toner

Abstract

To provide a toner excellent in scratch resistance.SOLUTION: A toner has toner particles containing a binder resin and ester wax, and silica fine particles A. The number average particle diameter of the toner is 4.0 μm or more and 15.0 μm or less. The number average particle diameter of the silica fine particles A is 60 nm or more and 500 nm or less. The absolute value of the difference between the SP value (cal / mol)1 / 2 calculated from a straight-chain siloxane structure specified from the 29Si-NMR DD / MAS measurement of the silica fine particles and the SP value (cal / mol)1 / 2 of the ester wax is 0.6(cal / mol)1 / 2 or less.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a toner for developing an electrostatic charge image used in an electrophotographic method, an electrostatic recording method, and the like.

Background Art

[0002] In recent years, full-color copiers using the electrophotographic method have been widely spread and started to be applied to the printing market. In the printing market, high speed, high image quality, and high stability have been required. In addition, it has also been required that the image quality of the obtained product is not impaired. In particular, performance exceeding the conventional level has been required for the heat resistance and rubbing resistance of the obtained product. The rubbing resistance in the present disclosure means the ease of damage or the difficulty of peeling when the image surface is rubbed. In order to improve the rubbing resistance, the following is required. That is, when the image surface is rubbed by another medium or the like, if the image surface frictional force between the image surface and the rubbing medium is small, it becomes difficult for the image to peel or be damaged. In order to reduce this image surface frictional force, it is important that the surface of the fixed image maintains slipperiness. The wax layer has this function in the fixed image and exists on the outermost surface of the image when a toner added with wax is heat-fixed. An example of wax used is ester wax. Since it has high compatibility with the binder resin and low crystallinity, it has excellent low-temperature fixing properties. Therefore, an example in which ester wax is added to make the fixed image of the toner have releasability and lower the fixing temperature can be cited (Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

[0004] To achieve an even higher level of scratch resistance for fixed images, toners present several challenges. As mentioned earlier, in order to maintain abrasion resistance, it is necessary to keep the frictional force between the toner layer and the abrasive media low, and for this to be done, it is necessary to maintain the wax layer on the image surface. Therefore, if the surface wax layer peels off, the frictional force increases, which can cause the image to peel off. The inventors considered and investigated the factors causing the wax layer to peel off as follows: In addition to the wax, external additives added to the toner are observed to be present beneath the wax layer on the surface of the fixed image. However, if the affinity between these external additives and the wax is low, the force acting between the external additives and the wax layer is small, leading to the detachment of the wax layer. Therefore, we investigated whether it would be possible to reduce toner layer peeling by increasing the affinity between the surface treatment groups of silica microparticles, which are mainly added as an external additive, and the ester wax. Specifically, we attempted to improve the toner by reducing the SP value difference between the ester wax and the surface treatment groups of the silica microparticles, based on the toner described in Patent Document 2. However, this did not result in an improvement in abrasion resistance. This is thought to be because, with the small particle size silica microparticles that have been used conventionally, there are many parts of the toner's binder resin component located beneath the wax layer that are not covered by the external additive, so sufficient affinity with the wax layer could not be added. The objective of the present invention is to provide a toner with excellent abrasion resistance in order to solve the above-mentioned problems. [Means for solving the problem]

[0005] The present invention relates to a toner having toner particles containing a binder resin and an ester wax, and silica fine particles A, 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 A is 60 nm or more and 500 nm or less. The silica fine particles A 29 In DD / MAS measurements of Si-NMR, the Si in the structure represented by the following formula (1) a Peak PD1 corresponds to the silicon atom shown, and Si in the structure represented by the following formula (2). b A peak PD2 corresponding to the silicon atom shown was observed, When the peak areas are denoted as SD1 and SD2, The area ratio of SD1 and SD2 is calculated, and the SP value (cal / mol) is calculated from the linear siloxane structure where the area ratio corresponds to the relative abundance of structural formulas (1) and (2). 1 / 2 And the SP value (cal / mol) of the ester wax 1 / 2 The absolute value of the difference between them is 0. 4 (cal / mol) 1 / 2 Below the law of nature, The above SD1 and SD2 result in (SD1+SD2) / SD1 being between 3.0 and 7.5. The ester wax has a linear alkyl structure with 18 to 24 carbon atoms. This relates to toner characterized by the following features.

[0006] [ka] [Effects of the Invention]

[0007] According to the present invention, a toner with excellent abrasion resistance can be provided. [Brief explanation of the drawing]

[0008] [Figure 1] This is a schematic diagram of a heat treatment apparatus suitable for surface-treating toner particles mixed with external silica microparticles using hot air. [Modes for carrying out the invention]

[0009] In this invention, unless otherwise specified, the descriptions of a numerical range, such as "greater than or equal to XX and less than or equal to XX" or "XX to XX," mean a numerical range that includes the lower and upper limits, which are the endpoints.

[0010] 〔Features of the Present Invention〕 The inventors have found that a toner having unprecedented excellent abrasion resistance can be obtained.

[0011] The reason for obtaining the effect of the present invention is considered as follows.

[0012] As described above, it is observed that in the fixed image of the toner, in addition to the wax, the external additives added to the toner are arranged under the wax layer on the surface layer of the fixed image. However, when the affinity between the external additive and the wax is low, the force acting between the external additive and the wax layer is small, so it is considered that the wax layer will peel off therefrom. In addition, even when the affinity between the external additive and the wax layer is high, if the particle diameter of the silica fine particles is small, the affinity cannot be sufficiently exhibited, the toner layer is peeled off, and it is considered that the abrasion resistance cannot be sufficiently improved.

[0013] Of silica fine particles A 29 In the DD / MAS measurement of Si-NMR, Si in the structure represented by the following formula (1) a The peak PD1 corresponding to the silicon atom represented by and Si in the structure represented by the following formula (2) b The peak PD2 corresponding to the silicon atom represented by are observed, <00,00169>The area ratio of PD1 and PD2 is calculated, and the SP value (cal / mol) calculated from the linear siloxane structure in which the area ratio becomes the abundance ratio of the structural formulas (1) and (2) 1 / 2 And the SP value (cal / mol) of the ester wax 1 / 2 By making the absolute value of the difference from 0.6 (cal / mol) 1 / 2 Or less, the affinity between the wax layer and the surface treatment group of the silica fine particles A is increased, so it is considered that it becomes possible to contribute to the abrasion resistance. <00,00170>

[0014] Furthermore, by making the particle diameter of the silica fine particles 60 nm or more and 500 nm or less, the surface treatment group of the ester wax and the silica fine particles exhibit higher affinity, and it is considered that the abrasion resistance is improved.

[0015] In other words, the toner of the present invention is a toner having toner particles containing a binder resin and an ester wax, and silica fine particles A, 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 A is 60 nm or more and 500 nm or less. The silica fine particles A 29 In DD / MAS measurements of Si-NMR, the Si in the structure represented by the following formula (1) a Peak PD1 corresponds to the silicon atom shown, and Si in the structure represented by the following formula (2). b Peaks PD2 and SD2, corresponding to the silicon atoms shown, were observed, and when the areas of the peaks are denoted as SD1 and SD2, The area ratio of SD1 and SD2 is calculated, and the SP value (cal / mol) is calculated from the linear siloxane structure where the area ratio corresponds to the relative abundance of structural formulas (1) and (2). 1 / 2 And the SP value (cal / mol) of the ester wax 1 / 2 The absolute value of the difference is 0.6 (cal / mol). 1 / 2 The toner is characterized by the following:

[0016] [ka]

[0017] [Ester wax] The toner of the present invention contains ester wax. Generally, ester wax has lower crystallinity compared to hydrocarbon waxes and the like, making it easy to design for a low melting point. Therefore, it is preferably used for the purpose of improving the low-temperature fixing properties of the toner.

