Toner, method for manufacturing toner, and two-component developer

Abstract

To provide a toner capable of suppressing further environmental dependency on chargeability of the toner, improving temporal stability, suppressing transfer omission, and suppressing member contamination caused by an external additive and silicone oil.SOLUTION: A toner has toner particles and silica fine particles A on the surfaces of the toner particles. The weight average particle diameter of the toner is in a specific range, the silica fine particles A contain silicone oil, and a carbon reduction rate when the silica fine particles A are cleaned with hexane is 5 to 70%, and areas of respective peaks obtained in CP / MAS measurement of solid 29Si-NMR of the silica fine particles A and the silica fine particles A after being cleaned with hexane are in a specific range.SELECTED DRAWING: None

Description

Technical Field

[0001] The present disclosure relates to a toner and a two-component developer for developing an electrostatic charge image used in an electrophotographic method, an electrostatic recording method, etc., and a method for producing the toner.

Background Art

[0002] In recent years, full-color copiers using the electrophotographic method have become widely popular and have started to be applied to the printing market. In the printing market, high productivity by high-speed, high-image quality, and continuous operation for a long time is required while corresponding to a wide range of media (paper types).

[0003] In order to improve the image quality, it is necessary to stabilize the charging characteristics of the toner. In order to stabilize the charging characteristics of the toner, various studies on external additives have been conducted. For example, in Patent Document 1, a toner having improved charging characteristics by externally adding silica particles surface-treated with cyclic siloxane is disclosed. Patent Document 2 discloses a toner having cyclic siloxane on its surface. In addition, for further improvement in image quality, a toner with high transfer efficiency without dropout during transfer and no image defects is required. For example, in Patent Document 3, a toner having high transfer efficiency by externally adding inorganic fine powder surface-treated with silicone oil is disclosed. Furthermore, in order to achieve high productivity by continuous operation for a long time, studies have been conducted to suppress member contamination by external additives. Patent Document 4 discloses a toner obtained by externally adding silica particles surface-treated with a silane coupling agent and then surface-treated with silicone oil.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Patent Document 3

[0005] However, in order to satisfy the demands for even higher levels of speed, high image quality, and high productivity through long continuous operation, the toner's charge properties must not only be less dependent on the environment but also have high stability over time. Hereafter, such characteristics will also be referred to as charge retention.

[0006] On the other hand, transfer defects, image loss, and contamination of components due to the adhesion of external additives could be suppressed by the release effect achieved by treating with silicone oil, etc. However, for example, charged components require high discharge energy to obtain the desired properties as the transfer speed increases further. When silica nanoparticles are present on the photoreceptor, they receive high discharge energy. In this case, the silicone oil, having received excess energy, may volatilize, detach from the external additive, and adhere to the charged component, contaminating it. This type of component contamination, which occurs when the toner and component are not in contact, cannot be prevented by the release effect of silicone oil as in conventional methods. As a result, uneven charging of the photoreceptor can reduce image uniformity, and further improvements were needed.

[0007] The toner disclosed in the above document suppresses environmental dependence regarding the chargeability of the toner and It was insufficient to simultaneously satisfy the requirements for improving stability over time, as well as suppressing transfer defects and component contamination.

[0008] This disclosure provides a toner that can further suppress environmental dependence regarding the electrostatic properties of the toner, improve stability over time, suppress transfer omissions, and suppress contamination of components by external additives and compounds having a siloxane structure. [Means for solving the problem]

[0009] This disclosure relates to a toner having toner particles and silica fine particles A on the surface of the toner particles, The weight-average particle size of the toner is 4.0 to 15.0 μm. The silica microparticles A contain silicone oil, and the carbon reduction rate when the silica microparticles A are washed with hexane is 5-70%. Solid silica fine particles A 29 In CP / MAS measurements of Si-NMR, the Si in the structure represented by the following formula (1) a Peak PD1 corresponds to the silicon atom shown, and Si in the structure represented by the following formula (2). b A peak PD2 corresponding to the silicon atom shown is observed, and the area of ​​peak PD1 is taken as SD1, and the area of ​​peak PD2 is taken as SD2. Solid silica particles after washing with hexane 29 In CP / MAS measurements of Si-NMR, the Si in the structure represented by the following formula (1) a The peak PD1w corresponding to the silicon atom shown and the Si in the structure represented by the following formula (2) b When peak PD2w, which corresponds to the silicon atom shown, is observed, and the area of ​​peak PD1w is taken as SD1w, and the area of ​​peak PD2w is taken as SD2w, SD2 / SD1 is between 0.05 and 0.30. This applies to toner cartridges where the SD2w / SD1w value is 0.05 or higher.

[0010] [ka] [ka] (In formulas (1) and (2), R independently represents a hydrogen atom, a methyl group, or an ethyl group.) [Effects of the Invention]

[0011] According to the present disclosure, it is possible to provide a toner that can suppress further environmental dependence of the chargeability of the toner, improve the stability over time, suppress dropout during transfer, and suppress member contamination by an external additive and a compound having a siloxane structure.

Mode for Carrying Out the Invention

[0012] In the present disclosure, the description of "XX or more and YY or less" or "XX to YY" indicating a numerical range means a numerical range including the lower limit and the upper limit that are the endpoints, unless otherwise specified. When numerical ranges are described stepwise, the upper and lower limits of each numerical range can be arbitrarily combined. Also, a monomer unit refers to the reacted form of a monomer substance in a polymer.

[0013] The present inventors earnestly studied for the purpose of obtaining a toner that can suppress further environmental dependence, improve the stability over time, suppress dropout during transfer, and suppress member contamination by an external additive and a compound having a siloxane structure. As a result, they found that the following toner can solve the above problems.

[0014] The present disclosure is a toner having toner particles and silica fine particles A on the surface of the toner particles, where the weight average particle diameter of the toner is 4.0 to 15.0 μm, the silica fine particles A contain silicone oil, and the carbon reduction rate when the silica fine particles A are washed with hexane is 5 to 70%, the solid of the silica fine particles A 29 In the CP / MAS measurement of Si-NMR of the solid of the silica fine particles A, Si in the structure represented by the following formula (1) a a peak PD1 corresponding to the silicon atom represented by and Si in the structure represented by the following formula (2) b a peak PD2 corresponding to the silicon atom represented by are observed. Let the area of the peak PD1 be SD1 and the area of the peak PD2 be SD2. the solid of the silica fine particles after washing with hexane 29 In the CP / MAS measurement of Si-NMR of the solid of the silica fine particles A, Si in the structure represented by the following formula (1) aThe peak PD1w corresponding to the silicon atom shown, and the Si in the structure represented by the following formula (2) b When peak PD2w, which corresponds to the silicon atom shown, is observed, and the area of ​​peak PD1w is taken as SD1w, and the area of ​​peak PD2w is taken as SD2w, SD2 / SD1 is between 0.05 and 0.30. This applies to toner cartridges where the SD2w / SD1w value is 0.05 or higher.

[0015] [ka] [ka] (In formulas (1) and (2), R independently represents a hydrogen atom, a methyl group, or an ethyl group.)

[0016] We believe the reasons for the above effects are as follows: Generally, solid 29 In Si-NMR CP / MAS measurements, a peak corresponding to the measured unit structure is observed when the molecular mobility of that unit structure decreases to a certain extent, and the lower the molecular mobility, the larger the peak becomes. Therefore, if silica nanoparticle A is a solid silica nanoparticle A 29 In CP / MAS measurements using Si-NMR, the Si in the structure represented by the above formula (1) a Peak PD1, which corresponds to the silicon atom shown, and Si in the structure represented by formula (2) above. b The presence of a peak PD2 corresponding to the silicon atom shown indicates that the structure shown in formula (1) (D1 unit structure) and the structure shown in formula (2) (D2 unit structure) are reacting with and adhering to the surface of the silica nanoparticle substrate, either via or without the siloxane structure. It is also possible that the D1 unit structure and the D2 unit structure are physically firmly adhering to the surface of the silica nanoparticle substrate. Note that "Si in the structure represented by formula (1)" aThe silicon atom shown is what is known as a silicon atom having a D1 unit structure, and the structure represented by formula (2) is Si b The silicon atom shown is a silicon atom that has a so-called D2 unit structure.

[0017] solid 29 Si-NMR CP / MAS measurements allow us to observe the molecular mobility of the measured unit structure. Specifically, a large peak area corresponding to the measured unit structure indicates low molecular mobility, while a small peak area indicates high molecular mobility. (Silica nanoparticle A - solid) 29 In Si-NMR CP / MAS measurements, the presence of peak PD1 corresponding to the D1 unit structure and peak PD2 corresponding to the D2 unit structure, and the fact that the ratio of the areas of these peaks (SD2 / SD1) falls within a certain range, indicates that the molecular mobility of the D1 and D2 unit structures is controlled. The D1 unit structure of silica nanoparticles A originates mainly from the molecular structure generated by the reaction between the silica nanoparticle substrate and the surface treatment agent. Even when silica nanoparticles A are washed with hexane, the D1 unit structure remains firmly attached to the surface of the silica nanoparticles A and does not detach. Therefore, its molecular mobility is low, and it is a solid. 29 The peak area obtained by CP / MAS measurement using Si-NMR tends to be large.

[0018] On the other hand, the D2 unit structure of silica nanoparticle A mainly originates from the molecular structure of silicone oil that adheres to the surface of the silica nanoparticle substrate with a strength such that it detaches from the surface of silica nanoparticle A when washed with hexane. Therefore, it has high molecular mobility and is solid. 29 The peak area obtained by CP / MAS measurement in Si-NMR tends to be small. If the molecular mobility derived from this D2 unit structure is too high, external stimuli such as discharge energy can easily cause silicone oil to be released or volatilized from the surface of silica nanoparticles A, leading to contamination of charged components and other materials.

[0019] Silica nanoparticles A have D1 and D2 unit structures on their surface. The D2 unit structure is structurally similar to silicone oil and has high affinity for it. The D1 unit structure has polar -OR groups at its molecular ends. Therefore, in relation to the polarity of the silica nanoparticle substrate surface, the molecular motion of the D2 unit structure between the surface of the silica nanoparticle substrate and the -OR groups can be suppressed. As a result, the molecular motion of the silicone oil contained in silica nanoparticles A is controlled to a low level, and even when subjected to external stimuli such as discharge energy, the silicone oil is less likely to be released or volatilized from the surface of silica nanoparticles A, thus reducing contamination of charged components. Such effects are observed in the solid form of silica nanoparticles A. 29 In Si-NMR CP / MAS measurements, it was found that the best performance was observed when the SD2 / SD1 ratio was between 0.05 and 0.30. Specifically, the SD2 / SD1 ratio is between 0.05 and 0.30. Having the SD2 / SD1 ratio within this range provides sufficient protection against transfer defects and image loss caused by silicone oil, and also results in a toner that is less prone to contamination of charged components. The SD2 / SD1 ratio is preferably between 0.10 and 0.28, and more preferably between 0.12 and 0.27.

[0020] When measuring the physical properties of silica fine particles A, if it is necessary to separate the silica fine particles A from the toner particles, the measurements can be taken after separation using the method described below. In this method, separation is performed in an aqueous medium, so no elution of silicon compounds into the medium occurs. As a result, silica microparticles A can be separated from toner particles while maintaining the physical properties of silica microparticles A before the separation process. Therefore, the values ​​of each physical property measured using silica microparticles A separated from toner particles are substantially the same as the values ​​of each physical property measured using silica microparticles A before external addition.

[0021] <Solid 29 Si-NMR measurement method > solid 29The specific measurement conditions for Si-NMR are as follows: Equipment: JNM-ECA400 (JEOL RESONANCE) Calibration: TMS (tetramethylsilane) to 0 ppm Temperature: room temperature Measurement method: CP / MAS method 29 Si 45° Sample tube: Zirconia 8.0 mmφ Sample: A test tube is filled with silica microparticles A in powder form. Sample rotation speed: 6kHz Relaxation delay: 90 seconds Scan: 5640 In the NMR spectrum obtained by the above-described measurement, the peak originating from the siloxane chain appearing around -20 ppm is separated to obtain peak PD1 corresponding to silicon atoms with a D1 unit structure and peak PD2 corresponding to silicon atoms with a D2 unit structure. From these peaks, the peak areas SD1 and SD2 are determined. Peak separation is performed using the following procedure.

[0022] (Peak separation method) Peak separation is performed by analyzing the NMR spectrum data obtained using the method described above. Peak separation can be performed using commercially available software or a program created in-house, following the procedure described below. The peak positions are fixed at -18.2 ppm for peak PD1 and -21.0 ppm for peak PD2, and peak separation is performed using the Voigt function.

[0023] (Method for separating silica microparticles A from toner particles) Weigh 20g of a 10% aqueous solution of "Contaminon N" (a pH 7 neutral detergent for cleaning precision measuring instruments consisting of a nonionic surfactant, anionic surfactant, and organic builder) into a 50mL vial and mix with 1g of toner. The mixture is placed in an Iwaki Sangyo Co., Ltd. "KM Shaker" (model: V.SX), and the speed is set to 50 and shaken for 30 seconds. This causes the silica microparticles A to migrate from the surface of the toner particles to the aqueous solution. Subsequently, in the case of magnetic toner containing magnetic material, the toner particles are restrained using a neodymium magnet, and the silica microparticles that have migrated to the supernatant liquid are separated. The settled toner is then dried under vacuum (40°C / 24 hours) to obtain silica microparticles. In the case of non-magnetic toner, a centrifuge (H-9R; manufactured by Kokusan Co., Ltd.) (5 minutes at 1000 rpm) is used to separate the toner particles from the silica microparticles that have migrated to the supernatant liquid. Furthermore, if external additives other than silica microparticle A are added to the toner, the silica microparticle A and the other external additives can be separated by centrifugal separation of the external additives separated from the toner using the method described above. Even if multiple types of silica microparticles are added to the toner, separation is possible by centrifugal separation as long as they have different particle size ranges. For example, separation can be performed using a CS120FNX (manufactured by Hitachi Koki Co., Ltd.) at 40,000 rpm for 20 minutes.

