Toner external additive, toner and image forming apparatus

Abstract

To provide an external additive for toner that, even when particles of an organic silicon polymer are used, has excellent blade cleaning properties and is excellent in durable stability.SOLUTION: There is provided an external additive for toner. The external additive for toner is organic silicon polymer particles. When the number average particle diameter of primary particles of the external additive for toner measured by a scanning electron microscope is A (nm), and the number average particle diameter of the external additive for toner measured by a centrifugal sedimentation method is B (nm), the external additive for toner satisfies the following formula (1). (1) 1.5≤B / A≤3.0.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present disclosure relates to an external toner additive, a toner using the external toner additive for use in an electrophotographic system, and an image forming apparatus using the toner. [Background technology]

[0002] In recent years, as electrophotographic full-color copying machines have become widespread, there has been an increasing demand for toners used in electrophotography to meet the demands of high-speed printing and to have a longer life. Conventionally, silica has been widely used as an external additive in toner. For example, Patent Document 1 discloses an example in which highly hydrophobic spherical sol-gel silica particles are added to toner base particles to improve the charging stability of the toner. However, when printing low-density images over a long period of time or when printing images in a high-temperature, high-humidity environment, the toner comes into contact with components such as the carrier and is subjected to stress, causing the silica particles to become embedded in the toner particle surface. This significantly changes the toner surface condition, leaving room for improvement in terms of reduced toner adhesion, reduced fluidity, and charging stability. On the other hand, Patent Documents 2 and 3 disclose examples in which polyalkylsilsesquioxane microparticles are added to toner particles to improve the durability and stability of the toner. Polyalkylsilsesquioxane microparticles have lower hardness than inorganic external additives such as silica, and the difference in hardness between them and the toner particle surface is small, which prevents them from sinking into the toner particle surface during prolonged use. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2007-099582 [Patent Document 2] International Publication No. 2015 / 107961 [Patent Document 3] Japanese Patent Application Laid-Open No. 2018-004949 Summary of the Invention [Problem to be solved by the invention]

[0004] The toner to which the polyalkylsilsesquioxane fine particles are externally added can suppress the embedding of the external additive fine particles, and therefore can maintain good developability, transferability, and fluidity throughout long-term use. However, it was found that the use of polyalkylsilsesquioxane fine particles poses a problem in blade cleaning of the photoreceptor surface. This is thought to be because the polyalkylsilsesquioxane fine particles are spherical and have too high rolling properties, preventing the formation of a blocking layer by the external additive at the cleaning blade nip. The present disclosure provides an external toner additive that exhibits excellent blade cleaning properties and excellent durability and stability even when using organosilicon polymer particles, as well as a toner and an image forming device that use the external toner additive. [Means for solving the problem]

[0005] The present disclosure provides an external toner additive, the toner external additive is organosilicon polymer particles, The number average particle diameter of the primary particles of the external toner additive measured by a scanning electron microscope is defined as A (nm), The present invention relates to an external toner additive that satisfies the following formula (1), where B (nm) is the number average particle diameter of the external toner additive measured by centrifugal sedimentation method. 1.5≦B / A≦3.0 (1) [Effects of the Invention]

[0006] According to the present disclosure, it is possible to provide an external toner additive that has excellent blade cleaning properties and excellent durability and stability. DETAILED DESCRIPTION OF THE INVENTION

[0007] In the present disclosure, unless otherwise specified, the expressions "XX or more and YY or less" or "XX to YY" representing a numerical range mean a numerical range including the endpoints, that is, the lower limit and the upper limit. When numerical ranges are stated in stages, the upper and lower limits of each numerical range can be combined in any way.

[0008] According to the research conducted by the present inventors, the use of organosilicon polymer particles as an external toner additive can prevent the external additive from becoming embedded in the surface of the toner particles, and has been found to provide better durability and stability than the commonly used silica. Because silica is hard compared to toner particles, a hard object is pressed against a soft object, and silica tends to become embedded in the toner particle surface. On the other hand, organosilicon polymer particles are softer than silica and have an appropriate hardness, making it possible to prevent silica from becoming embedded in the toner particle surface. Furthermore, as a result of extensive research, the inventors have found that the use of the above external toner additives enables stable blade cleaning.

[0009] When the number average particle diameter of primary particles of an external toner additive that is an organosilicon polymer particle measured by a scanning electron microscope (SEM) is defined as A (nm) and the number average particle diameter measured by centrifugal sedimentation method (CPS) is defined as B (nm), the relationship 1.5≦B / A≦3.0 is satisfied. A B / A ratio of 1.5 or greater means that the organosilicon polymer particles have formed aggregates. To consistently prevent toner from slipping through during blade cleaning, it is believed that a blocking layer made of external additives must be formed near the cleaning blade nip. The properties of the external additive are important for the stable formation of this blocking layer. External additives with too high a slipperiness move too quickly and are not suitable for forming a blocking layer. The property required for external additives to form a blocking layer is cohesion, which suppresses the mutual movement of external additives when they come together. Even if the primary particle shape is highly slippery, such as spherical, by coagulating them with a relationship of B / A≧1.5, the rolling properties between external additives can be suppressed, allowing for the stable formation of a blocking layer.

[0010] On the other hand, if the cohesive force is too high and the number of external additives that slip through the cleaning blade nip is extremely reduced, the coefficient of friction with the photoreceptor surface at the blade nip becomes too high, which can cause the blade to chatter or turn up. For example, coagulated silica made by the calcination method is prone to this phenomenon. On the other hand, the external additives for toner do not aggregate as firmly as the aggregated silica. Therefore, when the coefficient of friction of the blade increases near the nip and the blade is caught in the nip, pressure is applied to the external additives closest to the nip, which causes the aggregates to break down and break down into particles equivalent to the primary particle size. The dispersed external additives pass through the blade nip appropriately, preventing excessive increases in the coefficient of friction, which is believed to enable stable cleaning. Only a small portion of the dispersed external additives remain in agglomerates, ensuring stable formation of the blocking layer.

[0011] Furthermore, the relationship between the number average particle diameter A (nm) and the number average particle diameter B (nm) of the primary particles must be B / A≦3.0. If B / A exceeds 3.0, the aggregates become too large, the blocking layer becomes coarse, and cleaning stability is lacking. In addition, when externally added, the toner particles It may become difficult to adhere the coating to the substrate, and a desirable coating state may not be achieved. B / A is preferably 1.7 or more and 2.5 or less, and more preferably 1.8 or more and 2.2 or less. The B / A ratio can be controlled by the organosilicon compound concentration and stirring conditions during the process of forming the organosilicon polymer particles. To increase the B / A ratio, for example, one method is to increase the organosilicon compound concentration and weaken the stirring force.

[0012] The number average particle size A (nm) of the primary particles of the organosilicon polymer particles is preferably 40≦A≦150, and more preferably 50≦A≦110. By setting the average particle size within the above range, the external additive is less likely to slip through the blade nip, which is advantageous for forming a blocking layer, resulting in better blade cleaning performance. If the average particle size of the primary particles is 40 nm or more, when the above-mentioned aggregates are broken up, the particle size does not become too small, and the amount that slips through the blade nip becomes appropriate, resulting in more stable cleaning performance. This is also preferable from the viewpoint of preventing the external additive from being buried. Also, by making A≦150, the amount of the aggregates that slips through the blade nip when they break up becomes appropriate, and a good coating state for the toner is easily obtained.

[0013] The number average particle size B (nm) measured by centrifugal sedimentation method (CPS) is preferably 80 nm or more and 350 nm or less, and more preferably 150 nm or more and 230 nm or less.

[0014] The Young's modulus of the organosilicon polymer particles is preferably 1000 MPa to 30,000 MPa, and more preferably 1400 MPa to 9,000 MPa. The yield stress of the organosilicon polymer particles is preferably 1000 MPa to 10,000 MPa, and more preferably 1100 MPa to 2,000 MPa. By keeping the Young's modulus within the above range, it is possible to prevent external additives from becoming embedded in the toner particle surface, resulting in superior durability and stability. The Young's modulus and yield stress of organosilicon polymer particles can be controlled by the number of reactive groups in the organosilicon polymer. The greater the proportion of tetrafunctional silanes in the organosilicon compounds used to produce the organosilicon polymer particles, the stronger the structure will be, and the higher these values ​​will be, while the greater the proportion of compounds with fewer reactive groups, the lower these values ​​will be.

[0015] The half-value width of the number particle size distribution of the organosilicon polymer particles, as measured by centrifugal sedimentation, is preferably 50 nm to 150 nm, more preferably 50 nm to 120 nm. By setting the half-value width to 50 nm or more, favorable cohesion properties of the external additive can be obtained. Furthermore, by setting the half-value width to 150 nm or less, the cohesion properties of the external additive and the ability of the external additive to pass through when dispersed are improved. The half-value width can be controlled by adjusting the concentration of the organosilicon compound during the process of forming the organosilicon polymer particles, and can also be increased by increasing the primary particle size of the organosilicon polymer particles.

[0016] The toner has toner particles containing a binder resin and an external additive, The external additive is preferably the above-mentioned external additive for toner. The content of the external toner additive is preferably 1.0 to 10.0 parts by mass, and more preferably 2.0 to 8.0 parts by mass, relative to 100 parts by mass of the toner particles. By setting the content within the above range, excellent blade cleaning properties and durability can be obtained. By setting the content to 1.0 part by mass or more, the amount of external additive necessary for forming the blocking layer can be reliably secured. Furthermore, by setting the content to 10.0 parts by mass or less, contamination of components by external additives can be suppressed, and good durability and stability can be obtained.

