toner

Abstract

To provide a toner that maintains fluidity throughout its long life even in a high temperature and high humidity environment, prevents the occurrence of a harmful effect caused by aggregation of toner, further prevents the occurrence of a harmful effect caused by contamination of a conductive member, and can achieve the long life and high image quality.SOLUTION: A toner has a toner particle. An aggregate containing silica fine particles and a binding component is present on the surface of the toner particle, and the toner further has fatty acid metal salt particles. The arithmetic means value Ag of the Feret's diameter of the aggregates is 1000 nm or more and 8000 nm or less. When the number ratio of toner particles having the aggregates is defined as CI (number%), the CI is 1 number% or more and 15 number% or less. When the number ratio of toner particles having the aggregates in a toner after processing under an ultrasonic condition A is defined as Ca (number%) and the number ratio of toner particles having the aggregates in the toner after processing under an ultrasonic condition B as Cb (number%), the CI, the Ca, and the Cb satisfy the formulas (1) and (2). An ultrasonic condition A: an output frequency of 30 kHz, an output capacitance of 0.75 W, and an irradiation time of 300 s. An ultrasonic condition B: an output frequency of 30 kHz, an output capacitance of 25 W, and an irradiation time of 300 s. Formula (1) 0.90≤Ca / CI≤1.00. Formula (2) 0.10≤Cb / CI≤0.40.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a toner used in an image forming method such as an electrophotographic method.

Background Art

[0002] A method of visualizing image information through an electrostatic latent image such as an electrophotographic method is applied to a copying machine, a multifunction machine, and a printer. In recent years, with the diversification of usage purposes, further extension of the life and improvement of image quality of the electrophotographic main body and the toner cartridge have been demanded. In addition, in order to maintain high image quality throughout the life, it is effective to control so that the surface characteristics of the toner do not change throughout the life. In a normal electrophotographic process, the surface characteristics of the toner are controlled by disposing various organic or inorganic fine powders generally called external additives on the toner surface. Also, in order to provide stable images throughout the life in various regions around the world, it is necessary to maintain the characteristics as a toner in various environments. The external additive plays an important role in such toner design. Generally, silica is often used as the external additive, and silica imparts fluidity to the toner and plays an important role in the generation and maintenance of charges by triboelectrification. In addition to silica, various external additives such as titanium oxide and strontium titanate have been studied and used, and each gives the toner characteristics and features for printing a target image. There has also been a study on using the external additive as an aggregate instead of a single particle. For example, Patent Document 1 discloses a toner that can achieve high image quality even in a high-temperature and high-humidity environment by using an aggregate of silica. As described above, the external additive plays an important role in influencing the characteristics of the toner. However, in an electrophotographic printer with an extended life, it is difficult to maintain its characteristics throughout the life. The toner is mixed and rubbed during the printing process. In the case of a long-life printer, since this is repeated many times, the surface of the toner cannot maintain its initial state, and the external additive is embedded in or peeled off from the toner matrix, resulting in image defects appearing in the image. Various attempts have also been made regarding the durability of such toner. For example, in Patent Document 2, by having a certain amount of particles in which two or more silica particles with a primary particle size of 50 nm to 150 nm are aggregated, a toner is disclosed in which the embedding and detachment of the external additive are suppressed even in a high-speed machine.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] As described above, in order to achieve high image quality throughout a long life, toners having various external additives have been proposed so far. However, it is difficult to keep the state of the external additive unchanged from the initial stage to the latter half of the life in models with higher speed and longer life. Furthermore, in order to provide stable images in various environments, it is particularly necessary to cope with high-temperature and high-humidity environments. Under conditions with a large amount of moisture, toners tend to aggregate with each other and the fluidity becomes insufficient, which easily causes the toner to fuse to the developing blade. When the external additive and toner accumulate on the fused part, it will appear as streaks in the image (developing streaks). Increasing the amount of the external additive will lengthen the duration of its effect, but the adverse effects caused by the external additive contaminating the members will become prominent. For example, in the cleaning part, some of the external additive may pass through the cleaning part and contaminate the conductive member. When this phenomenon occurs, the entire conductive member will be sparsely contaminated, resulting in uneven potential on the photoreceptor and causing adverse effects such as uneven image density. These problems can become more prominent in long-life electrophotographic systems where the toner surface is continuously damaged and member contamination continues to accumulate. From this perspective, in the technologies described in Patent Document 1 and Patent Document 2, in a longer-life electrophotographic system, there was room for further improvement regarding maintaining the fluidity of the toner from the initial stage to the latter half of its life without change and regarding image defects associated with contamination of the conductive member. In view of these problems, the present disclosure provides a toner that can maintain fluidity throughout its long life, particularly even in a high-temperature and high-humidity environment, is less likely to cause image defects due to toner aggregation, and is also less likely to cause image defects resulting from contamination of the conductive member, thereby achieving long life and high image quality.

Means for Solving the Problems

[0005] The present invention relates to a toner having toner particles, agglomerates containing silica fine particles and a binder component are present on the surface of the toner particles, and further, the toner has fatty acid metal salt particles, the arithmetic mean value Ag of the Feret diameter of the agglomerates is 1000 nm or more and 8000 nm or less, and when the number ratio of the toner particles having the agglomerates is CI (number %), the CI is 1% or more and 15% or less, when the number ratio of the toner particles having the agglomerates in the toner after being treated under the following ultrasonic condition A is Ca (number %), and the number ratio of the toner particles having the agglomerates in the toner after being treated under the following ultrasonic condition B is Cb (number %), the present invention relates to a toner characterized in that the CI, the Ca, and the Cb satisfy formulas (1) and (2). · Ultrasonic condition A: Output frequency 30 kHz, output power 0.75 W, irradiation time 300 s · Ultrasonic condition B: Output frequency 30 kHz, output power 25 W, irradiation time 300 s 0.90 ≦ Ca / CI ≦ 1.00 Formula (1) 0.10 ≦ Cb / CI ≦ 0.40 Formula (2)

Advantages of the Invention

[0006] According to the present invention, even in a high-temperature and high-humidity environment, the toner maintains fluidity throughout its long life, making it less likely to cause image defects due to toner aggregation, and further less likely to cause image defects due to contamination of the conductive member, thereby providing a toner capable of achieving long life and high image quality.

Brief Description of the Drawings

[0007]

Figure 1

Figure 2

Figure 3

Figure 4

Modes for Carrying Out the Invention

[0008] In the present disclosure, the description of "XX or more and YY or less" or "XX to YY" representing a numerical range means a numerical range including the lower limit and the upper limit which are the endpoints, unless otherwise specified. When numerical ranges are described stepwise, the upper and lower limits of each numerical range can be arbitrarily combined. Further, in the following description, the toner particles before the presence of agglomerates on the surface of the toner particles may be referred to as "toner core particles".

[0009] 〔Features of the Present Invention〕 As described above, as an external additive for the toner, it is necessary to impart fluidity to the toner throughout its life and to assist in charging, and this ability is required even more strongly in a high-temperature and high-humidity environment where the toner is likely to aggregate.

[0010] As a means for stably imparting fluidity, it is conceivable to have a large amount of external additives present in the toner. The presence of a large amount of external additives increases the fluidity of the toner, and the necessary fluidity is maintained even in the latter half of the life and in a high-temperature and high-humidity environment.

[0011] However, the fact that there is a large amount of external additives means that the external additives are likely to migrate from the toner to the members, so it is easy to cause member contamination and it is also easy for the external additives to leak through in the cleaning section. Also, when the external additives are likely to migrate from the toner to the members, the external additives are consumed at an early stage, and it is difficult to maintain the effect throughout the long life.

[0012] Therefore, in order to maintain fluidity over a longer life and even in a high-temperature and high-humidity environment, it is necessary for the external additives necessary throughout the life to continue to exist on the toner surface without relying on a large amount of external additives, and to create a state where more external additives exist on the toner surface in a high-temperature and high-humidity environment.

[0013] In response to these required characteristics, the inventors have found that a toner having the following main configuration can maintain fluidity over a long life, suppress toner aggregation even in a high-temperature and high-humidity environment, hardly cause image defects, and provide high-quality electrophotographic images.

[0014] A toner having toner particles, Agglomerates containing silica fine particles and a binder component exist on the surface of the toner particles, and further, the toner has fatty acid metal salt particles, The arithmetic mean value Ag of the Feret diameter of the agglomerates is 1000 nm or more and 8000 nm or less, and when the number ratio of the toner particles having the agglomerates is CI (number %), the CI is 1 number % or more and 15 number % or less, When the number ratio of the toner particles having the agglomerates in the toner after being treated under the following ultrasonic condition A is Ca (number %), and the number ratio of the toner particles having the agglomerates in the toner after being treated under the following ultrasonic condition B is Cb (number %), The CI, the Ca, and the Cb satisfy formulas (1) and (2). · Ultrasonic condition A: output frequency 30 kHz, output power 0.75 W, irradiation time 300 s · Ultrasonic condition B: output frequency 30 kHz, output power 25 W, irradiation time 300 s 0.90 ≦ Ca / CI ≦ 1.00 Formula (1) 0.10 ≦ Cb / CI ≦ 0.40 Formula (2)

[0015] Regarding the mechanism by which the effect is achieved by the combination of the above agglomerates and the external additive, the inventors of the present invention have considered as follows.

[0016] In the toner of the present disclosure, agglomerates containing fatty acid metal salt particles and silica fine particles and a binder component are present on the surface of the toner particles. The fatty acid metal salt particles may be contained inside the agglomerates or may be present on the surface of the toner particles as an external additive. Since the agglomerates have constituent components represented by silica fine particles or a binder component that connects the toner particles and the agglomerates, unlike ordinary aggregates of silica fine particles, the constituent components represented by silica fine particles and the toner particles and the agglomerates are in a state where they are difficult to separate.

[0017] Further, in the toner of the present disclosure, when the percentage of the number of toner particles having the agglomerates is defined as CI (number %), the CI is 1% or more and 15% or less by number. When the toner is treated under the above ultrasonic condition A, the percentage of the number of toner particles having the agglomerates is defined as Ca (number %), and when the toner is treated under the above ultrasonic condition B, the percentage of the number of toner particles having the agglomerates is defined as Cb, the CI, the Ca, and the Cb 0.90 ≦ Ca / CI ≦ 1.00 Formula (1) 0.10 ≦ Cb / CI ≦ 0.40 Formula (2) satisfy the following.

[0018] That is, when the applied energy is weak, the toner does not break away and detach, and when the applied energy is high, it breaks away and detaches. Since the applied energy accumulates, it indicates that if it is agitated for a long time, it will gradually break away and detach. That is, at the initial stage of the life, the energy due to agitation and friction applied to the agglomerates is weak, so the agglomerates do not detach. Therefore, the harmful effects of member contamination due to excessive supply of external additives as described above do not occur. As printing continues and the energy due to agitation and friction applied to the agglomerates accumulates, the agglomerates break away from the toner. Since the main component of the detached agglomerates is an external additive component such as silica fine particles, the detached ones adhere to the surface of the toner particles as an external additive and give fluidity to the toner as a fresh external additive. By such an action, the external additive is sequentially supplied from the agglomerates throughout the life, so that image defects can be suppressed even in the latter half of the life.

