JP2012103573A - Toner for electrostatic charge image development, and image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming apparatus and a toner having excellent low-temperature fixability, causing no toner aggregation even in a high humidity environment, capable of securing charging stability, suppressing filming and preventing image degradation.SOLUTION: The image forming apparatus includes charging means, exposing means, developing means, transfer means, fixing means and cleaning means, in which a toner used for forming an image is produced by an aqueous granulation process. The toner contains silica fine particles as an additive on a surface of a toner base, and the silica comprises porous silica fine particles having fine pores on the surface thereof. A coverage area ratio of the porous silica fine particles with respect to the toner base area is 5 to 20%. The porous silica fine particles have an average primary particle diameter of 20 to 200 nm, an absolute specific gravity of 2.0 g/cmor less, and a specific surface area of 20 to 500 m/g.

Description

  The present invention relates to a toner used as a developer and an image forming apparatus using the toner when developing an electrostatic image formed by electrophotography, electrostatic recording, or the like.

  The image forming apparatus forms an image with charging means (or apparatus) for uniformly charging the image forming area on the surface of the image carrier, exposure means for writing on the image carrier, and toner frictionally charged on the image carrier. The image is fixed on the printing paper after passing through the developing means, the transfer means for transferring the image on the image carrier directly to the printing paper or indirectly via the intermediate transfer body. Further, the untransferred toner remaining without being transferred onto the image carrier is scraped off from the image carrier by the cleaning means, and enters the next image forming process.

As the developer used, there are a two-component developer composed of a toner and a carrier and a one-component developer composed of only a magnetic or non-magnetic toner. These toners are generally produced by kneading and pulverizing a resin, a pigment, a charge control agent and a release agent by melting and kneading and then cooling and pulverizing and classifying them. It is difficult to control.
Under such circumstances, recently, there has been an attempt to control the particle size of toner particles intentionally to solve the above-mentioned problems, and polymerized toner methods such as emulsion polymerization method and dissolution suspension method as aqueous granulation. Became popular.

  In recent years, there has been an increasing demand for higher image quality, and in particular, in order to realize high-definition images in color image formation, there has also been an increasing demand for toner diameter reduction and particle size uniformity. When an image is formed using a toner having a wide particle size distribution, the problem that the fine powder toner contaminates the developing roller, charging roller, charging blade, photosensitive member, carrier, etc., or the toner scatters increases, resulting in high image quality. And it was difficult to achieve high reliability at the same time. On the other hand, when the particle size is uniform and the particle size distribution is sharp, the development behavior of the individual toner particles is uniform, and the reproducibility of minute dots is greatly improved.

As a fixing method in the electrophotographic method, a heating heat roller method in which a heating roller is directly pressed against a toner image on a recording medium and fixed is widely used from the viewpoint of energy efficiency. The heating heat roller system requires a large amount of power for fixing.
Therefore, various studies have been made to reduce the power consumption of the heating roller from the viewpoint of energy saving. For example, a method is generally used in which the output of the heater for the heating roller is weakened when the image is not output and the output of the heater is increased to increase the temperature of the heating roller when the image is output.
However, in this case, in order to raise the temperature of the heating roller to the temperature necessary for fixing from the sleep time, a waiting time of about several tens of seconds is required, and this waiting time becomes a stress for the user. In addition, when the image is not output, it is desired to suppress power consumption by completely turning off the heater. In order to achieve these requirements, it is necessary to lower the fixing temperature of the toner itself and lower the fixing temperature of the toner when it can be used.

The toner used in the developer is required to have excellent low-temperature fixability and storage stability (blocking resistance) with the development of electrophotographic technology, and has been generally used as a binder resin for toner. Various attempts have been made to use a polyester resin having a higher affinity with a recording medium or the like than a styrene-based resin and excellent in low-temperature fixability.
However, when designing a toner with an emphasis on low-temperature fixability, the storability is in a trade-off relationship, and both are necessary.
In order to solve these problems, a capsule structure composed of core particles containing a resin having a low glass transition temperature and an outer shell containing a resin having a high glass transition temperature formed so as to cover the surface of the core particles. Toners have been devised.
For example, a mixed liquid of a core constituent material containing a monomer (polymerizable monomer) that is a raw material of a thermoplastic resin and an outer shell constituent material containing amorphous polyester is dispersed in a dispersion medium. In addition, a capsule toner in which an outer shell is formed by an in-situ polymerization method in which the outer shell constituent material is unevenly distributed on the surface of the droplet as the core particles are formed by polymerization has been proposed (Japanese Patent No. 3030741). reference).
Further, by adding an aqueous dispersion of resin fine particles obtained by emulsion polymerization or soap-free emulsion polymerization to polymer particles (core particles) obtained by suspension polymerization, 95% or more of the surface of the polymer particles is obtained. There has been proposed a toner which is coated with fine particles and then heated to a temperature higher than the glass transition temperature of the polymer particles so as to have a surface substantially free of bulges (see Japanese Patent Application Laid-Open No. 2000-112174).
Also, a coating resin is provided by mixing at least two kinds of resin fine particles having different glass transition temperatures and a toner core material (core particle), and fixing or fusing the resin particles on the toner core material while raising the temperature. Toners have been proposed (see JP 2001-201891 A).
Further, the surface of a core toner (core particle) made of a binder resin having an average particle diameter of 2 to 20 μm and a glass transition temperature of 30 to 55 ° C. is coated or fixed or fused with a resin fine particle encapsulating wax. There has been proposed a toner obtained by a process including a first stage process to be carried out and a second stage process in which resin fine particles not containing wax are coated and fixed or fused (Japanese Patent Application Laid-Open No. 2004-320542). 2001-235894).
However, in the above-mentioned patent documents, storage stability at high temperatures, blocking resistance and aggregation properties are described, but storage stability and aggregation properties in a high humidity environment are not mentioned at all, and measures are taken. It is not done. Therefore, it is considered that the storage stability as a toner is still incomplete.

Further, the concern for the high humidity environment is not limited to the storage stability. The effect on the toner charge amount is very large and cannot be ignored.
The toner charge amount change due to temperature and humidity changes will be described in detail. The toner charge amount of the developer changes depending on the moisture absorption state of the developer, the toner charge amount is high in a low humidity environment, and the toner charge amount in a high humidity environment. The amount tends to be low.
This toner charge amount change has a large effect on image quality stabilization, especially image density stabilization. Conventionally, a temperature / humidity sensor has been installed around the developing machine to solve this problem. In the image forming apparatus for forming the electrostatic latent image by uniformly charging the carrier and changing the charging potential, the charging condition of the image carrier before forming the electrostatic latent image, the developing bias applied to the developing device By adjusting image forming conditions such as a transfer current in other development conditions such as the above, a change in image density with respect to a change in temperature and humidity and a change in toner charge amount caused thereby has been prevented.
The change in the toner charge amount may affect the toner density control of the developer, and as a countermeasure, a technique as disclosed in Japanese Patent Application Laid-Open No. 2001-215663 is disclosed.
In other words, the image forming conditions have been controlled in anticipation of the change in toner charge amount with respect to the change in temperature and humidity from the detection value of the temperature and humidity sensor installed in the vicinity of the developing device.

However, even if it is possible to keep the toner concentration at a certain level, if there is a change in the triboelectric charge amount of the toner as the environment changes, the toner charge amount changes even if the developer concentration is kept at a certain level. It cannot follow the fluctuation of image density due to.
Further, a large variation in the toner charge amount indicates that the amount of change in the repulsive force between the developer particles is large. The repulsive force between the developer particles is more likely to be repelled as the toner charge amount is larger, and the repulsion spreads between the developer particles, thereby reducing the bulk density of the developer. This decrease indicates that the change in the bulk density of the developer is large, and it is difficult to use the toner concentration detection sensor.
As described above, in an image forming apparatus equipped with toner, it is very difficult to suppress a change in charge amount of the toner due to a change in temperature and humidity. Therefore, the toner itself is designed not to be affected by the change in temperature and humidity. Is required.

  Therefore, in Japanese Patent Application Laid-Open No. 2-73362 of Patent Document 6 and Japanese Patent Application Laid-Open No. 2008-76421 of Patent Document 7, silica gel is contained in the toner resin and in the surface layer portion to suppress the change in the charge amount with respect to the temperature and humidity change. However, these techniques relate to pulverized toners, not so-called chemical toners. In addition, since the amount of silica gel added is excessive in this toner, the silica gel on the photoconductor is developed during development. Is liberated, and there is a concern that the free silica gel promotes adhesion of foreign matter (hereinafter referred to as filming) that adheres to the surface of the photoconductor, promotes wear of the photoconductor, and deteriorates image quality.

An object of the present invention is to provide a toner that solves the above-described conventional problems.
That is, an object of the present invention is to have excellent low-temperature fixability, no toner aggregation occurs even in a high humidity environment, charging stability can be ensured, and filming can be suppressed to prevent image deterioration. An image forming apparatus and a toner are provided.

The above-described problems are solved by the present invention including the following image forming apparatuses (1) to (15), an image forming method, and toner for them.
(1) In an image forming apparatus having a charging unit, an exposure unit, a developing unit, a transfer unit, a fixing unit, and a cleaning unit.
The toner used for image formation is a toner prepared by aqueous granulation, and has silica fine particles as an additive on the surface of the toner base, and the silica is porous silica fine particles having fine pores on the surface, The ratio of the coating area of the porous silica fine particles to the toner base surface is 5 to 20%, the average primary particle size of the porous silica fine particles is 20 to 200 nm, and the true specific gravity is 2.0 g / cm ³ or less. An image forming apparatus having a specific surface area of 20 to 500 m ² / g.
(2) The image forming apparatus according to item (1), wherein the toner has a binder resin as a binder resin.
(3) The image according to item (1) or (2), wherein the toner contains at least one crystalline polyester resin and at least one amorphous polyester resin as a binder resin component. Forming equipment.
(4) The toner contains at least a part of interlayer ions in a binder resin, a prepolymer composed of a modified polyester resin, a compound that undergoes an elongation reaction or a crosslinking reaction with the prepolymer, a colorant, a release agent, and a layered inorganic mineral. Toner solution or dispersion containing modified layered inorganic mineral modified with organic ions in organic solvent is emulsified or dispersed in an aqueous medium to remove the solvent from the resulting dispersion. Any of (1) to (3) above, wherein the solution of the organic solvent or the dispersion thereof has a Casson yield value at 25 ° C. of 1 Pa to 100 Pa. An image forming apparatus according to claim 1.
(5) The image forming apparatus according to any one of (1) to (4), wherein an average circularity A of toner base particles of the toner is in a range of 0.94 ≦ A ≦ 0.99.
(6) In an image forming method having at least an image carrier and a charging step, an exposure step, a development step, a transfer step, a fixing step, and a cleaning step, the toner used for the image formation is produced by aqueous granulation. The toner has silica fine particles as an additive on the surface of the toner base, the silica is porous silica fine particles having fine pores on the surface, and the ratio of the coverage area of the porous silica fine particles to the surface of the toner base is 5 to 20%, the average primary particle size of the porous silica fine particles is 20 to 200 nm, the true specific gravity is 2.0 g / cm ³ or less, and the specific surface area is 20 to 500 m ² / g. An image forming method.
(7) The image forming method as described in (6) above, wherein the toner binder resin is a polyester resin.
(8) The toner according to (6) or (7), wherein the toner contains at least one crystalline polyester resin and at least one amorphous polyester resin as a binder resin component. The image forming method according to any one of the above.
(9) The toner contains at least a part of interlayer ions in a prepolymer composed of a binder resin, a modified polyester resin, a compound that undergoes an elongation reaction or a crosslinking reaction with the prepolymer, a colorant, a release agent, and a layered inorganic mineral. Toner solution or dispersion containing modified layered inorganic mineral modified with organic ions in organic solvent is emulsified or dispersed in an aqueous medium to remove the solvent from the resulting dispersion. Any of (6) to (8) above, wherein the solution of the organic solvent or the dispersion thereof has a Casson yield value at 25 ° C. of 1 Pa to 100 Pa. An image forming method according to claim 1.
(10) The image forming method according to any one of (6) to (9), wherein an average circularity A of toner base particles of the toner is in a range of 0.94 ≦ A ≦ 0.99.
(11) A toner for an image forming method having at least an image bearing member, a charging step, an exposure step, a developing step using a developer containing toner, a transfer step, a fixing step, and a cleaning step, and produced by aqueous granulation. And having silica fine particles as an additive on the surface of the toner base, the silica being porous silica fine particles having fine pores on the surface, and having a coating area of the porous silica fine particles on the surface of the toner base. The ratio is 5 to 20%, the average primary particle size of the porous silica fine particles is 20 to 200 nm, the true specific gravity is 2.0 g / cm ³ or less, and the specific surface area is 20 to 500 m ² / g. A toner for developing an electrostatic latent image, comprising:
(12) The toner according to (11), wherein the binder resin of the toner is a polyester resin.
(13) The toner according to (11) or (12), wherein the toner contains at least one crystalline polyester resin and at least one amorphous polyester resin as a binder resin component.
(14) A prepolymer comprising a binder resin, a modified polyester resin, a compound that undergoes elongation or crosslinking reaction with the prepolymer, a colorant, a release agent, and at least part of interlayer ions in the layered inorganic mineral is modified with organic ions. Obtained by emulsifying or dispersing a solution or dispersion containing the modified layered inorganic mineral in an organic solvent in an aqueous medium to remove the solvent from the dispersion obtained by crosslinking reaction or elongation reaction The toner described in (11) or (12) above, wherein the solution of the organic solvent or the dispersion thereof has a Casson yield value at 25 ° C. of 1 Pa to 100 Pa.
(15) The toner according to any one of (11) to (14), wherein an average circularity A of the toner base particles is in a range of 0.94 ≦ A ≦ 0.99.

  According to the present invention, in a toner that is granulated in an aqueous system, the toner base surface is coated with porous silica fine particles having a constant particle diameter at a constant ratio, so that the low temperature fixability is not hindered and the toner is granulated in a high humidity environment. The toner and the image forming apparatus can be provided which achieves both the suppression of toner aggregation and the stability of charge amount and suppression of filming.

It is a schematic explanatory drawing which shows an example of the image forming apparatus used by this invention. It is a schematic explanatory drawing which shows the other example of the image forming apparatus used by this invention. It is a schematic explanatory drawing which shows the other example of the image forming apparatus used by this invention. FIG. 4 is a schematic explanatory view showing a part of the image forming apparatus shown in FIG. 3.

  As described above, the present invention is a toner prepared by aqueous granulation, and has silica fine particles as an additive on the surface of the toner base, and the silica is porous silica fine particles having fine pores on the surface. A toner having a covering area ratio of the porous silica fine particles to the toner base surface of 5 to 20%, and an average primary particle diameter of the porous silica fine particles of 20 to 200 nm, and An image forming apparatus having a developing means, a transferring means, a fixing means, and a cleaning means, and a charging process, an exposure process, and a developing process using the developer containing the toner; An image forming method including a transfer step, a fixing step, and a cleaning step.