[0018] As the ester wax, specifically, for example, behenyl behenate, stearyl stearate, pentaerythritol tetrabehenate, pentaerythritol tetrastearate, dipentaerythritol tetrastearate, glycerin tribehenate, glycerin tristearate, diglycerin hexabehenate, stearyl sebacate, trimethylolpropane behenate, distearyl succinate, glycerin 1,2-hydroxystearate, glycerin monobehenate, tristearyl citrate and other monoester waxes, polyfunctional ester waxes, etc. can be used.

[0019] Among these, from the viewpoint of obtaining scratch resistance, it is preferable to have a linear alkyl structure with 18 to 24 carbon atoms, and for example, behenyl behenate, stearyl stearate, etc. are preferably used. [[ID=​​​​​​​​​​​​​​​​​​​​ The above SP value can be calculated using Fedors' formula. Here, the values ​​of Δei and Δvi were taken from Tables 3-9 of "Evaporation energy and molar volume (25°C) of atoms and atomic groups" found on pages 54-57 of "Basic Science of Coatings" (1986 (Maki Shoten)). Formula: δi = [Ev / V] 1 / 2 =[Δei / Δvi] 1 / 2 Ev: Evaporation energy V: Molar volume Δei: Evaporation energy of an atom or group of atoms of component i Δvi: Molar volume of the atom or group of atoms of component i

[0022] For example, the SP value of a dimethyl silicone chain is composed of repeating units of the atomic group (Si) × 1 + (-CH3) × 2 + (-O-) × 1, and the SP value can be calculated using the following formula. δi = [Δei / Δvi] 1 / 2 =[{(810)×1+(1125)×2+(800)×1} / {(0)×1+(33.5)×2+(3.8)×1}] 1 / 2 Therefore, the SP value (δi) is 7.4.

[0023] The unit of SP value in this invention is (cal / mol). 1 / 2 However, 1 (cal / mol) 1 / 2 = 2.046 (J / mol) 1 / 2 (J / mol) 1 / 2 It can be converted to the following units.

[0024] <Surface treatment group for silica microparticles A> The siloxane molecular chains (siloxane chains) present on the surface of the silica nanoparticles used in this invention are considered to be as follows. Here, 29 In Si-solid-state NMR measurements, the DD / MAS measurement method, 29 This method is described as Si-NMR·DD / MAS method.

[0025] First, let's explain the bonding states of silicon atoms. The bonding states of silicon atoms discussed in this invention are the D1 unit structure, the D2 unit structure, and the Q unit structure.

[0026] 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.

[0027] 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.

[0028] 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.

[0029] 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.

[0030] [ka] (R in the formula) 1 , R 2 , R 3 , R 4 , R 5 Each of these independently represents either a hydrogen atom or an alkyl group having 1 or 2 carbon atoms.

[0031] 29 In the Si-NMR·DD / MAS measurement method, all silicon atoms in the sample are observed, thus providing information about the silicon atom content.

[0032] 29In the spectrum obtained by Si-NMR·DD / MAS measurement, the peak area originating from the D1 unit structure is S DD Let D1 be the peak area derived from the D2 unit structure, and S be the peak area derived from the D2 unit structure. DD Let D2 be the peak area derived from the Q unit structure, and S be the peak area derived from the Q unit structure. DD When Q is denoted by the formula below, the value B calculated by the formula below represents the proportion of D unit structures present in 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 silica raw material surface is increased. B={(S DD D1+S DD D2) / S DD Q × 100

[0033] In the present invention, the above R 1 , R 2 , R 3 , R 4 , is CH3, R 5 The surface is treated with a structure that has H. This reduces the absolute difference in SP values ​​between the surface treatment group and the ester wax, as described later, thereby improving affinity.

[0034] The surface treatment group may react with and bond to the silanol groups on the surface of the silica material, or it may remain attached to the silica surface without bonding. Whether the surface treatment group is bonded to the silanol groups can be confirmed by washing silica nanoparticles A with hexane, drying them, and then measuring the NMR spectrum. In other words, the difference in the surface treatment group observed before and after hexane washing reveals the state of the treatment group that was attached to the surface without reacting with the silanol groups of the silica material.

[0035] The method for calculating the SP value varies depending on whether the surface treatment group is bonded to the silanol group of the silica matrix or is attached to the surface. When it is bonded to the silanol group, since (1) calculated by the NMR exists at one end, the SP value of the surface-treated structure at one end can be calculated from the area ratio of (1) and (2). On the other hand, when it is not bonded to the silanol group, since (1) calculated by the NMR exists at both ends, the number of structures of (2) can be determined from the area ratio such that the structure of (2) exists between the structures of (1) using the area of (1) as both ends.

[0036] The washing of silica particles with hexane is carried out as follows.

[0037] <Hexane Washing Method of Silica Particles>[ Weigh 1.0 g of silica particles into a 50 ml screw tube and add 20 ml of normal hexane. Then, extract with an ultrasonic homogenizer (VP-050 manufactured by TAITEC) at an intensity of 20 (output 10 W) for 10 minutes. Separate the obtained extract with a centrifuge, remove the supernatant, and distill off normal hexane from the obtained wet sample with an evaporator to obtain silica particles after hexane washing.

[0038] <NMR Measurement Method>[ As a pretreatment for NMR measurement, separate silica particles from toner particles by the following method.

[0039] [Separation Method of Silica Particles from Toner Particles][ Weigh 20 g of a 10 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.

[0040] The sample is placed in an Iwaki Sangyo Co., Ltd. "KM Shaker" (model: V.SX), set to speed 50, and shaken for 30 seconds. This causes the silica microparticles to migrate from the surface of the toner particles to the aqueous solution. Subsequently, in the case of magnetic toner containing magnetic material, the toner particles are restrained using a neodymium magnet, and the silica microparticles S1 that have migrated to the supernatant are separated. The settled toner is then dried under vacuum (40°C / 24 hours) to obtain the sample.

[0041] In the case of non-magnetic toner, the toner and the silica fine particles S1 that have migrated to the supernatant liquid are separated using a centrifuge (H-9R; manufactured by Kokusan Co., Ltd.) (at 1000 rpm for 5 minutes).

[0042] Furthermore, NMR measurements of silica particles after hexane washing can be performed in the same manner as described above.

[0043] [ 29 [Method for measuring Si-NMR] solid 29 The specific measurement conditions for Si-NMR are as follows: Equipment: JNM-ECA400 (JEOL RESONANCE) Temperature: room temperature Measurement method: DD / MAS method 29 Si 45° Sample tube: Zirconia 8.0 mmφ Sample: A test tube filled with silica particles in powder form. Sample rotation speed: 6kHz Relaxation delay: 90 seconds Scan: 1000

[0044] Also, solid 29 The CP / MAS measurement conditions for Si-NMR (solid state) are as follows: Equipment: 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 particles in powder form. Sample rotation speed: 6kHz Relaxation delay: 5 seconds Scan: 10000

[0045] In the NMR spectra obtained by the measurements described above, the peak area of ​​the D unit structure is obtained by calculating the integral value of the peaks originating from the siloxane chains that appear around -10 to 40 ppm. Similarly, the peak area of ​​the Q unit structure is obtained by calculating the integral value of the peaks originating from the siloxane chains that appear around -90 to 125 ppm. This calculation is performed on spectra obtained by the DD / MAS method and spectra obtained by the CP / MAS method.