[0019] Furthermore, the presence of fatty acid metal salt particles gives this action environmental responsiveness. Fatty acid metal salt particles are lubricants and have a strong hydrophobic action. Fatty acid metal salt particles in contact with the agglomerates will have a repulsive force with the surrounding components in an environment with a high moisture content at high temperature and high humidity, so that they will have a repulsive force with the surrounding components, and their lubricant properties will also be added, becoming the starting point for the agglomerates to break when energy is applied. By this action, the agglomerates containing fatty acid metal salt particles are promoted to detach from the toner in a high temperature and high humidity environment, and a large amount is supplied to the toner as an external additive. It is presumed that this can suppress the aggregation of the toner and maintain its fluidity even in a state of excessive moisture, and can suppress image defects such as developing streaks due to toner fusion.

[0020] Hereinafter, based on the above mechanism, including the preferred range of the present invention, the details will be described.

[0021] 〔Fatty Acid Metal Salt Particles, Agglomerates, and Toner Particles〕 The toner of the present invention contains fatty acid metal salt particles. The metal of the fatty acid metal salt particles is preferably a polyvalent metal of divalent or higher, and a salt of at least one metal selected from the group consisting of zinc, calcium, magnesium, aluminum, and lithium is preferred. In terms of further improving the cleaning characteristics in an extremely low temperature and low humidity environment, the central metal of the fatty acid metal salt is preferably zinc.

[0022] Further, as the fatty acid of the fatty acid metal salt particles, a higher fatty acid having 8 to 28 carbon atoms (more preferably 12 to 22 carbon atoms) is preferred. That is, the fatty acid metal salt particles are preferably a fatty acid metal salt of a polyvalent metal of divalent or higher (more preferably divalent or trivalent, still more preferably divalent) and a fatty acid having 8 to 28 carbon atoms (more preferably 12 to 22 carbon atoms). When a fatty acid having 8 or more carbon atoms is used, it is easy to suppress the generation of free fatty acids. The amount of free fatty acids is preferably 0.20% by mass or less. If the carbon number of the fatty acid is 28 or less, the melting point of the fatty acid metal salt particles does not become too high, and it is difficult to inhibit the fixing property. As the fatty acid, stearic acid is particularly preferred. The polyvalent metal of divalent or higher preferably contains zinc.

[0023] Examples of the fatty acid metal salt particles include metal stearates such as zinc stearate, calcium stearate, magnesium stearate, aluminum stearate, and lithium stearate, and zinc laurate.

[0024] Further, the fatty acid metal salt particles are preferably contained in the toner in an amount of 0.1% by mass or more and 3.0% by mass or less. More preferably, it is 0.2% by mass or more and 2.0% by mass or less. If the amount of the fatty acid metal salt is too small, the effect of the present disclosure corresponding to an environment with a large amount of moisture cannot be obtained. If the amount of the fatty acid metal salt is too large, the contamination of the member will be deteriorated.

[0025] In addition, the form of containing the fatty acid metal salt particles in the toner of the present invention may be either contained inside the agglomerate or present on the surface of the toner particles, or may be added separately as an external additive together with the inside of the agglomerate.

[0026] FIG. 1 is a representative view of toner in which agglomerates are present on the surface of toner particles.

[0027] Examples of the agglomerates containing silica fine particles and a binder component include particles mainly composed of silica and a binder component capable of binding these particles together.

[0028] Examples of the particles mainly composed of silica include so-called dry silica fine particles (hereinafter also referred to as fumed silica) produced by vapor phase oxidation of silicon halides, and so-called wet silica fine particles (hereinafter also referred to as colloidal silica) produced from water glass and the like. Both of these particles may be subjected to a hydrophobization treatment. Examples of the treatment agent used for the hydrophobization treatment include silicone varnishes, various modified silicone varnishes, silicone oils, various modified silicone oils, silane compounds, silane coupling agents, other organosilicon compounds, and organotitanium compounds. These may be used alone or in combination of two or more.

[0029] The silica fine particles preferably have a number average particle diameter of primary particles of 10 nm or more and 200 nm or less (more preferably 15 nm or more and 150 nm or less). The number average particle diameter of the primary particles of the silica fine particles is preferably measured using a photograph of the toner taken at an enlarged scale by a scanning electron microscope.

[0030] In addition, the agglomerates may contain, in addition to the silica fine particles, external additives generally used in electrophotographic toners, titanium oxide particles, strontium titanate particles, alumina particles, fatty acid metal salt particles, and the like.

[0031] Particularly preferably, the agglomerates contain fatty acid metal salt particles, and on the surface observed by a scanning electron microscope, the area ratio of the fatty acid metal salt particles in the agglomerates is preferably 2% or more and 30% or less with respect to the entire agglomerates.

[0032] As a binding component capable of binding silica fine particles, one that can fix the particles with appropriate strength and cause no adverse effects even when subjected to environmental changes such as mechanical stress, temperature, and humidity in the development process is required. Examples of such materials include organic resins. In particular, vinyl resins and polyester resins can be preferably used. These can hold the silica fine particles with appropriate fixing strength, and as the toner is used, it becomes possible to continuously supply the silica fine particles into the development process. Also, although the binding component itself is simultaneously supplied into the development process, by appropriately selecting the responsiveness of the binding component to environmental changes such as hardness, temperature, and humidity, member contamination and changes in development characteristics can be suppressed. Specific materials will be described in the section on the manufacturing method described later.

[0033] In the toner of the present invention, when the number ratio of toner particles having the agglomerates is defined as CI (number %), it is necessary that the CI is 1% by number or more and 15% by number or less. If the CI is too low, the number of agglomerates contained is too small, and thus the effects of the present disclosure cannot be obtained. If the CI is too high, the number of agglomerates contained is too large, which deteriorates the contamination of the conductive member. The CI is preferably 2% by number or more and 14% by number or less, and more preferably 3% by number or more and 12% by number or less. Also, the CI can be controlled by adjusting manufacturing conditions such as the number of charged parts of the material, the material type, and stirring conditions.

[0034] Furthermore, in the toner of the present invention, when the number ratio of toner particles having the agglomerates in the toner after being treated under the following ultrasonic condition A is defined as Ca (number %), and the number ratio of toner particles having the agglomerates in the toner after being treated under the following ultrasonic condition B is defined as Cb (number %), it is necessary that the above CI, the Ca, and the Cb satisfy the relationships of formulas (1) and (2). · Ultrasonic condition A: Output frequency 30 kHz, output capacity 0.75 W, irradiation time 300 s · Ultrasonic condition B: Output frequency 30 kHz, output capacity 25 W, irradiation time 300 s 0.90 ≦ Ca / CI ≦ 1.00 Formula (1) 0.10 ≦ Cb / CI ≦ 0.40 Formula (2)

[0035] That is, the range of Ca / CI needs to be 0.90 or more and 1.00 or less. When Ca / CI is less than 0.90, it means that even in the case of a weak share of agglomerates, they are likely to detach. For this reason, the agglomerates are consumed immediately, the effect does not last long, and the conductive member is also easily contaminated. The preferable range of Ca / CI is 0.95 or more and 1.00 or less. Ca / CI can be controlled by adjusting the material types of silica fine particles and binder components, and their respective compounding ratios, etc.

[0036] The range of Cb / CI needs to be 0.10 or more and 0.40 or less. When Cb / CI is greater than 0.40, it means that it is difficult for the agglomerates to detach even in the case of a high share, so the effect of the present disclosure is difficult to obtain. The preferable range of Cb / CI is 0.10 or more and 0.38 or less. Cb / CI can be controlled by adjusting the material types of silica fine particles and binder components, and their respective compounding ratios, etc.

[0037] Furthermore, it is necessary that the arithmetic mean value Ag of the Feret diameter of the agglomerates is 1000 nm or more and 8000 nm or less. If the agglomerates are within the above range, since the agglomerates are large enough, the supply of the toner with agglomerates to the developing unit is delayed, and they are stirred in the container for a longer time, so the chance for the agglomerates to detach is likely to be obtained. Preferably it is 1300 nm or more and 7500 nm or less, and more preferably 1500 nm or more and 7000 nm or less. The arithmetic mean value Ag of the Feret diameter of the agglomerates can be controlled by adjusting manufacturing conditions such as the particle size of the silica fine particles used, the number of charged parts, the compounding ratio of the silica fine particles and the binder component, and the stirring conditions.

[0038] Furthermore, on the surface of toner particles having such agglomerates observed with a scanning electron microscope, it is preferable that the area ratio of the binding component of the agglomerates is 5% or more and 50% or less with respect to the entire agglomerate. As described above, by appropriately containing the binding component in the agglomerates, the detachment of the agglomerates from the toner is appropriately controlled, and the effects of the present disclosure can be obtained at a high level. If it is smaller than this range, the agglomerates are likely to detach, easily contaminate the conductive member, and it is difficult to obtain the effects over a long life. If it is larger than this range, the agglomerates are difficult to detach, and it is difficult to obtain the effect of continuous fluidity improvement. The area ratio of the binding component of the agglomerates can be controlled by adjusting production conditions such as the blending ratio of the silica fine particles and the binding component, and the stirring conditions.

[0039] Furthermore, among the toner particles having such agglomerates, it is preferable to contain 50% by number or more of toner particles having agglomerates satisfying the following (a). (a) In an image obtained by binarizing a reflected electron image of an agglomerate photographed with a scanning electron microscope, with the midpoint of the image of the agglomerate as a reference point, when 18 straight lines are drawn at 10° intervals passing through the reference point, the number A of straight lines having a line segment with a continuous dark part length of 100 nm or more on the straight line is 12 or more with respect to the total 18 straight lines.

[0040] Satisfying the above (a) means that the binding component is evenly dispersed in the agglomerate. Therefore, variation in the migration of the agglomerates hardly occurs, and the effects of the present disclosure can be easily obtained. Preferably it is 60% by number or more, more preferably 80% by number or more.

[0041] As a means for controlling the number of toner particles having agglomerates satisfying the above (a), it can be controlled by adjusting production conditions such as the blending ratio of the silica fine particles and the binding component, and the dispersion conditions of the silica fine particles and the binding component used.

[0042] In addition, when the dispersion liquid obtained by treating the toner under the above ultrasonic condition A is measured with a flow-type particle image measuring device, the presence ratio YA (number %) of particles smaller than 4 μm is preferably 20% or more and 50% or less. The main component of these fine particles is an agglomerate detached from the toner. By appropriately existing from the initial stage of the life, it gives the toner appropriate fluidity and suppresses image defects. If the amount is too small, the effect cannot be exerted, and if it is too large, the harm of member contamination appears.

[0043] As a means for controlling the presence ratio YA (number %) of particles smaller than 4 μm, it can be controlled by adjusting manufacturing conditions such as the blending ratio of silica fine particles and the binder component, and the dispersion conditions of the silica fine particles and the binder component used.

[0044] 〔Constituent components of toner particles other than agglomerates〕 <Binder resin> The toner particles contain a binder resin. The content of the binder resin is preferably 50% by mass or more based on the total amount of the resin components in the toner particles.

[0045] The binder resin is not particularly limited, and examples thereof include styrene acrylic resin, epoxy resin, polyester resin, polyurethane resin, polyamide resin, cellulose resin, polyether resin, mixed resins and composite resins thereof. Styrene acrylic resin and polyester resin are preferable in terms of low cost, easy availability and excellent low-temperature fixability.

[0046] Examples of the styrene acrylic resin include polymers composed of the following monofunctional polymerizable monomers or polyfunctional polymerizable monomers, copolymers obtained by combining two or more of them, and mixtures thereof.

[0047] Examples of the monofunctional polymerizable monomers include the following.