In response to the above-mentioned problems, the porous silica fine particles added to the toner surface in a high humidity environment have a high moisture absorption capability due to the fine pores on the silica surface. It is possible to suppress an increase in adhesion between the base materials and suppress a cohesion between the toners. Furthermore, a decrease in charge amount under a high humidity environment can be suppressed, and stable image quality can be maintained over time.
Silica gel is extremely porous, as known as a desiccant for dried foods and medicines, and it absorbs moisture and releases moisture in response to humidity in the environment in which it is placed. Is less likely to be absorbed inside and exposed to the surface, or when used in a polymerized toner as an external additive in an ultrafine state, the fluidity of the polymerized toner particles is greatly reduced without impairing the physical properties of the toner. Can hold well.

The coverage of the porous silica fine particles added to the toner base surface is preferably 5 to 20%, and more preferably 7 to 15%. When the coverage is less than 5%, the water adsorption capacity by the porous silica fine particles is poor, and the charge amount reduction and toner aggregation under high humidity cannot be suppressed.
On the other hand, if it exceeds 20%, there is a concern that the low-temperature fixability may be inhibited. In addition, there is a concern that the free silica gel may promote foreign matter adhesion (hereinafter referred to as filming) that adheres to the surface of the photoconductor, or promotes wear of the photoconductor, thereby causing deterioration of image quality.

Moreover, it is preferable that the average primary particle diameter of the silica fine particle to be used is 20-200 nm, and 50-150 nm is more preferable. When the particle size is less than 20 nm, the spacer effect of the additive is hardly exhibited, and the contact area between the toner bases is wide. Therefore, even if the porous silica fine particles adsorb moisture, toner aggregation cannot be avoided. On the other hand, when the particle diameter exceeds 200 nm, the adhesion area between the base and the silica fine particles is narrow, so that the adhesive force between the silica and the base is weak, silica is likely to be released, and filming is likely to occur.
Silica fine particles preferably have a true specific gravity of 2.0 g / cm ³ or less, more preferably 1.8 g / cm ³ or less. If it exceeds 2.0 g / cm ³ , the number of pores on the silica surface will be reduced, and the number of moisture adsorption sites will be reduced.

Further, it is preferable that the BET specific surface area of the silica fine particles is in the range of 20 to 500 m ² / g, preferably more 50~450m range of ² / g. If it is less than 20 m ² / g, the pores on the silica surface are reduced, and the number of moisture adsorption sites is reduced, so that a decrease in charge amount and toner aggregation under high humidity cannot be suppressed. On the other hand, if it exceeds 500 m ² / g, there are too many moisture adsorption sites, so that the charging environment stability of the toner is poor.
Such porous silica can be produced as follows, almost in accordance with the production method described in Japanese Patent Application Laid-Open No. 2008-76421 that has already been proposed. That is, for example, commercially available (for example, silophobic 200 (surface treatment: HMDS, primary particle size: about 4 μm) of hydrophobic porous silica manufactured by Fuji Silysia Chemical Co., Ltd., manufactured by Ashizawa Finetech Co., Ltd. Using the star mill ZRS2, the silica (BET specific surface area: 20 m ² / g to 500 m) is obtained by wet grinding with zirconia beads having a diameter of 0.1 mm to 10 mm at a concentration of 5 to 30% in a solvent (eg ethanol). ² / g, primary particle diameter: 20 to 200 nm) can be adjusted.
The silica can be managed in a slurry state, dried before external addition, and crushed using a Henschel mixer 20C, and then used.
In addition, as a comparative exception additive described in this specification, RX200 (surface treatment: HMDS, BET specific surface area: 200 m ² / surface) manufactured by Nippon Aerosil Co., Ltd. manufactured by a combustion method (dry method). g, primary particle size: 12 nm) and non-porous silica having a larger specific surface area, manufactured by the combustion method (dry method), manufactured by Cabot Specialty Chemicals, Inc. As a silica TG-811F (surface treatment: HMDS, BET specific surface area: 230 m ² / g, primary particle size: 8 nm) and silica that is also not porous, the combustion method (dry method) EP-BR0401 (surface treatment: HMDS, BET specific surface) of hydrophobic silica manufactured by Cabot Specialty Chemicals, Inc. Product: 18 m ² / g, primary particle size: 200 nm).

In the toner of the present invention, the binder resin component preferably contains a binder resin precursor.
In the toner of the present invention, at least a colorant, a release agent, a crystalline polyester resin, a binder resin precursor composed of a modified polyester resin, and other binder resin components are dissolved in an organic solvent. In the oil phase obtained by dispersing, the binder resin precursor and a compound that extends or crosslinks are dissolved, and then the oil phase is dispersed in an aqueous medium in which a fine particle dispersant is present to obtain an emulsified dispersion. A toner obtained by subjecting the binder resin precursor to a crosslinking reaction and / or elongation reaction in the emulsion dispersion to remove the organic solvent is preferable.

The average circularity of the toner produced by the production method of the present invention is preferably from 0.94 to 0.99. When the average circularity is lower than 0.94, the image uniformity during development deteriorates or the electrophotographic photosensitive property is reduced. In some cases, the toner transfer efficiency from the medium to the intermediate transfer member or from the intermediate transfer member to the recording material is lowered, and uniform transfer cannot be obtained. The toner produced by the above production method is prepared by emulsification in an aqueous medium, and is particularly effective for reducing the particle size of color toners and obtaining a shape with an average circularity in the above range. It is.
The ratio (Dw / Dn) of the weight average particle diameter (Dw) to the number average particle diameter (Dn) in the toner manufactured by the above manufacturing method is preferably 1.30 or less, for example, 1.00 to 1.30. Is more preferable. When the ratio of the weight average particle diameter to the number average particle diameter (Dw / Dn) is less than 1.00, in the two-component developer, the toner is fused to the surface of the carrier during long-term agitation in the developing device, and the carrier In some cases, the chargeability of the toner tends to deteriorate and the cleaning performance deteriorates. In the case of a one-component developer, toner filming on the developing roller and toner fusion to a member such as a blade are likely to occur because the toner is thinned. Further, when Dw / Dn exceeds 1.30, it becomes difficult to obtain a high-resolution and high-quality image, and when the balance of the toner in the developer is performed, the fluctuation of the toner particle diameter increases. Sometimes.

Further, when the ratio of the weight average particle diameter to the number average particle diameter (Dw / Dn) of the toner is 1.00 to 1.30, any of storage stability, low-temperature fixability, and hot offset resistance can be obtained. Also tends to be an excellent toner. In particular, when used in a full-color copying machine, the glossiness of the image is excellent.
Even if the toner balance over a long period of time is achieved with a two-component developer, the toner particle diameter in the developer is less likely to fluctuate, and good and stable developability can be obtained even with long-term agitation in the developing device. With toner balance, the fluctuation of the toner particle size is reduced, and there is no toner filming on the developing roller or toner fusion to a member such as a blade for thinning the toner. Good and stable developability can be obtained even during long-term use (stirring) of the apparatus, and high-quality images can be obtained.

  The particle size of the carrier used together with the toner produced according to the present invention is preferably 15 to 40 μm in weight average particle size, and when it is smaller than 15 μm, the carrier adheres to the carrier being transferred together in the transfer step. On the other hand, when the particle size is larger than 40 μm, carrier adhesion hardly occurs. However, when the toner concentration is increased in order to obtain a high image density, there is a possibility that scumming is likely to occur. In addition, when the dot diameter of the latent image is small, the variation in dot reproducibility increases, and the graininess of the highlight portion may be deteriorated.

  The image forming apparatus (image forming method) of the present invention comprises an electrostatic latent image forming means (process) (charging means or charging process and exposure means or exposure process), a developing means (process), and a transfer means (process). , A fixing means (process) and a cleaning means (process), and if necessary, further a means (process) such as a charge eliminating means (process), a recycling means (process), a control means (process), etc. Also good.

The electrostatic latent image forming step is a step of forming an electrostatic latent image on the image carrier. The material, shape, structure, size and the like of the image carrier can be appropriately selected from known ones. Examples of the material include inorganic substances such as amorphous silicon and selenium, and organic substances such as polysilane and phthalopolymethine. Amorphous silicon is preferable because of its long life. Further, the shape is preferably a drum shape. The electrostatic latent image can be formed by uniformly charging the surface of the image carrier and then exposing it imagewise, and can be performed by an electrostatic latent image forming unit.
The electrostatic latent image forming unit preferably has a charger (charging unit) that uniformly charges the surface of the image carrier and an exposure unit (exposure unit) that exposes the surface of the image carrier.

Charging can be performed by applying a voltage to the surface of the image carrier using a charger.
The charger can be appropriately selected according to the purpose, but a known contact charger equipped with a conductive or semiconductive roll, brush, film, rubber blade, etc., or corona discharge such as corotron or scorotron is used. Non-contact chargers and the like.

  The exposure can be performed by exposing the surface of the image carrier using an exposure device. The exposure device can be appropriately selected according to the purpose, but various exposure devices such as a copying optical system, a rod lens array system, a laser optical system, and a liquid crystal shutter optical system can be used. It should be noted that an optical back side system in which exposure is performed from the back side of the image carrier may be adopted.

The developing means (process) is a means (process) for forming a visible image by developing the electrostatic latent image using the toner of the present invention. The visible image can be formed using a developing unit.
The developing means can be appropriately selected from known ones, and preferably has a developing unit that accommodates the toner of the present invention and can apply the toner to the electrostatic latent image in a contact or non-contact manner. The developing device may be a dry development system or a wet development system. Further, it may be a single color developer or a multicolor developer. Specifically, a stirrer for charging the developer by friction stirring and a developer having a rotatable magnet roller can be used. The developer accommodated in the developing device is a developer using the toner of the present invention, but may be a one-component developer or a two-component developer.

  In a developing device having a two-component developer, the toner and the carrier are mixed and agitated, and the toner is charged by friction at that time, and held on the surface of the rotating magnet roller in a raised state to form a magnetic brush. . Since the magnet roller is disposed in the vicinity of the image carrier, a part of the toner constituting the magnetic brush formed on the surface of the magnet roller moves to the surface of the image carrier by an electric attractive force. As a result, the electrostatic latent image is developed with toner, and a visible image is formed with toner on the surface of the image carrier.

The transfer means (process) is a means (process) for transferring a visible image to a recording medium. An intermediate transfer member is used to primarily transfer the visible image onto the intermediate transfer member, and then the visible image is transferred to the recording medium. It is preferable to perform secondary transfer on the top. At this time, the toner used is usually two or more colors, and it is preferable to use a full-color toner. For this reason, it is more preferable to have a primary transfer process in which a visible image is transferred onto an intermediate transfer member to form a composite transfer image, and a secondary transfer process in which the composite transfer image is transferred onto a recording medium.
The transfer can be performed by charging the image carrier using a transfer unit. The transfer means preferably has a primary transfer means for transferring a visible image onto an intermediate transfer member to form a composite transfer image, and a secondary transfer means for transferring the composite transfer image onto a recording medium. The intermediate transfer member can be appropriately selected from known transfer members according to the purpose, and a transfer belt or the like can be used.
The transfer means preferably has a transfer device that peels and charges the visible image formed on the image carrier to the recording medium side. There may be one transfer means or a plurality of transfer means. Specific examples of the transfer device include a corona transfer device using corona discharge, a transfer belt, a transfer roller, a pressure transfer roller, and an adhesive transfer device. The recording medium can be appropriately selected from known recording media, and recording paper or the like can be used.

  The fixing step is a step of fixing the visible image transferred to the recording medium using a fixing unit, and may be fixed each time the toner of each color is transferred to the recording medium, or each color toner is laminated. You may fix at once in the state. The fixing unit can be appropriately selected according to the purpose, but a known heating and pressing unit can be used. Examples of the heating and pressing means include a combination of a heating roller and a pressure roller, a combination of a heating roller, a pressure roller, and an endless belt. The heating in the heating and pressurizing means is usually preferably 80 ° C to 200 ° C. A known optical fixing device may be used together with or instead of the fixing unit depending on the purpose.

  The neutralization step is a step of neutralizing by applying a neutralization bias to the image carrier, and can be performed using a neutralization unit. The neutralization means can be appropriately selected from known neutralizers, and a neutralization lamp or the like can be used.

The cleaning step is a step of removing toner remaining on the image carrier, and can be performed using a cleaning unit. The cleaning means can be appropriately selected from known cleaners, and a magnetic brush cleaner, electrostatic brush cleaner, magnetic roller cleaner, blade cleaner, brush cleaner, web cleaner, or the like can be used. It is preferable to use a blade cleaner.
The recycling step is a step of recycling the toner removed in the cleaning step to the developing unit, and can be performed using the recycling unit. The recycling means can be appropriately selected according to the purpose, and a known conveying means or the like can be used.

  The control means (process) is a means (process) for controlling each means and process, and can be performed using the control means. The control means can be appropriately selected according to the purpose, and devices such as a sequencer and a computer can be used.

  The process cartridge of the present invention is used in the image forming apparatus of the present invention, and integrally supports an image carrier and at least one unit selected from a charging unit, a developing unit, and a cleaning unit to form the image of the present invention. It is detachable from the main body.

FIG. 1 shows an example of an image forming apparatus used in the present invention. The image forming apparatus (100A) includes a drum-shaped photoconductor (10) as an increasing carrier, a charging roller (20) as a charging unit, an exposure device (30) as an exposure unit, and development as a developing unit. An apparatus (40), an intermediate transfer member (50), a cleaning device (60) as a cleaning means, and a static elimination lamp (70) as a static elimination means are provided.
The intermediate transfer member (50) is an endless belt, and is stretched by three rollers (51) so as to be movable in the direction of the arrow. A part of the three rollers (51) also functions as a transfer bias roller that can apply a predetermined transfer bias (primary transfer bias) to the intermediate transfer member (50). A cleaning device (90) having a cleaning blade is disposed in the vicinity of the intermediate transfer member (50). Further, a transfer roller (80) as a transfer means capable of applying a transfer bias for transferring (secondary transfer) a visible image (toner image) to a recording paper (95) as a recording medium is opposed to the recording paper (95). Has been placed. Around the intermediate transfer member (50), there is a corona charger (58) for applying a charge to the toner image on the intermediate transfer member (50) in the rotational direction of the intermediate transfer member (50). 10) and the intermediate transfer member (50) and the contact portion between the intermediate transfer member (50) and the transfer paper (95).

  The developing device (40) includes a developing belt (41) as a developer carrying member, a black developing device (45K), a yellow developing device (45Y), and a magenta developing device (45M) provided around the developing belt (41). And a cyan developing unit (45C). The black developing device (45K) includes a developer accommodating portion (42K), a developer supply roller (43K), and a developing roller (44K), and the yellow developing device (45Y) includes a developer accommodating portion (42Y). ), A developer supply roller (43Y), and a development roller (44Y). The magenta developer (45M) includes a developer accommodating portion (42M), a developer supply roller (43M), and a development roller (44M). The cyan developing device (45C) includes a developer container (42C), a developer supply roller (43C), and a developing roller (44C). Further, the developing belt (41) is an endless belt, is stretched by a plurality of belt rollers so as to be movable in the direction of the arrow, and a part thereof is in contact with the photoreceptor (10).