[0024] The carbon reduction rate (hereinafter also simply referred to as the carbon reduction rate) when silica nanoparticles A are washed with hexane is 5-70%. The decrease in carbon content when washed with hexane indicates that silica nanoparticles A contain free carbon components. Silicone oil is one example of a free carbon component. Furthermore, the fact that the carbon reduction rate when washed with hexane falls within the above range suggests that the surface of the siloxane nanoparticle substrate and the D1 and D2 unit structures are firmly bonded, or that they are bonded, either via or without the siloxane structure. By controlling the carbon reduction rate within the above range, a mold release effect similar to that of conventional silica nanoparticles can be obtained. As a result, environmental dependence can be suppressed, stability over time can be improved, transfer voids can be suppressed, and contamination of materials by external additives and silicone oil can be suppressed. Since contamination of the material by free carbon components can be effectively suppressed, the carbon reduction is preferably 10-70%, more preferably 25-65%, and even more preferably 30-55%. The carbon reduction rate can be controlled by a two-stage surface treatment using a surface treatment agent containing siloxane bonds and silicone oil, the amount of silicone oil used, the surface treatment temperature, and the surface treatment time. The carbon reduction rate can be increased by increasing the amount of silicone oil used, decreasing the surface treatment temperature, and shortening the surface treatment time. On the other hand, the carbon reduction rate can be decreased by decreasing the amount of silicone oil used, increasing the surface treatment temperature, and extending the surface treatment time.

[0025] <Measurement of carbon loss rate when silica microparticles A are washed with hexane> 1.0 g of silica microparticles is weighed into a 50 ml screw-cap tube, and 20 ml of n-hexane is added. Then, the sample is extracted for 10 minutes at an intensity of 20 (output 10 W) using an ultrasonic homogenizer (TAITEC VP-050). The resulting extract is separated using a centrifuge, the supernatant is removed, and the n-hexane is removed from the resulting wet sample using an evaporator to obtain silica microparticles after hexane washing. The carbon content of silica microparticles before and after hexane washing is measured using a total nitrogen / total carbon analyzer (Sumigraph NC-22F, manufactured by Sumika Analysis Center), and the carbon reduction rate (%) is calculated using the following formula. {(Carbon content of silica particles before hexane washing (mass%)) - (Carbon content of silica particles after hexane washing (mass%))} / (Carbon content of silica particles before hexane washing (mass%) × 100)

[0026] After washing silica nanoparticles A with hexane, silica nanoparticles A have a D2 unit structure. The fact that silica nanoparticles A have a D2 unit structure after washing with hexane means that the silica nanoparticles A after washing with hexane are the same as the solids described above. 29 This can be confirmed by analysis using the Si-NMR measurement method. That is, the solid silica fine particles after washing with hexane. 29 In CP / MAS measurements using Si-NMR, the Si in the structure represented by the above formula (1) a The peak PD1w corresponding to the silicon atom shown, and the Si in the structure represented by formula (2) above. b The peak PD2w, corresponding to the silicon atom shown, is observed. The fact that silica nanoparticles A have a D2 unit structure after being washed with hexane suggests that a portion of the D2 unit structure is firmly attached to the surface of the silica nanoparticle substrate, or is bonded to it, either via or without the siloxane structure. Furthermore, when the area of ​​peak PD1w is denoted as SD1w and the area of ​​peak PD2w is denoted as SD2w, the ratio of SD2w / SD1w is 0.05 or greater. Within this range, it can be confirmed that silica fine particles A have a D2 unit structure even after hexane washing. The ratio of SD2w / SD1w is preferably 0.05 to 0.34, and more preferably 0.13 to 0.32. It is more preferable that the value be between 0.17 and 0.30. The D2 unit structure is fixed to the surface of the silica nanoparticle substrate in the manner described above, making it easier to satisfy the carbon reduction rate mentioned above. The manner in which the D2 unit structure is fixed as described above can be adjusted by a two-step surface treatment using a surface treatment agent containing siloxane bonds and silicone oil, as well as by the surface treatment temperature and surface treatment time.

[0027] Furthermore, it is preferable that the components released when silica fine particles A are washed with hexane contain silicone oil. The silicone oil has a D2 unit structure. The fact that the components released when silica nanoparticles A were washed with hexane included silicone oil having a D2 unit structure suggests that there is a weakly adhering layer of silicone oil on the surface of the silica nanoparticle substrate. The fact that the components released when silica nanoparticles A are washed with hexane have a D2 unit structure can be confirmed by separating the extract from the hexane solution and performing a compositional analysis.

[0028] <Analysis method for components released when silica microparticles A are washed with hexane> Specifically, 0.5 g of silica microparticles B and 32 ml of n-hexane are placed in a 50 ml centrifuge tube, and ultrasonically dispersed for 30 minutes using an ultrasonic cleaner (Yamato Scientific 1510JMTH) to suspend the sample. The resulting suspension is then centrifuged to separate and recover the liquid phase (silicone oil). The separated and recovered material is confirmed to be silicone oil by obtaining and comparing the infrared absorption spectra of the separated and recovered material with those of a silicone oil prepared as a standard sample.

[0029] The amount of free components based on carbon in silica fine particles A is preferably 1.0 to 20.0 parts by mass, more preferably 3.0 to 9.0 parts by mass, even more preferably 5.0 to 8.0 parts by mass, and particularly preferably 6.0 to 8.0 parts by mass per 100 parts by mass of silica fine particles A. By setting the amount of free components within the above range, contamination of materials by free carbon components can be further suppressed, and transfer defects can be reduced. This also leads to reduced environmental dependence of toner charge properties and improved stability over time. The amount of free components relative to carbon in silica nanoparticles A can be increased by increasing the amount of silicone oil treated, lowering the surface treatment temperature, and shortening the surface treatment time. Conversely, the amount of free components relative to carbon in silica nanoparticles A can be decreased by reducing the amount of silicone oil treated, raising the surface treatment temperature, and extending the surface treatment time.

[0030] <Method for measuring the amount of free components based on carbon in silica microparticles A> The amount of free components based on carbon in silica nanoparticles A can be determined by measuring the amount of silicone oil that dissolves when the nanoparticles are immersed in n-hexane. Specifically, 0.5 g of silica microparticles A and 32 ml of n-hexane are placed in a 50 ml centrifuge tube, and ultrasonically dispersed for 30 minutes using an ultrasonic cleaner (Yamato Scientific 1510JMTH) to suspend the particles. The resulting suspension is centrifuged to separate and recover the solid phase (silica). Another 32 ml of n-hexane is added to the recovered silica, and the ultrasonic dispersion and centrifugation operations are repeated a total of three times. Finally, the mixture is dried under reduced pressure (120°C, 12 hours) to obtain a dried powder. The carbon content of this powder is measured using a total nitrogen / total carbon analyzer (Sumigraph NC-22F, manufactured by Sumika Analysis Center). The total carbon content of 0.5 g of the sample is measured beforehand, and the amount of extracted free components is calculated from the difference between this total carbon content and the measured amount.

[0031] From the viewpoint of environmental dependence and long-term stability, silica nanoparticles A have a BET specific surface area of ​​30 to 170 m². 2 / g is preferred, 40-160m 2 / g is more preferable, 60-160m 2 / g is more preferable, 70-160 m 2 It is particularly preferable that the amount be 74-155m 2 It is especially preferable that it be / g. Because the BET specific surface area of ​​silica nanoparticles A is within the aforementioned range, silica nanoparticles A can properly coat toner particles, allowing them to exhibit their full potential. As a result, even when high discharge energy is applied during the charging process, compounds with a siloxane structure present on the surface of silica nanoparticles A remain more easily, becoming less susceptible to peeling due to the discharge energy, and further suppressing contamination of the material. Furthermore, the charge state on the toner surface is kept more constant, and the charged state becomes more stable, further improving charge retention. In addition, compounds with a siloxane structure are appropriately free on the surface of silica fine particles A, improving the release properties of the toner. As a result, even when aiming for higher image quality and higher speed, transfer dropouts can be further suppressed. The BET specific surface area of ​​silica nanoparticle A can be adjusted by the BET specific surface area of ​​the silica nanoparticle substrate used, the amount of silicone oil, and other factors.

[0032] <Measurement of BET specific surface area of ​​silica particles> The BET specific surface area of ​​silica nanoparticles can be determined by the BET method (BET multi-point method) using a low-temperature gas adsorption method with a dynamic constant-pressure approach. By using a specific surface area measuring device (product name: Gemini 2375 Ver. 5.0, manufactured by Shimadzu Corporation), nitrogen gas is adsorbed onto the sample surface, and the BET specific surface area (m²) is measured using the BET multi-point method. 2 It is possible to calculate ( / g).

[0033] BET specific surface area of ​​silica nanoparticle A at a temperature of 30°C and relative humidity of 80% 2 The amount of water adsorbed per unit area is 0.01 to 0.07 cm, considering environmental dependence. 3 / m 2 Preferably, 0.01 to 0.05 cm 3 / m 2 More preferably, 0.02-0.03 cm 3 / m 2 That is even more preferable. The amount of moisture adsorbed by silica nanoparticles A is influenced by the surface condition of silica nanoparticles A. When the amount of moisture adsorbed by silica nanoparticles A falls within the aforementioned range, it indicates that the surface of silica nanoparticles A is covered with modifying groups having appropriate polarity. Therefore, compounds having a siloxane structure can be more firmly retained on the surface of silica nanoparticles A. As a result, even when high discharge energy is applied during the charging process, compounds having a siloxane structure on the surface of silica nanoparticles A are more likely to remain, becoming less susceptible to peeling due to the discharge energy, and further suppressing contamination of the material. Furthermore, the charge state on the toner surface is kept more constant, and the charged state becomes more stable, further improving charge retention. In addition, compounds with a siloxane structure are appropriately free on the surface of silica fine particles A, improving the release properties of the toner. As a result, even when aiming for higher image quality and higher speed, transfer dropouts can be further suppressed. The amount of moisture adsorbed by silica nanoparticles A can be increased by lowering the surface treatment temperature and shortening the surface treatment time. Conversely, the amount of moisture adsorbed by silica nanoparticles A can be decreased by increasing the surface treatment temperature and extending the surface treatment time.

[0034] <Method for measuring water adsorption amount> The amount of moisture adsorbed by silica nanoparticles A is measured using an adsorption equilibrium measuring device (BELSORP-aqua3: manufactured by Nippon Bell Co., Ltd.). This device measures the amount of adsorbed gas (water vapor) of the target gas.

[0035] (Degassing) Degas any moisture adsorbed on the sample before measurement. Attach the cell, filler rod, and cap, and weigh the empty cell. Weigh 0.3g of sample and place it into the cell. Insert the filler rod into the cell, attach the cap, and connect it to the degassing port. Once all cells to be measured are connected to the degassing ports, open the helium valve. Turn on the button for the degassing port, and... Press the "VAC" button. This will allow the system to degas for at least one day.

[0036] (measurement) Turn on the power to the main unit (there is a switch on the back of the unit). Start the vacuum pump at the same time. Turn on the power to the main unit and control panel for circulating water. Launch "BELaqua3.exe" (measurement software) located in the center of the PC screen. Temperature control of the high-temperature air chamber: Double-click "SV" in the "TIC1" frame on the "Flow Diagram" window to open the "Temperature Setting" window. Enter the temperature (80℃) and click Set. Controlling the adsorption temperature: Double-click "SV" under "Adsorption Temperature" in the "Flow Diagram" window and enter the "SV value" (adsorption temperature). Click "Start Circulation" and "Outside Temperature Control," then click "Settings." Press the "PURGE" button to stop degassing, turn off the port button, remove the sample, attach cap 2, weigh the sample, and then attach the sample to the main unit's measuring section. On the PC, click "Measurement Conditions" to open the "Measurement Conditions Settings" window. The measurement conditions are as follows:

[0037] Air bath temperature: 80.0°C, Adsorption temperature: 30.0°C, Adsorbate name: H2O, Equilibrium time: 500 sec, Temperature waiting time: 60 min, Saturated vapor pressure: 4.245 kPa, Sample tube pumping speed: Normal, Chemistry: Not measured, Initial introduction volume: 0.20 cm 3 (STP)·g -1 Number of relative pressure measurement ranges: 4 Select the number of samples to measure, enter the "Measurement Data File Name" and "Sample Weight," and then start the measurement. (analysis) Launch the analysis software and perform the analysis to determine the amount of water adsorbed per unit mass at a relative water vapor pressure of 80% (cm³). 3 The amount of water adsorbed per unit mass is calculated by dividing the calculated amount of water adsorbed per unit mass by the BET specific surface area of ​​the silica nanoparticles obtained by the method described above. 3 / m 2 )

[0038] As the silica nanoparticle substrate, which is the silica nanoparticle before surface treatment, known materials can be used. Examples include silicon compounds, particularly silicon halides, generally silicon chlorides, fumed silica usually produced by burning purified silicon tetrachloride in an oxyhydrogen flame, wet silica produced from water glass, sol-gel silica particles obtained by a wet process, gel silica particles, aqueous colloidal silica particles, alcoholic silica particles, molten silica particles obtained by a gas-phase process, and deflagration silica particles. Fumed silica is preferred.

[0039] It is preferable that silica nanoparticles A have a compound having a siloxane structure on their surface. It is preferable that silica nanoparticles A are obtained by mixing a silica nanoparticle substrate with a surface treatment agent containing siloxane bonds, performing a heat treatment (first stage treatment), and then treating with silicone oil (second stage treatment). When treated with silicone oil, since silica nanoparticles A have a compound having a siloxane structure on their surface, the silicone oil and the compound having a siloxane structure partially chemically react and adhere to the surface. On the other hand, the silicone oil that did not react exists as a free component on the surface of silica nanoparticles A. Silica nanoparticles A adhere to the surface of silica nanoparticles A through a partial chemical reaction between the silicone oil and a compound having a siloxane structure. As a result, the silicone oil present as a free component on the surface of silica nanoparticles A has a high affinity for it. Therefore, the state of the silicone oil present as a free component can be stabilized. Consequently, volatilization can be suppressed even when subjected to higher energy than before, and it is believed that contamination of materials originating from silicone oil can be suppressed. In this disclosure, when silica nanoparticles A are surface-treated with a surface treatment agent such as silicone oil, the portion derived from the surface treatment agent is also referred to as silica nanoparticles A. The particles are sometimes referred to as "silica microparticle substrates."