[0048] Styrene; styrene derivatives such as α-methylstyrene, β-methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, 2,4-dimethylstyrene, p-n-butylstyrene, p-tert-butylstyrene, p-n-hexylstyrene, p-n-octylstyrene, p-n-nonylstyrene, p-n-decylstyrene, p-n-dodecylstyrene, p-methoxystyrene, p-phenylstyrene; acrylic polymerizable monomers such as methyl acrylate, ethyl acrylate, n-propyl acrylate, iso-propyl acrylate, n-butyl acrylate, iso-butyl acrylate, tert-butyl acrylate, n-amyl acrylate, n-hexyl acrylate, 2-ethylhexyl acrylate, n-octyl acrylate, n-nonyl acrylate, cyclohexyl acrylate, benzyl acrylate, ethyl acrylate dimethyl phosphate, ethyl acrylate diethyl phosphate, ethyl acrylate dibutyl phosphate, 2-benzoyloxyethyl acrylate; methacrylic polymerizable monomers such as methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, iso-propyl methacrylate, n-butyl methacrylate, iso-butyl methacrylate, tert-butyl methacrylate, n-amyl methacrylate, n-hexyl methacrylate, 2-ethylhexyl methacrylate, n-octyl methacrylate, n-nonyl methacrylate, ethyl methacrylate diethyl phosphate, ethyl methacrylate dibutyl phosphate; methylene aliphatic monocarboxylic acid esters; vinyl esters such as vinyl acetate, vinyl propionate, vinyl butyrate, vinyl benzoate, vinyl formate; vinyl ethers such as vinyl methyl ether, vinyl ethyl ether, vinyl isobutyl ether; vinyl ketones such as vinyl methyl ketone, vinyl hexyl ketone, vinyl isopropyl ketone.

[0049] Examples of the polyfunctional polymerizable monomers include the following.

[0050] Diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol diacrylate, 1,6 - hexanediol diacrylate, neopentyl glycol diacrylate, tripropylene glycol diacrylate, polypropylene glycol diacrylate, 2,2’ - bis(4 - (acryloxy·diethoxy)phenyl)propane, trimethylolpropane triacrylate, pentaerythritol tetraacrylate, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, 1,3 - butylene glycol dimethacrylate, 1,6 - hexanediol dimethacrylate, neopentyl glycol dimethacrylate, polypropylene glycol dimethacrylate, 2,2’ - bis(4 - (methacryloxy·diethoxy)phenyl)propane, 2,2’ - bis(4 - (methacryloxy·polyethoxy)phenyl)propane, trimethylolpropane trimethacrylate, pentaerythritol tetramethacrylate, divinylbenzene, divinylnaphthalene, divinyl ether, etc.

[0051] As the polyester resin, those obtained by condensation polymerization of the following carboxylic acid component and alcohol component can be used. Examples of the carboxylic acid component include terephthalic acid, isophthalic acid, phthalic acid, fumaric acid, maleic acid, cyclohexanedicarboxylic acid, and trimellitic acid. Examples of the alcohol component include bisphenol A, hydrogenated bisphenol, ethylene oxide adduct of bisphenol A, propylene oxide adduct of bisphenol A, glycerin, trimethylolpropane, and pentaerythritol.

[0052] Also, the polyester resin may be a polyester resin containing a urea group. It is preferable not to cap the carboxy groups such as at the terminals as the polyester resin.

[0053] <Colorant, magnetic material> The toner particles may contain a colorant. As the colorant, known pigments and dyes can be used. From the viewpoint of excellent weather resistance, a pigment is preferred as the colorant.

[0054] Examples of cyan-based colorants include copper phthalocyanine compounds and their derivatives, anthraquinone compounds, and basic dye lake compounds.

[0055] Specifically, the following can be mentioned. C.I. Pigment Blue 1, 7, 15, 15:1, 15:2, 15:3, 15:4, 60, 62, and 66.

[0056] Examples of magenta-based colorants include condensed azo compounds, diketopyrrolopyrrole compounds, anthraquinone compounds, quinacridone compounds, basic dye lake compounds, naphthol compounds, benzimidazolone compounds, thioindigo compounds, and perylene compounds.

[0057] Specifically, the following can be mentioned. C.I. Pigment Red 2, 3, 5, 6, 7, 23, 48:2, 48:3, 48:4, 57:1, 81:1, 122, 144, 146, 150, 166, 169, 177, 184, 185, 202, 206, 220, 221, and 254, and C.I. Pigment Violet 19.

[0058] Examples of yellow-based colorants include condensed azo compounds, isoindolinone compounds, anthraquinone compounds, azo metal complexes, methine compounds, and allylamide compounds.

[0059] Specifically, the following can be mentioned. C.I. Pigment Yellow 12, 13, 14, 15, 17, 62, 74, 83, 93, 94, 95, 97, 109, 110, 111, 120, 127, 128, 129, 147, 151, 154, 155, 168, 174, 175, 176, 180, 181, 185, 191, and 194.

[0060] Examples of the black colorant include carbon black and those toned to black using the above yellow, magenta, and cyan colorants.

[0061] These colorants can be used alone, as a mixture, or even in a solid solution state.

[0062] It is preferable to use the colorant in an amount of 1.0 to 20.0 parts by mass based on 100.0 parts by mass of the binder resin.

[0063] The toner can also contain a magnetic material to form a magnetic toner. In this case, the magnetic material can also serve as a colorant.

[0064] Examples of the magnetic material include iron oxides typified by magnetite, hematite, and ferrite; metals typified by iron, cobalt, and nickel; or alloys and mixtures thereof with metals such as aluminum, cobalt, copper, lead, magnesium, tin, zinc, antimony, beryllium, bismuth, cadmium, calcium, manganese, selenium, titanium, tungsten, and vanadium.

[0065] <Release agent> The toner particles may contain a release agent. As the release agent, conventionally known waxes may be used without particular limitation. Specifically, the following are examples.

[0066] Petroleum waxes typified by paraffin wax, microcrystalline wax, and petrolactam and their derivatives; montan wax and its derivatives; hydrocarbon waxes obtained by the Fischer-Tropsch method and their derivatives; polyolefin waxes typified by polyethylene and their derivatives; natural waxes typified by carnauba wax and candelilla wax and their derivatives.

[0067] The derivatives include oxides, block copolymers with vinyl monomers, and graft-modified products.

[0068] Also, alcohols such as higher aliphatic alcohols; fatty acids such as stearic acid and palmitic acid, or their acid amides, esters, and ketones; hydrogenated castor oil and its derivatives, vegetable waxes, and animal waxes. These can be used alone or in combination.

[0069] Among these, when polyolefins, hydrocarbon waxes obtained by the Fischer-Tropsch process, and petroleum waxes are used, the developability and transferability tend to improve, which is preferable.

[0070] In addition, antioxidants may be added to these waxes as long as the above effects are not affected.

[0071] The content of the release agent is preferably 1.0 part by mass or more and 30.0 parts by mass or less with respect to 100.0 parts by mass of the binder resin or the polymerizable monomer forming the binder resin.

[0072] The melting point of the release agent is preferably 30°C or higher and 120°C or lower, more preferably 60°C or higher and 100°C or lower.

[0073] By using a release agent having the above heat characteristics, the release effect is efficiently exhibited, and a wider fixing area is ensured.

[0074] 〔External Additive〕 Various organic or inorganic fine powders may be added to the toner particles as necessary within the range that does not impair the effects of this case. The organic or inorganic fine powder preferably has a particle size of 1 / 10 or less of the weight average particle size of the toner particles in terms of durability when added to the toner particles.

[0075] As the organic or inorganic fine powder, for example, the following are used. (1) Fluidity-imparting agents: silica, alumina, titanium oxide, carbon black, and fluorinated carbon. (2) Abrasive: Metal oxides (e.g., strontium titanate, cerium oxide, alumina, magnesium oxide, chromium oxide), nitrides (e.g., silicon nitride), carbides (e.g., silicon carbide), metal salts (e.g., calcium sulfate, barium sulfate, calcium carbonate). (3) Lubricant: Fluorine-based resin powder (e.g., vinylidene fluoride, polytetrafluoroethylene), fatty acid metal salts (e.g., zinc stearate, calcium stearate). (4) Charge control particles: Metal oxides (e.g., tin oxide, titanium oxide, zinc oxide, silica, alumina), carbon black, hydrotalcite.

[0076] The organic or inorganic fine powder may have its surface hydrophobized for improving the fluidity of the toner and equalizing the charging of toner particles. Examples of the treating agent for hydrophobizing the organic or inorganic fine powder include unmodified silicone varnish, various modified silicone varnishes, unmodified silicone oil, various modified silicone oils, silane compounds, silane coupling agents, other organosilicon compounds, and organic titanium compounds. These treating agents may be used alone or in combination.

[0077] Among them, it is preferable to contain silicone resin fine particles as an external additive. Due to its elasticity, the silicone resin fine particles are difficult to be embedded in the toner surface and have high durability. Since the agglomerates detached from the toner are no different from ordinary external additives, the durability of detachment is also improved by their coexistence with the silicone resin fine particles, so it is highly effective in suppressing adverse effects over a longer life.

[0078] 〔Method for manufacturing toner〕 Hereinafter, an example of the method for obtaining the above toner particles will be described, but it is not limited to the following.

[0079] The method for manufacturing toner particles is not particularly limited, and suspension polymerization method, dissolution suspension method, emulsion aggregation method, pulverization method, etc. can be used. As an example, the method for obtaining toner particles by the emulsion aggregation method will be described below.

[0080] <Method for manufacturing toner particles (toner core particles) by emulsion aggregation method> (Preparation process of resin fine particle dispersion liquid) The resin fine particle dispersion liquid can be prepared by known methods, but is not limited to these methods. For example, emulsion polymerization method, self-emulsification method, phase inversion emulsification method in which an aqueous medium is added to a resin solution dissolved in an organic solvent to emulsify the resin, or forced emulsification method in which the resin is forcibly emulsified by heat treatment in an aqueous medium without using an organic solvent can be mentioned.

[0081] As an example, the method for preparing a resin fine particle dispersion liquid by the phase inversion emulsification method will be described below.

[0082] Dissolve the resin component in an organic solvent in which these are soluble, and add a surfactant or a basic compound. In that case, if the resin component is a crystalline resin having a melting point, it may be heated to a temperature above the melting point and dissolved. Subsequently, while stirring with a homogenizer or the like, an aqueous medium is slowly added to precipitate resin fine particles. Then, the solvent is removed by heating or reduced pressure to prepare an aqueous dispersion liquid of resin fine particles.

[0083] Here, the organic solvent used for dissolving the resin component may be any one that can dissolve these. Specifically, toluene, xylene, etc. can be mentioned.

[0084] Examples of the surfactant used in the preparation process include anionic surfactants such as sulfate ester salts, sulfonate salts, carboxylate salts, phosphate esters, and soaps; cationic surfactants such as amine salts and quaternary ammonium salts; and non-ionic surfactants such as polyethylene glycols, alkylphenol ethylene oxide adducts, and polyhydric alcohols.

[0085] Examples of the basic compound used in the preparation process include inorganic bases such as sodium hydroxide and potassium hydroxide; and organic bases such as ammonia, triethylamine, trimethylamine, dimethylaminoethanol, and diethylaminoethanol. The basic compound may be used alone or in combination of two or more kinds.

[0086] (Preparation of Colorant Dispersion Liquid) For the preparation of the colorant dispersion liquid, known dispersion methods can be used. For example, general dispersion means such as a homogenizer, a ball mill, a colloid mill, and an ultrasonic disperser can be used, and there is no particular limitation. Examples of the surfactant used during dispersion include the surfactants described above.

