; polyethylene resins; polypropylene resins; petroleum resins; polyester resins; ketone resins; ethylene-ethyl acrylate copolymers; xylene resins; and polyvinyl butyrate resins. Furthermore, the manufacturing methods for these resins are not particularly limited, and methods such as bulk polymerization, solution polymerization, emulsion polymerization, and suspension polymerization can be used.

[0051] The binder resin preferably contains polyurethane resin and polyester resin. Polyester resin is generally suitable for the toner in this embodiment because it can be fixed at low temperatures while maintaining heat resistance compared to other resins.

[0052] Polyester resins are preferably obtained by condensation polymerization of an alcohol and a carboxylic acid. There are no particular restrictions on the alcohol used, and it can be appropriately selected depending on the purpose. Examples include glycols such as ethylene glycol, diene glycol, triethylene glycol, and propylene glycol; etherified bisphenols such as 1,4-bis(hydroxymetha)cyclohexane and bisphenol A; other dihydric alcohol monomers; and trihydric or higher polyhydric alcohol monomers.

[0053] Furthermore, there are no particular restrictions on the carboxylic acid, and it can be appropriately selected depending on the purpose. Examples 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-naphthalentricarboxylic acid, 1,2,5-hexanetricarboxylic acid, 1,3-dicarboxyl-2-methylenecarboxypropane, and 1,2,7,8-octanetetracarboxylic acid.

[0054] It is preferable that both the softening temperature Ts and the tangential glass transition temperature Tg2nd of the polyurethane resin are 45°C or lower. If both the softening temperature Ts and the tangential glass transition temperature Tg2nd of the polyurethane resin are 45°C or lower, the flexibility of the toner layer after fixing can be ensured.

[0055] Furthermore, it is preferable that both the softening temperature Ts and the tangential glass transition temperature Tg2nd of the polyester resin are 60°C or higher. If both the softening temperature Ts and the tangential glass transition temperature Tg2nd of the polyester resin are 60°C or higher, the heat resistance of the toner image can be ensured.

[0056] In the cross-section of the toner, it is preferable to see island-like domains, and in particular, it is preferable to see polyester resin domains in a sea of ​​polyurethane resin, thus creating a sea-island structure. The sea-island structure refers to a structure in which, if the continuous phase of one component contained in the toner is described as a "sea" (hereinafter sometimes referred to as a matrix), other components exist in the form of "islands" (hereinafter sometimes referred to as domains) within the "sea". Components present in the toner at 51% by mass or more form the sea, while components present at less than 49% by mass and incompatible with the sea components exist as island-like domains.

[0057] When polyester resin and polyurethane resin are used in combination, an immiscible sea-island structure can be formed, making it easier to form the sea-island structure. Therefore, it is preferable to use polyurethane resin in combination with polyester resin. If this sea-island structure is not observed in the toner cross-section and the polyurethane resin and polyester resin are in a miscible state, the properties of each resin will not be exhibited, and the toner image will be particularly prone to cracking after fixing.

[0058] In the case where the toner of this embodiment contains polyurethane resin and polyester resin, it is preferable that the domains of the sea-island structure in the toner cross-section contain polyester resin and the matrix contains polyurethane resin, and it is preferable that the domains and matrix of the toner cross-section are incompatible.

[0059] (Observation of incompatible domains) The size and shape of domains in the toner can be confirmed by observing backscattered electron images obtained using a scanning electron microscope (SEM). The difference in color between the island regions (domains) and the marine regions (matrix) in the sea-island structure of the toner confirms the presence of marine regions and island regions (incompatible domains). To enhance contrast and facilitate the distinction between island regions and marine regions, staining with ruthenium tetroxide may be performed as needed.

[0060] The following procedure and conditions are an example of how to observe backscattered electron images using a scanning electron microscope.

[0061] The sea-island structure of this embodiment can be observed similarly with both toner particles and crushed toner component molten mixtures. Toner particles or crushed toner component molten mixture particles are embedded in epoxy resin, a cross-section is prepared, and then observation can be performed using a scanning electron microscope (Hitachi, Ltd., SU8230) under the following conditions. In this case, the unstained areas are observed as dark areas, making them distinguishable from the stained areas (bright areas). • Acceleration voltage: 5kV • Emission current: 10μA • Probe current: Norm • Condenser lens 1:5.0 WD: 8.0mm • Observation mode: SE Magnification: ×2,000 or ×5,000

[0062] The toner of this embodiment contains a binder resin (fixing resin) and may optionally contain a release agent, a colorant, a charge control agent, an external additive, a developer, and other components (fluidity improver, cleaning performance improver, magnetic material).

[0063] [Release agent] In the toner of this embodiment, there are no particular restrictions on the type of release agent (wax type) that can be used, and it can be appropriately selected according to the purpose. One type may be used alone, or two or more types may be used in combination.

[0064] There are no particular restrictions on the release agent, and it can be appropriately selected depending on the purpose. Examples include liquid paraffin, microcrystalline wax, natural paraffin, synthetic paraffin, polyolefin wax, and partial oxides thereof, or aliphatic hydrocarbons such as fluoride and chloride, 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, zinc stearate, calcium stearate, magnesium stearate, aluminum stearate, zinc oleate, zinc palmitate, magnesium palmitate, zinc myristate, zinc laurate, zinc behenate, fatty acid esters, and polyvinylidene fluoride. Of these, it is preferable to contain at least ester waxes, including fatty acid esters.

[0065] When a maleic acid-modified polyolefin having polypropylene blocks in its main chain is included in the toner, a high content can cause a waste paper jam during fixing, as the toner and the fixing roller (or fixing belt) cannot be separated. This problem can be suppressed by adding ester wax as a release agent. Furthermore, the maleic acid-modified polyolefin having polypropylene blocks in its main chain can finely disperse the ester wax.

[0066] There are no particular restrictions on the amount of release agent contained in the toner, and it can be appropriately selected depending on the purpose, but it is preferably 0.1% to 8.0% by mass, and more preferably 1.0% to 6.0% by mass. If the content is 0.1% by mass or more, the toner and the fixing roller (or fixing belt) will separate during fixing, suppressing waste paper jams. If the content is 8.0% by mass or less, the toner can be sufficiently fixed to the plastic film.

[0067] [Coloring agent] There are no particular restrictions on the colorant used in the toner of this embodiment, and any commonly used colorant can be appropriately selected and used. Examples include black toner, cyan toner, magenta toner, yellow toner, white pigment, green toner, and blue toner.

[0068] There are no particular restrictions on the black toner, and it can be selected as appropriate depending on the purpose. However, carbon black alone or a mixture of carbon black as the main component with copper phthalocyanine or other materials to adjust the hue and brightness is preferred.

[0069] There are no particular restrictions on the cyan toner, and it can be selected appropriately depending on the purpose, but copper phthalocyanine in a 15:3 ratio with pigment blue, or a mixture of aluminum phthalocyanine and a coloring agent is preferred.

[0070] There are no particular restrictions on the magenta toner, and it can be selected as appropriate depending on the purpose, but pigment red 53:1, pigment red 81, pigment red 122, and pigment red 269 can be used individually or in mixtures.

[0071] There are no particular restrictions on the yellow toner used, and it can be selected as appropriate depending on the purpose. However, Pigment Yellow 74, Pigment Yellow 155, Pigment Yellow 180, and Pigment Yellow 185 can be used individually or in combination. Using Pigment Yellow 185 alone, or in combination with Pigment Yellow 74, is preferable in terms of saturation and preservation.

[0072] There are no particular restrictions on the white pigment; it can be appropriately selected according to the purpose, and titanium dioxide with surface treatments such as silicon, zirconia, aluminum, or polyol can be used.

[0073] There are no particular restrictions on the type of green toner used; 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.

[0074] There are no particular restrictions on the type of blue toner used; it can be selected appropriately depending on the purpose. Examples include pigment blue 15:1 and pigment violet 23.

[0075] Furthermore, when the toner of this embodiment is used as the base layer (the layer on the side closest to the release support or recording medium where the image is formed), by forming a conventional toner layer on top of it, the conventional toner can also be well fixed onto fabric media with many fibrous irregularities. Furthermore, since the toner of this embodiment has rubber elasticity, the printed image is less likely to crack when stretched, bent, or washed. From this viewpoint, and from the viewpoint of not impairing the color of the toner layered on top, when using the toner of this embodiment as a base layer, it is preferable that the colorant contained in the toner is white and / or colorless (contains no colorant). If the colorant contained in the toner is white, from the viewpoint of not impairing the color of the toner layered on top, it is preferable that the colorant be contained in an amount of 10% to 50% by mass when the total amount of toner is 100% by mass. If the content of white colorant is less than 10% by mass, the opacity of the base layer will be insufficient, and if the content of white colorant exceeds 50% by mass, the resin content in the toner will be insufficient, resulting in insufficient image strength.

[0076] [Static Control Agent] The toner of this embodiment may contain a charge control agent.