[0046] The treatment agent for the surface of the silica nanoparticles is not particularly limited, as long as the silica nanoparticles satisfy the specifications regarding the D unit structure, Q unit structure, and SP value. However, it is preferable to use a treatment agent containing a siloxane structure.

[0047] The surface treatment agent containing siloxane bonds is not particularly limited, and known materials can be used. To easily obtain the above physical properties, it is preferable to perform a surface treatment on the silica fine particle substrate.

[0048] Surface treatment agents containing siloxane bonds include, for example, silicone oils such as dimethyl silicone oil; silicone oils in which the side chains or terminals of dimethyl silicone oil are modified with organic groups, such as methyl hydrogen silicone oil, methylphenyl silicone oil, alkyl-modified silicone oil, chloroalkyl-modified silicone oil, chlorophenyl-modified silicone oil, fatty acid-modified silicone oil, polyether-modified silicone oil, alkoxy-modified silicone oil, carbinol-modified silicone oil, amino-modified silicone oil, and fluorine-modified silicone oil; and cyclic siloxanes such as hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, and decamethylcyclopentasiloxane.

[0049] The surface treatment agent containing siloxane bonds is preferably a cyclic siloxane. More preferably, it is a cyclic siloxane with up to 10 membered rings. The cyclic siloxane may have substituents on some of the methyl groups bonded to the silicon atoms. Among the cyclic siloxanes, it is preferable that it be at least one selected from the group consisting of hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, and decamethylcyclopentasiloxane. From the viewpoint of ease of controlling chain length and ease of purification, it is even more preferable to include octamethylcyclotetrasiloxane.

[0050] The method for surface treatment of the silica microparticle substrate is not particularly limited and can be carried out by contacting the silica microparticle substrate with a surface treatment agent containing siloxane bonds. From the viewpoint of uniformly treating the surface of the silica microparticle substrate and easily achieving the above physical properties, it is preferable to contact the silica microparticle substrate with the surface treatment agent in a dry manner. As will be described later, examples of methods include contacting the silica microparticle substrate with the vapor of the surface treatment agent, or spraying the undiluted solution of the surface treatment agent or a diluted solution with various solvents into contact with the silica microparticle substrate.

[0051] The processing temperature is not particularly limited, as it varies depending on the reactivity of the surface treatment agent used. It is preferable to mix the silica fine particle substrate and the surface treatment agent and heat-treat them at a temperature of 250°C or higher. More preferably, it is between 250°C and 380°C.

[0052] The processing time varies depending on the processing temperature and the reactivity of the surface treatment agent used, but is preferably 5 minutes to 300 minutes, more preferably 30 minutes to 240 minutes, and even more preferably 60 minutes to 200 minutes. The processing temperature and processing time for surface treatment being within the above range is preferable from the viewpoint of allowing the treatment agent to react sufficiently with the silica fine particle substrate, and from the viewpoint of production efficiency.

[0053] For contact between the surface treatment agent and the silica microparticle substrate, it is preferable to contact the surface treatment agent vapor under reduced pressure or in an inert gas atmosphere such as a nitrogen atmosphere. Using the vapor contact method makes it easier to remove surface treatment agents that do not react with the silica microparticle surface and facilitates control of the full width at half maximum (WD2) of the peak corresponding to the silicon atom having a D2 unit structure. When using the vapor contact method, it is preferable to perform the treatment at a treatment temperature above the boiling point of the surface treatment agent. The vapor contact may be performed in multiple steps (e.g., 2 to 3 times).

[0054] Silica nanoparticles A are obtained by treating a silica nanoparticle substrate with a cyclic siloxane, and it is more preferable that the treatment is carried out at a treatment temperature of 250°C or higher.

[0055] Since cyclic siloxanes react with the OSiOH groups on the surface of silica nanoparticle substrates via ring-opening reactions, a D1 unit structure can be effectively obtained.

[0056] The amount of surface treatment agent is preferably 40 to 150 parts by mass, and more preferably 70 to 140 parts by mass, per 100 parts by mass of silica fine particle substrate. In particular, when surface treatment is performed by contacting with a cyclic siloxane using vapor, it is preferable to add 70 parts by mass or more, and more preferably 100 parts by mass or more, per 100 parts by mass of silica fine particle substrate. This makes it possible to surface treat the silica fine particle substrate more uniformly.

[0057] Furthermore, when performing surface treatment under reduced pressure, it is preferable that the pressure due to the vapor of the surface treatment agent in the container be between 0.1 Pa and 100.0 Pa, and more preferably between 1.0 Pa and 10.0 Pa. By maintaining this pressure range, the frequency of contact between the vapor molecules of the surface treatment agent is reduced, suppressing chemical reactions between the surface treatment agents and allowing the chemical reaction between the surface treatment agent in contact with the surface of the silica microparticle substrate to proceed preferentially.

[0058] Furthermore, reaction byproducts generated by the chemical reaction between the silica microparticle substrate and the surface treatment agent can be easily removed from the vicinity of the silica microparticle surface, allowing the surface treatment agent to come into closer contact with the surface of the silica microparticle substrate, and enabling more uniform surface treatment of the silica microparticle substrate.

[0059] Furthermore, when performing surface treatment under reduced pressure, it is preferable to perform a degassing treatment by heating the silica microparticle substrate under reduced pressure to remove moisture and other substances adsorbed on the surface of the silica microparticle substrate before bringing the surface treatment agent into contact with the surface of the silica microparticle substrate. This makes it easier for the surface treatment agent to come into contact with the surface of the silica microparticle substrate, allowing for more uniform surface treatment of the silica microparticle substrate. In addition, from the viewpoint of making it easier for the surface treatment agent to come into contact with the surface of the silica microparticle substrate, it is also preferable to repeat the degassing treatment and the surface treatment of the silica microparticles with the surface treatment agent.

[0060] The surface treatment group obtained by the method described above preferably has a siloxane chain applied to the silica surface such that (SD1 + SD2) / SD1 is between 3.0 and 10.0. This range is preferable because it increases the affinity with ester wax, thereby improving abrasion resistance.

[0061] Furthermore, within the scope of satisfying the provisions of the present invention, after obtaining silica nanoparticles A by the method described above, further treatment may be performed using the surface treatment agent containing the siloxane bond described above. The method of treatment is not particularly limited, and for example, it can be performed by bringing the surface treatment agent containing the siloxane bond into contact with the silica nanoparticles.

[0062] The number-average particle size of the silica nanoparticles must be between 60 nm and 500 nm. Having the silica nanoparticles in this particle size range improves the affinity between the silica nanoparticles and the wax layer, thus improving abrasion resistance. Furthermore, a number-average particle size of 80 nm to 200 nm is preferable. Even more preferable is a particle size between 100 nm and 150 nm, as having the silica nanoparticles in this range further improves abrasion resistance.

[0063] Furthermore, the mixture may contain additives other than silica microparticles. These may include silica microparticles other than silica microparticles, or inorganic microparticles other than silica microparticles, or organic microparticles such as resin microparticles. 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 microparticles and SS2 is the number-average particle size of the additive used in combination. In this case, embedding of the silica microparticles is suppressed even during long-term use or use in high-temperature environments, which further improves abrasion resistance and is therefore preferable.