[0087] (Preparation of Wax Dispersion Liquid) In the preparation of the wax dispersion liquid, the wax is dispersed in water together with a surfactant, a basic compound, etc., and then heated to a temperature equal to or higher than the melting point of the wax, and dispersion treatment is performed using a homogenizer or a disperser that applies a strong shearing force. By undergoing such treatment, a wax dispersion liquid can be obtained. Examples of the surfactant used during dispersion include the surfactants described above. Examples of the basic compound used during dispersion include the basic compounds described above.

[0088] (Agglomerated Particle Formation Step) In the agglomerated particle formation step, first, a resin fine particle dispersion liquid, a colorant dispersion liquid, a wax dispersion liquid, etc. are mixed to obtain a mixed liquid. Next, while heating at a temperature equal to or lower than the melting point of the resin fine particles, the pH is made acidic to cause agglomeration, and agglomerated particles containing resin fine particles, colorant particles, and release agent particles are formed to obtain an agglomerated particle dispersion liquid.

[0089] (First Fusion Step) In the first fusion step, under stirring conditions similar to those in the agglomerated particle formation step, the pH of the agglomerated particle dispersion liquid is increased to stop the progress of agglomeration, and heating is performed at a temperature equal to or higher than the melting point of the resin component to obtain a fused particle dispersion liquid.

[0090] (Amorphous Resin Fine Particle Attachment Step) In the amorphous resin fine particle attachment step, an amorphous resin fine particle dispersion liquid is added to the fused particle dispersion liquid, and the pH is decreased, so that amorphous resin particles are attached to the surface of the fused particles to obtain a dispersion liquid of resin-attached particles. Here, this coating layer corresponds to the shell layer formed through the shell layer formation step described later. Note that the amorphous resin fine particle dispersion liquid can be manufactured according to the preparation step of the resin fine particle dispersion liquid described above.

[0091] (Second Fusion Step) In the second fusion step, in accordance with the first fusion step, the progress of aggregation is stopped by increasing the pH of the resin-attached particle dispersion liquid, and the resin-attached aggregated particles are fused by heating at a temperature equal to or higher than the melting point of the resin component to obtain a toner core particle dispersion liquid in which toner core particles with a shell layer formed thereon are dispersed.

[0092] <Method for Manufacturing Toner Having Agglomerates>[ As a method for manufacturing toner particles having agglomerates containing silica fine particles and a binder component, from the viewpoint of uniformly aggregating the silica fine particles and the binder component, it is preferable to externally add them to the toner core particles in a wet manner. When obtaining a toner having agglomerates containing silica fine particles and a binder component in a wet manner, (Step 1) A step of obtaining a toner core particle dispersion liquid in which toner core particles are dispersed in an aqueous medium and (Step 2) A step of mixing silica fine particles and a polymerizable monomer (monomer) serving as a binder resin component into the toner core particle dispersion liquid, and forming agglomerates having silica fine particles and a binder resin on the toner core particles by polymerizing the monomer in the toner core particle dispersion liquid are preferably included.

[0093] In Step 1, examples of the method for obtaining the toner core particle dispersion liquid include a method of directly using a dispersion liquid of toner core particles manufactured in an aqueous medium, and a method of charging dry toner core particles into an aqueous medium and mechanically dispersing them. When dispersing dry toner core particles in an aqueous medium, a dispersion aid may be used.

[0094] As the dispersion aid, known dispersion stabilizers, surfactants, etc. can be used.

[0095] Specifically, the following can be mentioned as dispersion stabilizers.

[0096] Inorganic dispersion stabilizers such as tricalcium phosphate, hydroxyapatite, magnesium phosphate, zinc phosphate, aluminum phosphate, calcium carbonate, magnesium carbonate, calcium hydroxide, magnesium hydroxide, aluminum hydroxide, calcium metasilicate, calcium sulfate, barium sulfate, bentonite, silica, alumina; organic dispersion stabilizers such as polyvinyl alcohol, gelatin, methyl cellulose, methyl hydroxypropyl cellulose, ethyl cellulose, sodium salt of carboxymethyl cellulose, starch.

[0097] Also, the following can be mentioned as surfactants. Anionic surfactants such as alkyl sulfate esters, alkylbenzene sulfonates, fatty acid salts; nonionic surfactants such as polyoxyethylene alkyl ethers, polyoxypropylene alkyl ethers; cationic surfactants such as alkylamine salts, quaternary ammonium salts.

[0098] In step 1, it is preferable to adjust the solid content concentration of the toner core particle dispersion to 10 mass% or more and 50 mass% or less.

[0099] In step 2, the silica fine particles and the monomer serving as the binder component may be added directly to the toner core particle dispersion, or a dispersion in which the silica fine particles and the monomer are previously dispersed may be added to the toner core particle dispersion. As the means for dispersing the silica fine particles and the monomer, the dispersion aids exemplified in the section of step 1 can be used. Also, when mixing particles such as fatty acid metal salts in addition to the silica fine particles, they are mixed together with the silica fine particles in step 2.

[0100] Examples of the binding component include polymers composed of monofunctional polymerizable monomers or polyfunctional polymerizable monomers, copolymers obtained by combining two or more of these, and mixtures thereof.

[0101] Examples of the polymerizable monomer include, for example, the following.

[0102] Styrene; styrene derivatives such as α-methylstyrene, β-methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, 2,4-dimethylstyrene, p-n-butylstyrene, p-tert-butylstyrene, p-n-hexylstyrene, p-n-octylstyrene, p-n-nonylstyrene, p-n-decylstyrene, p-n-dodecylstyrene, p-methoxystyrene, p-phenylstyrene; acrylic polymerizable monomers such as methyl acrylate, ethyl acrylate, n-propyl acrylate, iso-propyl acrylate, n-butyl acrylate, iso-butyl acrylate, tert-butyl acrylate, n-amyl acrylate, n-hexyl acrylate, 2-ethylhexyl acrylate, n-octyl acrylate, n-nonyl acrylate, cyclohexyl acrylate, benzyl acrylate, ethyl acrylate dimethyl phosphate, ethyl acrylate diethyl phosphate, ethyl acrylate dibutyl phosphate, 2-benzoyloxyethyl acrylate; methacrylic polymerizable monomers such as methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, iso-propyl methacrylate, n-butyl methacrylate, iso-butyl methacrylate, tert-butyl methacrylate, n-amyl methacrylate, n-hexyl methacrylate, 2-ethylhexyl methacrylate, n-octyl methacrylate, n-nonyl methacrylate, ethyl methacrylate diethyl phosphate, ethyl methacrylate dibutyl phosphate; methylene aliphatic monocarboxylic acid esters; vinyl esters such as vinyl acetate, vinyl propionate, vinyl butyrate, vinyl benzoate, vinyl formate; vinyl ethers such as vinyl methyl ether, vinyl ethyl ether, vinyl isobutyl ether; vinyl ketones such as vinyl methyl ketone, vinyl hexyl ketone, vinyl isopropyl ketone; trifunctional silane compounds having a methacryloxyalkyl group as a substituent such as γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropyltriethoxysilane, γ-methacryloxyoctyltrimethoxysilane, γ-methacryloxypropyldiethoxymethoxysilane, γ-methacryloxypropylethoxydimethoxysilane; Trifunctional silane compounds having an acryloxyalkyl group as a substituent, such as γ-acryloxypropyltrimethoxysilane, γ-acryloxypropyltriethoxysilane, γ-acryloxyoctyltrimethoxysilane, γ-acryloxypropyldiethoxymethoxysilane, γ-acryloxypropylethoxydimethoxysilane, etc.

[0103] Among them, from the viewpoint of high affinity with silica, it is preferable to use a trifunctional silane compound. Further, the following may be used in combination with the trifunctional silane compound. An organosilicon compound having four reactive groups in one molecule (tetrafunctional silane), an organosilicon compound having two reactive groups in one molecule (bifunctional silane), or an organosilicon compound having one reactive group (monofunctional silane). For example, the following can be mentioned.

[0104] Trifunctional vinylsilanes such as dimethyldiethoxysilane, tetraethoxysilane, hexamethyldisilazane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-(2-aminoethyl)aminopropyltrimethoxysilane, 3-(2-aminoethyl)aminopropyltriethoxysilane, vinyltriisocyanatosilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyldiethoxymethoxysilane, vinylethoxydimethoxysilane, vinylethoxydihydroxysilane, vinyldimethoxyhydroxysilane, vinylethoxymethoxyhydroxysilane, vinyldiethoxyhydroxysilane.

[0105] In Step 2, silica fine particles and a monomer as a binder component are added to and mixed with the toner core particle dispersion. At this time, it is preferable to adjust the temperature of the toner core particle dispersion to a temperature suitable for the polymerization reaction. Then, while mixing the toner core particles, the silica fine particles, and the monomer, a polymerization initiator is added to polymerize the added monomer, and aggregates containing the silica fine particles and the binder component are externally added to the toner core particles to obtain a dispersion of toner particles.

[0106] As the polymerization initiator, known polymerization initiators can be used without particular limitation. Specifically, the following can be mentioned.

[0107] Hydrogen peroxide, acetyl peroxide, cumyl peroxide, tert-butyl peroxide, propionyl peroxide, benzoyl peroxide, chlorobenzoyl peroxide, dichlorobenzoyl peroxide, bromomethylbenzoyl peroxide, lauroyl peroxide, ammonium persulfate, sodium persulfate, potassium persulfate, diisopropyl peroxydicarbonate, tetralin hydroperoxide, 1-phenyl-2-methylpropyl-1-hydroperoxide, tert-hydroperoxide of pertrityl acetate, tert-butyl peroxyformate, tert-butyl peracetate, tert-butyl perbenzoate, tert-butyl perphenylacetate, tert-butyl permethoxyacetate, tert-butyl N-(3-toluoyl)palmitate benzoyl peroxide, t-butyl peroxy 2-ethylhexanoate, t-butyl peroxypivalate, t-butyl peroxyisobutyrate, t-butyl peroxyneodecanoate, methyl ethyl ketone peroxide, diisopropyl peroxydicarbonate, cumene hydroperoxide, 2,4-dichlorobenzoyl peroxide, lauroyl peroxide and other peroxide-based polymerization initiators; 2,2'-azobis-(2,4-dimethylvaleronitrile), 2,2'-azobisisobutyronitrile, 1,1'-azobis(cyclohexane-1-carbonitrile), 2,2'-azobis-4-methoxy-2,4-dimethylvaleronitrile, azobisisobutyronitrile and other azo-based or diazo-based polymerization initiators; etc.

[0108] (Filtration step, washing step, drying step, classification step, external addition step) Thereafter, a filtration step for filtering the solid content of the toner particles, a washing step if necessary, a drying step, and a classification step for adjusting the particle size are performed to obtain toner particles. The toner particles may be used as the toner as they are. If necessary, the toner particles and an external additive such as inorganic fine powder are mixed and adhered using a mixer to obtain a toner.

[0109] 〔Method for Measuring Physical Properties〕 The measurement methods for various physical properties will be described below.

[0110] <Method for Measuring Weight-Average Particle Size (D4) and Number-Average Particle Size (D1)> The weight-average particle size (D4) and number-average particle size (D1) of the toner are calculated as follows. As the measuring device, a precision particle size distribution measuring device "Coulter Counter Multisizer 3" (registered trademark, manufactured by Beckman Coulter, Inc.) using a pore electrical resistance method equipped with a 100 μm aperture tube is used. For the setting of the measurement conditions and the analysis of the measurement data, the attached dedicated software "Beckman Coulter Multisizer 3 Version 3.51" (manufactured by Beckman Coulter, Inc.) is used. Incidentally, the measurement is performed with an effective number of measurement channels of 25,000 channels.