[0077] There are no particular limitations on the charge control agent, and it can be appropriately selected according to the purpose. Examples include modified products with nigrosine and 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; diorganostin oxides such as dibutyltin oxide, dioctyltin oxide, and dicyclohexyltin oxide; diorganostin borates such as dibutyltin borate, dioctyltin borate, and dicyclohexyltin borate; organometallic complexes, chelate compounds, monoazometallic complexes, acetylacetone metal complexes, aromatic hydroxycarboxylic acids, aromatic dicarboxylic acid-based metal complexes, 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 bisphenol. These can be used individually or in combination of two or more types.

[0078] When these charge control agents are added internally to toner for electrophotographic development, there are no particular restrictions on the content, and it can be set appropriately depending on the purpose, but it is preferable to add 0.1% to 10% by mass relative to the total amount of binder resin. Also, since the charge control agent may cause coloration, it is preferable to select one that is as transparent as possible, except for black toner.

[0079] [External Additives] The toner of this embodiment can use inorganic fine particles or the like as an external additive.

[0080] There are no particular restrictions on the inorganic fine particles used as external additives, and they can be appropriately selected according to the purpose. Examples 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, and silicon nitride. Among these, silica, alumina, and titanium oxide are preferred.

[0081] Furthermore, inorganic fine particles may be surface-treated with a hydrophobic treatment agent. There are no particular restrictions on the hydrophobic treatment agent, and it can be appropriately selected depending on the purpose. For example, silane coupling agents, silylation agents, silane coupling agents having alkyl fluoride, organic titanate coupling agents, and aluminum coupling agents are examples of preferred surface treatment agents. In addition, sufficient effects can be obtained by using silicone oil as a hydrophobic treatment agent.

[0082] Furthermore, there are no particular restrictions on the average diameter of the primary inorganic particles, and it can be appropriately selected depending on the purpose, but 5 nm to 500 nm is preferred, and 5 nm to 200 nm is more preferred. If it is 5 nm or larger, aggregation of inorganic particles can be suppressed, and the inorganic particles can be uniformly dispersed in the toner. If it is 500 nm or smaller, the heat resistance for storage can be improved due to the filler effect. The average particle diameter here is the value obtained by directly determining the particle diameter from the photograph obtained by transmission electron microscopy, and it is preferable to observe at least 100 particles and use the average value of their major axis.

[0083] <Developer> The toner of this embodiment can also be mixed with a carrier and used as a developer. In other words, the developer contains the toner of this embodiment and may also contain other components such as a carrier, as needed. By using this developer, a base layer with excellent adhesion properties can be formed on the surface of the fabric.

[0084] The developer may be a one-component developer or a two-component developer, but when used in high-speed printers and the like to accommodate the recent increase in information processing speed, a two-component developer is preferable from the standpoint of extending its lifespan.

[0085] When the toner of this embodiment is used as a one-component developer, even when the toner is balanced, there is little variation in the toner particle size, less toner filming onto the developing roller, and less toner fusion to components such as blades that thin the toner layer. As a result, good and stable developability and images can be obtained even with long-term agitation in the developing device.

[0086] The toner of this embodiment can be mixed with a carrier to form a two-component developer, which can then be used in a two-component electrophotographic image forming method. When the toner of this embodiment is used as a two-component developer, even with long-term toner balance cycles, the toner particle size remains stable, and good and stable developability and images can be obtained even with long-term agitation in the developing apparatus.

[0087] [Magnetic material] When using a two-component development method, there are no particular restrictions on the magnetic fine particles used as magnetic carriers, and they can be appropriately selected according to the purpose. Examples 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.), magnetoplanvite-type ferrite such as barium ferrite, and iron or alloy particles having an oxide layer on the surface. Among these, white ones are preferred in terms of color tone.

[0088] The shape of the magnetic nanoparticles may be granular, spherical, or needle-shaped. In particular, when high magnetization of the magnetic carrier is required, it is preferable to use ferromagnetic nanoparticles such as iron.

[0089] Furthermore, considering chemical stability, it is preferable to use magnetite, spinel ferrite containing gamma iron oxide, or magnetoplanbite-type ferrite such as barium ferrite. Specifically, MFL-35S, MFL-35HS (manufactured by Powdertech Co., Ltd.), DFC-400M, DFC-410M, SM-350NV (manufactured by Dowa Iron Powder Industry Co., Ltd.) are preferred.

[0090] By selecting the type and content of ferromagnetic fine particles (carriers), a resin carrier having a desired magnetization can also be used. For example, the magnetic properties of the above resin carrier are preferably such that the magnetization strength at 1,000 oorsted is 30 emu / g to 150 emu / g.

[0091] A resin carrier in which magnetic particles (carriers) are dispersed in a condensation-type binder can be produced by spraying a molten mixture of magnetic 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 particles.

[0092] The charge properties of a magnetic carrier can be controlled by fixing positively or negatively charged microparticles or conductive microparticles to the surface, or by coating it with a resin.

[0093] As the surface coating material (resin), silicone resin, acrylic resin, epoxy resin, fluororesin, etc., can be used, and the coating may further include positively or negatively charged fine particles or conductive fine particles, but among these, silicone resin and acrylic resin are preferred.

[0094] The mass ratio of carriers in the developer contained in the developing device is preferably 85% by mass or more and less than 98% by mass.

[0095] If the mass ratio of carriers in the developer is 85% by mass or higher, toner scattering from the developing device becomes less likely, reducing the occurrence of defective images. If the mass ratio of carriers in the developer is less than 98% by mass, it is possible to suppress excessive increases in the charge of the electrophotographic toner and insufficient supply of electrophotographic toner, thereby reducing the decrease in image density and the occurrence of defective images.

[0096] [Flow improver] A toner according to one embodiment may contain a fluidity improver as an additive. The fluidity improver is not particularly limited as long as it can be surface-treated to increase its hydrophobicity and prevent deterioration of fluidity or electrostatic properties even under high humidity conditions, and can be appropriately selected according to the purpose. Examples of fluidity improvers include silane coupling agents, silylation agents, silane coupling agents having alkyl fluoride, organic titanate coupling agents, aluminum coupling agents, silicone oil, and modified silicone oil.

[0097] It is preferable to surface-treat silica and titanium oxide, used as external additives, with such fluidity improvers and then use them as hydrophobic silica and hydrophobic titanium oxide, respectively.

[0098] [Cleaning performance enhancer] A toner according to one embodiment may contain a cleaning agent as an additive. The cleaning agent is not particularly limited as long as it can be added to the toner of this embodiment to remove the post-transfer developer remaining on the electrostatic latent image carrier or primary transfer medium, and can be appropriately selected according to the purpose. Examples of cleaning agents include fatty acid metal salts such as zinc stearate, calcium stearate, and stearic acid, polymer fine particles produced by soap-free emulsion polymerization such as polymethyl methacrylate fine particles and polystyrene fine particles. The polymer fine particles are preferably those with a relatively narrow particle size distribution, and preferably those with a volume average particle size of 0.01 μm or more and 1 μm or less.

[0099] <Toner manufacturing method> There are no particular restrictions on the toner manufacturing method, and it can be appropriately selected according to the purpose. An example of the toner manufacturing method of this embodiment is described below.

[0100] The toner manufacturing method of this embodiment may include, in one embodiment, a step of obtaining a binder resin mixture (mixing step), a step of obtaining a kneaded mixture (melt kneading step), a step of obtaining a solid of the kneaded mixture (solidification step), a step of obtaining a pulverized solid (fine grinding step), and a step of classifying and recovering the pulverized solid (classification step).

[0101] -Step to obtain a binder resin mixture (mixing step)- First, a binder resin, colorant, and release agent, along with any necessary static charge control agents, are mixed in a mixer to obtain a mixture (mixing step).

[0102] There are no particular restrictions on the type of mixer used; it can be selected appropriately depending on the purpose. Examples include the Henschel mixer (product name: FM20B, manufactured by Nippon Coke Industries Co., Ltd.) and the Super Mixer (SMV-20Ba, manufactured by Kawata Co., Ltd.).

[0103] -Step to obtain a kneaded mixture (melt kneading step)- Next, the obtained mixture is melt-kneaded using a hot-melt kneader to obtain a kneaded product (melt-kneading step).

[0104] There are no particular restrictions on the type of thermal melting kneader used, and they can be appropriately selected according to the purpose. Examples of product names include the twin-screw extruder PCM series (manufactured by Ikegai Co., Ltd.), the TEM type extruder (manufactured by Shibaura Machinery Co., Ltd.), the twin-screw extruder PCM Conneeder (manufactured by Buss Co., Ltd.), the open-roll type continuous kneader Needex (manufactured by Nippon Coke Industries Co., Ltd.), and the batch type kneader Wonder Kneader "WDS7-30" (manufactured by Moriyama Co., Ltd.).

