Two-component developer

Abstract

To provide a toner which prevents generation of toner agglomerate, has stable charging property without depending on a use environment, and has small variation in the charging property even when a large amount of printing is continuously performed.SOLUTION: A toner has toner particles containing a binder resin, and silica fine particles S1, wherein a weight average particle diameter of the toner is 4.0 μm or more and 15.0 μm or less, in the silica fine particles S1, a peak derived from the silica fine particles S1 is observed in 29Si-NMR measurement, in the spectrum obtained by a 29Si-NMR CP / MAS method and a 29Si-NMR DD / MAS method, a peak area of a peak corresponding to a D1 unit structure that the silica fine particles S1 have, a peak area of a peak corresponding to a D2 unit structure that the silica fine particles S1 have, and a peak area of a peak corresponding to a Q unit structure that the silica fine particles S1 have satisfy a predetermined relation.SELECTED DRAWING: None

Description

[Technical Field]

[0001] This disclosure relates to toners and two-component developers for developing electrostatic images used in electrophotography and electrostatic recording methods. [Background technology]

[0002] In recent years, electrophotographic full-color photocopiers have become widespread and are beginning to be applied to the printing market. The printing market is increasingly demanding high speed, high image quality, and high stability. To increase the speed of electrophotographic photocopiers, it is necessary to fix the toner with less heat, and it is important to lower the melt viscosity of the toner due to the heat generated during fixing. Furthermore, for high image quality, the toner needs to have a high charging rate and stable charging properties regardless of the operating environment. In addition, the printing market demands photocopiers with high stability that show little change in image quality or image density even during prolonged continuous use.

[0003] Various studies have been conducted to improve the adhesion of toner by adjusting the melt viscosity of the toner. For example, Patent Document 1 discloses a toner in which the adhesion is improved by lowering the melt viscosity of the toner resin in a certain temperature range. To stabilize the electrostatic properties of toner, external additives are being investigated. For example, Patent Document 2 discloses a toner in which the electrostatic properties are improved by controlling the release rate of silica treated with silicone oil. To achieve high stability with minimal changes in image quality and image density of photocopiers, studies are being conducted to adjust the adhesion state of external additives to the surface of toner particles. For example, Patent Document 3 discloses a toner in which the adhesion to toner particles is improved by adjusting the external additive conditions and strength when silica particles are externally added to the toner particles. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 5-107803 [Patent Document 2] Japanese Patent Publication No. 2004-219609 [Patent Document 3] Japanese Patent Publication No. 2011-215310 [Overview of the Initiative] [Problems that the invention aims to solve]

[0005] To achieve even higher levels of speed, image quality, and stability in photocopiers, toner presents several challenges. When the viscosity of toner is reduced to improve fixation in response to the increased speed of the main unit, the heat resistance of the toner tends to decrease, making it more prone to the formation of toner clumps. If toner clumps are present in the developing unit, when outputting halftone images, uneven shading known as development stains is more likely to occur in the image. Furthermore, if the electrostatic charge of the toner fluctuates depending on the usage environment, it can lead to variations in image density and make it easier for toner to develop on non-image areas, a phenomenon known as fogging. Furthermore, when printing a large number of images with extremely low or high print density in succession, the toner's charge may become unstable, fluctuating excessively high or low, which can cause variations in image density and fogging.

[0006] The toners disclosed in Patent Documents 1 to 3 are insufficient to simultaneously satisfy the requirements for suppressing toner agglomeration, maintaining stable static charge environments, and ensuring stability during continuous high-volume printing; therefore, further improvements are needed.

[0007] This disclosure provides a toner that is less prone to toner agglomeration, has stable electrostatic properties regardless of the usage environment, and maintains high stability even when printing large quantities of toner continuously. Furthermore, it provides a toner that does not produce development stains, has minimal fluctuations in image density regardless of the usage environment or the number of printed pages, and exhibits less fogging. [Means for solving the problem]

[0008] This disclosure is, A toner having toner particles containing a binding resin and silica fine particles S1 on the surface of the toner particles, where the weight average particle diameter of the toner is 4.0 μm or more and 15.0 μm or less, For the silica fine particles S1, 29 in the measurement of Si-NMR, a peak corresponding to the silica fine particles S1 is observed, For the silica fine particles S1, 29 in the spectrum obtained by the Si-NMR·CP / MAS method, there are peaks corresponding to the D1 unit structure, the D2 unit structure, and the Q unit structure of the silica fine particles S1. Let the peak area of the peak corresponding to the D1 unit structure, the peak area of the peak corresponding to the D2 unit structure, and the peak area of the peak corresponding to the Q unit structure be S CP D1, S CP D2, S CP Q, respectively, For the silica fine particles S1, 29 in the spectrum obtained by the Si-NMR·DD / MAS method, there are peaks corresponding to the D1 unit structure, the D2 unit structure, and the Q unit structure of the silica fine particles S1. Let the peak area of the peak corresponding to the D1 unit structure, the peak area of the peak corresponding to the D2 unit structure, and the peak area of the peak corresponding to the Q unit structure be S DD D1, S DD D2, S DD Q. When, the ratio (A / B) of A given by the following formula (1) to B given by the following formula (2) is 4.0 or more and 14.0 or less, A = { (S CP D1 + S CP D2) / S CP Q} × 100 B = { (S DD D1 + S DD D2) / S DD Q} × 100 For the sample obtained by washing the silica fine particles S1 with hexane, 29In the spectrum obtained by Si-NMR·DD / MAS, there are peaks corresponding to the D1 unit structure, the D2 unit structure, and the Q unit structure of the sample, and the peak areas of the peaks corresponding to the D1 unit structure, the D2 unit structure, and the Q unit structure are respectively defined as S DDW D1, S DDW D2, S DDW When Q is the case, This relates to toners where the value of C given by equation (3) below is 1.0 or greater. C={(S DDW D1+S DDW D2) / S DDW Q × 100 [Effects of the Invention]

[0009] According to this disclosure, it is possible to provide a toner that is less prone to toner agglomeration, has stable electrostatic properties regardless of the usage environment, and exhibits small fluctuations in electrostatic properties even when printing a large number of copies continuously. Furthermore, it is possible to provide a toner that suppresses the occurrence of development stains, exhibits small fluctuations in image density regardless of the usage environment and the number of printed pages, and has less fogging. [Brief explanation of the drawing]

[0010] [Figure 1] Schematic diagram of a heat treatment apparatus [Modes for carrying out the invention]

[0011] In this disclosure, unless otherwise specified, the expressions "XX or more and YY or less" or "XX~YY" indicating a numerical range mean a numerical range that includes the lower and upper limits. When specified, the upper and lower limits of each numerical range can be combined in any way.

[0012] Furthermore, a monomer unit refers to the reacted form of monomer substances within a polymer. For example, one carbon-carbon bond in the main chain of a polymer formed by the polymerization of vinyl monomers is considered one unit. A vinyl monomer can be represented by the following formula (Z). [ka] In formula (Z), R Z1 R represents a hydrogen atom or an alkyl group (preferably an alkyl group having 1 to 3 carbon atoms, more preferably a methyl group), Z2 represents any substituent.

[0013] The inventors of this invention conducted research with the aim of obtaining a toner that is less prone to toner agglomeration, has stable electrostatic properties regardless of the usage environment, and does not experience fluctuations in electrostatic properties even when performing large amounts of printing continuously. As a result, they found that by using a toner to which silica fine particles having the configuration of the present disclosure are added externally, an unprecedentedly superior toner can be obtained.

[0014] We believe the reasons for the above effects are as follows: External additives present on the toner surface significantly affect powder properties such as toner aggregation and flow, as well as charge stability. To satisfy these toner performance requirements, it is effective to use hydrophobized silica microparticles as external additives, and it is particularly preferable that the surface is treated with a treatment agent having a siloxane structure, such as silicone oil. Furthermore, we have found that it is important that there are siloxane structures that are strongly attached to the silica microparticles, or chemically bonded to the silica microparticles, so that they cannot be removed even by washing with hexane, and that the molecular mobility of these siloxane structures is within a specific range.

[0015] The siloxane structure present on the surface of silica nanoparticles has the characteristic of being less susceptible to environmental fluctuations in its charge properties. Therefore, when added to toner particles, it strongly enhances the environmental stability of the toner's charge.

[0016] Furthermore, the siloxane structure present on the surface of the silica microparticles contained in the toner has molecular chains that undergo thermal motion, making it easy for them to interact with the binder resin components contained in the toner particles. Therefore, by controlling the molecular mobility of the siloxane molecular chains within an appropriate range, the adhesion between the silica microparticles and the toner particles can be strengthened.