[0111] The electrolytic aqueous solution used for the measurement is a solution obtained by dissolving special grade sodium chloride in ion-exchanged water so that the concentration becomes about 1% by mass. For example, "ISOTON II" (manufactured by Beckman Coulter, Inc.) can be used.

[0112] Incidentally, before performing the measurement and analysis, the settings of the dedicated software were made as follows.

[0113] On the "Change Standard Measurement Method (SOMME)" screen of the dedicated software, set the total count number in the control mode to 50,000 particles, the number of measurements to 1 time, and the Kd value to the value obtained using "Standard Particle 10.0 μm" (manufactured by Beckman Coulter, Inc.). By pressing the "Measurement Button for Threshold / Noise Level", the threshold and noise level are automatically set. Also, set the current to 1600 μA, the gain to 2, the electrolyte to ISOTON II, and check "Flash of Aperture Tube after Measurement".

[0114] On the "Conversion Setting from Pulse to Particle Size" screen of the dedicated software, set the bin interval to logarithmic particle size, the particle size bin to 256 particle size bins, and the particle size range to 2 μm to 60 μm.

[0115] The specific measurement method is as follows. (1) Put about 200 ml of the electrolytic aqueous solution into a 250-ml round-bottom glass beaker dedicated to Multisizer 3, set it on the sample stand, and stir with a stirrer rod counterclockwise at 24 revolutions per second. Then, use the "aperture flash" function of the dedicated software to remove dirt and bubbles in the aperture tube. (2) Put about 30 ml of the electrolytic aqueous solution into a 100-ml flat-bottom glass beaker. Add about 0.3 ml of a dilution obtained by diluting "Contaminon N" (a 10% by mass aqueous solution of a neutral detergent for precision measuring instrument cleaning with a pH of 7 composed of a nonionic surfactant, an anionic surfactant, and an organic builder, manufactured by Wako Pure Chemical Industries, Ltd.) about 3 times by mass with ion-exchanged water as a dispersant. (3) Prepare an ultrasonic disperser "Ultrasonic Dispersion System Tetra150" (manufactured by Nikkaki Bios Co., Ltd.) with two oscillators having an oscillation frequency of 50 kHz and a phase shift of 180 degrees and an electrical output of 120 W. Put about 3.3 l of ion-exchanged water into the water tank of the ultrasonic disperser, and add about 2 ml of Contaminon N to this water tank. (4) Set the beaker in (2) in the beaker fixing hole of the ultrasonic disperser and operate the ultrasonic disperser. Then, adjust the height position of the beaker so that the resonance state of the liquid level of the electrolytic aqueous solution in the beaker is maximized. (5) While irradiating the electrolytic aqueous solution in the beaker in (4) with ultrasonic waves, add about 10 mg of toner little by little to the electrolytic aqueous solution and disperse it. Then, continue the ultrasonic dispersion treatment for another 60 seconds. In ultrasonic dispersion, adjust appropriately so that the water temperature in the water tank is 10°C or higher and 40°C or lower. (6) Drop the electrolytic aqueous solution in (5) in which the toner is dispersed into the round-bottom beaker in (1) installed in the sample stand using a pipette, and adjust so that the measurement concentration is about 5%. Then, perform the measurement until the number of measured particles reaches 50,000. (7) Analyze the measurement data using the dedicated software attached to the apparatus to calculate the weight average particle diameter (D4) and the number average particle diameter (D1). When set to graph / volume% in the dedicated software, the "average diameter" on the "Analysis / Volume Statistical Value (Arithmetic Mean)" screen is the weight average particle diameter (D4), and when set to graph / number% in the dedicated software, the "average diameter" on the "Analysis / Number Statistical Value (Arithmetic Mean)" screen is the number average particle diameter (D1).

[0116] <Method for Obtaining Reflection Electron Image of Toner Surface> The matrix exposure rate of the toner is calculated using the reflection electron image of the toner particle surface.

[0117] The reflection electron image of the toner surface was obtained by a scanning electron microscope (SEM).

[0118] The reflection electron image obtained from the SEM is also called a "composite image", and substances with a smaller atomic number are detected darker, while those with a larger atomic number are detected brighter.

[0119] Toner particles are generally resin particles mainly containing a composition mainly composed of carbon such as a resin component and a release agent. When silica fine particles or metal oxides are present on the toner particle surface, in the reflection electron image obtained from the SEM, the silica fine particles or metal oxides are observed as bright parts, and the resin part mainly composed of carbon is observed as a dark part.

[0120] The SEM apparatus and observation conditions are as follows. Apparatus used: ULTRA PLUS manufactured by Carl Zeiss Microscopy GmbH Acceleration voltage: 1.0 kV WD: 2.0 mm Aperture Size: 30.0 μm Detection signal: EsB (energy-selective backscattered electron) EsB Grid: 800 V Observation magnification: 50,000 times Contrast: 63.0 ± 5.0% (reference value) Brightness: 38.0 ± 5.0% (reference value) Resolution: 1024×768 Pretreatment: Sprinkle toner particles on carbon tape (no vapor deposition)

[0121] The contrast and brightness should be appropriately set according to the status of the equipment in use. Also, the acceleration voltage and EsB Grid should be set to achieve items such as obtaining the structural information of the outermost surface of toner particles, preventing charge-up of the non-vapor-deposited sample, and selectively detecting high-energy reflected electrons. The observation field of view should be selected near the vertex where the curvature of the toner particles is the smallest.

[0122] <Method for confirming that the dark part in the reflected electron image is derived from carbon atoms> To confirm that the dark part in the observed reflected electron image is derived from resin, it is confirmed by overlaying the elemental mapping image obtained by energy-dispersive X-ray analysis (EDS) that can be obtained with a scanning electron microscope (SEM) and the said reflected electron image.

[0123] The equipment and observation conditions of SEM / EDS are as follows. Equipment used (SEM): ULTRA PLUS manufactured by Carl Zeiss Microscopy GmbH Equipment used (EDS): NORANSystem 7, Ultra Dry EDS Detecter manufactured by Thermo Fisher Scientific Inc. Acceleration voltage: 5.0 kV WD: 7.0 mm Aperture Size: 30.0 μm Detection signal: SE2 (secondary electron) Observation magnification: 50,000 times Mode: Spectral Imaging Pretreatment: Sprinkle toner particles on carbon tape and platinum sputtering

[0124] Overlay the elemental mapping image obtained by this method and the said reflected electron image, and confirm that the carbon atom part of the mapping image coincides with the dark part of the reflected electron image.

[0125] <Method for Confirming Dispersion State of Binder Component Contained in Agglomerate> The dispersion state of the binder component contained in the agglomerate is calculated using the backscattered electron image of the agglomerate on the toner surface. The backscattered electron image of the agglomerate on the toner surface is obtained in the same manner as the method for obtaining the backscattered electron image of the toner surface.

[0126] For the obtained backscattered electron image, the dispersion state of the resin particles contained in the agglomerate is calculated using the image processing software ImageJ (developed by Wayne Rashand). The procedure is shown below.

[0127] First, convert the backscattered electron image to be analyzed to 8-bit from the Type in the Image menu. Next, set the median diameter to 2.0 pixels from the Filters in the Process menu to reduce image noise. Estimate the center of the image excluding the observation condition display section shown at the bottom of the backscattered electron image, and select a range of 1.5 μm square from the center of the backscattered electron image using the rectangle tool in the toolbar.

[0128] Next, select Threshold from Adjust in the Image menu. In the manual operation, select all the pixels corresponding to the luminance B1 and click Apply to obtain a binary image. By this operation, the pixels corresponding to A1 are displayed in black (pixel group A1), and the pixels corresponding to A2 are displayed in white (pixel group A2). Again, estimate the center of the image excluding the observation condition display section shown at the bottom of the backscattered electron image, and select a range of 1.5 μm square from the center of the backscattered electron image using the rectangle tool in the toolbar.

[0129] Next, select the scale bar in the observation condition display section at the bottom of the backscattered electron image using the straight line tool in the toolbar. When Set Scale in the Analyze menu is selected in this state, a new window opens, and the pixel distance of the selected straight line is input in the Distance in Pixels column. Enter the value of the scale bar (e.g., 100) in the Known Distance column of the window, enter the unit of the scale bar (e.g., nm) in the Unit of Mesurement column, and click OK to complete the scale setting.

[0130] Subsequently, select Set Mesurements in the Analyze menu and check Area and Feret’s diameter. Select Analyze Particles in the Analyze menu, check Display Result and click OK to perform domain analysis.

[0131] Subsequently, perform an Erode process for 10 pixels on the obtained analysis image using ImageJ, and then perform a Dilate process for 10 pixels using ImageJ. Note that the Erode process and the Dilate process are performed from the Binary item in the Process menu. Figure 2 illustrates an image obtained by performing the above processes.

[0132] For the analysis image obtained after the above process, using the straight line tool (Straight Line) in the toolbar, with the midpoint of the analysis image as the reference point, draw a total of 18 straight lines at 10° intervals from one end to the other end of the image so that they pass through the reference point. Figure 3 illustrates the image with the line segments drawn.

[0133] Subsequently, measure the length L of the line segment where the bright part is continuous on the straight line, count the number of straight lines having a line segment with the length L of 100 nm or more, and check whether the number of straight lines in the agglomerate is 12 or more.

[0134] <Method for checking the ratio of toner particles having an agglomerate with 12 or more straight lines> For 30 toner particles having agglomerates contained in the toner to be evaluated, perform the above procedure on the agglomerates, count the number of toner particles having an agglomerate with 12 or more straight lines, and calculate the ratio A of the toner particles containing an agglomerate with 12 or more straight lines from the following formula. A = (the number of toner particles containing agglomerates where the number of the straight lines is 12 or more) / 30

[0135] <Method for confirming the area ratio of the binder component contained in the agglomerate> The area ratio of the binder component is calculated based on the domain D1 of the binder component and the domain D2 that is not the binder component using the backscattered electron image of the agglomerate on the toner surface. The backscattered electron image of the agglomerate on the toner surface is obtained in the same manner as the method for obtaining the backscattered electron image of the toner surface.

[0136] The analysis of domains D1 and D2 is performed using the image processing software ImageJ (developed by Wayne Rasband) on the outermost surface backscattered electron image of the toner particles obtained by the above method. The procedure is shown below.

[0137] First, convert the backscattered electron image to be analyzed to 8-bit from the Type in the Image menu. Next, set the Median diameter to 2.0 pixels from the Filters in the Process menu to reduce image noise. Estimate the center of the image excluding the observation condition display part displayed at the bottom of the backscattered electron image, and select a range of 1.5 μm square from the center of the backscattered electron image using the rectangle tool in the toolbar.

[0138] Next, select only the part where the carbon atom part of the mapping image coincides with the dark part of the backscattered electron image using the Freehand selections function in the Image menu, and fill it all in black. Also, fill in all the parts other than the part where the carbon atom part of the mapping image coincides with the dark part of the backscattered electron image in white. Next, select Threshold from Adjust. In manual operation, select 128, which is the middle tone between black and white in an 8-bit image, as the threshold value, and click Apply to obtain a binary image.

[0139] By this operation, the pixels corresponding to domain D1 (binder component) are displayed in black (pixel group A1), and the pixels corresponding to domain D2 (other than the binder component) are displayed in white (pixel group A2).

[0140] Again, estimate the image center excluding the observation condition display section shown at the bottom of the secondary electron image, and select a range of 1.5 μm square from the image center of the secondary electron image using the Rectangle Tool in the toolbar.