[0040] A method for manufacturing toner preferably includes the steps of obtaining silica fine particles A and mixing the silica fine particles A with toner particles to obtain toner. Furthermore, a method for manufacturing toner preferably includes the step of preparing the silica fine particles A obtained in the following steps. The step of obtaining silica fine particles A is preferably: A step of mixing a silica nanoparticle substrate with a surface treatment agent containing siloxane bonds (preferably a cyclic siloxane), and performing a heat treatment at a temperature of 295°C (preferably 300°C) or higher to obtain a surface-treated product of the silica nanoparticle substrate with the surface treatment agent containing siloxane bonds, and The process includes a step of further surface-treating the surface-treated material with silicone oil to obtain silica fine particles A.

[0041] In addition to obtaining silica nanoparticles A by treating the surface of a silica nanoparticle substrate with a surface treatment agent containing siloxane bonds and silicone oil, the surface of a silica nanoparticle substrate may also be obtained by treating it with other surface treatment agents containing siloxane bonds. The surface treatment agent containing siloxane bonds is not particularly limited, and known materials can be used. To easily obtain the above physical properties, it is preferable to perform a surface treatment on the silica fine particle substrate.

[0042] Surface treatment agents containing siloxane bonds include, for example, silicone oils such as dimethyl silicone oil; silicone oils in which the side chains or terminals of dimethyl silicone oil are modified with organic groups, such as methyl hydrogen silicone oil, methylphenyl silicone oil, alkyl-modified silicone oil, chloroalkyl-modified silicone oil, chlorophenyl-modified silicone oil, fatty acid-modified silicone oil, polyether-modified silicone oil, alkoxy-modified silicone oil, carbinol-modified silicone oil, amino-modified silicone oil, and fluorine-modified silicone oil; and cyclic siloxanes such as hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, and decamethylcyclopentasiloxane. The surface treatment agent containing siloxane bonds is preferably a cyclic siloxane. More preferably, it is a cyclic siloxane with up to 10 membered rings. The cyclic siloxane may have substituents on some of the methyl groups bonded to the silicon atoms. Silica fine particles A is preferably a silicone oil-treated product of silica fine particles treated with a cyclic siloxane. The cyclic siloxane is preferably at least one selected from the group consisting of hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, and decamethylcyclopentasiloxane. The cyclic siloxane is more preferably octamethylcyclotetrasiloxane.

[0043] The method for surface treatment of the silica microparticle substrate is not particularly limited and can be carried out by contacting the silica microparticle substrate with a surface treatment agent containing siloxane bonds. From the viewpoint of uniformly treating the surface of the silica microparticle substrate and easily achieving the above physical properties, it is preferable to contact the silica microparticle substrate with the surface treatment agent in a dry manner. As will be described later, examples include contacting the silica microparticle substrate with the vapor of the surface treatment agent, or spraying the undiluted solution of the surface treatment agent or a diluted solution with various solvents into contact with the silica microparticle substrate. The processing temperature is not particularly limited, as it varies depending on the reactivity of the surface treatment agent used. It is preferable to mix the silica fine particle substrate and the surface treatment agent and heat-treat them at a temperature of 300°C or higher. More preferably, it is between 300°C and 380°C.

[0044] By heat treatment at a high temperature of 300°C or higher, the units formed by the surface treatment agent containing siloxane bonds that have reacted with the silica surface react with another silica surface, cleaving the molecular structure and reducing the bulk of the molecular structure. As a result, it reacts effectively with the silanol groups on the surface of the silica nanoparticles. It is possible to form a compound having a dense siloxane structure on the surface of silica nanoparticles.

[0045] The processing time varies depending on the processing temperature and the reactivity of the surface treatment agent used, but is preferably 5 minutes to 300 minutes, more preferably 30 minutes to 240 minutes, and even more preferably 60 minutes to 200 minutes. The processing temperature and processing time for surface treatment being within the above range is preferable from the viewpoint of allowing the treatment agent to react sufficiently with the silica fine particle substrate, and from the viewpoint of production efficiency.

[0046] For contact between the surface treatment agent and the silica microparticle substrate, it is preferable to contact the surface treatment agent vapor under reduced pressure or in an inert gas atmosphere such as a nitrogen atmosphere. Using the vapor contact method makes it easier to remove surface treatment agents that do not react with the silica microparticle surface and facilitates control of the amount of moisture adsorbed. When using the vapor contact method, it is preferable to perform the treatment at a treatment temperature above the boiling point of the surface treatment agent. The above contact may be carried out in multiple steps (for example, 2 to 3 times).

[0047] Among cyclic siloxanes, octamethylcyclotetrasiloxane is more preferred from the viewpoint of ease of chain length control and ease of purification. By using octamethylcyclotetrasiloxane, the chain length can be controlled more uniformly, and the surface of silica nanoparticles A can be more appropriately coated with modifying groups having appropriate polarity. As a result, even when high discharge energy is applied during the charging process, the silicone oil present on the surface of silica nanoparticles A becomes even less likely to peel off due to the discharge energy, further suppressing material contamination. In addition, the charge state on the toner surface is kept more constant, and the charged state becomes more stable, further improving the charge retention performance. Furthermore, compounds having a siloxane structure are appropriately free on the surface of silica microparticles A, improving the release properties of the toner. As a result, even when aiming for higher image quality and faster transfer speeds, transfer dropouts can be further suppressed.

[0048] The amount of surface treatment agent is preferably 40 to 150 parts by mass, and more preferably 70 to 140 parts by mass, per 100 parts by mass of silica fine particle substrate. In particular, when surface treatment is performed by contacting with a cyclic siloxane using vapor, it is preferable to add 100 parts by mass or more per 100 parts by mass of silica fine particle substrate. This allows for uniform surface treatment of the silica fine particle substrate, and thus the surface of the silica fine particles can be more appropriately covered with modifying groups having appropriate polarity. As a result, even when high discharge energy is applied during the charging process, the silicone oil present on the surface of silica nanoparticles A tends to remain, becoming even less prone to peeling due to the discharge energy, further suppressing material contamination. In addition, the charge state on the toner surface is kept more constant, and the charged state becomes more stable, further improving charge retention. Furthermore, compounds with a siloxane structure are appropriately free on the surface of silica nanoparticles A, improving the release properties of the toner. As a result, even when aiming for higher image quality and higher speed, transfer dropouts can be further suppressed.

[0049] Furthermore, when performing surface treatment under reduced pressure, it is preferable that the pressure due to the vapor of the surface treatment agent in the container be between 0.1 Pa and 100.0 Pa, and more preferably between 1.0 Pa and 10.0 Pa. By maintaining this pressure range, the frequency of contact between the vapor molecules of the surface treatment agent is reduced, suppressing chemical reactions between the surface treatment agents and allowing the chemical reaction between the surface treatment agent in contact with the surface of the silica microparticle substrate to proceed preferentially. Furthermore, reaction byproducts generated by the chemical reaction between the silica microparticle substrate and the surface treatment agent can be easily removed from the vicinity of the silica microparticle surface, allowing the surface treatment agent to come into closer contact with the surface of the silica microparticle substrate, and enabling more uniform surface treatment of the silica microparticle substrate.

[0050] Furthermore, when performing surface treatment under reduced pressure, it is preferable to perform a degassing treatment by heating the silica microparticle substrate under reduced pressure to remove moisture and other substances adsorbed on the surface of the silica microparticle substrate before bringing the surface treatment agent into contact with the surface of the silica microparticle substrate. This makes it easier for the surface treatment agent to come into contact with the surface of the silica microparticle substrate, allowing for more uniform surface treatment of the silica microparticle substrate. In addition, from the viewpoint of making it easier for the surface treatment agent to come into contact with the surface of the silica microparticle substrate, it is also preferable to repeat the degassing treatment and the surface treatment of the silica microparticles with the surface treatment agent.

[0051] It is preferable to mix a silica microparticle substrate with a surface treatment agent containing siloxane bonds and heat-treat the mixture, and then further treat the silica microparticle substrate with silicone oil. The second reaction, the heat treatment with silicone oil, is preferably performed at a temperature of 300°C or higher. In other words, it is preferable that the temperature when the surface-treated material is further treated with silicone oil is 300°C or higher. By using a processing temperature of 300°C or higher, the surface of the silica microparticles treated with cyclic siloxane and the silicone oil become more uniformly compatible, and the interaction between the cyclic siloxane-modified groups on the silica microparticle surface and the silicone oil becomes stronger. As a result, even when high discharge energy is applied during the charging process, the silicone oil present on the surface of silica nanoparticles A tends to remain, becoming even less likely to peel off due to the discharge energy, further suppressing material contamination. In addition, the charge state on the toner surface is kept more constant, and the charged state becomes more stable, further improving charge retention. Furthermore, compounds having a siloxane structure are appropriately free on the surface of silica microparticles A, improving the release properties of the toner. As a result, even when aiming for higher image quality and faster transfer speeds, transfer dropouts can be further suppressed.

[0052] Furthermore, the terminal D1 unit structures generated during the first-stage treatment with a surface treatment agent containing siloxane bonds partially react with silicone oil. By setting the treatment temperature to 300°C or higher, the carbon reduction rate during washing with hexane can be controlled. The treatment time for the silicone oil is preferably 40 minutes to 150 minutes, and more preferably 60 minutes to 120 minutes, in order to uniformly treat the silica surface.

[0053] The carbon content (mass%) of the silica fine particles after the first stage of processing is not particularly limited, but is preferably 0.1% to 5.0% by mass, more preferably 0.5% to 4.5% by mass, and even more preferably 1.0% to 4.0% by mass. The carbon content of silica nanoparticles after the first stage of processing can be measured in the same manner as the measurement of the carbon reduction rate described above.

[0054] The amount of silicone oil added is preferably 3 to 25 parts by mass, and more preferably 5 to 20 parts by mass, per 100 parts by mass of the silica microparticle substrate. By using the above amount, it is possible to uniformly treat the surface of the silica microparticles A while effectively obtaining interaction between the surface treatment agent containing siloxane bonds and the modifying groups on the surface of the silica microparticles A. As a result, even when high discharge energy is applied during the charging process, the silicone oil present on the surface of silica nanoparticles A tends to remain, becoming even less likely to peel off due to the discharge energy, further suppressing material contamination. In addition, the charge state on the toner surface is kept more constant, and the charged state becomes more stable, further improving charge retention. Furthermore, compounds having a siloxane structure are appropriately free on the surface of silica microparticles A, improving the release properties of the toner. As a result, even when aiming for higher image quality and faster transfer speeds, transfer dropouts can be further suppressed.

[0055] The kinematic viscosity of silicone oil at a temperature of 25°C is 30-500 mm, which is necessary for controlling the molecular mobility derived from the silicone oil. 2 / s is preferred, and 40-200mm 2 / s is good Preferably 70-130mm 2 A value of / s is even more preferable. By controlling the kinematic viscosity of the silicone oil at a temperature of 25°C to the above range, the chain length of the silicone oil becomes within an appropriate range, and effective interaction with the cyclic siloxane modifying groups on the surface of the silica fine particles can be obtained. As a result, even when high discharge energy is applied during the charging process, the silicone oil present on the surface of silica nanoparticles A tends to remain, becoming even less likely to peel off due to the discharge energy, further suppressing material contamination. In addition, the charge state on the toner surface is kept more constant, and the charged state becomes more stable, further improving charge retention. Furthermore, compounds having a siloxane structure are appropriately free on the surface of silica microparticles A, improving the release properties of the toner. As a result, even when aiming for higher image quality and faster transfer speeds, transfer dropouts can be further suppressed.

[0056] The carbon content (mass%) of the silica fine particles after the second-stage treatment with silicone oil is not particularly limited, but is preferably 0.2 mass% to 10.0 mass%, more preferably 1.0 to 8.4 mass%, and even more preferably 2.0 to 7.0 mass%. The carbon content of silica nanoparticles after the second stage of processing can be measured in the same manner as the measurement of the carbon reduction rate described above.

[0057] The silica nanoparticles A obtained by the surface treatment method described above can be used in combination with silica nanoparticles B obtained by treating the surface of a silica nanoparticle substrate with a surface treatment agent containing siloxane bonds to obtain even more favorable effects. In other words, it is preferable that the toner further contains silica nanoparticles B that are different from silica nanoparticles A.

[0058] It is believed that the siloxane-structured compound, such as silicone oil, present on the surface of silica nanoparticle A interacts with the appropriately polarized modifying groups on the surface of silica nanoparticle B. Therefore, even when high discharge energy is applied during the charging process, the siloxane-structured compound, such as silicone oil, is less likely to peel off from silica nanoparticles A and B due to the discharge energy, further suppressing contamination of the components. Furthermore, the charge state on the toner surface is kept more constant, and the charged state becomes more stable, further improving charge retention. In addition, compounds having a siloxane structure are appropriately free on the surface of silica fine particles A and B, improving the release properties of the toner. As a result, even when aiming for higher image quality and higher speed, transfer dropouts can be further suppressed.

[0059] The toner manufacturing method preferably includes a step of obtaining silica fine particles B. Furthermore, the toner manufacturing method preferably includes a step of preparing the silica fine particles B obtained in the following steps. The step of obtaining silica fine particles B is preferably: The process includes the steps of: mixing a silica microparticle substrate with a surface treatment agent containing siloxane bonds; performing a heat treatment at a temperature of 295°C (preferably 300°C) or higher to surface-treat the surface of the silica microparticle substrate with the surface treatment agent containing siloxane bonds to obtain silica microparticles B.

[0060] In other words, it is preferable that the silica nanoparticles B are treated with a surface treatment agent containing siloxane bonds. The method of surface treatment of silica nanoparticles B with a surface treatment agent containing siloxane bonds is the same as the method described above for silica nanoparticles A. When surface treating silica nanoparticles B, it is preferable to carry out the contact with the vapor of the surface treatment agent containing siloxane bonds in multiple steps (for example, 2 to 4 times). It is preferable that the silica nanoparticles B are surface treated with a cyclic siloxane.

[0061] Silica nanoparticles B are, for example, fumes produced by burning silicon compounds, particularly silicon halides, generally silicon chlorides, usually purified silicon tetrachloride, in an oxyhydrogen flame. Examples include fumed silica, wet silica produced from water glass, sol-gel silica particles obtained by a wet process, gel silica particles, aqueous colloidal silica particles, alcoholic silica particles, fused silica particles obtained by a gas-phase process, and deflagration silica particles. Fumed silica is preferred.

