JP4881601B2 - Cleaning device, image forming apparatus, and process cartridge - Google Patents

Description

  The present invention relates to an electrophotographic image forming apparatus such as a printer, a copier, a FAX, and a multifunction peripheral having at least two functions, and more specifically, an image using a fur brush for removing residuals such as transfer residual toner. The present invention relates to a forming apparatus.

  An image forming apparatus using an electrophotographic process includes a photoconductor as an image carrier, and charges the surface of the photoconductor by discharging to form an electrostatic latent image by exposing the charged photoconductor surface. A toner is supplied to the electrostatic latent image to make it visible, and the visible image formed on the surface of the photoreceptor is transferred onto the surface of the transfer paper, and then fixed and discharged. Since the untransferred toner remains on the surface of the photoconductor after the transfer of the visible image, the photoconductor surface is cleaned by a cleaning device so that they do not adversely affect the next image formation. Be prepared for the process. As a cleaning device, a cleaning blade made of an elastic material such as rubber or a fur brush in which synthetic resin fibers are formed in a brush shape is rubbed against the surface of the photoreceptor to remove deposits such as untransferred toner. Known.

  By the way, when fine toner or toner melted by heat, pressure, etc. adheres to the photoreceptor or intermediate transfer body, the transfer residual toner cannot be completely removed by the blade alone, and the filming layer gradually becomes the photoreceptor. In addition, there is a problem that the transfer performance is deteriorated due to the formation on the surface of the intermediate transfer member and the image quality is deteriorated. Further, when a filming layer is formed on the surface of the photosensitive member or intermediate transfer member, the friction coefficient between the blade and the image carrier increases, and the blade is likely to be caught.

JP-A-9-81005 JP 2000-338819 A

  In order to solve such a problem, as described in Patent Document 1, it has been proposed to apply a lubricity-imparting agent to a photosensitive member or an intermediate transfer member. However, the apparatus of Patent Document 1 has a problem that the lubricity imparting agent shaved by the grinding roller is transferred to the fur brush and applied to the photoconductor and the like, which requires a grinding roller, resulting in an increase in cost. Further, there is a problem that the pressure of the spring changes with the wear of the lubricity imparting agent, and the amount of the lubricity imparting agent applied cannot be made constant.

  Further, in the apparatus of Patent Document 2, the lubricity-imparting agent has a two-layer structure and the application is stabilized. However, the lubricity-imparting agent having a two-layer structure increases the cost. Further, there is a problem that the pressure of the spring changes with the wear of the lubricity imparting agent, and the amount of the lubricity imparting agent applied cannot be made constant.

  The present invention has been made in view of the above problems, and the problem is that the cleaning with a fur brush can be stabilized over a long period of time with a simple configuration, and lubricity can be achieved without using a grinding roller. An object of the present invention is to provide a cleaning device, an image forming apparatus, and a process cartridge capable of stably applying an imparting agent to an image carrier.

In order to solve the above-mentioned problems, the present invention provides a fur brush that removes residues such as transfer residual toner on an image carrier and scrapes a solid lubricity imparting material and applies a lubricant on the image carrier. And the fur brush has a length extending in the longitudinal direction between an image writing area in which an image of the image carrier is written and a non-image area in which an image is not written. The brush bristle length located in the image writing area in the direction is shorter than the brush bristle leg length located in the non-image area, and the cutting force of the solid lubricity imparting material by the brush hair in the image writing area, The present invention proposes a cleaning device that is higher than the non-image area .

  Furthermore, in the cleaning device of the present invention, the fur brush is effective when the difference in the length of the brush bristle length in the image area and the non-image area is 0.05 mm to 0.5 mm.

Furthermore, in the cleaning apparatus of the present invention, it is effective to use polyester fibers as the fur brush hair material.
Furthermore, in the cleaning device of the present invention, it is effective that the polyester fiber that is the fur brush hair material and the base fabric on which the fibers are sewn are insulating materials.

  Furthermore, in the cleaning device of the present invention, the fur brush is effective when the adhesive for preventing the sewn polyester fibers from being unwound is an insulating material.

  Furthermore, in the cleaning apparatus of the present invention, it is effective to provide a solid state lubricity imparting agent pressed against the fur brush by a spring or its own weight.

In order to solve the above-mentioned problems, the present invention provides an image forming apparatus for forming an image with powder toner on an image carrier, wherein the toner remaining after the image is transferred to a transfer body is defined in claims 1 to 6. The image forming apparatus is characterized in that the image forming apparatus is removed by the cleaning apparatus described in any one of the above.

  In the image forming apparatus of the present invention, the toner has a weight average particle diameter of 3 to 8 μm and a ratio (D4 / D1) of the weight average particle diameter (D4) to the number average particle diameter (D1) is 1. It is effective when it is in the range of 00 to 1.40.