[0017] On the other hand, if the molecular mobility of siloxane molecular chains becomes excessively high, silica microparticles may easily aggregate with each other, or the toner may easily aggregate. As a result, if the toner is left in a high-temperature, high-humidity environment for a long period of time, toner aggregates may form, and when an image is printed, unevenness in density, known as development stains, may occur. In addition, the aggregation of silica microparticles can easily make the toner's charge unstable.

[0018] If the molecular mobility of siloxane molecular chains is too low, aggregation of silica particles and toner is less likely to occur. However, the adhesion between silica particles and toner particles weakens, and when the toner is triboelectrically charged, the silica particles may move across the surface of the toner particles, causing an uneven distribution of silica particles. As a result, the toner's chargeability may become unstable when printing large amounts of material continuously. The molecular mobility of siloxane molecular chains present on the surface of silica nanoparticles S1 used in this disclosure is I think the following:

[0019] 29 In Si-solid-state NMR measurements, there are two measurement methods: DD / MAS and CP / MAS. In this disclosure, we will use these two measurement methods. The following describes each measurement method: 29 SiNMR DD / MAS method, 29 This method is described as Si-NMR·CP / MAS method. First, let's describe the bonding states of silicon atoms. The bonding states of silicon atoms discussed in this disclosure are the D1 unit structure, the D2 unit structure, and the Q unit structure.

[0020] A D1 unit structure is a unit structure in which two oxygen atoms are bonded to a silicon atom, and only one of the oxygen atoms is further bonded to the silicon atom. For example, it is the structure possessed by the silicon atoms within the area enclosed by the square in equation (A) below.

[0021] A D2 unit structure is a unit structure in which two oxygen atoms are bonded to a silicon atom, and both oxygen atoms are further bonded to the silicon atom. For example, it is the structure possessed by the silicon atoms within the area enclosed by the square in equation (B) below. The D unit structure is a combination of the D1 unit structure and the D2 unit structure, in which two oxygen atoms are bonded to a silicon atom, and anything may be bonded to that oxygen atom.

[0022] A Q unit structure is a unit structure in which four oxygen atoms are bonded to a silicon atom, and any other atoms may be bonded to those oxygen atoms. For example, it is the structure of the silicon atom shown in equation (C) below. [ka]

[0023] (R in the formula) 1 , R 2 , R 3 , R 4 , R 5 Each of these independently represents a hydrogen atom or an alkyl group having 1 or 2 carbon atoms. 29 In the Si-NMR·DD / MAS measurement method, all silicon atoms in the sample are observed. Therefore, information about the silicon atom content can be obtained. 29 In the spectrum obtained by Si-NMR·DD / MAS measurement, the peak area corresponding to the D1 unit structure is S DD Let D1 be the unit structure, and S be the peak area corresponding to the D2 unit structure. DD Let D2 be the peak area corresponding to the Q unit structure, and S be the peak area corresponding to the Q unit structure. DDLet Q be the value of D. In this case, the value B calculated by the following formula represents the proportion of D unit structures in the silica nanoparticles. The value of B increases, for example, if the amount of D unit structures contained in the surface treatment agent reacted with the surface of the silica nanoparticle substrate is increased. B={(S DD D1+S DD D2) / S DD Q × 100 B is preferably 5.0 to 15.0, more preferably 6.0 to 12.0, and even more preferably 7.0 to 10.0.

[0024] on the other hand, 29 In Si-NMR·CP / MAS measurements, the measurement is performed while magnetization is carried out via hydrogen atoms present near the silicon atoms, so silicon atoms near hydrogen atoms are observed with high sensitivity. The presence of hydrogen atoms near silicon atoms means that the molecular mobility of the sample being measured is low. In other words, the lower and greater the molecular mobility of the sample being measured, the more sensitively silicon atoms will be observed. 29 The information about D unit structures obtained by Si-NMR·CP / MAS measurements includes not only the quantity of D unit structures but also information about the molecular mobility of D unit structures.

[0025] 29 In the spectrum obtained by Si-NMR·CP / MAS measurement, the peak area corresponding to the D1 unit structure is S CP Let D1 be the unit structure, and S be the peak area corresponding to the D2 unit structure. CP Let D2 be the peak area corresponding to the Q unit structure, and S be the peak area corresponding to the Q unit structure. CP Let Q be the value. In this case, the value A calculated by the following formula represents the content of D unit structures, in which silicon atoms with low molecular mobility are emphasized. The value of A will increase, for example, if a large amount of structures resulting from a surface treatment agent with low molecular mobility are present on the surface of the silica nanoparticle substrate. A={(S CP D1+S CP D2) / S CP Q × 100

[0026] Then, by calculating the ratio (A / B) using A and B described above, information about the molecular mobility derived from the surface-treated D unit structure can be obtained. In other words, a larger A / B value means that the molecular mobility of the D unit structure derived from the surface treatment agent is lower.

[0027] In this disclosure, it is important that the ratio (A / B) is between 4.0 and 14.0. Preferably, A / B is between 6.0 and 14.0, more preferably between 8.0 and 13.0, and even more preferably between 10.0 and 12.0. When silica fine particles S1 that meet this range are added to toner particles, the toner exhibits excellent environmental stability in terms of charge, suppresses the formation of toner aggregates, reduces the occurrence of development stains, and makes it possible to obtain toner with stable charge even when printing large quantities continuously.

[0028] Furthermore, this disclosure relates to a sample obtained by washing silica nanoparticles S1 with hexane. 29 In Si-NMR DD / MAS spectroscopy, the peak area corresponding to the D1 unit structure is S DDW Let D1 be the unit structure, and S be the peak area corresponding to the D2 unit structure. DDW Let D2 be the peak area corresponding to the Q unit structure, and S be the peak area corresponding to the Q unit structure. DDW Let Q be the value. It is important that the value C calculated using the following formula is 1.0 or greater. C={(S DDW D1+S DDW D2) / S DDW Q × 100

[0029] The presence of peaks originating from the D1 and D2 unit structures in the silica fine particles S1 after hexane washing indicates that a certain amount or more of a compound having a siloxane structure is chemically bonded to or very strongly attached to the surface of the silica fine particles S1. C is preferably 3.0 or higher, more preferably 5.0 or higher. There is no particular upper limit, but it is preferably 15.0 or lower, more preferably 12.0 or lower, and even more preferably 10.0 or lower. More preferably, the value is 9.0 or less. By having more siloxane structures chemically bonded or strongly attached to the surface of the silica nanoparticles S1, it becomes easier to achieve stable electrostatic charge.

[0030] Furthermore, the above 29 In the spectrum obtained by the Si-NMR·DD / MAS method, if a peak corresponding to the Q unit structure is observed, it can be determined that "a peak corresponding to silica nanoparticle S1 has been observed."

[0031] The silica microparticles S1 will be washed with hexane using the method described below. When measuring the physical properties of silica microparticles, if it is necessary to separate the silica microparticles from toner particles, the measurements can be taken after separation using the method described later. In the separation method described later, separation is performed in an aqueous medium, so no elution of silicon compounds into the medium occurs, and the silica microparticles can be separated from the toner particles while maintaining the physical properties before the separation process. Therefore, the values ​​of each physical property measured using silica microparticles separated from toner particles will be substantially the same as the values ​​of each physical property measured using silica microparticles before external addition.

[0032] Furthermore, if external additives other than silica microparticles S1 are added to the toner, the silica microparticles S1 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.

[0033] <Hexane washing method for silica microparticles S1> Weigh 1.0 g of silica microparticles into a 50-ml screw tube, and add 20 ml of normal hexane. Then, extract with an ultrasonic homogenizer (VP-050 manufactured by TAITEC Co., Ltd.) at an intensity of 20 (output 10 W) for 10 minutes. Separate the obtained extract with a centrifuge, remove the supernatant, and evaporate the normal hexane from the obtained wet sample using an evaporator to obtain silica particles after hexane washing.