[0062] The number-average particle size of silica nanoparticles B is preferably 5 to 500 nm, more preferably 50 to 300 nm, and even more preferably 80 to 200 nm. Furthermore, it is preferable that the number-average particle size of silica nanoparticles B is 50 nm or larger than the number-average particle size of silica nanoparticles A. For example, it is preferable that the number-average particle size of silica nanoparticles B is 50 to 200 nm larger than the number-average particle size of silica nanoparticles A. When the number-average particle sizes of silica nanoparticles A and B are within the range described above, a compound having a siloxane structure, such as silicone oil, present on the surface of silica nanoparticle A can interact with the surface of silica nanoparticle B, allowing silica nanoparticles A to diffuse appropriately without becoming localized on the surface of silica nanoparticle B. As a result, even when high discharge energy is applied during the charging process, compounds with a siloxane structure, such as silicone oil, become less likely to peel off from silica microparticles A and B due to the discharge energy, further suppressing material contamination. In addition, the charge state on the toner surface is kept more constant, and the charged state becomes more stable, further improving charge retention. Furthermore, compounds with a siloxane structure are appropriately free on the surface of silica microparticles A and B, improving the release properties of the toner. As a result, even when aiming for higher image quality and higher speed, transfer dropouts can be further suppressed.

[0063] <Method for measuring the number-average particle size of silica microparticles> Using the Microtrac particle size distribution analyzer HRA(X-100) (manufactured by Nikkiso Co., Ltd.), measurements can be taken with a range setting of 0.001 μm to 10 μm. Furthermore, the toner particles can be observed using a scanning electron microscope (SEM) to measure the number and particle size (maximum diameter) of silica microparticles present on the surface of the toner particles, thereby obtaining a substantially equivalent number-average particle size. In this case, energy-dispersive X-ray spectroscopy (EDS), which is associated with the SEM, can be used to confirm that the measured object is silica microparticles. When using silica microparticles A and B in combination, since the difference in particle size is usually large, the average particle size can be calculated by separating the particles into those larger than a predetermined particle size boundary and those smaller than that boundary. The particle size used as the boundary can be determined by measuring the particle size distribution of silica microparticles on the surface of the toner particles and using the particle size at which the frequency falls in a valley (a minimum value sandwiched between maximum values).

[0064] The toner particles may contain a binder resin. Known binder resins can be used for the toner particles. For example, the following are examples of binder resins: Styrene resins, styrene copolymer resins, polyester resins, polyol resins, polyvinyl chloride resins, phenol resins, naturally modified phenol resins, naturally modified maleic acid resins, acrylic resins, methacrylic resins, polyvinyl acetate, silicone resins, polyurethane resins, polyamide resins, furan resins, epoxy resins, xylene resins, polyvinyl butyral, terpene resins, coumarone indene resins, and petroleum resins. Preferably used resins include styrene copolymer resins, polyester resins, and hybrid resins obtained by mixing polyester resin and styrene copolymer resin or by partial reaction of both. Preferably, polyester resin is used.

[0065] The components that make up polyester resin are described in detail. Note that depending on the type and application, one or more of the following components may be used. Examples of divalent carboxylic acid components that make up polyester resins include the following dicarboxylic acids or their derivatives: phthalic acid, terephthalic acid, isophthalic acid, phthalic anhydride, etc. Benzene dicarboxylic acids or their anhydrides or lower alkyl esters; alkyl dicarboxylic acids such as succinic acid, adipic acid, sebacic acid, and azelaic acid or their anhydrides or lower alkyl esters; alkenyl succinic acids or alkyl succinic acids with an average number of carbon atoms of 1 to 50 or less, or their anhydrides or lower alkyl esters; unsaturated dicarboxylic acids such as fumaric acid, maleic acid, citraconic acid, and itaconic acid or their anhydrides or lower alkyl esters. Examples of alkyl groups in lower alkyl esters include methyl, ethyl, propyl, and isopropyl groups.

[0066] On the other hand, the following are examples of divalent alcohol components that make up polyester resin. Ethylene glycol, polyethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, diethylene glycol, triethylene glycol, 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, 2-methyl-1,3-propanediol, 2-ethyl-1,3-hexanediol, 1,4-cyclohexanedimethanol (CHDM), hydrogenated bisphenol A, bisphenols represented by formula (I-1) and their derivatives: and diols represented by formula (I-2). [ka]

[0067] In equation (I-1), R is an ethylene group or a propylene group, x and y are integers greater than or equal to 0, and the average value of x + y is between 0 and 10. [ka]

[0068] In equation (I-2), R' is an ethylene group or a propylene group, x' and y' are integers greater than or equal to 0, and the average value of x'+y' is between 0 and 10.

[0069] In addition to the divalent carboxylic acid and divalent alcohol components mentioned above, the components of the polyester resin may also contain trivalent or higher carboxylic acid components and trivalent or higher alcohol components. There are no particular limitations on the carboxylic acid component with a valency of three or higher, but examples include trimellitic acid, trimellitic anhydride, and pyromellitic acid. Examples of alcohol components with a valency of three or higher include trimethylolpropane, pentaerythritol, and glycerin.

[0070] In addition to the compounds mentioned above, the polyester resin may also contain monovalent carboxylic acid components and monovalent alcohol components. Specifically, examples of monovalent carboxylic acid components include palmitic acid, stearic acid, arachidic acid, behenic acid, cerotic acid, heptacosanoic acid, montanic acid, melissic acid, laxeric acid, tetracontanoic acid, and pentacontanoic acid. Other examples of monohydric alcohol components include behenyl alcohol, ceryl alcohol, melicyl alcohol, and tetracontanol.

[0071] Toner is a one-component magnetic toner, a one-component non-magnetic toner, and a non-magnetic developer contained in a two-component developer. It can be used as any of the toner cartridges. When used as a magnetic single-component toner, magnetic iron oxide particles are preferably used as the colorant. Examples of magnetic iron oxide particles contained in the magnetic single-component toner include magnetic iron oxides such as magnetite, maghemite, and ferrite, and magnetic iron oxides containing other metal oxides; metals such as Fe, Co, and Ni; or alloys of these metals with metals such as Al, Co, Cu, Pb, Mg, Ni, Sn, Zn, Sb, Be, Bi, Cd, Ca, Mn, Se, Ti, W, and V; and mixtures thereof. The content of magnetic iron oxide particles is preferably 30 parts by mass or more and 150 parts by mass or less per 100 parts by mass of the binder resin.

[0072] Examples of colorants used as non-magnetic toners when contained in non-magnetic one-component toners and two-component developers include the following: As black pigments, carbon blacks such as furnace black, channel black, acetylene black, thermal black, and lamp black are used, as well as magnetic powders such as magnetite and ferrite. Suitable colorants for the yellow color include pigments or dyes. Examples of pigments include CI Pigment Yellow 1, 2, 3, 4, 5, 6, 7, 10, 11, 12, 13, 14, 15, 17, 23, 62, 65, 73, 74, 81, 83, 93, 94, 95, 97, 98, 109, 110, 111, 117, 120, 127, 128, 129, 137, 138, 139, 147, 151, 154, 155, 167, 168, 173, 174, 176, 180, 181, 183, 191, and CI Bat Yellow 1, 3, 20. Examples of dyes include CI Solvent Yellow 19, 44, 77, 79, 81, 82, 93, 98, 103, 104, 112, and 162. These can be used individually or in combination of two or more.

[0073] Suitable colorants for cyan include pigments or dyes. Examples of pigments include CI Pigment Blue 1, 7, 15, 15;1, 15;2, 15;3, 15;4, 16, 17, 60, 62, 66, etc., CI Bat Blue 6, and CI Acid Blue 45. Examples of dyes include CI Solvent Blue 25, 36, 60, 70, 93, 95, etc. These can be used individually or in combination of two or more. Suitable colorants for magenta include pigments or dyes. Examples of pigments include CI Pigment Red 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 21, 22, 23, 30, 31, 32, 37, 38, 39, 40, 41, 48, 48; 2, 48; 3, 48; 4, 49, 50, 51, 52, 53, 54, 55, 57, 57; 1, 58, 60, 63, 64, 68, Examples include 81, 81; 1, 83, 87, 88, 89, 90, 112, 114, 122, 123, 144, 146, 150, 163, 166, 169, 177, 184, 185, 202, 206, 207, 209, 220, 221, 238, 254, etc., as well as CI Pigment Violet 19; CI Bat Red 1, 2, 10, 13, 15, 23, 29, 35. Examples of magenta dyes include oil-soluble dyes such as CI Solvent Red 1, 3, 8, 23, 24, 25, 27, 30, 49, 52, 58, 63, 81, 82, 83, 84, 100, 109, 111, 121, 122, etc., CI Disperse Red 9, CI Solvent Violet 8, 13, 14, 21, 27, etc., and CI Disperse Violet 1, etc., as well as basic dyes such as CI Basic Red 1, 2, 9, 12, 13, 14, 15, 17, 18, 22, 23, 24, 27, 29, 32, 34, 35, 36, 37, 38, 39, 40, etc., and CI Basic Violet 1, 3, 7, 10, 14, 15, 21, 25, 26, 27, 28. These can be used individually or in combination of two or more. The coloring agent content is preferably 1 part by mass or more and 20 parts by mass or less per 100 parts by mass of the binder resin.

[0074] A release agent (wax) may be used to give the toner release properties. Examples of waxes include: aliphatic hydrocarbon waxes such as low molecular weight polyethylene, low molecular weight polypropylene, olefin copolymers, microcrystalline wax, paraffin wax, and Fischer-Tropsch wax; oxidized forms of aliphatic hydrocarbon waxes such as oxidized polyethylene wax; waxes mainly composed of fatty acid esters such as carnauba wax, behenyl behenate, and montanate ester wax; and waxes in which fatty acid esters have been partially or completely deoxidized, such as deoxidized carnauba wax. Furthermore, saturated linear fatty acids such as palmitic acid, stearic acid, and montanic acid; unsaturated fatty acids such as brassic acid, eleostearic acid, and valinalic acid; saturated alcohols such as stearyl alcohol, aralkyl alcohol, behenyl alcohol, carnaubyl alcohol, ceryl alcohol, and melissyl alcohol; polyhydric alcohols such as sorbitol; fatty acid amides such as linoleic acid amide, oleic acid amide, and lauric acid amide; saturated fatty acid bisamides such as methylenebisstearate, ethylenebiscaprate, ethylenebislaurate, and hexamethylenebisstearate; ethylenebisoleamide, hexamethylenebisoleamide, N,N Examples include unsaturated fatty acid amides such as '-dioleyl adipic acid amide and N,N'-dioleyl sebacin acid amide; aromatic bisamides such as m-xylene bisstearamide and N,N'-distearyl isophthalic acid amide; fatty acid metal salts (generally known as metal soaps) such as calcium stearate, calcium laurate, zinc stearate, and magnesium stearate; waxes grafted onto aliphatic hydrocarbon waxes with vinyl copolymer monomers such as styrene and acrylic acid; partially esterified fatty acids and polyhydric alcohols such as behenic acid monoglyceride; and methyl ester compounds having hydroxyl groups obtained by hydrogenation of vegetable oils and fats.

[0075] Particularly preferred waxes are aliphatic hydrocarbon waxes. For example, preferred waxes include low molecular weight hydrocarbons obtained by radical polymerization of alkylenes under high pressure or polymerization of Ziegler catalysts or metallocene catalysts under low pressure; Fischer-Tropsch waxes synthesized from coal or natural gas; paraffin waxes; olefin polymers obtained by thermal decomposition of high molecular weight olefin polymers; synthetic hydrocarbon waxes obtained from the distillation residue of hydrocarbons obtained by the Aage process from synthesis gas containing carbon monoxide and hydrogen, or synthetic hydrocarbon waxes obtained by hydrogenation of these.

[0076] Furthermore, it is more preferable to use hydrocarbon waxes that have been separated by methods such as press efflorescence, solvent method, vacuum distillation, or fractional crystallization. In particular, among paraffin waxes, n-paraffin wax and Fischer-Tropsch wax, which mainly consist of linear components, are preferred from the viewpoint of molecular weight distribution. These waxes may be used individually or in combination of two or more types. Preferably, the wax is added in an amount of 1 to 20 parts by mass per 100 parts by mass of the binder resin.

[0077] A charge control agent may be used in the toner. Known charge control agents can be used. Examples include azo iron compounds, azo chromium compounds, azo manganese compounds, azo cobalt compounds, azo zirconium compounds, chromium compounds of carboxylic acid derivatives, zinc compounds of carboxylic acid derivatives, aluminum compounds of carboxylic acid derivatives, and zirconium compounds of carboxylic acid derivatives. The carboxylic acid derivative is preferably an aromatic hydroxycarboxylic acid. A charge-controlling resin can also be used. If necessary, one or more charge-controlling agents may be used in combination. It is preferable to use the charge-controlling agent in an amount of 0.1 parts by mass to 10 parts by mass per 100 parts by mass of the binder resin.

[0078] The toner may be mixed with a magnetic carrier and used as a two-component developer. As the magnetic carrier, ordinary magnetic carriers such as ferrite and magnetite, or resin-coated carriers can be used. Alternatively, magnetic material-dispersed resin particles, in which magnetic material powder is dispersed in the resin component, or porous magnetic core particles containing resin in the voids can be used.

[0079] Various magnetic iron compound particle powders can be used as magnetic material components in magnetic material-dispersed resin particles, including magnetite particle powder, maghemite particle powder, or magnetic iron oxide particle powder containing at least one selected from silicon oxide, silicon hydroxide, aluminum oxide, and aluminum hydroxide; magnetoplanvite-type ferrite particle powder containing barium, strontium, or barium-strontium; and spinel-type ferrite particle powder containing at least one selected from manganese, nickel, zinc, lithium, and magnesium.

[0080] Furthermore, in addition to magnetic components, non-magnetic inorganic compound particle powders such as hematite particle powder, non-magnetic hydrated ferric oxide particle powder, goethite particle powder, titanium oxide particle powder, silica particle powder, talc particle powder, alumina particle powder, barium sulfate particle powder, barium carbonate particle powder, cadmium yellow particle powder, calcium carbonate particle powder, and zinc oxide particle powder may be used in combination with magnetic iron compound particle powder.