  Furthermore, in the image forming apparatus of the present invention, the toner is effective when the shape factor SF-1 is in the range of 100 to 180 and the shape factor SF-2 is in the range of 100 to 180.

Furthermore, in the image forming apparatus of the present invention, the toner is obtained by externally adding fine particles having an average primary particle size of 50 to 500 nm and a bulk density of 0.3 g / cm ³ or more to the surface of the toner base particles. It is effective to use toner.

  Furthermore, in the image forming apparatus of the present invention, the toner is composed of at least a binder resin, a colorant, and a release agent, and has a glass transition temperature of 45 to 65 ° C. and an outflow start temperature of 90 to 115 ° C. And effective.

  Furthermore, in the image forming apparatus of the present invention, the toner includes a toner material liquid in which at least a polyester prepolymer having a functional group containing a nitrogen atom, polyester, a colorant, and a release agent are dispersed in an organic solvent. The toner obtained by crosslinking and / or elongation reaction in an aqueous medium is effective.

In order to solve the above problems, the present invention includes an image carrier that carries a latent image and a cleaning unit that cleans the surface of the image carrier after transfer, and is integrally supported, and the image forming apparatus main body In the process cartridge formed detachably, the cleaning means is the cleaning device according to any one of claims 1 to 6 , and proposes a process cartridge.

  According to the present invention, it is possible to provide a cleaning device, an image forming apparatus, and a process cartridge which can be stabilized over a long period of time by a fur brush cleaning and application of a lubricity imparting agent, which are simple and inexpensive.

  The best mode for carrying out the present invention will be described below with reference to the drawings. The following description is an example of the best mode of the present invention, and it is easy for a person skilled in the art to make other embodiments within the scope of the claims by making changes and modifications within the scope of the claims. However, this does not limit the scope of the claims.

  FIG. 1 is a schematic diagram showing a configuration of an image forming apparatus according to an embodiment of the present invention. FIG. 1 is an overall configuration diagram showing an example in which the present invention is applied to a full-color small printer. In an image forming apparatus main body (hereinafter, simply referred to as “apparatus main body”) 1, image forming units 2 A, 2 B, 2 C, and 2 D having four photosensitive members as image carriers are connected to the apparatus main body 1. Are detachably attached. A transfer device 3 in which a transfer belt 31 is rotatably mounted in a direction indicated by an arrow A between a plurality of rollers is disposed in the approximate center of the device body 1.

  The photosensitive member 5 provided in each of the image forming units 2A, 2B, 2C, and 2D is disposed so as to contact the upper surface of the transfer belt 31. Then, developing devices 10A, 10B, 10C, and 10D having different toner colors are arranged corresponding to the image forming units 2A, 2B, 2C, and 2D, respectively.

  The image forming units 2A, 2B, 2C, and 2D are units having the same configuration, the image forming unit 2A forms an image corresponding to magenta, and the image forming unit 2B forms an image corresponding to cyan. The image forming unit 2C forms an image corresponding to the yellow color, and the image forming unit 2D forms an image corresponding to the black color.

  A writing unit 6 is disposed above the image forming units 2A, 2B, 2C, and 2D, and a duplex unit 7 is disposed below the transfer belt 31. This small printer is equipped with a reversing unit 8 on the left side of the apparatus main body 1 for reversing and ejecting the transfer paper after image formation or transporting it to the duplex unit 7.

  The exposure device 6 is arranged in four laser diode (LD) light sources prepared for each color, a set of polygon scanners composed of six polygon mirrors and a polygon motor, and the route of each light source. It is composed of a lens such as an fθ lens or a long cylindrical lens, or a mirror. Laser light emitted from the laser diode is deflected and scanned by a polygon scanner and irradiated onto the photosensitive member 5.

  The duplex unit 7 includes a pair of conveyance guide plates 45a and 45b and a pair of (four sets in this example) conveyance rollers 46. In the double-sided image formation mode in which an image is formed on both sides of a transfer sheet, The transfer sheet having an image formed on one side, conveyed to the reversal conveyance path 54 of the reversing unit 8 and switched back is received and conveyed toward the paper feeding unit.

  The reversing unit 8 includes a plurality of paired transport rollers 46 and a plurality of paired transport guide plates 45. As described above, the reversing unit 8 reverses the transfer paper when forming a double-sided image to the double-sided unit 7. It carries out functions such as unloading, discharging the image-formed transfer paper out of the machine in the same orientation, or inverting the front and back and discharging it out of the machine. Separating sheet feeding units 55 and 56 for separating and feeding the transfer sheets one by one are provided in the sheet feeding unit in which the sheet feeding cassettes 11 and 12 are provided.

  Between the transfer belt 31 and the reversing unit 8, there is provided a fixing device 9 for fixing the image of the transfer paper onto which the image has been transferred. A reverse discharge path 20 is formed on the downstream side of the fixing device 9 in the transfer sheet conveyance direction, and the transfer sheet conveyed there can be discharged onto a discharge tray 26 by a discharge roller pair 25. .