[0034] <NMR Measurement Method> As a pretreatment for NMR measurement, silica microparticles S1 are separated from toner particles by the following method. [Separation Method of Silica Microparticles S1 from Toner Particles] Weigh 20 g of a 10% by mass aqueous solution of "Contaminon N" (a neutral detergent for precision measuring instrument cleaning with pH 7, composed of a nonionic surfactant, an anionic surfactant, and an organic builder) into a 50-mL vial, and mix with 1 g of toner. Set it on the "KM Shaker" (model: V.SX) manufactured by Iwaki Sangyo Co., Ltd., set the speed to 50, and shake for 30 seconds. As a result, the silica microparticles S1 migrate from the surface of the toner particles to the aqueous solution side. After that, in the case of magnetic toner containing a magnetic substance, the silica microparticles S1 that have migrated to the supernatant are separated while restraining the toner particles using a neodymium magnet, and the precipitated toner is dried by vacuum drying (40 °C / 24 hours) to obtain a sample. In the case of non-magnetic toner, the toner particles and the silica microparticles S1 that have migrated to the supernatant are separated with a centrifuge (H-9R; manufactured by Kokusan Co., Ltd.) (at 1000 rpm for 5 minutes). Next, the solid of the silica microparticles recovered from the toner 29 Perform Si-NMR measurement under the measurement conditions shown below. Also, NMR measurement of the silica particles after hexane washing can be performed in the same manner as below.

[0035] 29 [Si-NMR Measurement Method] Solid 29 The measurement conditions for solid Si-NMR are specifically as follows. ​Equipment: JNM-ECA400 (JEOL RESONANCE) Calibration: TMS (tetramethylsilane) to 0 ppm Temperature: room temperature Measurement method: DD / MAS method 29 Si 45° Sample tube: Zirconia 8.0 mmφ Sample: A test tube filled with silica microparticles in powder form. Sample rotation speed: 6kHz Relaxation delay: 90 seconds Scan: 1000

[0036] Also, solid 29 The CP / MAS measurement conditions for Si-NMR (solid state) are as follows: Instrument: JNM-ECA400 (JEOL RESONANCE) Temperature: room temperature Measurement method: CP / MAS method 29 Si 45° Sample tube: Zirconia 8.0 mmφ Sample: A test tube filled with silica microparticles in powder form. Sample rotation speed: 6kHz Relaxation delay: 5 seconds Scan: 10000

[0037] After the above measurement, the solid silica nanoparticles 29 From the Si-NMR spectrum, multiple silane components with different substituents and bonding groups are separated into peaks in M, D, T, and Q units as shown below by curve fitting. Curve fitting is performed using EXcalibur for Windows® version 4.2 (EX series), software for the JNM-EX400 manufactured by JEOL Ltd. The measurement data is loaded by clicking "1D Pro" from the menu icon. Next, "Curve fitting function" is selected from "Command" in the menu bar to perform curve fitting. Curve fitting is performed for each component so that the difference between the composite peak (the sum of the peaks obtained by curve fitting) and the peak in the measurement result (composite peak difference) is minimized. M unit: (R i )(R j )(R k )SiO 1 / 2 Formula (4) D unit: (R g )(R h )Si(O 1 / 2 )2 formula (5) T unit: R m si(O 1 / 2 )3 formula (6) Q unit: Si(O) 1 / 2 )4 formula (7) R in equations (4), (5), and (6) i , R j , R k , R g , R h , R m This refers to alkyl groups such as hydrocarbon groups having 1 to 6 carbon atoms, halogen atoms, hydroxyl groups, acetoxy groups, or alkoxy groups that are bonded to silicon. Furthermore, for the D unit peaks, waveform separation is performed using the Voigt function to calculate the area of ​​the peaks between -19 ppm and -17 ppm corresponding to the D1 unit structure, and the area of ​​the peaks between -23 ppm and -19 ppm corresponding to the D2 unit structure. Additionally, the area of ​​the peaks corresponding to the Q unit structure, ranging from -130 to -85 ppm, is calculated. This calculation is performed on the spectra obtained by the DD / MAS method and the spectra obtained by the CP / MAS method, S CP D1, S CP D2, S CP Q, SDD D1, S DD D2, S DD Calculate Q. Then, calculate A, B, and C.

[0038] The silica nanoparticles S1 are not particularly limited in terms of the treatment agent used to treat the surface of the silica nanoparticle substrate, as long as the requirements for the D unit structure and Q unit structure are met. However, it is preferable to use a treatment agent that contains a siloxane structure. In this disclosure, silica nanoparticles are surface-treated with a surface treatment agent such as silicone oil. In this case, the silica microparticles, including the portion derived from the surface treatment agent, are referred to as silica microparticle substrates. Furthermore, silica microparticles before surface treatment are also called silica microparticle substrates.

[0039] Examples of treatment agents containing siloxane bonds include dimethyl silicone oil, 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, fluorine-modified silicone oil, and silicone oils such as terminally reactive silicone oil, side-chain reactive silicone oil, and terminally side-chain reactive silicone oil.

[0040] Among the treatment agents listed above, it is preferable to use a double-ended reactive silicone oil or a double-ended side-chain reactive silicone oil. These silicone oils are preferable because, since the ends of the silicone oil react with the silanol in the silica nanoparticle substrate, it is possible to perform surface treatment of the silica nanoparticle substrate under relatively mild conditions. This allows for a certain molecular chain length, making it easier to perform surface treatment without reducing mobility too much.

[0041] Preferred treatment agents include known silicone oils such as modified silicone oils in which the methyl groups at the ends and / or on the side chains of the molecular chains of dimethyl silicone oil are substituted with functional groups such as hydrogen atoms, phenyl groups, carbinol groups, hydroxy groups, carboxyl groups, epoxy groups, etc. Among these, due to being substituted with highly reactive functional groups, it is easy to obtain the molecular mobility and reactivity to the silica fine particle substrate required by the present invention. Therefore, at least one functional group selected from the group consisting of a hydroxy group, an epoxy group, and a carbinol group is preferable. Even with other surface treatment agents, silica fine particles S1 may be produced by controlling reaction conditions and the like.

[0042] Preferably, it is a modified silicone oil in which at least the methyl groups at both ends are substituted with functional groups. For example, a preferred modified silicone oil is represented by the following formula (Z).

Chemical formula

[0043] (In formula (Z), R 1 , R 2 are each independently a carbinol group, a hydroxy group, an epoxy group, a carboxy group, or a hydrogen atom, and R 3 is a carbinol group, a hydroxy group, an epoxy group, a carboxy group, an alkyl group (having 1 or 2 carbon atoms, preferably 1 carbon atom), or a hydrogen atom. n and m are average repeating unit numbers, and respectively, n is 1 or more and 200 or less (preferably 1 to 10, more preferably 1 to 5), and m is 1 or more and 200 or less (preferably 10 to 150, more preferably 15 to 100).) R 1 , R 2 are preferably each independently a carbinol group, a hydroxy group, or an epoxy group. R 3 is preferably a carbinol group, a hydroxy group, an epoxy group, or an alkyl group (having 1 or 2 carbon atoms, preferably 1 carbon atom).

[0044] The kinematic viscosity of the modified silicone oil at a temperature of 25°C is not particularly limited, but is preferably 20-100mm 2 / s, more preferably 30-60 mm 2 It is / s. The functional group equivalent of the modified silicone oil is not particularly limited, but is preferably 300 to 2000 g / mol, and more preferably 500 to 1000 g / mol.

[0045] The treatment temperature varies depending on the reactivity of the surface treatment agent used, but is preferably 250°C to 380°C. More preferably 280°C to 350°C, and even more preferably 300°C to 330°C. The treatment time varies depending on the treatment temperature and the reactivity of the surface treatment agent used, but is preferably 5 minutes to 300 minutes, more preferably 30 minutes to 300 minutes, and even more preferably 120 minutes to 300 minutes. The above-mentioned ranges for surface treatment temperature and treatment time are preferable from the viewpoint of allowing the treatment agent to react sufficiently with the silica fine particle substrate.

[0046] The amount of surface treatment agent varies depending on the reactivity of the surface treatment agent used, but preferably it is 0.5 parts by mass to 10 parts by mass, and more preferably 1.0 part by mass to 5.0 parts by mass, per 100 parts by mass of the silica fine particle substrate. By using an amount of surface treatment agent that is sufficient to hydrophobize the silica fine particles without including an excess, the effects of the present invention, such as stable electrostatic properties and reduced development stains, are easily obtained.

[0047] By treating the surface of the silica nanoparticle substrate using the method described above, a D-unit structure is more easily formed on the surface of the silica nanoparticle substrate such that A, B, and C satisfy specific values. Consequently, the silica nanoparticles become hydrophobic. Therefore, by evaluating the amount of moisture adsorbed on the surface of the silica nanoparticle S1, it is possible to obtain an indicator of the extent to which the surface of the silica nanoparticle S1 is coated with a siloxane structure. The amount of moisture adsorbed by silica nanoparticles S1 is determined by the BET specific surface area of ​​1 m² at a temperature of 30°C and a relative humidity of 80%. 2The amount of water adsorbed per unit area is 0.010 cm 3 / m 2 ~0.100 cm 3 / m 2 which is preferable, and more preferably 0.010 cm 3 / m 2 ~0.050 cm 3 / m 2 and even more preferably 0.010 cm 3 / m 2 ~0.040 cm 3 / m 2 and even more preferably 0.010 cm 3 / m 2 ~0.030 cm 3 / m 2 is even more preferred. As a result, a necessary amount of charge can be generated promptly, excessive localization of the generated charge can be avoided, and it can be appropriately diffused around, resulting in better charging stability. Even when the environment changes, the variation in image density is small, and the change in image density during continuous printing can be more effectively suppressed.