[0081] Examples of materials for porous magnetic core particles include magnetite or ferrite. A specific example of ferrite is shown by the following general formula. (M12O) x (M2O) y (Fe2O3) Z In the above equation, M1 is a monovalent metal and M2 is a divalent metal. When x + y + z = 1.0, x and y are 0 ≤ (x, y) ≤ 0.8, and z is 0.2. <z<1.0である) In the formula, it is preferable to use at least one metal atom selected from the group consisting of Li, Fe, Mn, Mg, Sr, Cu, Zn, and Ca as M1 and M2. Other metals that can be used include Ni, Co, Ba, Y, V, Bi, In, Ta, Zr, B, Mo, Na, Sn, Ti, Cr, Al, Si, and rare earth elements.

[0082] The magnetic carrier preferably has magnetic carrier core particles and a resin coating layer on the surface of the magnetic carrier core particles as a resin-coated carrier. The resin coating layer, for example, coats the surface of the magnetic carrier core particles. The magnetic carrier core particles are preferably porous magnetic core particles that contain resin in their voids. Either a thermoplastic resin or a thermosetting resin may be used to fill the voids in the porous magnetic core particles. Examples of thermoplastic resins used for filling include: novolac resin, saturated alkyl polyester resin, polyarylate, polyamide resin, and acrylic resin. Examples of thermosetting resins include phenolic resins, epoxy resins, unsaturated polyester resins, and silicone resins.

[0083] The method for coating the surface of magnetic carrier core particles with resin is not particularly limited, but examples include immersion, spraying, brush application, and application methods such as a fluidized bed. Among these, the immersion method is preferred. The amount of resin coating the surface of the magnetic carrier core particles (amount of resin coating layer) is preferably 0.1 parts by mass or more and 5.0 parts by mass or less per 100 parts by mass of magnetic carrier core particles in order to control the ability to impart charge to the toner.

[0084] Resins used in the resin coating layer include acrylic acid ester copolymers and methacrylate Examples include acrylic resins such as ster copolymers, styrene-acrylic resins such as styrene-acrylic ester copolymers and styrene-methacrylic ester copolymers, fluorine-containing resins such as polytetrafluoroethylene, tetrafluoroethylene-hexafluoropropylene copolymers, monochlorotrifluoroethylene polymers, and polyvinylidene fluoride, as well as silicone resins, polyester resins, polyamide resins, polyvinyl butyral, aminoacrylate resins, iomonomer resins, and polyphenylene sulfide resins. These resins can be used individually or in combination. Acrylic resins are preferred.

[0085] Among these, a copolymer containing a (meth)acrylic acid ester having an alicyclic hydrocarbon group is particularly preferred from the viewpoint of electrostatic stability. It is preferable that the resin in the resin coating layer has monomer units of a (meth)acrylic acid ester having an alicyclic hydrocarbon group. That is, the resin in the resin coating layer contains a polymer of monomers including at least a (meth)acrylic acid ester having an alicyclic hydrocarbon group. (Meth)acrylic acid esters having an alicyclic hydrocarbon group are preferably, for example, cyclobutyl acrylate, cyclopentyl acrylate, cyclohexyl acrylate, cycloheptyl acrylate, dicyclopentenyl acrylate, dicyclopentanyl acrylate, cyclobutyl methacrylate, cyclopentyl methacrylate, cyclohexyl methacrylate, cycloheptyl methacrylate, dicyclopentenyl methacrylate, and dicyclopentanyl methacrylate. The alicyclic hydrocarbon group is preferably a cycloalkyl group, with 3 to 10 carbon atoms, and more preferably 4 to 8 carbon atoms. One or more of these may be selected and used. The resin used in the resin coating layer can be identified by means such as NMR.

[0086] Furthermore, the content of monomer units made of (meth)acrylic acid ester having alicyclic hydrocarbon groups in the copolymer used in the resin coating layer (copolymerization ratio based on the mass of (meth)acrylic acid ester) is preferably 5.0% by mass or more and 80.0% by mass or less, more preferably 50.0% by mass or more and 80.0% by mass or less, and even more preferably 70.0% by mass or more and 80.0% by mass or less. Within the above range, good electrostatic stability in high temperature and high humidity environments is achieved.

[0087] Furthermore, from the viewpoint of charge stability, it is more preferable that the resin in the resin coating layer contains macromonomers as copolymer components in order to improve adhesion between the magnetic carrier core particles and the resin coating layer and to suppress local peeling of the resin coating layer. An example of a specific macromonomer is shown in formula (B). That is, it is preferable that the resin in the resin coating layer has monomer units made up of macromonomers represented by the following formula (B). [ka]

[0088] In formula (B), A represents a polymer of at least one compound selected from the group consisting of methyl acrylate, methyl methacrylate, butyl acrylate, butyl methacrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, styrene, acrylonitrile, and methacrylonitrile. 6 It is either H or CH3. A is preferably a polymer of methyl methacrylate.

[0089] In order to improve the adhesion between the magnetic carrier core particles and the resin coating layer, macromonomers The weight-average molecular weight is preferably 3,000 to 10,000, and more preferably 4,000 to 7,000.

[0090] In order to improve the adhesion between the magnetic carrier core particles and the resin coating layer, the content of monomer units by macromonomers in the resin used in the resin coating layer is preferably 0.5% by mass or more and 30.0% by mass or less, more preferably 10.0% by mass or more and 30.0% by mass or less, and even more preferably 20.0% by mass or more and 25.0% by mass or less.

[0091] <Measurement of weight-average molecular weight of macromonomers> The weight-average molecular weight is measured using gel permeation chromatography (GPC) following the procedure below. First, the sample to be measured is prepared as follows. The sample (the coating resin separated from the magnetic carrier and separated using a preparative apparatus) was mixed with tetrahydrofuran (THF) at a concentration of 5 mg / ml and allowed to stand at room temperature for 24 hours to dissolve the sample in THF. The mixture was then passed through a sample processing filter (Myshori Disc H-25-2, manufactured by Tosoh Corporation) to be used as the GPC sample. Next, using a GPC measuring device (HLC-8120GPC, manufactured by Tosoh Corporation), measurements are performed under the following conditions, in accordance with the device's operation manual. (Measurement conditions) Equipment: High-speed GPC "HLC8120 GPC" (manufactured by Tosoh Corporation) Columns: Shodex KF-801, 802, 803, 804, 805, 806, 807 (7 columns, manufactured by Showa Denko) Eluent:THF Flow rate: 1.0ml / min Oven temperature: 40.0℃ Sample injection volume: 0.10 ml

[0092] Furthermore, in calculating the weight-average molecular weight of the sample, the calibration curve used is a molecular weight calibration curve created using standard polystyrene resins (TSK Standard Polystyrene F-850, F-450, F-288, F-128, F-80, F-40, F-20, F-10, F-4, F-2, F-1, A-5000, A-2500, A-1000, A-500, manufactured by Tosoh Corporation).

[0093] The toner has toner particles and silica fine particles A on the surface of the toner particles. The toner can be obtained by adding silica fine particles A as an external additive to the toner particles. The content of silica fine particles A in the toner is preferably 0.01 to 10.00 parts by mass, more preferably 0.20 to 3.00 parts by mass, even more preferably 0.40 to 2.00 parts by mass, even more preferably 0.50 to 1.50 parts by mass, and even more preferably 0.80 to 1.20 parts by mass per 100 parts by mass of toner particles. This allows the silica fine particles A to more adequately coat the toner particles, resulting in better charge stability and suppression of material contamination. The content of silica microparticles A can be measured using the method for separating silica microparticles from toner particles as described above.

[0094] External additives such as silica microparticles A and silica microparticles B can be added to toner particles by mixing the toner particles and the external additives using a mixer like the one described below. Examples of mixing machines include: Henschel mixer (manufactured by Mitsui Mining Co., Ltd.); Super Mixer (manufactured by Kawata Co., Ltd.); Ribocone (manufactured by Okawara Seisakusho Co., Ltd.); Nauter mixer, Turbulizer, Cyclomix (manufactured by Hosokawa Micron Co., Ltd.); Spiral Pin Mixer - (Manufactured by Taiheiyo Kiko Co., Ltd.); Redigeg mixer (Manufactured by Matsubo Co., Ltd.).

[0095] In the process of obtaining toner particles, the method for producing toner particles is not particularly limited and can be produced by known methods. Examples include grinding, emulsification and agglutination, suspension polymerization, and dissolution and suspension methods.

[0096] Toner particles produced by the pulverization method are manufactured, for example, as follows: The binder resin, colorant, and other additives as needed are thoroughly mixed using a mixer such as a Henschel mixer or ball mill. The mixture is then melt-kneaded using a thermal kneader such as a twin-screw extruder, heated roll, kneader, or extruder. At this stage, wax, magnetic iron oxide particles, and metal-containing compounds may also be added. After the molten mixture is cooled and solidified, it is crushed and classified to obtain toner particles. The toner particles and external additives such as silica fine particles A are mixed using a mixer such as a Henschel mixer to obtain toner.

[0097] Examples of mixing machines include: Henschel mixer (manufactured by Mitsui Mining Co., Ltd.); Super Mixer (manufactured by Kawata Co., Ltd.); Ribocone (manufactured by Okawara Seisakusho Co., Ltd.); Nauter mixer, Turbulizer, Cyclomix (manufactured by Hosokawa Micron Co., Ltd.); Spiral Pin Mixer (manufactured by Taiheiyo Kiko Co., Ltd.); and Redigge mixer (manufactured by Matsubo Co., Ltd.).

[0098] Examples of mixing machines include: KRC kneader (manufactured by Kurimoto Iron Works); Buss-Co kneader (manufactured by Buss); TEM type extruder (manufactured by Toshiba Machine Co.); TEX twin-screw mixer (manufactured by Japan Steel Works); PCM mixer (manufactured by Ikegai Iron Works); three-roll mill, mixing roll mill, kneader (manufactured by Inoue Seisakusho); NideX (manufactured by Mitsui Mining Co.); MS type pressure kneader, Nidaruder (manufactured by Moriyama Seisakusho); Banbury mixer (manufactured by Kobe Steel).

[0099] Examples of crushing machines include: counter jet mill, micron jet, inomizer (manufactured by Hosokawa Micron Co., Ltd.); IDS type mill, PJM jet crusher (manufactured by Nippon Pneumatic Mfg. Co., Ltd.); cross jet mill (manufactured by Kurimoto Iron Works Co., Ltd.); Ulmax (manufactured by Nisso Engineering Co., Ltd.); SK Jet-O-Mill (manufactured by Seishin Enterprise Co., Ltd.); Cryptron (manufactured by Kawasaki Heavy Industries, Ltd.); Turbo Mill (manufactured by Turbo Industries Co., Ltd.); and Super Rotor (manufactured by Nisshin Engineering Co., Ltd.).

[0100] Furthermore, if necessary, after grinding, the toner particles can be surface-treated using a hybridization system (manufactured by Nara Machine Works), Nobilta (manufactured by Hosokawa Micron Corporation), Mechanofusion system (manufactured by Hosokawa Micron Corporation), Faculty (manufactured by Hosokawa Micron Corporation), Inomizer (manufactured by Hosokawa Micron Corporation), Theta Composer (manufactured by Tokuju Kogyo Co., Ltd.), Mechanomill (manufactured by Okada Seikou Co., Ltd.), or Meteor Rainbow MR Type (manufactured by Nippon Pneumatic Co., Ltd.).

[0101] Examples of classifiers include: Classil, Micron Classifier, Spedick Classifier (manufactured by Seishin Corporation); Turbo Classifier (manufactured by Nisshin Engineering Co., Ltd.); Micron Separator, Turboplex (ATP), TSP Separator (manufactured by Hosokawa Micron Corporation); Elbow Jet (manufactured by Nippon Steel Mining Co., Ltd.), Dispersion Separator (manufactured by Nippon Pneumatic Mfg. Co., Ltd.); and YM Microcut (manufactured by Yaskawa Trading Co., Ltd.).

[0102] Examples of sieving devices used to separate coarse particles include: Ultrasonic (manufactured by Koei Sangyo Co., Ltd.); Resona Sieve, Gyro Shifter (manufactured by Tokuju Kogyo Co., Ltd.) Vibrasonic System (manufactured by Dalton); Soniclean (manufactured by Shinto Kogyo); TurboScreener (manufactured by Turbo E-Gyo); Microshifter (manufactured by Makino Sangyo); Circular vibrating screen.

[0103] Toner particles are manufactured by emulsification and agglutination, for example, as shown below. <Process for preparing a resin fine particle dispersion (preparation process)> For example, the binder resin component is dissolved in an organic solvent to form a homogeneous solution. Then, basic compounds or surfactants are added as needed. An aqueous medium is slowly added to this solution while applying shear force using a homogenizer or the like to form resin microparticles of the binder resin. Finally, the organic solvent is removed to prepare a resin microparticle dispersion in which the resin microparticles are dispersed.

[0104] When preparing a resin fine particle dispersion, the amount of resin component to be dissolved in the organic solvent is preferably 10 parts by mass or more and 50 parts by mass or less, and more preferably 30 parts by mass or more and 50 parts by mass or less, per 100 parts by mass of the organic solvent.

[0105] Any organic solvent capable of dissolving the resin components can be used, but solvents with high solubility for olefin resins, such as toluene, xylene, and ethyl acetate, are preferred.

[0106] The surfactant is not particularly limited. Examples include anionic surfactants such as sulfate esters, sulfonates, carboxylates, phosphates, and soaps; cationic surfactants such as amine salts and quaternary ammonium salts; and nonionic surfactants such as polyethylene glycol, alkylphenol ethylene oxide adducts, and polyhydric alcohols.

[0107] Examples of basic compounds include inorganic bases such as sodium hydroxide and potassium hydroxide, and organic bases such as triethylamine, trimethylamine, dimethylaminoethanol, and diethylaminoethanol. These basic compounds may be used individually or in combination of two or more.

[0108] <Agglomeration process> The aggregation process involves, for example, mixing the resin microparticle dispersion with a coloring agent microparticle dispersion, a wax microparticle dispersion, and a silicone oil emulsion as needed to prepare a mixture, and then agglomerating the microparticles contained in the prepared mixture to form aggregate particles.

[0109] Suitable methods for forming aggregate particles include adding and mixing a flocculant into the above-mentioned mixed liquid, and then increasing the temperature or applying mechanical power as appropriate.

