JP2019028122A - toner - Google Patents

Abstract

To provide a toner which has good fogging in a long-term use and reduces member contamination, and can suppress electrostatic off-set.SOLUTION: A toner contains toner base particles containing a binder resin, amorphous polyester and a colorant, where the binder resin contains a vinyl resin, an average white part area ratio obtained by subjecting the toner base particles observed with a scanning electron microscope (SEM) to binarization treatment on the following conditions is 10% or less, and a theoretical specific surface area A (m/g) obtained from number-based particle size distribution and true density of the toner base particles and a specific surface area B (m/g) measured by a BET method satisfy the following expression (1): 0.450≤B≤1.500 and expression (2): 1.23≤B/A≤1.60. How to determine white part area ratio: [Photographic condition] scanning electron microscope: S-4800, photographic magnitude: 2,000 times, photographic image: SE image, acceleration voltage: 2.0 kV, acceleration current: 10.0 μA, probe current: Normal, focus mode: UHR, and WD: 5.0 mm. [Area ratio measurement condition] white part area ratio in particle size 50% square with a center of gravity of the toner as a center is calculated by using image processing software Image J, wholly blackening background of a photographic image and then subjecting the photographic image to binarization processing.SELECTED DRAWING: None

Description

  The present invention relates to a toner used in an electrophotographic image forming method for developing an electrostatic image.

In recent years, the usage of copiers and printers has changed from one person to another, so there is a need to achieve further miniaturization as well as long life and high image quality. In addition, the area where printers are used is becoming more diverse than before, and it must be usable without problems in any environment.
To reduce the size, it is effective to reduce the size of the process cartridge in which the developer is accommodated and the size of the fixing device attached to the main body. One effective means for reducing the size of the process cartridge is, for example, the adoption of a cleanerless system. The cleanerless system can greatly contribute to downsizing of the main body because there is no cleaning blade or waste toner box.
In the cleanerless system, the transfer residual toner passes through the charging step, is collected in the toner container, and is sent to the developing step again. Therefore, compared to a system with a cleaning blade, the traveling distance of one toner particle becomes longer, and the stress applied to the toner becomes larger. Therefore, toner particles are brittlely broken and cracked due to stress accumulation in the toner during long-term use. In addition, the toner particles may be deformed such that the hardness of the toner particles is crushed by the load from the member, and the toner particles may remain in the cartridge as irregularly shaped particles. Such irregularly shaped particles are difficult to be uniformly charged by rubbing or the like, and may become a “fogging” component that is developed in a non-image area on the electrostatic latent image carrier.
Further, when the transfer residual toner is sent to the charging member, the charging member may be contaminated by the external additive coated on the toner or toner base particles. As a result, it becomes difficult for the electrostatic latent image carrier to maintain a desired charging performance through long-term use, and image defects may occur.
As described above, in order to solve the problems caused by the downsizing of the main body, it is necessary to suppress fogging by reducing irregularly shaped particles and to suppress charging member contamination due to a free external additive or the like.
Various toner improvement methods have been proposed for these problems.
Patent Document 1 proposes a method for producing toner base particles having high circularity in order to make the charge amount distribution uniform in addition to a sharp particle size distribution. This technique has a step of forming droplets of a polymerizable monomer composition, and a step of polymerizing the polymerizable monomer composition to obtain toner mother particles. An aqueous medium containing is used. By using an aqueous medium containing a dispersion stabilizer also in the polymerization step, toner base particles having a high degree of circularity are obtained.
Further, Patent Document 2 proposes that inorganic fine particles are internally added in advance and unevenly distributed on the surface, thereby imparting appropriate irregularities to the base surface to improve transferability and cleaning properties.
In Patent Document 3, in a toner base particle containing a binder resin containing a noncrystalline resin (A) and an amorphous polyester resin (B) and a colorant, in a matrix phase containing the noncrystalline resin (A). Describes a toner in which an amorphous polyester resin (B) is dispersed as a domain phase. It is described that the number average domain diameter has a specific range of size in the observed image of the cross section of the toner base particles.
In Patent Document 4, two or more types of resin particles are used to heat and agglomerate using the difference in glass transition temperature of each resin to obtain toner base particles in which irregularities derived from the resin particles are formed on the surface of the toner base particles. ing.

Japanese Patent No. 3972709 JP 2006-184746 A Japanese Patent Laying-Open No. 2015-152703 Japanese Patent No. 4485382

However, in Patent Document 1, when an aqueous medium containing a dispersion stabilizer is used in the polymerization step, toner base particles with high circularity are surely obtained, irregularly shaped particles are reduced, and the chargeability of one toner particle is uniform. There is a possibility that fogging after black will improve. However, since the surface of the toner base particles is smooth, it may be disadvantageous for fixing large external particle additives such as spacer particles, and as a result, there is a possibility that charging member contamination cannot be suppressed.
Further, in Patent Document 2, because of the toner base particle manufacturing method that involves volume shrinkage at the time of solvent removal, there may be a large amount of irregularly shaped particles, and considering the application of a cleanerless system, toner cracking may occur easily. There is sex. In addition, a desired uneven shape may not be provided, and it may be difficult to achieve both suppression of charging member contamination and suppression of fog.
Regarding Patent Document 3, when a cleaner-less system is employed, the charge amount may decrease in the latter half of durability because the external additive may be embedded in the polyester portion deposited on the surface layer. In addition, the toner may be cracked and broken, and the fog may not be suppressed.
Further, in Patent Document 4, since the toner constituent material having a different glass transition temperature is heated and aggregated to give the surface of the toner base particles an uneven shape, it may not be possible to provide a desired uneven size. In addition, it may be difficult to reduce irregularly shaped particles in the toner base particle manufacturing method using heat aggregation, and considering application to a one-component contact developing cleaner-less, toner cracking is likely to occur, or uniform charging becomes difficult. there is a possibility.
From the above, assuming future miniaturization of the main body, there is still room for improvement in order to achieve suppression of fog and reduction of contamination of the charging member by reducing irregular shaped particles.
An object of the present invention is to provide a toner that solves the above problems.
That is, an object of the present invention is to provide a toner capable of reducing good fog characteristics and charging member contamination over a long period of use under any use environment.

The present invention is a toner having toner base particles containing a binder resin, an amorphous polyester and a colorant,
The binder resin contains a vinyl resin,
The toner has an average circularity of 0.960 or more,
The average white area area ratio obtained by binarizing the toner base particles observed with a scanning electron microscope (SEM) under the following conditions is 10.0% or less,
The theoretical specific surface area A (m ² / g) obtained from the particle size distribution and true density of the toner base particles and the specific surface area B (m ² / g) measured by the BET method are expressed by the following formula (1). ) And (2).
0.450 ≦ B ≦ 1.500 (1)
1.23 ≦ B / A ≦ 1.60 (2)
How to find the white area ratio [Shooting conditions]
Scanning electron microscope: S-4800
Magnification: 2000 times Image: SE image Acceleration voltage: 2.0 kV
Acceleration current: 10.0 μA
Probe current: Normal
Focus mode: UHR
WD: 5.0mm
[Area ratio measurement conditions]
Image processing software: Image J is used to binarize the background of the photographed image after making it completely black, and the white area ratio in 50% of the particle diameter is calculated around the center of gravity of the toner.

  According to the present invention, it is possible to obtain a toner capable of reducing favorable fog characteristics and charging member contamination over a long period of use under any use environment.

It is a figure which shows an example of a developing device. 1 is a diagram illustrating an example of an image forming apparatus. 2 is an example of a developing device in which a magnet is disposed inside a toner carrier. It is an example of the white part area ratio calculation method. It is the graph which showed the transmittance | permeability with respect to methanol concentration.

  As described above, the downsizing required for printers in recent years includes, for example, removal of a cleanerless system and a fixing bias mechanism.

  Considering the cleanerless system, since the untransferred toner is reused, the number of rubbing times between the toner carrier and the regulating blade increases, and the toner deterioration is promoted. That is, the toner base particles are cracked or crushed, the particle size distribution is widened, and it is difficult to uniformly charge by rubbing between the toner carrier and the blade.

  This cracking of the toner mother particles is likely to occur when there are irregularly shaped particles such as two by one particles or spindle-shaped particles. The reason is as follows.

  First, every two particles, but since the resin part that connects the two particles is thin, we believe that it will break easily due to external stress. In addition, it is assumed that a deformed toner such as a spindle-shaped toner has a poor rolling property and thus a load due to external stress occurs locally.

  On the other hand, the collapse of the toner particles occurs remarkably when the hardness of the toner base particles is low.

  In addition, fogging, which is a phenomenon in which toner having a low charge amount is developed into a non-image area (white image portion) on the electrostatic latent image carrier after passing a solid black image, is caused by such cracking and crushing of the toner. (Fog after black) is likely to occur. This fog phenomenon remarkably occurs in a low temperature and low humidity environment. This is considered to be due to the fact that the stress applied to the toner passing between the charging roller, the toner carrier, and the regulating blade increases greatly due to the increased hardness of the member.

  Therefore, in order to suppress the toner breakage and crushing, it is necessary to reduce the irregularly shaped particles of the toner and to increase the hardness. By doing so, it is possible to obtain a toner that suppresses post-black fogging in a low temperature and low humidity environment.

  Conventionally, as a technique for suppressing irregularly shaped particles while increasing the toner hardness, that is, a technique for obtaining a toner having a high degree of circularity, a suspension polymerization method can be mentioned.

  The suspension polymerization toner mainly has a structure in which a shell portion has a high softening point material and a core portion has a low softening point material or a plasticizer such as a release agent. However, when used for a long time with an image forming apparatus that is subject to stress on the toner, such as a cleaner-less system, even if the shell has a high softening point material, the core may be soft, or the toner may collapse. It was difficult to improve the toner deterioration.

  On the other hand, by obtaining a toner with a high degree of circularity by suspension polymerization, cracking of the toner is suppressed, and uniform charging is effective. However, in consideration of the long life in recent years, a large particle size external additive is often used as a spacer particle. However, when a large particle size external additive is used for such a high-circularity toner, the surface of the toner base particle is reduced. Due to the smoothness, there is a possibility that the fixation is insufficient. As a result, the initial charging performance of the toner may not be maintained. In addition, when a cleaner-less system is employed for downsizing, external additive contamination of the charging member may become more prominent. When the charging member is contaminated by the external additive, the charging performance is deteriorated at the contaminated portion of the charging member, and there is a possibility that image defects such as image density unevenness may occur.

  When the contact charging mechanism is used, this charging member contamination is considered to be more conspicuous in a high-temperature and high-humidity environment where the charging roller is soft and contaminants are likely to adhere.

  As described above, when considering the application of a one-component contact development cleaner-less system, it is currently difficult to increase the hardness of the toner and reduce irregular particles while at the same time suppressing contamination of the charging member due to external additives. It was.

  As a result of detailed studies by the present inventors, it has been found that the following items must be satisfied in order to solve the above problems.

That is, a toner having toner base particles containing a binder resin, amorphous polyester and a colorant, the binder resin containing a vinyl resin,
The toner has an average circularity of 0.960 or more,
From the toner base particles observed with a scanning electron microscope (SEM), the average white area area ratio obtained by binarizing under the following conditions is 10% or less,
The number-based particle size distribution of the toner base particles, the theoretical specific surface area A obtained from the true density,
The toner is characterized in that the specific surface area B measured by the BET method satisfies the following formulas (1) and (2).
0.450 ≦ B ≦ 1.500 (1)
1.23 ≦ B / A ≦ 1.60 (2)
How to find the white area ratio [Shooting conditions]
Scanning electron microscope: S-4800
Magnification: 2000 times Image: SE image Acceleration voltage: 2.0 kV
Acceleration current: 10.0 μA
Probe current: Normal
Focus mode: UHR
WD: 5.0mm
[Area ratio measurement conditions]
Image processing software: Image J is used to binarize the background of the photographed image after making it completely black, and the white area ratio in 50% of the particle diameter is calculated around the center of gravity of the toner.

  The present invention will be described in detail below.

  First, the toner of the present invention is a toner having toner base particles containing a binder resin, amorphous polyester, and a colorant, and the binder resin contains a vinyl resin.

  By having the vinyl resin, for example, maintenance of the rigidity and viscosity of the toner can be easily achieved, and cracking and crushing of the toner can be suppressed. By having amorphous polyester, toner particles with few irregular shaped particles can be obtained. For example, when producing toner particles by suspension polymerization, the reason is not clear, but having a polyester resin improves the dispersibility of the colorant in the polymerizable monomer composition in the granulation step and the polymerization step. Thus, it is considered that the particles of the polymerizable monomer composition are stabilized in the aqueous medium. Thereby, the coalescence of the particles is suppressed, and it is considered that toner particles with few irregularly shaped particles can be obtained.

  Further, the shape of the toner surface can be controlled by the presence ratio of the vinyl resin and the amorphous polyester in the toner, and the suppression of fogging can be further improved.

  Further, it is important for the toner of the present invention that the average circularity is 0.960 or more and 1.000 or less in order to suppress the breakage of the toner base particles and to control the extremely fine surface shape of the toner.

  When the average circularity of the toner is 0.960 or more, the toner has a spherical shape or a shape close to it, and it is easy to obtain a uniform triboelectric chargeability with excellent fluidity, thereby suppressing fogging and electrostatic offset. . Further, in the circularity distribution of the toner, if the mode circularity is 0.98 or more, the above action becomes more remarkable, which is very preferable.

  If it is less than 0.960, it is difficult to achieve both white area ratio and surface roughness index, and it is impossible to achieve both suppression of fog and electrostatic offset and suppression of charging member contamination.

  The white area ratio is a numerical value of the particle surface shape when the toner is viewed macroscopically. As a result of investigations by the present inventors, when the white area ratio is high, that is, when irregularities that can be easily observed with an SEM (submicron) are formed on the surface of the toner base particles, the latter half of the durability in a low-temperature and low-humidity environment. It turned out that fogging at the site worsens. The reason is not clear, but I think as follows.

  For example, considering the generation of toner base particles in the suspension polymerization method, the polymerizable monomer composition that finally becomes toner base particles repeats coalescence, shearing, and coalescence in the granulation step. Of these two phenomena, when shearing occurs more easily than coalescence, fine particles are likely to be generated. When the fine particles are generated, the dispersant for stably presenting the polymerizable monomer composition as oil droplets in the aqueous medium is deprived of the fine particles. As a result, there is not enough dispersant to stabilize the oil droplets of the toner particle size, and unevenness of about submicron is formed on the toner base particles. As described above, the toner base particles thus prepared lack sufficient dispersant to stabilize the oil droplets of the toner particle diameter, so that it is easy to obtain irregular particles such as one by one or a spindle shape. Accordingly, when considering long-term use as a result, the toner is likely to crack, the fluidity is deteriorated, the uniform chargeability is deteriorated, the saturation charge amount is lowered, and the fog is deteriorated.

  As a result of further studies by the present inventors, it has been found that when the white area ratio exceeds 10.0%, the post-black fogging and electrostatic offset in the latter half of the durability in a low temperature and low humidity environment deteriorate.

  In order to set the white area ratio to 10.0% or less, it is preferable to control the acid value and the hydroxyl value of the amorphous polyester resin. Moreover, it has a process which mixes the particle | grains of the polymerizable monomer composition obtained by the granulation process, and a 2nd aqueous medium, and it is preferable that this 2nd aqueous medium contains a dispersion stabilizer. By containing the dispersion stabilizer in the second aqueous medium, it is possible to compensate for the dispersion stabilizer that is insufficient at the time of granulation and to further reduce the white area ratio. Further, it is more preferable that sodium chloride is contained in the first aqueous medium in the granulation step based on the polymerizable monomer composition. By containing a large amount of sodium chloride in the aqueous medium, it is possible to prevent the monomer of the polymerizable monomer from dissolving in the aqueous medium from the particles of the polymerizable monomer composition due to the salting out effect. As a result, the generation of emulsified particles can be easily suppressed, and irregular particles such as two by one are hardly generated. The white area ratio is preferably 9.0% or less, and more preferably 7.0% or less.