[0017] The coverage of the toner particles with the organosilicon polymer particles of the external toner additive is preferably 30% to 70% by area, and more preferably 45% to 60% by area. A coverage of 30% or more reduces the toner's adhesive force and provides excellent durability and stability. A coverage of 70% or less prevents excess external additive from being generated, preventing component contamination. The coverage can be controlled by the amount of organosilicon polymer particles added.

[0018] The adhesion rate of the external toner additive to the toner particles is preferably 30% to 80%, and more preferably 40% to 60%. By setting the adhesion rate to 30% or more, contamination of components can be further suppressed and better durability and stability can be obtained. Furthermore, by setting the adhesion rate to 80% or less, the amount of external additive required for forming the blocking layer can be more reliably secured. The adhesion rate can be controlled by the external addition conditions. The adhesion rate can be increased by increasing the rotation speed of the external addition device or by extending the external addition time. The adhesion rate can also be increased by heating during external addition.

[0019] There are no particular limitations on the image forming apparatus to which the toner can be applied. The above toner is preferably applied to an image forming apparatus having a cleaning member that removes the toner from an image bearing member (photosensitive member) that bears the toner. The cleaning member is preferably a blade formed of an elastic body, and the blade is pressed against the image carrier so as to swing about a swing fulcrum.

[0020] The cleaning blade can be supported by either a swinging type, in which the blade is pressed against the photosensitive member so that it swings around a swing fulcrum, or a fixed type, in which the blade does not swing. The swinging type is preferred to further improve toner slip-through. The swinging type increases the ability to follow the surface of the photosensitive member, improving cleaning performance against toner slip-through. The pressure of the cleaning blade on the image carrier is preferably 20 gf / cm or more and 40 gf / cm or less in terms of linear pressure on the image carrier. By setting it to 20 gf / cm or more, a cleaning blade nip is stably formed. Furthermore, by setting it to 40 gf / cm or less, wear / scratches on the photoreceptor are suppressed, resulting in a highly durable cleaning system.

[0021] The elastic material used for the blade is not particularly limited, and any known elastic material used for cleaning blades can be used, for example, a rubber blade. The image forming apparatus is not particularly limited in other configuration as long as it employs a blade as a cleaning member, and examples thereof include known image forming apparatuses that include an image carrier and a developing unit that forms a toner image on the surface of the image carrier.

[0022] <Method of manufacturing external toner additives> The toner external additive is an organosilicon polymer particle. The organosilicon polymer particle contains an organosilicon polymer. The organosilicon polymer has a structure in which silicon atoms and oxygen atoms are alternately bonded. The organosilicon polymer particle preferably contains 90% by mass or more of the organosilicon polymer based on the organosilicon polymer particle.

[0023] There are no particular restrictions on the method for producing organosilicon polymer particles, but for example, a silane compound can be added dropwise to water, hydrolyzed and condensed in the presence of a catalyst, and the resulting suspension can then be filtered and dried. The particle size can be controlled by the type of catalyst, the compounding ratio, the reaction initiation temperature, the addition time, etc. Examples of the catalyst include, but are not limited to, acidic catalysts such as hydrochloric acid, hydrofluoric acid, sulfuric acid, and nitric acid, and basic catalysts such as aqueous ammonia, sodium hydroxide, and potassium hydroxide.

[0024] The organosilicon polymer particles are preferably produced by the following method. Specifically, it is preferable that the method comprises a first step of obtaining a hydrolysate of an organosilicon compound such as an organotrialkoxysilane, a second step of mixing the hydrolysate with an alkaline aqueous medium and subjecting the hydrolysate to a polycondensation reaction, and a third step of mixing the polycondensation reaction product with an aqueous solution to form particles. In some cases, a hydrophobizing agent may be further added to the spherical organosilicon polymer particle dispersion to obtain hydrophobized spherical organosilicon polymer particles.

[0025] In the first step, an organosilicon compound such as organotrialkoxysilane is brought into contact with the catalyst in an aqueous solution of an acidic or alkaline substance dissolved in water by stirring, mixing, or the like. As the catalyst, known catalysts can be suitably used. Specifically, examples of the catalyst include acidic catalysts such as hydrochloric acid, hydrofluoric acid, sulfuric acid, and nitric acid, and examples of basic catalysts such as ammonia water, sodium hydroxide, and potassium hydroxide.

[0026] The amount of catalyst used may be adjusted appropriately depending on the type of organosilicon compound and catalyst. Preferably, the amount of catalyst used is 1×10 -3 The amount is selected in the range of 1 part by mass to 1 part by mass. The amount of catalyst used is 1×10 -3 If the amount of catalyst used is 1 part by mass or more, the reaction will proceed sufficiently. On the other hand, if the amount of catalyst used is 1 part by mass or less, the concentration of impurities remaining in the fine particles will be low, making hydrolysis easier. The amount of water used is preferably 2 to 15 moles per mole of organosilicon compound. If the amount of water is 2 moles or more, the hydrolysis reaction will proceed sufficiently, and if the amount is 15 moles or less, productivity will improve.

[0027] The reaction temperature is not particularly limited, and the reaction may be carried out at room temperature or under heated conditions. However, it is preferable to carry out the reaction at a temperature maintained at 10 to 60°C, since this allows a hydrolysate to be obtained in a short time and also makes it possible to suppress the partial condensation reaction of the produced hydrolysate. There are no particular restrictions on the reaction time, and it may be appropriately selected taking into consideration the reactivity of the organosilicon compound used, the composition of the reaction liquid obtained by mixing the organosilicon compound, acid, and water, and productivity.

[0028] In the second step of the method for producing organosilicon polymer particles, the raw material solution obtained in the first step is mixed with an alkaline aqueous medium to polycondense the particle precursor, thereby obtaining a polycondensation reaction solution. The alkaline aqueous medium is a liquid obtained by mixing an alkaline component, water, and, if necessary, an organic solvent. The alkaline component used in the alkaline aqueous medium is one whose aqueous solution is basic and acts as a neutralizer for the catalyst used in step 1 and as a catalyst for the polycondensation reaction in step 2. Examples of such alkaline components include alkali metal hydroxides such as lithium hydroxide, sodium hydroxide, and potassium hydroxide; ammonia; and organic amines such as monomethylamine and dimethylamine.

[0029] The amount of the alkali component used is an amount that neutralizes the acid and effectively acts as a catalyst for the polycondensation reaction. For example, when ammonia is used as the alkali component, the amount is usually selected in the range of 0.01 mass % or more and 12.5 mass % or less per 100 parts by mass of the mixture of water and the organic solvent. In the second step, in order to prepare an alkaline aqueous medium, an organic solvent may be used in addition to the alkaline component and water. The organic solvent is not particularly limited as long as it is compatible with water, but an organic solvent that dissolves 10 g or more of water per 100 g at room temperature and normal pressure is preferred.

[0030] Specifically, methanol, ethanol, n-propanol, 2-propanol, butanolic polyhydric alcohols such as ethylene glycol, diethylene glycol, propylene glycol, glycerin, trimethylolpropane, and hexanetriol; ethers such as ethylene glycol monoethyl ether, acetone, diethyl ether, tetrahydrofuran, and diacetone alcohol; and amide compounds such as dimethylformamide, dimethylacetamide, and N-methylpyrrolidone. Among the organic solvents listed above, alcohol solvents such as methanol, ethanol, 2-propanol, butanol, etc. are preferred. Furthermore, from the viewpoint of hydrolysis and dehydration condensation reactions, it is more preferred to select as the organic solvent the same alcohol as the alcohol produced by elimination.

[0031] In the third step, the polycondensation reaction product obtained in the second step is mixed with an aqueous solution and granulated. As the aqueous solution, water (tap water, pure water, etc.) can be suitably used, but water may further contain a component that is compatible with water, such as a salt, an acid, an alkali, an organic solvent, a surfactant, a water-soluble polymer, etc. The temperature of the polycondensation reaction liquid and the aqueous solution when they are mixed is not particularly limited, and is suitably selected in the range of 5 to 70°C in consideration of their composition, productivity, etc.

[0032] The polycondensation reaction product and the aqueous solution are mixed using a stirring blade or the like, and the B / A ratio can be controlled by the stirring force. Weakening the stirring force reduces the dispersibility of the polycondensation reaction product, allowing the B / A ratio to be increased. For example, when using a 2000 ml beaker scale, the preferred stirring force is 100 rpm to 1000 rpm using a 50 mm diameter propeller. Also, increasing the concentration of the polycondensation reaction product (organosilicon polymer) can control B / A to a larger value. The concentration of the polycondensation reaction product (organosilicon polymer) when mixed with the aqueous solution in the particulate formation step is preferably 3.5% to 10.0% by mass. A concentration of 3.5% by mass or higher makes it easier to achieve an aggregated state where B / A is greater than or equal to 1.5. On the other hand, by keeping the concentration at 10.0% by mass or lower, it is easier to control B / A to less than 3.0.

[0033] The organosilicon polymer particles can be recovered by any known method without any particular restrictions. For example, floating powder can be scooped out or filtration can be used, but filtration is preferred due to its simplicity of operation. The filtration method is not particularly limited, and a known apparatus such as vacuum filtration, centrifugal filtration, pressure filtration, etc. The filter paper, filter, filter cloth, etc. used in filtration are not particularly limited as long as they are industrially available, and may be appropriately selected depending on the apparatus used.