[0048] The amount of water adsorbed by the silica fine particles S1 can be increased by reducing the degree of hydrophobic treatment and increasing the remaining amount of silanol groups present on the surface of the silica fine particle substrate. Also, the amount of water adsorbed by the silica fine particles S1 can be decreased by increasing the degree of hydrophobic treatment and reducing the remaining amount of silanol groups present on the surface of the silica fine particle substrate.

[0049] Also, after surface-treating the silica fine particle substrate by the method as described above, further treatment may be performed using a treating agent containing the above-described siloxane bond. The method of performing the treatment is not particularly limited.

[0050] <Method for measuring the amount of water adsorbed> The amount of water adsorbed by the silica fine particles S1 is measured by an adsorption equilibrium measuring device (BELSORP-aqua3 manufactured by BEL Japan, Inc.). This device is for measuring the adsorption amount of the target gas (water vapor).

[0051] (Degassing) Degas any moisture adsorbed on the sample before measurement. Cell, filler rod, cap Attach the device 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 port to be degassed and press the "VAC" button. Degas the cells for at least one day.

[0052] (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 "BEL aqua3.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:

[0053] 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. Determine the amount of water adsorbed at a relative water vapor pressure of 80%.

[0054] <Measurement of BET specific surface area of ​​silica microparticles> The BET specific surface area 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). From the obtained moisture adsorption amount and BET specific surface area, the BET specific surface area of ​​1 m² at a temperature of 30°C and relative humidity of 80% was determined. 2 Calculate the amount of water adsorbed per unit.

[0055] 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.

[0056] The number-average particle size of the silica fine particles S1 is preferably 5.0 nm to 500.0 nm, more preferably 20.0 nm to 300.0 nm, and even more preferably 20.0 nm to 80.0 nm. This particle size range is preferable because it further enhances the stability of the adhesion between the silica fine particles S1 and the toner particles.

[0057] Furthermore, other external additives may be included besides the silica nanoparticles S1. These may include silica nanoparticles other than S1, or inorganic nanoparticles other than silica nanoparticles, or organic nanoparticles such as resin nanoparticles. When used in combination, it is preferable that SS2 / SS1 is 1.2 or greater, where SS1 is the number-average particle size of the silica nanoparticles S1 and SS2 is the number-average particle size of the external additive used in combination. In this case, the embedding of the silica nanoparticles S1 is suppressed even during long-term use or use in high-temperature environments, making it possible to further stabilize the electrostatic properties regardless of the usage environment.

[0058] <Number-average particle size of silica microparticles S1> The number-average particle size of silica microparticles S1 and S2 can be measured using a Microtrac particle size distribution analyzer HRA(X-100) (manufactured by Nikkiso Co., Ltd.) with a range setting of 0.001 μm to 10 μm.

[0059] <Binding resin for toner particles> Toner particles contain a binder resin. Known binder resins can be used for 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.

[0060] 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 constituting polyester resins include the following dicarboxylic acids or their derivatives: benzenedicarboxylic acids such as phthalic acid, terephthalic acid, isophthalic acid, and phthalic anhydride, or their anhydrides or lower alkyl esters; alkyldicarboxylic 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 their anhydrides or lower alkyl esters; and 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.

[0061] Examples of divalent alcohol components that make up polyester resin include the following: 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]

[0062] 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]

[0063] 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.

[0064] In addition to the divalent carboxylic acid and divalent alcohol components mentioned above, the polyester resin may also contain trivalent or higher carboxylic acid components and trivalent or higher alcohol components as constituent 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.

[0065] 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, and behenic acid. Other examples include 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.

[0066] The toner can be used as either a magnetic one-component toner, a non-magnetic one-component toner, or a non-magnetic two-component toner. 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 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.

[0067] Examples of colorants used when used as non-magnetic one-component toners and non-magnetic two-component toners 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.

[0068] Suitable colorants for the yellow color include pigments or dyes. Examples 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, 162, etc. These can be used individually or in combination of two or more.

[0069] 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.

[0070] 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 some or all of the fatty acid esters have been deoxidized, such as deoxidized carnauba wax.

[0071] 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; methylenebisstearate amide, ethylenebiscaprate amide, and ethylenebislaurin Examples include saturated fatty acid bisamides such as acid amides and hexamethylenebisstearamide; unsaturated fatty acid amides such as ethylenebisoleamide, hexamethylenebisoleamide, N,N'-dioleyladipamide, and N,N'-dioleylsebacamide; aromatic bisamides such as m-xylenebisstearamide and N,N'-distearylisophthalamide; 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 using 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.

[0072] Waxes that are particularly preferred are aliphatic hydrocarbon waxes. For example, low molecular weight hydrocarbons obtained by radical polymerization of alkylenes under high pressure or by 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.

[0073] Furthermore, it is more preferable to use paraffin waxes that have been separated by methods such as press efflorescence, solvent method, vacuum distillation, or fractional crystallization. In particular, among the 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.

[0074] 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. The charge-controlling agent is preferably added in an amount of 0.1 parts by mass to 10 parts by mass per 100 parts by mass of the binder resin.

[0075] Toner and magnetic carrier may be mixed and used as a two-component developer. A magnetic carrier consists of magnetic carrier core particles and a resin coating layer that covers (coats) the surface of the magnetic carrier core particles. The resin coating layer does not necessarily need to cover the entire surface of the magnetic carrier core particles; there may be areas where the magnetic carrier core particles are partially exposed. As magnetic carrier core particles, ordinary magnetic carrier core particles such as ferrite and magnetite, or resin-coated carriers can be used. In addition, magnetic material-dispersed resin particles in which magnetic material powder is dispersed in a resin component, or porous magnetic core particles containing resin in the voids can be used.

[0076] Magnetic material components used in magnetic material-dispersed resin particles include 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; and magnetoplanar containing barium, strontium, or barium-strontium. Various magnetic iron compound particle powders can be used, such as spinel-type ferrite particle powder containing at least one selected from manganese, nickel, zinc, lithium, and magnesium.

[0077] 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.

[0078] 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.

[0079] The magnetic carrier core particles are preferably porous magnetic core particles containing resin in the 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.

[0080] The magnetic carrier comprises magnetic carrier core particles and a resin coating layer that covers (coats) the surface of the magnetic carrier core particles. 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.

[0081] Examples of resins used in the resin coating layer include acrylic resins such as acrylic acid ester copolymers and methacrylic acid ester copolymers, styrene-acrylic resins such as styrene-acrylic acid ester copolymers and styrene-methacrylic acid ester copolymers, fluorine-containing resins such as polytetrafluoroethylene, tetrafluoroethylene-hexafluoropropylene copolymer, monochlorotrifluoroethylene polymer, and polyvinylidene fluoride, 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.

[0082] Among these, copolymers synthesized using (meth)acrylic acid ester monomers having alicyclic hydrocarbon groups are particularly preferred from the viewpoint of electrostatic stability. The resin preferably contains monomer units made of (meth)acrylic acid esters having alicyclic hydrocarbon groups. Examples of (meth)acrylic acid esters having an alicyclic hydrocarbon group include 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.

[0083] Furthermore, the content (mass-based copolymerization ratio) of monomer units consisting of methacrylic acid ester having alicyclic hydrocarbon groups in the copolymer used in the resin coating layer is preferably 5.0% by mass or more and 80.0% by mass or less. Within this range, good electrostatic properties are obtained in high-temperature and high-humidity environments.

[0084] 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 localized peeling of the resin coating layer. Mac The macromonomer is preferably a macromonomer having a polymer portion of at least one monomer selected from the group consisting of methyl acrylate, methyl methacrylate, butyl acrylate, butyl methacrylate, 2-ethylhexyl acrylate, and 2-ethylhexyl methacrylate. 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 the macromonomer shown in formula (B) below. [ka]

[0085] 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. 3 It is either H or CH3. A is preferably a polymer of methyl methacrylate.