[0110] A dispersion of colorant microparticles is prepared by dispersing the colorant described above. The colorant microparticles are dispersed by known methods, but media-type dispersers such as rotary shear homogenizers, ball mills, sand mills, and attritors, and high-pressure opposing impact dispersers are preferably used. In addition, surfactants or polymer dispersants that impart dispersion stability can be added as needed.

[0111] Wax particulate dispersions and silicone oil emulsions are prepared by dispersing each material in an aqueous medium. Each material is dispersed by known methods, but media-type dispersers such as rotary shear homogenizers, ball mills, sand mills, and attritors, and high-pressure opposing impact dispersers are preferably used. In addition, surfactants or polymer dispersants that impart dispersion stability can be added as needed.

[0112] Examples of flocculants include monovalent metal salts such as sodium and potassium; divalent metal salts such as calcium and magnesium; trivalent metal salts such as iron and aluminum; and polyvalent metal salts such as polyaluminum chloride. From the viewpoint of particle size controllability in the flocculation process, divalent metal salts such as calcium chloride and magnesium sulfate are preferred. The addition and mixing of the flocculant is preferably carried out within a temperature range of room temperature to 75°C. Under these temperature conditions, the flocculation proceeds in a stable manner. The mixing can be carried out using known mixing devices, homogenizers, mixers, etc.

[0113] <Fusion process> The fusion process involves heating the aggregate particles to a temperature preferably above the melting point of the olefin resin and fusing them together to produce particles with a smooth surface. Before proceeding to the fusion process, chelating agents, pH adjusters, surfactants, etc., can be added as appropriate to prevent fusion between the resulting resin particles.

[0114] Examples of chelating agents include alkali metal salts such as ethylenediaminetetraacetic acid (EDTA) and its sodium salt, sodium gluconate, sodium tartrate, potassium citrate and sodium citrate, nitrilotriacetate (NTA) salts, and many water-soluble polymers (polyelectrolytes) that contain both COOH and OH functionalities. The time required for the fusion process varies depending on the heating temperature; a shorter time is sufficient at higher temperatures, while a longer time is needed at lower temperatures. In other words, the heating and fusion time cannot be precisely defined as it depends on the heating temperature, but it is generally between 10 minutes and 10 hours.

[0115] <Cooling process> This step involves cooling the temperature of the aqueous medium containing the resin particles obtained in the fusion process. While not particularly limited, the specific cooling rate is approximately 0.1 to 50°C / minute.

[0116] <Washing Process> The resin particles produced through the above process can be cleaned and filtered repeatedly to remove impurities from them. Specifically, it is preferable to wash the resin particles with an aqueous solution containing a chelating agent such as ethylenediaminetetraacetic acid (EDTA) and its sodium salt, and then wash them further with pure water. By repeatedly washing and filtering with pure water, metal salts and surfactants in the resin particles can be removed. From the viewpoint of manufacturing efficiency, 3 to 20 filtrations are preferable, and 3 to 10 filtrations are more preferable.

[0117] <Drying and classification process> Toner particles can be obtained by drying the washed resin particles and classifying them as appropriate.

[0118] Toner particles produced by the dissolution-suspension method are manufactured, for example, as follows: In the dissolution suspension method, a resin composition obtained by dissolving a binder resin component in an organic solvent is dispersed in an aqueous medium to granulate particles of the resin composition, and then the organic solvent contained in the particles of the resin composition is removed to produce toner particles. The dissolution-suspension method is applicable to any resin component that dissolves in an organic solvent, and it also allows for easy shape control depending on the conditions during solvent removal. The following describes, but is not limited to, a toner manufacturing method using the dissolution suspension method.

[0119] <Resin component dissolution process> In the resin component dissolution process, a binder resin is used, and, if necessary, a colorant, wax and silicate A resin composition is prepared by dissolving or dispersing other components, such as oil, in an organic solvent. Any organic solvent capable of dissolving the resin components can be used. Specifically, examples include toluene, xylene, chloroform, methylene chloride, and ethyl acetate. However, toluene and ethyl acetate are preferred due to their ability to promote crystallization of crystalline resins and their ease of solvent removal.

[0120] There are no restrictions on the amount of organic solvent used, but it should be an amount that allows the resin composition to disperse in a poor medium such as water and achieve a viscosity that enables granulation. Specifically, a mass ratio of the resin component, and optionally other components such as colorants, waxes, and silicone oils, to the organic solvent of 10 / 90 to 50 / 50 is preferable from the viewpoint of granulation properties and toner particle production efficiency, as described later.

[0121] On the other hand, the colorants, waxes, and silicone oils do not need to be dissolved in organic solvents; they may be dispersed. When using the colorants, waxes, and silicone oils in a dispersed state, it is preferable to disperse them using a disperser such as a bead mill.

[0122] <Granulation process> The granulation process is a step in which the obtained resin composition is dispersed in an aqueous medium using a dispersant to obtain a predetermined toner particle size, thereby preparing particles of the resin composition. Water is the primary water-based medium used. Furthermore, it is preferable that the aqueous medium contains 1% to 30% by mass of a monovalent metal salt. The presence of a monovalent metal salt suppresses the diffusion of organic solvents in the resin composition into the aqueous medium, thereby increasing the crystallinity of the resin components contained in the resulting toner particles. As a result, the toner tends to have good blocking resistance and a good particle size distribution.

[0123] Examples of monovalent metal salts include sodium chloride, potassium chloride, lithium chloride, and potassium bromide, of which sodium chloride and potassium chloride are preferred. Furthermore, the mixing ratio (mass ratio) of the aqueous medium and the resin composition is preferably aqueous medium / resin composition = 90 / 10 to 50 / 50.

[0124] The above-mentioned dispersant is not particularly limited, but as an organic dispersant, cationic, anionic, and nonionic surfactants can be used, with anionic surfactants being preferred. Examples include sodium alkylbenzene sulfonate, sodium α-olefin sulfonate, sodium alkyl sulfonate, and sodium alkyl diphenyl ether disulfonate. On the other hand, examples of inorganic dispersants include tricalcium phosphate, hydroxyapatite, calcium carbonate microparticles, titanium dioxide microparticles, and silica microparticles.

[0125] Of these, the inorganic dispersant tricalcium phosphate is preferred. This is because it has very little adverse effect on granulation properties, stability, and the characteristics of the resulting toner. The amount of dispersant added is determined according to the particle size of the granules; as the amount of dispersant added increases, the particle size decreases. For this reason, although the amount of dispersant added varies depending on the desired particle size, it is preferable to use it in the range of 0.1 to 15% by mass relative to the resin composition. Furthermore, when preparing resin composition particles in an aqueous medium, it is preferable to do so under high-speed shearing conditions. Examples of devices that provide high-speed shearing include various high-speed dispersers and ultrasonic dispersers.

[0126] <Solvent removal process> In the solvent removal process, the organic solvent contained in the particles of the obtained resin composition is removed to produce toner particles. The removal of the organic solvent is preferably carried out while stirring.

[0127] <Washing, drying, and classification process> After the solvent removal step, a washing and drying step may be performed in which the toner particles are washed multiple times with water or the like, filtered, and dried. Furthermore, if a dispersant that dissolves under acidic conditions, such as tricalcium phosphate, is used, it is preferable to wash with hydrochloric acid followed by washing with water. Washing removes the dispersant used for granulation. After washing, toner particles can be obtained by filtering and drying, and then appropriately classifying the material.

[0128] Toner particles are manufactured by suspension polymerization, for example, as shown below. A polymerizable monomer composition is prepared by uniformly dissolving or dispersing polymerizable monomers that generate a binder resin, colorants, wax components, and polymerization initiators using a disperser such as a homogenizer, ball mill, or ultrasonic disperser. After granulating the polymerizable monomer composition particles by dispersing the polymerizable monomer composition in an aqueous medium, toner particles are obtained by polymerizing the polymerizable monomers in the particles made of the polymerizable monomer composition.

[0129] In this case, it is preferable that the polymerizable monomer composition is prepared by mixing a dispersion in which a colorant is dispersed in a first polymerizable monomer (or a portion of the polymerizable monomers) with at least a second polymerizable monomer (or the remaining polymerizable monomers). That is, by thoroughly dispersing the colorant in the first polymerizable monomer and then mixing it with the second polymerizable monomer together with other toner materials, the colorant can be present in the polymerized particles in a better dispersed state.

[0130] The resulting toner particles may be filtered, washed, dried, and classified by known methods as needed.

[0131] <Process for adding external additives to toner particles> Toner can be obtained by mixing toner particles and external additives (silica microparticles A and, if necessary, silica microparticles B) using a mixer such as a Henschel mixer.

[0132] When using silica microparticles A and silica microparticles B together, silica microparticles A and B may be added to the toner particles at the same time. However, as described above, it is preferable to add silica microparticles B and silica microparticles A separately. In the step of externally adding silica fine particles B to the obtained toner particles, the silica fine particles B can be mixed with the toner particles using a mixer such as a Henschel mixer.

[0133] The weight-average particle size (D4) of the toner is 4.0 to 15.0 μm. Preferably, it is 4.0 to 9.0 μm, and more preferably 6.0 to 8.0 μm. As a result, the silica microparticles A can properly coat the toner particles, and the contact area between the silica microparticles A and the toner particles is optimized, leading to better electrostatic stability. This reduces fluctuations in image density even when the environment changes, and suppresses changes in image density during continuous printing. The weight-average particle size (D4) of the toner can be adjusted, for example, by classifying the toner particles.

[0134] <Method for measuring the weight-average particle size (D4) of toner> The weight-average particle size (D4) of the toner is measured using the "Coulter Counter Multisizer 3" (registered trademark, manufactured by Beckman Coulter), a precision particle size distribution analyzer using the pore electrical resistance method with a 100 μm aperture tube, and the accompanying dedicated software "Beckman Coulter Multisizer 3 Version 3.51" (manufactured by Beckman Coulter) for setting measurement conditions and analyzing measurement data, with an effective measurement channel count of 25,000. The measurement data is then analyzed and calculated. The electrolytic aqueous solution used for measurement is prepared by dissolving special grade sodium chloride in deionized water to a concentration of approximately 1% by mass; for example, "ISOTON II" (manufactured by Beckman Coulter) can be used. Before performing measurements and analysis, configure the dedicated software as follows. In the dedicated software's "Change Standard Measurement Method (SOM)" screen, set the total count in control mode to 50,000 particles, the number of measurements to 1, and the Kd value to the value obtained using "Standard Particle 10.0 μm" (manufactured by Beckman Coulter). Press the Threshold / Noise Level measurement button to automatically set the threshold and noise level. Also, set the current to 1600 μA, the gain to 2, the electrolyte to ISOTON II, and check the box for flushing the aperture tube after measurement. In the dedicated software's "Pulse to Particle Size Conversion Settings Screen," set the bin spacing to logarithmic particle size, the particle size bins to 256 particle size bins, and the particle size range to 2 μm or more and 60 μm or less.

[0135] The specific measurement method is as follows: (1) Pour approximately 200 ml of the electrolytic solution into a 250 ml round-bottom glass beaker specifically designed for the Multisizer 3, set it on the sample stand, and stir the mixture with the stirrer rod at 24 revolutions per second in a counterclockwise direction. Then, use the "Aperture Tube Flash" function of the dedicated software to remove any dirt and air bubbles from inside the aperture tube. (2) Place approximately 30 ml of the electrolytic aqueous solution into a 100 ml flat-bottomed glass beaker, and add approximately 0.3 ml of a diluted solution of "Contaminon N" (a 10% by mass aqueous solution of a pH 7 neutral detergent for cleaning precision measuring instruments, consisting of a nonionic surfactant, anionic surfactant, and organic builder, manufactured by Wako Pure Chemical Industries, Ltd.) diluted three times by mass with deionized water as a dispersant. (3) Two oscillators with an oscillation frequency of 50 kHz are built in with their phases shifted by 180 degrees, and a predetermined amount of deionized water is placed in the water tank of an ultrasonic dispersion device called "Ultrasonic Dispersion System Tetora150" (manufactured by Nikko Bios Co., Ltd.) with an electrical output of 120 W. Approximately 2 ml of the aforementioned Contaminon N is added to this water tank. (4) Place the beaker from (2) into the beaker fixing hole of the ultrasonic disperser and operate the ultrasonic disperser. Then, adjust the height of the beaker so that the resonance state of the liquid surface of the electrolytic aqueous solution inside the beaker is maximized. (5) While irradiating the electrolytic aqueous solution in the beaker described in (4) with ultrasound, add approximately 10 mg of toner to the electrolytic aqueous solution in small amounts and disperse it. Continue the ultrasonic dispersion treatment for another 60 seconds. During ultrasonic dispersion, adjust the water temperature in the tank to be between 10°C and 40°C as appropriate. (6) Using a pipette, the electrolytic aqueous solution (5) containing the dispersed toner is dropped into the round-bottom beaker (1) placed in the sample stand, and the concentration is adjusted to approximately 5%. The measurement is then continued until the number of particles measured reaches 50,000. (7) The measurement data is analyzed using the dedicated software attached to the device, and the weight-average particle size (D4) is calculated. Note that the "Average Diameter" on the Analysis / Volume Statistics (Arithmetic Mean) screen when the dedicated software is set to Graph / Volume % is the weight-average particle size (D4). [Examples]

[0136] The basic structure and features of this disclosure have been described above; the disclosure will now be explained in detail based on examples. However, this disclosure is not limited to these examples. Unless otherwise specified, parts and percentages are based on mass. Examples 7 to 18 below are referred to as Reference Examples 7 to 18, respectively.