[0034] The organosilicon polymer particles may be surface treated with a known means such as a silane coupling agent or silicone oil to adjust the degree of hydrophobicity. The hydrophobicity of the organosilicon polymer particles is preferably 40 to 80%, more preferably 50 to 80%, from the viewpoint of obtaining a stable amount of triboelectric charge.

[0035] In order for the external toner additive to easily aggregate to some extent, the average circularity of the external toner additive is preferably 0.50 or more and less than 0.80, and more preferably 0.60 or more and 0.74 or less. The average circularity can be controlled by the stirring force during particle formation and the concentration of the organosilicon polymer. The average circularity was measured as follows:

[0036] The average circularity is calculated from the perimeter and projected area of ​​the organosilicon polymer particles by analyzing image data obtained by a field emission scanning electron microscope (S-4800, Hitachi High-Technologies Corporation) (FE-SEM) using image analysis software (ImageJ (developed by Wayne Rasband)). Specifically, the average circularity is calculated from the perimeter and projected area of ​​the organosilicon polymer particles by analyzing 100 particles obtained by the image analysis. Regarding this, the 50% circularity at a cumulative frequency of 50% of circularity calculated by the following formula is used. Circularity = 4π × (A / I 2 ) (In the formula, I represents the perimeter (nm) of the primary particle on the image, and A represents the projected area (nm 2 ) FE-SEM observation is performed with organosilicon polymer particles externally added to the toner particles.

[0037] The organosilicon polymer particles are preferably a condensation polymer of an organosilicon compound having a structure represented by the following formula (2).

[0038] [ka]

[0039] (In formula (2), R 2 , R 3 , R 4 and R 5each independently represents an alkyl group having 1 to 6 carbon atoms (preferably 1 to 3, more preferably 1 or 2), a phenyl group, or a reactive group (for example, a halogen atom, a hydroxy group, an acetoxy group, or an alkoxy group (preferably having 1 to 6 carbon atoms, more preferably 1 to 3 carbon atoms)).

[0040] To obtain organosilicon polymer particles, An organosilicon compound (tetrafunctional silane) having four reactive groups in one molecule of formula (2), R in equation (2) 2 is an alkyl group or a phenyl group, and three reactive groups (R 3 , R 4 , R 5 ) an organosilicon compound (trifunctional silane) having R in equation (2) 2 , R 3 is an alkyl group or a phenyl group, and two reactive groups (R 4 , R 5 ) an organosilicon compound (bifunctional silane) having R in equation (2) 2 , R 3 , R 4 is an alkyl group or a phenyl group, and one reactive group (R 5 ) can be used. It is preferable to use 50 mol % or more of a trifunctional silane as the organosilicon compound.

[0041] These reactive groups undergo hydrolysis, addition polymerization, and condensation polymerization to form crosslinked structures, resulting in organosilicon polymer particles. 3 , R 4 and R 5 The hydrolysis, addition polymerization, and condensation polymerization can be controlled by the reaction temperature, reaction time, reaction solvent, and pH.

[0042] Examples of tetrafunctional silanes include tetramethoxysilane, tetraethoxysilane, and tetraisocyanate silane.

[0043] Examples of trifunctional silanes include methyltrimethoxysilane, methyltriethoxysilane, methyldiethoxymethoxysilane, methylethoxydimethoxysilane, methyltrichlorosilane, methylmethoxydichlorosilane, methylethoxydichlorosilane, methyldimethoxychlorosilane, methylmethoxyethoxychlorosilane, methyldiethoxychlorosilane, methyltriacetoxysilane, methyldiacetoxymethoxysilane, methyldiacetoxyethoxysilane, methylacetoxydimethoxysilane, methylacetoxymethoxyethoxysilane, methylacetoxydiethoxysilane, methyltrihydroxysilane, methylmethoxydihydroxysilane, methylethoxydihydroxysilane, methyldimethoxyhydroxysilane, methylethoxymethoxyhydroxysilane, methyldiethoxyhydroxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, ethyltrichlorosilane, ethyltriacetoxysilane, ethyltrihydroxysilane, propyltrimethoxysilane, propyltriethoxysilane, propyltrichlorosilane, and propyltriacetoxysilane. butyltrimethoxysilane, butyltriethoxysilane, butyltrichlorosilane, butyltriacetoxysilane, butyltrihydroxysilane, hexyltrimethoxysilane, hexyltriethoxysilane, hexyltrichlorosilane, hexyltriacetoxysilane, hexyltrihydroxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, phenyltrichlorosilane, phenyltriacetoxysilane, and phenyltrihydroxysilane.

[0044] Examples of bifunctional silanes include di-tert-butyldichlorosilane, di-tert-butyldimethoxysilane, di-tert-butyldiethoxysilane, dibutyldichlorosilane, dibutyldimethoxysilane, dibutyldiethoxysilane, dichlorodecylmethylsilane, dimethoxydecylmethylsilane, diethoxydecylmethylsilane, dichlorodimethylsilane, dimethoxydimethylsilane, diethoxydimethylsilane, and diethyldimethoxysilane. Examples include orchids.

[0045] Examples of monofunctional silanes include t-butyldimethylchlorosilane, t-butyldimethylmethoxysilane, t-butyldimethylethoxysilane, t-butyldiphenylchlorosilane, t-butyldiphenylmethoxysilane, t-butyldiphenylethoxysilane, chlorodimethylphenylsilane, methoxydimethylphenylsilane, ethoxydimethylphenylsilane, chlorotrimethylsilane, methoxytrimethylsilane, ethoxytrimethylsilane, triethylmethoxysilane, triethylethoxysilane, tripropylmethoxysilane, tributylmethoxysilane, tripentylmethoxysilane, triphenylchlorosilane, triphenylmethoxysilane, and triphenylethoxysilane.

[0046] <Binder resin> The binder resin used in the toner is not particularly limited, and the following polymers can be used. Examples of suitable styrene copolymers include homopolymers of styrene and its substituted derivatives, such as polystyrene, poly-p-chlorostyrene, and polyvinyltoluene; styrene-p-chlorostyrene copolymers, styrene-vinyltoluene copolymers, styrene-vinylnaphthalene copolymers, styrene-acrylic acid ester copolymers, styrene-methacrylic acid ester copolymers, styrene-α-chloromethyl methacrylate copolymers, styrene-acrylonitrile copolymers, styrene-vinyl methyl ether copolymers, styrene-vinyl ethyl ether copolymers, styrene-vinyl methyl ketone copolymers, and styrene-acrylonitrile-indene copolymers; and polyvinyl chloride, phenolic resins, natural resin-modified phenolic resins, natural resin-modified maleic acid resins, acrylic resins, methacrylic resins, polyvinyl acetate, silicone resins, polyester resins, polyurethane resins, polyamide resins, furan resins, epoxy resins, xylene resins, polyvinyl butyral resins, terpene resins, coumarone-indene resins, and petroleum-based resins. Among these, polyester resins are preferred from the viewpoints of durability and charging stability.

[0047] <Coloring agent> The toner particles may contain a colorant. Examples of the colorant include the following: Examples of black colorants include carbon black, and those toned to black using a yellow colorant, a magenta colorant, and a cyan colorant. As the colorant, a pigment may be used alone, but it is more preferable to use a dye and a pigment in combination to improve the clarity from the viewpoint of the image quality of a full-color image. Examples of pigments for magenta toner include CI Pigment Red 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 21, 22, 23, 30, 31, 32, 37, 38, 39, 40, 41, 48:2, 48:3, 48:4, 49, 50, 51, 52, 53, 54, 55, 57: 1, 58, 60, 63, 64, 68, 81:1, 83, 87, 88, 89, 90, 112, 114, 122, 123, 146, 147, 150, 163, 184, 202, 206, 207, 209, 238, 269, 282; CI Pigment Violet 19; CI Bat Red 1, 2, 10, 13, 15, 23, 29, 35. Dyes for magenta toner include solvent dyes such as CI Solvent Red 1, 3, 8, 23, 24, 25, 27, 30, 49, 81, 82, 83, 84, 100, 109, and 121; CI Disperse Red 9; CI Solvent Violet 8, 13, 14, 21, and 27; and CI Disperse Violet 1; and basic dyes such as CI Basic Red 1, 2, 9, 12, 13, 14, 15, 17, 18, 22, 23, 24, 27, 29, 32, 34, 35, 36, 37, 38, 39, and 40; and CI Basic Violet 1, 3, 7, 10, 14, 15, 21, 25, 26, 27, and 28.

[0048] Examples of pigments for cyan toner include CI Pigment Blue 2, 3, 15:2, 15:3, 15:4, 16, and 17; CI Vat Blue 6; and CI Acid Blue 45, and copper phthalocyanine pigments having 1 to 5 phthalimidomethyl groups substituted on the phthalocyanine skeleton. An example of a dye for cyan toner is CI Solvent Blue 70. Yellow toner pigments include the following: CI Pigment Yellow 1, 2, 3, 4, 5, 6, 7, 10, 11, 12, 13, 14, 15, 16, 17, 23, 62, 65, 73, 74, 83, 93, 94, 95, 97, 109, 110, 111, 120, 127, 128, 129, 147, 151, 154, 155, 168, 174, 175, 176, 180, 181, 185; CI Vat Yellow 1, 3, 20. An example of a yellow toner dye is CI Solvent Yellow 162. The content of the colorant is preferably 0.1 parts by mass or more and 30 parts by mass or less with respect to 100 parts by mass of the binder resin.