The toner of the present invention has a theoretical specific surface area A (m ² / g) obtained from the particle size distribution and true density of the toner base particles, and a specific surface area B (m ² / g) measured by the BET method. The toner satisfies the following expressions (1) and (2).
0.450 ≦ B ≦ 1.500 (1)
1.23 ≦ B / A ≦ 1.60 (2)

  This B / A (hereinafter referred to as the surface irregularity index) is a value calculated from the BET specific surface area measured by the BET multipoint method. is there. Therefore, the unevenness | corrugation which is not reflected in the white part area rate mentioned above is also included. The theoretical specific surface area A is a numerical value when all the particles are true spheres. Therefore, as B / A increases from 1.00, the unevenness is formed on the particle surface. As a result of studies by the present inventors, it has been found that, by imparting such extremely fine irregularities to the surface of the toner base particles, a good halftone image can be obtained through durability in a high temperature and high humidity environment. The reason for this is not clear, but I think as follows.

  In the case of cleanerless, the external additive remaining on the electrostatic latent image carrier after the toner transfer passes through the charging member and the toner carrier. At this time, most of the external additive contaminates the charging member, but when the uneven shape of the same size as the external additive is given to the toner, the external additive can be scraped off by the convex portion. I believe. As a result, it is considered that a good halftone image having no density unevenness is obtained.

  Further, it was found that when the white area ratio is 10.0% or less and the above formulas (1) and (2) are satisfied, the white fogging under a high temperature and high humidity environment is improved. The reason is not clear, but I guess as follows.

  First, fogging after white is a phenomenon in which toner having a low charge amount is developed in a non-image area (white image portion) on the electrostatic latent image carrier after passing a solid white image. It is. This phenomenon is caused by the fact that the charge stored in the toner leaks to the electrostatic latent image carrier side at the contact portion between the electrostatic latent image carrier and the toner carrier in the one-component contact development method. I think there is.

  At this time, if the surface of the toner base particles is not provided with an uneven shape of about submicron, and an uneven shape of nano order is provided, the electrostatic latent image has sufficient rolling properties to ensure the charge amount. The contact area with the image carrier can be reduced. As a synergistic effect, we believe that both high saturation charge and leak resistance can be achieved. As a result, it is considered that the fogging after white was improved.

  If the surface irregularity index is less than 1.23, it is difficult to maintain the charging performance of the charging member through durability, probably because the irregularities sufficient to scrape off the external additive are not formed. As a result, density unevenness occurs in the halftone image, and the contact area between the latent electrostatic image bearing member and the toner bearing member increases, resulting in deterioration of fogging after white. On the other hand, when the surface irregularity index exceeds 1.60, the fluidity of the toner is deteriorated, the uniform chargeability is deteriorated, and the fogging after black in a low temperature and low humidity environment is deteriorated.

  In order to make the surface irregularity index within the above range, a method of controlling the interfacial tension of oil droplets in an aqueous medium of an amorphous polyester resin and containing hydrophobized magnetic fine particles as a colorant is preferable. . A more preferable range of the surface unevenness index is 1.23 or more and 1.45 or less, and by controlling within this range, it is very easy to achieve both improvement in fog in a low temperature and low humidity environment and improvement in fog in a high temperature and high humidity environment.

  As described above, by satisfying these characteristics, it is possible to obtain a toner that has good fog characteristics over a long period of use in any use environment and that suppresses charging member contamination.

  Further, from the viewpoint of easy suppression of toner cracking, the toner aspect ratio is more preferably 0.910 or more. A high aspect ratio means that the toner base particles are less spherical and have a more spherical shape. When it is 0.910 or more, toner cracking is dramatically suppressed throughout the durability, and post-black fogging is improved.

  Further, it is preferable that the softening point of the toner is 115 ° C. or more and 140 ° C. or less because both the fixability and the suppression of toner collapse can be easily achieved.

  Next, the binder resin used in the present invention will be described.

  The binder resin of the toner contains a vinyl resin. In addition to the vinyl resin, a known resin used as a binder resin may be used to the extent that the effects of the present invention are not impaired. The binder resin is preferably a vinyl resin.

  As described above, vinyl resin can easily achieve rigidity and viscosity, and amorphous polyester can easily introduce a specific structure for controlling interfacial tension. Therefore, in order to achieve both suppression of toner breakage and crushing and suppression of charging member contamination, it is preferable to employ a toner configuration that makes effective use of the respective characteristics. In other words, it is more preferable that the amorphous polyester is unevenly distributed on the outside of the toner and a hard vinyl resin is present in the core portion from the viewpoint of easy suppression of toner breakage.

  Examples of the vinyl resin include the following.

Homopolymers of styrene such as polystyrene and polyvinyltoluene and substituted products thereof;
Styrene-propylene copolymer, styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer, styrene-butyl acrylate copolymer, Styrene-octyl acrylate copolymer, styrene-dimethylaminoethyl acrylate copolymer, styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate copolymer, styrene-methacrylic acid Dimethylaminoethyl acid copolymer, styrene-vinyl methyl ether copolymer, styrene-vinyl ethyl ether copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene -Maleic acid copolymerization , Styrene - styrene copolymer and maleic acid ester copolymers;
Polymethyl methacrylate, polybutyl methacrylate, polyvinyl acetate, polyethylene, polypropylene, polyvinyl butyral, polyacrylic acid resin, and the like can be used. These can be used alone or in combination of two or more. Among these, styrene copolymers, and styrene-butyl acrylate copolymers are particularly preferable from the viewpoints of development characteristics and ease of control of fixability.

  The amorphous polyester having an amorphous polyester together with the binder resin and dissolved in styrene / butyl acrylate = 80/20 (mass ratio) has an interfacial tension in a tricalcium phosphate aqueous solution of pH 6.0 of 25 mN / m or more and 38 mN / m or less is preferable from the viewpoint of controlling an extremely fine uneven shape on the surface of the toner base particles.

  As described above, considering the generation of toner mother particles in the suspension polymerization method, for example, the polymerizable monomer composition repeats coalescence, shearing, and coalescence in the granulation step. Among these two phenomena, when shearing is likely to occur compared to unity, fine particles are likely to be generated, and the polymerizable monomer composition is stably present as oil droplets in the aqueous medium. The dispersant is deprived of the fine particles. As a result, there are not enough dispersants to stabilize the oil droplets of the toner particle size, and uneven toner base particles are formed. The reason is not clear, but the interfacial tension of the amorphous polyester dissolved in styrene / butyl acrylate = 80/20 (mass ratio) in an aqueous solution of tricalcium phosphate at pH 6.0 is 25 mN / m or more and 38 mN / m. If it is below, the balance between the shearing and coalescence of the oil droplets formed by the polymerizable monomer composition in the granulation step is slightly shifted to the shearing side. Thus, it is considered that extremely fine irregularities can be formed while suppressing the generation of fine particles as much as possible. Since amorphous polyester can easily introduce a specific site in a molecular chain, it is preferable to change the molecular chain structure in the amorphous polyester chain as a method for controlling the interfacial tension.

  The content of the amorphous polyester is preferably 5.0 parts by mass or more and 30.0 parts by mass or less with respect to 100 parts by mass of the binder resin. More preferably, it is 5.0 to 25.0 parts by mass. When the content is 5.0 parts by mass or more, it becomes easy to control the uneven shape on the surface of the toner base particles, and it becomes easy to suppress contamination of the charging member due to an external additive or the like. On the other hand, when the amount is 30.0 parts by mass or less, the generation of irregularly shaped particles is easily suppressed, the toner is easily prevented from being broken or crushed, and the fog is likely to be improved.

  Furthermore, from the viewpoint of ease of suppression of charging member contamination by controlling the extremely fine uneven shape on the surface of the toner base particles, the amorphous polyester is composed of a monomer unit derived from an alcohol component and a straight chain having 6 to 12 carbon atoms. A monomer unit derived from a chain aliphatic dicarboxylic acid and derived from a linear aliphatic dicarboxylic acid having 6 to 12 carbon atoms with respect to all monomer units derived from a carboxylic acid component in the amorphous polyester. It is preferable to contain 10 mol% or more and 70 mol% or less of monomer units.

  As described above, as a preferable means for imparting the surface irregularity shape, one is to change the molecular chain structure in the amorphous polyester chain, so that the polymerizable monomer composition in the aqueous medium can be changed. A method of controlling the interfacial tension is preferred. As a result of studies by the present inventors, a molecular chain structure preferable for introduction from the viewpoint of easy control of the interfacial tension is, for example, a site derived from a linear aliphatic dicarboxylic acid having 6 to 12 carbon atoms. By carrying out like this, the interfacial tension with respect to water can be reduced compared with before introduction.

  Moreover, it turned out that electrostatic offset improves remarkably as an unexpected effect by having C6-C12 linear aliphatic dicarboxylic acid.

  The electrostatic offset is a phenomenon that occurs when toner on the paper, which is not sufficiently melted near the fixing nip, electrostatically flies to the fixing film side, not thermally at the time of fixing. As a result, when the fixing film rotates once, the toner flying to the fixing film side is fixed again on the paper, resulting in an image defect. If this electrostatic offset does not occur, the fixing bias mechanism becomes unnecessary and can greatly contribute to the miniaturization of the main body.

  There are two possible strategies for improving electrostatic offset. One is to make the toner charge distribution uniform, and the other is to release the charge stored in the toner layer transferred onto the paper. This electrostatic offset is a phenomenon that easily occurs in a low-temperature and low-humidity environment where the toner is likely to be charged up and the charge distribution is likely to be broad.

  When an amorphous polyester having a straight chain aliphatic dicarboxylic acid having 6 to 12 carbon atoms is contained in the toner base particles, the straight chain aliphatic dicarboxylic acid site is folded nicely. As a result, it is considered that the amorphous polyester is likely to have a structure like a pseudo crystalline state, and the charge of the toner layer after being transferred onto the paper can be effectively released. Therefore, even in a situation where the toner is likely to be charged up in the second half of the durability, the electrostatic offset resistance is likely to be improved.

  If the straight aliphatic dicarboxylic acid has 6 or more carbon atoms, the straight aliphatic dicarboxylic acid moiety is easily folded, so that it becomes easy to have a structure like a quasicrystalline state, and the charge can be easily released. As a result, the electrostatic offset resistance is improved. On the other hand, when the number of carbon atoms of the linear aliphatic dicarboxylic acid is 12 or less, the interfacial tension with respect to water can be easily controlled, so that it is easy to control the extremely fine uneven shape on the surface of the toner base particles.

  When the content of the monomer unit derived from the linear aliphatic dicarboxylic acid is 10 mol% or more, a large number of charge leak points can be earned, and the electrostatic offset resistance is easily improved. In addition, when the content of the monomer unit derived from the linear aliphatic dicarboxylic acid is 70 mol% or less, it is easy to control the interfacial tension with respect to water, and it is easy to suppress cracking and crushing of the toner. The content of the unit derived from the linear aliphatic dicarboxylic acid is more preferably 20 mol% or more and 50 mol% or less. The “monomer unit” refers to a reacted form of a monomer substance in a polymer.

  Examples of the carboxylic acid component for obtaining the amorphous polyester include linear aliphatic dicarboxylic acids having 6 to 12 carbon atoms and other carboxylic acids. Examples of the linear aliphatic dicarboxylic acid having 6 to 12 carbon atoms include adipic acid, suberic acid, sebacic acid, and 1,12-dodecanedioic acid. Examples of the carboxylic acid other than the straight chain aliphatic dicarboxylic acid having 6 to 12 carbon atoms include the following.

  Examples of the divalent carboxylic acid component include maleic acid, fumaric acid, phthalic acid, isophthalic acid, terephthalic acid, succinic acid, glutaric acid, n-dodecenyl succinic acid, anhydrides of these acids, and lower alkyl esters. It is done.

  Examples of the trivalent or higher polyvalent carboxylic acid component include 1,2,4-benzenetricarboxylic acid, 2,5,7-naphthalenetricarboxylic acid, pyromellitic acid, emporic trimer acid and acid anhydrides thereof, lower Examples include alkyl esters. Among these, terephthalic acid is preferably used because it can maintain a high peak molecular weight and easily maintain durability.

  In addition to the propylene oxide adduct of bisphenol A, the following are mentioned as an alcohol component for obtaining amorphous polyester. Examples of the divalent alcohol component include an ethylene oxide adduct of bisphenol A, ethylene glycol, 1,3-propylene glycol, neopentyl glycol, and the like. Examples of the trivalent or higher alcohol component include sorbitol, pentaerythritol, dipentaerythritol, and the like.

  The dihydric alcohol component and the trihydric or higher polyhydric alcohol component can be used alone or in combination of a plurality of compounds. Among these, as the alcohol component, an alcohol component derived from bisphenol A is preferably used.

  The amorphous polyester can be produced by an esterification reaction or a transesterification reaction using the above alcohol component and carboxylic acid component. In the case of polycondensation, a known esterification catalyst such as dibutyltin oxide may be appropriately used to promote the reaction.

  The molar ratio of the alcohol component and the carboxylic acid component (carboxylic acid component / alcohol component), which is the raw material monomer of the amorphous polyester, is preferably 0.60 or more and 1.00 or less.

  The glass transition temperature (Tg) of the amorphous polyester is preferably 45 ° C. or higher and 75 ° C. or lower from the viewpoint of fixability and heat resistant storage stability. The glass transition temperature (Tg) can be measured with a differential scanning calorimeter (DSC).

  The peak molecular weight (Mp (P)) of the amorphous polyester is preferably from 8000 to 13000, and the softening point is preferably from 85 ° C. to 105 ° C.

  When the peak molecular weight (Mp (P)) is 8000 or more, it becomes easy to suppress the cracking and crushing of the toner during long-term use. Further, when the peak molecular weight (Mp (P)) is 13000 or less, melting by heat occurs instantaneously, so that the toner layer can be sufficiently adhered on the paper.

  Further, if the softening point of the amorphous polyester is 85 ° C. or higher, it becomes easy to suppress the breakage and crushing of the toner through durability. Further, when the softening point is 105 ° C. or lower, melting by heat occurs instantaneously, so that the toner layer can be sufficiently adhered on the paper.

  In order to control the peak molecular weight and softening point of the amorphous polyester within the above range, it is preferable to contain a unit derived from a linear aliphatic dicarboxylic acid having 6 to 12 carbon atoms within the above range.

  Further, it is preferable that a matrix-domain structure is observed in the cross section of the toner observed with a transmission electron microscope (TEM), the vinyl resin forms a matrix, and the amorphous polyester forms a domain. Further, the domain may exist in an area of 96% by area or more based on the total area of the amorphous polyester domain within 75% of the distance between the outline and the center point of the cross section from the outline of the cross section. preferable.

  The area ratio (hereinafter also referred to as “75% area ratio”) of the amorphous polyester domain existing within 75% of the distance between the outline and the center point of the cross section from the outline of the toner cross section is 96 area% or more. In this case, since the amorphous polyester is unevenly distributed as a whole, electric charges can be easily released from the toner layer of the post-transfer image, so that the electrostatic offset is easily improved. More preferably, it is 98 area% or more.