[0105] -Process to obtain a solid product from the kneaded mixture (solidification process)- Next, the resulting mixture is cooled and solidified to obtain a solid (solidification step). There are no particular restrictions on the cooling method and solidification method, and they can be appropriately selected according to the purpose. For example, the molten mixture can be extruded through a 3 mm diameter die using a feeder-ruwer to form strands, cooled in a water bath at a water temperature of 15°C or lower, and the solidified strands can be cut with a pelletizer to obtain toner pellets.

[0106] -Process for obtaining pulverized solid material (fine grinding process)- Next, the obtained solid is finely pulverized to obtain pulverized material (fine pulverization step). The solid can be pulverized using known pulverization methods, such as the jet mill method, which pulverizes the solid using the energy when the toner is encapsulated in a high-speed airflow and collides with an impact plate; the interparticle collision method, which causes toner particles to collide with each other in an airflow; the mechanical pulverization method, which pulverizes the solid by supplying toner between a high-speed rotating rotor and a narrow gap; and the cyclone mill pulverization method, which generates a high-speed airflow by rotating two impellers and creates shear force. Since the toner of this embodiment is difficult to pulverize at room temperature, it is preferable to put the obtained solid (pellets) into a cooler and cool it with liquid nitrogen, and then pulverize it using the aforementioned mechanical pulverizer, cyclone mill pulverizer, or Linrex Mill LX (manufactured by Hosokawa Micron Corporation).

[0107] -The process of classifying and recovering the crushed material (classification process)- Next, the pulverized material is classified to recover material having a predetermined volume-average particle size. This allows to obtain toner (classification step). The classification method is not particularly limited and can be appropriately selected depending on the purpose; for example, any method can be used as appropriate.

[0108] Furthermore, the toner of this embodiment can be manufactured using the dissolution-suspension method. When manufacturing toner using the dissolution-suspension method, an oil phase is obtained by dissolving or dispersing toner materials such as a binder resin, colorant, release agent, and optionally a charge control agent in an organic solvent, and this oil phase is dispersed in an aqueous medium (aqueous phase), and the binder resin is reacted. This yields a dispersion containing a dispersion (oil droplets) that includes a prepolymer in which the toner materials have been emulsified or dispersed. Subsequently, the organic solvent is removed from the dispersion, and the material is filtered, washed, and dried, and further classification is performed as necessary to produce toner matrix particles. The toner of this embodiment can be obtained by granulating the matrix particles obtained using the dissolution-suspension method.

[0109] There are no particular restrictions on the organic solvent, and it can be appropriately selected depending on the purpose, but organic solvents with a boiling point of less than 150°C are preferred because they are easy to remove.

[0110] There are no particular restrictions on organic solvents with a boiling point below 150°C, and they can be appropriately selected depending on the purpose. Examples include toluene, xylene, benzene, carbon tetrachloride, methylene chloride, 1,2-dichloroethane, 1,1,2-trichloroethane, trichloroethylene, chloroform, monochlorobenzene, dichloroethylidene, methyl acetate, ethyl acetate, methyl ethyl ketone, and methyl isobutyl ketone. These may be used individually or in combination of two or more. Among these, ethyl acetate, toluene, xylene, benzene, methylene chloride, 1,2-dichloroethane, chloroform, and carbon tetrachloride are preferred, with ethyl acetate being more preferred.

[0111] There are no particular restrictions on the aqueous medium, and it can be appropriately selected depending on the purpose. Examples include water, a solvent miscible with water, or mixtures thereof. These may be used individually or in combination of two or more. Among these, water is preferred.

[0112] There are no particular restrictions on the solvent that can be miscible with water, and it can be appropriately selected depending on the purpose. Examples include alcohols, lower ketones, dimethylformamide, tetrahydrofuran, and cellosolves. There are no particular restrictions on the alcohol used; it can be selected appropriately depending on the purpose. Examples include methanol, isopropanol, and ethylene glycol. There are no particular restrictions on the lower ketones used; they can be appropriately selected depending on the purpose. Examples include acetone and methyl ethyl ketone.

[0113] There are no particular restrictions on the method for removing organic solvents from a dispersion, and a suitable method can be selected depending on the purpose. Examples include gradually raising the temperature of the entire reaction system to evaporate the organic solvent in the oil droplets, or spraying the dispersion into a dry atmosphere to remove the organic solvent from the oil droplets.

[0114] Classification in the dissolution-suspension method may be performed by removing fine particles in the liquid using a cyclone, decanter, centrifugation, etc., or by performing the classification operation after drying.

[0115] <Toner Set> The toner set of this embodiment refers to a set comprising a color toner containing a binder resin and a coloring agent, and the toner of this embodiment. As a result, the toner set of this embodiment can be sufficiently fixed to a flexible fiber medium such as cloth and can exhibit sufficient flexibility. Furthermore, the toner set of this embodiment can suppress the occurrence of screw lock.

[0116] There are no particular restrictions on the above-mentioned color toner, and a known color toner can be appropriately selected depending on the purpose. There are no particular restrictions on the binder resin contained in the color toner, and a known color agent can be appropriately selected depending on the purpose; for example, it can be the same as the binder resin contained in the toner of this embodiment. There are no particular restrictions on the colorant, and a known colorant can be appropriately selected depending on the purpose.

[0117] By installing the above toner set into the image forming apparatus described later and performing image formation, image formation is carried out using the toner of this embodiment, making it possible to perform image formation that takes advantage of the toner's characteristic of having excellent adhesion to fabric.

[0118] <Image Transfer Sheet> The image transfer sheet of this embodiment includes a release support and an image formed by the toner of this embodiment on the release support. As a result, the image transfer sheet of this embodiment allows the toner to be sufficiently fixed to a flexible fiber medium such as cloth and to exhibit sufficient flexibility.

[0119] The release support, which is the image transfer medium, can be any sheet-like material capable of forming an image. Specifically, examples of release supports include cardboard, postcards, roll paper, envelopes, plain paper, thin paper, coated paper (coated paper or art paper, etc.), tracing paper, OHP sheets, OHP films, resin films, etc., from which toner can be peeled off. The release support may also be a flexible recording medium such as cloth. Furthermore, from the viewpoint of releaseability, it is preferable that the release support has a release layer on its surface. It is preferable that the release support has a layer formed on its surface consisting of at least a silicone component or a fluorine component.

[0120] <Toner storage unit> The toner storage unit of this embodiment refers to a unit having the function of storing toner, in which the toner of this embodiment is stored. As a result, with the toner storage unit of this embodiment, the toner can be sufficiently fixed to a flexible fiber medium such as cloth and can exhibit sufficient flexibility. Furthermore, with the toner storage unit of this embodiment, the occurrence of screw lock can be suppressed.

[0121] Here, there are no particular restrictions on the form of the toner storage unit, and it can be appropriately selected according to the purpose. Examples include toner storage containers, developing units, and process cartridges.

[0122] A toner container refers to a container that holds toner. When toner is used as a developer, the toner container may be called a developer container. There are no particular restrictions on the type of developer container; any known container can be appropriately selected, such as one with a container body and a cap.

[0123] There are no particular restrictions on the size, structure, and material of the toner container and developer container; they can be appropriately selected according to the purpose.

[0124] The shape of the container body of the developer container is not particularly limited and can be appropriately selected according to the purpose, but it is preferable that it be cylindrical or tubular and have spirally formed irregularities on the inner circumference. Rotating the container body makes it easier to move the developer contents towards the outlet. Furthermore, it is more preferable that part or all of the irregularities are formed in a bellows shape. This makes it easier for the developer to move towards the outlet.

[0125] The material of the toner container and developer container is not particularly limited and can be appropriately selected according to the purpose, but it is preferable that it has good dimensional accuracy. Examples of materials include polyester resin, polyethylene resin, polypropylene resin, polystyrene resin, polyvinyl chloride resin, polyacrylic acid, polycarbonate resin, ABS resin, polyacetal resin, and other resin materials.

[0126] The toner and developer containers are easy to store, transport, and handle, and can be detachably attached to the image forming apparatus, process cartridge, etc., described later, for use in replenishing toner and developer.

[0127] A developing unit refers to a device that has means for storing and developing toner. A process cartridge refers to a device that integrates at least an electrostatic latent image carrier and means for developing, stores toner, and is detachable from an image forming apparatus. A process cartridge may further include at least one selected from means such as charging means, exposure means, and cleaning means.

[0128] By mounting the toner storage unit of this embodiment into the image forming apparatus of this embodiment and performing image formation, image formation is performed using the toner of this embodiment, thereby enabling image formation using a toner with excellent adhesion properties to fabric.

[0129] <Image forming method and image forming apparatus> The image forming apparatus of this embodiment includes an electrostatic latent image carrier, an electrostatic latent image forming unit for forming an electrostatic latent image on the electrostatic latent image carrier, a developing unit for developing the electrostatic latent image formed on the electrostatic latent image carrier with a developer containing the toner of this embodiment to form a toner image, a transfer unit for transferring the toner image formed on the electrostatic latent image carrier onto a peeling support or a flexible recording medium with a surface roughness of 1 μm or more, and a fixing unit for fixing the toner image transferred onto the peeling support or flexible recording medium. With this configuration, the image forming apparatus of this embodiment can sufficiently fix the toner to a medium made of flexible fibers such as cloth and exhibit sufficient flexibility. Furthermore, the image forming apparatus of this embodiment can suppress the occurrence of screw lock.