[0141] Next, select the scale bar in the observation condition display section shown at the bottom of the secondary electron image using the Straight Line tool in the toolbar. When Set Scale in the Analyze menu is selected in this state, a new window opens and the pixel distance of the selected straight line is input in the Distance in Pixels column.

[0142] Input the value of the scale bar (e.g., 100) in the Known Distance column of the window, input the unit of the scale bar (e.g., nm) in the Unit of Measurement column, and click OK to complete the scale setting.

[0143] Subsequently, select Set Measurements in the Analyze menu and check Area and Feret’s diameter. When Analyze Particles in the Analyze menu is selected, check Display Result and click OK to perform domain analysis.

[0144] From the newly opened Results window, obtain the area of each domain corresponding to domain D1 formed by pixel group A1 and domain D2 formed by pixel group A2.

[0145] Let the sum of the areas of the binder component domains D1 be S1 (μm 2 ), and let the sum of the areas of the domains D2 other than the binder component be S2 (μm 2 ). Calculate the binder component area ratio S from the obtained S1 and S2 using the following formula. S (area %) = {S1 / (S1 + S2)} × 100

[0146] Perform the above procedure for 10 fields of view for the toner particles to be evaluated, and use the arithmetic mean value as the binder component area ratio.

[0147] <Method for Confirming Area Ratio of Fatty Acid Metal Salt Contained in Agglomerate> Basically, the area ratio of the fatty acid metal salt is confirmed in the same way as the area ratio of the binder component. That is, it is calculated based on domain D3 of the fatty acid metal salt component and domain D4 that is not the fatty acid metal salt component, using the backscattered electron image of the agglomerate on the toner surface. The backscattered electron image of the agglomerate on the toner surface is obtained in the same manner as the method for obtaining the backscattered electron image of the toner surface.

[0148] The analysis of domains D3 and D4 is performed using the image processing software ImageJ (developed by Wayne Rashand) on the outermost surface backscattered electron image of the toner particles obtained by the above method.

[0149] The analysis is the same as in the case of the binder resin area ratio, but the method for selecting D3 is carried out as follows. Using the Freehand selections function in the Image menu, select only the part where the part with the presence of zinc or calcium, magnesium, aluminum in the elemental mapping image matches the part with the contrast between the bright part of silica and the dark part of the binder resin in the backscattered electron image, and fill it all in black. Also, fill in white all parts other than the part where the part with the presence of zinc or calcium, magnesium, aluminum in the elemental mapping image matches the part with the contrast between the bright part of silica and the dark part of the binder resin in the backscattered electron image. Next, select Threshold from Adjust. In manual operation, select 128, which is the middle tone between black and white in an 8-bit image, as the threshold value, and click Apply to obtain a binary image.

[0150] By this operation, the pixels corresponding to domain D3 (fatty acid metal salt component) are displayed in black (pixel group A3), and the pixels corresponding to domain D4 (other than fatty acid metal salt) are displayed in white (pixel group A4).

[0151] Again, estimate the image center excluding the observation condition display part shown at the bottom of the secondary electron image, and select a range of 1.5 μm square from the image center of the secondary electron image using the Rectangle Tool in the toolbar.

[0152] Next, using the Straight Line in the toolbar, select the scale bar in the observation condition display part shown at the bottom of the secondary electron image. When Set Scale in the Analyze menu is selected in this state, a new window opens and the pixel distance of the selected straight line is input in the Distance in Pixels column.

[0153] Input the value of the scale bar (for example, 100) in the Known Distance column of the window, input the unit of the scale bar (for example, nm) in the Unit of Measurement column, and click OK to complete the scale setting.

[0154] Subsequently, select Set Measurements in the Analyze menu, and check Area and Feret’s diameter. When Analyze Particles in the Analyze menu is selected, check Display Result and click OK to perform domain analysis.

[0155] From the newly opened Results window, obtain the area of each domain corresponding to the domain D3 formed by the pixel group A3 and the domain D4 formed by the pixel group A4.

[0156] Let the sum of the areas of the fatty acid metal salt component domains D3 be S3 (μm 2 ), and let the sum of the areas of the domains D4 other than the fatty acid metal salt component be S4 (μm 2 ). Calculate the fatty acid metal salt component area ratio S from the obtained S3 and S4 using the following formula. S (area %) = {S3 / (S3 + S4)} × 100

[0157] The above procedure is performed for 10 fields of view for the toner particles to be evaluated, and the additive average value is used as the fatty acid metal salt area ratio.

[0158] <Method for observing toner and method for calculating number of toner particles> The toner is observed using a scanning electron microscope (SEM).

[0159] The SEM apparatus and observation conditions are as follows. Apparatus used: ULTRA PLUS manufactured by Carl Zeiss Microscopy Co., Ltd. Acceleration voltage: 1.0 kV WD: 2.0 mm Aperture Size: 30.0 μm Detection signal: SE2 (secondary electron) Observation magnification: 2,000 times Contrast: 45.0 ± 5.0% (reference value) Brightness: 38.0 ± 5.0% (reference value) Resolution: 1024 × 768 Pretreatment: Sprinkle toner particles on carbon tape (no vapor deposition)

[0160] The contrast and brightness are appropriately set according to the state of the apparatus used. Also, the acceleration voltage is set so as to achieve items such as acquisition of the outermost surface structure information of the toner particles and prevention of charge-up of the non-vapor-deposited sample.

[0161] The number of observation fields of view is observed until the number of fields of view reaches the number of toner particles whose entire particles are within the observation field of view in the obtained secondary electron image, and when the number is defined as Tall (pieces) and Tall is 300 pieces or more.

[0162] <Method for calculating number CI of toner particles containing agglomerates> In all of the secondary electron images of the number of visual fields obtained from the above observations, count the number of toner particles containing agglomerates among the toner particles whose entire particles are within the observation visual field, and denote it as Tagg (pieces). For the toner containing agglomerates, count the number of toner particles as shown in Fig. 1.

[0163] From the obtained Tall (pieces) and Tagg (pieces), calculate CI (number %) according to the following formula. CI (number %) = Tagg / Tall × 100

[0164] <Method for Measuring Agglomerate Size and Method for Counting Toner Having Agglomerates> In the above-described scanning electron microscope observation, photograph and save the entire toner at an appropriate magnification (5k - 10k). The image resolution shall be 1024 × 768 pixels.

[0165] From the obtained SEM images, select the portions determined to be agglomerates on the image using the image analysis software Image J (developed by Wayne Rasband). The size of the agglomerate is defined by the maximum Feret diameter of this selected area. The calculation procedure is shown below. a) Set the scale in [Analyze] - [Set Scale]. i) Check [Analyze] - [Set Measurements] - [Feret’s diameter]. iii) Select [Freehand Selections] and manually select the agglomerates on the image. iv) Select [Analyze] - [Measure] to obtain the maximum Feret diameter (Feret) of the selected portion. v) If there are multiple agglomerates on the image, repeat steps iii) and iv). vi) Perform the same analysis for the remaining 9 images of the toner having agglomerates with a maximum Feret diameter of 500 nm or more and 8000 nm or less. vii) Take the maximum value of Feret (Feret diameter) of the obtained analysis results as the maximum Feret diameter.

[0166] Agglomerates are those with a maximum Feret diameter of 500 nm or more and 8000 nm or less.

[0167] Optionally observe the toner with a scanning electron microscope, and let Ag be the arithmetic mean value of the maximum Feret diameters of a total of 100 agglomerates.

[0168] Also, among the arbitrarily observed toner particles, let CI be the percentage of the number of toner particles having agglomerates.

[0169] <Evaluation method for the presence of silica fine particles and binder components in agglomerates> Regarding the confirmation of the presence of silica fine particles and binder components in agglomerates, it is carried out using STEM-EDX and a scanning electron microscope.

[0170] First, for the toner having agglomerates, evaluate the cross-sectional structure and composition of the agglomerates using STEM-EDX.

[0171] Using an osmium plasma coater (Filgen, OPC80T), apply an Os film (5 nm) and a naphthalene film (20 nm) to the toner as a protective film, embed it with a photocurable resin D800 (JEOL), and then use an ultrasonic ultramicrotome (Leica, UC7) to produce a cross-section of the toner particle with a film thickness of 100 nm at a cutting speed of 1 mm / s. At this time, it is advisable to process a plurality of toners together to obtain 300 to 500 cross-sections of toners. A schematic diagram of the cross-section of the toner having agglomerates is shown in Figure 4.

[0172] Perform STEM-EDX observation on the obtained cross-section using the STEM function of TEM-EDX (TEM: JEOL, JEM2800 (200 keV), EDX detector: JEOL, dry SD 100GV, EDX system: Thermo Fisher, NORAN SYSTEM7). The probe size of STEM is 1.0 nm, the observation magnification is 50 to 300k, the image size of EDX is 256×256 pixels, and it is acquired by adjusting the storage rate to 10000 cps and integrating 50 frames. The observation location is set so that the field of view includes the agglomerates present in the outer peripheral part of the toner particle.

[0173] The presence of particles mainly composed of silica and a binding component in the agglomerates can be determined by confirming that a portion where a large amount of silicon and oxygen is observed and a portion where a large amount of elements derived from the binding component are observed exist separately at the same location. When a resin is used as the binding component, a large amount of carbon is observed.

[0174] Next, for the toner having agglomerates, observation of a backscattered electron image is performed using a scanning electron microscope. The image capturing conditions are as follows.

[0175] (1) Sample preparation Stick carbon tape on the sample stage (aluminum sample stage 12.5 mm φ × 6 mm t), and place the toner on it. Further, blow air to remove excess sample from the sample stage. Set the sample stage in the sample holder and set it in a scanning electron microscope (UltraPlus manufactured by Zeiss).

[0176] (2) Electron microscope observation condition setting Confirmation of the presence of agglomerates containing silica fine particles and a binding component is performed using the image obtained by observation of the backscattered electron image of Ultra Plus. Since the image contrast changes according to the elemental composition in the backscattered electron image, the presence of silica and the binding component in the agglomerates can be determined. The acceleration voltage is 0.7 kV, the ECB Grid is 500 V, and the WD is 3.0 mm.

[0177] (3) Focus adjustment Set the observation magnification to 30,000 (30k) times and adjust Alignment and Stigma. Next, align the field of view with a region having a form that seems to be an agglomerate at an appropriate observation magnification. From the obtained backscattered electron image, it can be determined that it is the same as the agglomerate for which compositional observation was performed by STEM-EDX, having two types of contrasts, one corresponding to silica and the other corresponding to the binding component.

[0178] <Method for calculating the percentage ratios Ca and Cb of the number of toner particles having agglomerates when ultrasonic treatment is performed> Put about 10 ml of ion-exchanged water from which impurities and the like have been removed in advance into a glass container.

[0179] Add about 0.5 ml of a dilution obtained by diluting "Contaminon N" (a 10% by mass aqueous solution of a neutral detergent for precision measuring instrument cleaning with a pH of 7, composed of a nonionic surfactant, an anionic surfactant, and an organic builder, manufactured by Wako Pure Chemical Industries, Ltd.) about 3 times by mass with ion-exchanged water as a dispersant. Further, add about 0.02 g of the measurement sample, and while stirring, perform the following dispersion treatment using an ultrasonic disperser to obtain a dispersion for measurement. At this time, appropriately cool so that the temperature of the dispersion becomes 10°C or higher and 40°C or lower. As the ultrasonic disperser, use an ultrasonic homogenizer with an oscillation frequency of 30 kHz ("VP-050" (manufactured by TAITEC)), insert the vibrating part 1.0 cm into the dispersion, and vibrate it under the following ultrasonic condition A or ultrasonic condition B. · Ultrasonic condition A: Output frequency 30 kHz, output capacity 0.75 W, irradiation time 300 s · Ultrasonic condition B: Output frequency 30 kHz, output capacity 25 W, irradiation time 300 s Filter the dispersion obtained by the above procedure using a Kiriyama filter paper (No. 5C: pore diameter 1 μm) to separate the particles and the filtrate. Wash the obtained particles with 100 parts by mass of ion-exchanged water, and perform vacuum drying at 25°C for 24 hours to obtain a powder for measuring the number Ca and Cb of toner particles containing agglomerates.