  Next, it is preferable that the number average particle diameter of the amorphous polyester domain is 0.3 μm or more and 3.0 μm or less. More preferably, it is 0.3 μm or more and 2.0 μm or less. When the number average particle size of the domains is 0.3 μm or more and 3.0 μm or less, it is possible to control the presence state of the domains in the toner base particles and to reduce the domain variation between the toner base particles.

  As a measure to form amorphous polyester domains near the surface of the toner base particles and control the number average diameter of the amorphous polyester domains, adjustment of the acid value and hydroxyl value of the amorphous polyester, amorphous property Giving lipophilic sites to the molecular chain ends of the polyester, adjusting the softening point of the amorphous polyester and the toner, and adjusting the production conditions of the toner base particles, such as the cooling step after the completion of polymerization, the holding time after cooling, etc. Is mentioned.

  In this way, in order to control the number average particle diameter of the domain in which the amorphous polyester forms domains near the surface of the toner base particles, for example, in the case of suspension polymerization, the acid value of the amorphous polyester and It can be controlled by the hydroxyl value. Further, it can be adjusted by imparting a lipophilic portion to be described later to the molecular chain terminal of the amorphous polyester, controlling the softening point of the amorphous polyester and the toner, or controlling the annealing conditions during toner production.

  As a method for controlling the surface irregularity shape of the toner base particles, for example, a control by suspension polymerization method is used in the production method, and a method of controlling the acid value or hydroxyl value of the amorphous polyester is used in the toner material.

It is preferable that the acid value Av (mgKOH / g) and the hydroxyl value OHv (mgKOH / g) of the amorphous polyester satisfy the following formulas (3) and (4).
1.0 ≦ Av ≦ 4.0 (3)
2.0 ≦ Av + 0.1OHv ≦ 8.0 (4)

  Within the above range, it becomes easy to control the white area ratio, and as a result, it is easy to reduce irregularly shaped particles.

  Next, the hydroxyl value OHv of the amorphous polyester is preferably 40.0 mgKOH / g or less. For example, when the toner is obtained by suspension polymerization, it is preferable that the hydroxyl value OHv of the amorphous polyester is 40.0 mgKOH / g or less because the amorphous polyester easily forms a plurality of domains in the vicinity of the toner surface. .

  In order to control the acid value Av of the amorphous polyester to 1.0 mgKOH / g or more and 4.0 mgKOH / g or less and the hydroxyl value OHv to 40.0 mgKOH / g or less, the molecular chain terminal of the amorphous polyester is It is preferable to have a lipophilic site.

  Since the molecular chain terminal of the amorphous polyester has a lipophilic part, it is easy to interact with the vinyl resin, and thus the domain size can be easily controlled.

  In order to have a lipophilic part at the molecular chain terminal, it is preferable to react a compound having a lipophilic part at the molecular chain terminal of the amorphous polyester.

  The compound having a lipophilic moiety is preferably an aliphatic monoalcohol having 10 to 50 carbon atoms and / or an aliphatic monocarboxylic acid having 11 to 51 carbon atoms. These compounds include dodecanoic acid (lauric acid), tetradecanoic acid (myristic acid), hexadecanoic acid (palmitic acid), octadecanoic acid (stearic acid), eicosanoic acid (arachidic acid), docosanoic acid (behenic acid), tetracosanoic acid (Lignoceric acid), caprin alcohol, lauryl alcohol, mystyryl alcohol, cetanol, stearyl alcohol, arachidyl alcohol, behenyl alcohol, lignoceryl alcohol and the like.

  The number average particle diameter (D1) of the toner of the present invention is preferably 5.0 μm or more and 9.0 μm or less. If the number average particle diameter (D1) is in the above range, good fluidity can be obtained, and fogging tends to be improved because it is easily triboelectrically charged at the regulating portion.

If necessary, the toner base particles may contain a charge control agent to improve charging characteristics. Various types of charge control agents can be used, and charge control agents that can quickly maintain a constant charge amount with a high charging speed are particularly preferable. Further, when the toner is produced using a polymerization method as described later, a charge control agent having a low polymerization inhibitory property and substantially free from a solubilized product in an aqueous dispersion medium is particularly preferable. As a charge control agent,
Metal compounds of aromatic carboxylic acids such as salicylic acid, alkylsalicylic acid, dialkylsalicylic acid, naphthoic acid, dicarboxylic acid;
Metal salts or metal complexes of azo dyes or azo pigments;
A polymer compound having a sulfonic acid or carboxylic acid group in the side chain;
Boron compounds;
Urea compounds;
Silicon compounds;
Examples include calix arene.

  The amount of these charge control agents used is preferably 0.1 parts by mass or more and 10.0 parts by mass or less, more preferably 0.1 parts by mass or less with respect to 100 parts by mass of the binder resin when added inside the toner base particles. 1 part by mass or more and 5.0 parts by mass or less. Further, when added outside the toner base particles, it is preferably 0.005 parts by mass or more and 1.000 parts by mass or less, more preferably 0.010 parts by mass or more and 0.300 parts by mass with respect to 100 parts by mass of the toner base particles. Or less.

  The toner base particles may contain a release agent in order to improve fixability. The content of the release agent in the toner base particles is preferably 1.0 part by mass or more and 30.0 parts by mass or less, and 3.0 parts by mass or more and 25.0 parts by mass with respect to 100 parts by mass of the binder resin. It is more preferable that the amount is not more than parts.

  If the content of the release agent is 1.0 part by mass or more, it becomes easy to control the state of presence of the release agent as described above, and it becomes easier to further suppress white spots. Moreover, if it is 30.0 mass parts or less, it will become easy to suppress the toner deterioration at the time of long-term use.

As a mold release agent,
Petroleum waxes such as paraffin wax, microcrystalline wax, petrolatum and derivatives thereof;
Montan wax and its derivatives;
Hydrocarbon wax and its derivatives by Fischer-Tropsch process;
Polyolefin waxes such as polyethylene and derivatives thereof;
Examples thereof include natural waxes such as carnauba wax and candelilla wax, and derivatives thereof. Derivatives include oxides, block copolymers with vinyl monomers, and graft modified products. In addition, fatty acids such as higher aliphatic alcohols, stearic acid and palmitic acid, acid amide waxes, ester waxes, hardened castor oil and derivatives thereof, plant waxes, animal waxes and the like can also be used as mold release agents.

  Among these release agents, paraffin wax is preferably used from the viewpoint of easily suppressing toner breakage and crushing.

  Further, the melting point defined by the maximum endothermic peak temperature at the time of temperature rise measured by a differential scanning calorimeter (DSC) of these release agents is preferably 60 ° C. or more and 140 ° C. or less, and 65 ° C. or more and 120 ° C. It is more preferable that it is below ℃. When the melting point is 60 ° C. or higher, it is easy to suppress toner deterioration during long-term use. When the melting point is 140 ° C. or lower, the low-temperature fixability is hardly lowered.

  The melting point of the release agent is the peak top of the endothermic peak when measured by DSC. Moreover, the measurement of the peak top of the endothermic peak is performed according to ASTM D 3417-99. For these measurements, for example, DSC-7 manufactured by PerkinElmer, DSC2920 manufactured by TA Instruments, and Q1000 manufactured by TA Instruments can be used. The temperature correction of the device detection unit uses the melting points of indium and zinc, and the correction of heat uses the heat of fusion of indium. As a measurement sample, an aluminum pan is used, and an empty pan is set as a control and measured.

  Next, the colorant will be described.

  As the black colorant, carbon black, magnetic fine particles, and those which are toned in black using the following yellow / magenta / cyan colorants are used.

  Another effective means for reducing the size of the printer is a one-component development system. It is also an effective means to eliminate the supply roller that supplies the toner in the cartridge to the toner carrier.

  As such a one-component developing method in which the supply roller is omitted, a magnetic one-component developing method is preferable, and a magnetic toner using a magnetic material is preferable as a toner colorant. By using such a magnetic toner, it is possible to have high transportability and colorability.

  Further, when the suspension polymerization method is applied as a toner production method, it is preferable to use a magnetic fine particle that has been subjected to a hydrophobic treatment, and the degree of hydrophobicity is preferably 60.0% or more and 80.0% or less. . Within the above range, magnetic fine particles are oriented in the vicinity of the surface of the toner base particles, and are resistant to external stress, and at the same time, a more precise uneven shape is imparted to the surface while having a low white area ratio. Thus, the charging member contamination suppressing effect can be further improved.

The magnetic fine particles are preferably composed mainly of magnetic iron oxide such as triiron tetroxide and γ-iron oxide, and may contain elements such as phosphorus, cobalt, nickel, copper, magnesium, manganese, aluminum and silicon. These magnetic fine particles preferably have a BET specific surface area of 2 m ² / g or more and 30 m ² / g or less, more preferably 3 m ² / g or more and 28 m ² / g or less by a nitrogen adsorption method. Further, those having a Mohs hardness of 5 to 7 are preferred. The shape of the magnetic fine particle includes polyhedron, octahedron, hexahedron, spherical shape, needle shape, scale shape, and the like, but those having low anisotropy such as polyhedron, octahedron, hexahedron, and spherical shape increase the image density. Preferred above.

  The magnetic fine particles preferably have a number average particle diameter of 0.10 μm to 0.40 μm. When the number average particle diameter is 0.10 μm or more, the magnetic fine particles are difficult to aggregate, and the uniform dispersibility of the magnetic fine particles in the toner is improved. A number average particle size of 0.40 μm or less is preferably used because the coloring power of the toner is improved.

  The number average particle diameter of the magnetic fine particles can be measured using a transmission electron microscope. Specifically, after sufficiently dispersing toner base particles to be observed in the epoxy resin, a cured product obtained by curing in an atmosphere at a temperature of 40 ° C. for 2 days is obtained. The obtained cured product is used as a flaky sample by a microtome, and the diameter of 100 magnetic fine particles in the field of view is measured with a transmission electron microscope (TEM) with a photograph with an enlargement magnification of 10,000 to 40,000 times. Then, the number average particle diameter is calculated based on the equivalent diameter of a circle equal to the projected area of the magnetic fine particles. It is also possible to measure the particle size with an image analyzer.

  The magnetic fine particles used in the toner of the present invention can be produced, for example, by the following method. An aqueous solution containing ferrous hydroxide is prepared by adding an alkali such as sodium hydroxide in an amount equivalent to or greater than the iron component to the ferrous salt aqueous solution. Air was blown in while maintaining the pH of the prepared aqueous solution at pH 7 or higher, and ferrous hydroxide was oxidized while heating the aqueous solution to 70 ° C. or higher. First, seed crystals serving as the core of the magnetic iron oxide powder were formed. Generate.

  Next, an aqueous solution containing about 1 equivalent of ferrous sulfate is added to the slurry-like liquid containing seed crystals based on the amount of alkali added previously. While maintaining the pH of the solution at 5 to 10, the reaction of ferrous hydroxide proceeds while blowing air to grow a magnetic iron oxide powder with the seed crystal as a core. At this time, the shape and magnetic characteristics of the magnetic fine particles can be controlled by selecting an arbitrary pH, reaction temperature, and stirring conditions. As the oxidation reaction proceeds, the pH of the liquid shifts to the acidic side, but the pH of the liquid is preferably not less than 5. The magnetic fine particles can be obtained by filtering, washing, and drying the magnetic fine particles thus obtained by a conventional method.

  In addition, as described above, when the toner is produced by the suspension polymerization method in the present invention, it is very preferable that the surface of the magnetic fine particles is hydrophobized because the magnetic fine particles are easily included in the toner. When the surface treatment is performed by a dry method, the coupling agent treatment is performed on the washed, filtered and dried magnetic fine particles. When wet surface treatment is performed, after the oxidation reaction is completed, the dried product is redispersed, or after completion of the oxidation reaction, the iron oxide body obtained by washing and filtering is not dried but in another aqueous medium. The dispersion is redispersed and a coupling treatment is performed. Specifically, a silane coupling agent is added while stirring the redispersion sufficiently, and the temperature is increased after hydrolysis, or the coupling is performed by adjusting the pH of the dispersion to an alkaline region after hydrolysis. . Among these, from the viewpoint of performing a uniform surface treatment, it is preferable to carry out the surface treatment by reslurry as it is without drying after filtration and washing after completion of the oxidation reaction.

  In order to treat the surface of the magnetic fine particles with a wet method, that is, to treat the magnetic fine particles with a coupling agent in an aqueous medium, first, sufficiently disperse the magnetic fine particles in the aqueous medium so as to have a primary particle size so as not to settle or aggregate. Stir with a stirring blade. Next, an arbitrary amount of the coupling agent is added to the dispersion, and the surface treatment is performed while the coupling agent is hydrolyzed. At this time, the agglomeration is sufficiently carried out using a device such as a pin mill or a line mill while stirring. It is more preferable to perform the surface treatment while dispersing.

  Here, the aqueous medium is a medium containing water as a main component. Specific examples include water itself, water added with a small amount of surfactant, water added with a pH adjuster, and water added with an organic solvent. As the surfactant, nonionic surfactants such as polyvinyl alcohol are preferable. The surfactant is preferably added in an amount of 0.1 to 5.0 parts by mass with respect to 100 parts by mass of water. Examples of the pH adjuster include inorganic acids such as hydrochloric acid. Examples of the organic solvent include alcohols.

Examples of the coupling agent that can be used in the surface treatment of magnetic fine particles in the present invention include silane compounds, silane coupling agents, titanium coupling agents, and the like. More preferably used is a silane compound or a silane coupling agent, which is represented by the general formula (1).
R _m SiY _n general formula (1)
[Wherein, R represents an alkoxy group, m represents an integer of 1 to 3, Y represents a functional group such as an alkyl group, a phenyl group, a vinyl group, an epoxy group, or a (meth) acryl group, and n represents 1 To an integer of 3. However, m + n = 4. ]

  Examples of the silane compound or silane coupling agent represented by the general formula (1) include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris (β-methoxyethoxy) silane, β- (3,4-epoxycyclohexyl) ethyltri Methoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, γ-aminopropyltriethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, γ-methacryloxypropyltri Methoxysilane, vinyltriacetoxysilane, methyltrimethoxysilane, dimethyldimethoxysilane, phenyltrimethoxysilane, diphenyldimethoxysilane, methyltriethoxysilane, dimethyldiethoxysilane, phenyltriethoxy Lan, diphenyldiethoxysilane, n-butyltrimethoxysilane, isobutyltrimethoxysilane, trimethylmethoxysilane, n-hexyltrimethoxysilane, n-octyltrimethoxysilane, n-octyltriethoxysilane, n-decyltrimethoxysilane , Hydroxypropyltrimethoxysilane, n-hexadecyltrimethoxysilane, n-octadecyltrimethoxysilane and the like.

Among these, from the viewpoint of imparting high hydrophobicity to the magnetic fine particles, it is preferable to use an alkyltrialkoxysilane represented by the following general formula (2).
_{C p H 2p + 1 -Si- (} OC q H 2q + 1) 3 (2)
[Wherein, p represents an integer of 2 to 20 (more preferably 3 to 15), and q represents an integer of 1 to 3 (more preferably 1 or 2). ]

  When p in the above formula is 2 or more, it becomes easy to sufficiently impart hydrophobicity to the magnetic fine particles. Moreover, when p is 20 or less, in addition to sufficient hydrophobicity, coalescence of magnetic fine particles can be suppressed. Furthermore, when q is 3 or less, the reactivity of the silane coupling agent is good and the hydrophobicity is sufficient.

  When using the said silane coupling agent, it is possible to process independently or to process in combination of several types. When using several types together, you may process separately with each coupling agent, and may process simultaneously.