  In the image forming apparatus (100A), the charging roller (20) uniformly charges the photoconductor (10), and then exposes the photoconductor (10) using the exposure device (30), thereby electrostatic latent. Form an image. Next, the electrostatic latent image formed on the photoreceptor (10) is developed by supplying a developer from the developing device (40) to form a toner image. Further, the toner image is transferred (primary transfer) onto the intermediate transfer member (50) by the voltage applied by the roller (51), and further transferred (secondary transfer) onto the recording paper (95). As a result, a transfer image is formed on the recording paper (95). The toner remaining on the photoconductor (10) is removed by a cleaning device (60) having a cleaning blade, and the charged charge on the photoconductor (10) is removed by a static elimination lamp (70).

  FIG. 2 shows another example of the image forming apparatus used in the present invention. The image forming apparatus (100B) does not include the developing belt (41), and a black developing unit (45K), a yellow developing unit (45Y), a magenta developing unit (45M), and a cyan developing unit are provided around the photoreceptor (10). Except that (45C) is arranged to face each other, it has the same configuration as that of the image forming apparatus (100A) and exhibits the same functions and effects.

FIG. 3 shows another example of the image forming apparatus used in the present invention. In FIG. 3, the same components as those in FIG. 2 are denoted by the same reference numerals.
The image forming apparatus (100C) is a tandem color image forming apparatus. The image forming apparatus (100C) includes a copying apparatus main body (150), a paper feed table (200), a scanner (300), and an automatic document feeder (400). The copying machine main body (150) is provided with an endless belt-like intermediate transfer member (50) at the center. The intermediate transfer member (50) is stretched around the support rollers (14), (15) and (16) so as to be able to move clockwise in the drawing. An intermediate transfer body cleaning device (17) for removing toner remaining on the intermediate transfer body (50) is disposed in the vicinity of the support roller (15). The intermediate transfer member (50) stretched by the support rollers (14) and (15) is opposed to image forming means (18) of four colors of yellow, cyan, magenta, and black along the conveyance direction. A tandem developing device (120) juxtaposed in parallel is arranged. An exposure device (21) is disposed in the vicinity of the tandem developing device (120). A secondary transfer device (22) is arranged on the opposite side of the intermediate transfer member (50) from the side where the tandem developing device (120) is arranged. In the secondary transfer device (22), a secondary transfer belt (24), which is an endless belt, is stretched between a pair of rollers (23), and the recording paper conveyed on the secondary transfer belt (24) is intermediate to the recording paper. The transfer bodies (50) can contact each other. A fixing device (25) is disposed in the vicinity of the secondary transfer device (22). The fixing device (25) includes a fixing belt (26) that is an endless belt, and a pressure roller (27) that is arranged to be pressed against the fixing belt (26).

In the image forming apparatus (100C), a sheet reversing device (28) for reversing the transfer paper is disposed in the vicinity of the secondary transfer device (22) and the fixing device (25). Thereby, images can be formed on both sides of the recording paper.
Next, full color image formation (color copying) using the tandem developing device (120) will be described. First, the document is set on the document table (130) of the automatic document feeder (400), or the automatic document feeder (400) is opened and the document is set on the contact glass (32) of the scanner (300). The automatic document feeder (400) is closed.
When a start switch (not shown) is pressed, when the document is set on the automatic document feeder (400), the document is conveyed on the contact glass (32) and then on the contact glass (32). When is set, the scanner (300) is immediately driven, and the first traveling body (33) and the second traveling body (34) travel. At this time, the reflected light from the original surface of the light irradiated by the first traveling body (33) is reflected by the mirror of the second traveling body (34) and passes through the imaging lens (35) to the reading sensor (36). Received light. As a result, a color original (color image) is read and used as image information for each color of black, yellow, magenta, and cyan. The image information of each color is transmitted to the image forming means (18) for each color in the tandem developing device (120), and a toner image for each color is formed.
The toner image on the black photoconductor (10K), the toner image on the yellow photoconductor (10Y), the toner image on the magenta photoconductor (10M), and the toner image on the cyan photoconductor (10C) are intermediate. Transfer (primary transfer) is sequentially performed on the transfer body (50). Then, the toner images of the respective colors are superimposed on the intermediate transfer member (50) to form a composite color image (color transfer image).

  As shown in FIG. 4, each color image forming means (18) in the tandem developing device (120) includes a photoreceptor (10) and a charger (59) for uniformly charging the photoreceptor (10). And an exposure device (21) that forms an electrostatic latent image on the photoconductor (10) by exposing the photoconductor (10) based on the image information of each color (symbol (L) in the figure), By developing the electrostatic latent image using the toner of each color, a developing device (61) for forming the toner image of each color on the photoreceptor (10), and the toner image of each color on the intermediate transfer member (50) A transfer charger (62) for transferring, a photoconductor cleaning device (63), and a static eliminator (64) are provided.

On the other hand, in the paper feed table (200), one of the paper feed rollers (142a) is selectively rotated to feed the recording paper from one of the paper feed cassettes (144) provided in multiple stages in the paper bank (143). The sheet is separated one by one by the separation roller (145a), sent to the sheet feeding path (146), conveyed by the conveying roller (147) and guided to the sheet feeding path (148) in the copying machine main body (150), and the registration roller Stop at (49). Alternatively, the recording paper on the manual feed tray (52) is fed out by rotating the paper feed roller (142b), separated one by one by the separation roller (145b), and put into the manual paper feed path (53). 49) and stop. The registration roller (49) is generally used while being grounded, but may be used in a state where a bias is applied to remove paper dust from the sheet.
Then, the registration roller (49) is rotated in time with the color transfer image formed on the intermediate transfer member (50), and the recording paper is interposed between the intermediate transfer member (50) and the secondary transfer device (22). , A color transfer image is formed on the recording paper. The toner remaining on the intermediate transfer body (50) after the transfer is cleaned by the intermediate transfer body cleaning device (17).
The recording paper on which the color transfer image is formed is conveyed to the fixing device (25) by the secondary transfer device (22), and the color transfer image is fixed on the recording paper by heat and pressure. Thereafter, the recording paper is switched by the switching claw (55), discharged by the discharge roller (56), and stacked on the discharge tray (57). Alternatively, the sheet is switched by the switching claw (55), reversed by the sheet reversing device (28) and led to the transfer position again, and after the image is formed on the back surface, the sheet is discharged by the discharge roller (56) and discharged by the discharge tray (57). ) Is stacked on top.
The process cartridge of the present invention is used in the image forming apparatus of the present invention, and integrally supports an image carrier and at least one means selected from a charging device, a developing device, and a cleaning device, and is attached to the image forming apparatus main body. It is detachable.

[Toner characteristics measurement method]
<Casson yield measurement method>
The Casson yield value can be measured using a high shear viscometer or the like.
The measurement conditions are as follows.
Device: AR2000 (TA Instruments)
Shear stress: 120 Pa / 5 min Geometry: 40 mm steel plate Geometry gap: 1 mm
Analysis software: TA DATA ANALYSIS (TA Instruments)

<Weight average particle diameter (Dw), volume average particle diameter (Dv), and number average particle diameter (Dn)>
The weight average particle diameter (Dw), volume average particle diameter (Dv), and number average particle diameter (Dn) of the toner were measured using a particle size measuring device (“Multisizer III”, manufactured by Beckman Coulter, Inc.) with an aperture diameter of 100 μm. It measured and analyzed with the analysis software (Beckman Coulter Multisizer 3 Version3.51). Specifically, 0.5 ml of 10 wt% surfactant (alkylbenzene sulfonate Neogen SC-A; Daiichi Kogyo Seiyaku) was added to a glass 100 ml beaker, 0.5 g of each toner was added, and the mixture was stirred with a micropartel. Subsequently, 80 ml of ion-exchanged water was added. The obtained dispersion was subjected to a dispersion treatment for 10 minutes with an ultrasonic disperser (W-113MK-II, manufactured by Honda Electronics Co., Ltd.). The dispersion was measured using the Multisizer III and Isoton III (manufactured by Beckman Coulter) as the measurement solution. In the measurement, the toner sample dispersion was dropped so that the concentration indicated by the apparatus was 8 ± 2%. In this measurement method, it is important that the concentration is 8 ± 2% from the viewpoint of the reproducibility of the particle size. Within this concentration range, no error occurs in the particle size.

<Average circularity>
The average circularity of the toner is defined by the average circularity SR = (peripheral length of a circle having the same area as the particle projection area / perimeter length of the particle projection image) × 100%. Measurement was performed using a flow type particle image analyzer (“FPIA-2100”; manufactured by Sysmex Corporation), and analysis was performed using analysis software (FPIA-2100 Data Processing Program for FPIA version 00-10). Specifically, 0.1 to 0.5 ml of 10 wt% surfactant (alkylbenzene sulfonate Neogen SC-A; Daiichi Kogyo Seiyaku) is added to a glass 100 ml beaker, and each toner 0.1 to 0 is added. 0.5 g was added and stirred with a microspatel, and then 80 ml of ion-exchanged water was added. The obtained dispersion was subjected to a dispersion treatment for 3 minutes with an ultrasonic disperser (manufactured by Honda Electronics Co., Ltd.). The shape and distribution of the toner were measured using the FPIA-2100 until the density of the dispersion was 5000 to 15000 / μl. In this measurement method, it is important that the concentration of the dispersion liquid is 5000 to 15000 / μl from the viewpoint of measurement reproducibility of the average circularity. In order to obtain the dispersion concentration, it is necessary to change the conditions of the dispersion, that is, the amount of surfactant to be added and the amount of toner. The amount of the surfactant varies depending on the hydrophobicity of the toner as in the toner particle size measurement described above. If a large amount is added, noise due to bubbles is generated. It will be enough. Further, the toner addition amount differs from the particle size, and it is necessary to decrease the small particle size and increase the large particle size. When the toner particle size is 3 to 7 μm, the toner amount is 0.1 to 0. By adding 0.5 g, the dispersion concentration can be adjusted to 5000 to 15000 / μl.

<Ratio of covering area>
The toner was adhered to the observation substrate for an electron microscope, the observation substrate to which the toner was adhered was coated with gold, and the surface of the toner was observed with an electron microscope (Hitachi, Ltd., scanning electron microscope S-4500).
An image obtained by magnifying the toner surface by 30,000 times is taken into a personal computer, and the area of the porous silica fine particles is measured by using an image processing software (Image-Pro Plus manufactured by Media Cybernetics). The percentage was calculated and determined.

[Method for measuring carrier characteristics]
<Weight average particle size>
The weight average particle diameter Dw of the carrier is calculated based on the particle diameter distribution (relationship between the number frequency and the particle diameter) of the particles measured on the basis of the number. The weight average particle diameter Dw in this case is represented by the formula (1).
Dw = {1 / Σ (nD ³ )} × {Σ (nD ⁴ )} (1)
In formula (1), D represents the representative particle size (μm) of the particles present in each channel, and n represents the total number of particles present in each channel. The channel indicates a length for equally dividing the particle size range in the particle size distribution diagram, and 2 μm is adopted in the present invention. In addition, as the representative particle size of the particles present in each channel, the lower limit value of the particle size of the particles stored in each channel was adopted.

Further, the number average particle diameter Dp of the carrier and the core material particles of the carrier is calculated based on the particle diameter distribution of the particles measured on the basis of the number. The number average particle diameter Dp in this case is represented by the formula (2).
Dp = (1 / ΣN) × (ΣnD) (2)
In formula (2), N represents the total number of particles measured, n represents the total number of particles present in each channel, and D represents the lower limit of the particle size of the particles stored in each channel (2 μm). Show.
In the present invention, a microtrack particle size analyzer model HRA9320-X100 (manufactured by Honeywell) can be used as a particle size analyzer for measuring the particle size distribution. The measurement conditions are as follows.
[1] Particle size range: 8 to 100 μm
[2] Channel length (channel width): 2 μm
[3] Number of channels: 46
[4] Refractive index: 2.42

Hereinafter, an example of a method for producing the toner of the present invention will be specifically described.
The present invention is not limited to the toner production method exemplified here.
In emulsification or dispersion, it is preferable to use a dispersant from the viewpoint of stabilizing the oil droplets and sharpening the particle size distribution while obtaining a desired shape, if necessary. There is no restriction | limiting in particular as a dispersing agent, According to the objective, it can select suitably, For example, surfactant, a slightly water-soluble inorganic compound dispersing agent, a polymeric protective colloid, etc. can be used. These may be used individually by 1 type and may use 2 or more types together. Among these, surfactants are preferable. Further, after removing the organic solvent, silica fine particles are externally added in the step of externally adding and mixing the additive. At this time, as the additive to be added, one kind of silica fine particles may be used alone, or two or more kinds of inorganic fine particles may be used in combination.

[Raw materials used in the production of the toner of the present invention]
(Anionic surfactant)
Examples of the anionic surfactant used in the production method of the present invention include alkylbenzene sulfonate, α-olefin sulfonate, phosphate ester, etc., and an anionic surfactant having a fluoroalkyl group is preferable. It is mentioned in. Examples of the anionic surfactant having a fluoroalkyl group include a fluoroalkylcarboxylic acid having 2 to 10 carbon atoms or a metal salt thereof, disodium perfluorooctanesulfonylglutamate, 3- [ω-fluoroalkyl (having 6 to 6 carbon atoms). 11) Sodium oxy] -1-alkyl (C3-4) sulfonate, sodium 3- [ω-fluoroalkanoyl (C6-8) -N-ethylamino] -1-propanesulfonate, fluoroalkyl ( Carbon number 11-20) carboxylic acid or metal salt thereof, perfluoroalkyl carboxylic acid (carbon number 7-13) or metal salt thereof, perfluoroalkyl (carbon number 4-12) sulfonic acid or metal salt thereof, perfluorooctane Sulfonic acid diethanolamide, N-propyl-N- (2-hydroxyethyl) par -Fluorooctanesulfonamide, perfluoroalkyl (carbon number 6-10) sulfonamidopropyltrimethylammonium salt, perfluoroalkyl (carbon number 6-10) -N-ethylsulfonylglycine salt, monoperfluoroalkyl (carbon number 6-6) 16) Ethyl phosphate and the like.
Examples of commercially available anionic surfactants having a fluoroalkyl group include Surflon S-111, S-112, and S-113 (Asahi Glass Co., Ltd.); Fluorard FC-93, FC-95, FC-98, FC -129 (manufactured by Sumitomo 3M); Unidyne DS-101, DS-102 (manufactured by Daikin Industries); Megafac F-110, F-120, F-113, F-191, F-812, F-833 ( Dainippon Ink, Inc.); Xtop EF-102, 103, 104, 105, 112, 123A, 123B, 306A, 501, 201, 204 (manufactured by Tochem Products); Etc.). (Binder Resin: For convenience of explanation, the binder resin to the magnetic material described below may be referred to as toner material.)