[0064] <Number-average particle size of silica microparticles> The number-average particle size of silica microparticles A 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.

[0065] Alternatively, the number and particle size of silica microparticles S1 present on the surface of the toner particles can be determined by observing the toner particles with a scanning electron microscope (SEM). The average value obtained by measuring 100 toner particles is used as the number-average particle size.

[0066] [Other components of toner] <Binding resin for toner particles> The toner particles applicable to this invention can use known binder resins. For example, the following are examples of binder resins.

[0067] 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, petroleum resins. Preferably, the resins used are styrene copolymer resins, polyester resins, and hybrid resins obtained by mixing polyester resin and styrene copolymer resin or by partial reaction of both. Preferably, the resin is a polyester resin. 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.

[0068] Examples of divalent 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; alkenylsuccinic acids or alkylsuccinic acids with an average number of carbon atoms of 1 to 50, or their anhydrides or lower alkyl esters; unsaturated dicarboxylic acids such as fumaric acid, maleic acid, citraconic acid, and itaconic acid, or their anhydrides or lower alkyl esters. Examples of alkyl groups in lower alkyl esters include methyl, ethyl, propyl, and isopropyl groups.

[0069] Examples of divalent alcohol components that make up polyester resin include the following:

[0070] 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).

[0071] [ka] (In formula (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.)

[0072] [ka] (In formula (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.)

[0073] In addition to the divalent carboxylic acid compounds and divalent alcohol compounds mentioned above, the components of the polyester resin may also include trivalent or higher carboxylic acid compounds and trivalent or higher alcohol compounds as components.

[0074] Examples of trivalent or higher carboxylic acid compounds include trimellitic acid, trimellitic anhydride, and pyromellitic acid, although there are no particular limitations. Examples of trivalent or higher alcohol compounds include trimethylolpropane, pentaerythritol, and glycerin.

[0075] In addition to the compounds mentioned above, the components of the polyester resin may also include monovalent carboxylic acid compounds and monovalent alcohol compounds. Specifically, examples of monovalent carboxylic acid compounds 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.

[0076] Other examples of monohydric alcohol compounds include behenyl alcohol, ceryl alcohol, melicyl alcohol, and tetracontanol.

[0077] <Coloring agent> The toner of the present invention can be used as any of the following toners: a magnetic one-component toner, a non-magnetic one-component toner, or a non-magnetic two-component toner.

[0078] 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.

[0079] 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.

[0080] Examples of colorants used when used as non-magnetic one-component toners and non-magnetic two-component toners include the following:

[0081] 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.

[0082] Suitable colorants for the yellow color include pigments or dyes. Examples of pigments include CI Pigment Yellow 1, 2, 3, 4, 5, 6, 7, 10, 11, 12, 13, 14, 15, 17, 23, 62, 65, 73, 74, 81, 83, 93, 94, 95, 97, 98, 109, 110, 111, 117, 120, 127, 128, 129, 137, 138, 139, 147, 151, 154, 155, 167, 168, 173, 174, 176, 180, 181, 183, 191, and CI Bat Yellow 1, 3, 20. Examples of dyes include CI Solvent Yellow 19, 44, 77, 79, 81, 82, 93, 98, 103, 104, 112, and 162. These can be used individually or in combination of two or more.

[0083] 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.

[0084] 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.

[0085] 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.

[0086] <Charge control agent> The toner can use known charge control agents as charge control agents. Known charge control agents 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. Aromatic hydroxycarboxylic acids are preferred as the carboxylic acid derivatives. Charge control resins can also be used. One or more charge control agents may be used in combination as needed. It is preferable to add the charge control agent in an amount of 0.1 parts by mass to 10 parts by mass per 100 parts by mass of the binder resin.

[0087] [Addition of external additives to toner particles and heat treatment] In the toner of the present invention, it is preferable to add silica fine particles S1 having the configuration of the present invention as an external additive. The amount of silica fine particles S1 added to the toner particles is preferably 0.01 parts by mass or more and 10.00 parts by mass or less per 100 parts by mass of toner particles, and more preferably 1.0 part by mass or more and 10.00 parts by mass or less. Even more preferably it is 1.0 part by mass or more and 5.00 parts by mass or less. This allows the silica fine particles to properly coat the toner particles, the effects of the present invention to be expressed more effectively, the electrostatic stability is improved, the fluctuation in image density is small even when the environment changes, and changes in image density during continuous printing can be suppressed.

[0088] External addition to toner particles can be performed by mixing the toner particles and the external additive using the following types of mixers. Examples of mixers 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 Corporation); Spiral Pin Mixer (manufactured by Taiheiyo Kiko Co., Ltd.); and Redigge mixer (manufactured by Matsubo Co., Ltd.).

[0089] In the present invention, it is preferable that the toner particles are surface-treated with hot air. Furthermore, it is preferable to apply the hot air surface treatment while silica fine particles are attached to the surface of the toner particles before the hot air treatment. This is preferable because it prevents the silica fine particles from moving across the surface of the toner particles even during long-term use, reduces the variation of silica fine particles as seen from the toner surface layer, ensures an area that contributes to the affinity of the wax layer on the fixed image, and thus improves abrasion resistance.

[0090] The following provides a specific example of a method for performing surface treatment on toner particles using hot air, using the heat treatment apparatus shown in Figure 1. In this example, toner particles will be referred to as the workpiece.

[0091] 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.

[0092] At this time, the flow of the material to be processed supplied to the processing chamber 6 is restricted by a restricting means 9 provided within the processing chamber 6 to restrict 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 within the processing chamber 6, and then cooled. The hot air for heat-treating the supplied material to be processed 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 swirling manner by the swirling member 13 for swirling the hot air. In this configuration, 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 the blades (note that 11 indicates the outlet of the hot air supply means). The temperature of the hot air supplied into the processing chamber 6 is preferably 100°C or more and 300°C or less at the outlet of the hot air supply means 7, and more preferably 130°C or more and 190°C or less. 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 adjusted 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. In addition, the absolute moisture content of the cold air is 0.5 g / m³. 3 More than 15.0g / m 3 The following is preferable:

[0093] 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.

[0094] Furthermore, the powder particle supply port 14 is positioned so that the swirling direction of the supplied material to be processed and the swirling direction 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 swirling direction of the 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 the same. As a result, turbulence does not occur in the processing chamber, the swirling flow within the device is strengthened, and a strong centrifugal force is applied to the material to be processed before heat treatment, further improving dispersibility, making it easier to obtain toner particles with fewer aggregated particles.

[0095] [Toner manufacturing method] The method for producing the toner of the present invention is not particularly limited and can be produced by known methods. Examples include grinding, emulsification and agglutination, suspension polymerization, and dissolution and suspension methods.

[0096] <Grinding Method> Toner particles produced by the grinding method are manufactured, for example, as follows: A 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 melt-kneaded using a hot kneader such as a twin-screw extruder, heated roll, kneader, or extruder. At this time, wax, magnetic iron oxide particles, and metal-containing compounds can also be added. After the molten mixture is cooled and solidified, it is ground and classified to obtain toner particles. At this time, the embedding of silica fine particles on the surface of the toner particles can be controlled by adjusting the exhaust temperature during fine grinding. The toner particles and silica additives are mixed using a mixer such as a Henschel mixer to obtain toner.

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

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

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

[0100] 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.