  In the present invention, other colorants may be used in addition to the magnetic fine particles. Examples of the colorant that can be used in combination include magnetic or nonmagnetic inorganic compounds in addition to the above-described known dyes and pigments. Specifically, ferromagnetic metal particles such as cobalt and nickel, or alloys obtained by adding chromium, manganese, copper, zinc, aluminum, rare earth elements and the like to these. Examples thereof include particles such as hematite, titanium black, nigrosine dye / pigment, carbon black, and phthalocyanine. These are also preferably used by treating the surface.

  The amount contained in the toner base particles is preferably 20 parts by mass or more and 200 parts by mass or less, more preferably 40 parts by mass or more, with respect to 100 parts by mass of the polymerizable monomer or binder resin that forms the binder resin. It is 150 parts by mass or less.

  Examples of the yellow colorant include compounds typified by condensed azo compounds, isoindolinone compounds, anthraquinone compounds, azo metal complexes, methine compounds, and allylamide compounds. Specifically, the following C.I. I. Pigment Yellow 12, 13, 14, 15, 17, 62, 73, 74, 83, 93, 94, 95, 97, 109, 110, 111, 120, 128, 129, 138, 147, 150, 151, 154, 155, 168, 180, 185, 214.

  Examples of the magenta colorant include condensed azo compounds, diketopyrrolopyrrole compounds, anthraquinone compounds, quinacridone compounds, basic dye lake compounds, naphthol compounds, benzimidazolone compounds, thioindigo compounds, and perylene compounds. Specifically, the following C.I. I. Pigment Red 2, 3, 5, 6, 7, 23, 48: 2, 48: 3, 48: 4, 57: 1, 81: 1, 122, 146, 166, 169, 177, 184, 185, 202, 206, 220, 221, 238, 254, 269, C.I. I. And CI Pigment Bio Red 19.

  Examples of cyan colorants include copper phthalocyanine compounds and derivatives thereof, anthraquinone compounds, and basic dye lake compounds. Specifically, C.I. I. Pigment blue 1, 7, 15, 15: 1, 15: 2, 15: 3, 15: 4, 60, 62, 66.

  These colorants can be used alone or in combination and further in the form of a solid solution. The colorant is selected from the viewpoints of hue angle, saturation, brightness, light resistance, OHP transparency, and dispersibility in the toner. The addition amount of the colorant is preferably 1 part by mass or more and 20 parts by mass or less with respect to 100 parts by mass of the polymerizable monomer or binder resin that generates the binder resin.

  When the toner base particles are produced by a pulverization method, for example, a toner component such as a binder resin and a colorant and, if necessary, a release agent and other additives are sufficiently mixed by a mixer such as a Henschel mixer or a ball mill. To do. Then, melt and knead using a heat kneader such as a heating roll, kneader, extruder, etc., disperse or dissolve the above materials, cool and solidify, pulverize, classify, and perform surface treatment as necessary Thus, toner mother particles can be obtained. Either the classification or the surface treatment may be performed first. In the classification step, it is preferable to use a multi-division classifier from the viewpoint of production efficiency.

  Control of the dispersion state of the amorphous polyester by the pulverization method can be achieved by a treatment such as external addition of the amorphous polyester. Therefore, in the present invention, it is preferable to produce toner mother particles in an aqueous medium such as a dispersion polymerization method, an association aggregation method, a dissolution suspension method, a suspension polymerization method, etc. Among them, the suspension polymerization method is more preferable. . By adopting these production methods, it becomes easier to achieve the above-described unevenness control on the surface of the toner base particles.

  The suspension polymerization method is a polymerizable monomer that forms a binder resin, an amorphous polyester, and a colorant (and, if necessary, a release agent, a polymerization initiator, a crosslinking agent, a charge control agent, Other additives) are dissolved or dispersed to obtain a polymerizable monomer composition. Thereafter, this polymerizable monomer composition is added to a continuous phase (for example, an aqueous medium (which may contain a dispersion stabilizer if necessary)). Then, particles of the polymerizable monomer composition are formed in the continuous phase (in the aqueous medium), and the polymerizable monomer contained in the particles is polymerized. In this way, the toner is obtained. The toner obtained by the suspension polymerization method (hereinafter also referred to as “polymerized toner”) has a substantially spherical shape of the individual toner base particles. Since it becomes easy to charge, it is easy to suppress fogging and to improve the image quality.

  The following are mentioned as a polymerizable monomer used for manufacture of a polymerization toner.

As a polymerizable monomer,
Styrene monomers such as styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, p-methoxystyrene, p-ethylstyrene;
Methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, n-propyl acrylate, n-octyl acrylate, dodecyl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, 2-chloroethyl acrylate, Acrylic esters such as phenyl acrylate;
Methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-octyl methacrylate, dodecyl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate, phenyl methacrylate, methacrylic acid Methacrylic acid esters such as dimethylaminoethyl and diethylaminoethyl methacrylate;
Etc. Other examples include acrylonitrile, methacrylonitrile, and acrylamide. These can be used alone or in combination of two or more.

  Among the polymerizable monomers described above, styrene or a styrene derivative is preferably used alone or in combination of a plurality of types from the viewpoint of the development characteristics and durability of the toner.

  The polymerizable monomer composition preferably contains a polar resin. In the suspension polymerization method, the toner base particles are produced in an aqueous medium. Therefore, by adding a polar resin, the surface of the toner base particles can have a polar resin, and the chargeability is easily improved. Easy to suppress fog.

As the polar resin, for example,
Homopolymers of styrene such as polystyrene and polyvinyltoluene and substituted products thereof;
Styrene-propylene copolymer, styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer, styrene-butyl acrylate copolymer, Styrene-octyl acrylate copolymer, styrene-dimethylaminoethyl acrylate copolymer, styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate copolymer, Styrene-dimethylaminoethyl methacrylate copolymer, styrene-vinyl methyl ether copolymer, styrene-vinyl ethyl ether copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer Coalescence, styrene-maleic acid Polymer, a styrene - styrene copolymer and maleic acid ester copolymers;
Examples thereof include polymethyl methacrylate, polybutyl methacrylate, polyvinyl acetate, polyethylene, polypropylene, polyvinyl butyral, silicone resin, polyamide resin, epoxy resin, polyacrylic acid resin, terpene resin, and phenol resin. These can be used alone or in combination of two or more. Moreover, you may introduce | transduce functional groups, such as an amino group, a carboxy group, a hydroxyl group, a sulfonic acid group, a glycidyl group, a nitrile group, in these polymers.

  As the polymerization initiator used in the production of the toner by the polymerization method, those having a half-life at the time of the polymerization reaction of 0.5 hours or more and 30.0 hours or less are preferable. In addition, when the polymerization reaction is performed using an addition amount of 0.5 parts by mass or more and 20.0 parts by mass or less with respect to 100 parts by mass of the polymerizable monomer, the toner can have desirable strength and appropriate melting characteristics. it can.

  Specific examples of the polymerization initiator include 2,2′-azobis- (2,4-dimethylvaleronitrile), 2,2′-azobisisobutyronitrile, 1,1′-azobis (cyclohexane-1 -Carbonitrile), 2,2′-azobis-4-methoxy-2,4-dimethylvaleronitrile, azo or diazo polymerization initiators such as azobisisobutyronitrile, benzoyl peroxide, methyl ethyl ketone peroxide, diisopropyl Peroxide-based polymerization initiators such as peroxycarbonate, cumene hydroperoxide, 2,4-dichlorobenzoyl peroxide, lauroyl peroxide, t-butylperoxy 2-ethylhexanoate, t-butylperoxypivalate Is mentioned.

  When the toner base particles are produced by a polymerization method, a crosslinking agent may be added. A preferable addition amount is 0.01 parts by mass or more and 5.00 parts by mass or less with respect to 100 parts by mass of the polymerizable monomer. It is.

Here, as the crosslinking agent, compounds having two or more polymerizable double bonds are mainly used.
Aromatic divinyl compounds such as divinylbenzene and divinylnaphthalene;
Carboxylic acid esters having two double bonds such as ethylene glycol diacrylate, ethylene glycol dimethacrylate, 1,3-butanediol dimethacrylate, etc .;
Divinyl compounds such as divinylaniline, divinyl ether, divinyl sulfide, divinyl sulfone;
A compound having three or more vinyl groups is used alone or as a mixture of two or more.

  When the toner base particles are produced by a polymerization method, preferably, the above-described toner composition or the like is added and uniformly dissolved or dispersed by a disperser to obtain a polymerizable monomer composition. Examples of the disperser include a homogenizer, a ball mill, and an ultrasonic disperser. The obtained polymerizable monomer composition is suspended in an aqueous medium containing a dispersion stabilizer. At this time, the particle size of the toner base particles obtained becomes sharper by using a high-speed disperser such as a high-speed stirrer or an ultrasonic disperser to obtain a desired toner size all at once. The polymerization initiator may be added at the same time when other additives are added to the polymerizable monomer, or may be mixed immediately before being suspended in the aqueous medium. Moreover, a polymerization initiator can also be added immediately after granulation and before starting a polymerization reaction.

  After granulation, stirring may be carried out using an ordinary stirrer to such an extent that the particle state is maintained and particle floating and sedimentation are prevented.

  In the case of producing a toner, various surfactants, organic dispersants, and inorganic dispersants can be used as a dispersion stabilizer. Among these, inorganic dispersants can be preferably used because they do not easily generate harmful ultrafine powders and have obtained dispersion stability due to their steric hindrance. Examples of such inorganic dispersants include tricalcium phosphate, magnesium phosphate, aluminum phosphate, zinc phosphate, hydroxyapatite and other phosphate polyvalent metal salts, calcium carbonate, magnesium carbonate and other carbonates, calcium metasilicate, calcium sulfate, sulfuric acid Inorganic salts such as barium, and inorganic compounds such as calcium hydroxide, magnesium hydroxide, and aluminum hydroxide can be used.

  These inorganic dispersants are desirably used in an amount of 0.2 parts by mass or more and 20.0 parts by mass or less with respect to 100 parts by mass of the polymerizable monomer. Moreover, the said dispersion stabilizer may be used independently and may use multiple types together. Further, a surfactant may be used in combination.

  In the step of polymerizing the polymerizable monomer, the polymerization temperature is usually 40 ° C. or higher, preferably 50 ° C. or higher and 90 ° C. or lower. When the polymerization is carried out in this temperature range, the release agent to be sealed inside precipitates by phase separation, and the encapsulation becomes more complete.

  In order to obtain a toner having an amorphous polyester domain by suspension polymerization, the following steps are preferably performed.

  After the polymerization of the polymerizable monomer is completed to obtain colored particles, the colored particles are dispersed in an aqueous medium, and the vicinity of the softening point of the amorphous polyester (for example, the softening point of the amorphous polyester + 10 ° C. Specifically, the temperature is raised to about 100 ° C., and the temperature is preferably maintained for 30 minutes or more. The upper limit is not particularly limited, but is preferably maintained for 24 hours or less from the viewpoint of production tact.

  Further, it is preferable to perform the following operation in the subsequent cooling step. Specifically, the aqueous medium is preferably cooled at a cooling rate of 5.0 ° C./min or higher, more preferably at a cooling rate of 20 ° C./min or lower, to a glass transition temperature (Tg) or lower of the toner. It is more preferable to cool at a rate of 100 ° C./min or more. The upper limit of the cooling rate is about 500 ° C./min or less from the viewpoint of production tact.

  Moreover, after cooling at the cooling rate, it is preferable to hold at that temperature for 30 minutes or more. The holding time is more preferably 60 minutes or more, and further preferably 120 minutes or more. The upper limit of the holding time is not particularly limited, but is about 24 hours or less from the viewpoint of production tact.

  The obtained polymer particles are filtered, washed and dried to obtain toner base particles.

  The toner base particles can be used as the toner as they are, but the toner base particles can be added with inorganic fine particles as will be described later, and the toner can be obtained by adhering inorganic fine particles to the surface of the toner base particles. It is also possible to insert a classification step in the manufacturing process (before mixing the inorganic fine particles) to cut coarse powder and fine powder contained in the particles.

  Further, in the toner, it is preferable that inorganic fine particles having a primary particle number average diameter of 4 nm to 80 nm, more preferably 6 nm to 40 nm, are added (externally added) to the toner base particles as a fluidizing agent. . Furthermore, it is more preferable to use together inorganic fine particles having a primary particle number average diameter of 80 nm to 200 nm. In this way, the fluidity of the toner can be ensured through durability, uniform and stable frictional charging performance can be obtained, and fog and electrostatic offset are easily improved. Inorganic fine particles are added to improve the fluidity of the toner and make the charge of the toner uniform. However, the inorganic fine particles have functions such as adjusting the charge amount of the toner and improving the environmental stability by hydrophobizing the inorganic fine particles. Giving is also a preferred form.

  In the present invention, the number average diameter of the primary particles of the inorganic fine particles is measured by using a photograph of the toner magnified by a scanning electron microscope.

  As the inorganic fine particles used in the present invention, fine particles such as silica, titanium oxide, and alumina can be used. Examples of the silica fine particles include so-called dry silica produced by vapor phase oxidation of silicon halides or dry silica called fumed silica, and so-called wet silica produced from water glass.

However, dry silica having fewer silanol groups on the surface and inside of the silica and less production residue such as Na ₂ O and SO ₃ ^2- is preferred. In dry silica, it is also possible to obtain fine particles of silica and other metal oxides by using other metal halogen compounds such as aluminum chloride and titanium chloride together with silicon halogen compounds in the production process. , Including them.

  The addition amount of the inorganic fine particles is preferably 0.1 parts by mass or more and 3.0 parts by mass or less with respect to 100 parts by mass of the toner base particles. The content of inorganic fine particles can be quantified using a calibration curve prepared from a standard sample using fluorescent X-ray analysis.

  In the present invention, it is preferable that the inorganic fine particles have been subjected to a hydrophobic treatment since the environmental stability of the toner can be improved. Examples of the treatment agent used for the hydrophobic treatment of the inorganic fine particles include silicone varnish, various modified silicone varnishes, silicone oil, various modified silicone oils, silane compounds, and silane coupling agents. In addition, treatment agents such as other organosilicon compounds and organotitanium compounds are listed. These can be used alone or in combination of two or more.

  Among the above-mentioned treatment agents, those treated with silicone oil are preferred, and those treated with silicone oil are more preferred simultaneously with or after the hydrophobic treatment of inorganic fine particles with a silane compound. As a method for treating such inorganic fine particles, for example, as a first stage reaction, a silylation reaction is performed with a silane compound, silanol groups are eliminated by chemical bonds, and then a second stage reaction is performed on the surface with silicone oil. A hydrophobic thin film can be formed.

The silicone oil is preferably a viscosity at 25 ° C. is 10 mm ² / s or more 200,000 mm ² / s or less things, more preferably the following 3,000 mm ² / s or more 80,000mm ² / s.

  As the silicone oil used, for example, dimethyl silicone oil, methylphenyl silicone oil, α-methylstyrene modified silicone oil, chlorophenyl silicone oil, fluorine modified silicone oil and the like are particularly preferable.

  As a method of treating inorganic fine particles with silicone oil, for example, a method of directly mixing inorganic fine particles treated with a silane compound and silicone oil using a mixer such as a Henschel mixer, or spraying silicone oil onto inorganic fine particles A method is mentioned. Alternatively, after dissolving or dispersing silicone oil in an appropriate solvent, inorganic fine particles may be added and mixed to remove the solvent. A spraying method is more preferable in that the formation of aggregates of inorganic fine particles is relatively small.

  The treatment amount of the silicone oil is preferably 1 part by mass or more and 40 parts by mass or less, more preferably 3 parts by mass or more and 35 parts by mass or less with respect to 100 parts by mass of the inorganic fine particles. Within the range, good hydrophobicity is easily obtained.