The binder resin used in the method for producing the toner of the present invention is not particularly limited, and preferably contains at least two kinds of resins, such as polyester resins, silicone resins, styrene / acryl resins, styrene resins, acrylic resins, Known binder resins such as epoxy resins, diene resins, phenol resins, terpene resins, coumarin resins, amideimide resins, butyral resins, urethane resins, ethylene / vinyl acetate resins can be used.
Among them, the resin phase for the toner production method of the present invention includes a polyester resin (modified) that has sufficient flexibility even when the molecular weight is lowered because it can sharply melt during fixing and smooth the image surface. (Including polyester resins), and other resins may be used in combination with polyester resins.
The polyester resin used in the present invention is one or two or more polyols represented by the following general formula (1):
A- (OH) m (1)
[Wherein, A represents an alkyl group having 1 to 20 carbon atoms, an alkylene group, or an aromatic group or heterocyclic aromatic group which may have a substituent. m represents an integer of 2 to 4. ]
One or two or more polycarboxylic acids represented by the following general formula (2) are polyesterified.
B- (COOH) n (2)
[Wherein, B represents an alkyl group having 1 to 20 carbon atoms, an alkylene group, or an aromatic group or heterocyclic aromatic group which may have a substituent. n represents an integer of 2 to 4. ]

  Specific polyols represented by the general formula (1) include ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, neopentyl glycol, 1,4-butenediol, 1,5-pentanediol, 1,6-hexanediol, 1,4-cyclohexanedimethanol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, sorbitol, 1,2, 3,6-hexanetetrol, 1,4-sorbitan, pentaerythritol, dipentaerythritol, tripentaerythritol, 1,2,4-butanetriol, 1,2,5-pentanetriol, glycerol, 2-methyl Propanetriol, 2-methyl-1,2,4-butanetriol, trimethylolethane, trimethylolpropane, 1,3,5-trihydroxymethylbenzene, bisphenol A, bisphenol A ethylene oxide adduct, bisphenol A propylene oxide addition Products, hydrogenated bisphenol A, hydrogenated bisphenol A ethylene oxide adduct, hydrogenated bisphenol A propylene oxide adduct, and the like.

  Specific polycarboxylic acids represented by the general formula (2) include maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, phthalic acid, isophthalic acid, terephthalic acid, succinic acid, adipic acid, and sebacic acid. Azelaic acid, malonic acid, n-dodecenyl succinic acid, isooctyl succinic acid, isododecenyl succinic acid, n-dodecyl succinic acid, isododecyl succinic acid, n-octenyl succinic acid, n-octyl succinic acid, isooctenyl succinic acid, Isooctyl succinic acid, 1,2,4-benzenetricarboxylic acid, 2,5,7-naphthalenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, 1,2,4-butanetricarboxylic acid, 1,2,5 -Hexanetricarboxylic acid, 1,3-dicarboxyl-2-methyl-2-methylenecarboxyprop 1,2,4-cyclohexanetricarboxylic acid, tetra (methylenecarboxyl) methane, 1,2,7,8-octanetetracarboxylic acid, pyromellitic acid, emporic trimer acid, cyclohexanedicarboxylic acid, cyclohexenedicarboxylic acid, Examples include butanetetracarboxylic acid, diphenylsulfonetetracarboxylic acid, and ethylene glycol bis (trimellitic acid).

(Active hydrogen group-containing compound, polymer capable of reacting with active hydrogen group-containing compound)
Among the polyester resins in the present invention, the modified polyester resin can be obtained by reacting an active hydrogen group-containing compound and a polymer capable of reacting with the active hydrogen group-containing compound.
Examples of the active hydrogen group-containing compound include an amino group-containing compound, a hydroxy group-containing compound, water, a mercapto group-containing compound, a polycarboxyl compound, a mono- or diphosphate ester, and particularly preferably an amino group-containing material or a polyol material. be able to. These may be low molecular weight compounds, oligomers, polymers such as polyester oligomers and prepolymers containing unreacted hydroxy groups that have been polyesterified, and polyester polymers having a relatively low molecular weight (for example, a molecular weight of 1000 to 20000). .
The polymer that can react with the active hydrogen group-containing compound (hereinafter referred to as “prepolymer”) is not particularly limited as long as it has at least a site that can react with the active hydrogen group-containing compound. For example, a polyol resin, a polyacrylic resin, a polyester resin, an epoxy resin, a derivative resin thereof, or the like can be used.
Among these, a polyester resin is particularly preferable in terms of high fluidity and transparency during melting.
In addition, these may be used individually by 1 type and may use 2 or more types together.
The site capable of reacting with the active hydrogen group-containing compound in the prepolymer is not particularly limited and may be appropriately selected from known substituents. For example, an isocyanate group, an epoxy group, a carboxylic acid, an acid chloride Group, and the like. These may be contained singly or in combination of two or more. Among these, an isocyanate group is particularly preferable. Among prepolymers, it is easy to adjust the molecular weight of the polymer component, ensuring oil-free low-temperature fixing characteristics for dry toners, especially good release and fixing properties even without a release oil coating mechanism for the heating medium for fixing. In view of the capability, a urea bond-forming group-containing polyester resin (RMPE) is particularly preferable.
As a urea bond production | generation group, an isocyanate group etc. are mentioned, for example. When the urea bond generating group in the urea bond generating group-containing polyester resin (RMPE) is the isocyanate group, the polyester resin (RMPE) is particularly preferably an isocyanate group-containing polyester prepolymer (A). The isocyanate group-containing polyester prepolymer (A) is not particularly limited and may be appropriately selected depending on the intended purpose. For example, it is a polycondensate of a polyol (PO) and a polycarboxylic acid (PC), and Examples include those obtained by reacting an active hydrogen group-containing polyester resin with polyisocyanate (PIC). There is no restriction | limiting in particular as a polyol (PO), According to the objective, it can select suitably, For example, diol (DIO), trihydric or more polyol (TO), diol (DIO), and trihydric or more polyol ( TO) and the like. These may be used individually by 1 type and may use 2 or more types together. Among these, diol (DIO) alone or a mixture of diol (DIO) and a small amount of a trivalent or higher polyol (TO) is preferable. Examples of the diol (DIO) include alkylene glycol, alkylene ether glycol, alicyclic diol, alkylene oxide adduct of alicyclic diol, bisphenol, alkylene oxide adduct of bisphenol, and the like.
As the alkylene glycol, those having 2 to 12 carbon atoms are preferable, and examples thereof include ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,6-hexanediol, and the like. It is done. Examples of the alkylene ether glycol include diethylene glycol, triethylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol, and polytetramethylene ether glycol. Examples of the alicyclic diol include 1,4-cyclohexanedimethanol and hydrogenated bisphenol A. Examples of the alkylene oxide adduct of alicyclic diol include those obtained by adding an alkylene oxide such as ethylene oxide, propylene oxide, butylene oxide to the alicyclic diol. Examples of bisphenols include bisphenol A, bisphenol F, and bisphenol S. Examples of the alkylene oxide adduct of bisphenols include those obtained by adding an alkylene oxide such as ethylene oxide, propylene oxide, and butylene oxide to bisphenols. Among these, alkylene glycols having 2 to 12 carbon atoms, alkylene oxide adducts of bisphenols and the like are preferable, and alkylene oxide adducts of bisphenols, alkylene oxide adducts of bisphenols and alkylene glycols having 2 to 12 carbon atoms. Mixtures are particularly preferred.
The trivalent or higher polyol (TO) is preferably 3 to 8 or higher, for example, a trihydric or higher polyhydric aliphatic alcohol, a trihydric or higher polyphenol, an alkylene of a trihydric or higher polyphenol. And oxide adducts. Examples of the trivalent or higher polyhydric aliphatic alcohol include glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, sorbitol, and the like. Examples of the trihydric or higher polyphenols include trisphenol bodies (such as Trisphenol PA manufactured by Honshu Chemical Industry Co., Ltd.), phenol novolacs, cresol novolacs, and the like. Examples of the alkylene oxide adduct of trihydric or higher polyphenols include those obtained by adding an alkylene oxide such as ethylene oxide, propylene oxide, or butylene oxide to trihydric or higher polyphenols.
The mixing mass ratio (DIO: TO) of the diol (DIO) and the trihydric or higher polyol (TO) in the mixture of the diol (DIO) and the trihydric or higher polyol (TO) is 100: 0.01 to 10 Is preferable, and 100: 0.01-1 is more preferable.
There is no restriction | limiting in particular as polycarboxylic acid (PC), Although it can select suitably according to the objective, For example, dicarboxylic acid (DIC), trivalent or more polycarboxylic acid (TC), dicarboxylic acid (DIC) And a mixture of trivalent or higher valent polycarboxylic acids. These may be used individually by 1 type and may use 2 or more types together. Among these, dicarboxylic acid (DIC) alone or a mixture of dicarboxylic acid (DIC) and a small amount of trivalent or higher polycarboxylic acid (TC) is preferable.
Examples of the dicarboxylic acid (DIC) include alkylene dicarboxylic acid, alkenylene dicarboxylic acid, aromatic dicarboxylic acid, and the like. Examples of the alkylene dicarboxylic acid include succinic acid, adipic acid, and sebacic acid. Moreover, as alkenylene dicarboxylic acid, a C4-C20 thing is preferable, For example, a maleic acid, a fumaric acid, etc. are mentioned. Moreover, as aromatic dicarboxylic acid, a C8-C20 thing is preferable, for example, a phthalic acid, isophthalic acid, a terephthalic acid, naphthalene dicarboxylic acid etc. are mentioned. Among these, alkenylene dicarboxylic acid having 4 to 20 carbon atoms and aromatic dicarboxylic acid having 8 to 20 carbon atoms are preferable.
The trivalent or higher polycarboxylic acid (TC) is preferably 3 to 8 or higher, and examples thereof include aromatic polycarboxylic acids. Moreover, as an aromatic polycarboxylic acid, a C9-C20 thing is preferable, for example, trimellitic acid, pyromellitic acid, etc. are mentioned.
The polycarboxylic acid (PC) is any one selected from dicarboxylic acid (DIC), trivalent or higher polycarboxylic acid (TC), and a mixture of dicarboxylic acid (DIC) and trivalent or higher polycarboxylic acid. These acid anhydrides or lower alkyl ester compounds can also be used. Examples of the lower alkyl ester include methyl ester, ethyl ester, isopropyl ester and the like.
As a mixing mass ratio (DIC: TC) of dicarboxylic acid (DIC) and trivalent or higher polycarboxylic acid (TC) in a mixture of dicarboxylic acid (DIC) and trivalent or higher polycarboxylic acid (TC), There is no restriction | limiting, According to the objective, it can select suitably, For example, 100: 0.01-10 are preferable and 100: 0.01-1 are more preferable.
The mixing ratio for the polycondensation reaction between the polyol (PO) and the polycarboxylic acid (PC) is not particularly limited and may be appropriately selected depending on the intended purpose. For example, the hydroxyl group in the polyol (PO) [ OH] and the equivalent ratio ([OH] / [COOH]) of the carboxyl group [COOH] in the polycarboxylic acid (PC) are usually preferably 2/1 to 1/1, and 1.5 / The ratio is more preferably 1-1 / 1, and particularly preferably 1.3 / 1-1.02 / 1.
There is no restriction | limiting in particular as content in the isocyanate group containing polyester prepolymer (A) of a polyol (PO), Although it can select suitably according to the objective, 0.5-40 mass% is preferable, for example. -30 mass% is more preferable, and 2-20 mass% is especially preferable. This is because if the content is less than 0.5% by mass, the hot offset resistance deteriorates, and it may be difficult to achieve both the heat-resistant storage stability and the low-temperature fixability of the toner. This is because the low temperature fixability may be deteriorated if the temperature exceeds.
There is no restriction | limiting in particular as polyisocyanate (PIC), Although it can select suitably according to the objective, For example, aliphatic polyisocyanate, alicyclic polyisocyanate, aromatic diisocyanate, araliphatic diisocyanate, isocyanurates And those blocked with phenol derivatives, oximes, caprolactams, and the like.
Examples of the aliphatic polyisocyanate include tetramethylene diisocyanate, hexamethylene diisocyanate, 2,6-diisocyanatomethylcaproate, octamethylene diisocyanate, decamethylene diisocyanate, dodecamethylene diisocyanate, tetradecamethylene diisocyanate, trimethylhexane diisocyanate, tetra And methyl hexane diisocyanate. Examples of the alicyclic polyisocyanate include isophorone diisocyanate and cyclohexylmethane diisocyanate. Examples of the aromatic diisocyanate include tolylene diisocyanate, diphenylmethane diisocyanate, 1,5-naphthylene diisocyanate, diphenylene-4,4′-diisocyanate, 4,4′-diisocyanato-3,3′-dimethyldiphenyl, 3 -Methyldiphenylmethane-4,4'-diisocyanate, diphenyl ether-4,4'-diisocyanate and the like. Examples of the araliphatic diisocyanate include α, α, α ′, α′-tetramethylxylylene diisocyanate. Examples of isocyanurates include tris-isocyanatoalkyl-isocyanurate and triisocyanatocycloalkyl-isocyanurate. These may be used alone or in combination of two or more.
As a mixing ratio when the polyisocyanate (PIC) is reacted with an active hydrogen group-containing polyester resin (for example, a hydroxyl group-containing polyester resin), an isocyanate group [NCO] in the polyisocyanate (PIC) and a hydroxyl group in the hydroxyl group-containing polyester resin [ The mixing equivalent ratio with [OH] ([NCO] / [OH]) is usually preferably 5/1 to 1/1, more preferably 4/1 to 1.2 / 1. It is particularly preferably 1 to 1.5 / 1. This is because if the isocyanate group [NCO] exceeds 5, low-temperature fixability may deteriorate, and if it is less than 1, offset resistance may deteriorate.
There is no restriction | limiting in particular as content in the isocyanate group containing polyester prepolymer (A) of polyisocyanate (PIC), Although it can select suitably according to the objective, For example, 0.5-40 mass% is preferable, 1-30 mass% is more preferable, and 2-20 mass% is further more preferable. This is because, when the content is less than 0.5% by mass, the hot offset resistance is deteriorated, and it may be difficult to achieve both heat-resistant storage stability and low-temperature fixability, and exceeds 40% by mass. This is because the low-temperature fixability deteriorates.
As an average number of the isocyanate groups contained per molecule of the isocyanate group-containing polyester prepolymer (A), 1 or more is preferable, 1.2 to 5 is more preferable, and 1.5 to 4 is more preferable. This is because if the average number of isocyanate groups is less than 1, the molecular weight of the polyester resin (RMPE) modified with urea bond-forming groups is lowered, and the hot offset resistance is deteriorated.
The weight average molecular weight (Mw) of the polymer capable of reacting with the active hydrogen group-containing compound is preferably 3,000 to 40,000 in terms of molecular weight distribution by GPC (gel permeation chromatography) soluble in tetrahydrofuran (THF). 4,000 to 30,000 are more preferable. This is because when the weight average molecular weight (Mw) is less than 3,000, the heat resistant storage stability may be deteriorated, and when it exceeds 40,000, the low temperature fixability may be deteriorated.
The molecular weight distribution can be measured by gel permeation chromatography (GPC), for example, as follows. That is, first, the column was stabilized in a 40 ° C. heat chamber, and at this temperature, tetrahydrofuran (THF) was flowed as a column solvent at a flow rate of 1 ml / min to adjust the sample concentration to 0.05 to 0.6% by mass. Measurement is performed by injecting 50 to 200 μl of a tetrahydrofuran sample solution of the resin. In measuring the molecular weight of the sample, the molecular weight distribution of the sample is calculated from the relationship between the logarithmic value of the calibration curve prepared by several monodisperse polystyrene standard samples and the number of counts. As a standard polystyrene sample for preparing a calibration curve, Pressure Chemical Co. Or Toyo Soda Kogyo Co., Ltd. having a molecular weight of ^{6 × 10 2, 2.1 × 10} 2, 4 × 10 2, 1.75 × 10 4, 1.1 × 10 5, 3.9 × 10 5, 8.6 It is preferable to use those of × 10 ⁵ , 2 × 10 ⁶ , and 4.48 × 10 ⁶ and use at least about 10 standard polystyrene samples. An RI (refractive index) detector can be used as the detector.