[0130] The image forming apparatus of this embodiment may further include other means as needed.

[0131] The image forming method of this embodiment comprises: an electrostatic latent image formation step of forming an electrostatic latent image on an electrostatic latent image carrier; a development step of developing the electrostatic latent image formed on the electrostatic latent image carrier with a developer containing the toner of this embodiment to form a toner image; a transfer step of transferring the toner image formed on the electrostatic latent image carrier onto a release support or a flexible recording medium with a surface roughness of 1 μm or more; and a fixing step of fixing the toner image transferred onto the release support or flexible recording medium. With this configuration, the image forming method of this embodiment allows the toner to be sufficiently fixed to a medium made of flexible fibers such as cloth and to exhibit sufficient flexibility. Furthermore, the image forming method of this embodiment can suppress the occurrence of screw lock.

[0132] In this embodiment, the image forming method is formed by the toner of this embodiment, and may include other steps as needed.

[0133] The image forming method can be suitably carried out by the image forming apparatus of this embodiment, the electrostatic latent image formation step can be suitably carried out by the electrostatic latent image formation unit of this embodiment, the development step can be suitably carried out by the development unit of this embodiment, the transfer step can be suitably carried out by the transfer unit of this embodiment, the fixing step can be suitably carried out by the fixing unit of this embodiment, and other steps can be suitably carried out by other means of this embodiment.

[0134] [Electrostatic latent image carrier] There are no particular restrictions on the structure and size of the electrostatic latent image carrier, and they can be appropriately selected from known types depending on the purpose. There are no particular restrictions on the material of the electrostatic latent image carrier, and it can be appropriately selected according to the purpose. Examples include inorganic photoreceptors such as amorphous silicon and selenium, and organic photoreceptors (OPC) such as polysilane and phthalopolymethine.

[0135] There are no particular restrictions on the shape of the electrostatic latent image carrier, and it can be appropriately selected according to the purpose, but a cylindrical shape is preferred. There are no particular restrictions on the outer diameter of the cylindrical electrostatic latent image carrier, and it can be appropriately selected according to the purpose, but it is preferably 3 mm to 100 mm, more preferably 5 mm to 50 mm, and even more preferably 10 mm to 30 mm.

[0136] [Electrostatic latent image formation section and electrostatic latent image formation process] The electrostatic latent image forming unit 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 according to the purpose. The electrostatic latent image forming unit may, for example, include a charging device for uniformly charging the surface of the electrostatic latent image carrier and an exposure device for exposing the surface of the electrostatic latent image carrier to an image. The electrostatic latent image formation step in this embodiment is a step of forming an electrostatic latent image on an electrostatic latent image carrier, and may 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 form an electrostatic latent image.

[0137] There are no particular restrictions on the charging process, and it can be appropriately selected depending on the purpose. For example, it can be carried out by applying a voltage to the surface of the electrostatic latent image carrier using a charging device.

[0138] There are no particular restrictions on exposure, and it can be appropriately selected depending on the purpose. For example, it can be performed by exposing the surface of the electrostatic latent image carrier to an image using an exposure apparatus.

[0139] The formation of the electrostatic latent image is not particularly limited and can be appropriately selected depending on the purpose. For example, it can be performed by uniformly charging the surface of the electrostatic latent image carrier and then exposing it in an image-like manner, and this can be done by an electrostatic latent image forming unit.

[0140] -Charging device- There are no particular restrictions on the charging device, and it can be appropriately selected according to the purpose. Examples include contact chargers equipped with conductive or semiconductive rolls, brushes, films, rubber blades, etc., and non-contact chargers that utilize corona discharge, such as Corotron and Scorotron.

[0141] The charging device can take any form other than a roller, such as a magnetic brush or a fur brush, and can be selected according to the specifications or form of the image forming apparatus.

[0142] Preferably, the charging device is positioned in contact with or without contact with the electrostatic latent image carrier, and charges the surface of the electrostatic latent image carrier by superimposing DC and AC voltages. Alternatively, it is preferable that the charging device is a charging roller positioned in close proximity to the electrostatic latent image carrier via a gap tape, and charges the surface of the electrostatic latent image carrier by superimposing DC and AC voltages on the charging roller.

[0143] While the charging device is not limited to a contact-type charging device, it is preferable to use a contact-type charging device because it allows for the creation of an image forming apparatus with reduced ozone generation from the charging device.

[0144] -Exposure equipment- There are no particular restrictions on the exposure apparatus as long as it can expose the surface of an electrostatic latent image carrier, which has been charged by a charging device, in the manner of the image to be formed. It can be appropriately selected according to the purpose, and examples of such apparatus include various exposure apparatuses such as copying optical systems, rod lens array systems, laser optical systems, and liquid crystal shutter optical systems.

[0145] There are no particular restrictions on the light source used in an exposure apparatus, and it can be appropriately selected according to the purpose. Examples include fluorescent lamps, tungsten lamps, halogen lamps, mercury lamps, sodium lamps, light-emitting diodes (LEDs), semiconductor lasers (LDs), electroluminescent devices (ELs), and other types of light-emitting materials.

[0146] Furthermore, various filters such as sharp-cut filters, band-pass filters, near-infrared cut filters, dichroic filters, interference filters, and color temperature conversion filters can be used to illuminate only the desired wavelength range.

[0147] Alternatively, a back-facing method may be employed in which the electrostatic latent image carrier is exposed in an image-like manner from the back side.

[0148] [Developing section and developing process] The developing unit 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 according to the purpose. The developing unit can preferably be one equipped with a developer that contains toner and can apply toner to the electrostatic latent image by contact or non-contact, and a developer equipped with a toner container is preferred.

[0149] The development step in the image forming method of this embodiment is a step of sequentially developing an electrostatic latent image with multiple colors of toner to form a toner image. The formation of the toner image can be performed, for example, by developing the electrostatic latent image using toner, and this can be done using a developer.

[0150] The toner of this embodiment is used in the developing section and the developing process. Preferably, a developer containing the toner of this embodiment, and optionally containing other components such as a carrier, may be used to form the toner image.

[0151] The developing unit may be a single-color developing unit or a multi-color developing unit. A preferred developing device has, for example, an agitator that frictionally agitates and charges the toner, a magnetic field generating unit fixed inside, and a rotatable developer carrier on which a developer containing toner is carried on its surface.

[0152] Inside the developing unit, for example, toner and carrier are mixed and stirred, and the friction during this process causes the toner to become charged. This charge is then held in a pile-like state on the surface of the rotating magnetic roller, forming a magnetic brush. Since the magnetic roller is positioned near the electrostatic latent image carrier, some of the toner that makes up the magnetic brush formed on the surface of the magnetic roller is moved to the surface of the electrostatic latent image carrier by electrical attraction. As a result, the electrostatic latent image is developed by the toner, and a toner image is formed on the surface of the electrostatic latent image carrier.

[0153] The image forming apparatus of this embodiment may be equipped with a total of five developing units: a developing unit for color toners (for black, cyan, magenta, and yellow) and a developing unit for the toner of this embodiment. The toner of this embodiment may be of any color, but it is preferably colorless or white. The toner used in the developing unit may consist of some or all of the black, cyan, magenta, and yellow color toners, which may be the toner of this embodiment.

[0154] [Transfer section and transfer process] The transfer unit preferably comprises a primary transfer unit that transfers a toner image onto an intermediate transfer unit to form a composite transfer image, and a secondary transfer unit that transfers the composite transfer image onto a peeling support or a flexible recording medium. The intermediate transfer unit is not particularly limited and can be appropriately selected from known transfer units depending on the purpose; for example, a transfer belt is a suitable example.

[0155] The transfer step in the image forming apparatus of this embodiment is a step of transferring a toner image onto a peeling support or a flexible recording medium. In this transfer step, it is preferable to use an intermediate transfer body, to first transfer the toner image onto the intermediate transfer body, and then secondarily transfer the toner image onto the peeling support or the flexible recording medium.

[0156] The transfer process more preferably includes a first transfer step in which two or more toners, preferably full-color toners, are used to transfer a toner image onto an intermediate transfer body to form a composite transfer image, and a second transfer step in which the composite transfer image is transferred onto a peeling support or a flexible recording medium.

[0157] Transfer can be performed, for example, by charging an electrostatic latent image carrier with a toner image using a transfer charging device, and can be carried out by a transfer unit.

[0158] The transfer section (primary transfer section and secondary transfer section) preferably includes at least a transfer device that discharges and charges the toner image formed on the electrostatic latent image carrier toward the peeling support side or the flexible recording medium side. The transfer section may be one or two or more.

[0159] Examples of transfer components include corona discharge transfer devices, transfer belts, transfer rollers, pressure transfer rollers, and adhesive transfer devices.