The inorganic fine particles used in the present invention preferably have a specific surface area of 20 m ² / g or more and 350 m ² / g or less as measured by the BET method by nitrogen adsorption in order to impart good fluidity to the toner. ² / g or more 300 meters ² / g following are more preferable. The specific surface area is calculated using the BET multipoint method by adsorbing nitrogen gas on the sample surface using a specific surface area measuring device “Gemini 2375 Ver. 5.0” (manufactured by Shimadzu Corporation) according to the BET method. .

In the toner of the present invention, other additives such as, for example,
Lubricant particles such as fluororesin particles, zinc stearate particles, polyvinylidene fluoride particles;
Abrasives such as cerium oxide particles, silicon carbide particles, strontium titanate particles;
Fluidity-imparting agents such as titanium oxide particles and aluminum oxide particles;
Anti-caking agent;
A small amount of reverse polarity organic fine particles and inorganic fine particles can also be used as a developability improver. It is also possible to use the surface of these additives after hydrophobizing them.

  Next, a developing device to which the toner of the present invention can be officially applied will be described in detail with reference to the drawings.

  FIG. 1 is a schematic cross-sectional view illustrating an example of a developing device. FIG. 2 is a schematic cross-sectional view showing an example of an image forming apparatus in which a developing device is incorporated.

  In FIG. 1 or FIG. 2, an electrostatic latent image carrier 45, which is an image carrier on which an electrostatic latent image is formed, is rotated in the direction of arrow R1. The toner carrier 47 rotates in the direction of the arrow R2 to convey the toner 57 to the development area where the toner carrier 47 and the electrostatic latent image carrier 45 are opposed to each other. Further, a toner supply member 48 is in contact with the toner carrier, and the toner 57 is supplied to the surface of the toner carrier by rotating in the direction of arrow R3.

  Around the electrostatic latent image carrier 45, a charging roller 46, a transfer roller 50, a fixing device 51, a pickup roller 52, and the like are provided. The electrostatic latent image carrier 45 is charged by the charging roller 46. Then, exposure is performed by irradiating the electrostatic latent image carrier 45 with laser light by the laser generator 54, and an electrostatic latent image corresponding to the target image is formed. The electrostatic latent image on the electrostatic latent image carrier 45 is developed with toner in the developing device 49 to obtain a toner image. The toner image is transferred onto a transfer material (paper) 53 by a transfer member (transfer roller) 50 in contact with the electrostatic latent image carrier 45 via the transfer material. The transfer material (paper) 53 on which the toner image is placed is conveyed to the fixing device 51 and fixed on the transfer material (paper) 53.

  In the charging process in the developing device, the electrostatic latent image carrier and the charging roller are in contact with each other by forming a contact portion, and a predetermined charging bias is applied to the charging roller so that the surface of the electrostatic latent image carrier has a predetermined polarity and It is preferable to use a contact charging device that charges the potential. By performing contact charging in this manner, stable and uniform charging can be performed, and generation of ozone can be reduced. It is more preferable to use a charging roller that rotates in the same direction as the electrostatic latent image carrier in order to maintain uniform contact with the electrostatic latent image carrier and perform uniform charging.

  Next, it is preferable that the thickness of the toner layer on the toner carrier is regulated by the toner regulating member coming into contact with the toner carrier via the toner. By doing so, it is possible to obtain a high image quality without any defective regulation. As a toner regulating member that abuts on the toner carrier, a regulating blade is generally used and can be suitably used in the present invention.

  The developing step is preferably a step of applying a developing bias to the toner carrier and transferring the toner to the electrostatic latent image on the electrostatic latent image carrier to form a toner image. A voltage obtained by superimposing an alternating electric field on a DC voltage may be used.

  As the waveform of the alternating electric field, a sine wave, a rectangular wave, a triangular wave, or the like can be used as appropriate. Further, it may be a pulse wave formed by periodically turning on / off a DC power source. As described above, a bias whose voltage value periodically changes can be used as the waveform of the alternating electric field.

  In the present invention, when a method of conveying toner by magnetism without using a toner supply member is used, it is preferable to arrange a magnet inside the toner carrier (reference numeral 59 in FIG. 3). In this case, the toner carrier preferably has a fixed magnet having multiple poles inside, and preferably has 3 to 10 magnetic poles.

  Next, it describes regarding the measuring method of each physical property which concerns on this invention.

<Measurement method of white area ratio of toner base particles>
When observing the surface of a toner base particle with a scanning electron microscope (SEM) in a toner in which an external additive is externally added to the toner base particle, it is necessary to remove the external additive. For example, the following methods can be mentioned.

When the toner is a magnetic toner (1) 45 mg of magnetic toner is put in a sample bottle, and 10 mL of methanol is added.
(2) Disperse the sample for 1 minute with an ultrasonic cleaner to separate the external additive.
(3) The magnetic toner base particles and the external additive are separated by suction filtration (10 μm membrane filter). Alternatively, only the supernatant liquid may be separated by applying a magnet to the bottom of the sample bottle to fix the magnetic toner mother particles.
(4) The above (2) and (3) are carried out three times in total, and the obtained magnetic toner mother particles are sufficiently dried in a vacuum dryer at room temperature. After observing the magnetic toner mother particles from which the external additive has been removed with a scanning electron microscope to confirm that the external additive has disappeared, the surface of the magnetic toner mother particles can be observed with a scanning probe microscope. If the external additive has not been sufficiently removed, the surfaces of the magnetic toner mother particles are observed with SEM after repeating (2) and (3) until the external additive is sufficiently removed. As another method for removing the external additive in place of the above (2) and (3), there is a method of dissolving the external additive with an alkaline solution. As the alkali, an aqueous sodium hydroxide solution is preferred.

In the case of non-magnetic toner: 160 g of sucrose (manufactured by Kishida Chemical) is added to 100 mL of ion-exchanged water, and dissolved with a water bath to prepare a sucrose concentrate. A sucrose concentrate 31 g and 6 mL of Contaminone N are put into a centrifuge tube to prepare a dispersion. 1 g of toner is added to this dispersion and the mass of toner is loosened with a spatula or the like.

  The centrifuge tube is shaken with the above shaker at 350 reciprocations per minute for 20 minutes. After shaking, the solution is replaced with a glass tube (50 mL) for a swing rotor, and centrifuged with a centrifuge at 3500 rpm for 30 minutes. In the glass tube after centrifugation, toner base particles are present in the uppermost layer and silica fine particles are present in the lower aqueous solution side, so that only the toner base particles in the uppermost layer are collected.

  If the external additive has not been sufficiently removed, centrifugation is repeated as necessary, and after sufficient separation, the toner liquid is dried and toner base particles are collected.

  The measurement of the white area ratio is as follows.

  The toner base particle image is obtained as an SE image at a photographing magnification of 2000 times with a Hitachi ultra-high resolution field emission scanning electron microscope S-4800 (Hitachi High-Technologies Corporation). In addition, the imaging conditions are an acceleration voltage of 2.0 kV, an acceleration current of 10.0 μA, a probe current of Normal, a focus mode of UHR, and a WD of 5.0 mm. Since the subsequent image processing is performed on 100 toner particles, the number of images sufficient to obtain 100 clear toner mother particle images is acquired as an image.

  The white area ratio is calculated by analyzing the obtained image using image analysis software image processing software ImageJ (developer Wayne Rand). The measurement procedure is shown below.

  0.8 ≦ R / D4 ≦ with respect to the mass-based equivalent-circle weight average diameter D4 (μm) of the toner measured by a particle size distribution measuring apparatus “Coulter Counter Multisizer 3” (registered trademark, manufactured by Beckman Coulter, Inc.) 100 toners having a long diameter R (μm) satisfying the relationship of 1.2 are selected. As shown in FIG. 4, an image analysis area is selected as a relatively flat portion (field of view in which the entire observation surface is in focus) of the major axis R / 2 (μm) from the center of gravity of the toner surface on which the surface is observed.

The analysis procedure using image processing software
1) Display the outline of the toner base particles in [Process]-[Find Edge].
2) Binarize with [Image]-[Adjust]-[Threshold], confirm that the contours of the toner base particles are connected by a single line, determine the threshold value, and [Apply].
3) Select [Analyze]-[Analyze Particle], set the range of [Size (pixel∧2)] to 10-infinity, and set the range of [Circularity] from 0.00 to 1.00. Furthermore, Masks is selected in [Show], and a check mark is entered in [include holes].
4) Then, in [Edit]-[Paste Control], select [Transparent-White] in Transfer Mode, and copy it in [Edit]-[Copy].
5) Open the original image with [File]-[Open], and paste the image created and copied in 4) with [Edit]-[Paste].
6) Invert [Monochrome] with [Edit]-[Invert].
7) Set a threshold value by [Image]-[Adjust]-[Threshold], and [Apply]. (Set the value so that no noise remains on the contour of the toner base particle surface to be measured)
8) Check [Area] in [Analyze]-[Set Measurements].
9) Specify the range of the image analysis area, record the value of 0 (white) and the total count number in [Analyze]-[Histogram]-[List], and calculate the white area ratio of one toner base particle. calculate.
10) The same measurement is performed on 100 toner base particles to be measured, and the average value is the white area ratio of the present invention.

<Measuring method of softening point of toner and amorphous polyester>
The softening point of the toner and amorphous polyester is measured using a constant load extrusion type capillary rheometer “Flow Characteristic Evaluation Apparatus Flow Tester CFT-500D” (manufactured by Shimadzu Corporation) according to the manual attached to the apparatus. In this device, while applying a constant load from the top of the measurement sample with the piston, the measurement sample filled in the cylinder is heated and melted, and the melted measurement sample is pushed out from the die at the bottom of the cylinder, and the piston drop amount at this time A flow curve showing the relationship between temperature and temperature can be obtained.

  In the present invention, the “melting temperature in the 1/2 method” described in the manual attached to the “flow characteristic evaluation apparatus Flow Tester CFT-500D” is the softening point. The melting temperature in the 1/2 method is calculated as follows. First, ½ of the difference between the piston lowering amount Smax at the time when the outflow ends and the piston lowering amount Smin at the time when the outflow starts is obtained (this is X. X = (Smax−Smin) / 2). And the temperature of the flow curve when the amount of descending piston is the sum of X and Smin in the flow curve is the melting temperature in the 1/2 method.

  The measurement sample was about 1.0 g of toner or amorphous polyester at about 10 MPa using a tablet compression machine (for example, NT-100H, manufactured by NPA System) in an environment of 25 ° C., about 60 A cylinder having a diameter of about 8 mm and compression-molded for 2 seconds is used.

The measurement conditions of CFT-500D are as follows.
Test mode: Temperature rising start temperature: 50 ° C
Achieving temperature: 200 ° C
Measurement interval: 1.0 ° C
Temperature increase rate: 4.0 ° C./min
Piston cross-sectional area: 1.000 cm ²
Test load (piston load): 10.0 kgf (0.9807 MPa)
Preheating time: 300 seconds Die hole diameter: 1.0 mm
Die length: 1.0mm

<Measurement method of true density of toner base particles>
When measuring the true density of toner base particles in a toner in which an external additive is externally added to the toner base particles, it is necessary to remove the external additive. As a specific method, <white toner base particle It is as described in <Measurement method of partial area ratio>.

The true density of the toner base particles was measured by a dry automatic densimeter autopycnometer (manufactured by Yuasa Ionics). The conditions are as follows.
Cell: SM cell (10 ml)
Sample amount: About 2.0g

  This measurement method measures the true density of a solid / liquid based on a gas phase substitution method. Similar to the liquid phase replacement method, it is based on Archimedes' principle, but uses a gas (argon gas) as a replacement medium, and therefore has high accuracy for micropores.

<Measuring method of weight average particle diameter (D4) and number average particle diameter (D1) of toner>
The weight average particle diameter (D4) and number average particle diameter (D1) of the toner are measured by a fine particle size distribution measuring apparatus “Coulter Counter Multisizer 3” (registered trademark, Beckman Measurement and analysis were carried out using a dedicated software “Beckman Coulter Multisizer 3 Version 3.51” (manufactured by Beckman Coulter) for measurement condition setting and measurement data analysis. .

  As the electrolytic aqueous solution used for the measurement, special grade sodium chloride is dissolved in ion-exchanged water so as to have a concentration of about 1% by mass, for example, “ISOTON II” (manufactured by Beckman Coulter, Inc.) can be used.

  Prior to measurement and analysis, dedicated software was set up as follows.

  In the “Standard Measurement Method (SOM) Change Screen” of the dedicated software, set the total count in the control mode to 50000 particles, set the number of measurements once, and set the Kd value to “standard particles 10.0 μm” (Beckman Coulter, Inc.) Set the value obtained using The threshold and noise level are automatically set by pressing the threshold / noise level measurement button. Also, the current is set to 1600 μA, the gain is set to 2, the electrolyte is set to ISOTON II, and the aperture tube flash after measurement is checked.

  In the “pulse to particle size conversion setting screen” of the dedicated software, the bin interval is set to logarithmic particle size, the particle size bin is set to 256 particle size bin, and the particle size range is set to 2 μm to 60 μm.

The specific measurement method is as follows.
(1) About 200 ml of the electrolytic aqueous solution is put in a glass 250 ml round bottom beaker exclusively for ultisizer 3, set on a sample stand, and the stirrer rod is stirred counterclockwise at 24 rpm. Then, the dirt and bubbles in the aperture tube are removed by the “aperture flush” function of the dedicated software.
(2) About 30 ml of the electrolytic aqueous solution is put in a glass 100 ml flat bottom beaker, and "Contaminone N" (nonionic surfactant, anionic surfactant, organic builder pH 7 precision measurement is used as a dispersant therein. About 0.3 ml of a diluted solution obtained by diluting a 10% by weight aqueous solution of a neutral detergent for washing a vessel (made by Wako Pure Chemical Industries, Ltd.) 3 times with ion exchange water is added.
(3) Two oscillators with an oscillation frequency of 50 kHz are incorporated in a state where the phase is shifted by 180 degrees, and placed in a water tank of an ultrasonic disperser “Ultrasonic Dispersion System Tetora 150” (manufactured by Nikkiki Bios) with an electrical output of 120 W. A fixed amount of ion-exchanged water is added, and about 2 ml of the above-mentioned Contaminone N is added to this water tank.
(4) The beaker of (2) is set in the beaker fixing hole of the ultrasonic disperser, and the ultrasonic disperser is operated. And the height position of a beaker is adjusted so that the resonance state of the liquid level of the electrolyte solution in a beaker may become the maximum.
(5) In a state where the electrolytic aqueous solution in the beaker of (4) is irradiated with ultrasonic waves, about 10 mg of toner is added to the electrolytic aqueous solution little by little and dispersed. Then, the ultrasonic dispersion process is continued for another 60 seconds. In ultrasonic dispersion, the temperature of the water tank is appropriately adjusted so as to be 10 ° C. or higher and 40 ° C. or lower.
(6) To the (1) round bottom beaker installed in the sample stand, the (5) electrolytic aqueous solution in which the toner is dispersed is dropped using a pipette, and the measured concentration is adjusted to about 5%. The measurement is performed until the number of measured particles reaches 50,000.
(7) The measurement data is analyzed with the dedicated software attached to the apparatus, and the weight average particle diameter (D4) and the number average particle diameter (D1) are calculated. When the graph / number% and graph / volume% are set in the dedicated software, the “arithmetic diameter” on the analysis / number statistics (arithmetic average) and analysis / volume statistics (arithmetic average) screens is the number average. The particle diameter (D1) and the weight average particle diameter (D4).