[0086] To improve the adhesion between the magnetic carrier core particles and the resin coating layer, the weight-average molecular weight of the macromonomer is preferably 3,000 to 10,000, and more preferably 4,000 to 7,000.

[0087] In order to improve the adhesion between the magnetic carrier core particles and the resin coating layer, it is preferable that the content ratio of monomer units by macromonomers in the resin used in the resin coating layer (copolymerization ratio based on the mass of macromonomers) be 0.5% by mass or more and 30.0% by mass or less.

[0088] <Measurement of weight-average molecular weight of macromonomers> The weight-average molecular weight was determined using gel permeation chromatography (GPC) as follows: Measure using the following procedure. 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

[0089] 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).

[0090] The toner comprises toner particles and silica fine particles S1 on the surface of the toner particles. In other words, the toner contains silica fine particles S1 as an external additive. The amount of silica fine particles S1 added to the toner particles is preferably 0.01 parts by mass to 10.00 parts by mass per 100 parts by mass of toner particles, more preferably 1.0 part by mass to 10.00 parts by mass. Even more preferably, it is 1.0 part by mass to 5.00 parts by mass. This allows the silica fine particles to properly coat the toner particles, resulting in a more effective manifestation of the present invention, improved electrostatic stability, smaller fluctuations in image density even when the environment changes, and suppression of changes in image density during continuous printing.

[0091] The addition of external additives such as silica microparticles to toner particles can be performed by mixing the toner particles and the external additive 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.); and Redigge mixer (manufactured by Matsubo Co., Ltd.).

[0092] It is preferable that the toner particles are surface-treated with hot air. Furthermore, it is preferable to apply the hot air surface treatment to the toner particle surface with silica fine particles S1 attached before the hot air treatment. This is preferable because it prevents the silica fine particles S1 from moving across the toner particle surface even during long-term use, thus stabilizing the electrostatic charge.

[0093] For example, the toner manufacturing method is: Process for obtaining toner particles, The process of preparing silica nanoparticles S1, A step in which a portion of the silica fine particles S1 are added and mixed to the obtained toner particles. A process of heat-treating toner particles to which silica fine particles have been added externally, and Preferably, the process involves adding the remaining silica fine particles S1 to the heat-treated toner particles to obtain toner. In the external addition process before heat treatment, it is preferable to add 65 to 85% by mass of silica fine particles S1. In the external addition mixing to the heat-treated toner particles, it is preferable to add 15 to 35% by mass of silica fine particles S1.

[0094] The following provides a specific example of a method for surface-treating toner particles (for example, toner particles mixed with externally added silica fine particles) using hot air, employing the heat treatment apparatus shown in Figure 1. In this example, toner particles will be referred to as the workpiece.

[0095] The material to be processed, supplied in a fixed quantity by the raw material quantitative supply means 1, is guided by compressed gas adjusted by the compressed gas flow rate adjustment means 2 into an introduction pipe 3 installed vertically to the raw material supply means. The material to be processed, having passed through the introduction pipe 3, is uniformly dispersed by a conical projection member 4 located in the center of the raw material supply means, and is guided into eight radially spreading supply pipes 5 to a processing chamber 6 where heat treatment takes place.

[0096] At this time, the material to be processed supplied to the processing chamber 6 has its flow restricted by a restricting means 9 provided within the processing chamber 6 to regulate the flow of the material to be processed. As a result, the material to be processed supplied to the processing chamber 6 is heat-treated while swirling around inside the processing chamber 6, and then cooled. The hot air used to heat-treat the supplied material is supplied from the hot air supply means 7, distributed by the distribution member 12, and introduced into the processing chamber 6 in a spiral motion by the swirling member 13 for swirling the hot air. The swirling member 13 for swirling the hot air has multiple blades, and the swirling of the hot air can be controlled by the number and angle of these blades (note that 11 indicates the outlet of the hot air supply means).

[0097] The hot air supplied into the processing chamber 6 preferably has a temperature of 100°C to 300°C at the outlet of the hot air supply means 7, and more preferably 130°C to 190°C. If the temperature at the outlet of the hot air supply means 7 is within the above range, the embedding of silica fine particles can be controlled while preventing fusion or coalescence due to overheating of the workpiece. The hot air is supplied from the hot air supply means 7. Furthermore, the heat-treated resin particles are cooled by cold air supplied from the cold air supply means 8. The temperature of the cold air supplied from the cold air supply means 8 is preferably between -20°C and 30°C. If the temperature of the cold air is within the above range, the heat-treated workpiece can be cooled efficiently, and fusion or coalescence of the workpiece is less likely to occur. Also, the absolute moisture content of the cold air is 0.5 g / m³. 3 More than 15.0g / m 3 The following is preferable:

[0098] Next, the cooled material to be processed is collected by a collection means 10 located at the lower end of the processing chamber 6. A blower (not shown) is provided at the end of the collection means 10, which is used to suction and transport the material.

[0099] Furthermore, the powder particle supply port 14 is positioned so that the direction of rotation of the supplied material to be processed and the direction of rotation of the hot air are the same, and the recovery means 10 is also positioned tangentially on the outer periphery of the processing chamber 6 to maintain the rotation direction of the rotated material to be processed. In addition, the cold air supplied from the cold air supply means 8 is configured to be supplied horizontally and tangentially from the outer periphery of the device to the circumferential surface of the processing chamber. The swirling direction of the material to be processed supplied from the powder particle supply port 14, the swirling direction of the cold air supplied from the cold air supply means 8, and the swirling direction of the hot air supplied from the hot air supply means 7 are all in the same direction. Therefore, turbulence does not occur in the processing chamber, the swirling flow within the apparatus is strengthened, and a strong centrifugal force is applied to the material to be processed before heat treatment, further improving dispersibility, resulting in toner particles with fewer coalescing particles. It is easy to obtain.

[0100] 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.

[0101] 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. During this process, the embedding of silica particles on the surface of the toner particles can be controlled by adjusting the exhaust temperature during fine grinding. The toner particles and silica additive are then mixed using a mixer such as a Henschel mixer to obtain the toner.

[0102] 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.).

[0103] 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).

[0104] 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.).

[0105] Furthermore, if necessary, after grinding, the surface treatment of the toner particles can be performed 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.) to control the embedding of silica microparticles on the surface of the toner particles.

[0106] 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.).

[0107] Examples of sieving devices used to separate coarse particles include the following: Ultrasonic (manufactured by Koei Sangyo Co., Ltd.); Resona sieve, gyro shifter (manufactured by Tokuju Kogyo Co., Ltd.); Vibrasonic system (manufactured by Dalton Co., Ltd.); Soniclean (manufactured by Shinto Kogyo Co., Ltd.); Turbo screener (manufactured by Turbo Kogyo Co., Ltd.); Micro shifter (manufactured by Makino Sangyo Co., Ltd.); circular vibrating screen.

[0108] Toner particles produced by the emulsification and agglutination method are manufactured, for example, as follows: <Process for preparing a resin fine particle dispersion (preparation process)> For example, polyester resin or styrene-acrylic resin 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.

[0109] 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.

[0110] 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.

[0111] 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.

[0112] Examples of basic compounds include inorganic bases such as sodium hydroxide and potassium hydroxide, and organic bases such as triethylamine, trimethylamine, dimethylaminoethanol, and diethylaminoethanol. Basic compounds may be used individually or in combination of two or more.

[0113] <Agglomeration process> The aggregation process involves, for example, mixing a 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.

[0114] Suitable methods for forming aggregate particles include adding and mixing a coagulant into a mixed liquid, and then increasing the temperature or applying mechanical power as appropriate.

[0115] A dispersion of colorant microparticles is prepared by dispersing a colorant. The colorant microparticles are dispersed by known methods, but media-type dispersers such as rotary shear homogenizers, ball mills, sand mills, and attritors, as well as high-pressure opposing impact dispersers, are preferably used. Furthermore, surfactants or polymeric dispersants can be added as needed to provide dispersion stability.

[0116] 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.

[0117] 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.

[0118] The addition and mixing of the flocculant is preferably carried out within a temperature range of room temperature to 75°C. Mixing under these temperature conditions allows for stable flocculation. Mixing can be carried out using known mixing equipment, homogenizers, mixers, etc.

[0119] <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.

[0120] 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.

[0121] <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.

[0122] <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.

[0123] <Drying and Classification Process> Toner particles can be obtained by drying the washed resin particles and classifying them as appropriate.

[0124] <Process for adding external additives to toner particles> The toner particles and external additives can be mixed using a mixer such as a Henschel mixer to obtain toner.