[0160] While release paper is a typical support material for release, there are no particular restrictions as long as it can transfer the unfixed image after development. It can be appropriately selected according to the purpose, and plain paper or PET base for OHP can also be used.

[0161] While cloth is a typical example of a flexible recording medium with a surface roughness of 1 μm or more, there are no particular restrictions as long as it can transfer the unfixed image after development, and it can be appropriately selected according to the purpose. Examples include woven fabrics or nonwoven fabrics made of fibers.

[0162] The image thickness printed on the release support or flexible recording medium is preferably 50 μm to 150 μm, and particularly preferably 50 μm to 100 μm. If the image thickness is less than 50 μm, cracking is likely to occur due to the expansion and contraction of the image. If it is thicker than 150 μm, the image becomes rigid, and when printed on clothing such as T-shirts, the rigidity of the image area will cause a strong feeling of discomfort when worn. Also, if the image thickness is thicker than 150 μm, the toner is more likely to be offset. The image thickness can be measured by magnifying and photographing the cross-section of the image with a microscope.

[0163] [Fixing section and fixing process] There are no particular restrictions on the fixing section, and it can be appropriately selected according to the purpose, but a known heating and pressing section is preferred. Examples of such heating and pressing sections include a combination of a heating roller and a pressing roller, and a combination of a heating roller, a pressing roller and an endless belt.

[0164] The fixing step in the image forming apparatus of this embodiment is a step of fixing the toner image transferred onto the peeling support or flexible recording medium using a fixing device. This step may be performed for each color developer after the transfer onto the peeling support or flexible recording medium, or it may be performed simultaneously for each color developer in a laminated state.

[0165] Preferably, the fixing section is a heating and pressing section that includes a heating element equipped with a heating element, paper or release paper in contact with the heating element, and a pressing member that presses against the heating element via the paper or release paper, and can heat and fix the film by passing it through a release support or flexible recording medium on which an unfixed image has been formed between the film and the pressing member.

[0166] The heating temperature in the heating and pressurizing section is not particularly limited and can be appropriately selected depending on the purpose, but 80°C to 200°C is preferred.

[0167] There are no particular restrictions on the surface pressure in the heating and pressurizing section, and it can be appropriately selected depending on the purpose, but 10 N / cm is recommended. 2 More than 80N / cm 2 The following is preferable:

[0168] In this embodiment, depending on the purpose, a fixing means such as a known optical fixing device may be used together with or in place of the fixing unit.

[0169] In addition to the fixing unit in the image forming apparatus, commercially available household irons or commercial iron presses (such as the manual heat press machine PHP-MS233 from Piotec Corporation) may be used as the fixing unit. In this case, during the fixing process, a medium such as fabric is placed on top of the toner image on the release support, and then release paper is placed on top of that, and heat and pressure are applied. The appropriate values ​​for heat and pressure are selected based on the thermal characteristics of the toner, the type of fabric, and the thickness of the fabric. Subsequently, the release paper and release support are peeled off, and the toner image is heat-transferred and fixed onto the fabric such as cloth. After that, if necessary, release paper is placed on top of the toner image, and heat and pressure are applied again to final fix the toner image.

[0170] [Other means and other processes] In addition to the above configuration, the image forming apparatus of this embodiment may include other means as needed, such as a static elimination unit, a cleaning unit, a recycling unit, a control unit, and so on.

[0171] In addition to the above configuration, the image forming method of this embodiment may include other steps as appropriate, such as a static elimination step, a cleaning step, a recycling step, etc.

[0172] [Static elimination unit and static elimination process] The static elimination unit is not particularly limited as long as it can apply a static elimination bias to the electrostatic latent image carrier, and can be appropriately selected from known static elimination means depending on the purpose. For example, a static elimination lamp is a suitable example.

[0173] The static elimination process involves applying a static elimination bias to the electrostatic latent image carrier to remove static electricity, and this process can be more effectively performed by the static elimination unit.

[0174] [Cleaning section and cleaning process] The cleaning unit is not particularly limited as long as it can remove toner remaining on the electrostatic latent image carrier, and can be appropriately selected from known cleaners according to the purpose, such as magnetic brush cleaners, electrostatic brush cleaners, magnetic roller cleaners, blade cleaners, brush cleaners, and web cleaners.

[0175] The cleaning process is a process of removing toner remaining on the electrostatic latent image carrier, and can be performed more effectively by the cleaning unit.

[0176] The image forming apparatus of this embodiment can improve cleaning performance by having a cleaning unit. Specifically, by controlling the adhesion force between toners, the fluidity of the toner can be controlled, thereby improving cleaning performance.

[0177] Furthermore, by controlling the characteristics of the toner after degradation, it is possible to extend its lifespan or maintain excellent cleaning quality even under harsh conditions such as high temperature and humidity. In addition, since the external additive can be sufficiently released from the toner on the electrostatic latent image carrier, a deposit layer (dam layer) of the external additive can be formed in the cleaning blade nip, thereby achieving high cleaning performance.

[0178] [Recycling Department and Recycling Process] There are no particular restrictions on the recycling department; it can be selected appropriately according to the purpose, for example, known means of transport.

[0179] The recycling process involves recycling the toner removed during the cleaning process into the developing unit, and can be performed more effectively in the recycling unit.

[0180] [Control Unit] The control unit can control the movement of each of the above-mentioned parts. As long as the control unit can control the movement of each of the above-mentioned parts, there are no particular restrictions, and it can be appropriately selected according to the purpose. Examples include control devices such as sequencers and computers.

[0181] Since the image forming apparatus of this embodiment can perform image formation using the toner of this embodiment, it can provide images with excellent fixability to flexible media such as cloth, reduce power consumption, and stably provide high-quality images.

[0182] The image forming method of this embodiment can perform image formation using the toner of this embodiment, and can provide images with excellent fixability on flexible media such as cloth, and can also stably provide high-quality images.

[0183] Herein, one aspect of the image forming apparatus of this embodiment will be described with reference to Figure 1. However, the present invention is not limited in any way to these embodiments. In each drawing, the same reference numerals are used for the same components, and redundant descriptions may be omitted. Furthermore, the number, position, shape, etc. of the following components are not limited to this embodiment, and can be set to a number, position, shape, etc. that is preferable for carrying out the image forming apparatus of this embodiment.

[0184] Figure 1 is a schematic diagram showing an example of an image forming apparatus according to one embodiment of the present invention. In Figure 1, the toner developing unit of this embodiment is omitted, but the toner developing unit of this embodiment is provided in the same way as the developing units for other colored toners (see Figure 3). For convenience, Figure 1 will be described assuming that it includes the toner image forming unit 20A, the photoreceptor drum 4A which is an electrostatic latent image carrier, and the primary transfer roller 61A of this embodiment.

[0185] The image forming apparatus shown in Figure 1 is a so-called tandem-type image forming apparatus in which five toner image forming units 20Y, 20C, 20M, 20K, and 20A for yellow, cyan, magenta, black, and white toners are arranged in parallel, and the toner images of each color (yellow (Y), cyan (C), magenta (M), black (K), and white (A)) formed by each toner image forming unit are superimposed to form a full-color image. There are no particular restrictions on the arrangement of the toner image forming units for each color.

[0186] Each toner image forming unit 20Y, 20C, 20M, 20K, and 20A is equipped with a photoreceptor drum 4Y, 4C, 4M, 4K, and 4A, respectively, which is rotated as an electrostatic latent image carrier. An exposure device 45 is also provided for each photoreceptor drum 4Y, 4C, 4M, 4K, and 4A, which is exposed to laser light or LED light based on image information for each color to form a latent image.

[0187] Furthermore, an intermediate transfer belt 60 is arranged to move on the surface so as to face each toner image forming section 20Y, 20C, 20M, 20K, and 20A. Primary transfer rollers 61Y, 61C, 61M, 61K, and 61A are positioned opposite the photoreceptor drums 4Y, 4C, 4M, 4K, and 4A via the intermediate transfer belt 60 to transfer the toner images of each color formed on the photoreceptor drums 4Y, 4C, 4M, 4K, and 4A to the intermediate transfer belt 60.

[0188] The primary transfer rollers 61Y, 61C, 61M, 61K, and 61A sequentially transfer the toner images of each color formed by the respective toner image forming units 20Y, 20C, 20M, 20K, and 20A (described later) onto the intermediate transfer belt 60, and superimpose them to form a full-color image.

[0189] Furthermore, downstream of the primary transfer rollers 61Y, 61C, 61M, 61K, and 61A in the surface movement direction of the intermediate transfer belt 60, a secondary transfer device 65 is arranged to transfer the toner image on the intermediate transfer belt 60 to the transfer medium in one go. Further downstream of the secondary transfer device 65, a belt cleaning device 66 is provided to remove toner remaining on the surface of the intermediate transfer belt 60.