<Calculation method of surface roughness index B / A>
The surface roughness index is obtained from the theoretical specific surface area A and BET specific surface area B of the toner base particles (= B / A). In addition, when measuring the surface roughness index of the toner base particles in a toner in which an external additive is externally added to the toner base particles, it is necessary to remove the external additive. It is as having described in the measuring method of the white part area ratio of particle | grains>.

  Each calculation method is as follows.

<< Calculation Method of Theoretical Specific Surface Area A of Toner Base Particles >>
In the same manner as the measurement of the number average particle diameter (D1), the number-based particle size distribution of the toner base particles was measured. However, in the analysis using “Beckman Coulter Multisizer 3 Version 3.51” (manufactured by Beckman Coulter, Inc.), the measurement target is 2.0 μm to 32.0 μm, and 12 channels (2.00 to 2.520 μm, 2.520 to 3.175 μm, 3.175 to 4.0000 μm, 4.000 to 5.040 μm, 5.040 to 6.350 μm, 6.350 to 8.000 μm, 8.000 to 10.079 μm, 10. 079 to 12.699 μm, 12.699 to 16.000 μm, 16.000 to 20.159 μm, 20.159 to 25.398 μm, 25.398 to 32.000 μm) to obtain the number-based particle size distribution. It was.

Thereafter, using the median value of each channel (for example, if it is 2.00 to 2.520 μm, the median value is 2.260 μm), the toner base particles of the median value of each channel are true spheres. The assumed theoretical surface area (= 4 × π × (median value of each channel) ² ) is obtained. By multiplying the theoretical surface area by the number ratio of the particles belonging to each channel obtained previously, the average theoretical surface area (a) of one particle when the measured toner base particle is assumed to be a true sphere is obtained.

Next, in the same way, the theoretical mass (= 4/3 × π) assuming that the toner base particles of each channel median are true spheres from the median value of each channel and the true density of the measured toner base particles. X (median value of each channel) ³ x true density). The average theoretical mass (b) of one particle is determined from the theoretical mass and the ratio of the number of particles belonging to each channel determined previously.

  The theoretical specific surface area A (= a / b) of the toner base particles is calculated from the average theoretical surface area and average theoretical mass of one particle.

<< Measurement Method of BET Specific Surface Area B of Toner Base Particles >>
The specific surface area BET of the toner base particles can be determined by a low temperature gas adsorption method by a dynamic constant pressure method according to a BET method (preferably a BET multipoint method). For example, by using a specific surface area measuring device “Gemini 2375 Ver. 5.0” (manufactured by Shimadzu Corporation), nitrogen gas is adsorbed on the sample surface, and measurement is performed using the BET multipoint method. m ² / g) was calculated. Specifically, the measurement is performed according to the following procedure.

  After measuring the mass of the empty sample cell, 1.0 g of the measurement sample is filled in the sample cell. Further, the sample cell filled with the sample is set in the degassing apparatus, and degassing is performed at room temperature for 7 hours. After completion of degassing, the mass of the entire sample cell is measured, and the accurate mass of the sample is calculated from the difference from the empty sample cell. Next, empty sample cells are set in the balance port and analysis port of the BET measuring apparatus. A dewar bottle containing liquid nitrogen is set at a predetermined position, and P0 is measured by a saturated vapor pressure (P0) measurement command. After the P0 measurement is completed, the sample cell prepared for degassing is set in the analysis port, and after inputting the sample mass and P0, the measurement is started by the BET measurement command. After that, the BET specific surface area is automatically calculated.

<Method of measuring the degree of hydrophobicity of the treated magnetic material>
The degree of hydrophobicity of the treated magnetic material is determined from a methanol drop transmittance curve obtained as follows.

  First, in order to remove bubbles and the like in the measurement sample, 70 ml of a hydrated methanol solution composed of 40% by volume of methanol and 60% by volume of water is placed in a cylindrical glass container having a diameter of 5 cm and a thickness of 1.75 mm. Disperse for 5 minutes with an ultrasonic disperser.

  Next, the treated magnetic material is shaken with a mesh having an opening of 150 μm, 0.2 g of the treated magnetic material that has passed through the mesh is precisely weighed, added to the container containing the hydrated methanol solution, and the sample solution for measurement is added. Prepare.

Then, the measurement sample solution is set in a powder wettability tester “WET-100P” (manufactured by Reska). The sample liquid for measurement is stirred at a speed of 6.7 s ⁻¹ (400 rpm) using a magnetic stirrer. As the rotor of the magnetic stirrer, a spindle type rotor having a length of 25 mm and a maximum barrel diameter of 8 mm coated with a fluororesin is used.

  Next, the transmittance was measured with light having a wavelength of 780 nm while continuously adding methanol to the measurement sample solution at a dropping rate of 1.3 ml / min through the above-described apparatus, as shown in FIG. Create a methanol drop transmission curve.

<Measuring method of toner average circularity and aspect ratio>
The average circularity of the toner and the aspect ratio of the toner are measured by the flow type particle image analyzer “FPIA-3000” (manufactured by Sysmex Corporation) under the measurement and analysis conditions during the calibration operation.

  A specific measurement method is as follows.

  First, about 20 ml of ion-exchanged water from which impure solids are removed in advance is put in a glass container. In this, "Contaminone N" (nonionic surfactant, anionic surfactant, 10% by weight aqueous solution of neutral detergent for pH7 precision measuring instrument cleaning, made by organic builder, manufactured by Wako Pure Chemical Industries, Ltd. About 0.2 ml of a diluted solution obtained by diluting the solution with ion exchange water about 3 times by mass. Further, about 0.02 g of a measurement sample is added, and dispersion treatment is performed for 2 minutes using an ultrasonic disperser to obtain a dispersion for measurement. In that case, it cools suitably so that the temperature of a dispersion liquid may become 10 to 40 degreeC. As the ultrasonic disperser, a desktop type ultrasonic cleaner disperser (for example, “VS-150” (manufactured by VervoCrea)) having an oscillation frequency of 50 kHz and an electric output of 150 W is used. Ion exchange water is added, and about 2 ml of the above-mentioned Contaminone N is added to this water tank.

  For the measurement, the above-mentioned flow type particle image analyzer equipped with “LUCPLFLN” (magnification 20 ×, numerical aperture 0.40) as an objective lens is used, and particle sheath “PSE-900A” (manufactured by Sysmex Corporation) is used as the sheath liquid. Is used. The dispersion prepared in accordance with the above procedure is introduced into the flow type particle image analyzer, and 2000 toners are measured in the HPF measurement mode and in the total count mode. Then, the binarization threshold at the time of particle analysis is set to 85%, the analysis particle diameter is limited to a circle equivalent diameter of 1.977 μm or more and less than 39.54 μm, and the average circularity and aspect ratio of the toner are obtained.

  In measurement, automatic focus adjustment is performed using standard latex particles (for example, “RESEARCH AND TEST PARTICLES Latex Microsphere Suspensions 5100A” manufactured by Duke Scientific) diluted with ion-exchanged water before starting the measurement. Thereafter, it is preferable to perform focus adjustment every two hours from the start of measurement.

  In the embodiment of the present application, a flow type particle image analyzer which has been issued a calibration certificate issued by Sysmex Corporation, which has been calibrated by Sysmex Corporation, is used. The measurement is performed under the measurement and analysis conditions when the calibration certificate is received, except that the analysis particle diameter is limited to a circle equivalent diameter of 1.977 μm or more and less than 39.54 μm.

<Measurement method of peak molecular weight Mp (P) of amorphous polyester>
The molecular weight distribution of the THF-soluble matter of the amorphous polyester is measured by gel permeation chromatography (GPC) as follows.

First, the target sample is dissolved in tetrahydrofuran (THF) over 24 hours at room temperature. The obtained solution is filtered through a solvent-resistant membrane filter “Maescho Disc” (manufactured by Tosoh Corporation) having a pore diameter of 0.2 μm to obtain a sample solution. The sample solution is adjusted so that the concentration of the component soluble in THF is about 0.8% by mass. Using this sample solution, measurement is performed under the following conditions.
Apparatus: HLC8120 GPC (detector: RI) (manufactured by Tosoh Corporation)
Column: Seven series of Shodex KF-801, 802, 803, 804, 805, 806, 807 (manufactured by Showa Denko KK)
Eluent: Tetrahydrofuran (THF)
Flow rate: 1.0 ml / min
Oven temperature: 40.0 ° C
Sample injection volume: 0.10 ml

  In calculating the molecular weight of the sample, standard polystyrene resin (for example, trade name “TSK Standard Polystyrene F-850, F-450, F-288, F-128, F-80, F-40, F-20, F— 10, F-4, F-2, F-1, A-5000, A-2500, A-1000, A-500 ", manufactured by Tosoh Corporation), and a molecular weight calibration curve is used.

<75% area ratio and measuring method of domain area ratio>
The toner is sufficiently dispersed in a visible light curable resin (Aronix LCR series D800), and then cured by irradiation with short wavelength light. The obtained cured product is cut out with an ultramicrotome equipped with a diamond knife to produce a 250-nm flaky sample. Next, the cut out sample was magnified at a magnification of 40000 to 50000 times using a transmission electron microscope (Electron Microscope JEM-2800 manufactured by JEOL Ltd.) (TEM-EDX), the cross section of the particle was observed, and EDX was used. Perform element mapping.

  The cross section of the toner to be observed is selected as follows. First, the cross-sectional area of the toner is obtained from the cross-sectional image of the toner, and the diameter (equivalent circle diameter) of a circle having an area equal to the cross-sectional area is obtained. Only a toner cross-sectional image in which the absolute value of the difference between the equivalent circle diameter and the weight average particle diameter (D4) of the toner is within 1.0 μm is observed.

  The mapping conditions are a storage rate of 9000 to 13000 and an integration count of 120. Among the domains derived from the resin confirmed from the observed image, the spectrum intensity derived from the C element and the spectrum intensity derived from the O element are measured. It is a domain of amorphous polyester. After identifying the amorphous polyester domain, the binarization process is performed to determine the distance between the contour and the center point of the cross section from the contour of the cross section of the toner to the total area of the amorphous polyester domains existing in the cross section of the toner. The area ratio (area%) of the amorphous polyester domains existing within 25% of the above is calculated. For the binarization process, Image Pro PLUS (manufactured by Nippon Roper Co., Ltd.) is used.

  The calculation method is as follows. In the TEM image, the contour and center point of the toner cross section are obtained. The outline of the toner cross section is assumed to be along the surface of the toner observed in the TEM image. The center point of the toner cross section is the center of gravity of the toner cross section.

  A line is drawn from the obtained center point to a point on the contour of the toner cross section. On the line, the position of 75% of the distance between the outline and the center point of the cross section is specified from the outline.

  Then, this operation is performed once for the contour of the toner cross section, and a boundary line of 75% of the distance between the contour and the center point of the cross section is clearly shown from the contour of the toner cross section.

  Based on the TEM image in which the 75% boundary line is clearly defined, the area of the amorphous polyester domain existing in the region surrounded by the outline of the toner cross section and the 75% boundary line is measured. . Then, the total area of the amorphous polyester domains present in the toner cross section is measured, and the area% based on the total area is calculated.

<Measuring method of number average particle diameter (D1) of domains of amorphous polyester>
Elemental mapping is performed using EDX in the same manner as described above to specify an amorphous polyester domain.

  The number average particle diameter of the domain is obtained by calculating the equivalent circle diameter from the area of the domain. The number of measurements is 100, and the arithmetic average value of the equivalent circle diameters of 100 domains is the number average particle diameter of the domains. The toner for calculating the number average particle diameter of the domains is determined as follows.

  First, the cross-sectional area of the toner is obtained from the cross-sectional image of the toner, and the diameter (equivalent circle diameter) of a circle having an area equal to the cross-sectional area is obtained. The domain diameter is calculated only for the toner cross-sectional image in which the absolute value of the difference between the equivalent circle diameter and the weight average particle diameter (D4) of the toner is within 1.0 μm. Since the domain diameter may vary depending on the particle diameter of the toner, the average domain diameter can be calculated in this way.

<Method for Measuring Acid Value Av of Amorphous Polyester>
The acid value is the number of mg of potassium hydroxide necessary for neutralizing the acid contained in 1 g of the sample. The acid value of the amorphous polyester is measured according to JIS K 0070-1992. Specifically, it is measured according to the following procedure.

(1) Preparation of Reagent 1.0 g of phenolphthalein is dissolved in 90 ml of ethyl alcohol (95% by volume), and ion exchanged water is added to make 100 ml to obtain a phenolphthalein solution.

  7 g of special grade potassium hydroxide is dissolved in 5 ml of water, and ethyl alcohol (95% by volume) is added to make 1 L. In order not to touch carbon dioxide, etc., put in an alkali-resistant container and let stand for 3 days, then filter to obtain a potassium hydroxide solution. The obtained potassium hydroxide solution is stored in an alkali-resistant container. The factor of the potassium hydroxide solution was as follows: 25 ml of 0.1 mol / l hydrochloric acid was placed in an Erlenmeyer flask, a few drops of the phenolphthalein solution were added, titrated with the potassium hydroxide solution, and the hydroxide required for neutralization. Determined from the amount of potassium solution. As the 0.1 mol / l hydrochloric acid, one prepared according to JIS K 8001-1998 is used.

(2) Operation (A) Main test 2.0 g of the crushed amorphous polyester sample is precisely weighed into a 200 ml Erlenmeyer flask, and 100 ml of a mixed solution of toluene / ethanol (2: 1) is added and dissolved over 5 hours. To do. Subsequently, several drops of the phenolphthalein solution is added as an indicator, and titration is performed using the potassium hydroxide solution. The end point of titration is when the light red color of the indicator lasts for about 30 seconds.

(B) Blank test Titration is performed in the same manner as above except that no sample is used (that is, only a mixed solution of toluene / ethanol (2: 1) is used).

(3) The acid value is calculated by substituting the obtained result into the following formula.
A = [(C−B) × f × 5.61] / S
Here, A: acid value (mgKOH / g), B: addition amount (ml) of a potassium hydroxide solution in a blank test, C: addition amount (ml) of a potassium hydroxide solution in this test, f: potassium hydroxide Solution factor, S: sample (g).

<Measuring method of hydroxyl value OHv of amorphous polyester>
The hydroxyl value is the number of mg of potassium hydroxide required to neutralize acetic acid bonded to a hydroxyl group when 1 g of a sample is acetylated. The hydroxyl value of the amorphous polyester is measured according to JIS K 0070-1992. Specifically, it is measured according to the following procedure.

(1) Preparation of reagent 25 g of special grade acetic anhydride is placed in a 100 ml volumetric flask, pyridine is added to make a total volume of 100 ml, and shaken sufficiently to obtain an acetylating reagent. The obtained acetylating reagent is stored in a brown bottle so as not to come into contact with moisture, carbon dioxide gas and the like.

  Dissolve 1.0 g of phenolphthalein in 90 ml of ethyl alcohol (95% by volume), add ion exchanged water to make 100 ml, and obtain a phenolphthalein solution.

  Dissolve 35 g of special grade potassium hydroxide in 20 ml of water and add ethyl alcohol (95% by volume) to 1 L. In order not to touch carbon dioxide, etc., put in an alkali-resistant container and let stand for 3 days, then filter to obtain a potassium hydroxide solution. The obtained potassium hydroxide solution is stored in an alkali-resistant container. The factor of the potassium hydroxide solution was as follows: 25 ml of 0.5 mol / l hydrochloric acid was placed in an Erlenmeyer flask, a few drops of the phenolphthalein solution were added, titrated with the potassium hydroxide solution, and the hydroxide required for neutralization. Determined from the amount of potassium solution. As the 0.5 mol / l hydrochloric acid, one prepared according to JIS K 8001-1998 is used.