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

[0102] Examples of sieving devices used to separate coarse particles include: Ultrasonic (manufactured by Koei Sangyo Co., Ltd.); Resona Sieve, Gyro Shifter (manufactured by Tokuju Kogyo Co., Ltd.); Vibrasonic System (manufactured by Dalton Co., Ltd.); Soniclean (manufactured by Shinto Kogyo Co., Ltd.); Turbo Screener (manufactured by Turbo Engineering Co., Ltd.); Micro Shifter (manufactured by Makino Sangyo Co., Ltd.); and circular vibrating screen.

[0103] <Emulsification aggregation method> Toner particles produced by the emulsification and agglutination method are manufactured, for example, as follows:

[0104] • Steps to prepare a resin fine particle dispersion (preparation steps): 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.

[0105] 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.

[0106] 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.

[0107] 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.

[0108] 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.

[0109] ·Agglomeration process: The aggregation process involves, for example, mixing a resin microparticle dispersion with a coloring agent microparticle dispersion, an aliphatic hydrocarbon 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.

[0110] 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.

[0111] 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.

[0112] Aliphatic hydrocarbon fine particle 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 and polymer dispersants that impart dispersion stability can be added as needed.

[0113] 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.

[0114] 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 devices, homogenizers, mixers, etc.

[0115] ·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.

[0116] 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.

[0117] 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.

[0118] 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.

[0119] ·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.

[0120] • Cleaning process: By repeatedly washing and filtering the resin particles produced through the manufacturing process, impurities in the resin particles can be removed.

[0121] 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.

[0122] 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 of 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] <Dissolution and suspension method> Toner particles produced by the dissolution-suspension method are manufactured, for example, as follows:

[0126] 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.

[0127] The dissolution-suspension method is applicable to any resin component that dissolves in an organic solvent, and it also allows for easy shape control depending on the conditions during solvent removal.

[0128] The following describes, but is not limited to, a toner manufacturing method using the dissolution suspension method.

[0129] ·Resin component dissolution process: In the resin component dissolution step, the binder resin, and optionally other components such as colorants, aliphatic hydrocarbons, and silicone oil, are dissolved or dispersed in an organic solvent to prepare the resin composition.

[0130] 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.

[0131] 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, aliphatic hydrocarbons, 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.

[0132] On the other hand, the colorants, aliphatic hydrocarbons, and silicone oils do not need to be dissolved in organic solvents; they may be dispersed. When using the colorants, aliphatic hydrocarbons, and silicone oils in a dispersed state, it is preferable to disperse them using a disperser such as a bead mill.

[0133] ·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.

[0134] Water is the primary water-based medium used.

[0135] 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.

[0136] As a result, the toner tends to have better blocking resistance and a better particle size distribution.

[0137] Examples of monovalent metal salts include sodium chloride, potassium chloride, lithium chloride, and potassium bromide, of which sodium chloride and potassium chloride are preferred.

[0138] 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.

[0139] The dispersant is not particularly limited, but as an organic dispersant, cationic, anionic, and nonionic surfactants can be used, with anionic surfactants being preferred.

[0140] 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.

[0141] 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.

[0142] 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.

[0143] 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.

[0144] • 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.

[0145] • 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 water washing. Washing removes the dispersant used for granulation. After washing, toner particles can be obtained by filtering and drying, and then classifying as appropriate.

[0146] • Process of 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.

[0147] <Suspension polymerization method> Toner particles produced by suspension polymerization are manufactured, for example, as follows:

[0148] 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, polymerized particles are obtained by polymerizing the polymerizable monomers in the particles made of the polymerizable monomer composition.

[0149] 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.

[0150] Toner particles are obtained by filtering, washing, drying, and classifying the polymerized particles using known methods. Toner can be obtained by mixing the obtained toner particles and external additives using a mixer such as a Henschel mixer.

[0151] The weight-average particle diameter of the toner obtained as described above is preferably 4.0 μm to 15.0 μm. More preferably, it is preferably 4.0 μm to 9.0 μm. This allows the silica fine particles to properly coat the toner particles, optimizes the contact area between the silica fine particles and the toner particles, and allows the effects of the present invention to manifest more effectively, resulting in good electrostatic stability, smaller fluctuations in image density even when the environment changes, and suppression of changes in image density during continuous printing.

[0152] <Method for measuring the weight-average particle size of toner> The weight-average particle size of the toner was measured using the "Coulter Counter Multisizer 3" (registered trademark, manufactured by Beckman Coulter), a precision particle size distribution analyzer using the pore electrical resistance method with a 100 μm aperture tube, and the accompanying dedicated software "Beckman Coulter Multisizer 3 Version 3.51" (manufactured by Beckman Coulter) for setting measurement conditions and analyzing measurement data. Measurements were taken with 25,000 effective measurement channels, and the measurement data was analyzed to calculate the weight-average particle size. The electrolytic aqueous solution used for measurement is prepared by dissolving high-grade sodium chloride in ion-exchanged water to a concentration of approximately 1% by mass; for example, "ISOTON II" (manufactured by Beckman Coulter) can be used.

[0153] Furthermore, before performing the measurements and analysis, the following settings were configured for the dedicated software.

[0154] 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.

[0155] 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 from 2 μm to 60 μm.

[0156] 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 Flash" function of the dedicated software to remove any dirt and air bubbles from inside the aperture tube. (2) Place approximately 30 ml of the electrolytic aqueous solution into a 100 ml flat-bottomed glass beaker, and add approximately 0.3 ml of a diluted solution of "Contaminon N" (a 10% by mass aqueous solution of a pH 7 neutral detergent for cleaning precision measuring instruments, consisting of a nonionic surfactant, anionic surfactant, and organic builder, manufactured by Wako Pure Chemical Industries, Ltd.) diluted three times by mass with deionized water as a dispersant. (3) Two oscillators with an oscillation frequency of 50 kHz are built in with their phases shifted by 180 degrees, and a predetermined amount of deionized water is placed in the water tank of an ultrasonic dispersion device called "Ultrasonic Dispersion System Tetora150" (manufactured by Nikko Bios Co., Ltd.) with an electrical output of 120 W. Approximately 2 ml of the aforementioned Contaminon N is added to this water tank. (4) Place the beaker from (2) into the beaker fixing hole of the ultrasonic disperser and operate the ultrasonic disperser. Then, adjust the height of the beaker so that the resonance state of the liquid surface of the electrolytic aqueous solution inside the beaker is maximized. (5) While irradiating the electrolytic aqueous solution in the beaker described in (4) with ultrasound, add approximately 10 mg of toner to the electrolytic aqueous solution in small amounts and disperse it. Continue the ultrasonic dispersion treatment for another 60 seconds. During ultrasonic dispersion, adjust the water temperature in the tank to be between 10°C and 40°C as appropriate. (6) Using a pipette, the electrolytic aqueous solution (5) containing the dispersed toner is dropped into the round-bottom beaker (1) placed in the sample stand, and the concentration is adjusted to approximately 5%. The measurement is then continued until the number of particles measured reaches 50,000. (7) The measurement data is analyzed using the dedicated software provided with 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).

[0157] [Magnetic carrier] The toner of the present invention may be mixed with a magnetic carrier and used as a two-component developer.

[0158] As magnetic carriers, ordinary magnetic carriers 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 the resin component, or porous magnetic particles containing resin in the voids can be used.