[0190] At the bottom of the image forming apparatus is a paper feeding section 70 consisting of a paper feed cassette 71, paper feed rollers 72, etc., which feeds the transfer medium toward the register roller 73. The register roller 73 feeds the transfer medium toward the opposing section between the intermediate transfer belt 60 and the secondary transfer device 65 in accordance with the timing of toner image formation. The full-color toner image on the intermediate transfer belt 60 is transferred onto the transfer medium by the secondary transfer device 65, fixed by the fixing device 90, and then discharged outside the machine.

[0191] Next, we will describe each toner image forming unit 20Y, 20C, 20M, 20K, and 20A. Since each toner image forming unit 20Y, 20C, 20M, 20K, and 20A has almost the same configuration and operation except for the color of the toner it contains, the subscripts Y, C, M, K, and A used for color differentiation will be omitted in the following description, and the configuration and operation of the toner image forming unit 20' will be described. Figure 2 is a schematic diagram showing the main components of an example of an image forming apparatus according to one embodiment of the present invention.

[0192] Around the photoreceptor drum 4' of the toner image forming unit 20', various components that perform the electrophotographic process, such as a charging device 40', a developing device 50, and a cleaning device 30', are arranged, and in known operation, toner images of each color are formed on the photoreceptor drum 4', which is an electrostatic latent image carrier. Such a toner image forming unit 20' may be an integrally formed process cartridge that can be attached to and detached from the main body of the image forming apparatus.

[0193] Figure 3 is a schematic diagram showing the main components of an example of an image forming apparatus according to one embodiment of the present invention. Explanations of aspects similar to those of the image forming apparatus described above will be omitted.

[0194] The image forming apparatus of this embodiment includes a photoreceptor (photoreceptor 5, photoreceptor 11, photoreceptor 17, photoreceptor 23, photoreceptor 29) which is an electrostatic latent image carrier, and surrounding the photoreceptor are a charger (charger 6, charger 12, charger 18, charger 24, charger 30) which is a charging device, a developing unit (developing unit 8, developing unit 14, developing unit 20, developing unit 26, developing unit 32), a transfer unit (transferrer 10, transferr 16, transferr 22, transferr 28, transferr 34), and a cleaning device (cleaning device 9, cleaning device 15, cleaning device 21, cleaning device 27, cleaning device 33), and the photoreceptor is irradiated with exposure light (exposure light 7, exposure light 13, exposure light 19, exposure light 25, exposure light 31).

[0195] Each color developing unit is equipped with a photoreceptor, charger, developing section, cleaning device, etc. Developing unit 35 uses the toner of this embodiment, developing unit 36 ​​uses black toner, developing unit 37 uses cyan toner, developing unit 38 uses magenta toner, and developing unit 39 uses yellow toner to create images, which are then transferred to the intermediate transfer belt 40 for further image formation.

[0196] The image formed on the intermediate transfer belt 40 is transferred to the transfer medium by the transfer device 41 and fixed by the fixing device 43. A paper feed cassette 1 and a paper feed roller 2 are provided at the bottom of the developing unit, which feed the transfer medium toward the registration rollers 3 and 4. The registration rollers 3 and 4 feed the transfer medium toward the opposing part between the intermediate transfer belt 40 and the transfer device 41 in accordance with the timing of toner image formation.

[0197] Furthermore, it is preferable that the toner image in this embodiment is formed closest to the transfer medium. The transfer medium is preferably a peeling support, but may also be a flexible recording medium.

[0198] <Method for thermal transfer and fixing toner images onto media such as fabric> Next, we will explain a method for thermally transferring and fixing the toner image formed on the release support using the method described above to a final medium such as cloth.

[0199] Toner is repeatedly printed onto an image printed on a release support until the toner reaches a predetermined thickness. This image thickness is preferably 50 μm to 150 μm, and particularly preferably 50 μm to 100 μm. If the image thickness is less than 50 μm, cracking is more likely to occur due to image expansion and contraction; if it is thicker than 150 μm, the image becomes rigid, leading to a greater feeling of discomfort due to the stiffness of the image when worn. Furthermore, the toner is more prone to offsetting. The image thickness can be measured by magnifying and photographing a cross-section of the image with a microscope.

[0200] A medium such as fabric is placed on top of the toner image on the release support, and release paper is placed on top, then heat and pressure are applied. A commercially available household iron or a commercial iron press (such as the PHP-MS233 manual heat press from Piotec) can be used for this. The heat and pressure applied should be selected based on the thermal characteristics of the toner, the type of fabric, and the thickness of the fabric. Next, the release paper and release support are peeled off, and the toner image is heat-transferred and fixed onto the fabric.

[0201] Afterward, if necessary, release paper is placed over the toner image, and heat and pressure are applied again to finish and fix the toner image. [Examples]

[0202] The embodiments will be described in more detail below with reference to examples and comparative examples, but the embodiments are not limited to these.

[0203] [Example 1] (Toner production) -raw materials- • Polyurethane resin ECOFREEN POWDER (manufactured by ECOFREEN, glass transition temperature -29°C, Mw 47000, components: 1,4-butanediol, adipic acid, diphenylmethane diisocyanate) 52% by mass • Polyester resin RN-306SF (manufactured by Kao Corporation) 18% by mass • Wax dispersant EXD-001 (manufactured by Sanyo Chemical Industries, Ltd.) 2.5% by mass • Ester wax LW-13 (manufactured by Sanyo Chemical Industries) 2.5% by mass • Titanium dioxide white pigment PF-739 (manufactured by Ishihara Sangyo Co., Ltd.) 25% by mass

[0204] The above raw materials were pre-mixed using a Henschel mixer (FM20B, manufactured by Nippon Coke Industries Co., Ltd.), and then melted and kneaded at a temperature of 90°C using a batch-type kneader (Wonder Kneader "WDS7-30", manufactured by Moriyama Co., Ltd.). The resulting kneaded material was extruded through a 3mm diameter die using a feeder-luderer to form strands, which were then cooled and solidified in a water bath at a water temperature of 15°C or lower. The solidified strands were cut with a pelletizer to obtain toner pellets with a diameter of 2mm and a length of 2mm. These toner pellets are the coarsely ground molten kneaded toner components.

[0205] Next, the toner pellets were placed in a cooler and cooled with liquid nitrogen, then pulverized using a mechanical pulverizer (Hosokawa Micron, Linlex Mill LX). The pulverized material was sieved through a 37 μm mesh, and any unpassed particles were reintroduced to the pulverizer to obtain fine particles that passed through the 37 μm mesh.

[0206] After the fine particles that passed through the 37 μm mesh were returned to room temperature, they were classified into fine particles using an airflow classifier (Matsubo Co., Ltd., EJ-LABO) while appropriately adjusting the louver opening so that the percentage of particles with a volume average particle size of 5 μm or less was less than 10 percent, thereby obtaining toner matrix particles.

[0207] Next, 1.0 part by mass of additive 1 (HDK-2000, manufactured by Clariant, substance name: silica) and 1.0 part by mass of additive 2 (H05TD, manufactured by Clariant, substance name: silica) were mixed together in a Henschel mixer to produce the toner of Example 1.

[0208] (Manufacturing of two-component developers) ((Career creation)) Silicone resin (organostraight silicone) 100 parts by mass Toluene 100 parts by mass 5 parts by mass of γ-(2-aminoethyl)aminopropyltrimethoxysilane Carbon black 10 parts by mass The above mixture was dispersed in a homomixer for 20 minutes to prepare a coating layer forming solution. This coating layer-forming liquid was applied using a fluidized bed coating apparatus, with the temperature in the fluidized tank controlled to 70°C, to achieve an average film thickness of 0.20 μm on the surface of Mn ferrite particles with a weight-average particle size of 35 μm as the core material, and then dried. The obtained carrier was calcined in an electric furnace at 180°C for 2 hours to obtain carrier A.

[0209] ((Preparation of two-component developer)) The toner prepared in Example 1 and carrier A were uniformly mixed and charged using a turbler mixer (manufactured by Willy e Bakkofen (WAB)) at 48 rpm for 5 minutes to prepare the two-component developer of Example 1. The mixing ratio of toner to carrier was adjusted to match the toner concentration of the initial developer of the evaluation machine: 7% by mass.

[0210] [Example 2] -raw materials- • Polyurethane resin ECOFREEN POWDER (manufactured by ECOFREEN, glass transition temperature -29°C, Mw 47000, components: 1,4-butanediol, adipic acid, diphenylmethane diisocyanate) 75% by mass • Polyester resin RN-306SF (manufactured by Kao Corporation) 5% by mass • Wax dispersant EXD-001 (manufactured by Sanyo Chemical Industries, Ltd.) 2.5% by mass • Ester wax LW-13 (manufactured by Sanyo Chemical Industries) 2.5% by mass • Titanium dioxide white pigment PF-739 (manufactured by Ishihara Sangyo Co., Ltd.) 15% by mass. The toner and two-component developer of Example 2 were prepared in the same manner as in Example 1, except that the above raw materials were used.