(2) Operation (A) Main test 1.0 g of a crushed amorphous polyester sample is precisely weighed into a 200 ml round bottom flask, and 5.0 ml of the acetylating reagent is accurately added to the sample using a whole pipette. At this time, if the sample is difficult to dissolve in the acetylating reagent, a small amount of special grade toluene is added and dissolved.

  A small funnel is placed on the mouth of the flask, and the bottom of the flask is immersed in a glycerin bath at about 97 ° C. and heated. At this time, in order to prevent the temperature of the neck of the flask from rising due to the heat of the bath, it is preferable to cover the base of the neck of the flask with a cardboard having a round hole.

  After 1 hour, the flask is removed from the glycerin bath and allowed to cool. After standing to cool, 1 ml of water is added from the funnel and shaken to hydrolyze acetic anhydride. The flask is again heated in the glycerin bath for 10 minutes for further complete hydrolysis. After cooling, wash the funnel and flask wall with 5 ml of ethyl alcohol.

  Add several drops of the phenolphthalein solution as an indicator and titrate with the potassium hydroxide solution. The end point of titration is when the light red color of the indicator lasts for about 30 seconds.

(B) Blank test Titration similar to the above operation is performed except that a sample of amorphous polyester is not used.
(3) Substituting the obtained results into the following formula to calculate the hydroxyl value.
A = [{(BC) × 28.05 × f} / S] + D
Here, A: hydroxyl value (mg KOH / g), B: addition amount (ml) of potassium hydroxide solution in blank test, C: addition amount (ml) of potassium hydroxide solution in this test, f: potassium hydroxide Solution factor, S: sample (g), D: acid value of amorphous polyester (mgKOH / g).

<Measurement of Interfacial Tension in Aqueous Tricalcium Phosphate Aqueous Solution of Amorphous Polyester Dissolved in Styrene / Butyl Acrylate = 80/20 (Weight Ratio) by Hanging Drop Method>
(1) Preparation of aqueous phase After adding 450 parts of 0.1 mol / L-Na ₃ PO ₄ aqueous solution to 720 parts of ion-exchanged water and heating to 60 ° C., 1.0 mol / L-CaCl ₂ aqueous solution 67 .7 parts are added to obtain an aqueous medium containing a dispersion stabilizer. Measure pH (hereinafter also referred to as water phase) and confirm that it is 6.0 ± 0.2.

(2) Preparation of oil phase 1 g of sample is added to 8 g of styrene and 2 g of n-butyl acrylate and dissolved to prepare a styrene / butyl acrylate dispersion (hereinafter also referred to as an oil phase).

(3) Interfacial tension measurement Interfacial tension was measured by the hanging drop method described below. Specifically, using a FACE solid-liquid interface analyzer Drop Master 700 manufactured by Kyowa Interface Science Co., Ltd. in an environment at a temperature of 25 ° C., measurement was performed with WIDE 1 as the field of view of the lens portion. First, the tip portion of a thin tube having an inner diameter of 0.4 mm is placed in the aqueous phase downward in the vertical direction. Next, the thin tube is connected to the syringe part. An oil phase prepared in advance is placed in the syringe part. Next, a syringe part is connected to Kyowa Interface Science Co., Ltd. AUTO DISPENSER AD-31, and an oil phase is extruded from a thin tube, A droplet can be created in a capillary tube front-end | tip part in an aqueous phase. Then, the interfacial tension is calculated from the shape of the droplet. The control and calculation method for creating droplets was performed using a measurement analysis system manufactured by Kyowa Interface Science Co., Ltd. Note that the density difference between the water phase and the oil phase necessary for the calculation was 0.10 g / cm 3, which is the density difference between water and styrene. The final measurement result of the interfacial tension was the average value of 10 measurements.

  Although the basic configuration and features of the present invention have been described above, the present invention will be specifically described below based on examples. However, this does not limit the embodiment of the present invention. Unless otherwise specified, the number of parts in the examples is based on mass.

<Preparation of Toner Carrier 1>
(Preparation of substrate 1)
The substrate 1 was prepared by applying a primer (trade name, DY35-051; manufactured by Toray Dow Corning Co., Ltd.) to a 6 mm diameter cored bar made of SUS304 and baking it.

(Production of elastic roller 1)
The substrate 1 prepared as described above was placed in a mold, and an addition-type silicone rubber composition in which the following materials were mixed was injected into a cavity formed in the mold.
・ Liquid silicone rubber material (trade name, SE6724A / B; manufactured by Toray Dow Corning)
100 parts carbon black (trade name, Toka Black # 4300; manufactured by Tokai Carbon Co., Ltd.)
15 parts ・ Silica particles as heat resistance imparting agent 0.2 part ・ Platinum catalyst 0.1 part

  Subsequently, the mold was heated to cure and cure the silicone rubber at a temperature of 150 ° C. for 15 minutes. After the base body 1 having the silicone rubber layer cured on the peripheral surface was removed from the mold, the base body 1 was further heated at a temperature of 180 ° C. for 1 hour to complete the curing reaction of the silicone rubber layer. In this way, the elastic roller 1 in which the silicone rubber elastic layer having a diameter of 12 mm was formed so as to cover the outer peripheral surface of the substrate was produced.

(Preparation of surface layer 1)
(Synthesis of isocyanate group-terminated prepolymer 1)
Polypropylene glycol polyol (trade name: Exenol 4030; manufactured by Asahi Glass Co., Ltd.) 100 with respect to 17.7 parts of tolylene diisocyanate (TDI) (trade name: Cosmonate T80; manufactured by Mitsui Chemicals) in a reaction vessel under a nitrogen atmosphere 0.0 g was gradually added dropwise while maintaining the temperature in the reaction vessel at 65 ° C. After completion of the dropping, the reaction was carried out at a temperature of 65 ° C. for 2 hours. The obtained reaction mixture was cooled to room temperature to obtain an isocyanate group-terminated prepolymer 1 having an isocyanate group content of 3.8% by mass.

(Synthesis of amino compound 1)
100.0 parts (1.67 mol) of ethylenediamine and 100 parts of pure water were heated to 40 ° C. while stirring in a reaction vessel equipped with a stirrer, a thermometer, a reflux tube, a dropping device, and a temperature controller. Next, while maintaining the reaction temperature at 40 ° C. or lower, 425.3 parts (7.35 mol) of propylene oxide was gradually added dropwise over 30 minutes. The reaction was further stirred for 1 hour to obtain a reaction mixture. The resulting reaction mixture was heated under reduced pressure to distill off water, and amino compound 1: 426 g was obtained.

As a material for the surface layer,
-Isocyanate-terminated prepolymer 1 617.9 parts-Amino compound 1 34.2 parts-Carbon black (trade name, MA230; manufactured by Mitsubishi Chemical Corporation) 117.4 parts-Urethane resin fine particles (trade name, Art Pearl C-400 ; Negami Kogyo Co., Ltd.)
130.4 parts were stirred and mixed.

  Next, methyl ethyl ketone (hereinafter also referred to as “MEK”) was added so that the total solid content ratio was 30% by mass, and then mixed in a sand mill. Subsequently, the viscosity was further adjusted to 10 cps or more and 13 cps or less with MEK to prepare a coating material for forming a surface layer.

  The previously produced elastic roller 1 was dipped in the surface layer forming paint to form a coating film of the paint on the surface of the elastic layer of the elastic roller 1 and dried. Further, the surface of the elastic layer was provided with a surface layer of 15 μm by heat treatment at a temperature of 150 ° C. for 1 hour, whereby the toner carrier 1 was produced.

<Example of production of long-chain monomer 1>
1200 g of aliphatic hydrocarbon having a peak value of 35 carbon atoms is placed in a glass cylindrical reaction vessel, 38.5 g of boric acid is added at a temperature of 140 ° C., and immediately an oxygen concentration of 50% by volume of air and 50% by volume of nitrogen is added. After blowing 10% by volume of mixed gas at a rate of 20 liters per minute and reacting at 200 ° C. for 3.0 hours, warm water was added to the reaction solution, followed by hydrolysis at 95 ° C. for 2 hours. The reaction was taken. 20 parts of the modified product was added to 100 parts of n-hexane to obtain a long-chain monomer 1 in which unmodified components were dissolved and removed. The obtained long-chain monomer 1 had a modification rate of 94% and a hydroxyl value of 92.4 mgKOH / g.

<Production Example of Amorphous Polyester APES1>
In a reaction vessel equipped with a nitrogen introduction tube, a dehydration tube, a stirrer, and a thermocouple, carboxylic acid component and alcohol component are adjusted as shown in Table 1 as raw material monomers, and then dibutyltin is used as a catalyst as a monomer. 1.5 parts are added per 100 parts in total. Subsequently, the temperature was quickly raised to 180 ° C. at normal pressure in a nitrogen atmosphere, and then polycondensation was performed by distilling off water while heating from 180 ° C. to 210 ° C. at a rate of 10 ° C./hour. After reaching 210 ° C., the pressure in the reaction vessel was reduced to 5 kPa or less, and polycondensation was performed at 210 ° C. and 5 kPa or less to obtain amorphous polyester APES1. At that time, the polymerization time was adjusted so that the peak molecular weight of the obtained amorphous polyester APES1 was a value shown in Table 1. Table 1 shows the physical properties of the amorphous polyester APES1.

<Production of Amorphous Polyester APES 2-19>
Amorphous polyesters APES2 to 19 were obtained in the same manner as amorphous polyester APES1, except that the raw material monomers and amounts used were changed as shown in Table 1. Table 1 shows the physical properties of these amorphous polyesters.

<Example of production of amorphous polyester (APES20)>
A four-necked flask equipped with a nitrogen introduction tube, a dehydration tube, a stirrer and a thermocouple, 100 g of bisphenol A ethylene oxide 2 mol adduct, 189 g of bisphenol A propylene oxide 2 mol adduct, 51 g of terephthalic acid, 61 g of fumaric acid, adipine 25 g of acid and 2 g of esterification catalyst (tin octylate) were added, subjected to condensation polymerization reaction at 230 ° C. for 8 hours, further reacted at 8 kPa for 1 hour, cooled to 160 ° C., 6 g of acrylic acid, 70 g of styrene, n- A mixture of 31 g of butyl acrylate and 20 g of a polymerization initiator (di-t-butyl peroxide) was added dropwise over 1 hour using a dropping funnel, and after the addition, the addition polymerization reaction was continued for 1 hour while maintaining at 160 ° C. The temperature is raised to 200 ° C. and held at 10 kPa for 1 hour, and then unreacted acrylic acid, By removing the emissions and butyl acrylate, to obtain an amorphous polyester (APES20) is a composite resin formed by bonding a vinyl polymer segment and a polyester polymerized segment.

<Production Example of Processed Magnetic Material 1>
During an aqueous ferrous sulfate solution, 1.10 eq of sodium hydroxide solution from 1.00 relative to iron element, the amount of P ₂ O ₅ to an iron element to be 0.15% by mass in terms of phosphorus, the iron element On the other hand, SiO ₂ in an amount of 0.50% by mass in terms of silicon element was mixed to prepare an aqueous solution containing ferrous hydroxide. The pH of the aqueous solution was 8.0, and an oxidation reaction was performed at 85 ° C. while blowing air to prepare a slurry liquid having seed crystals.

  Subsequently, ferrous sulfate aqueous solution is added to this slurry liquid so that it may become 0.90 to 1.20 equivalent with respect to the initial alkali amount (sodium component of caustic soda), and the slurry liquid is maintained at pH 7.6, and air is supplied. The oxidation reaction was promoted while blowing to obtain a slurry liquid containing magnetic iron oxide. After filtration and washing, the water-containing slurry is once taken out. At this time, take a small amount of water sample and measure the water content. Next, this water-containing sample was put into another aqueous medium without drying, stirred and redispersed with a pin mill while circulating the slurry, and the pH of the redispersed liquid was adjusted to about 4.8. Then, 1.6 parts of n-hexyltrimethoxysilane coupling agent was added to 100 parts of magnetic iron oxide with stirring (the amount of magnetic iron oxide was calculated as a value obtained by subtracting the water content from the water-containing sample), and water was added. Decomposition was performed. Thereafter, the surface treatment is carried out by sufficiently stirring and adjusting the pH of the dispersion to 8.6. The produced hydrophobic magnetic material is filtered with a filter press, washed with a large amount of water, dried at 100 ° C. for 15 minutes, and then at 90 ° C. for 30 minutes. The resulting particles are crushed to have a volume average particle size of 0. A treated magnetic body 1 of 21 μm was obtained.

<Production example of processed magnetic bodies 2 and 3>
Treated magnetic bodies 2 and 3 were obtained in the same manner as the treated magnetic body 1 except that the amount of the n-hexyltrimethoxysilane coupling agent was changed. Table 2 shows the physical properties of the processed magnetic bodies 1 to 3.

<Production Example of Toner Base Particle 1>
(Preparation of the first aqueous medium)
450 parts of 0.1 mol / L-Na ₃ PO ₄ aqueous solution was added to 720 parts of ion-exchanged water and heated to 60 ° C., and then 67.7 parts of 1.0 mol / L-CaCl ₂ aqueous solution was added to stabilize the dispersion. A first aqueous medium containing the agent was obtained.

(Preparation of polymerizable monomer composition)
・ Styrene 74 parts ・ N-butyl acrylate 26 parts ・ Divinylbenzene 0.5 part ・ Amorphous polyester resin 1 10 parts ・ Negative charge control agent T-77 (manufactured by Hodogaya Chemical) 1 part ・ Processed magnetic substance 1 65 parts The prescription is uniformly dispersed and mixed using an attritor (Mitsui Miike Chemical Co., Ltd.). This monomer composition was heated to a temperature of 60 ° C., and 15 parts of paraffin wax (HNP-9: manufactured by Nippon Seiwa Co., Ltd.) was used as a release agent, and t-butyl peroxypi was used as a polymerization initiator. 7 parts of barate (25% toluene solution) was mixed / dissolved to obtain a polymerizable monomer composition.

(Preparation of second aqueous medium)
After adding 150 parts of a 0.1 mol / L-Na ₃ PO ₄ aqueous solution to 360 parts of ion-exchanged water and heating to 60 ° C., 22.6 parts of a 1.0 mol / L-CaCl ₂ aqueous solution was added to stabilize the dispersion. A second aqueous medium containing the agent was obtained.

(Granulation / polymerization / filtration / drying)
The polymerizable monomer composition was introduced into the first aqueous medium, temperature 60 ° C., T. under N ₂ atmosphere K. The mixture is stirred for 15 minutes at 10,000 rpm with a homomixer (made by Tokushu Kika Kogyo Co., Ltd.) and granulated. Thereafter, the granulated liquid is added to the second aqueous medium, stirred with a paddle stirring blade, and subjected to a polymerization reaction at a reaction temperature of 70 ° C. for 300 minutes.

  At this point, hydrochloric acid was added to a small amount of sampled aqueous medium to remove calcium phosphate by washing, followed by filtration and drying to analyze the colored particles. As a result, the glass transition temperature Tg of the binder resin was 54 ° C.

  Subsequently, the aqueous medium in which the colored particles are dispersed is heated to 100 ° C. and held for 120 minutes. Then, 5 degreeC water is thrown into an aqueous medium, and it cools from 100 degreeC to 50 degreeC with the cooling rate of 300 degreeC / min. Subsequently, the aqueous medium was held at 50 ° C. for 120 minutes.