[0159] Various magnetic iron compound particle powders can be used as magnetic material components in magnetic material-dispersed resin particles, including magnetite particle powder, maghemite particle powder, or magnetic iron oxide particle powder containing at least one selected from silicon oxide, silicon hydroxide, aluminum oxide, and aluminum hydroxide; magnetoplanvite-type ferrite particle powder containing barium, strontium, or barium-strontium; and spinel-type ferrite particle powder containing at least one selected from manganese, nickel, zinc, lithium, and magnesium.

[0160] 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.

[0161] Examples of materials for the 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)

[0162] 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.

[0163] The resin-coated 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 the 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 used to coat the surface of the magnetic carrier core particles is preferably 0.1 parts by mass to 5.0 parts by mass per 100 parts by mass of magnetic carrier core particles in order to control the ability to impart charge to the toner.

[0164] 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. Among these, copolymers synthesized using (meth)acrylic acid ester monomers having alicyclic hydrocarbon groups are particularly preferred from the viewpoint of electrostatic stability. 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, and the number of carbon atoms is preferably 3 to 10, and more preferably 4 to 8. These may be used individually or in combination of two or more.

[0165] Furthermore, the copolymerization ratio by mass of methacrylic acid ester monomers 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.

[0166] Furthermore, from the viewpoint of charge stability, it is more preferable that the resin coating layer contains macromonomers as copolymer components to improve adhesion between the magnetic carrier core particles and the resin coating layer and to suppress localized peeling of the resin coating layer. The micromonomer 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.

[0167] An example of a specific macromonomer is shown in formula (B).

[0168] [ka]

[0169] In formula (B), A represents a polymer portion whose polymerization component is one or more compounds selected from the group consisting of methyl acrylate, methyl methacrylate, butyl acrylate, butyl methacrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, styrene, acrylonitrile, and methacrylonitrile, and R 3 It is either H or CH3.

[0170] 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.

[0171] In order to improve the adhesion between the magnetic carrier core particles and the resin coating layer, it is preferable that the copolymerization ratio of the macromonomers in the copolymer used in the resin coating layer is 0.5% by mass or more and 30.0% by mass or less.

[0172] <Measurement of weight-average molecular weight of macromonomers> The weight-average molecular weight is measured using gel permeation chromatography (GPC) following the procedure below.

[0173] First, the sample to be measured is prepared as follows.

[0174] 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.

[0175] 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.

[0176] (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

[0177] 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).

[0178] [Configurations included in embodiments of the present invention] This embodiment includes the following configuration. (Configuration 1) A toner having toner particles containing a binder resin and ester wax, and silica fine particles A, 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 A is 60 nm or more and 500 nm or less. The silica fine particles A 29 In DD / MAS measurements of Si-NMR, the Si in the structure represented by formula (1) above a Peak PD1 corresponds to the silicon atom shown, and Si in the structure represented by formula (2) above. b Peaks PD2 and SD2, corresponding to the silicon atoms shown, were observed, and when the areas of the peaks are denoted as SD1 and SD2, The area ratio of SD1 and SD2 is calculated, and the SP value (cal / mol) is calculated from the linear siloxane structure where the area ratio corresponds to the relative abundance of structural formulas (1) and (2). 1 / 2 And the SP value (cal / mol) of the ester wax 1 / 2 The absolute value of the difference is 0.6 (cal / mol). 1 / 2 A toner characterized by the following: (Configuration 2) The toner according to Configuration 1, wherein the ester wax has a linear alkyl structure with 18 or more carbon atoms and 24 or fewer carbon atoms. (Configuration 3) The toner according to Configuration 1 or 2, wherein (SD1 + SD2) / SD1 is 3.0 or more and 10 or less, based on SD1 and SD2. (Configuration 4) The toner according to any one of Configurations 1 to 3, wherein the number-average particle size of the silica fine particles A is 80 nm or more and 200 nm or less. [Examples]

[0179] 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. Examples 14-18 are for reference only. Unless otherwise specified, parts and percentages are based on mass.

[0180] <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.

[0181] A reflux condenser, moisture separator, N2 gas introduction tube, thermometer, and stirring device were attached to the autoclave, and a condensation polymerization reaction was carried out at 230°C while introducing N2 gas into the autoclave. The reaction time was adjusted to achieve the desired softening point, and after the reaction was completed, the material was removed from the container, cooled, and pulverized to obtain binder resin 1. The softening point of binder resin 1 was 130°C, and the Tg was 57°C. The softening point was measured as follows:

[0182] [Measurement of softening point] The procedure will be performed using a constant-load extrusion type capillary rheometer, the "Flow Characteristics Evaluation Device Flow Tester CFT-500D" (manufactured by Shimadzu Corporation), in accordance with the manual included with the device.

[0183] 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.

[0184] 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".

[0185] The melting temperature in the 1 / 2 method was calculated as follows:

[0186] 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.

[0187] 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

[0188] <Example of manufacturing silica microparticle A> 500 g of fumed silica (silica microparticle substrate) with an average particle size of 120 nm was placed in a stainless steel (SUS304) reaction vessel connected to a vacuum pump. The pressure inside the reaction vessel was reduced to 0.001 Pa, and heating and stirring were performed, controlling the temperature of the reaction vessel to 280°C. After degassing for 30 minutes in this state, octamethylcyclotetrasiloxane vapor was introduced as a surface treatment agent, supplied at a rate of 6 g / min, while the opening of the valve between the vacuum pump and the reaction vessel was adjusted to control the pressure inside the reaction vessel to 1 Pa. In this state, heating and stirring were performed for 20 minutes to surface treat the silica microparticle substrate.

[0189] Subsequently, to remove any unreacted surface treatment agent, the reaction vessel was evacuated under reduced pressure until the pressure reached 0.001 Pa. After 30 minutes of degassing in this state, octamethylcyclotetrasiloxane vapor was again introduced as the surface treatment agent, supplied at a rate of 6 g / min while controlling the pressure in the reaction vessel to 1 Pa. In this state, the silica nanoparticles were subjected to a second surface treatment by heating and stirring for 20 minutes.

[0190] Subsequently, to remove any unreacted surface treatment agent, the reaction vessel was evacuated under reduced pressure until the pressure reached 0.001 Pa. After 30 minutes of degassing in this state, octamethylcyclotetrasiloxane vapor was again introduced as the surface treatment agent, supplied at a rate of 6 g / min while controlling the pressure in the reaction vessel to 1 Pa. In this state, the silica nanoparticles underwent a third surface treatment by heating and stirring for 20 minutes.

[0191] Subsequently, while continuing to heat and stir, the reaction vessel was evacuated under reduced pressure to 0.001 Pa to remove unreacted surface treatment agents, thereby obtaining silica fine particles A1. The physical properties of the obtained silica fine particles A1 are shown in Table 1.

[0192] <Manufacturing of Silica Microparticles A2> 500 g of fumed silica (silica microparticle substrate) with an average particle size of 120 nm was placed in a reaction vessel, and the mixture was heated and stirred under nitrogen purging, with the temperature inside the reaction vessel controlled to 330°C.

[0193] Next, as a surface treatment agent, polydimethylsiloxane (kinematic viscosity at 25°C: 50 mm) 2 A solution prepared by diluting 50 g of silica nanoparticles (average repeating units n=60) with 500 g of hexane was supplied by spray atomization. Subsequently, the silica nanoparticle substrate was surface-treated by heating and stirring for 60 minutes to obtain silica nanoparticles A2. The physical properties of the obtained silica nanoparticles A2 are shown in Table 1.