[0125] 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 the resin composition particles, and then the organic solvent contained in the resin composition particles is removed to produce toner particles. The dissolution suspension method can be applied to any resin component that dissolves in an organic solvent. In addition, shape control is easily achieved by adjusting the conditions during solvent removal. The following describes, but is not limited to, a toner manufacturing method using the dissolution suspension method.

[0126] <Resin component dissolution process> In the resin component dissolution step, the binder resin, and optionally other components such as colorants, waxes, and silicone oils, are dissolved or dispersed in an organic solvent to prepare the resin composition. 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.

[0127] 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.

[0128] 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.

[0129] <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, the aqueous medium preferably contains 1% to 30% by mass of a monovalent metal salt. The inclusion 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 better blocking resistance and a better particle size distribution.

[0130] 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.

[0131] The 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.

[0132] 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.

[0133] <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.

[0134] <Washing, drying, and classification process> After the solvent removal process, a washing and drying process may be performed in which the toner particles are washed multiple times with water, 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.

[0135] <Process for adding external additives to toner particles> The toner particles and external additives can be mixed using a mixer such as a Henschel mixer to obtain toner.

[0136] Toner particles produced by suspension polymerization are manufactured, for example, as follows: A polymerizable monomer composition is prepared by uniformly dissolving or dispersing polymerizable monomers, colorants, wax components, and polymerization initiators using a disperser such as a homogenizer, ball mill, or ultrasonic disperser. After granulating the polymerizable monomer composition by dispersing it in an aqueous medium, toner particles are obtained by polymerizing the polymerizable monomers in the particles made of the polymerizable monomer composition.

[0137] 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.

[0138] Toner particles are obtained by filtering, washing, drying, and classifying the polymerized particles using known methods. The obtained toner particles and external additives can be mixed using a mixer such as a Henschel mixer to obtain toner.

[0139] The weight-average particle size (D4) of the toner is 4.0 μm or more and 15.0 μm or less. Preferably, it is 4.0 μm or more and 9.0 μm or less. This allows the silica fine particles S1 to properly coat the toner particles, and optimizes the contact area between the silica fine particles S1 and the toner particles, resulting in a more effective manifestation of the present invention, improved electrostatic stability, smaller fluctuations in image density even when the environment changes, and suppression of changes in image density during continuous printing.

[0140] <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 Multisizer, a precision particle size distribution analyzer with a pore electrical resistance method equipped with a 100 μm aperture tube. Using the "Beckman Coulter Multisizer 3" (registered trademark, manufactured by Beckman Coulter) and the accompanying dedicated software "Beckman Coulter Multisizer 3 Version 3.51" (manufactured by Beckman Coulter) for setting measurement conditions and analyzing measurement data, measurements were taken with an effective measurement number of 25,000 channels, and the measurement data was 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 to 60 μm.

[0141] 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 about 30 ml of the electrolytic aqueous solution into a 100 ml flat-bottomed glass beaker, and add about 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]

[0142] The basic structure and features of the present invention have been described above. The present invention will now be described in detail based on examples. However, the present invention is not limited thereto. Unless otherwise specified, parts and percentages are based on mass.

[0143] <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 inlet pipe, thermometer, and stirring device are attached to it. A condensation polymerization reaction was carried out at 230°C while introducing N2 gas into a composting chamber. The reaction time was adjusted to achieve the desired softening point. After the reaction was complete, 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:

[0144] [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), and is performed according to the manual included with the device. In this device, a constant load is applied from above the sample by a piston, the sample filled in the cylinder is heated and melted, and the molten sample is pushed out 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. In this disclosure, 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:

[0145] 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

[0146] <Example of manufacturing silica microparticle S1-1> 1 kg of fumed silica (silica microparticle substrate; spherical) with a number-average particle size of 40 nm was placed in a reaction vessel and heated while stirring under a nitrogen atmosphere, with the temperature inside the vessel controlled to 300°C. Next, a reactive silicone oil with epoxy type epoxy at both end chains (chemical formula (1) below, kinematic viscosity at 25°C: 45 mm) was added. 2 Silica nanoparticles S1-1 were obtained by supplying (600 g / mol, equivalent to 600 g / mol) to the reaction vessel and treating it in this state for 240 minutes. The physical properties of the obtained silica nanoparticles are shown in Table 1. [ka] In chemical formula (1), m and n are positive integers, where m is approximately 3¹ and n is approximately 3.

[0147] <Production of silica fine particles S1-2 to S1-17> For the fumed silica (silica fine particle substrate; spherical) with the number average particle diameter as shown in Table 1, the production was carried out in the same manner as silica fine particles S1-1, except that the treating agent and treating conditions were changed as shown in Table 1. The treating agents shown in Table 1 are as follows. Both-terminal alcohol type reactive silicone oil (the following chemical formula (2), kinematic viscosity at 25 °C; 40 mm 2 / s, functional group equivalent; 1000 g / mol)

Chem.

[0148] Both-terminal side-chain alcohol type reactive silicone oil (the following chemical formula (3), kinematic viscosity at 25 °C; 55 mm 2 / s, functional group equivalent; 1500 g / mol)

Chem.

[0149] Both-terminal side-chain carbinol type reactive silicone oil (the following chemical formula (4), kinematic viscosity at 25 °C; 42 mm 2 / s, functional group equivalent; 750 g / mol)

Chem.

[0150] <Production of silica fine particles S1-18> 500g of fumed silica (silica microparticle substrate) with a number-average particle size of 40nm was placed in a reaction vessel, and the temperature inside the reaction vessel was controlled to 300°C under nitrogen purging and stirring. Next, polydimethylsiloxane (kinematic viscosity at 25°C: 50mm) was added as a surface treatment agent. 2 A solution of 50g of silica (average repeating units n=60) diluted with 500g of hexane was supplied by spraying, and the silica nanoparticle substrate was surface-treated by heating and stirring for 60 minutes to obtain silica nanoparticles S1-18.

[0151] <Manufacturing examples of silica microparticles S1-19 and S1-20> Except for the surface treatment agent and treatment conditions shown in Table 1, the silica fine particles were manufactured in the same manner as those used for S1-18.

[0152] [Table 1]

[0153] <Toner manufacturing example 1> • Binding resin 1,100 units • Hydrocarbon wax (melting point 78°C) 4 parts CI Pigment Blue 15:3 4 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.

[0154] Next, silica fine particles were added to the obtained toner particles 1 as the first external additive treatment, as shown below. • Toner particle ratio: 1:100 parts • Silica microparticles S1-1: 2.0 parts The above ingredients were mixed in a Henschel mixer. The Henschel mixer was operated at a rotation speed of 4000 rpm, a rotation time of 2 minutes, and a heating temperature of room temperature. Subsequently, heat treatment was performed using the surface heat treatment apparatus shown in Figure 1, embedding some of the silica nanoparticles into the surface of the toner particles. The operating conditions of the surface heat treatment apparatus were a feed rate of 1.0 kg / hr, a hot air temperature of 180°C, and a hot air flow rate of 1.4 m³. 3 / min, cold air temperature=3℃, cold air flow rate=1.2m 3 I set it to / min.

[0155] Next, using a wind classifier utilizing the Coanda effect ("Elbow Jet Lab EJ-L3," manufactured by Nippon Steel Mining Co., Ltd.), fine and coarse powders were simultaneously classified and removed toner particles in which silica fine particles S1-1 were embedded on the surface. The heat-treated toner particles thus obtained were then subjected to a second external additive treatment with silica fine particles, as described below. • Toner particles with silica microparticles S1-1 embedded on the surface: 1 / 100 units • Silica microparticles S1-1: 0.6 parts 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. The surface treatment conditions for toner 1 are shown in Table 2.

[0156] <Toner manufacturing examples 2-22> Except for changing the type of silica microparticles, the amount added, and the processing conditions as shown in Table 2, the toner was manufactured in the same manner as in Manufacturing Example 1.

[0157] [Table 2]

[0158] <Example of manufacturing magnetic carrier core particle 1> [Process 1 (Weighing and Mixing Process)] Fe2O368.3% by mass MnCO328.5% by mass 2.0 mass% of Mg(OH)2 1.2 mass% of SrCO3 Weighed the above ferrite raw materials, added 20 parts of water to 80 parts of the ferrite raw materials, and then wet-mixed them for 3 hours with a ball mill using zirconia with a diameter of 10 mm to prepare a slurry. The solid content concentration of the slurry was set to 80 mass%.

[0159] [Process 2 (Calcination Process)] After drying the mixed slurry with a spray dryer (manufactured by Okawara Chemical Machinery Co., Ltd.), it was fired in a batch-type electric furnace at a temperature of 1050 °C for 3.0 hours in a nitrogen atmosphere (oxygen concentration: 1.0 vol%) to produce a calcined ferrite.