[0211] [Example 3] -raw materials- • Polyurethane resin (manufactured by DIC Covestropolymer, glass transition temperature -36°C, Mw 127000, constituent components: 1,4-butanediol, adipic acid, diphenylmethane diisocyanate) 55% by mass • Polyester resin RN-306SF (manufactured by Kao Corporation) 5% by mass • Wax dispersant EXD-001 (manufactured by Sanyo Chemical Industries, Ltd.) 2.5% by mass • Ester wax LW-13 (manufactured by Sanyo Chemical Industries) 2.5% by mass • Titanium dioxide white pigment PF-739 (manufactured by Ishihara Sangyo Co., Ltd.) 35% by mass The toner and two-component developer of Example 3 were prepared in the same manner as in Example 1, except that the raw materials listed above were used.

[0212] [Example 4] -raw materials- • Polyurethane resin (manufactured by DIC Covestropolymer, glass transition temperature -36°C, Mw 127000, constituent components: 1,4-butanediol, adipic acid, diphenylmethane diisocyanate) 51% by mass • Polyester resin RN-306SF (manufactured by Kao Corporation) 4% by mass • Wax dispersant EXD-001 (manufactured by Sanyo Chemical Industries, Ltd.) 2.5% by mass • Ester wax LW-13 (manufactured by Sanyo Chemical Industries) 2.5% by mass • Titanium dioxide white pigment PF-739 (manufactured by Ishihara Sangyo Co., Ltd.) 40% by mass The toner and two-component developer of Example 4 were prepared in the same manner as in Example 1, except that the raw materials listed above were used.

[0213] [Comparative Example 1] -raw materials- • Polyurethane resin ECOFREEN POWDER (manufactured by ECOFREEN, glass transition temperature -29°C, Mw 47000, components: 1,4-butanediol, adipic acid, diphenylmethane diisocyanate) 35% by mass • Polyester resin RN-306SF (manufactured by Kao Corporation) 5% by mass • Wax dispersant EXD-001 (manufactured by Sanyo Chemical Industries, Ltd.) 2.5% by mass • Ester wax LW-13 (manufactured by Sanyo Chemical Industries) 2.5% by mass • Titanium dioxide white pigment PF-739 (manufactured by Ishihara Sangyo Co., Ltd.) 55% by mass The toner and two-component developer of Comparative Example 1 were prepared in the same manner as in Example 1, except that the above raw materials were used.

[0214] The characteristics of the toners from Examples 1-4 and Comparative Example 1 were evaluated as follows. The results are shown in Table 1.

[0215] <Measurement of true toner density> The true density of the toner was measured using the Accupic II 1340 unit (manufactured by Shimadzu Corporation). The results are shown in Table 1.

[0216] <Measurement of average circularity of toner The average circularity of the toner was measured using a flow-type particle image analyzer (FPIA®-3000, manufactured by Sysmex Corporation). 0.1 ml to 0.5 ml of 10% by mass of surfactant (alkylbenzenesulfonate, Neogen® SC-A, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) was added to a 100 ml glass beaker, 0.1 g to 0.5 g of toner was added, and the mixture was stirred using a micro spatula. 80 ml of deionized water was then added to obtain a dispersion.

[0217] The obtained dispersion was subjected to ultrasonic dispersion treatment (manufactured by Honda Electronics Co., Ltd.) for 3 minutes to obtain the measurement sample. The average circularity of the toner was measured using analysis software (FPIA(registered trademark)-3000) until the toner particle concentration reached 5,000 particles / μL to 15,000 particles / μL. The results are shown in Table 1.

[0218] <Measurement of volume-average particle size of toner> The volume-average particle size of the toner was measured using a laser diffraction particle size distribution analyzer ("SALD-2300", manufactured by Shimadzu Corporation). 0.5 ml of 10% by mass surfactant (alkylbenzenesulfonate, Neogen® SC-A, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) was added to a 100 ml glass beaker, 2 g to 4 g of toner was added and stirred with a micro spatula, and 80 ml of deionized water was added to obtain a dispersion.

[0219] The obtained dispersion was subjected to dispersion treatment for 10 minutes using an ultrasonic disperser (W-113MK-II, manufactured by Honda Electronics Co., Ltd.) to obtain the measurement sample. The volume-average particle size of the measurement sample was measured using a laser diffraction particle size distribution analyzer. The results are shown in Table 1.

[0220] <Measurement of toner looseness and apparent bulk density> A graduated cylinder with a stopper, whose weight was measured in advance: 50 cm 3 14g of toner was added to (±0.25ml (TC20℃)). Next, the toner was mixed by hand, shaking the stoppered graduated cylinder 10 times. Then, it was left to stand for 10 minutes and the toner volume was determined. The value calculated based on the above formula (1) was then taken as the loose apparent bulk density. The results are shown in Table 1.

[0221] <Measurement of toner softening temperature Ts> For measuring the softening temperature, a flow tester (Shimadzu Corporation, CFT-500D) was used. Toner was pressure-molded into tablets at the lowest possible pressure to form pellets. These pellets were stored in an 80°C constant temperature bath for 30 minutes, and then allowed to cool naturally to room temperature. The toner samples were used, and the flow tester softening temperature (Ts) was measured. The toner's flow tester softening temperature (Ts) was determined from the flow curve measured using an elevated flow tester, model CFT500 (Shimadzu Corporation). The measurement conditions are as follows: Sample quantity: 1.00 ± 0.05 g Starting temperature 40℃ Achieved temperature 200℃ Heating rate: 3.0℃ / min Test load: 35 kgf Die hole diameter 0.5mm Die length 1.0mm

[0222] In addition, if the shoulder of the piston stroke curve corresponding to Ts does not appear in the measurement using the flow tester described above, Ts is not automatically detected by the software included with the flow tester. In this case, Ts was set to less than 40°C. The results are shown in Table 1.

[0223] <Observation of toner cross-section (coarsely ground toner component molten mixture)> The presence or absence of sea-island structures in toner was confirmed by observing backscattered electron images of the particle cross-section of the crushed molten toner component mixture of each toner using a scanning electron microscope (SEM). The difference in color between polyester and urethane confirmed the presence of sea and island regions (incompatible domains).

[0224] To enhance contrast and facilitate the distinction between island and sea areas, staining with ruthenium tetroxide (substance name: ruthenium tetroxide, manufactured by TAAB) was performed as needed. For each ruthenium-stained molten toner compound, SEM images of the particle cross-section of the molten toner compound at approximately half the particle size were taken under the following conditions to confirm the presence or absence of sea-island structures. The procedure is as follows.

[0225] The coarsely ground toner components of each toner were embedded in epoxy resin and observed using a scanning electron microscope (Hitachi, Ltd., SU8230) under the following conditions. In this case, the unstained areas were observed as dark areas, making it possible to distinguish them from the stained areas (bright areas). • Acceleration voltage: 5kV • Emission current: 10μA • Probe current: Norm • Condenser lens 1:5.0 WD: 8.0mm • Observation mode: SE Magnification: ×2,000 or ×5,000

[0226] Figure 4 shows an average cross-sectional SEM image of the crushed toner component molten mixture of the toner from Example 1. The entire region indicated by "100" in Figure 4 is a domain (island). While such a sea-island structure was confirmed in the cross-sections of the crushed toner component molten mixture of the toners from Examples 1 to 4, no sea-island structure was confirmed in the cross-section of the crushed toner component molten mixture of the toner from Comparative Example 1.

[0227] <Screwlock Resistance Evaluation> Screw lock resistance tests were conducted using the toners and two-component developers of Examples 1-4 and Comparative Example 1 as described below, and screw lock resistance was evaluated based on the following criteria. (1) Place the toner into the Y-station toner bottle of the RICOH IMC2500 (manufactured by Ricoh) and set it in the machine. Then, set the two-component developer using the same toner into the RICOH IMC2500 (manufactured by Ricoh) Y-station developing machine, and the toner adhesion amount is 0.45 mg / cm². 2 The development and transfer conditions were adjusted using a process controller, and 500 full-surface solid toner images were printed on Ricoh MyPaper A3 PPC. Of the evaluation results below, A and B were judged to be feasible as toners for this embodiment. The results are shown in Table 1. [Evaluation Criteria] A: No abnormal images were found, and the screw inside the sub-hopper was also normal. B: Image density gradually decreases, small clumps form in the screw part inside the sub-hopper, and the supply rate is insufficient, so it is necessary to stop printing periodically and forcibly replenish the toner. C: The image density gradually decreases, many clumps form in the screw part inside the sub-hopper, and eventually the screw becomes solidified with toner, forcing the experiment to be interrupted.