[0137] <Example of manufacturing of binder resin 1> • Bisphenol A ethylene oxide (2.2 molar adduct): 50.0 molar parts • Bisphenol A propylene oxide (2.2 molar adduct): 50.0 molar parts Terephthalic acid: 90.0 molar parts • Trimellitus anhydride: 10.0 moles 100 parts by mass of the monomer constituting the above polyester unit was mixed with 500 ppm of titanium tetrabutoxide in a 5-liter autoclave. A reflux condenser, moisture separator, N2 gas introduction tube, thermometer, and stirring device were attached to the autoclave, and a condensation polymerization reaction was carried out at 230°C while introducing N2 gas into the autoclave. The reaction time was adjusted to achieve the desired softening point, and after the reaction was completed, the material was removed from the container, cooled, and pulverized to obtain binder resin 1. The softening point of binder resin 1 was 130°C, and the Tg was 57°C. The softening point was measured as follows:

[0138] (Measurement of softening point) The softening point is measured using a constant-load extrusion type capillary rheometer, the "Flow Characteristics Evaluation Device Flow Tester CFT-500D" (manufactured by Shimadzu Corporation), according to the manual included with the device. With this device, a constant load is applied from the top of the sample by a piston, the sample filled in the cylinder is heated and melted, and the molten sample is extruded from a die at the bottom of the cylinder. A flow curve showing the relationship between the piston descent amount and temperature can be obtained. The softening point is defined as the "melting temperature in the 1 / 2 method" as described in the manual included with the "Flow Characteristics Evaluation Device Flow Tester CFT-500D". The melting temperature in the 1 / 2 method was calculated as follows:

[0139] First, we calculate half the difference between the piston's descent Smax at the end of the outflow and the piston's descent Smin at the start of the outflow (let's call this X; X = (Smax - Smin) / 2). Then, the temperature on the flow curve when the piston's descent is the sum of X and Smin is the melting temperature using the 1 / 2 method. The sample used for measurement is approximately 1.3 g of sample, compressed at 10 MPa for 60 seconds at 25°C using a tablet molding compressor (e.g., NT-100H, manufactured by NPA Systems Co., Ltd.) to form a cylindrical shape with a diameter of approximately 8 mm. The measurement conditions for CFT-500D are as follows: Test mode: Temperature increase method Starting temperature: 50℃ Achieved temperature: 200℃ Measurement interval: 1.0℃ Heating rate: 4.0℃ / min Piston cross-sectional area: 1,000 cm² 2 Test load (piston load): 10.0 kgf / cm 2 (0.9807 MPa) Preheating time: 300 seconds Die hole diameter: 1.0mm Die length: 1.0mm

[0140] <Example of manufacturing silica microparticle A1> BET specific surface area 145m 2 500 g of fumed silica (silica microparticle substrate) at a concentration of / g was placed in a reaction vessel and heated under nitrogen purging and stirring, with the temperature inside the reaction vessel controlled to 330°C. Next, as a surface treatment agent, octamethylcyclotetrasiloxane was supplied into the reaction vessel in vapor form at a rate of 10 g / min for 60 minutes, followed by heating and stirring for 180 minutes to surface treat the silica microparticle substrate. After removing the unreacted surface treatment agent, polydimethylsiloxane (kinematic viscosity at 25°C: 100 mm) was added under stirring with nitrogen purging. 2 A solution prepared by diluting 50 g of silica ( / s) with 500 g of hexane was sprayed onto the surface, and then heated and stirred for 120 minutes to obtain silica nanoparticles A1. Table 1 shows the treatment conditions for the first stage, and Table 2 shows the treatment conditions for the second stage and the physical properties of silica nanoparticles A1.

[0141] <Manufacturing examples of silica microparticles A2-17> As shown in Tables 1 and 2, silica nanoparticles A2 to A17 were obtained by manufacturing them in the same manner as silica nanoparticle A1, except that the fumed silica (silica nanoparticle substrate), surface treatment agent, and treatment conditions were changed. The physical properties of silica nanoparticles A2 to A17 are shown in Table 2.

[0142] <Example of manufacturing silica microparticles B1> 500g of fumed silica (silica microparticle substrate) with an average particle size of 120nm was placed in a stainless steel (SUS304) reaction vessel connected to a vacuum pump. The pressure inside the reaction vessel was reduced to 0.001Pa, and the mixture was heated and stirred to control the temperature of the reaction vessel to 330°C. After a 30-minute degassing treatment in this state, octamethylcyclotetrasiloxane vapor was introduced as a surface treatment agent, supplied at a rate of 6 g / min, while the valve opening between the vacuum pump and the reaction vessel was adjusted to control the pressure inside the reaction vessel to 1 Pa. In this state, the silica nanoparticle substrate was surface-treated by heating and stirring for 20 minutes. The total amount of octamethylcyclotetrasiloxane introduced in this process was 120 g. Subsequently, the reaction vessel was evacuated under reduced pressure to 0.001 Pa to remove the reaction products and unreacted surface treatment agent. After 30 minutes of degassing in this state, octamethylcyclotetrasiloxane vapor was again introduced as the surface treatment agent, supplied at a rate of 6 g / min while controlling the pressure in the reaction vessel to 1 Pa. In this state, the silica nanoparticles were subjected to a second surface treatment by heating and stirring for 20 minutes. The total amount of octamethylcyclotetrasiloxane introduced in this process was 120 g. After a 30-minute degassing treatment in this state, octamethylcyclotetrasiloxane vapor was introduced again as a surface treatment agent, supplied at a rate of 6 g / min, while controlling the pressure inside the reaction vessel to 1 Pa. In this state, heating and stirring were performed for 20 minutes to perform a third surface treatment on the silica nanoparticles. The total amount of octamethylcyclotetrasiloxane introduced in this process was 120 g. Subsequently, while continuing heating and stirring, the reaction vessel was evacuated under reduced pressure to 0.001 Pa to remove unreacted surface treatment agent, and silica nanoparticles B1 were obtained. [Table 1] In Tables 1 and 2-1, the amount (parts) of the treatment agent is given for the surface of 100 parts by mass of silica fine particle substrate. This indicates the mass parts of the treatment agent. [Table 2-1] [Table 2-2] In Table 2-2, SD1 represents the peak corresponding to silicon atoms with a D1 unit structure, SD2 represents the peak corresponding to silicon atoms with a D2 unit structure, and particle size represents the number-average particle size (nm).

[0143] <Example 1> • Binding resin 1,100 units • Paraffin wax (melting point 78°C) 4 parts • Carbon Black (Nipex35) 6 parts The above materials were pre-mixed using a Henschel mixer (product name: FM-10C, manufactured by Nippon Coke Co., Ltd.), and then melt-kneaded at 160°C using a twin-screw kneading extruder. The resulting mixture was cooled, coarsely ground in a hammer mill, and then finely ground in a turbo mill. The obtained finely ground material was classified using a multi-segment classifier utilizing the Coanda effect to obtain toner particles 1 with a weight-average particle size (D4) of 6.5 μm.

[0144] The obtained toner particles 1 were subjected to external treatment with silica fine particles A1 and B1 as described below. • Toner particles 1: 100 copies • Silica microparticles A1: 1.0 part • Silica microparticles B1: 1.0 part The above ingredients were mixed using a Henschel mixer (product name: FM-10C, manufactured by Nippon Coke Co., Ltd.) at a rotation speed of 67 seconds. -1 After mixing at room temperature with a rotation time of 2 minutes at 4000 rpm, the mixture was passed through an ultrasonic vibrating sieve with a mesh size of 54 μm to obtain toner 1.

[0145] <Example of manufacturing magnetic carrier core particle 1> Process 1 (Weighing and Mixing Process) Fe2O368.3% by mass MnCO328.5% by mass Mg(OH)22.0% by mass SrCO31.2% by mass The above ferrite raw materials were weighed, and 20 parts water was added to 80 parts ferrite raw materials. Then, a slurry was prepared by wet mixing for 3 hours using a zirconia ball mill with a diameter (φ) of 10 mm. The solid content concentration of the slurry was 80% by mass.

[0146] Step 2 (Calibration Process) After drying the mixed slurry using a spray dryer (manufactured by Okawara Chemical Machinery Co., Ltd.), calcined ferrite was produced by firing it in a batch-type electric furnace under a nitrogen atmosphere (oxygen concentration 1.0 vol%) at a temperature of 1050°C for 3.0 hours.

[0147] Step 3 (Grinding Process) Calcined ferrite was crushed to approximately 0.5 mm using a crusher, and then water was added to prepare a slurry. The solid content concentration of the slurry was set to 70% by mass. This slurry was then ground for 3 hours in a wet ball mill using 1 / 8-inch stainless steel beads to obtain a slurry. This slurry was further ground for 4 hours in a wet bead mill using 1 mm diameter zirconia to obtain a calcined ferrite slurry with a volume-based 50% particle size (D50) of 1.3 μm.

[0148] Process 4 (granulation process) To 100 parts of the above calcined ferrite slurry, 1.0 part of ammonium polycarboxylate was added as a dispersant and 1.5 parts of polyvinyl alcohol was added as a binder. The mixture was then granulated into spherical particles using a spray dryer (manufactured by Okawara Chemical Machinery Co., Ltd.) and dried. After adjusting the particle size of the resulting granules, the mixture was heated in a rotary electric furnace at 700°C for 2 hours to remove organic matter such as dispersants and binders.

[0149] Step 5 (Baking process) Under a nitrogen atmosphere (oxygen concentration 1.0 vol%), the granules were fired by raising the temperature from room temperature to the firing temperature (1100°C) in 2 hours, and then maintaining the temperature at 1100°C for 4 hours. After that, the temperature was lowered to 60°C over 8 hours, the atmosphere was returned from nitrogen to air, and the fired material was removed at a temperature of 40°C or lower.

[0150] Process 6 (Sorting Process) After crushing the aggregated particles in the resulting calcined material, coarse particles were removed by sieving with a 150 μm mesh sieve, fine powder was removed by air classification, and low magnetic force components were further removed by magnetic separation to obtain porous magnetic core particles.

[0151] Process 7 (filling process) 100 parts of porous magnetic core particles 1 were placed in the stirring container of a mixing and stirring machine (Dalton NDMV type universal stirring machine), and 5 parts of a filling resin consisting of methyl silicone oligomer: 95.0% by mass and γ-aminopropyltrimethoxysilane: 5.0% by mass were added dropwise at atmospheric pressure while maintaining a temperature of 60°C.

[0152] After the dropping was complete, stirring was continued while adjusting the time, and the temperature was raised to 70°C to fill the particles of each porous magnetic core with the resin composition. The resin-filled magnetic core particles obtained after cooling were transferred to a mixer with spiral blades (Drum mixer UD-AT type manufactured by Sugiyama Heavy Industries Co., Ltd.) in a rotatable mixing container, and the temperature was raised to 140°C while stirring at a heating rate of 2°C / min under a nitrogen atmosphere. After that, the mixture was heated at 140°C for 50 minutes. Continue heating and stirring for 1 minute. The ferrite particles were then cooled to room temperature, filled with resin, and hardened. Non-magnetic materials were removed using a magnetic separator. Coarse particles were then removed using a vibrating screen to obtain resin-filled magnetic carrier core particles 1.

[0153] (Examples of coating resin manufacturing) • Cyclohexyl methacrylate monomer 26.8% by mass • Methyl methacrylate monomer 0.2% by mass • Methyl methacrylate macromonomer 8.4% by mass (a macromonomer with a weight-average molecular weight of 5000 and a methacryloyl group at one end) (Represented by formula (B), where A is a polymer of methyl methacrylate.) • Toluene 31.3% by mass • Methyl ethyl ketone 31.3% by mass • Azobisisobutyronitrile 2.0% by mass Of the above materials, cyclohexyl methacrylate monomer, methyl methacrylate monomer, methyl methacrylate macromonomer, toluene, and methyl ethyl ketone were placed in a four-necked separable flask equipped with a reflux condenser, thermometer, nitrogen inlet tube, and stirrer. After introducing nitrogen gas into the separable flask to create a sufficient nitrogen atmosphere, the mixture was heated to 80°C, azobisisobutyronitrile was added, and polymerization was carried out under reflux for 5 hours. Hexane was injected into the resulting reactant to precipitate the copolymer. The resulting precipitate was filtered off and then vacuum-dried to obtain the resin. Thirty parts of the resin were dissolved in a mixed solvent of 40 parts toluene and 30 parts methyl ethyl ketone to obtain a resin solution (solid content concentration 30%).

[0154] (Preparation Example of Coated Resin Solution) · Resin solution (solid content concentration 30%) 33.3 mass% · Toluene 66.4 mass% · Carbon black (Regal330; manufactured by Cabot Corporation) 0.3 mass% (number average particle size of primary particles: 25 nm, nitrogen adsorption specific surface area: 94 m 2 / g, DBP oil absorption: 75 ml / 100 g) The above materials were put into a paint shaker and dispersed for 1 hour using zirconia beads with a diameter of 0.5 mm. The obtained dispersion was filtered through a 5.0 μm membrane filter to obtain a coated resin solution.

[0155] (Manufacturing Example of Magnetic Carrier 1) The coated resin solution and magnetic carrier core particles were put into a vacuum degassing kneader maintained at room temperature (the input amount of the coated resin solution was 2.5 parts as the resin component with respect to 100 parts of magnetic carrier core particles 1). After the input, it was stirred at a rotational speed of 30 rpm for 15 minutes. After the solvent volatilized to a certain level (80% or more), it was heated to 80 °C while mixing under reduced pressure, and after distilling off toluene over 2 hours, it was cooled. The obtained magnetic carrier was separated into low magnetic products by magnetic separation, passed through a sieve with an aperture of 70 μm, and then classified by an air classifier to obtain magnetic carrier 1 with a 50% particle size (D50) of 38.2 μm based on volume distribution.

[0156] (Preparation Example and Evaluation of Two-Component Developer 1) Toner 1 and magnetic carrier 1 were added so that the toner concentration became 8.0 mass%, and using a V-type mixer (V-10 type: manufactured by Tokuju Seisakusho Co., Ltd.), 0.5 s -1 and mixed under the condition of a rotation time of 5 minutes to prepare two-component developer 1. The following evaluation was carried out using the obtained two-component developer 1.

[0157] (Evaluation) As an image forming apparatus, imagePRESS C850 (manufactured by Canon) was used. The fixing unit was taken out externally so that the fixing temperature could be arbitrarily controlled, and the apparatus was modified so that an image forming speed of 105 sheets / min for A4 size could be achieved. Also, the developing contrast was made adjustable to an arbitrary value, and the automatic correction by the main body was made inoperative. Further, the frequency of the alternating electric field was fixed at 2.0 kHz, and the voltage between peaks (Vpp) was made changeable in steps of 0.1 kV from 0.7 kV to 1.8 kV.