[0049] (wax) The toner particles may contain wax. Examples of wax include the following. Hydrocarbon waxes such as microcrystalline wax, paraffin wax, and Fischer-Tropsch wax; oxides of hydrocarbon waxes such as oxidized polyethylene wax or their block copolymers; waxes whose main component is fatty acid esters such as carnauba wax; partially or completely deoxidized fatty acid esters such as deoxidized carnauba wax.

[0050] Further examples include saturated straight-chain fatty acids such as palmitic acid, stearic acid, and montanic acid; unsaturated fatty acids such as brassidic acid, eleostearic acid, and parinaric acid; saturated alcohols such as stearyl alcohol, aralkyl alcohol, behenyl alcohol, carnaubyl alcohol, ceryl alcohol, and melissyl alcohol; polyhydric alcohols such as sorbitol; fatty acids such as palmitic acid, stearic acid, behenic acid, and montanic acid and alcohols such as stearyl alcohol, aralkyl alcohol, behenyl alcohol, carnaubyl alcohol, ceryl alcohol, and melissyl alcohol. Esters with cholesters; fatty acid amides such as linoleic acid amide, oleic acid amide, and lauric acid amide; saturated fatty acid bisamides such as methylene bisstearic acid amide, ethylene biscapric acid amide, ethylene bislauric acid amide, and hexamethylene bisstearic acid amide; unsaturated fatty acid amides such as ethylene bisoleic acid amide, hexamethylene bisoleic acid amide, N,N'-dioleyl adipic acid amide, and N,N'-dioleyl sebacic acid amide; aromatic bisamides such as m-xylene bisstearic acid amide and N,N'-distearyl isophthalic acid amide; stearic acid Fatty metal salts such as calcium phosphate, calcium laurate, zinc stearate, and magnesium stearate (commonly known as metallic soaps); waxes grafted onto aliphatic hydrocarbon waxes using vinyl monomers such as styrene or acrylic acid; partial esters of fatty acids and polyhydric alcohols such as behenic acid monoglyceride; and methyl ester compounds with hydroxy groups obtained by hydrogenating vegetable oils and fats. The content of the wax is preferably 2.0 to 30.0 parts by mass with respect to 100 parts by mass of the binder resin.

[0051] (charge control agent) The toner particles may contain a charge control agent, if necessary. Although known charge control agents can be used, metal compounds of aromatic carboxylic acids are particularly preferred because they are colorless, can charge toner quickly, and can stably maintain a constant charge amount. Examples of negative charge control agents include metal salicylate compounds, metal naphthoate compounds, metal dicarboxylate compounds, polymeric compounds having sulfonic acid or carboxylic acid on the side chain, polymeric compounds having sulfonate salts or sulfonate esters on the side chain, polymeric compounds having carboxylate salts or carboxylate esters on the side chain, boron compounds, urea compounds, silicon compounds, and calixarenes. The charge control agent may be added internally or externally to the toner particles. The amount of the charge control agent added is preferably 0.2 to 10 parts by mass with respect to 100 parts by mass of the binder resin.

[0052] (Inorganic fine particles) In addition to the external additive for toner described above, other inorganic fine particles may also be used in combination with the toner, if necessary. The inorganic fine particles may be internally added to the toner particles or may be mixed with the toner particles as an external additive. As the external additive, inorganic fine particles such as silica are preferred. The inorganic fine particles are preferably hydrophobized with a hydrophobizing agent such as a silane compound, silicone oil, or a mixture thereof.

[0053] As an external additive, 2 / g or more 400m 2 / g or less is preferred. By using inorganic fine particles with a specific surface area in the above range in combination, it is possible to fine-tune the flowability and chargeability. The effects of the organosilicon polymer particles are not affected even when inorganic fine particles are used in combination. The inorganic fine particles are preferably used in an amount of 0.1 parts by mass or more and 10.0 parts by mass or less per 100 parts by mass of toner particles. The content of the external toner additives described above is preferably 50% by mass to 100% by mass, more preferably 80% by mass to 100% by mass, and even more preferably 90% by mass to 100% by mass, of the total amount of external additives.

[0054] <Developer> The toner can be used as a one-component developer, but in order to further improve dot reproducibility and to provide stable images over a long period of time, it is preferable to mix the toner with a magnetic carrier and use it as a two-component developer. That is, it is preferable that the developer is a two-component developer containing a toner and a magnetic carrier, and the toner is the above-mentioned toner. Examples of magnetic carriers include surface-oxidized iron powder, unoxidized iron powder, metal particles such as iron, lithium, calcium, magnesium, nickel, copper, zinc, cobalt, manganese, chromium, and rare earth elements, alloy particles thereof, and oxide particles thereof; magnetic materials such as ferrite, and materials containing magnetic materials and binder resins that hold the magnetic materials in a dispersed state. Generally known carriers such as magnetic material dispersed resin carriers (so-called resin carriers) can be used. The mixing ratio of the magnetic carrier and the toner is preferably such that the toner concentration in the two-component developer is 2% by mass or more and 15% by mass or less, more preferably 4% by mass or more and 13% by mass or less.

[0055] <Method of manufacturing toner particles> The method for producing the toner particles is not particularly limited, and known production methods such as suspension polymerization, emulsion aggregation, melt-kneading, and dissolution suspension methods can be used. The toner particles thus obtained are mixed with the above-mentioned external additive for toner and, if necessary, other external additives to obtain a toner. To mix the toner particles and external additives, a mixing device such as a double cone mixer, a V-type mixer, a drum mixer, a super mixer, a Henschel mixer, a Nauta mixer, a Mechano Hybrid (manufactured by Nippon Coke and Engineering Co., Ltd.), or a Nobilta (manufactured by Hosokawa Micron Corporation) can be used.

[0056] The Young's modulus of the toner particles is preferably 2000 MPa to 9000 MPa from the viewpoint of the durability stability and charging stability of the toner. The yield stress of the toner particles is preferably 500 MPa to 10,000 MPa from the viewpoint of the durability stability and charging stability of the toner.

[0057] The methods for measuring various physical properties are explained below. <Method for measuring number average particle size A of primary particles of external toner additives> The number average particle diameter A of the primary particles of the external toner additive can be determined by measurement using a scanning electron microscope "S-4800" (trade name; manufactured by Hitachi, Ltd.). From the image of the external additive particles, 100 organosilicon polymer particles are randomly selected, the major axis of the primary particles of the fine particles is measured, and the arithmetic mean value is taken as the number-average particle size of the primary particles. The magnification for observation can be adjusted appropriately depending on the size of the organosilicon polymer particles. (If the toner contains other external additives) The number average particle size A from the toner can also be measured by the above method, but if the toner contains external additives other than the organosilicon polymer, the organosilicon polymer particles are separated and measured using the following method. When the toner contains silicon-containing materials other than organosilicon polymer particles, EDS analysis is performed on each particle of the external additive during toner observation, and the presence or absence of an Si element peak is used to determine whether the analyzed particle is an organosilicon polymer particle. When a toner contains both organosilicon polymer particles and silica microparticles, the organosilicon polymer particles are identified by comparing the ratio of the Si and O elemental contents (atomic %) (Si / O ratio) with a standard sample. EDS analysis is performed on both the organosilicon polymer particles and the silica microparticle samples under the same conditions to obtain the Si and O elemental contents (atomic %). The Si / O ratio of the organosilicon polymer particles is designated A, and the Si / O ratio of the silica microparticles is designated B. Measurement conditions are selected such that A is significantly greater than B. Specifically, 10 measurements are performed on the standard sample under the same conditions, and the arithmetic mean of A and B is obtained. Measurement conditions are selected such that the resulting average A / B is greater than 1.1. If the Si / O ratio of the particle to be judged is on the A side of [(A+B) / 2], the particle is judged to be an organosilicon polymer particle. Tospearl 120A (Momentive Performance Materials Japan, LLC) was used as a sample of organosilicon polymer particles, and HDK V15 (Asahi Kasei) was used as a sample of silica microparticles.

[0058] <Method for measuring number average particle size B of external toner additives by centrifugal sedimentation method> The number-average particle size B of the toner external additive particles is determined by centrifugal sedimentation. Specifically, 0.01 g of dried external additive particles is placed in a 25 ml glass vial, and 0.2 g of a 5% Triton solution and 19.8 g of RO water are added to prepare a solution. Next, the probe (the tip of the tip) of the ultrasonic disperser is immersed in the above solution, and ultrasonic dispersion is performed at an output of 20 W for 15 minutes to obtain a dispersion. The number average particle size was measured using a centrifugal sedimentation particle size distribution analyzer DC24000 manufactured by Instruments. The disk rotation speed was set to 18,000 rpm, and the true density was 1.3 g / cm. 3 Before measurement, the instrument is calibrated using polyvinyl chloride particles with an average particle size of 0.476 μm.

[0059] (Calculation of half-value width of number particle size distribution) The half-value width can be calculated from the number particle size distribution obtained by the above measurement, with the horizontal axis representing particle size and the vertical axis representing number frequency. When the peak number frequency is fmax, the width of the particle size at fmax / 2 is the half-value width.

[0060] (Separation of external additives from toner) Various physical properties can also be measured using the external additive separated from the toner by the following method. 1 g of toner is added to 31 g of chloroform in a vial and dispersed. The dispersion is processed for 30 minutes using an ultrasonic homogenizer to create a dispersion liquid. The processing conditions are as follows: Ultrasonic treatment device: Ultrasonic homogenizer VP-050 (manufactured by Taitec Co., Ltd.) Microchip: Stepped microchip, tip diameter φ2mm Microchip tip position: Center of glass vial, 5 mm above the bottom of the vial Ultrasonic conditions: intensity 30%, 30 minutes. During this time, ultrasonic waves are applied while cooling the vial with ice water to prevent the dispersion from heating up. The dispersion was transferred to a glass tube (50 mL) for a swing rotor and centrifuged in a centrifuge (H-9R; manufactured by Kokusan Co., Ltd.) for 58.33 s. -1 The mixture is centrifuged for 30 minutes. After centrifugation, the toner is separated into its constituent materials in the glass tube. The external additives are extracted and the mixture is dried under vacuum conditions (40°C / 24 hours).