(Other ingredients)
The other components are not particularly limited and may be appropriately selected depending on the purpose. For example, colorants, mold release agents, charge control agents, inorganic fine particles, fluidity improvers, cleaning improvers, magnetic properties, and the like. Materials, metal soaps, and the like.

(Coloring agent)
The colorant for the toner used in the present invention is not particularly limited and can be appropriately selected from known dyes and pigments according to the purpose. For example, carbon black, nigrosine dye, iron black, naphthol yellow S, Hansa Yellow (10G, 5G, G), Cadmium Yellow, Yellow Iron Oxide, Ocher, Yellow Lead, Titanium Yellow, Polyazo Yellow, Oil Yellow, Hansa Yellow (GR, A, RN, R), Pigment Yellow L, Benzidine Yellow (G, GR), Permanent Yellow (NCG), Vulcan Fast Yellow (5G, R), Tartrazine Lake, Quinoline Yellow Lake, Anthrazan Yellow BGL, Isoindolinone Yellow, Bengala, Red Sand, Red Zhu , Cadmium Red, Cadmium Mercury Red, Antimon Zhu, Par Nent Red 4R, Para Red, Faise Red, Parachlor Ortho Nitroaniline Red, Resol Fast Scarlet G, Brilliant Fast Scarlet, Brilliant Carnmin BS, Permanent Red (F2R, F4R, FRL, FRLL, F4RH), Fast Scarlet VD, Belkan Fast Rubin B, Brilliant Scarlet G, Risor Rubin GX, Permanent Red F5R, Brilliant Carmine 6B, Pigment Scarlet 3B, Bordeaux 5B, Toluidine Maroon, Permanent Bordeaux F2K, Helio Bordeaux BL, Bordeaux 10B, Bon Maroon Light, Bon Maroon Medium, Eosin Rake, Rhodamine Lake B, Rhodamine Lake Y, Alizarin Lake, Thioindigo Red B, Chi Indigo Maroon, Oil Red, Quinacridone Red, Pyrazolone Red, Polyazo Red, Chrome Vermilion, Benzidine Orange, Perinone Orange, Oil Orange, Cobalt Blue, Cerulean Blue, Alkaline Blue Lake, Peacock Blue Lake, Victoria Blue Lake, Metal-free Phthalocyanine Blue Phthalocyanine blue, fast sky blue, indanthrene blue (RS, BC), indigo, ultramarine, bitumen, anthraquinone blue, fast violet B, methyl violet lake, cobalt purple, manganese purple, dioxane violet, anthraquinone violet, chrome green, Zinc green, chromium oxide, pyridian, emerald green, pigment green B, naphthol green B, green Examples include lean gold, acid green lake, malachite green lake, phthalocyanine green, anthraquinone green, titanium oxide, zinc white, and lithopone. These may be used individually by 1 type and may use 2 or more types together.
There is no restriction | limiting in particular in content in the toner of a coloring agent, Although it can select suitably according to the objective, 1-15 mass% is preferable and 3-10 mass% is more preferable. When the content of the colorant is less than 1% by mass, a reduction in the coloring power of the toner is observed. When the content exceeds 15% by mass, poor pigment dispersion occurs in the toner, resulting in a reduction in the coloring power, and the toner. The electrical characteristics may be degraded.

The colorant may be used as a master batch combined with a resin. The resin is not particularly limited and may be appropriately selected from known ones according to the purpose. For example, polyester, styrene or a substituted polymer thereof, styrene copolymer, polymethyl methacrylate, polybutyl Methacrylate, polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, epoxy resin, epoxy polyol resin, polyurethane, polyamide, polyvinyl butyral, polyacrylic acid resin, rosin, modified rosin, terpene resin, aliphatic hydrocarbon resin, alicyclic Examples thereof include hydrocarbon resins, aromatic petroleum resins, chlorinated paraffins, and paraffin waxes. These may be used individually by 1 type and may use 2 or more types together.
Examples of the polymer of styrene or a substituted product thereof include polyester resin, polystyrene, poly p-chlorostyrene, polyvinyl toluene, and the like. Examples of the styrene copolymer include a styrene-p-chlorostyrene copolymer, a styrene-propylene copolymer, a styrene-vinyltoluene copolymer, a styrene-vinylnaphthalene copolymer, and a styrene-methyl acrylate copolymer. Polymer, styrene-ethyl acrylate copolymer, styrene-butyl acrylate copolymer, styrene-octyl acrylate copolymer, styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene- Butyl methacrylate copolymer, styrene-α-chloromethyl methacrylate copolymer, styrene-acrylonitrile copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene N-acrylonitrile-indene copolymer, Styrene - maleic acid copolymer, styrene - maleic acid ester copolymer, and the like.
The master batch can be produced by mixing or kneading a resin for a master batch and a colorant with a high shear force. At this time, it is preferable to add an organic solvent in order to enhance the interaction between the colorant and the resin. Also, the so-called flushing method is preferable in that the wet cake of the colorant can be used as it is, and there is no need to dry it. This flushing method is a method in which an aqueous paste containing water of a colorant is mixed or kneaded together with a resin and an organic solvent, and the colorant is transferred to the resin side to remove moisture and organic solvent components. For the mixing or kneading, for example, a high shear dispersion device such as a three-roll mill is preferably used. The colorant can be arbitrarily contained in both the first resin phase and the second resin phase by utilizing the difference in affinity for the two resins. It is well known that the colorant deteriorates the charging performance of the toner when present on the toner surface. Therefore, the charging performance (environmental stability, charge retention ability, charge amount, etc.) of the toner can be improved by selectively incorporating a colorant into the first resin phase present in the inner layer.

(Release agent)
There is no restriction | limiting in particular as a mold release agent, Although it can select suitably according to the objective, The low melting-point mold release agent whose melting | fusing point is 50-120 degreeC is preferable. The low melting point release agent, when dispersed with the resin, effectively acts as a release agent between the fixing roller and the toner interface, thereby preventing oilless (a release agent such as oil on the fixing roller). Even if it is not applied), the hot offset property is good.
Preferable examples of the release agent include waxes and waxes. Examples of waxes and waxes include plant waxes such as carnauba wax, cotton wax, wood wax, and rice wax; animal waxes such as beeswax and lanolin; mineral waxes such as ozokerite and cercin; paraffin and microcrystalline And natural waxes such as petroleum waxes such as Petrolatum; In addition to these natural waxes, synthetic hydrocarbon waxes such as Fischer-Tropsch wax and polyethylene wax; synthetic waxes such as esters, ketones and ethers; Furthermore, fatty acid amides such as 12-hydroxystearic acid amide, stearic acid amide, phthalic anhydride imide, chlorinated hydrocarbons; poly-n-stearyl methacrylate, poly-n-lauryl which are low molecular weight crystalline polymer resins A homopolymer or copolymer of a polyacrylate such as methacrylate (for example, a copolymer of n-stearyl acrylate-ethyl methacrylate, etc.); a crystalline polymer having a long alkyl group in the side chain, or the like may be used. These may be used alone or in combination of two or more.
There is no restriction | limiting in particular as melting | fusing point of a mold release agent, Although it can select suitably according to the objective, 50-120 degreeC is preferable and 60-90 degreeC is more preferable. If the melting point is less than 50 ° C., the wax may adversely affect the heat-resistant storage stability, and if it exceeds 120 ° C., a cold offset may easily occur during fixing at a low temperature. The melt viscosity of the release agent is preferably 5 to 1000 cps, more preferably 10 to 100 cps, as a measured value at a temperature 20 ° C. higher than the melting point of the wax. When the melt viscosity is less than 5 cps, the releasability may be lowered, and when it exceeds 1,000 cps, the effect of improving hot offset resistance and low-temperature fixability may not be obtained. There is no restriction | limiting in particular as content in the said toner of a mold release agent, Although it can select suitably according to the objective, 0-40 mass% is preferable and 3-30 mass% is more preferable. When the content exceeds 40% by mass, the fluidity of the toner may be deteriorated.
The release agent can be arbitrarily contained in both the first resin phase and the second resin phase by utilizing the difference in affinity for the two resins. By selectively including in the second resin phase present in the outer layer of the toner, the release of the release agent can occur sufficiently even in a short heating time during fixing, so that sufficient release properties can be obtained. Further, by selectively including the release agent in the first resin phase present in the inner layer, the spent of the release agent to other members such as a photoreceptor and a carrier can be suppressed. In the present invention, the arrangement of the release agent may be designed relatively freely, and any arrangement can be taken according to each image forming process.

(Charge control agent)
The charge control agent is not particularly limited and may be appropriately selected from known materials according to the purpose. For example, a nigrosine dye, a triphenylmethane dye, a chromium-containing metal complex dye, a molybdate chelate pigment, Rhodamine dyes, alkoxy amines, quaternary ammonium salts (including fluorine-modified quaternary ammonium salts), alkylamides, phosphorus alone or compounds thereof, tungsten alone or compounds thereof, fluorine activators, metal salts of salicylic acid, And metal salts of salicylic acid derivatives. These may be used individually by 1 type and may use 2 or more types together.
A commercially available product may be used as the charge control agent. Examples of the commercially available product include bontron 03 of a nigrosine dye, bontron P-51 of a quaternary ammonium salt, bontron S-34 of a metal-containing azo dye, O-naphthoic acid metal complex E-82, salicylic acid metal complex E-84, phenol condensate E-89 (above, manufactured by Orient Chemical Industries), quaternary ammonium salt molybdenum complex TP-302, TP-415 (above, manufactured by Hodogaya Chemical Co., Ltd.), quaternary ammonium salt copy charge PSY VP2038, triphenylmethane derivative copy blue PR, quaternary ammonium salt copy charge NEG VP2036, copy charge NX VP434 ( As mentioned above, manufactured by Hoechst Co., Ltd.), LRA-901, LR-147 (Japanese car) which is a boron complex Tsu DOO Ltd.), copper phthalocyanine, perylene, quinacridone, azo pigments, sulfonate group, a carboxyl group, polymer compounds having a functional group such as quaternary ammonium salts, and the like.
By selectively containing the charge control agent in the resin phase in the toner particle main body existing in the inner layer, the spent of the charge control agent on other members such as a photoreceptor and a carrier can be suppressed. In the toner manufacturing method of the present invention, the arrangement of the charge control agent may be designed relatively freely, and an arbitrary arrangement may be taken according to each image forming process.
The content of the charge control agent with respect to the toner varies depending on the type of the resin, the presence or absence of the additive, the dispersion method, and the like, and cannot be generally specified. For example, the content is 0.1% with respect to 100 parts by mass of the binder resin. -10 mass parts is preferable, and 0.2-5 mass parts is more preferable. When the content of the charge control agent is less than 0.1 parts by mass, the charge controllability may not be obtained. When the content exceeds 10 parts by mass, the chargeability of the toner becomes too large, By reducing the effect, the electrostatic attraction force with the developing roller may increase, leading to a decrease in developer fluidity and a decrease in image density.

(Non-crystalline polyester resin)
In the present invention, an amorphous unmodified polyester resin can be preferably used as the binder resin component. It is preferable that at least a part of the modified polyester resin obtained by crosslinking and / or elongation reaction of the binder resin precursor made of the modified polyester resin is compatible with the unmodified polyester resin.
Thereby, low temperature fixability and hot offset resistance can be improved. For this reason, it is preferable that the polyol and polycarboxylic acid of the modified polyester resin and the unmodified polyester resin have similar compositions. Further, as the unmodified polyester resin, the non-modified polyester resin used in the crystalline polyester dispersion can also be used as long as it is unmodified.
The acid value of the unmodified polyester resin is usually 1 to 50 KOHmg / g, preferably 5 to 30 KOHmg / g. As a result, since the acid value is 1 KOHmg / g or more, the toner is likely to be negatively charged, and further, the affinity between the paper and the toner is improved at the time of fixing to the paper, and the low-temperature fixability can be improved. . However, if the acid value exceeds 50 KOHmg / g, the charging stability, particularly the charging stability against environmental fluctuations, may be reduced. In the present invention, the unmodified polyester resin preferably has an acid value of 1 to 50 KOHmg / g.

The hydroxyl value of the unmodified polyester resin is preferably 5 KOHmg / g or more.
The hydroxyl value is measured using a method based on JIS K0070-1966.
Specifically, first, 0.5 g of a sample is precisely weighed into a 100 ml volumetric flask, and 5 ml of an acetylating reagent is added thereto. Next, after heating in a 100 ± 5 ° C. warm bath for 1-2 hours, the flask is removed from the warm bath and allowed to cool. Furthermore, acetic anhydride is decomposed by adding water and shaking.
Next, in order to completely decompose acetic anhydride, the flask is again heated in a warm bath for 10 minutes or more and allowed to cool, and then the wall of the flask is thoroughly washed with an organic solvent.
Furthermore, the hydroxyl value was measured at 23 ° C. using an automatic potentiometric titrator DL-53 Titrator (manufactured by METTLER TOLEDO) and electrode DG113-SC (manufactured by METTLER TOLEDO), and analysis software LabX Light Version 1.00 Analyze using .000. For calibration of the apparatus, a mixed solvent of 120 ml of toluene and 30 ml of ethanol is used.
At this time, the measurement conditions are as follows.
Stir
Speed [%] 25
Time [s] 15
EQP titration
Titrant / Sensor
Titrant CH3ONa
Concentration [mol / L] 0.1
Sensor DG115
Unit of measurement mV
Predispensing to volume
Volume [mL] 1.0
Wait time [s] 0
Titrant addition Dynamic
dE (set) [mV] 8.0
dV (min) [mL] 0.03
dV (max) [mL] 0.5
Measurement mode Equilibrium controlled
dE [mV] 0.5
dt [s] 1.0
t (min) [s] 2.0
t (max) [s] 20.0
Recognition
Threshold 100.0
Steppes jump only No
Range No
Tendency None
Termination
at maximum volume [mL] 10.0
at potential No
at slope No
after number EQPs Yes
n = 1
comb. termination conditions No
Evaluation
Procedure Standard
Potential1 No
Potentialial No
Stop for revaluation No

The urea-modified polyester resin can be used in combination with a polyester resin modified with a chemical bond other than a urea bond, for example, a polyester resin modified with a urethane bond, in addition to an unmodified polyester resin.
When the toner composition contains a modified polyester resin such as a urea-modified polyester resin, the modified polyester resin can be produced by a one-shot method or the like.