[0160] [Process 3 (Grinding Process)] The calcined ferrite was ground to about 0.5 mm with a crusher, then water was added to prepare a slurry. The solid content concentration of the slurry was set to 70 mass%. It was ground for 3 hours with a wet ball mill using 1 / 8-inch stainless steel beads to obtain a slurry. Further, this slurry was ground for 4 hours with a wet bead mill using zirconia with a diameter of 1 mm to obtain a calcined ferrite slurry with a volume-based 50% particle diameter (D50) of 1.3 μm.

[0161] [Process 4 (Granulation Process)] To 100 parts of the above calcined ferrite slurry, 1.0 part of ammonium polycarboxylate as a dispersant and 1.5 parts of polyvinyl alcohol as a binder were added, and then granulated and dried into spherical particles with a spray dryer (manufactured by Okawara Chemical Machinery Co., Ltd.). After performing particle size adjustment on the obtained granulated product, it was heated at 700 °C for 2 hours using a rotary electric furnace to remove organic substances such as the dispersant and the binder.

[0162] [Process 5 (Firing Process)] In a nitrogen atmosphere (oxygen concentration: 1.0 vol%), the time from room temperature to the firing temperature (1100 °C) was set to 2 hours, and the granulated product was held at a temperature of 1100 °C for 4 hours and fired. Then, the temperature was lowered to 60 °C over 8 hours, the atmosphere was returned from nitrogen to air, and the fired product was taken out at a temperature of 40 °C or lower.

[0163] [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.

[0164] [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.

[0165] 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 (UD-AT drum mixer manufactured by Sugiyama Heavy Industries Co., Ltd.) in a rotatable mixing container, and the temperature was raised to 140°C at a heating rate of 2°C / min under a nitrogen atmosphere while stirring. Heating and stirring were then continued at 140°C for 50 minutes. After cooling to room temperature, the resin-filled and hardened ferrite particles are removed and then magnetically separated. Non-magnetic materials were removed using a machine. Furthermore, coarse particles were removed using a vibrating screen to obtain magnetic carrier core particles 1 filled with resin.

[0166] [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 obtained resin were dissolved in a mixed solvent of 40 parts of toluene and 30 parts of methyl ethyl ketone to obtain a resin solution (solid content concentration 30%).

[0167] [Preparation of coating resin solution] • Resin solution (solid content concentration 30%) 33.3% by mass • Toluene 66.4% by mass • Carbon black (Regal 330; manufactured by Cabot) 0.3% by mass (number average particle size of primary particles: 25 nm, nitrogen adsorption specific surface area: 94 m²) 2 / g, DBP oil absorption: 75ml / 100g) The above materials were placed in a paint shaker and dispersed for 1 hour using zirconia beads with a diameter of 0.5 mm. The resulting dispersion was filtered through a 5.0 μm membrane filter to obtain a coating resin solution.

[0168] <Example of manufacturing magnetic carrier 1> The coating resin solution and magnetic carrier core particles 1 were added to a vacuum-degassed kneader maintained at room temperature (the amount of coating resin solution added was 2.5 parts of resin component for every 100 parts of magnetic carrier core particles 1). After adding the solvent, the mixture was stirred at a rotation speed of 30 rpm for 15 minutes. Once a certain amount (80%) of the solvent had evaporated, the temperature was raised to 80°C while mixing under reduced pressure. Toluene was then removed by distillation over 2 hours, followed by cooling. The obtained magnetic carriers were separated for low magnetic force by magnetic separation, passed through a sieve with an opening of 70 μm, and then classified using an air classifier to obtain magnetic carrier 1 with a 50% particle size (D50) of 38.2 μm based on volume distribution.

[0169] <Example of manufacturing magnetic carrier 2> Magnetic carrier 2 was obtained in the same manner as in the manufacturing example of magnetic carrier 1, except that the material of the coating resin was changed as described below. • Cyclohexyl methacrylate monomer 26.8% by mass • Methyl methacrylate monomer 8.6% by mass • Toluene 31.3% by mass • Methyl ethyl ketone 31.3% by mass • Azobisisobutyronitrile 2.0% by mass

[0170] <Manufacturing example of magnetic carrier 3> Magnetic carrier 3 was obtained in the same manner as in the manufacturing example of magnetic carrier 1, except that the material of the coating resin was changed as described below. • Methyl methacrylate monomer 35.4% by mass • Toluene 31.3% by mass • Methyl ethyl ketone 31.3% by mass • Azobisisobutyronitrile 2.0% by mass

[0171] <Preparation of two-component developer> Using the combinations of toners 1-22 and magnetic carriers 1-3 listed in Table 3, mix the toners in a V-type mixer (V-10 model: Tokuju Seisakusho Co., Ltd.) for 0.5 seconds to achieve a toner density of 8.0% by mass. -1 Two-component developers 1 to 24 were prepared by mixing under conditions of a rotation time of 5 minutes.

[0172] [Table 3]

[0173] <Examples 1-21, Comparative Examples 1-3> The following evaluations were performed using the obtained two-component developers 1 to 24. The evaluation results are shown in Table 4. Note that two-component developers 6-21 were evaluated as reference examples. <Rating> The image forming machine used was an imagePRESS C850 (manufactured by Canon). The fixing unit was removed externally to allow arbitrary control of the fixing temperature, and the image forming speed was modified to produce 105 A4 size images per minute. In addition, the development contrast was made adjustable to an arbitrary value, and the automatic correction function of the main unit was disabled. Furthermore, the frequency of the alternating electric field was fixed at 2.0 kHz, and the voltage between peaks (Vpp) was made adjustable in 0.1 kV increments from 0.7 kV to 1.8 kV. A two-component developer was placed in the cyan position of the image forming apparatus, the charging voltage VD of the electrostatic latent image carrier and the laser power were adjusted, and the evaluation described below was performed. Furthermore, evaluations of temporal stability and developability before and after continuous printing were conducted at two levels: an image forming speed of 105 sheets / min for A4 size and an image forming speed of 85 sheets / min for A4 size. The evaluation paper used is white paper (product name: CS-814 (A4, 81.4 g / m²)). 2 (Canon Marketing Japan Inc.) was used.

[0174] <Evaluation of the long-term stability of printed images> Under normal temperature and humidity conditions (temperature 23°C, humidity 50 RH%, hereinafter also referred to as "N / N environment"), the development contrast of the copier body was adjusted, and the reflectance density of the output image was measured using an optical densitometer, setting it to 1.48 to 1.52. Five images were output under the above image formation conditions, the density of the output images was measured, the average was calculated, and image density A was determined. Next, in a high-temperature, high-humidity environment (temperature 30°C / humidity 80RH%, hereinafter also referred to as the "H / H environment"), the copier was left in the H / H environment for 24 hours with the development contrast set to N / N. Five images were printed, the average was calculated, and image density B was determined. An X-Rite color reflectance densitometer (manufactured by X-Rite) was used as the optical densitometer. Then, the density fluctuation difference shown in the following formula was calculated to evaluate the image density stability. Images with a density fluctuation difference of less than 0.14 were judged to be good. Density variation difference = |Image density A - Image density B| [Evaluation Criteria] A: Less than 0.06 B: 0.06 or higher, 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

[0175] <Evaluation of developability before and after continuous printing> Under N / L conditions, the initial Vpp was fixed at 1.3kV, and the contrast potential was set so that the reflectance density of a solid cyan image was 1.50. With these settings, 2000 image patterns with a cyan monochrome image ratio of 1% to the paper surface were output consecutively. Then, with Vpp set to 1.3kV, a solid cyan monochrome image was output again, and the reflectance density was measured. The contrast potential at which the reflectance density of the solid cyan monochrome image reached 1.50 was determined, and the difference from the initial value was compared. Reflectance density was measured using a 500 series spectrophotometer (X-Rite). Results of D rank or higher were considered good. [Evaluation Criteria] AAA: Difference from initial voltage is less than 30V. AA: The difference from the initial value is between 30V and 35V. A: The difference from the initial value is between 35V and 40V. B: The difference from the initial value is between 40V and 60V. C: The difference from the initial value is between 60V and 80V. D: The difference from the initial value is between 80V and less than 100V. E: The difference from the initial value is 100V or more.