[0061] <Confirmation of the Structure of Organosilicon Polymer Particles> The composition and ratio of the constituent compounds of organosilicon polymer particles (external toner additives) are identified using pyrolysis gas chromatography mass spectrometry (hereafter referred to as pyrolysis GC / MS) and NMR. Pyrolysis GC / MS is used to analyze the types of compounds that make up organosilicon polymer particles. By analyzing the mass spectrum of the components of the decomposition products derived from organosilicon polymer particles that are produced when organosilicon polymer particles are thermally decomposed at approximately 550°C to 700°C, the types of constituent compounds of the organosilicon polymer particles can be identified.

[0062] [Pyrolysis GC / MS measurement conditions] Pyrolysis device: JPS-700 (Japan Analysis Industry) Decomposition temperature: 590℃ GC / MS equipment: Focus GC / ISQ (Thermo Fisher) Column: HP-5MS, length 60 m, inner diameter 0.25 mm, film thickness 0.25 μm Inlet temperature: 200℃ Flow pressure: 100kPa Split: 50mL / min MS ionization: EI Ion source temperature: 200℃ Mass Range 45-650 The ratio of the constituent compounds of the identified organosilicon polymer particles was then calculated using a solid 29 Measured and calculated by Si-NMR. solid 29 In Si-NMR, peaks are detected in different shift regions depending on the structure of the functional groups that bond to Si in the constituent compounds of the organosilicon polymer particles. The structure of the functional group of each peak can be identified using a standard sample, and the abundance ratio of each constituent compound can be calculated from the peak area obtained. solid 29 The measurement conditions for Si-NMR are, for example, as follows: Equipment: JNM-ECX5002 (JEOL RESONANCE) Temperature: room temperature Measurement method: DDMAS method 29 Si 45° Sample tube: zirconia 3.2 mm diameter Sample: Filled in powder form into a test tube Sample rotation speed: 10kHz Relaxation delay: 180s Scan:2000

[0063] After this measurement, the chloroform-insoluble portion of the organosilicon polymer particles is divided into multiple silane components with different substituents and bonding groups, and the peak areas are calculated by curve fitting to separate the peaks into the following X1, X2, X3, and X4 structures. X1 structure: (Ri)(Rj)(Rk)SiO 1 / 2 (A1) X2 structure: (Rg)(Rh)Si(O 1 / 2 )2(A2) X3 structure: RmSi(O 1 / 2 )3(A3) X4 structure: Si(O 1 / 2 )4(A4) [ka]

[0064] In the formulae (A1), (A2), and (A3), Ri, Rj, Rk, Rg, Rh, and Rm represent silicon-bonded organic groups such as hydrocarbon groups having 1 to 6 carbon atoms, halogen atoms, hydroxy groups, acetoxy groups, or alkoxy groups. In addition, the hydrocarbon group bonded to Si is 13 Confirm by C-NMR. << 13 C-NMR (solid state) measurement conditions≫ Equipment: JEOL RESONANCE JNM-ECX500II Sample tube: 3.2 mm diameter Sample: Filled in powder form into a test tube Measurement temperature: room temperature Pulse mode: CP / MAS Measurement nuclear frequency: 123.25MHz ( 13 C) Reference substance: Adamantane (external standard: 29.5ppm) Sample rotation speed: 20kHz Contact time: 2ms Delay time: 2 seconds Number of times accumulated: 1024 In this method, methyl groups (Si-CH3), ethyl groups (Si-C2H5), propyl groups (Si-C3H7), butyl groups (Si-C4H9), pentyl groups (Si-C5H 11 ), hexyl group (Si-CH 13 The presence or absence of signals due to phenyl groups (Si-C6H5) or other hydrocarbon groups is confirmed. If you need to check the structure in more detail, 13 C-NMR and 29 Along with the Si-NMR measurement results 1 It may also be identified by the results of H-NMR measurement.

[0065] <Method for measuring the softening temperature (Tm) of binder resin> The softening temperature of a resin is measured using a constant-load extrusion capillary rheometer, the "Flow Tester CFT-500D Flow Property Evaluation Device" (Shimadzu Corporation), according to the manual that comes with the device. With this device, a constant load is applied from above the measurement sample using a piston, while the measurement sample filled in a cylinder is heated and melted, and the molten measurement sample is extruded from a die at the bottom of the cylinder, allowing a flow curve to be obtained that shows the relationship between the piston's descending distance and temperature. In this disclosure, the attached "Flow characteristic evaluation device Flow Tester CFT-500D" The "melting temperature in the 1 / 2 method" described in the manual is taken as the softening temperature (Tm). The melting temperature in the 1 / 2 method is calculated as follows. First, calculate half the difference between the amount of piston descent when the outflow ends (end of outflow, Smax) and the amount of piston descent when the outflow starts (lowest point, Smin) (this is called X; X = (Smax - Smin) / 2). Then, determine the melting temperature in the 1 / 2 method as the temperature on the flow curve when the amount of piston descent is the sum of X and Smin.

[0066] The measurement sample is prepared by compressing approximately 1.0 g of resin at 25°C using a tablet press (e.g., a standard manual Newton press NT-100H, manufactured by NPA Systems Co., Ltd.) at 10 MPa for 60 seconds to form a cylindrical sample with a diameter of 8 mm. The specific procedures for measurement are carried out according to the manual that comes with the device. The measurement conditions for the CFT-500D are as follows: Test mode: Temperature rising method Starting temperature: 50℃ Achieved temperature: 200℃ Measurement interval: 1.0℃ Heating rate: 4.0℃ / min Piston cross-sectional area: 1.000cm 2 Test load (piston load): 10.0 kgf (0.9807 MPa) Preheat time: 300 seconds Die hole diameter: 1.0mm Die length: 1.0mm

[0067] <Method for measuring weight average particle size (D4) of toner particles> The weight-average particle size (D4) of the toner particles is measured with an effective number of 25,000 measurement channels using a precision particle size distribution measuring device equipped with a 100 μm aperture tube and using the narrow-pore electrical resistance method, the Coulter Counter Multisizer 3 (registered trademark, manufactured by Beckman Coulter, Inc.), and the accompanying dedicated software for setting measurement conditions and analyzing measurement data, the Beckman Coulter Multisizer 3 Version 3.51 (manufactured by Beckman Coulter, Inc.), and the measurement data is analyzed and calculated. The aqueous electrolyte solution used for the measurement is prepared by dissolving special grade sodium chloride in ion-exchanged water to a concentration of approximately 1% by mass, such as "ISOTON II" (manufactured by Beckman Coulter). Before carrying out the measurements and analysis, the dedicated software is set up as follows. In the "Change Standard Measurement Method (SOM)" screen of the dedicated software, set the total count in control mode to 50,000 particles, the number of measurements to 1, and the Kd value to the value obtained using "Standard Particle 10.0 μm" (Beckman Coulter). Press the threshold / noise level measurement button to automatically set the threshold and noise level. Also, set the current to 1600 μA, the gain to 2, the electrolyte to ISOTON II, and check "Flush aperture tube after measurement." In the dedicated software's "Pulse to particle size conversion setting screen," 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 or more and 60 μm or less.

[0068] The specific measurement method is as follows. (1) Pour approximately 200 ml of the electrolyte solution into a 250 ml round-bottom glass beaker made specifically for the Multisizer 3, set it on the sample stand, and stir the stirrer rod counterclockwise at 24 revolutions per second. Then, use the "aperture tube flush" function of the dedicated software to remove any dirt and air bubbles from inside the aperture tube. (2) Approximately 30 ml of the above-mentioned aqueous electrolyte solution is placed in a 100 ml flat-bottom glass beaker, and approximately 0.3 ml of a dilution obtained by diluting "Contaminon N" (a 10% by weight aqueous solution of a neutral detergent for cleaning precision measuring instruments, pH 7, consisting of a nonionic surfactant, anionic surfactant, and organic builder, manufactured by Wako Pure Chemical Industries, Ltd.) three times by weight with ion-exchanged water is added as a dispersant. (3) A predetermined amount of ion-exchanged water is placed in the water tank of an ultrasonic disperser, "Ultrasonic Dispersion System Tetora150" (manufactured by Nikkaki Bios Co., Ltd.), which has two built-in oscillators with an oscillation frequency of 50 kHz and a phase difference of 180 degrees and an electrical output of 120 W, and approximately 2 ml of the Contaminon N is added to this water tank. (4) Set the beaker (2) in the beaker fixing hole of the ultrasonic disperser, operate the ultrasonic disperser, and adjust the height of the beaker so that the resonance state of the liquid surface of the electrolytic solution in the beaker is maximized. (5) While ultrasonic waves are irradiated to the electrolyte solution in the beaker in (4), approximately 10 mg of toner particles are added little by little to the electrolyte solution and dispersed. The ultrasonic dispersion process is then continued for another 60 seconds. During the ultrasonic dispersion, the water temperature in the water tank is appropriately adjusted to be between 10°C and 40°C. (6) Using a pipette, the electrolytic solution (5) containing the dispersed toner is dropped into the round-bottom beaker (1) placed in the sample stand, and the measurement concentration is adjusted to approximately 5%. Then, measurements are continued until the number of particles measured reaches 50,000. (7) The measurement data is analyzed using the dedicated software provided with the device, and the weight-average particle size (D4) is calculated. Note that when the dedicated software is set to Graph / Volume %, the "Average diameter" on the Analysis / Volume Statistics (Arithmetic Mean) screen is the weight-average particle size (D4).