As an example, a method for producing a urea-modified polyester resin will be described.
First, a polyol and a polycarboxylic acid are heated to 150 to 280 ° C. in the presence of a catalyst such as tetrabutoxy titanate or dibutyltin oxide, and if necessary, water generated while removing pressure is removed to have a hydroxyl group. A polyester resin is obtained. Next, a polyester resin having a hydroxyl group is reacted with polyisocyanate at 40 to 140 ° C. to obtain a polyester prepolymer having an isocyanate group. Furthermore, the polyester prepolymer having an isocyanate group is reacted with amines at 0 to 140 ° C. to obtain a urea-modified polyester resin.
The number average molecular weight of the urea-modified polyester resin is usually 1000 to 10000, preferably 1500 to 6000.

In addition, when making the polyester resin which has a hydroxyl group and polyisocyanate react, and when making the polyester prepolymer which has an isocyanate group, and amines react, a solvent can also be used as needed.
Solvents include aromatic solvents (toluene, xylene, etc.); ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.); esters (ethyl acetate, etc.); amides (dimethylformamide, dimethylacetamide, etc.); ethers (tetrahydrofuran) And the like which are inert with respect to the isocyanate group.
In addition, when using unmodified polyester resin together, you may mix to the solution after reaction of the urea modified polyester resin what was manufactured similarly to the polyester resin which has a hydroxyl group.
In the present invention, as the binder resin component contained in the oil phase, a crystalline polyester resin, an amorphous polyester resin, a binder resin precursor, and an unmodified resin may be used in combination. The binder resin component may be contained. The binder resin component preferably contains a polyester resin, and more preferably contains 50% by weight or more of the polyester resin. If the content of the polyester resin is less than 50% by weight, the low-temperature fixability may be lowered. It is particularly preferable that all of the binder resin components are polyester resins.

  Examples of binder resin components other than polyester resins include polystyrene, poly (p-chlorostyrene), styrene-substituted polymers such as polyvinyltoluene, styrene-substituted polymers, styrene-p-chlorostyrene copolymers, and styrene-propylene copolymers. Polymer, styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer, styrene-butyl acrylate copolymer, styrene-acrylic acid Octyl copolymer, styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate copolymer, styrene-α-chloromethyl methacrylate copolymer, styrene-acrylonitrile copolymer , Styrene-vinyl methyl ketone copolymer Styrene copolymers such as styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-acrylonitrile-indene copolymer, styrene-maleic acid copolymer, styrene-maleic acid ester copolymer; Methyl acid, polybutyl methacrylate, polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, epoxy resin, epoxy polyol resin, polyurethane resin, polyamide resin, polyvinyl butyral, polyacrylic acid resin, rosin, modified rosin, terpene resin, fat Aromatic or alicyclic hydrocarbon resin, aromatic petroleum resin, chlorinated paraffin, paraffin wax and the like.

(Inorganic fine particles)
In addition to the porous silica fine particles used in the present invention, inorganic fine particles can be used as external additives for imparting fluidity, developability, chargeability and the like to the toner particles. The inorganic fine particles are not particularly limited and can be appropriately selected from known ones according to the purpose. For example, silica, alumina, titanium oxide, barium titanate, magnesium titanate, calcium titanate, titanate Strontium, zinc oxide, tin oxide, silica sand, clay, mica, wollastonite, diatomaceous earth, chromium oxide, cerium oxide, pengala, antimony trioxide, magnesium oxide, zirconium oxide, barium sulfate, barium carbonate, calcium carbonate, carbonized Silicon, silicon nitride, or the like can be used. These may be used individually by 1 type and may use 2 or more types together.

(Fluidity improver)
A fluidity improver is an agent that increases surface hydrophobicity by surface treatment and prevents deterioration of flow characteristics and charging characteristics even under high humidity. For example, a silane coupling agent, a silylating agent, and a fluoride are used. Silane coupling agents having an alkyl group, organic titanate coupling agents, aluminum coupling agents, silicone oils, modified silicone oils, and the like. Silica and titanium oxide are particularly preferably subjected to surface treatment with such a fluidity improver and used as hydrophobic silica and hydrophobic titanium oxide.

(Cleaning improver)
The cleaning improver is an agent added to the toner in order to remove the developer after transfer remaining on the photoreceptor or the primary transfer medium. For example, fatty acid such as zinc stearate, calcium stearate, stearic acid Examples thereof include polymer fine particles produced by soap-free emulsion polymerization such as metal salts, polymethyl methacrylate fine particles, and polystyrene fine particles. The polymer fine particles preferably have a relatively narrow particle size distribution, and those having a volume average particle size of 0.01 to 1 μm are suitable.

(Magnetic material)
There is no restriction | limiting in particular as a magnetic material, According to the objective, it can select suitably from well-known things, For example, iron powder, a magnetite, a ferrite, etc. can be used. Among these, white is preferable in terms of color tone.

[Method for Producing Toner of the Present Invention]
In the method for producing a toner of the present invention, a melt or dispersion formed by dissolving or dispersing a binder resin or a toner material (toner raw material) mainly composed of a binder resin raw material and a colorant in an organic solvent. The desired toner can be produced by emulsifying or dispersing the toner in an aqueous medium to prepare an emulsified or dispersed liquid. Preferably, a solution or dispersion of a toner material containing at least an active hydrogen group-containing compound and a polymer capable of reacting with the active hydrogen group-containing compound is emulsified or dispersed in an aqueous medium, and the active hydrogen is contained in the aqueous medium. A desired toner is produced by reacting a group-containing compound with a polymer capable of reacting with an active hydrogen group-containing compound to produce toner precursor particles containing at least an adhesive substrate.

(Dissolution or dispersion of toner material)
The solution or dispersion of the toner material is prepared by dissolving or dispersing the toner material in a solvent.
The toner material is not particularly limited as long as the toner can be formed, and can be appropriately selected according to the purpose. For example, the active hydrogen group-containing compound and a polymer (pre-polymer capable of reacting with the active hydrogen group-containing compound) can be selected. Any of the above-mentioned other components such as an unmodified polyester resin, a mold release agent, a colorant, and a charge control agent. The toner material dissolved or dispersed liquid is preferably prepared by dissolving or dispersing the toner material in an organic solvent. The organic solvent is preferably removed during or after the toner granulation.

(Organic solvent)
The organic solvent that dissolves or disperses the toner material is not particularly limited as long as it is a solvent that can dissolve or disperse the toner material, and can be appropriately selected according to the purpose. Preferred are those having a boiling point of less than 150 ° C. from the viewpoint of ease of removal, for example, toluene, xylene, benzene, carbon tetrachloride, methylene chloride, 1,2-dichloroethane, 1,1,2-trichloroethane, trichloroethylene, chloroform In addition to water-insoluble solvents such as monochlorobenzene, dichloroethylidene, methyl acetate, and ethyl acetate, water-miscible solvents such as methyl ethyl ketone and methyl isobutyl ketone can be used. Further, ester solvents are preferable, and ethyl acetate is particularly preferable. These may be used individually by 1 type and may use 2 or more types together. There is no restriction | limiting in particular as the usage-amount of an organic solvent, Although it can select suitably according to the objective, 40-300 mass parts is preferable with respect to 100 mass parts of toner materials, 60-140 mass parts is more preferable, 80 -120 mass parts is more preferable. The toner material is dissolved or dispersed in an organic solvent containing an active hydrogen group-containing compound, a polymer capable of reacting with the active hydrogen group-containing compound, an unmodified polyester resin, a release agent, a colorant, and charge control. The toner material such as an agent can be dissolved or dispersed.
In the toner material, components other than the polymer (prepolymer) capable of reacting with the active hydrogen group-containing compound may be added and mixed in the aqueous medium in the preparation of the aqueous medium described later. When the dissolved or dispersed liquid of the toner material is added to the aqueous medium, it may be added to the aqueous medium together with the dissolved or dispersed liquid.

(Aqueous medium)
The aqueous medium is not particularly limited and can be appropriately selected from known ones. For example, water, a solvent miscible with water, a mixture thereof, and the like can be used. Is particularly preferred. The solvent miscible with water is not particularly limited as long as it is miscible with water. For example, alcohol, dimethylformamide, tetrahydrofuran, Cellsorb (registered trademark), lower ketones, and the like can be used. Examples of the alcohol include methanol, isopropanol, and ethylene glycol. Examples of lower ketones include acetone and methyl ethyl ketone. These may be used individually by 1 type and may use 2 or more types together.

(Emulsification or dispersion)
The dissolution or dispersion of the toner material in the aqueous medium is preferably carried out by dispersing the toner material dissolution or dispersion in the aqueous medium while stirring. There is no restriction | limiting in particular as a dispersion method, According to the objective, it can select suitably, For example, it can carry out using a well-known disperser etc. Examples of the disperser include a low speed shear disperser and a high speed shear disperser. In this toner production method, an adhesive base material is formed when an active hydrogen group-containing compound and a polymer capable of reacting with the active hydrogen group-containing compound are subjected to an extension reaction or a crosslinking reaction during emulsification or dispersion. .

(Adhesive substrate)
The adhesive base material is an adhesive polymer obtained by reacting an active hydrogen group-containing compound and a polymer capable of reacting with the active hydrogen group-containing compound in an aqueous medium. It is preferable to contain. Note that a binder resin appropriately selected from known binder resins may be included.
There is no restriction | limiting in particular as a weight average molecular weight of an adhesive base material, Although it can select suitably according to the objective, 3,000 or more are preferable, 5,000-1,000,000 are more preferable, 7, 000 to 500,000 is particularly preferred. This is because if the weight average molecular weight is less than 3,000, the hot offset resistance may deteriorate.

There is no restriction | limiting in particular as glass transition temperature (Tg) of an adhesive base material, Although it can select suitably according to the objective, For example, 30-70 degreeC is preferable and 40-65 degreeC is more preferable.
This is because if the glass transition temperature (Tg) is less than 30 ° C., the heat-resistant storage stability of the toner may deteriorate, and if it exceeds 70 ° C., the low-temperature fixability may not be sufficient. In the electrophotographic toner of the present embodiment, since a polyester resin subjected to a crosslinking reaction and an extension reaction coexists, good storability is exhibited even when the glass transition temperature is lower than that of a conventional polyester toner.
The glass transition temperature (Tg) is measured by the following method using, for example, a TG-DSC system TAS-100 (manufactured by Rigaku Corporation). First, about 10 mg of toner is placed in an aluminum sample container, and the sample container is placed on a holder unit and set in an electric furnace. After heating from room temperature to 150 ° C. at a rate of temperature increase of 10 ° C./min, the sample is left at 150 ° C. for 10 minutes, and the sample is cooled to room temperature and left for 10 minutes. Then, the DSC curve is measured with a differential scanning calorimeter (DSC) after heating to 150 ° C. at a temperature rising rate of 10 ° C./min in a nitrogen atmosphere.
From the obtained DSC curve, using the analysis system in the TG-DSC system TAS-100 system, the glass transition temperature (Tg) is calculated from the contact point between the tangent line of the endothermic curve near the glass transition temperature (Tg) and the baseline. To do.

  There is no restriction | limiting in particular as resin for adhesive base materials, Although it can select suitably according to the objective, A polyester-type resin etc. are especially suitable. There is no restriction | limiting in particular as a polyester-type resin, Although it can select suitably according to the objective, For example, a urea modified polyester-type resin etc. are mentioned as a particularly suitable thing. The urea-modified polyester resin comprises an amine (B) as an active hydrogen group-containing compound and an isocyanate group-containing polyester prepolymer (A) as a polymer that can react with the active hydrogen group-containing compound in an aqueous medium. Obtained by reaction. The urea-modified polyester resin may contain a urethane bond in addition to the urea bond. In this case, the content molar ratio of the urea bond and the urethane bond (urea bond / urethane bond) is not particularly limited and may be appropriately selected depending on the intended purpose, but is 100/0 to 10/90. Preferably, 80/20 to 20/80 is more preferable, and 60/40 to 30/70 is particularly preferable. This is because if the urea bond is less than 10, the hot offset resistance may be deteriorated.

Preferable specific examples of the urea-modified polyester resin include the following.
(1) A polyester prepolymer obtained by reacting a polycondensate of bisphenol A ethylene oxide 2 mol adduct and isophthalic acid with isophorone diisocyanate and uread with isophorone diamine, bisphenol A ethylene oxide 2 mol adduct and isophthalic acid Mixture with polycondensate (2) Polyester prepolymer obtained by reacting 2-condensate of bisphenol A ethylene oxide with polycondensate of isophthalic acid with isophorone diisocyanate and urea of bisphenol A ethylene oxide with 2 moles Mixture of adduct and polycondensate of terephthalic acid (3) Bisphenol A ethylene oxide 2 mol adduct / bisphenol A propylene oxide 2 mol adduct and terephthalic acid polycondensate Mixture of polyester prepolymer reacted with rondiisocyanate urea-isolated with isophoronediamine and bisphenol A ethylene oxide 2-mole adduct / bisphenol A propylene oxide 2-mole adduct and polycondensate of terephthalic acid (4) bisphenol Polyester prepolymer obtained by reacting polycondensate of A ethylene oxide 2 mol adduct / bisphenol A propylene oxide 2 mol and terephthalic acid with isophorone diisocyanate and 2 mol addition of bisphenol A propylene oxide 2 And a mixture of a polycondensate of terephthalic acid and (5) reacting a 2-mole adduct of bisphenol A ethylene oxide and a polycondensate of terephthalic acid with isophorone diisocyanate. Mixture of polyester prepolymer uread with hexamethylenediamine and polycondensate of bisphenol A ethylene oxide 2 mol adduct and terephthalic acid (6) Polycondensation of bisphenol A ethylene oxide 2 mol adduct and terephthalic acid A mixture of a polyester prepolymer obtained by reacting a product with isophorone diisocyanate and uread with hexamethylenediamine, and a polycondensate of bisphenol A ethylene oxide 2-mole adduct / bisphenol A propylene oxide 2-mole adduct and terephthalic acid ( 7) A polyester prepolymer obtained by reacting a bicondensate of bisphenol A ethylene oxide 2 mol and a polycondensate of terephthalic acid with isophorone diisocyanate and uread with ethylenediamine, and bisphenol (8) Polyester prepolymer obtained by reacting a polycondensate of bisphenol A ethylene oxide 2 mol adduct and isophthalic acid with diphenylmethane diisocyanate was converted to hexamethylene. Mixture of urealated diamine and polycondensate of bisphenol A ethylene oxide 2 mol adduct and isophthalic acid (9) bisphenol A ethylene oxide 2 mol adduct / bisphenol A propylene oxide 2 mol adduct and terephthalic acid / A polyester prepolymer obtained by reacting a polycondensate of dodecenyl succinic anhydride with diphenylmethane diisocyanate and uread with hexamethylenediamine, and a bisphenol A ethylene oxide 2-mole adduct / Mixture of 2 mol of Sphenol A propylene oxide and polycondensate of terephthalic acid (10) Polyester prepolymer prepared by reacting bisphenol A ethylene oxide 2 mol adduct and isophthalic acid polycondensate with toluene diisocyanate Mixture of urea-modified diamine with bisphenol A ethylene oxide 2-mole adduct and polycondensate of isophthalic acid

  The adhesive substrate (for example, a urea-modified polyester resin) is, for example, (1) a toner material containing a polymer (for example, an isocyanate group-containing polyester prepolymer (A)) that can react with an active hydrogen group-containing compound. The dispersion is emulsified or dispersed in an aqueous medium together with an active hydrogen group-containing compound (for example, amines (B)), oil droplets are formed, and both are subjected to an extension reaction or a crosslinking reaction in the aqueous medium. (2) A solution or dispersion of the toner material is emulsified or dispersed in an aqueous medium to which an active hydrogen group-containing compound has been added in advance to form oil droplets, and both are elongated in the aqueous medium. It may be produced by a reaction or a crosslinking reaction. Alternatively, (3) a toner material solution or dispersion is added and mixed in an aqueous medium, then an active hydrogen group-containing compound is added to form oil droplets, and both extend from the particle interface in the aqueous medium. It may be produced by a reaction or a crosslinking reaction. In the case of (3), the modified polyester resin is preferentially produced on the surface of the toner to be produced, and it becomes possible to provide a concentration gradient on the toner particles.