[0194] <Example of Silica Microparticle Production> 1 kg of fumed silica (silica microparticle raw material; spherical) with a number-average particle size of 120 nm was placed in a reaction vessel and heated while stirring under a nitrogen atmosphere, with the temperature inside the vessel controlled to reach 300°C. Next, a reactive silicone oil with alcohol at both ends (kinematic viscosity at 25°C; 40 mm) was used. 2 Silica nanoparticles A3 were obtained by supplying silica (1000 g / mol / s, equivalent to 1000 g / mol) into 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.

[0195] <Manufacturing example of silica microparticle A4> 1 kg of fumed silica (silica microparticle raw material; spherical) with a number-average particle size of 120 nm was placed in a reaction vessel and heated while stirring under a nitrogen atmosphere, with the temperature inside the vessel controlled to reach 300°C. Next, a single-ended alcohol-type reactive silicone oil (kinematic viscosity at 25°C; 50 mm) was used. 2 Silica nanoparticles A4 were obtained by supplying (500 g / mol / s, functional group equivalent) into 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.

[0196] <Manufacturing examples of silica microparticles A5-9 and B3> Fumed silica (silica microparticle raw material; spherical) with the number-average particle size shown in Table 1 was manufactured in the same manner as silica microparticle A1, except that the treatment agent and treatment conditions were changed as shown in Table 1.

[0197] <Manufacturing of silica microparticles A10 and B1> Fumed silica (silica microparticle raw material; spherical) with the number-average particle size shown in Table 1 was manufactured in the same manner as silica microparticle A2, except that the treatment agent and treatment conditions were changed as shown in Table 1.

[0198] <Example of silica microparticle B2 manufacturing process> 500g of fumed silica (silica microparticle substrate) with an average particle size of 120nm was placed in a reaction vessel, and the mixture was heated and stirred under nitrogen purging, with the temperature inside the reaction vessel controlled to 170°C.

[0199] Next, hexamethyldisilazane vapor was supplied into the reaction vessel at a rate of 10 g / min for 60 minutes as a surface treatment agent. Subsequently, the silica nanoparticle substrate was surface-treated by heating and stirring for 180 minutes.

[0200] [Table 1]

[0201] <Toner manufacturing example 1> • Binding resin 1 100 parts by mass • Behenyl behenate 4 parts by mass • CI Pigment Blue 15:3 4 parts by mass 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.

[0202] The resulting mixture was cooled, coarsely ground in a hammer mill, and then finely ground in a turbo mill.

[0203] The obtained finely ground material was classified using a multi-segment classifier utilizing the Coanda effect to obtain toner base particles 1 with a weight-average particle size (D4) of 6.5 μm.

[0204] Next, silica nanoparticles were added to the obtained toner matrix particles 1 as described below. Toner matrix particles 1:100 parts by mass • Silica fine particles A1: 2.0 parts by mass The above materials were mixed in a Henschel mixer. The Henschel mixer was operated at a rotation speed of 4000 rpm, a rotation time of 2 min, and a heating temperature of room temperature. After this, heat treatment was performed using the surface heat treatment apparatus shown in Figure 1, and some of the silica fine particles were embedded in the surface of the toner matrix particles. The surface heat treatment apparatus was operated with 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 E=3℃, cold air flow rate=1.2m 3 I set it to / min.

[0205] Next, using an air classifier utilizing the Coandă effect (Elbow Jet Lab EJ-L3, manufactured by Nippon Steel Mining Co., Ltd.), fine powder and coarse powder were simultaneously classified and removed to obtain toner particles with silica fine particles A1 buried on the surface. For the heat-treated toner particles thus obtained, external addition treatment of silica fine particles was performed again as follows. · Toner particles 1 with silica fine particles A1 buried on the surface: 100 parts by mass · Silica fine particles A1: 0.6 parts by mass Using a Henschel mixer (product name: FM-10C type, manufactured by Nippon Coke Co., Ltd.), the above materials were mixed at a rotation speed of 67 s -1 (4000 rpm), a rotation time of 2 min, and an external addition temperature of room temperature. After mixing, the mixture was passed through an ultrasonic vibrating sieve with a mesh opening of 54 μm to obtain Toner 1. The surface treatment conditions of Toner 1 are shown in Table 2.

[0206] <Production Examples 2 to 19 of Toner> As shown in Table 2, Toner mother particles 2 to 5 were produced in the same manner as Toner mother particle 1 except that the type of ester wax was changed. Further, Toner 2 to 19 were produced in the same manner as Production Example 1 of the toner except that the type, addition amount, and treatment conditions of the silica fine particles were changed. Note that for Toner 6 to 19, surface heat treatment and re-external addition treatment after external addition of each silica fine particle to each toner mother particle were not performed.

[0207]

Table 2

[0208] <Production Example of Magnetic Carrier Core Particles 1> [Step 1 (Weighing and Mixing Step)] Fe2O₃ 68.3% by mass MnCO₃ 28.5% by mass Mg(OH)₂ 2.0% by mass SrCO₃ 1.2% by mass The above ferrite raw materials were weighed, and 20 parts by mass of water were added to 80 parts by mass of the ferrite raw materials. Then, a slurry was prepared by wet mixing for 3 hours using a 10 mm diameter zirconia ball mill. The solid content concentration of the slurry was 80% by mass.

[0209] [Process 2 (Calibration Process)] After drying the mixed slurry using a spray dryer (manufactured by Okawara Chemical Machinery Co., Ltd.), calcined ferrite was produced by firing it in a batch-type electric furnace under a nitrogen atmosphere (oxygen concentration 1.0 vol%) at a temperature of 1050°C for 3.0 hours.

[0210] [Process 3 (Grinding Process)] Calcined ferrite was crushed to approximately 0.5 mm using a crusher, and then water was added to prepare a slurry. The solid content concentration of the slurry was set to 70% by mass. This slurry was then ground for 3 hours in a wet ball mill using 1 / 8-inch stainless steel beads to obtain a slurry. This slurry was further ground for 4 hours in a wet bead mill using 1 mm diameter zirconia to obtain a calcined ferrite slurry with a volume-based 50% particle size (D50) of 1.3 μm.

[0211] [Process 4 (granulation process)] To 100 parts by mass of the above-mentioned calcined ferrite slurry, 1.0 part by mass of ammonium polycarboxylate was added as a dispersant and 1.5 parts by mass of polyvinyl alcohol was added as a binder. The mixture was then granulated into spherical particles using a spray dryer (manufactured by Okawara Chemical Machinery Co., Ltd.) and dried. After adjusting the particle size of the resulting granules, the mixture was heated in a rotary electric furnace at 700°C for 2 hours to remove organic matter such as dispersants and binders.

[0212] [Process 5 (Baking Process)] Under a nitrogen atmosphere (oxygen concentration 1.0 vol%), the temperature was raised from room temperature to the firing temperature (1100°C) in 2 hours, and then maintained at 1100°C for 4 hours for firing. After that, the temperature was lowered to 60°C over 8 hours, the atmosphere was changed from nitrogen to air, and the product was removed at a temperature of 40°C or lower.

[0213] [Process 6 (Sorting Process)] After crushing the aggregated particles, 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.

[0214] [Process 7 (filling process)] 100 parts by mass 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 dropwise were added a filling resin consisting of methyl silicone oligomer: 95.0% by mass and γ-aminopropyltrimethoxysilane: 5.0% by mass at atmospheric pressure while maintaining a temperature of 60°C.