[0069] <Method for measuring coverage> The toner surface image taken with a scanning electron microscope "S-4800" (product name; manufactured by Hitachi, Ltd.) is analyzed using image analysis software Image-Pro Plus ver. 5.0 (Nippon Roper Co., Ltd.) to calculate the coverage. The imaging conditions for the S-4800 are as follows: (1) Sample preparation Apply a thin layer of conductive paste to a sample stage (aluminum sample stage 15 mm x 6 mm), then spray toner onto it. Then, use air to remove excess toner from the sample stage and allow it to dry thoroughly. Place the sample stage in the sample holder and adjust the sample stage height to 36 mm using the sample height gauge. (2) S-4800 observation condition setting Pour liquid nitrogen into the anti-contamination trap attached to the S-4800 housing until it overflows, and leave it for 30 minutes. Start the "PC-SEM" of the S-4800 and Perform flushing (cleaning of the FE chip, which is the electron source). Click the accelerating voltage display area on the control panel on the screen and press the [Flushing] button to open the flushing execution dialog. Confirm that the flushing intensity is 2 and execute. Confirm that the emission current due to flushing is 20-40 μA. Insert the sample holder into the sample chamber of the S-4800 case. Press [Origin] on the control panel to move the sample holder to the observation position. Click the accelerating voltage display to open the HV setting dialog, and set the accelerating voltage to [1.1 kV] and the emission current to [20 μA]. In the [Basic] tab of the operation panel, set the signal selection to [SE], select [Upper (U)] and [+BSE] for the SE detector, and select [LA100] in the selection box to the right of [+BSE] to set the mode for observation using backscattered electron images. Also in the [Basic] tab of the operation panel, set the probe current in the electron optical system condition block to [Normal], the focus mode to [UHR], and the WD to [4.5 mm]. Press the [ON] button in the accelerating voltage display on the control panel to apply the accelerating voltage.

[0070] (3) Calculation of the number average particle size (D1) of the toner Drag within the magnification display area on the control panel to set the magnification to 5000 (5k). Rotate the focus knob [COARSE] on the operation panel to achieve a certain degree of focus, then adjust the aperture alignment. Click [Align] on the control panel to display the alignment dialog, and select [Beam]. Rotate the STIGMA / ALIGNMENT knobs (X, Y) on the operation panel to move the displayed beam to the center of the concentric circles. Next, select [Aperture], and rotate the STIGMA / ALIGNMENT knobs (X, Y) one by one to stop the image movement or adjust it so that it moves as little as possible. Close the aperture dialog, and use autofocus to adjust the focus. Repeat this operation twice more to adjust the focus. Thereafter, the particle diameters of 300 toner particles are measured to determine the number average particle diameter (D1). The particle diameter of each particle is the maximum diameter observed when the toner particles are observed.

[0071] (4) Focus adjustment For the particles with a number average particle diameter (D1) of ±0.1 μm obtained in (3), align the midpoint of the maximum diameter with the center of the measurement screen, and drag within the magnification display section of the control panel to set the magnification to 10,000 (10k) times. Rotate the focus knob [COARSE] on the operation panel to adjust the aperture alignment once the image is in focus to a certain extent. Click [Align] on the control panel to display the alignment dialog and select [Beam]. Rotate the STIGMA / ALIGNMENT knobs (X, Y) on the operation panel to move the displayed beam to the center of the concentric circle. Next, select [Aperture] and turn the STIGMA / ALIGNMENT knobs (X, Y) one by one to stop the image movement or adjust it to minimize the movement. Close the aperture dialog and use autofocus to adjust the focus. After that, set the magnification to 50,000 (50k) and adjust the focus using the focus knob and STIGMA / ALIGNMENT knob as above, then use autofocus again to focus. Repeat this operation to adjust the focus. Here, if the tilt angle of the observation surface is large, the accuracy of the coverage measurement is likely to be low, so when adjusting the focus, select an object that brings the entire observation surface into focus at the same time, and select an object with as little surface tilt as possible for analysis.

[0072] (5) Save image Adjust the brightness in ABC mode, take a photo with a size of 640 x 480 pixels, and save it. Use this image file to perform the following analysis. Take one photo for each toner. The image is taken for 25 particles of toner.

[0073] (6) Image analysis The image obtained using the above method is binarized using the following analysis software to calculate the coverage. At this time, the above screen is divided into 12 squares and each is analyzed. The analysis conditions for the image analysis software Image-Pro Plus ver. 5.0 are as follows: Select "Count / Size" from "Measurement" on the toolbar, then "Options" to set the binarization conditions. Select 8 connectivity in the object extraction options and set smoothing to 0. In addition, do not select pre-sort, fill holes, or encompass lines, and set "Exclude borders" to "None." Select "Measurement items" from "Measurement" on the toolbar and set the area selection range to 2-10 7 Enter: The coverage rate is calculated by enclosing a square area. The area (C) of the area should be 24,000 to 26,000 pixels. Automatic binarization is performed using "Processing" - Binarization, and the total area of ​​areas without organosilicon polymer particles (D) is calculated. The coverage rate can be calculated using the following formula from the area of ​​the square region C and the total area of ​​the regions without organosilicon polymer particles D. Coverage rate (%)=100-(D / C×100) The arithmetic mean value of all the data obtained is taken as the coverage rate.

[0074] <Method for measuring adhesion rate> The adhesion rate is determined by performing a water washing process and evaluating the amount of external additive particles remaining on the toner particle surface after washing. Specifically, the coverage rate of the toner before and after washing is calculated, [Toner coverage rate after washing] / [Toner coverage rate before washing]×100 is defined as the "adhesion rate (%)." (Water washing process) Weigh out 20 g of a 30% by weight aqueous solution of "Contaminon N" (a neutral detergent for cleaning precision measuring instruments, consisting of a nonionic surfactant, an anionic surfactant, and an organic builder, with a pH of 7) into a 50 mL vial and mix it with 1 g of toner. The mixture is placed in a KM Shaker (model V.SX) manufactured by Iwaki Sangyo Co., Ltd., and shaken for 120 seconds at a speed of 50. Depending on the adhesion state of the organosilicon polymer particles, this may cause the organosilicon polymer particles to migrate from the toner particle surface to the dispersion liquid. Then, the mixture was centrifuged using a centrifuge (H-9R; manufactured by Kokusan Co., Ltd.) (16.67 S -1 The toner is separated from the organosilicon polymer particles that have migrated to the supernatant liquid by heating at 400°C for 5 minutes. The precipitated toner is dried by vacuum drying (40°C / 24 hours) and then washed with water to obtain the toner.

[0075] <Method for measuring Young's modulus and yield stress of toner external additive particles and toner particles> The Young's modulus and yield stress of toner external additive particles and toner particles are determined by microcompression tests using a Hysitron PI 85L Pico Indenter (manufactured by BRUKER). Young's modulus (MPa) is calculated from the slope of the profile (stress-strain curve) of the displacement (nm) and test force (μN) obtained from the measurement. The yield stress (MPa) is calculated by dividing the stress applied to the measuring indenter at the yield point by the area of ​​the measuring surface of the measuring indenter. Equipment and fixtures Base system: Hysitron PI-85L Measurement indenter: Flat-end indenter with a circular tip and a diameter of 1 μm SEM used: Thermo Fisher Versa 3D SEM conditions: -10°tilt, 13pA at 10keV Measurement conditions Measurement mode: Displacement control Maximum displacement: 30nm Displacement speed: 1 nm / sec Hold time: 2 seconds Unloading speed: 5nm / sec ·Analysis method Hertz analysis is applied to the obtained load-displacement curve when compressed from 0 nm to 10 nm, and the Young's modulus and yield stress of each particle are calculated. Sample preparation A silicon wafer onto which external toner additives or toner particles are attached. [Example]

[0076] The present invention will be described in more detail with reference to the following examples, which, however, are not intended to limit the scope of the present invention. Unless otherwise specified, the "parts" in the following formulations are all by weight.

[0077] <Production Example of Toner Additive Particles 1> 1. Hydrolysis process 43.0 g of RO water and 0.008 g of acetic acid as a catalyst were placed in a 200 ml beaker and stirred at 45° C. 54.0 g of trimethoxymethylsilane was added thereto and stirred for 1.5 hours to obtain a raw material solution.

[0078] 2. Polycondensation process An alkaline aqueous medium was prepared by adding 70.0 g of RO water, 340.0 g of methanol, and 1.8 g of 25% aqueous ammonia to a 1000 ml beaker and stirring at 30°C. The raw material solution obtained in step 1, Hydrolysis, was added dropwise to this alkaline aqueous medium over 1 minute. After the dropwise addition of the raw material solution, the mixture was stirred for 1.5 hours while maintaining the temperature at 30°C, allowing the polycondensation reaction to proceed and producing a polycondensation reaction liquid.

[0079] 3.Particleization process 700 g of RO water was placed in a 2000 ml beaker, and the polycondensation reaction liquid obtained in 2. Polycondensation step was added dropwise over 10 minutes while stirring at 25° C. A 50 mm diameter propeller was used for stirring, with a rotation speed of 200 rpm. The polycondensation reaction mixture immediately became cloudy upon mixing with water, yielding a dispersion containing organosilicon polymer particles having siloxane bonds.