  The reaction conditions for producing an adhesive substrate by emulsification or dispersion are not particularly limited, and are appropriately selected according to the combination of the polymer capable of reacting with the active hydrogen group-containing compound and the active hydrogen group-containing compound. be able to. In addition, as reaction time, 10 minutes-40 hours are preferable, and 2 hours-24 hours are more preferable.

  Examples of a method for stably forming a dispersion containing a polymer capable of reacting with an active hydrogen group-containing compound (for example, an isocyanate group-containing polyester prepolymer (A)) in an aqueous medium include, for example, an activity in an aqueous medium. Dissolve or disperse a toner material such as a polymer capable of reacting with a hydrogen group-containing compound (for example, an isocyanate group-containing polyester prepolymer (A)), a colorant, a release agent, a charge control agent, and an unmodified polyester resin in an organic solvent. For example, a method of adding a solution or dispersion of a toner material prepared in such a manner and dispersing the toner material by shearing force may be used.

  In emulsification or dispersion, the amount of the aqueous medium used is preferably 50 to 2,000 parts by mass, more preferably 100 to 1,000 parts by mass with respect to 100 parts by mass of the toner material. This is because if the amount used is less than 50 parts by mass, the toner material is poorly dispersed and toner particles having a predetermined particle size may not be obtained. If the amount used exceeds 2,000 parts by mass, the production cost is high. Because it becomes.

Examples of the polymeric protective colloid include acids, (meth) acrylic monomers containing hydroxyl groups, vinyl alcohol or ethers of vinyl alcohol, esters of vinyl alcohol and a compound containing a carboxyl group, amide compounds Alternatively, homopolymers or copolymers such as those having methylol compounds, chlorides, nitrogen atoms or heterocyclic rings thereof, polyoxyethylenes, celluloses, and the like can be given. Examples of the acids include acrylic acid, methacrylic acid, α-cyanoacrylic acid, α-cyanomethacrylic acid, itaconic acid, crotonic acid, fumaric acid, maleic acid, maleic anhydride, and the like. Examples of the (meth) acrylic monomer containing a hydroxyl group include β-hydroxyethyl acrylate, β-hydroxyethyl methacrylate, β-hydroxypropyl acrylate, β-hydroxypropyl methacrylate, and γ-acrylate. Hydroxypropyl, γ-hydroxypropyl methacrylate, 3-chloro-2-hydroxypropyl acrylate, 3-chloro-2-hydroxypropyl methacrylate, diethylene glycol monoacrylate, diethylene glycol monomethacrylate, glycerin monoacrylate, Examples include glycerin monomethacrylate, N-methylol acrylamide, N-methylol methacrylamide and the like.
Examples of vinyl alcohol or ethers with vinyl alcohol include vinyl methyl ether, vinyl ethyl ether, vinyl propyl ether, and the like. Examples of esters of a compound containing vinyl alcohol and a carboxyl group include vinyl acetate, vinyl propionate, and vinyl butyrate. Moreover, as an amide compound or these methylol compounds, acrylamide, methacrylamide, diacetone acrylamide acid, or these methylol compounds etc. are mentioned, for example.
Examples of chlorides include acrylic acid chloride and methacrylic acid chloride. Examples of homopolymers or copolymers having a nitrogen atom or a heterocyclic ring thereof include, for example, vinyl pyridine, vinyl pyrrolidone, vinyl imidazole, and ethylene imine.
Examples of the polyoxyethylene type include polyoxyethylene, polyoxypropylene, polyoxyethylene alkylamine, polyoxypropylene alkylamine, polyoxyethylene alkylamide, polyoxypropylene alkylamide, polyoxyethylene nonylphenyl ether, polyoxyethylene Examples include ethylene lauryl phenyl ether, polyoxyethylene stearyl phenyl ester, and polyoxyethylene nonyl phenyl ester. Examples of celluloses include methyl cellulose, hydroxyethyl cellulose, and hydroxypropyl cellulose.

  When using a dispersion stabilizer that is soluble in acids and alkalis such as calcium phosphate, remove the calcium phosphate from the fine particles by dissolving the calcium phosphate with an acid such as hydrochloric acid and then washing with water or decomposing with an enzyme. It becomes possible to do.

(Removal of organic solvent)
The organic solvent is removed from the emulsified slurry obtained by emulsification or dispersion. The organic solvent is removed by (1) a method of gradually raising the temperature of the entire reaction system to completely evaporate and remove the organic solvent in the oil droplets, and (2) spraying the emulsified dispersion in a dry atmosphere, Examples thereof include a method in which the water-insoluble organic solvent in the droplets is completely removed to form toner fine particles, and the aqueous dispersant is removed by evaporation. When the organic solvent is removed, toner particles are formed. The formed toner particles are washed, dried, etc., and then classified as desired. The classification is performed, for example, by removing fine particle portions in a liquid by a cyclone, a decanter, centrifugation, or the like. The classification operation may be performed after obtaining the powder after drying.

  The toner particles thus obtained are mixed with particles such as a colorant, a release agent, and a charge control agent, and further a mechanical impact force is applied to the particles such as a release agent from the surface of the toner particles. Can be prevented from desorbing. As a method of applying a mechanical impact force, for example, a method of applying an impact force to a mixture with a blade rotating at high speed, a mixture of particles in a high-speed air stream and acceleration to mix particles or a composite particle is a suitable collision plate. And the like. As an apparatus used in this method, for example, an ong mill (manufactured by Hosokawa Micron Co., Ltd.), an I-type mill (manufactured by Nippon Pneumatic Co., Ltd.) and a pulverization air pressure is lowered, a hybridization system (Nara Machinery) Mfg. Co., Ltd.), Kryptron System (manufactured by Kawasaki Heavy Industries, Ltd.), automatic mortar, and the like.

  Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples. In addition, this invention is not limited to the Example and comparative example which are illustrated here. In addition, the part in an Example represents a mass part unless there is particular description.

[Production of toner]
A specific preparation example of the toner used for evaluation will be described. The toner used in the present invention is not limited to these examples.

(Preparation of solution or dispersion of toner material)
~ Synthesis of unmodified polyester (low molecular weight polyester) ~
In a reaction vessel equipped with a cooling tube, a stirrer and a nitrogen introduction tube, 67 parts by mass of bisphenol A ethylene oxide 2 mol adduct, 84 parts by mass of bisphenol A propion oxide 3 mol adduct, 274 parts by mass of terephthalic acid, and dibutyltin oxide 2 parts by mass were added and reacted at 230 ° C. under normal pressure for 8 hours. Next, the reaction solution was reacted under reduced pressure of 10 to 15 mmHg for 5 hours to synthesize an unmodified polyester.
The obtained unmodified polyester had a number average molecular weight (Mn) of 2,100, a weight average molecular weight (Mw) of 5,600, and a glass transition temperature (Tg) of 55 ° C.

-Preparation of masterbatch (MB)-
1000 parts by mass of water, 540 parts by mass of carbon black (“Printex35”; manufactured by Degussa, DBP oil absorption = 42 ml / 100 g, pH = 9.5), and 1200 parts by mass of the unmodified polyester were combined with a Henschel mixer (Mitsui Mine). Mixed). The mixture was kneaded for 30 minutes at 150 ° C. with two rolls, rolled and cooled, and pulverized with a pulverizer (manufactured by Hosokawa Micron) to prepare a master batch.

~ Preparation of wax dispersion ~
In a reaction vessel equipped with a stirring bar and a thermometer, 378 parts of unmodified polyester resin (1), 110 parts of carnauba wax, 22 parts of salicylic acid metal complex E-84 (manufactured by Orient Chemical Co., Ltd.) and 947 parts of ethyl acetate are charged. While stirring, the temperature was raised to 80 [° C.], maintained at 80 [° C.] for 5 [hours], and then cooled to 30 [° C.] over 1 [hour]. Next, 500 parts of master batch (1) and 500 parts of ethyl acetate were charged into the reaction vessel, and mixed for 1 [hour] to obtain a raw material solution (1).
1324 parts of the obtained raw material solution (1) was transferred to a reaction vessel and filled with 80 [volume%] of 0.5 mm zirconia beads using an ultraviscomil (made by Imex Co., Ltd.), a bead mill. [Kg / hr], disk pass speed is 6 [m / sec], 3 passes, C.I. I. Pigment Red and carnauba wax were dispersed to obtain a wax dispersion (1).

~ Preparation of dispersion of toner material ~
Next, 1324 parts of a 65% by weight ethyl acetate solution of the unmodified polyester resin (1) was added to the wax dispersion (1). A layered inorganic mineral montmorillonite (Clayton APA Southern Clay modified at least partly with a quaternary ammonium salt having a benzyl group) was added to 200 parts of a dispersion obtained by one pass using Ultraviscomyl under the same conditions as above. (Products) 1.0 part was added. K. Using a homodisper (manufactured by Koki Kogyo Co., Ltd.), the mixture was stirred for 30 minutes to obtain a dispersion (1) of toner material.

(Manufacture of toner a)
-Preparation of aqueous medium phase-
660 parts by mass of water, 25 parts by mass of the fine particle dispersion A1, 25 parts by mass of an aqueous solution of 48.5% by mass of sodium dodecyl diphenyl ether disulfonate (“Eleminol MON-7”; manufactured by Sanyo Chemical Industries), and 60 parts by mass of ethyl acetate The parts were mixed and stirred to obtain a milky white liquid (aqueous phase). When observed with an optical microscope, several hundred μm aggregates were observed. When this aqueous medium phase was stirred at 8000 rpm using a TK homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.), it was confirmed by an optical microscope that the aggregates were loosened and could be dispersed into small aggregates of several μm.

~ Emulsification or preparation of dispersion ~
150 parts by mass of the aqueous medium phase is put in a container, and stirred at a rotational speed of 12,000 rpm using a TK homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.), and 100 parts by mass of the toner material dispersion (1) is added thereto. Was added and mixed for 10 minutes to prepare an emulsified or dispersed liquid (emulsified slurry).

~ Removal of organic solvent ~
Into a flask equipped with a deaeration pipe, a stirrer and a thermometer, 100 parts by mass of the emulsified slurry was charged, and the solvent was removed under reduced pressure at 30 ° C. for 12 hours while stirring at a stirring peripheral speed of 20 m / min. did. Thereafter, the dispersion was heated to 60 ° C. to immobilize the resin fine particles B1 adhering to the toner surface.

~ Washing and drying ~
After filtering the whole amount of the solvent removal slurry under reduced pressure, 300 parts by mass of ion-exchanged water was added to the filter cake, mixed and redispersed (at 12,000 rpm for 10 minutes) with a TK homomixer, and then filtered. To the obtained filter cake, 300 parts by mass of ion-exchanged water was added and mixed with a TK homomixer (at 12,000 rpm for 10 minutes) and then filtered three times. The obtained filter cake was dried at 45 ° C. for 48 hours with a forward air dryer and sieved with a mesh having a mesh size of 75 μm to obtain toner base particles a.

~ External treatment ~
0.11 part by mass of porous silica fine particles S1 (average primary particle size 20 nm, specific surface area 480 m ² / g) having an average particle size of 20 nm with respect to 100 parts by mass of toner base particles a and titanium oxide having an average particle size of 20 nm 1.0 part by mass was mixed with a Henschel mixer to obtain toner a.

(Manufacture of toner b to toner q)
The evaluation result of the obtained toner a is set as Example 1, the manufacturing conditions of the toner a are set as Examples 2 to 10 and Comparative Examples 1 to 7, and the following conditions are changed and porous silica fine particles as shown in Table 1 are used. The toner b to the toner j and the toner k to the toner q were respectively prepared by changing. The production conditions not described such as the amount used were the same as the production conditions for toner a.

The amount of layered inorganic mineral montmorillonite added was changed to 0.8 part, and the externally added porous silica fine particles were changed to S2 (average primary particle size 180 nm, specific surface area 25 m ² / g, true specific gravity, 1.8 g / cm ³ ). A toner b was produced in the same manner as in Example 1 except that 1.05 part was added.

The amount of layered inorganic mineral montmorillonite added was changed to 0.6 part, and the externally added porous silica fine particles were changed to S2 (average primary particle size 20 nm, specific surface area 480 m ² / g, true specific gravity, 2.0 g / cm ³ ). A toner c was produced in the same manner as in Example 1 except that the content was changed to 0.42 part addition.

Example 1 except that S2 (average primary particle size 180 nm, specific surface area 25 m ² / g, true specific gravity, 1.8 g / cm ³ ) was changed to 4.19 parts for the externally added porous silica fine particles. The toner d was manufactured.

The amount of layered inorganic mineral montmorillonite added was changed to 0.8 parts, and externally added porous silica fine particles were changed to S3 (average primary particle size 50 nm, specific surface area 250 m ² / g, true specific gravity, 1.7 g / cm ³ ). A toner e was produced in the same manner as in Example 1 except that 0.75 parts was added.