  Thereafter, hydrochloric acid was added to the aqueous medium to wash away calcium phosphate, followed by filtration and drying to obtain toner base particles 1. Table 3 shows the production conditions of the toner base particles 1.

<Production Example of Toner Base Particles 2 to 29>
In the production of the toner base particle 1, except that the amorphous polyester seed, addition amount, colorant seed, addition amount, dispersion stabilizer amount in the second aqueous medium, sodium chloride amount, and production conditions are changed. Similarly, toner mother particles 2 to 29 were produced. Table 3 shows the production conditions of the toner base particles obtained.

<Production Example of Toner Base Particle 30>
<< Preparation of each dispersion liquid >>
-Resin particle dispersion (1)-
-Styrene (Wako Pure Chemical Industries): 325 parts-n-butyl acrylate (Wako Pure Chemical Industries): 100 parts-Acrylic acid (Rhodia Nikka Co., Ltd.): 13 parts-1,10-decanediol diacrylate (new) Nakamura Chemical Co., Ltd.): 1.5 parts · Dodecanethiol (manufactured by Wako Pure Chemical Industries, Ltd.): 3.0 parts The above components are mixed in advance and dissolved to prepare a solution. An anionic surfactant (Dow Chemical) A surfactant solution prepared by dissolving 9 parts of Dowfax A211) in 580 parts of ion-exchanged water is placed in a flask, and 400 parts of the above solution is added, dispersed and emulsified, and slowly stirred for 10 minutes. While mixing, 50 parts of ion-exchanged water in which 6 parts of ammonium persulfate was dissolved was added.

  Next, after sufficiently replacing the inside of the flask with nitrogen, the flask was heated with an oil bath while stirring the flask until it reached 75 ° C., and emulsion polymerization was continued for 5 hours to obtain a resin particle dispersion (1). It was.

  When the resin particles were separated from the resin particle dispersion (1) and examined for physical properties, the number average particle diameter was 195 nm, the solid content in the dispersion was 42%, the glass transition point was 51.5 ° C., and the weight average molecular weight Mw. Was 32,000.

-Resin particle dispersion (2)-
The amorphous polyester (APES20) was dispersed using a disperser in which Cavitron CD1010 (manufactured by Eurotech Co., Ltd.) was modified to a high temperature and high pressure type. Specifically, the composition ratio is 79% ion-exchanged water, 1% anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd .: Neogen RK) (active ingredient), and the concentration of amorphous polyester 20 is 20%. Then, the pH was adjusted to 8.5 with ammonia, the Cavitron was operated under the conditions of a rotor rotation speed of 60 Hz, a pressure of 5 kg / cm ² and heating by a heat exchanger at 140 ° C., and a number average particle diameter of 200 nm. A resin fine particle dispersion (2) was obtained.

-Colorant dispersion-
・ Carbon black 20 parts ・ Anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd., Neogen R) 2 parts ・ Ion-exchanged water 78 parts The above components were used at 3000 rpm using a homogenizer (IKA, Ultra Turrax T50). After 2 minutes of blending the pigment in water and dispersing at 5000 rpm for 10 minutes, the mixture was stirred for one day with a normal stirrer and defoamed, and then a high-pressure impact disperser Ultimateizer (manufactured by Sugino Machine Co., Ltd.) HJP30006) was used and dispersed at a pressure of 240 MPa for about 1 hour to obtain a colorant dispersion (1). Further, the pH of the dispersion was adjusted to 6.5.

-Release agent dispersion-
・ 45 parts of hydrocarbon wax (Fischer-Tropsch wax, maximum endothermic peak = 78 ° C., Mw = 750)
・ Cationic surfactant (Neogen RK, Daiichi Kogyo Seiyaku) 5 parts ・ Ion-exchanged water 200 parts The above components were heated to 95 ° C. and sufficiently dispersed with a homogenizer (manufactured by IKA, Ultra Tarax T50). Dispersion treatment was performed with a pressure-discharge type gorin homogenizer to obtain a release agent dispersion having a number average diameter of 190 nm and a solid content of 25%.

<< Production Example of Toner Base Particles 28 >>
・ Ion-exchanged water 400 parts ・ Resin particle dispersion (1) 620 parts (resin particle concentration: 42%)
Resin particle dispersion (2) 279 parts (resin particle concentration: 20%)
Anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd., Neogen RK, active ingredient amount: 60%)
1.5 parts (0.9 parts as an active ingredient)
The above components were put into a 3 liter reaction vessel equipped with a thermometer, pH meter, and stirrer, and maintained at a temperature of 30 ° C. and a stirring rotation speed of 150 rpm for 30 minutes while controlling the temperature with a mantle heater from the outside. Thereafter, 88 parts of the colorant dispersion and 60 parts of the release agent dispersion were added and held for 5 minutes. As it was, a 1.0% nitric acid aqueous solution was added to adjust the pH to 3.0. Next, the stirrer and the mantle heater were removed, and 0.33 parts of polyaluminum chloride and 37.5 parts of 0.1% nitric acid aqueous solution were dispersed while being dispersed at 3000 rpm with a homogenizer (manufactured by IKA Japan: Ultratarax T50). After adding 1/2 of the mixed solution, the dispersion speed was set to 5000 rpm, the remaining 1/2 was added over 1 minute, and the dispersion speed was set to 6500 rpm, and dispersed for 6 minutes.

  A reactor is equipped with a stirrer and a mantle heater, and the temperature is increased to 42 ° C. at 0.5 ° C./min while appropriately adjusting the rotation speed of the stirrer so that the slurry is sufficiently stirred. After maintaining for 15 minutes, the particle size was measured with a Coulter Multisizer every 10 minutes while raising the temperature at 0.05 ° C./min. When the weight average particle size became 7.8 μm, 5% water The pH was adjusted to 9.0 using an aqueous sodium oxide solution. Thereafter, while adjusting the pH to 9.0 every 5 ° C., the temperature was raised to 96 ° C. at a temperature rising rate of 1 ° C./min and maintained at 96 ° C. When the particle shape and surface properties were observed every 30 minutes with an optical microscope and a scanning electron microscope (FE-SEM), the particles were almost spherical in the second hour. Solidified.

  Thereafter, the reaction product is filtered and washed with ion-exchanged water. When the filtrate has a conductivity of 50 mS or less, cake-like particles are taken out, and ion-exchanged water having an amount 10 times the particle weight is taken out. When the particles were sufficiently loosened by stirring with a three-one motor, the pH was adjusted to 3.8 with a 1.0% nitric acid aqueous solution and held for 10 minutes. Thereafter, filtration and washing with water were performed again, and when the conductivity of the filtrate became 10 mS or less, water flow was stopped and solid-liquid separation was performed. The obtained cake-like particles were pulverized by a sample mill and dried in an oven at 40 ° C. for 24 hours. Further, the obtained powder was pulverized with a sample mill, and then further vacuum dried in an oven at 40 ° C. for 5 hours to obtain toner base particles 30.

<Production Example of Toner Base Particle 31>
Toner base particles 31 were obtained according to Example 2 of Japanese Patent No. 4485382.

<Example of production of toner mother particles 32>
Toner base particles were produced according to Example 1 of JP-A-2005-184746, and toner base particles 32 were obtained.

[Example 1]
<Production of toner>
<Production Example of Toner 1>
To 100 parts of toner base particle 1, 0.3 part of sol-gel silica fine particles having a primary particle number average particle size of 115 nm was added and mixed using a Mitsui Henschel mixer (Mitsui Miike Chemical Co., Ltd.). Thereafter, silica having a number average particle size of 12 nm of primary particles is further treated with hexamethyldisilazane and then with silicone oil, and 0.9 part of hydrophobic silica fine particles having a BET specific surface area value of 120 m ² / g after treatment. In the same manner, Mitsui Henschel Mixer (manufactured by Mitsui Miike Chemical Co., Ltd.) was mixed and toner 1 was prepared. Table 4 shows the physical properties of Toner 1.

<Image forming apparatus>
A Canon printer LBP7700C was modified and used for image output evaluation. As a modification point, the toner carrier is changed to the toner carrier 1, and the toner supply member of the developing device is rotated reversely to the toner carrier as shown in FIG. 1, and voltage is applied to the toner supply member. Turn off. The contact pressure is adjusted so that the width of the contact portion between the toner carrier and the electrostatic latent image carrier is 1.0 mm.

  In addition, the cleaning blade is removed and the process speed is modified to 35 ppm. In this way, the area of the contact portion between the toner carrier and the electrostatic latent image carrier is reduced, and the process speed is increased, whereby strict image forming conditions are obtained. Also, the configuration of the fixing device was modified so that no voltage was applied to the fixing film during fixing. Thereby, the electrostatic offset can be viewed strictly.

The development device modified as described above is charged with 100 g of toner 1 and repeatedly in a low temperature and low humidity environment (15.0 ° C./10.0%) and a high temperature and high humidity environment (32.5 ° C./80% RH). Perform a usage test. As an output image for the repeated use test, a horizontal line image with a printing rate of 1% is printed on two sheets intermittently for 1000 sheets per day for a total of 4000 sheets (4 days). The evaluation results are shown in Table 5. The evaluation paper used for the repeated use test is a business 4200 (manufactured by Xerox) having a basis weight of 75 g / m ² .

  The evaluation methods and judgment criteria for each evaluation performed in the examples and comparative examples of the present invention will be described below.

<Fog on black drum after low temperature and low humidity>
The fog is measured using a REFECTMETER MODEL TC-6DS manufactured by Tokyo Denshoku. A green filter is used as the filter. “Foil on drum after black” outputs a solid black image immediately after printing 4000 sheets of the above-mentioned repeated use test, and indicates the area of the photosensitive drum corresponding to the white background (non-image portion) immediately after the transfer of the solid black image. Taped with Mylar tape and stripped, and Mylar tape was pasted on paper. The difference is calculated by subtracting the reflectivity of the mylar tape only on the unused paper from the reflectivity of the peeled off mylar tape on the unused paper.

In the present invention, C or higher was judged good.
A: Less than 5.0% B: 5.0% or more and less than 10.0% C: 10.0% or more and less than 15.0% D: 15.0% or more

<Evaluation of electrostatic offset resistance under low temperature and low humidity>
After the above-described repeated use test 4000 prints and the above black post fogging evaluation, 100 images were continuously printed using a solid black image in the first half and a white background in the second half of the image. The resistance to electrostatic offset is evaluated visually. In addition, the evaluation criteria of the electrostatic offset resistance are determined as follows.
A: Not seen at all.
B: Slightly seen in the white part.
C: It can be seen in the white part.
D: Clearly seen in the white part.

<Fog on the white rear drum in a high temperature and high humidity environment>
The fog is measured using a REFECTMETER MODEL TC-6DS manufactured by Tokyo Denshoku. A green filter is used as the filter. “Foil on drum after black” is an area of the photosensitive drum corresponding to a white background (non-image portion) immediately after the transfer of the solid white image by outputting a solid white image on the morning of the next day after printing 4000 sheets of the above repeated use test. The tape was stripped off with Mylar tape, and Mylar tape was pasted on the paper. The difference is calculated by subtracting the reflectivity of the mylar tape only on the unused paper from the reflectivity of the peeled off mylar tape on the unused paper.

In the present invention, C or higher was judged good.
A: Less than 5.0% B: 5.0% or more and less than 10.0% C: 10.0% or more and less than 15.0% D: 15.0% or more

<Contamination of charging roller under high temperature and high humidity>
During the above-described repeated use test 4000 sheets in a high temperature and high humidity environment, the state of the surface of the charging roller is visually observed every 1000 sheets (1 day). Thereafter, the electrostatic latent image carrier is replaced with a new one, a halftone image is output, and image evaluation is performed visually according to the following criteria.
A: Defects are not recognized at all on the roller surface and the image.
B: The surface of the roller is slightly stained on the morning of the following day after printing 4000 sheets, but no defect is seen in the halftone image output at that time.
C: Some smudges were observed on the surface of the roller in the morning the next day after printing 3000 sheets, and some density unevenness occurred in the halftone image output at that time.
D: Some dirt is observed on the surface of the roller the next morning after printing 3000 sheets, and density unevenness is conspicuous in the halftone image output at that time.

[Examples 2 to 27]
In the production example of the toner 1, the toner base particles are changed as shown in Table 4 to obtain toners 2-27. Table 4 shows the physical properties of each toner. Table 5 shows the evaluation results obtained in the same manner as in Example 1.

[Comparative Examples 1-5]
In the production example of the toner 1, the toner base particles are changed as shown in Table 4 to obtain toners 28 to 32. Table 4 shows the physical properties of each toner. Table 5 shows the evaluation results obtained in the same manner as in Example 1.

  45 electrostatic latent image carrier, 46 charging roller, 47 toner carrier, 48 toner supply member, 49 developing device, 50 transfer member (transfer roller), 51 fixing device, 52 pickup roller, 53 transfer material (paper), 54 Laser generator, 55 toner regulating member, 56 metal plate, 57 toner

Claims (9)

A toner having toner base particles containing a binder resin, an amorphous polyester and a colorant,
The binder resin contains a vinyl resin,
The toner has an average circularity of 0.960 or more,
The average white area area ratio obtained by binarizing the toner base particles observed with a scanning electron microscope (SEM) under the following conditions is 10.0% or less,
The theoretical specific surface area A (m ² / g) obtained from the particle size distribution and true density of the toner base particles and the specific surface area B (m ² / g) measured by the BET method are expressed by the following formula (1). ) And (2).
0.450 ≦ B ≦ 1.500 (1)
1.23 ≦ B / A ≦ 1.60 (2)
How to find the white area ratio [Shooting conditions]
Scanning electron microscope: S-4800
Magnification: 2000 times Image: SE image Acceleration voltage: 2.0 kV
Acceleration current: 10.0 μA
Probe current: Normal
Focus mode: UHR
WD: 5.0mm
[Area ratio measurement conditions]
Image processing software: Image J is used to perform binarization after the background of the captured image is all blackened, and the white area ratio in 50% of the particle diameter is calculated around the center of gravity of the toner.   The toner according to claim 1, wherein the toner has an aspect ratio of 0.910 or more.   The amorphous polyester has an interfacial tension of 25 to 35 mN / m in a tricalcium phosphate aqueous solution of pH 6 of the amorphous polyester dissolved in styrene / butyl acrylate = 80/20 (mass ratio). The toner according to claim 1. The relationship between the acid value Av (mgKOH / g) and the hydroxyl value OHv (mgKOH / g) of the amorphous polyester satisfies the following formulas (3) and (4). toner.
1.0 ≦ Av ≦ 4.0 (3)
2.0 ≦ Av + 0.1OHv ≦ 8.0 (4)   The amorphous polyester has a polycondensation polymer of an alcohol component and a carboxylic acid component containing 10 to 70 mol% of a linear aliphatic dicarboxylic acid having 6 to 12 carbon atoms. 5. The toner according to any one of 4 above.   The toner according to claim 1, wherein the toner has 5.0 to 30.0 parts by mass of the amorphous polyester with respect to 100 parts by mass of the binder resin.   The toner according to claim 1, wherein the toner base particles contain magnetic fine particles. In the cross section of the toner observed with a transmission electron microscope,
The vinyl resin forms a matrix, the amorphous polyester forms a domain,
2. The amorphous polyester domain is present in an area of at least 96 area% based on the total area of the domain within 75% of the distance between the outline and the center point of the cross section from the outline of the cross section. The toner according to any one of 7 to 7. In the cross section of the toner observed with a transmission electron microscope,
The vinyl resin forms a matrix, the amorphous polyester forms a domain,
The toner according to claim 1, wherein the amorphous polyester has a number average particle diameter of 0.3 μm or more and 3.0 μm or less.

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