[0158] Two-component developer 1 was put into the developer at the black position of this image forming apparatus, and the charging voltage VD of the electrostatic latent image carrier and the laser power were adjusted, and the evaluations described below were performed. For each evaluation, evaluations were carried out at two levels where the image forming speed was 105 sheets / min for A4 size and the image forming speed was 85 sheets / min for A4 size. As the evaluation paper, white paper (product name: CS-814 (A4, 81.4 g / m 2 ), Canon Marketing Japan Inc.) was used. Also, in the following evaluations, the FFH image is a value obtained by displaying 256 gradations in hexadecimal, 00H is the first gradation (white background part) of 256 gradations, and FFH is the 256th gradation (solid part) of 256 gradations.

[0159] <Evaluation of environmental dependence> In a normal temperature and normal humidity environment (temperature 23°C / humidity 50RH%, hereinafter also referred to as "N / N environment"), the developing contrast of the copying machine main body was adjusted, and the reflection density of the image output as the FFH image was measured with an optical densitometer, and it was set so that the reflection density became 1.50. Under the above image forming conditions, 5 images were output, the density of the output images was measured, the arithmetic mean of the densities was obtained, and the image density A was obtained. Next, in a high temperature and high humidity environment (temperature 30°C / humidity 80RH%, hereinafter also referred to as "H / H environment"), the copying machine main body was left in the H / H environment for 24 hours with the developing contrast set in N / N. Then, 5 images were output, the density of the output images was measured, the arithmetic mean of the densities was obtained, and the image density B was obtained. For the optical densitometer used, we employed the X-Rite color reflectance densitometer (manufactured by X-Rite). Then, the density fluctuation difference shown in the following formula was calculated, and the image density stability was evaluated using the density fluctuation difference. Images with a density fluctuation difference of less than 0.18 were judged to be good. Density variation difference = |Image density A - Image density B| A: Less than 0.06 B: 0.06 or higher and less than 0.10 C: 0.10 or higher, less than 0.14 D: 0.14 or higher, less than 0.18 E: 0.18 or higher

[0160] <Evaluation of stability over time> Under N / L conditions, the initial Vpp was fixed at 1.3kV, and the contrast potential was set so that the reflectance density of the black monochrome FFH image was 1.50. With this setting, 2000 image patterns with a black monochrome image ratio of 1% to the paper surface were output consecutively. Then, with Vpp set to 1.3kV, the black monochrome FFH image was output again, and the reflectance density was measured. The contrast potential at which the reflectance density of the black monochrome FFH image output was 1.50 was determined, and the difference between the initial and post-output values ​​was compared. The reflectance density was measured using a 500 series spectrophotometer (X-Rite). Criteria for evaluating developability A: The difference between the initial voltage and the output voltage is less than 40V. B: The difference between the initial voltage and the output voltage is between 40V and 60V. C: The difference between the initial voltage and the output voltage is between 60V and 80V. D: The difference between the initial voltage and the output voltage is between 80V and 100V. E: The difference between the initial voltage and the output voltage is 100V or more.

[0161] <Evaluation of transcription omissions> Under H / H conditions, the development contrast of the copier was adjusted, and the reflectance density of the output FFH image was measured using an optical densitometer, setting it to 1.50. With this setting, 50,000 image patterns with a black monochrome image ratio of 1% to the paper surface were output consecutively. Then, one 500 μm horizontal line pattern was output, and the fine lines were magnified using a digital microscope to acquire the image. After that, binarization was performed, and the amount of gaps within the line width was calculated as the gap rate based on the area ratio. For example, a gap rate of 50% means that 50% of the white background area is visible within the line width. The transfer gap was evaluated based on the obtained gap rates according to the following criteria. A: Dropout rate less than 1.0% B: Dropout rate between 1.0% and 5.0% C: Dropout rate between 5.0% and 10.0% D: Dropout rate between 10.0% and 20.0% E: Dropout rate of 20.0% or more

[0162] <Evaluation of image uniformity> Under N / L conditions, the development contrast of the copier was adjusted, and the reflectance density of the output image (FFH) was measured using an optical densitometer and set to 1.50. With this setting, an image pattern with a 40% black monochrome image ratio on the paper surface was output 100,000 times consecutively. Then, three 96H halftone images were output across the entire A3 sheet of paper, and the third image was used for evaluation. Image uniformity was evaluated by measuring the image density at five locations and determining the difference between the maximum and minimum image density values ​​(density difference). Image density was measured using a 500 series spectrophotometer (X-Rite) and judged according to the following criteria. A: Concentration difference is less than 0.03 B: Concentration difference is 0.03 or more and less than 0.06 C: Concentration difference is 0.06 or more and less than 0.09 D: Concentration difference is 0.09 or greater and less than 0.12 E: Concentration difference is 0.12 or greater

[0163] <Static wire stains> After evaluating the above image uniformity, the charging wire contamination of the charger at the black position of the image forming apparatus used for the evaluation was visually checked and evaluated according to the following criteria. A: No contamination was observed. B: A slight amount of contamination was observed. C: Some contamination was observed. D: Contamination was observed. E: Considerable contamination was observed.

[0164] The above evaluation results are shown in Table 5. Those with no item judged as E in each of the above evaluation items were judged as good.

[0165] <Manufacturing Examples of Toner 2 to 20> Except that the types of silica fine particles A and B were changed as shown in Table 3, Toner 2 to 20 were obtained in the same manner as in the manufacturing example of Toner 1.

Table 3

[0166] (Manufacturing Example of Magnetic Carrier 2) Except that the material of the coating resin was changed as follows, Magnetic Carrier 2 was obtained in the same manner as in the manufacturing example of Magnetic Carrier 1. · 26.8 mass% of cyclohexyl methacrylate monomer · 8.6 mass% of methyl methacrylate monomer · 31.3 mass% of toluene · 31.3 mass% of methyl ethyl ketone · 2.0 mass% of azobisisobutyronitrile

[0167] (Manufacturing Example of Magnetic Carrier 3) Except that the material of the coating resin was changed as follows, Magnetic Carrier 3 was obtained in the same manner as in the manufacturing example of Magnetic Carrier 1. · 35.4 mass% of methyl methacrylate monomer · 31.3 mass% of toluene · 31.3 mass% of methyl ethyl ketone · 2.0 mass% of azobisisobutyronitrile

[0168] (Manufacturing Examples of Two-Component Developers 2 to 22) Two-component developers 2 to 22 were obtained in the same manner as the manufacturing example of developer 1, except that the magnetic carrier and toner were changed as shown in Table 4. [Table 4]

[0169] (evaluation) The evaluation was carried out in the same manner as in Example 1, except that two-component developers 2-22 were used. The evaluation results are shown in Table 4. [Table 5]

[0170] This disclosure relates to the following configuration. (Composition 1) A toner having toner particles and silica fine particles A on the surface of the toner particles, The weight-average particle size of the toner is 4.0 to 15.0 μm. The silica microparticles A contain silicone oil, and the carbon reduction rate when the silica microparticles A are washed with hexane is 5-70%. Solid silica fine particles A 29 In CP / MAS measurements of Si-NMR, the Si in the structure represented by the following formula (1) a Peak PD1 corresponds to the silicon atom shown, and Si in the structure represented by the following formula (2). b A peak PD2 corresponding to the silicon atom shown is observed, and the area of ​​peak PD1 is taken as SD1, and the area of ​​peak PD2 is taken as SD2. Solid silica particles after washing with hexane 29 In CP / MAS measurements of Si-NMR, the Si in the structure represented by the following formula (1) a The peak PD1w corresponding to the silicon atom shown and the Si in the structure represented by the following formula (2) b When peak PD2w, which corresponds to the silicon atom shown, is observed, and the area of ​​peak PD1w is taken as SD1w, and the area of ​​peak PD2w is taken as SD2w, SD2 / SD1 is between 0.05 and 0.30. A toner characterized by having an SD2w / SD1w value of 0.05 or higher. [ka] [ka] (In formulas (1) and (2), R independently represents a hydrogen atom, a methyl group, or an ethyl group.) (Configuration 2) The toner according to configuration 1, wherein the carbon reduction rate when the silica fine particles A are washed with hexane is 30-55%. (Composition 3) The toner according to configuration 1 or 2, wherein the components released when the silica fine particles A are washed with hexane include silicone oil. (Composition 4) The toner according to any one of configurations 1 to 3, wherein the amount of carbon-based free components in the silica fine particles A is 3.0 to 9.0 parts by mass per 100 parts by mass of the silica fine particles A. (Composition 5) The BET specific surface area of ​​the aforementioned silica fine particles A is 70 to 160 m². 2 The toner specified in one of the configurations 1-4, which is / g. (Composition 6) The BET specific surface area of ​​the silica fine particles A at a temperature of 30°C and a relative humidity of 80% is 1 m². 2 The amount of water absorbed per unit is 0.01 to 0.07 cm. 3 / m 2 The toner described in one of configurations 1 to 5. (Composition 7) The toner according to any one of configurations 1 to 6, wherein the toner further comprises silica fine particles B that are different from the silica fine particles A. (Composition 8) The toner according to any one of configurations 1 to 7, wherein the content of the silica fine particles A is 0.20 to 3.00 parts by mass per 100 parts by mass of the toner particles. (Composition 9) The toner according to any one of configurations 1 to 8, wherein the silica fine particles A are a silicone oil-treated product of silica fine particles treated with a cyclic siloxane. (Composition 10) A two-component developer having toner and a magnetic carrier, The magnetic carrier comprises magnetic carrier core particles and a resin coating layer on the surface of the magnetic carrier core particles. The resin in the resin coating layer contains monomer units of (meth)acrylic acid ester having alicyclic hydrocarbon groups, A two-component developer wherein the toner is the toner described in any of components 1 to 9. (Composition 11) The two-component developer according to configuration 10, wherein the resin in the resin coating layer further comprises monomer units made of macromonomers represented by the following formula (B). TIFF0007867852000016.tif19170 (In formula (B), A represents a polymer of at least one compound selected from the group consisting of methyl acrylate, methyl methacrylate, butyl acrylate, butyl methacrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, styrene, acrylonitrile, and methacrylonitrile. 6 (This is either H or CH3.) (Composition 12) A method for manufacturing toner to obtain the toner described in any of configurations 1 to 9, A process of mixing silica fine particle substrate and cyclic siloxane, and heat-treating it at a temperature of 300°C or higher to obtain a surface-treated product. A step of obtaining silica fine particles A by further treating the surface-treated material with silicone oil, and A step of mixing the silica fine particles A and toner particles to obtain the toner, A method for manufacturing SATURAL toner. (Composition 13) A method for manufacturing toner according to configuration 12, wherein the temperature at which the surface-treated material is further treated with silicone oil is 300°C or higher.

Claims

1. A toner having toner particles and silica fine particles A on the surface of the toner particles, The weight-average particle size of the toner is 4.0 to 15.0 μm. The silica fine particles A contain silicone oil, and the carbon reduction rate when the silica fine particles A are washed with hexane is 36-48%. Solid silica fine particles A ２９ In Si-NMR CP / MAS measurements, the Si in the structure represented by the following formula (1) ａ Peak PD1 corresponds to the silicon atom shown, and sSi in the structure represented by the following formula (2). ｂ A peak PD2 corresponding to the silicon atom shown is observed, and the area of ​​peak PD1 is defined as SD1, and the area of ​​peak PD2 is defined as SD2. Solid silica particles after washing with hexane ２９ In Si-NMR CP / MAS measurements, the Si in the structure represented by the following formula (1) ａ The peak PD1w corresponding to the silicon atom shown, and the Si in the structure represented by the following formula (2) ｂ When peaks PD2w and PD1w are observed, corresponding to the silicon atoms shown, and the area of ​​peak PD1w is defined as SD1w and the area of ​​peak PD2w is defined as SD2w, SD2 / SD1 is between 0.05 and 0.

30. A toner characterized by having an SD2w / SD1w ratio of 0.05 to 0.

34. (In formulas (1) and (2), R is independently a hydrogen atom, a methyl group, or an ethyl group) (This represents...)

2. The SD2 / SD1 is 0.18 to 0.23, The toner according to claim 1, wherein the SD2w / SD1w is 0.22 to 0.

25.

3. The toner according to claim 1 or 2, wherein the components released when the silica fine particles A are washed with hexane contain silicone oil.

4. The toner according to claim 1 or 2, wherein the amount of carbon-based free components in the silica fine particles A is 3.0 to 9.0 parts by mass per 100 parts by mass of the silica fine particles A.

5. The BET specific surface area of ​​the silica fine particles A is 70 to 160 m². ２ The toner according to claim 1 or 2, wherein the toner is / g.

6. The amount of water adsorbed per 1 m of the BET specific surface area of the silica fine particles A at a temperature of 30°C and a relative humidity of 80% is ２ 0.01 to 0.07 cm ３ / m ２ The toner according to claim 1 or 2, which is such.

7. The toner further comprises silica fine particles B, which are different from the silica fine particles A. The toner according to claim 5, wherein the number-average particle size of the silica fine particles B is 80 to 200 nm.

8. The toner according to claim 1 or 2, wherein the content of the silica fine particles A is 0.20 to 3.00 parts by mass per 100 parts by mass of the toner particles.

9. The toner according to claim 1 or 2, wherein the silica fine particles A are a silicone oil-treated product of silica fine particles treated with a cyclic siloxane.

10. A two-component developer having toner and a magnetic carrier, The magnetic carrier comprises magnetic carrier core particles and a resin coating layer on the surface of the magnetic carrier core particles. The resin in the resin coating layer contains monomer units of (meth)acrylic acid ester having alicyclic hydrocarbon groups, A two-component developer wherein the toner is the toner described in claim 1 or 2.

11. The two-component developer according to claim 10, wherein the resin in the resin coating layer further comprises monomer units represented by the following formula (B). (In formula (B), A represents a polymer of at least one compound selected from the group consisting of methyl acrylate, methyl methacrylate, butyl acrylate, butyl methacrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, styrene, acrylonitrile, and methacrylonitrile. ６ is H or CH ３ (That is the case.)

12. A method for manufacturing toner to obtain the toner described in claim 1 or 2, A process of mixing a silica fine particle substrate with a cyclic siloxane and heat-treating it at a temperature of 330°C or higher to obtain a surface-treated product. A step of obtaining silica fine particles A by further treating the surface-treated material with silicone oil, and A step of mixing the silica fine particles A and toner particles to obtain the toner, A method for manufacturing SATURAL toner.

13. The method for manufacturing toner according to claim 12, wherein the temperature at which the surface-treated material is further treated with silicone oil is 330°C or higher.

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