The amount of layered inorganic mineral montmorillonite added was changed to 0.6 part, and externally added porous silica fine particles were changed to S4 (average primary particle size 100 nm, specific surface area 50 m ² / g, true specific gravity, 1.8 g / cm ³ ). A toner f was produced in the same manner as in Example 1 except that 0.85 parts was added.

The layered inorganic mineral montmorillonite is changed to an organosilica sol (MEK-ST-UP, solid content concentration 20%, average primary particle size 15 nm, manufactured by Nissan Chemical Industries, Ltd.). The silica fine particles were produced in the same manner as in Example 1 except that S5 (average primary particle size 80 nm, specific surface area 100 m ² / g, true specific gravity, 1.9 g / cm ³ ) was added to 0.53 parts, and toner g Was made.

The layered inorganic mineral montmorillonite is changed to organosilica sol (MEK-ST-UP, solid content concentration 20%, average primary particle size 15 nm, manufactured by Nissan Chemical Industries), the addition amount is changed to 18 parts, and externally added porous A silica fine particle was produced in the same manner as in Example 1 except that S4 (average primary particle size 100 nm, specific surface area 60 m ² / g, true specific gravity, 1.8 g / cm ³ ) was changed to 1.05 part addition, and toner h Was made.

The layered inorganic mineral montmorillonite is changed to an organosilica sol (MEK-ST-UP, solid content concentration 20%, average primary particle size 15 nm, manufactured by Nissan Chemical Industries, Ltd.). The silica fine particles were produced in the same manner as in Example 1 except that S3 (average primary particle size 50 nm, specific surface area 250 m ² / g, true specific gravity, 1.7 g / cm ³ ) was changed to 0.74 part addition, and toner i Was made.

The layered inorganic mineral montmorillonite is changed to organosilica sol (MEK-ST-UP, solid content concentration 20%, average primary particle size 15 nm, manufactured by Nissan Chemical Industries, Ltd.). The silica fine particles were produced in the same manner as in Example 1 except that S2 (average primary particle size 180 nm, specific surface area 25 m ² / g, true specific gravity, 2.0 g / cm ³ ) was changed to 1.05 part addition, and toner j Was made.

(Comparative Example 1)
Except that the porous silica fine particles to be externally added were changed to 0.08 part addition of S6 (average primary particle size 15 nm, specific surface area 500 m ² / g, true specific gravity, 1.8 g / cm ³ ), as in Example 1. The toner k was manufactured.

(Comparative Example 2)
The amount of layered inorganic mineral montmorillonite added was changed to 0.8 part, and externally added porous silica fine particles were changed to S7 (average primary particle size 250 nm, specific surface area 20 m ² / g, true specific gravity, 1.7 g / cm ³ ). A toner l was produced in the same manner as in Example 1 except that 4.95 parts was added.

(Comparative Example 3)
The amount of layered inorganic mineral montmorillonite added was changed to 0.6 part, and externally added porous silica fine particles were changed to S4 (average primary particle size 100 nm, specific surface area 480 m ² / g, true specific gravity, 1.8 g / cm ³ ). A toner m was produced in the same manner as in Example 1 except that 0.1 part was added.

(Comparative Example 4)
The layered inorganic mineral montmorillonite is changed to organosilica sol (MEK-ST-UP, solid content concentration 20%, average primary particle size 15 nm, manufactured by Nissan Chemical Industries, Ltd.), the addition amount is changed to 20 parts, and externally added porous The silica fine particles were produced in the same manner as in Example 1 except that S2 (average primary particle size 180 nm, specific surface area 25 m ² / g, true specific gravity, 2.0 g / cm ³ ) was changed to 5.23 parts, and toner n Was made.

(Comparative Example 5)
The layered inorganic mineral montmorillonite is changed to organosilica sol (MEK-ST-UP, solid content concentration 20%, average primary particle size 15 nm, manufactured by Nissan Chemical Industries, Ltd.), and the addition amount is changed to 16 parts. The silica fine particles were produced in the same manner as in Example 1 except that S8 (average primary particle size 120 nm, specific surface area 40 m ² / g, true specific gravity, 2.1 g / cm ³ ) was changed to 1.46 parts, and toner o Was made.

(Comparative Example 6)
Except that the porous silica fine particles to be externally added were changed to S8 (average primary particle size 100 nm, specific surface area 15 m ² / g, true specific gravity, 2.0 g / cm ³ ) added to 0.08 parts, as in Example 1. The toner p was manufactured.

(Comparative Example 7)
The amount of layered inorganic mineral montmorillonite added was changed to 0.8 part, and the externally added porous silica fine particles were changed to S8 (average primary particle size 120 nm, specific surface area 600 m ² / g, true specific gravity, 1.9 g / cm ³ ). A toner q was produced in the same manner as in Example 1 except that 4.95 parts was added.

[Evaluation item]
(Storage under high humidity environment)
The toner was stored at 35 ° C. and 90% for 14 days, and then sieved with a 200 mesh sieve for 1 minute, and the residual rate on the wire mesh was measured.
At this time, the residual rate of toner having better storage stability in a high humidity environment is smaller.
The storage stability in a high-humidity environment was judged as ◎ when the residual rate was less than 0.1%, ◯ from 0.1% to 1%, and × when 1% or more.

(Charge stability under high temperature and high humidity)
The charge amount is measured by the V blow-off device single mode method.
The toner and the carrier were set to a toner concentration (toner weight / (toner weight + carrier weight)) of 7 wt%, left in a predetermined environment (temperature, humidity) for 2 hours, and stirred and mixed for 6 seconds with a mag roll with a rotation speed of 285 rpm. 1 g of developer was weighed from the initial agent, and the toner charge amount distribution was measured by a single mode method using a V blow-off device (manufactured by Ricoh Creative Development Co., Ltd.). At the time of blowing, an opening of 635 mesh was used.
The measurement conditions of the single mode method are height 5 mm, suction 100, and double blow.
The value of | M−H | is less than 5 μC / g, where H is the toner charge amount at 32 ° C. and 54% relative humidity and M is the toner charge amount at 25 ° C. and 50% relative humidity. , The case of less than 10 μC / g was judged as ◯, and the case of 10 μm or more was judged as x.

(Low temperature fixability)
A copying test was performed on type 6200 paper (manufactured by Ricoh) using an apparatus in which a fixing unit of a copying machine MF2200 (manufactured by Ricoh) using a Teflon (registered trademark) roller as a fixing roller was modified.
Specifically, the cold offset temperature (fixing lower limit temperature) and the hot offset temperature (fixing upper limit temperature) were determined by changing the fixing temperature.
The evaluation conditions for the minimum fixing temperature were a paper feed linear velocity of 120 to 150 mm / second, a surface pressure of 1.2 kgf / cm ² , and a nip width of 3 mm.
The evaluation conditions for the upper limit fixing temperature were a paper feed linear velocity of 50 mm / second, a surface pressure of 2.0 kgf / cm ² , and a nip width of 4.5 mm.
The lower limit fixing temperature of the conventional low-temperature fixing toner is about 140 ° C.
At this time, the fixing lower limit temperature was judged as ◎ when the temperature was less than 120 ° C, ◯ when the temperature was 120 ° C or more and less than 140 ° C, and x when the temperature was 140 ° C or more and less than 150 ° C.

<Filming evaluation method>
1. All toners and devices used for evaluation are left at 25 [° C.] in a 50% environment room for 1 day.
2. All the toner on the PCU of the copier (100) is removed, leaving only the carrier in the developing device 61.
3. In the developing device (61) having only the carrier, 28 [g] of black toner as a sample was charged, and 400 [g] of a developer having a toner concentration of 7 [%] was prepared.
4). The developing device (61) is mounted on the main body of the copying machine (100), the developing sleeve (sleeve forming the surface of the developing roller (61a)) is linearly 300 [mm / s], and only the developing device (61) is installed. [Minute] Allowed to rotate.
5. Both the developing sleeve and the photoconductor (10) are rotated by trailing at a target linear velocity, and the charging potential and the developing bias are set so that the toner on the photoconductor (10) becomes 0.4 ± 0.05 [mg / cm ² ]. Adjusted.
6). Under the above development conditions, the transfer current was adjusted so that the transfer rate was 96 ± 2 [%].
7). Full-page solid images were output continuously at 10,000 [sheets].
8). Sensory evaluation was performed on the image quality of the output image, and the number of white spots due to filming was counted.
The evaluation criteria for filming properties were as follows.
A: Remarkably excellent with few white-out image portions B: Normal white-out portions X: Very many white-out portions The evaluation results of manufactured toners a to q are shown as Examples 1 to 10 and Comparative Examples 1 to 7. It was shown in 1.

DESCRIPTION OF SYMBOLS 10 Photoconductor 10K Black photoconductor 10Y Yellow photoconductor 10M Magenta photoconductor 10C Cyan photoconductor 14, 15, 16 Support roller 17 Intermediate transfer body cleaning device 18 Image forming means 20 Charging roller 21 Exposure device 22 Secondary transfer Device 23 Roller 24 Secondary transfer belt 25 Fixing device 26 Fixing belt 27 Pressure belt 28 Sheet reversing device 30 Exposure device 32 Contact glass 33 First traveling member 34 Second traveling member 35 Imaging lens 36 Reading sensor 40 Developing device 41 Developing Belt 42K, 42Y, 42M, 42C Developer container 43K, 43Y, 43M, 43C Developer supply roller 44K, 44Y, 44M, 44C Developer roller 45K Black developer 45Y Yellow developer 45M Magenta developer 45C Cyan Present Device 49 Registration roller 50 Intermediate transfer member 51 Roller 52 Manual feed tray 53 Manual feed path 55 Switching claw 56 Discharge roller 57 Discharge tray 58 Corona charger 59 Charger 60 Cleaning device 61 Developer 62 Transfer charger 63 Photoconductor cleaning device 64 Static eliminator 70 Static elimination lamp 80 Transfer roller 90 Cleaning device 95 Recording paper 100A, 100B, 100C Image forming device 110 Belt type fixing device 120 Tandem type developer 130 Document table 142a, 142b Paper feed roller 143 Paper bank 144 Paper feed cassette 145a, 145b Separating roller 146 Feeding path 147 Conveying roller 148 Feeding path 150 Copier main body 200 Feeding table 300 Scanner

Japanese Patent No. 3030741 JP 2000-112174 A JP 2001-201891 A JP 2001-235894 A Japanese Patent Laid-Open No. 2001-215663 Japanese Patent Laid-Open No. 2-73362 JP 2008-076421 A

Claims (15)

In an image forming apparatus having a charging unit, an exposure unit, a developing unit, a transfer unit, a fixing unit, and a cleaning unit, the toner used for image formation is a toner produced by aqueous granulation, and the toner base Silica fine particles as an additive on the surface, the silica is porous silica fine particles having fine pores on the surface, and the ratio of the coverage area of the porous silica fine particles to the toner base surface is 5 to 20% And the average primary particle diameter of the porous silica fine particles is 20 to 200 nm, the true specific gravity is 2.0 g / cm ³ or less, and the specific surface area is 20 to 500 m ² / g. apparatus.   The image forming apparatus according to claim 1, wherein a binder resin of the toner is a polyester resin.   The image forming apparatus according to claim 1, wherein the toner contains at least one crystalline polyester resin and at least one amorphous polyester resin as a binder resin component.   The toner is composed of a binder resin, a prepolymer made of a modified polyester resin, a compound that undergoes elongation reaction or crosslinking reaction with the prepolymer, a colorant, a release agent, and at least a part of interlayer ions in the layered inorganic mineral with organic ions. By removing a solvent from a dispersion obtained by emulsifying or dispersing a toner raw material solution or dispersion containing a modified modified layered inorganic mineral in an organic solvent, followed by a crosslinking reaction or elongation reaction. 4. The image forming apparatus according to claim 1, wherein the obtained organic solvent solution or dispersion has a Casson yield value at 25 ° C. of 1 Pa to 100 Pa. 5.   The image forming apparatus according to claim 1, wherein an average circularity A of the toner base particles is in a range of 0.94 ≦ A ≦ 0.99. In an image forming method having at least an image carrier and a charging step, an exposure step, a development step, a transfer step, a fixing step, and a cleaning step, the toner used for the image formation is a toner produced by aqueous granulation. In addition, the surface of the toner base has silica fine particles as an additive, the silica is porous silica fine particles having fine pores on the surface, and the ratio of the coverage area of the porous silica fine particles to the toner base surface is 5 to 20 %, The average primary particle size of the porous silica fine particles is 20 to 200 nm, the true specific gravity is 2.0 g / cm ³ or less, and the specific surface area is 20 to 500 m ² / g. Image forming method.   The image forming method according to claim 6, wherein the binder resin of the toner is a polyester resin.   The image forming method according to claim 6 or 7, wherein the toner contains at least one crystalline polyester resin and at least one amorphous polyester resin as a binder resin component.   The toner is composed of a binder resin, a prepolymer made of a modified polyester resin, a compound that undergoes elongation reaction or crosslinking reaction with the prepolymer, a colorant, a release agent, and at least a part of interlayer ions in the layered inorganic mineral with organic ions. By removing a solvent from a dispersion obtained by emulsifying or dispersing a toner raw material solution or dispersion containing a modified modified layered inorganic mineral in an organic solvent, followed by a crosslinking reaction or elongation reaction. 9. The image forming method according to claim 6, wherein the obtained organic solvent solution or dispersion has a Casson yield value at 25 ° C. of 1 Pa to 100 Pa. 10.   10. The image forming method according to claim 6, wherein an average circularity A of toner base particles of the toner is in a range of 0.94 ≦ A ≦ 0.99. A toner for an image forming method having at least an image carrier, a charging step, an exposure step, a developing step using a developer containing toner, a transfer step, a fixing step, and a cleaning step, and produced by aqueous granulation And having silica fine particles as an additive on the surface of the toner base, the silica being porous silica fine particles having fine pores on the surface, and the ratio of the coverage area of the porous silica fine particles to the surface of the toner base is 5 That the average primary particle diameter of the porous silica fine particles is 20 to 200 nm, the true specific gravity is 2.0 g / cm ³ or less, and the specific surface area is 20 to 500 m ² / g. An electrostatic latent image developing toner.   The toner according to claim 11, wherein the binder resin is a polyester resin.   The toner according to claim 11, wherein the toner contains at least one crystalline polyester resin and at least one amorphous polyester resin as the binder resin component.   Binder resin, prepolymer composed of modified polyester resin, compound that undergoes elongation reaction or cross-linking reaction with the prepolymer, colorant, release agent, modified layered layer in which at least part of interlayer ions in layered inorganic mineral is modified with organic ions By removing a solvent from a dispersion obtained by emulsifying or dispersing a toner raw material solution or dispersion containing an inorganic mineral in an organic solvent in an aqueous medium, followed by a crosslinking reaction or elongation reaction. 13. The toner according to claim 11, wherein the obtained toner has a Casson yield value of 1 Pa to 100 Pa at 25 ° C. of the solution or dispersion of the organic solvent.   The toner according to claim 11, wherein an average circularity A of the toner base particles is in a range of 0.94 ≦ A ≦ 0.99.

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