[0080] 4. Hydrophobization process 23 g of hexamethyldisilazane as a hydrophobizing agent was added to the dispersion containing the organosilicon polymer particles having siloxane bonds obtained in the granulation step, and the mixture was stirred for 2.5 hours at 60°C. After leaving the mixture to stand for 5 minutes, the powder that had settled to the bottom of the solution was collected by suction filtration and dried under reduced pressure at 120°C for 24 hours to obtain external toner additive particles 1. The number average particle size A of the primary particle size of the obtained external toner additive particles 1 measured by SEM was 90 nm. The number average particle size B measured by centrifugal sedimentation method was 180 nm. The physical properties of external toner additive particles 1 are shown in Table 1.

[0081] <Production Example of Toner Additive Particles 2> Except for changing the dropping time in the granulation step to 30 minutes, external toner additive particles 2 were obtained in the same manner as in the production example of external toner additive particles 1. The physical properties of the obtained external toner additive particles 2 are shown in Table 1.

[0082] <Production Example of Toner Additive Particles 3> Except for changing the amount of RO water used in the granulation step to 500 g, the same procedure as in the production example of external toner additive particles 1 was carried out to obtain external toner additive particles 3. The physical properties of the obtained external toner additive particles 3 are shown in Table 1.

[0083] <Production Example of Toner Additive Particles 4> In the hydrolysis step, 54.0 g of trimethoxymethylsilane was replaced with 42.0 g of trimethoxymethylsilane and 12.0 g of dimethyldimethoxysilane, and the same procedure as in the production example of external toner additive particles 1 was repeated to obtain external toner additive particles 4. The physical properties of the obtained external toner additive particles 4 are shown in Table 1.

[0084] <Production Example of Toner Additive Particles 5> In the hydrolysis step, 54.0 g of trimethoxymethylsilane was changed to 42.0 g of trimethoxymethylsilane and 12.0 g of tetraethoxysilane, and the same procedure as in the production example of external toner additive particles 1 was repeated to obtain external toner additive particles 5. The physical properties of the obtained external toner additive particles 5 are shown in Table 1.

[0085] <Production Example of Toner Additive Particles 6> Except for changing the amount of 25% aqueous ammonia used in the polycondensation step to 1.4 g, the same procedure as in the production example of external toner additive particles 1 was carried out to obtain external toner additive particles 6. The physical properties of the obtained external toner additive particles 6 are shown in Table 1.

[0086] <Production Example of Toner Additive Particles 7> Except for changing the amount of 25% aqueous ammonia used in the polycondensation step to 2.5 g, the same procedure as in the production example of external toner additive particles 1 was carried out to obtain external toner additive particles 7. The physical properties of the obtained external toner additive particles 7 are shown in Table 1.

[0087] <Production Example of Toner Additive Particles 8> Except for changing the amount of RO water used in the granulation step to 900 g and changing the dropping time to 30 minutes, the same procedure as in the production example for toner external additive particles 1 was carried out to obtain toner external additive particles 8. The physical properties of the obtained toner external additive particles 8 are shown in Table 1.

[0088] <Production Example of Toner Additive Particles 9> Except for changing the amount of RO water used in the granulation step to 400 g, the same procedure as in the production example of external toner additive particles 1 was carried out to obtain external toner additive particles 9. The physical properties of the obtained external toner additive particles 9 are shown in Table 1.

[0089] <Production Example of Toner Additive Particles 10> Except for changing the amount of 25% aqueous ammonia used in the condensation polymerization step to 1.3 g, the same procedure as in the production example of external toner additive particles 1 was carried out to obtain external toner additive particles 10. The physical properties of the obtained external toner additive particles 10 are shown in Table 1.

[0090] <Production Example of Toner Additive Particles 11> Except for changing the amount of 25% aqueous ammonia used in the polycondensation step to 2.8 g, the same procedure as in the production example of external toner additive particles 1 was carried out to obtain external toner additive particles 11. The physical properties of the obtained external toner additive particles 11 are shown in Table 1.

[0091] <Production Example of Toner Additive Particles 12> The amount of RO water used in the granulation process was changed to 1200g, and the dripping time was changed to 30 minutes. Other than the above changes, the procedure was the same as in the production example of external toner additive particles 1 to obtain external toner additive particles 12. The physical properties of the obtained external toner additive particles 12 are shown in Table 1.

[0092] <Production Example of Toner Additive Particles 13> Except for changing the amount of RO water used in the granulation step to 1100 g and changing the dropping time to 20 minutes, the same procedure as in the production example of external toner additive particles 1 was carried out to obtain external toner additive particles 13. The physical properties of the obtained external toner additive particles 13 are shown in Table 1.

[0093] <Production Example of Toner Additive Particles 14> Except for changing the amount of RO water used in the granulation step to 400 g and changing the dropping time to 8 minutes, the same procedure as in the production example of external toner additive particles 1 was carried out to obtain external toner additive particles 14. The physical properties of the obtained external toner additive particles 14 are shown in Table 1.

[0094] <Production Example of Toner Additive Particles 15> The amount of 25% aqueous ammonia used in the polycondensation step was changed to 2.5 g. In addition, the amount of RO water used in the granulation step was changed to 1000 g, and the dropping time was changed to 20 minutes. Except for this, the same procedure as in the production example of external toner additive particles 1 was carried out to obtain external toner additive particles 15. The physical properties of the obtained external toner additive particles 15 are shown in Table 1.

[0095] <Production Example of Toner Additive Particles 16> The amount of 25% aqueous ammonia used in the polycondensation step was changed to 1.4 g. In addition, the amount of RO water used in the granulation step was changed to 400 g, and the dropping time was changed to 8 minutes. Except for this, the same procedure as in the production example of external toner additive particles 1 was carried out to obtain external toner additive particles 16. The physical properties of the obtained external toner additive particles 16 are shown in Table 1.

[0096] [Table 1]

[0097] <Production Example of Polyester Resin A1> 76.9 parts (0.167 moles) of polyoxypropylene(2.2)-2,2-bis(4-hydroxyphenyl)propane Terephthalic acid (TPA) 25.0 parts (0.145 moles) Adipic acid 8.0 parts (0.054 moles) Titanium tetrabutoxide 0.5 parts The above materials were placed in a 4-liter, four-necked glass flask, which was then fitted with a thermometer, a stirring rod, a condenser, and a nitrogen inlet tube and placed in a mantle heater. The atmosphere in the flask was then replaced with nitrogen gas, and the temperature was gradually raised with stirring until the mixture was allowed to react for 4 hours at 200°C. Thereafter, 1.2 parts (0.006 mol) of trimellitic anhydride (TMA) was added and the mixture was reacted at 180°C for 1 hour to obtain polyester resin A1. The softening temperature of this polyester resin A1 was 90°C.

[0098] <Production Example of Polyester Resin A2> 71.3 parts (0.155 moles) of polyoxypropylene(2.2)-2,2-bis(4-hydroxyphenyl)propane Terephthalic acid 24.1 parts (0.145 moles) Titanium tetrabutoxide 0.6 parts The above materials were placed in a 4-liter, four-necked glass flask, which was then fitted with a thermometer, a stirring rod, a condenser, and a nitrogen inlet tube and placed in a mantle heater. The atmosphere in the flask was then replaced with nitrogen gas, and the temperature was gradually raised with stirring until the mixture was allowed to react at 200°C for 2 hours. Thereafter, 5.8 parts (0.030 mol %) of trimellitic anhydride was added and the mixture was reacted at 180°C for 10 hours to obtain polyester resin A2. The softening temperature of this polyester resin A2 was 130°C.

[0099] <Production Example of Toner Particle 1> Polyester resin A1 70.0 parts Polyester resin A2 30.0 parts Fischer-Tropsch wax (maximum endothermic peak temperature 78°C) 5.0 parts CI Pigment Blue 15:3 5.0 parts 0.1 parts of 3,5-di-t-butylsalicylic acid aluminum compound The raw materials shown in the above recipe were mixed in a Henschel mixer (FM-75, manufactured by Nippon Coke and Engineering Co., Ltd.) at a rotation speed of 20 s -1 After mixing for 5 minutes, the mixture was kneaded in a twin-screw kneader (PCM-30, manufactured by Ikegai Corporation) set at 125°C and 300 rpm. The resulting mixture was cooled and coarsely crushed to a diameter of 1 mm or less using a hammer mill. The resulting coarsely crushed material was then finely crushed in a mechanical crusher (T-250, manufactured by Freund Turbo Corporation). Further, classification was carried out using a rotary classifier (200TSP, manufactured by Hosokawa Micron Corporation) to obtain toner particles 1. The operating conditions of the rotary classifier (200TSP, manufactured by Hosokawa Micron Corporation) were a classification rotor rotation speed of 50.0 s -1 The resulting toner particles 1 had a weight average particle size (D4) of 6.2 μm, a Young's modulus of 4000 MPa, and a yield stress of 1000 MPa.

[0100] <Toner 1 manufacturing example> 100 parts of toner particles Toner additive particles 1 5.0 parts The above materials were mixed in a Henschel mixer FM-10C (Mitsui Miike Chemical Engineering Co., Ltd.) at a rotation speed of 65 s -1 The mixture was mixed at a rotation time of 10 minutes to obtain Toner 1. The coverage rate of the external additive on the toner particle surface was 55 area %, and the adhesion rate of the external additive was 50%.