[0180] For the obtained powder, calculate Ca and Cb by the same procedure as the "method for calculating the number CI of toner particles having agglomerates", and confirm whether the relationships of the following formulas (1) and (2) are satisfied. 0.90 ≦ Ca / CI ≦ 1.00 Formula (1) 0.10 ≦ Cb / CI ≦ 0.40 Formula (2)

[0181] <Method for Identifying Fatty Acid Metal Salt> (1) Method for Isolating Fatty Acid Metal Salt Particles from Toner If necessary, the fatty acid metal salt can be isolated from the toner by the following method.

[0182] Add 160 g of sucrose (manufactured by Kinoshita Chemical Co., Ltd.) to 100 mL of ion-exchanged water, and dissolve it while stirring with hot water to prepare a thick sucrose solution. Place 6 mL of Contaminon N (a 10% by mass aqueous solution of a neutral detergent for precision measuring instruments with a pH of 7, composed of a nonionic surfactant, an anionic surfactant, and an organic builder, manufactured by Wako Pure Chemical Industries, Ltd.) in a centrifuge tube (capacity 50 ml). Add 1.0 g of toner to this, and loosen the toner clumps with a spatula or the like.

[0183] Using an ultrasonic homogenizer with an oscillation frequency of 30 kHz (「VP-050」(manufactured by TAITEC Corporation)), insert the vibrating part 1.0 cm into the toner dispersion liquid, and vibrate it under the following ultrasonic condition B. Ultrasonic condition B: Output frequency 30 kHz, output power 25 W, irradiation time 300 s Add 31 g of the thick sucrose solution to the above centrifuge tube, and shake it at 300 spm (strokes per min) for 20 minutes using a shaker (sold by AS ONE Corporation). After shaking, transfer the solution to a glass tube (50 mL) for a swinging rotor, and separate it in a centrifuge (manufactured by Kokusan Co., Ltd., model H-9R) under the conditions of 3500 rpm for 30 minutes.

[0184] By this operation, visually confirm that the toner particles and the aqueous solution are sufficiently separated, and collect the separated toner particles in the uppermost layer with a spatula or the like to separate the toner particles from the dispersion liquid.

[0185] After that, centrifuge the dispersion liquid after collecting the toner particles again, and collect the dispersion liquid containing the fatty acid metal salt separated in the upper layer again.

[0186] Then repeat the above operation. After collecting the dispersion liquid containing the fatty acid metal salt, centrifuge it again to obtain a concentrated solution with an increased concentration of the fatty acid metal salt.

[0187] After allowing the concentrated solution to air-dry for one day, dry it in a dryer at 40 °C for 8 hours or more to obtain a sample for measurement. Repeat this operation multiple times to secure the required amount of isolated fatty acid metal salt particles.

[0188] (2) Identification of the central metal by X-ray fluorescence Using the isolated fatty acid metal salt particles, X-ray fluorescence measurement was performed and composition analysis was carried out to identify the metal elements of the fatty acid metal salt particles.

[0189] (3) Identification of the fatty acid of the fatty acid metal salt by pyrolysis GC-MS The specific conditions for identifying the fatty acid by pyrolysis GC-MS are shown below. Mass spectrometer: ISQ from Thermo Fisher Scientific GC device: Focus GC from Thermo Fisher Scinetific Ion source temperature: 250 °C Ionization method: EI Mass range: 50 - 1000 m / z Column: HP-5MS [30 m] Pyrolysis device: JPS-700 manufactured by Nippon Analytical Industry Co., Ltd.

[0190] Add 1 μL of the fatty acid metal salt separated by the isolation operation and tetramethylammonium hydroxide (TMAH) to the pyrolysis foil at 590 °C. The prepared sample was subjected to pyrolysis GC-MS measurement under the above conditions to obtain a peak derived from the fatty acid metal salt. Due to the action of TMAH, which is a methylating agent, the fatty acid component is detected as a methylated product. The obtained peak was analyzed to identify the fatty acid structure of the fatty acid metal salt.

[0191] [Constitutions included in the embodiments of the present invention] The disclosure of this embodiment includes the following constitutions. (Constitution 1) A toner having toner particles, On the surface of the toner particles, there are agglomerates containing silica fine particles and a binder component. Further, the toner has fatty acid metal salt particles, The arithmetic mean value Ag of the Feret diameter of the agglomerates is 1000 nm or more and 8000 nm or less. When the number ratio of the toner particles having the agglomerates is CI (number %), the CI is 1 number % or more and 15 number % or less, When the percentage of toner particles having the agglomerates in the toner after being treated under the following ultrasonic condition A is defined as Ca (number %), and the percentage of toner particles having the agglomerates in the toner after being treated under the following ultrasonic condition B is defined as Cb (number %), A toner characterized in that the CI, the Ca, and the Cb satisfy the formulas (1) and (2). · Ultrasonic condition A: Output frequency 30 kHz, output power 0.75 W, irradiation time 300 s · Ultrasonic condition B: Output frequency 30 kHz, output power 25 W, irradiation time 300 s 0.90 ≦ Ca / CI ≦ 1.00 Formula (1) 0.10 ≦ Cb / CI ≦ 0.40 Formula (2) (Configuration 2) The toner according to Configuration 1, wherein the fatty acid metal salt particles are contained inside the agglomerates or present on the surface of the toner particles. (Configuration 3) The toner according to Configuration 1 or 2, wherein the area ratio of the binding component of the agglomerates is 5% or more and 50% or less with respect to the entire agglomerates on the surface observed by a scanning electron microscope of the toner particles having the agglomerates. (Configuration 4) The toner according to any one of Configurations 1 to 3, wherein the toner contains 0.1 mass % or more and 3.0 mass % or less of the fatty acid metal salt particles. (Configuration 5) The toner according to any one of Configurations 1 to 4, wherein the abundance ratio YA (number %) of particles having a size of less than 4 μm when the dispersion obtained by treating the toner under the ultrasonic condition A is measured by a flow type particle image measuring device is 20 number % or more and 50 number % or less. (Configuration 6) The toner according to any one of Configurations 1 to 5, wherein the area ratio of the fatty acid metal salt of the agglomerates is 2% or more and 30% or less with respect to the entire agglomerates on the surface observed by a scanning electron microscope of the toner particles having the agglomerates. (Configuration 7) The toner according to any one of Configurations 1 to 6, wherein the toner has silicone resin fine particles as an external additive on the surface of the toner particles.

Examples

[0192] The present invention will be specifically described by the following production examples and examples. However, these do not limit the present invention in any way. In the production examples and examples, "parts" are all based on mass unless otherwise specified.

[0193] A production example of toner particles will be described.

[0194] <Preparation of Resin Particle Dispersion Liquid 1> 78.0 parts of styrene, 20.7 parts of butyl acrylate, 1.3 parts of acrylic acid as a monomer for imparting a carboxyl group, and 3.2 parts of n-lauryl mercaptan were mixed and dissolved. To this solution, an aqueous solution prepared by dissolving 2.0 parts of sodium linear alkylbenzene sulfonate (product name: Neogen RK (manufactured by Daiichi Kogyo Seiyaku Co., Ltd.)) in 150 parts of ion-exchanged water was added in its entirety and dispersed.

[0195] While stirring slowly for another 10 minutes, an aqueous solution of 0.3 part of potassium persulfate and 10 parts of ion-exchanged water was added. After nitrogen substitution, emulsion polymerization was carried out at 70°C for 6 hours. After the polymerization was completed, the reaction solution was cooled to room temperature, and ion-exchanged water was added to obtain Resin Particle Dispersion Liquid 1 with a solid content concentration of 12.5% by mass and a median diameter of 0.2 μm based on volume.

[0196] <Preparation of Release Agent Dispersion Liquid 1> 100 parts of a release agent (behenyl behenate, melting point: 72.1°C) and 15 parts of an aliphatic alcohol alkylene oxide adduct were mixed with 385 parts of ion-exchanged water, and dispersed using a wet jet mill JN100 (manufactured by Tokko Co., Ltd.) for about 1 hour to obtain Release Agent Dispersion Liquid 1. The concentration of the release agent dispersion liquid was 20% by mass.

[0197] <Preparation of Colorant Dispersion Liquid 1> 100 parts of carbon black "Nipex35 (manufactured by Orion Engineered Carbons S.A.)" as a colorant and 15 parts of an aliphatic alcohol alkylene oxide adduct were mixed with 885 parts of ion-exchanged water, and dispersed using a wet jet mill JN100 for about 1 hour to obtain Colorant Dispersion Liquid 1.

[0198] <Production Example of Toner Core Particle Dispersion Liquid 1> (Dispersion Step) 265 parts of Resin Particle Dispersion Liquid 1, 10 parts of Release Agent Dispersion Liquid 1, 10 parts of Colorant Dispersion Liquid 1, 2.9 parts of aliphatic alcohol alkylene oxide adduct, and 0.6 part of sodium linear alkylbenzene sulfonate (Neogen RK) were dispersed using a homogenizer (Ultra Turrax T50 manufactured by IKA). While stirring, the temperature inside the container was adjusted to 30°C, and an aqueous solution of 1 mol / L sodium hydroxide was added to adjust the pH to 8.0.

[0199] (Aggregation Step) As a flocculant, an aqueous solution prepared by dissolving 0.08 part of aluminum chloride in 10 parts of ion-exchanged water was added over 10 minutes with stirring at 30°C. After leaving it standing for 3 minutes, the temperature was raised, and the temperature was raised to 50°C to form associated particles. In that state, the particle size of the associated particles was measured using a "Coulter Counter Multisizer 3" (registered trademark, manufactured by Beckman Coulter). When the weight average particle size reached 7.0 μm, 0.9 part of sodium chloride and 5.0 parts of aliphatic alcohol were added to stop particle growth.

[0200] An aqueous solution of 1 mol / L sodium hydroxide was added to adjust the pH to 9.0, and then the temperature was raised to 95°C to spheroidize the aggregated particles. When the average circularity reached 0.980, the temperature was lowered, and it was cooled to room temperature to obtain Toner Core Particle Dispersion Liquid 1.

[0201] <Production Example of Monomer Dispersion Liquid 1 Containing Silica Fine Particles, Binder Component, and Fatty Acid Metal Salt Particles> 100 parts of styrene, 20 parts of methacryloxypropyltrimethoxysilane, 70 parts of colloidal silica, and 30 parts of zinc stearate were dispersed using a homogenizer (Ultra Turrax T50 manufactured by IKA), the temperature inside the container was adjusted to 25°C, and it was stirred for 1 hour to obtain Monomer Dispersion Liquid 1 containing silica fine particles, a binder component, and fatty acid metal salt particles.

[0202] <Production Examples of Monomer Dispersion Liquids 2 to 15 Containing Silica Fine Particles, Binder Component, and Fatty Acid Metal Salt Particles> In the preparation of the monomer dispersion liquid 1, monomer dispersion liquids 2 to 15 were obtained in the same manner except that the number of parts and the types of materials were changed as described in Table 1.