[0215] 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.

[0216] The resin-filled magnetic core particles obtained after cooling were transferred to a mixer with spiral blades (Drum Mixer UD-AT type, manufactured by Sugiyama Heavy Industries Co., Ltd.) in a rotatable mixing container, and the temperature was raised to 140°C 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.

[0217] The ferrite particles were then cooled to room temperature, filled with resin, and hardened. Non-magnetic materials were removed using a magnetic separator. Coarse particles were then removed using a vibrating screen to obtain resin-filled magnetic carrier core particles 1.

[0218] [Examples of coating resin manufacturing] • Cyclohexyl methacrylate monomer 26.8% • Methyl methacrylate monomer 0.2% • Methyl methacrylate macromonomer 8.4% (A macromonomer with a weight-average molecular weight of 5000, having a methacryloyl group at one end.) • Toluene 31.3% • Methyl ethyl ketone 31.3% • Azobisisobutyronitrile 2.0% Among the above materials, cyclohexyl methacrylate monomer, methyl methacrylate monomer, methyl methacrylate macromonomer, toluene, and methyl ethyl ketone were placed in a four-neck separable flask equipped with a reflux condenser, thermometer, nitrogen inlet tube, and stirring device. After introducing nitrogen gas into the separable flask to create a sufficient nitrogen atmosphere, it was heated to 80°C, azobisisobutyronitrile was added, and it was refluxed for 5 hours for polymerization. Hexane was injected into the obtained reaction product to precipitate the copolymer, and after the obtained precipitate was filtered off, it was dried under vacuum to obtain a resin.

[0219] 30 parts by mass of the obtained resin was dissolved in a mixed solvent of 40 parts by mass of toluene and 30 parts by mass of methyl ethyl ketone to obtain a resin solution (solid content concentration: 30%).

[0220] [Preparation of Coating Resin Solution] · Resin solution (solid content concentration: 30%) 33.3% · Toluene 66.4% · Carbon black (Regal330; manufactured by Cabot Corporation) 0.3% [[ID=1-six]]](Number average particle diameter of primary particles: 25 nm, nitrogen adsorption specific surface area: 94 m 2 / g, DBP oil absorption: 75 ml / 100 g) [[ID= twenty]]The above materials were put into a paint shaker and dispersed for 1 hour using zirconia beads with a diameter of 0.5 mm. The obtained dispersion was filtered through a 5.0 μm membrane filter to obtain a coating resin solution.

[0221] <Production Example of Magnetic Carrier 1> The coating resin solution and the magnetic carrier core particles were put into a vacuum degassing kneader maintained at room temperature (the input amount of the coating resin solution was 2.5 parts by mass as a resin component with respect to 100 parts by mass of the magnetic carrier core particles 1).

[0222] <000097-five]] After the input, it was stirred at a rotation speed of 30 rpm for 15 minutes. After the solvent volatilized by a certain amount (80%) or more, the temperature was raised to 80°C while mixing under reduced pressure, and after distilling off toluene over 2 hours, it was cooled.

[0223] 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.

[0224] <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% • Methyl methacrylate monomer 8.6% • Toluene 31.3% • Methyl ethyl ketone 31.3% • Azobisisobutyronitrile 2.0%

[0225] <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% • Toluene 31.3% • Methyl ethyl ketone 31.3% • Azobisisobutyronitrile 2.0%

[0226] <Preparation of two-component developer> Using the combinations of toners 1-19 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.

[0227] [Table 3]

[0228] [Examples 1-18, Comparative Examples 1-3] The following evaluations were performed using the obtained two-component developers 1 to 21.

[0229] As the image forming apparatus, a modified Canon imageRUNNER ADVANCE C5560 digital commercial printer was used, with two-component developers placed in the cyan developer unit. The modifications to the apparatus included allowing free setting of the fixing temperature, process speed, DC voltage VDC of the developer carrier, charging voltage VD of the electrostatic latent image carrier, and laser power. For image output evaluation, a solid fill image (FFh image) with the desired aspect ratio was output, and the VDC, VD, and laser power were adjusted so that the amount of toner on the FFh image on the paper was as desired, and the evaluation described below was performed.

[0230] FFh is a hexadecimal value representing 256 gradations, where 00h is the first gradation (white area) of the 256 gradations, and FFh is the 256th gradation (solid area).

[0231] The evaluation was conducted based on the following evaluation method, and the results are shown in Table 4.

[0232] <Abrasion resistance> • Paper: Image Coat Gloss 158 (158.0g / m²) 2 ) (Sold by Canon Marketing Japan Inc.) • Toner amount on paper: 0.05 mg / cm² 2 (Image 2Fh) (Adjusted by the DC voltage VDC of the developer carrier, the charging voltage VD of the electrostatic latent image carrier, and the laser power) • Evaluation image: Place a 3cm x 15cm image in the center of the A4 paper shown above. • Fixation test environment: Normal temperature and humidity environment (temperature 23°C / humidity 50%RH (hereinafter N / N)) Fixing temperature: 160℃ • Process speed: 377 mm / sec The above evaluation images were output, and the abrasion resistance was assessed. The difference in reflectance was used as the evaluation index for abrasion resistance.

[0233] First, a JSPS-type friction fastness tester (AB-301: manufactured by Tester Sangyo Co., Ltd.) is used to apply a load of 0.5 kgf (4.9 N) to the image portion of the evaluation image, and friction (10 back-and-forth strokes) is performed with a new evaluation paper. Then, a reflectometer (REFLECTOMETER MODEL TC-6DS: manufactured by Tokyo Denshoku Co., Ltd.) is used to measure the reflectance of the friction-treated portion of the new evaluation paper and the reflectance of the un-friction-treated portion.

[0234] Then, the difference in reflectance before and after friction was calculated using the following formula. The obtained difference in reflectance was evaluated according to the following evaluation criteria. Difference in reflectance = Reflectance before friction - Reflectance after friction (Evaluation Criteria) AA: Less than 0.5% A: 0.5% or more and less than 1.0% B: 1.0% or more and less than 2.0% C: 2.0% or more and less than 4.0% D: 4.0% or more and less than 5.0% E: 5.0% or more

[0235] [Table 4]

Claims

1. A toner having toner particles containing a binder resin and ester wax, and silica fine particles A, 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 A is 60 nm or more and 500 nm or less. The silica fine particles A 29 In Si-NMR DD / MAS measurements, the Si in the structure represented by the following formula (1) a Peak PD1, which corresponds to the silicon atom shown, and Si in the structure represented by the following formula (2) b Peaks PD2 and SD2, corresponding to the silicon atoms shown, were observed, and when the areas of the peaks are denoted as SD1 and SD2, The area ratio of SD1 and SD2 is calculated, and the SP value (cal / mol) is calculated from the linear siloxane structure where the area ratio corresponds to the relative abundance of structural formulas (1) and (2). 1 / 2 And the SP value (cal / mol) of the ester wax. 1 / 2 The absolute value of the difference is 0.4 (cal / mol). 1 / 2 The following: The (SD1 + SD2) / SD1, calculated using the above SD1 and SD2, is between 3.0 and 7.

5. The toner is characterized in that the ester wax has a linear alkyl structure with 18 to 24 carbon atoms. 【Chemistry 1】

2. The toner according to claim 1, wherein the number-average particle size of the silica fine particles A is 80 nm or more and 200 nm or less.

Images