[0228] <Image robustness evaluation> The toner images were heat-transferred onto fabric using the two-component developers of Examples 1-4 and Comparative Example 1, and the image fastness of each fixed image was evaluated. (1) Set each two-component developer in the 5th station of the RICOH Pro C7200S (manufactured by Ricoh), and set the toner adhesion amount to 1.0 mg / cm².2 The developing and transfer conditions were adjusted by the process controller so as to achieve this. Then, as the peeling support, a solid image of toner was output onto the image layer forming region on a release paper (trade name: WoW Light 8.0, manufactured by Pyotec Co., Ltd.) having a layer made of a silicone component (silicone surface layer) formed on its surface. (2) Next, the toner image transferred to the release paper was fixed to prepare an image transfer sheet. As a result of magnifying and photographing the cross-section of the toner image on the release paper using a microscope and measuring the image thickness, it was the thickness shown in Table 1. (3) A 100% polyester cloth was laid over the toner image on the release paper, and an iron at 160 °C was applied with a load of 600 g / cm 2 for 10 seconds to thermally transfer the toner image onto the cloth to produce a fixed image for evaluation.

[0229] After repeating the washing and drying of the fixed image 10 times, the fixed image was visually checked to see if it broke when stretched by about 1 cm by hand, and the image fastness was evaluated based on the following criteria. Among the following evaluation results, A to C were judged to be feasible as the toner of the present embodiment. The results are shown in Table 1. 〔Evaluation Criteria〕 A: No breakage of the fixed image B: 1 to 4 breakages occurred in the fixed image C: 5 or more breakages occurred in the fixed image

[0230]

Table 1

[0231] The toners of Examples 1 to 4 were shown to be feasible as the toners of the present embodiment because the evaluation results of the image fastness were A or B and the evaluation results of the screw lock resistance were A or B. On the other hand, the toner of Comparative Example 1 was shown to be infeasible as the toner of the present embodiment because both the evaluation result of the image fastness and the evaluation result of the screw lock resistance were C.

[0232] (Aspect of the present invention) The present invention includes the following embodiments. <Aspect 1> A toner containing a binder resin, with a true density of 1.30 g / cm³. 3 More than 1.80g / cm 3 The following conditions apply: the average circularity is less than 0.93, the volume-average particle size is 10 μm or more and 30 μm or less, the loose apparent bulk density is less than 0.55, and the binder resin contains polyurethane resin. The toner has a polyurethane resin content of 51% by mass or more relative to the toner. <Aspect 2> The toner according to embodiment 1, wherein the average roundness is less than 0.90 and the loose apparent bulk density is less than 0.50. <Aspect 3> The toner according to embodiment 1 or 2, wherein the softening temperature is less than 40°C. <Aspect 4> The polyurethane resin has structural units derived from at least an aliphatic diol, The toner according to any one of embodiments 1 to 3, wherein the glass transition temperature of the polyurethane resin is 0°C or lower. <Aspect 5> The polyurethane resin has structural units derived from at least 1,4-butanediol, adipic acid, and diphenylmethane diisocyanate. The toner according to any one of embodiments 1 to 4, wherein the weight-average molecular weight of the polyurethane resin is 40,000 or more and 130,000 or less. <Aspect 6> This toner set comprises a color toner containing a binder resin and a coloring agent, and a toner according to any one of embodiments 1 to 5. <Aspect 7> Support for peeling, This is an image transfer sheet having an image formed by toner according to any one of embodiments 1 to 5 on the aforementioned peelable support. <Aspect 8> The peeling support is an image transfer sheet according to embodiment 7, having a layer formed on its surface consisting of at least a silicone component or a fluorine component. <Pattern 9> This is a toner storage unit for storing toner as described in any one of embodiments 1 to 5. <Aspect 10> Electrostatic latent image carrier, An electrostatic latent image forming unit for forming an electrostatic latent image on the electrostatic latent image carrier, A developing unit that develops the electrostatic latent image formed on the electrostatic latent image carrier with a developer containing toner according to any one of embodiments 1 to 5 to form a toner image, A transfer unit that transfers the toner image formed on the electrostatic latent image carrier onto a peeling support or a flexible recording medium with a surface roughness of 1 μm or more, The image forming apparatus includes a fixing unit for fixing the toner image transferred onto the peeling support or the flexible recording medium. <Aspect 11> An electrostatic latent image formation process for forming an electrostatic latent image on an electrostatic latent image carrier, A developing step in which the electrostatic latent image formed on the electrostatic latent image carrier is developed with a developer containing toner according to any one of embodiments 1 to 5 to form a toner image, A transfer step of transferring the toner image formed on the electrostatic latent image carrier onto a peeling support or a flexible recording medium having a surface roughness of 1 μm or more, The image forming method comprises a fixing step of fixing the toner image transferred onto the peeling support or the flexible recording medium. <Aspect 12> This is an image forming method according to embodiment 11, wherein the toner image is formed on the side closest to the peeling support or the flexible recording medium. <Aspect 13> The image forming method according to embodiment 11 or 12, wherein the flexible recording medium is a cloth made of fibers. <Aspect 14> The image forming method according to any one of embodiments 11 to 13, wherein the thickness of the toner image is 50 μm or more and 150 μm.

[0233] As described above, the embodiments have been explained. However, the above embodiments are presented as examples, and the present invention is not limited by the above embodiments. The above embodiments can be implemented in various other forms, and various combinations, omissions, replacements, changes, etc. can be made without departing from the gist of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalent scope thereof.

Explanation of Signs

[0234] 1 Paper Feed Cassette 2 Paper Feed Roller 3, 4 Registration Roller 4Y, 4C, 4M, 4K, 4A Photoconductor Drum 4' Photoconductor Drum 5, 11, 17, 23, 29 Photoconductor 6, 12, 18, 24, 30 Charger 8, 14, 20, 26, 32 Developing Unit 10, 16, 22, 28, 34 Transferrer 9, 15, 21, 27, 33 Cleaning Device 7, 13, 19, 25, 31 Exposure Light 20Y, 20C, 20M, 20K, 20A Toner Image Forming Unit 20' Toner Image Forming Unit 30' Cleaning Device 40' Charging Device 35 Toner Developing Unit 36 Black Toner Developing Unit 37 Cyan Toner Developing Unit 38 Magenta Toner Developing Unit 39 Yellow Toner Developing Unit 30 Charger 40 Intermediate Transfer Belt 41 Transfer Device 43 Fixing Device 50 Developing Device 60 Intermediate Transfer Belt 61Y, 61C, 61M, 61K, 61A Primary Transfer Roller 65 Secondary Transfer Apparatus 70 Paper feed section 71 Paper feed cassette 72 Paper feed roller 73 Resistola 90 Fixing device 100 domains (island area) [Prior art documents] [Patent Documents]

[0235] [Patent Document 1] Patent No. 5510517 [Patent Document 2] Japanese Patent Publication No. 2012-008172

Claims

1. A toner containing a binder resin, with a true density of 1.30 g / cm³. ３ 1.80g / cm or more ３ The following conditions apply: the average circularity is less than 0.93, the volume-average particle size is 10 μm or more and 30 μm or less, the loose apparent bulk density is less than 0.55, and the binder resin contains polyurethane resin. The toner has a polyurethane resin content of 51% by mass or more relative to the toner.

2. The toner according to claim 1, wherein the average circularity is less than 0.90 and the loose apparent bulk density is less than 0.

50.

3. The toner according to claim 2, wherein the softening temperature is less than 40°C.

4. The polyurethane resin has structural units derived from at least an aliphatic diol, The toner according to claim 3, wherein the glass transition temperature of the polyurethane resin is 0°C or lower.

5. The polyurethane resin has structural units derived from at least 1,4-butanediol, adipic acid, and diphenylmethane diisocyanate. The toner according to claim 4, wherein the weight-average molecular weight of the polyurethane resin is 40,000 or more and 130,000 or less.

6. A toner set comprising a color toner containing a binder resin and a coloring agent, and the toner according to claim 1 or 2.

7. Support for peeling, An image transfer sheet having an image of the toner described in claim 1 or 2 on the peel-off support.

8. The image transfer sheet according to claim 7, wherein the peeling support has a layer formed on its surface consisting of at least a silicone component or a fluorine component.

9. A toner storage unit for storing the toner according to claim 1 or 2.

10. Electrostatic latent image carrier, An electrostatic latent image forming unit for forming an electrostatic latent image on the electrostatic latent image carrier, A developing unit that develops the electrostatic latent image formed on the electrostatic latent image carrier with a developer containing the toner described in claim 1 or 2 to form a toner image, A transfer unit that transfers the toner image formed on the electrostatic latent image carrier onto a peeling support or a flexible recording medium with a surface roughness of 1 μm or more, An image forming apparatus having a fixing unit for fixing the toner image transferred onto the peeling support or the flexible recording medium.

11. An electrostatic latent image formation process for 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 described in claim 1 or 2 to form a toner image, A transfer step of transferring the toner image formed on the electrostatic latent image carrier onto a peeling support or a flexible recording medium with a surface roughness of 1 μm or more, An image forming method comprising a fixing step of fixing the toner image transferred onto the peeling support or the flexible recording medium.

12. The image forming method according to claim 11, wherein the toner image is formed on the side closest to the peeling support or the flexible recording medium.

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

14. The image forming method according to claim 13, wherein the thickness of the toner image is 50 μm or more and 150 μm or less.

Images