[0101] <Production example of toners 2 to 24> Toners 2 to 24 were obtained in the same manner as in the production example of Toner 1, except that the external toner additive particles, addition amounts, and external addition conditions were changed to those shown in Table 2. The coverage rate and fixation rate of each toner are shown in Table 2.

[0102] [Table 2]

[0103] <Carrier 1 manufacturing example> Number average particle size: 0.30 μm, magnetization strength: 65 Am under a magnetic field of 1000 / 4π (kA / m) 2 / kg) of magnetite 1 Number average particle size: 0.50 μm, magnetization strength: 65 Am under a magnetic field of 1000 / 4π (kA / m) 2 / kg) magnetite2 To 100 parts of each of the above materials, 4.0 parts of a silane compound (3-(2-aminoethylaminopropyl)trimethoxysilane) was added, and the mixture was mixed and stirred at high speed in a container at 100° C. or higher to treat each of the fine particles. Phenol: 10% by weight Formaldehyde solution: 6% by mass (40% by mass of formaldehyde, 10% by mass of methanol, 50% by mass of water) Magnetite treated with the above silane compound 1:58 mass% Magnetite treated with the above silane compound 2: 26 mass% 100 parts of the above material, 5 parts of a 28% by weight aqueous ammonia solution, and 20 parts of water were placed in a flask, and the mixture was heated to 85°C over 30 minutes and maintained at that temperature while stirring and mixing. The polymerization reaction was carried out for 3 hours, resulting in hardening of the resulting phenolic resin. The hardened phenolic resin was then cooled to 30°C, and water was added. The supernatant was removed, and the precipitate was washed with water and air-dried. This was then dried under reduced pressure (5 mmHg or less) at 60°C to obtain magnetic material-dispersed spherical carrier 1. The volume-based 50% particle size (D50) was 34.2 μm.

[0104] <Manufacturing example of two-component developer 1> To 92.0 parts of Carrier 1, 8.0 parts of Toner 1 were added and mixed in a V-type mixer (V-20, manufactured by Seishin Enterprises) to obtain Two-Component Developer 1.

[0105] <Production examples of two-component developers 2 to 24> Two-component developers 2 to 24 were obtained by carrying out the same production procedure as in the production example of two-component developer 1, except that the toner was changed as shown in Table 3. [Table 3]

[0106] Example 1 The two-component developer 1 was evaluated as follows. As the image forming apparatus, a modified Canon imageRUNNER ADVANCE C5560 digital commercial printing printer was used, and two-component developer 1 was placed in the cyan position developer, and cleaning performance was evaluated.

[0107] Here, the discharge current amount in the primary charging process was 100 μA (the definition of discharge current is described in JP 2009-128842 A). The photosensitive drum used had a taper wear amount of 0.5 mg (the method for measuring taper wear amount is described in JP 2009-128842 A), and the photosensitive drum surface had Rz = 1.0 μm and Sm = 50 μm. The surface roughness of the photosensitive drum was measured as follows using a contact-type surface roughness measuring instrument (product name: Surfcorder SE3500, manufactured by Kosaka Laboratory Co., Ltd.).

[0108] The detector was a diamond stylus with an R of 2 μm and a force of 0.7 mN, the filter was 2CR, the cutoff value was 0.8 mm, the measurement length was 2.5 mm, and the feed rate was 0.1 mm, and the data was processed to obtain the 10-point average roughness Rz defined in JIS standard B0601. The average spacing Sm of the surface irregularities was measured under the same conditions and is the arithmetic mean value obtained from the following formula.

number

[0109] Examples of surface roughening means for controlling the surface shape of the photosensitive drum include, but are not limited to, abrasive sheets and abrasive grinding. The cleaning performance was evaluated under the following conditions.

[0110] <Cleaning evaluation condition 1> Environment 23℃5%RH The discharge current for the primary charging process is 100 μA. Cleaning blade setting angle 20° Cleaning blade support method: Oscillating type, spring pressure 700gf Cleaning blade pressure (linear pressure) against the photosensitive drum: 30gf / cm Amount of toner applied to the photosensitive drum: 0.3 to 0.4 mg / cm 2 Toner charge 35~50μC / g Under the above conditions, untransferred toner equivalent to 10 sheets of A3 paper was supplied to the cleaning blade at a process speed of 260 mm / sec, and then the blade was stopped, and the amount of toner that slipped through the cleaning blade was measured. The amount of toner that slipped through was estimated from the reflection density using X Rite by taping the photoreceptor. The evaluation criteria are as follows: The evaluation results are shown in Table 3. A: Reflection density less than 0.010 B: Reflection density is 0.010 or more and less than 0.015 C: Reflection density is 0.015 or more and less than 0.020 D: Reflection density is 0.020 or more

[0111] <Cleaning evaluation condition 2> Environment 30℃80%RH The discharge current for the primary charging process is 100 μA. Cleaning blade setting angle 20° Cleaning blade support method: Oscillating type, spring pressure 700gf Cleaning blade pressure (linear pressure) against the photosensitive drum: 30gf / cm Amount of toner applied to the photosensitive drum: 0.3 to 0.4 mg / cm 2 Toner charge amount 20~40μC / g Under the above conditions, 10 A3 solid images were printed at a process speed of 260 mm / sec. Then, 100 A3 solid white images were printed, and the level of cleaning failure (toner slip-through) occurring on the solid white images was evaluated. The evaluation criteria are as follows: The evaluation results are shown in Table 4. A: Minor streak defects 0-3 pieces B: 4 to 7 small streak defects C: Minor streak defects 8 to 10 pieces Or 1 to 3 streak defects of several centimeters D: 11 or more small streak defects Or 4 or more streak defects of several centimeters Or the blade is curled up

[0112] Cleaning rating 1 is an evaluation under strict conditions for slip-through under low humidity conditions. Cleaning evaluation 2 is an evaluation under strict conditions of high temperature and high humidity to prevent chattering / turning up of the cleaning blade. The oscillating cleaning blade support method increases its ability to follow the surface of the photoreceptor. This improves cleaning performance against slip-through particles, but on the other hand, if the coefficient of friction between the photoreceptor and the blade increases suddenly, the blade may be pulled in the direction of travel toward the photoreceptor surface, causing the blade to curl up. The evaluation results are shown in Table 4.

[0113] <Examples 2 to 24> The cleaning blade settings and the developers used in each example are shown in Table 4. Table 4 also shows the evaluation results.

[0114] <Comparative Examples 1 to 5> The cleaning blade settings and the developers used in each comparative example are shown in Table 4. Table 4 also shows the evaluation results.

[0115] [Table 4]

[0116] As a result of the evaluation, the toner of the present disclosure achieved excellent cleaning properties as shown in Table 4.

Claims

1. An external additive for toner, the toner external additive is organosilicon polymer particles, The number average particle diameter of the primary particles of the external toner additive measured by a scanning electron microscope is defined as A (nm), When the number average particle diameter of the external toner additive measured by centrifugal sedimentation method is B (nm), the following formula (1) is satisfied: 1.5≦B / A≦3.0 (1) The organosilicon polymer particles are a condensation polymer containing at least 50 mol % of a trifunctional silane having a structure represented by the following formula (2): (wherein R 2 is an alkyl group or a phenyl group; R 3 , R 4 and R 5 are reactive groups, and the reactive groups are any functional groups selected from the group consisting of a halogen atom, a hydroxy group, an acetoxy group and an alkoxy group.

2. 2. The external toner additive according to claim 1, wherein the number average particle diameter A (nm) satisfies the relationship 40≦A≦150.

3. 3. The external toner additive according to claim 1, wherein the Young's modulus of the external toner additive is 1,000 MPa to 30,000 MPa.

4. 4. The external toner additive according to claim 1, wherein the external toner additive has a yield stress of 1,000 MPa to 10,000 MPa.

5. 5. The external toner additive according to claim 1, wherein the half width of the number particle size distribution of the external toner additive measured by centrifugal sedimentation is 50 nm or more and 150 nm or less.

6. 6. The external toner additive according to claim 1, wherein the average circularity of the external toner additive is 0.50 or more and less than 0.

80.

7. The external toner additive according to claim 1, wherein the trifunctional silane is trimethoxymethylsilane.

8. The organosilicon polymer particles comprising: (i) a silicon dioxide particle; (i) a condensation polymer of trimethoxymethylsilane, (ii) a condensation polymer of trimethoxymethylsilane and dimethyldimethoxysilane; (iii) a condensation polymer of trimethoxymethylsilane and tetraethoxysilane; 8. The external toner additive according to claim 1, which is a condensation polymer of any one of the following:

9. A toner having toner particles containing a binder resin and an external additive, A toner, wherein the external additive is the external toner additive according to any one of claims 1 to 8.

10. 10. The toner according to claim 9, wherein the content of the external toner additive is 1.0 part by mass to 10.0 parts by mass with respect to 100 parts by mass of the toner particles.

11. 11. The toner according to claim 9, wherein the coverage of the external toner additive with respect to the toner particles is 30% by area or more and 70% by area or less.

12. 12. The toner according to claim 9, wherein the adhesion rate of the external toner additive to the toner particles is 30% or more and 80% or less.

13. 1. An image forming apparatus having a cleaning member that removes toner from an image carrier that carries the toner, The toner is the toner according to any one of claims 9 to 12, the cleaning member is a blade formed of an elastic material, the blade is brought into contact with the image carrier with a pressure force so as to swing about a swing fulcrum; The pressure is a linear pressure on the image carrier of 20 gf / cm or more and 40 gf / cm or less.

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