[0203] <Production Example of Silicone Resin Fine Particles> 360.0 parts of water was placed in a reaction vessel equipped with a thermometer and a stirrer, and 15.0 parts of hydrochloric acid with a concentration of 5.0 mass% was added to form a uniform solution. While stirring this at a temperature of 25°C, 136.0 parts of methyltrimethoxysilane was added, and after stirring for 5 hours, it was filtered to obtain a transparent reaction solution containing a silanol compound or its partial condensate.

[0204] 440.0 parts of water was placed in a reaction vessel equipped with a thermometer, a stirrer, and a dropping device, and 17.0 parts of aqueous ammonia with a concentration of 10.0 mass% was added to form a uniform solution. While stirring this at a temperature of 35°C, 100 parts of the reaction solution obtained in the above step was added dropwise over 0.5 hours, and after stirring for 6 hours, a suspension was obtained. The obtained suspension was centrifuged to precipitate and extract the fine particles, and then dried in a dryer at a temperature of 200°C for 24 hours to obtain silicone resin fine particles.

[0205] For the obtained silicone resin fine particles, the number average particle diameter of the primary particles was 100 nm as determined by a transmission scanning electron microscope.

[0206]

Table 1

[0207] <Production Example of Toner 1> To 100 parts of the toner core particle dispersion liquid 1, 2.75 parts of the monomer dispersion liquid 1 obtained by the above method and 0.005 part of potassium persulfate were added, the temperature inside the container was adjusted to 90°C, and it was stirred for 2 hours using a full zone stirring blade to obtain the toner particle dispersion liquid 1.

[0208] Hydrochloric acid was added to the obtained toner particle dispersion 1 and adjusted to a pH of 1.5 or less, and then left to stir for 1 hour. After that, solid-liquid separation was performed using a pressure filter to obtain a toner cake. This was reslurried with ion-exchanged water to form a dispersion again, and then solid-liquid separation was performed using the aforementioned filter. Reslurrying and solid-liquid separation were repeated until the electrical conductivity of the filtrate became 5.0 μS / cm or less. Finally, solid-liquid separation was performed to obtain a toner cake. The obtained toner cake was dried and further classified using a classifier to obtain toner particles 1. The weight average particle diameter of the toner particles 1 was 6.9 μm.

[0209] 0.4 part of silicone resin fine particles was added to 100 parts of toner particles 1 and put into an FM mixer (FM10C type manufactured by Nippon Coke Industry Co., Ltd.) with water at 7°C flowing through the jacket. After the water temperature in the jacket was stabilized at 7°C ± 1°C, mixing was performed at a peripheral speed of the rotating blades of 38 m / sec for 5 minutes to obtain a toner mixture 1. At this time, the water flow rate in the jacket was appropriately adjusted so that the temperature inside the tank of the FM mixer did not exceed 25°C. The obtained toner mixture 1 was sieved with a mesh having an opening of 75 μm to obtain toner 1. The physical properties of the obtained toner 1 are shown in Table 3-1 and Table 3-2.

[0210] <Production Examples of Toner 2 to 6, 8 to 23, 25> In the production example of toner 1, toner 2 to 6, 8 to 23, and 25 were obtained in the same manner except that the number of parts, the type of material, and the production conditions were changed as described in Table 2. The physical properties of the obtained toner 2 to 6, 8 to 23, and 25 are shown in Table 3-1 and Table 3-2.

[0211] <Production Example of Toner 7> 0.6 part of the monomer dispersion 2 obtained by the above method and 0.001 part of potassium persulfate were added to 100 parts of the toner core particle dispersion 1. After adjusting the temperature inside the container to 90°C, dispersion was performed for 10 minutes using a homogenizer (Ultra Turrax T50 manufactured by IKA), and stirring was performed for 2 hours using a full zone stirring blade to obtain a toner particle dispersion 7.

[0212] Hydrochloric acid was added to the obtained toner particle dispersion 7 to adjust the pH to 1.5 or less, and the mixture was stirred and left for 1 hour, followed by solid-liquid separation using a pressure filter to obtain a toner cake. This was reslurried with ion-exchanged water to form a dispersion again, and then solid-liquid separation was performed using the aforementioned filter. Reslurrying and solid-liquid separation were repeated until the electrical conductivity of the filtrate reached 5.0 μS / cm or less, and finally solid-liquid separation was performed to obtain a toner cake. The obtained toner cake was dried and further classified using a classifier to obtain toner particles 7. The weight average particle diameter of the toner particles 7 was 6.9 μm.

[0213] 0.4 part of silicone resin fine particles was added to 100 parts of toner particles 7 and put into an FM mixer (FM10C type manufactured by Nippon Coke & Engineering Co., Ltd.) with water at 7°C flowing through the jacket. After the water temperature in the jacket stabilized at 7°C ± 1°C, mixing was carried out at a peripheral speed of the rotating blades of 38 m / sec for 5 minutes to obtain a toner mixture 7. At this time, the water flow rate in the jacket was appropriately adjusted so that the temperature inside the tank of the FM mixer did not exceed 25°C. The obtained toner mixture 7 was sieved through a mesh with an opening of 75 μm to obtain toner 7. The physical properties of the obtained toner 7 are shown in Table 3-1 and Table 3-2.

[0214] <Production Example of Toner 24> To 100 parts of the toner core particle dispersion 1, 0.6 part of the monomer dispersion 2 obtained by the above method and 0.001 part of potassium persulfate were added. After adjusting the temperature inside the container to 90°C, dispersion was carried out for 30 minutes using a homogenizer (Ultra-Turrax T50 manufactured by IKA), and then stirring was carried out for 2 hours using a full-zone stirring blade to obtain a toner particle dispersion 24.

[0215] Hydrochloric acid was added to the obtained toner particle dispersion 24, adjusted to a pH of 1.5 or less, stirred and allowed to stand for 1 hour, and then solid-liquid separation was performed using a pressure filter to obtain a toner cake. This was reslurried with ion-exchanged water to form a dispersion again, and then solid-liquid separation was performed using the aforementioned filter. Reslurrying and solid-liquid separation were repeated until the electrical conductivity of the filtrate reached 5.0 μS / cm or less, and finally solid-liquid separation was performed to obtain a toner cake. The obtained toner cake was dried and further classified using a classifier to obtain toner particles 24. The weight average particle diameter of the toner particles 24 was 6.9 μm.

[0216] 0.4 part of silicone resin fine particles was added to 100 parts of the toner particles 24 and put into an FM mixer (FM10C type manufactured by Nippon Coke & Engineering Co., Ltd.) with water at 7°C flowing through the jacket. After the water temperature in the jacket stabilized at 7°C ± 1°C, mixing was performed at a peripheral speed of the rotating blades of 38 m / sec for 5 minutes to obtain a toner mixture 24. At this time, the water flow rate in the jacket was appropriately adjusted so that the temperature inside the tank of the FM mixer did not exceed 25°C. The obtained toner mixture 24 was sieved with a mesh having an opening of 75 μm to obtain toner 24. The physical properties of the obtained toner 24 are shown in Table 3-1 and Table 3-2.

[0217]

Table 2

[0218]

Table 3-1

[0219]

Table 3-2

[0220] 〔Example 1〕 Regarding the above-obtained toner 1, the following evaluations were performed.

[0221] The HP Color Laser jet Enterprise M653dn was prepared as an electrophotographic apparatus, and the black cartridge was filled with toner 1. In addition, considering the future higher speed and longer life of the printer, the M653dn was used after modifying the process speed to 400 mm / s. As the evaluation paper, A4 color laser copy paper (manufactured by Canon, 80 g / m 2 ) was used.

[0222] <Evaluation of developing streaks in normal temperature and humidity and high temperature and high humidity environments> The evaluation of developing streaks caused by toner fusion in the developing unit was carried out in a normal temperature and humidity environment (25°C / 50%RH) and a high temperature and high humidity environment (30°C / 80%RH). Assuming a long-term durability test, a horizontal line pattern with a printing rate of 1% was set as 2 sheets / 1 job, and the machine was set to stop once between jobs and then the next job would start. In this mode in each environment, after conducting a printing test of 30,000 sheets in total, a halftone image (H.T. image) was printed, and the number of streaks on the image was measured. Also, to confirm that it was a developing streak, the streaks on the developing roller were also checked to confirm the presence of streaks that matched the image. A: 0 streaks. B: 1 streak. C: 2 - 3 streaks. D: 4 or more streaks.

[0223] <Evaluation of contamination of the charging roller> The evaluation of contamination of the charging roller was carried out in a normal temperature and humidity environment (25°C / 50%RH). Assuming a long-term durability test, a horizontal line pattern with a printing rate of 1% was set as 2 sheets / 1 job, and the machine was set to stop once between jobs and then the next job would start. In this mode, a printing test of 30,000 sheets in total was conducted, and after the test, the surface of the charging roller and the halftone image were visually observed and evaluated based on the following evaluation criteria. A: No defects are observed on either the surface of the charging roller or the image. B: Slight dirt is observed on the surface of the charging roller, but it does not appear on the image. C: Dirt is observed on the surface of the charging roller, and unevenness in image density is also starting to be noticeable. D: It can be confirmed that dirt is observed on the surface of the charging roller, and density unevenness is clearly present in the image.

[0224] 〔Examples 2 to 17, Comparative Examples 1 to 8〕 Evaluation was performed in the same manner as in Example 1, except that the toner filled in the cartridge was changed as shown in Table 4. The evaluation results are shown in Table 4.

[0225]

Table 4

Claims

1. A toner having toner particles, agglomerates containing silica fine particles and a binder component are present on the surface of the toner particles, and the toner further contains fatty acid metal salt particles; The arithmetic mean value Ag of the Feret's diameter of the aggregates is 1000 nm or more and 8000 nm or less, When the number ratio of the toner particles having the agglomerates is defined as CI (number %), the CI is 1 number % or more and 15 number % or less, When the percentage of the number of toner particles having the agglomerates in the toner treated under the ultrasonic condition A is Ca (number %), and the percentage of the number of toner particles having the agglomerates in the toner treated under the ultrasonic condition B is Cb (number %), The toner, wherein the CI, the Ca, and the Cb satisfy the formulas (1) and (2). Ultrasonic condition A: output frequency 30 kHz, output capacity 0.75 W, irradiation time 300 s ・Ultrasonic condition B: output frequency 30kHz, output capacity 25W, irradiation time 300s 0.90≦Ca / CI≦1.00 Formula (1) 0.10≦Cb / CI≦0.40 Formula (2)

2. 2. The toner according to claim 1, wherein the fatty acid metal salt particles are contained inside the agglomerates or are present on the surface of the toner particles.

3. 3. The toner according to claim 1, wherein, when the toner particles having the agglomerates are observed under a scanning electron microscope, the area ratio of the binding component of the agglomerates is 5% or more and 50% or less of the entire agglomerates.

4. 3. The toner according to claim 1, wherein the toner contains the fatty acid metal salt particles in an amount of 0.1% by mass or more and 3.0% by mass or less.

5. 3. The toner according to claim 1, wherein a content YA (number %) of particles smaller than 4 μm when a dispersion liquid obtained by treating the toner under the ultrasonic condition A is measured using a flow type particle image measuring device is 20% by number or more and 50% by number or less.

6. 3. The toner according to claim 1, wherein, when the toner particles having the agglomerates are observed under a scanning electron microscope, the area ratio of the fatty acid metal salt of the agglomerates is 2% or more and 30% or less of the entire agglomerates.

7. 3. The toner according to claim 1, wherein the toner has silicone resin fine particles as an external additive on the surface of the toner particles.

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