[0176] <Evaluation of developing stains (toner aggregation)> A two-component developer was left in a high-temperature, high-humidity environment (30°C / 95%Rh) for 3 months. Subsequently, under normal temperature and humidity conditions (23°C / 50%Rh), 300 full-surface halftone images were printed, and the number of toner aggregate stains per A4 halftone print image was evaluated. The image output settings were configured to produce a paper reflectance density of 0.80 in halftone. The reflectance density was measured using a 500 series spectrophotometer (manufactured by X-Rite). [Evaluation Criteria] A: Less than 0.01 B: 0.01 or more, less than 0.1 C: 0.1 or more, less than 0.5 D: 0.5 or more, less than 3.0 E: 3.0 or more

[0177] <Cover concentration> The fogging concentration was measured as follows: Under H / H conditions, plain color copier / printer paper GF-C157 (A4, 157 g / cm²) was used. 2 Immediately after printing the 20,000th image using the (sold by Canon Marketing Japan Inc.) printer, a solid white sheet was passed through. Then, using the "REFLECTMETER MODEL TC-6DS" (manufactured by Tokyo Denshoku Co., Ltd.), the color cast density (%) was calculated from the difference between the whiteness of the white areas of the measured image and the whiteness of the transfer paper. An amber filter was used. A smaller value indicates a better color cast level. [Evaluation Criteria] A: Cover concentration less than 0.5% B: Coverage concentration 0.5% or more and less than 1.0% C: Coverage concentration 1.0% or more and less than 2.0% D: Coverage concentration of 2.0% or higher

[0178] [Table 4]

[0179] Furthermore, this disclosure relates to the following configuration. (Composition 1) A toner having toner particles containing a binder resin and silica fine particles S1 on the surface of the toner particles, The weight-average particle size of the toner is 4.0 μm or more and 15.0 μm or less. The silica fine particles S1 29 In Si-NMR measurements, a peak corresponding to the silica nanoparticle S1 was observed. 29In the spectrum obtained by Si-NMR·CP / MAS, there are peaks corresponding to the D1 unit structure of the silica nanoparticle S1, peaks corresponding to the D2 unit structure of the silica nanoparticle S1, and peaks corresponding to the Q unit structure of the silica nanoparticle S1. The peak areas of the peaks corresponding to the D1 unit structure, the peak areas of the peaks corresponding to the D2 unit structure, and the peak areas of the peaks corresponding to the Q unit structure are respectively S CP D1, S CP D2, S CP Let Q be the case. 29 In the spectrum obtained by Si-NMR·DD / MAS method, there are peaks corresponding to the D1 unit structure of the silica nanoparticle S1, peaks corresponding to the D2 unit structure of the silica nanoparticle S1, and peaks corresponding to the Q unit structure of the silica nanoparticle S1. The peak areas of the peaks corresponding to the D1 unit structure, the peak areas of the peaks corresponding to the D2 unit structure, and the peak areas of the peaks corresponding to the Q unit structure are respectively S DD D1, S DD D2, S DD When Q is the case, The ratio (A / B) of A given by equation (1) to B given by equation (2) below is between 4.0 and 14.0, A={(S CP D1+S CP D2) / S CP Q × 100 B={(S DD D1+S DD D2) / S DD Q × 100 For the sample obtained by washing the silica fine particles S1 with hexane 29 In the spectrum obtained by Si-NMR·DD / MAS, there are peaks corresponding to the D1 unit structure, the D2 unit structure, and the Q unit structure of the sample, and the peak areas of the peaks corresponding to the D1 unit structure, the D2 unit structure, and the Q unit structure are respectively defined as S DDW D1, S DDW D2, S DDW When Q is the case, A toner characterized in that the value of C given by the following equation (3) is 1.0 or greater. C={(S DDW D1+S DDW D2) / S DDW Q × 100 (Configuration 2) The toner according to configuration 1, wherein the value of C is 5.0 or greater. (Composition 3) The toner according to configuration 1 or 2, wherein the number-average particle size of the silica fine particles S1 is 5.0 nm or more and 500.0 nm or less. (Composition 4) The BET specific surface area of ​​the silica fine particles S1 at a temperature of 30°C and a relative humidity of 80% is 1 m². 2 The amount of water absorbed per unit is 0.010 cm³. 3 / m 2 ~0.100cm 3 / m 2 The toner described in any of configurations 1 to 3. (Composition 5) A two-component developer having toner and a magnetic carrier, The magnetic carrier has magnetic carrier core particles and a resin coating layer formed on the surface of the magnetic carrier core particles. A two-component developer characterized in that the toner is the toner described in any of components 1 to 4. (Composition 6) The resin in the aforementioned resin coating layer is A monomer unit comprising an (meth)acrylic acid ester having an alicyclic hydrocarbon group, and A two-component developer according to configuration 5, having monomer units made of macromonomers represented by the following formula (B). TIFF0007867851000015.tif18153 (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, and 2-ethylhexyl methacrylate. 3 (This is either H or CH3.)

Claims

1. A two-component developer having toner and a magnetic carrier, The magnetic carrier has magnetic carrier core particles and a resin coating layer formed on the surface of the magnetic carrier core particles. The resin in the resin coating layer has monomer units of (meth)acrylic acid ester having alicyclic hydrocarbon groups, The toner comprises toner particles containing a binder resin and silica fine particles S1 on the surface of the toner particles. The weight-average particle size of the toner is 4.0 μm or more and 15.0 μm or less. The number-average particle size of the silica fine particles S1 is 20.0 nm or more and 80.0 nm or less. The silica fine particles S1 ２９ In Si-NMR measurements, a peak corresponding to the silica fine particle S1 was observed. For the silica fine particles S1 ２９ In the spectrum obtained by the Si-NMR CP / MAS method, there are peaks corresponding to the D1 unit structure of the silica nanoparticle S1, peaks corresponding to the D2 unit structure of the silica nanoparticle S1, and peaks corresponding to the Q unit structure of the silica nanoparticle S1, and the peak area of ​​the peak corresponding to the D1 unit structure, the peak area of ​​the peak corresponding to the D2 unit structure, and the peak area of ​​the peak corresponding to the Q unit structure are respectively S ＣＰ D1, S ＣＰ D2, S ＣＰ Q: For the silica fine particles S1 ２９ In the spectrum obtained by the Si-NMR DD / MAS method, there are peaks corresponding to the D1 unit structure, the D2 unit structure, and the Q unit structure of the silica fine particles S1. Let the peak area of the peak corresponding to the D1 unit structure, the peak area of the peak corresponding to the D2 unit structure, and the peak area of the peak corresponding to the Q unit structure be S ＤＤ D1, S ＤＤ D2, S ＤＤ Q, then The ratio (A / B) of A given by equation (1) to B given by equation (2) below is between 10.0 and 12.0, A={(S ＣＰ D1+S ＣＰ D2) / S ＣＰ Q}×100・・・(1) B={(S ＤＤ D1+S ＤＤ D2) / S ＤＤ Q}×100・・・(2) For the sample obtained by washing the silica fine particles S1 with hexane ２９ In the spectrum obtained by the Si-NMR DD / MAS method, the peaks corresponding to the D1 unit structure of the sample, the peaks corresponding to the D2 unit structure of the sample, and the peaks corresponding to the Q unit structure of the sample are shown. There exists a peak, and the peak area of ​​the peak corresponding to the D1 unit structure, the peak area of ​​the peak corresponding to the D2 unit structure, and the peak area of ​​the peak corresponding to the Q unit structure are each S ＤＤＷ D1, S ＤＤＷ D2, S ＤＤＷ When we call it Q, A two-component developer characterized in that the value of C given by the following formula (3) is 1.0 or greater. C={(S ＤＤＷ D1+S ＤＤＷ D2) / S ＤＤＷ Q}×100・・・(3)

2. The two-component developer according to claim 1, wherein the value of C is 5.0 or greater.

3. The BET specific surface area of ​​the silica fine particles S1 at a temperature of 30°C and a relative humidity of 80% is 1 m². ２ The amount of water adsorbed per unit is 0.010 cm³. ３ / m ２ ~0.100cm ３ / m ２ A two-component developer according to claim 1 or 2.

4. The two-component developer according to claim 1, 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, and 2-ethylhexyl methacrylate. ３ is H or CH ３ (That is the case.)

5. The two-component developer according to claim 1, wherein the silica fine particles S1 are silica fine particles surface-treated with reactive silicone oil at both ends.

6. The two-component developer according to claim 5, wherein the reactive silicone oils at both ends are represented by the following chemical formula (Z). (In formula (Z), R1 and R2 are each independently a hydroxyl group, and R3 is a hydroxyl group or a C1 alkyl group. n and m are the average number of repeating units, where n is 1 or more and 200 or less, and m is 1 or more and 200 or less.)

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