  In addition, in the lower part of the apparatus main body 1, paper feeding cassettes 11 and 12 that can store transfer papers of different sizes in two upper and lower stages are arranged. Further, a manual feed tray 13 is provided on the right side surface of the apparatus main body 1 so as to be openable and closable in the direction indicated by the arrow B, and the manual feed tray 13 is opened so that manual feeding can be performed therefrom.

  Next, the operation of the image forming apparatus in image formation will be described. When the image forming operation is started, each photoconductor rotates in the clockwise direction in FIG. Then, the surface of each photoconductor 5 is uniformly charged by the charging roller 141. Then, laser light corresponding to a magenta image is applied to the photoconductor 5 of the image forming unit 2 by the exposure device 6, and laser light corresponding to a cyan image is applied to the photoconductor 5 of the image forming unit 2B. The 2C photoconductor 5 is irradiated with a laser beam corresponding to a yellow image, and the photoconductor 5 of the image forming unit 2D is irradiated with a laser beam corresponding to a black image, and a latent image corresponding to each color image data. Are formed respectively. Each latent image reaches the position of the developing devices 10A, 10B, 10C, and 10D by the rotation of the photosensitive member 5, and is developed there by toners of magenta, cyan, yellow, and black. Become.

  On the other hand, the transfer paper is fed from the paper feed cassettes 11 and 12 by the separation paper feed unit, and the toner formed on each photoconductor 5 by the registration roller pair 59 provided immediately before the transfer belt 31. It is conveyed at the same timing as the image. The transfer paper is charged with a positive polarity by a paper suction roller 58 disposed near the entrance of the transfer belt 31, and is thereby electrostatically attracted to the surface of the transfer belt 31. The transfer paper is conveyed while being adsorbed to the transfer belt 31, and magenta, cyan, yellow, and black toner images are sequentially transferred to form a four-color superimposed full-color toner image. . The transfer paper is heated and pressed by the fixing device 9 to melt and fix the toner image, and then passes through a paper discharge system corresponding to the designated mode to the paper discharge tray 26 at the top of the apparatus main body 1. When the paper is reversed, discharged straight from the fixing device 9 and straightly discharged through the reversing unit 8, or when the double-sided image forming mode is selected, the reversing conveyance path in the reversing unit 8 is set. After being sent in, it is switched back and conveyed to the duplex unit 7, and is fed again from there. After the image is formed on the back surface by the image forming units 2 A, 2 B, 2 C, and 2 D, it is discharged.

  On the other hand, the photosensitive member 5 separated from the transfer belt 31 continues to rotate and the lubricant brushed off from the lubricant imparting agent (hereinafter also referred to as “lubricant molding”) 162 in a solid state by a fur brush 161 described later. Is applied to the photoreceptor 5.

  In the subsequent image formation, the above-described image forming process is repeated. However, the lubricant film formed on the photoconductor 5 is very thin, so that charging by the charging device 14 is not hindered. Thereafter, the toner image developed again on the photosensitive member 5 is transferred to the transfer paper adsorbed on the transfer belt 31.

  The developing devices 10A, 10B, 10C, and 10D include a developing roller that faces the photoreceptor 5, a screw that conveys and stirs the developer, a toner concentration sensor, and the like. The developing roller is composed of an outer rotatable sleeve and an inner magnet. In accordance with the output of the toner density sensor, toner is supplied from the toner supply device. In this embodiment, a two-component developer composed of toner and carrier is used as the developer. Details of the toner and carrier used will be described later.

  FIG. 2 is a schematic diagram showing the configuration of the process cartridge 21 of the present embodiment. A process cartridge 21 shown in FIG. 2 includes a photosensitive member 5 on which an electrostatic latent image is formed, a charging device 14 that charges the surface of the photosensitive member 5, and a cleaning device 15 that cleans the surface of the photosensitive member 5. It is composed of The process cartridge 21 of the present embodiment includes the photosensitive member 5, the charging device 14, and the cleaning device 15. However, if the process cartridge of the present invention includes the photosensitive member 5 and the cleaning device 15, charging, developing, and the like. Discarding other toner image forming elements is optional

  The photoconductor 5 can be made of an amorphous metal having photoconductivity, an amorphous metal such as amorphous selenium, or an organic compound such as a bisazo pigment or a phthalocyanine pigment. Considering the environment and post-treatment after use, it is preferable to use an organic compound.

  The charging device 14 may be any one of a corona method, a roller method, a brush method, and a blade method, and here, the roller charging device 14 is shown. The charging device 14 includes a charging roller 141, a charging roller cleaning brush 142 in contact with the charging roller 141 for cleaning, and a power supply (not shown) connected to the charging roller 141. A high voltage is applied to the charging roller 141 to uniformly charge the surface of the photoreceptor 5.

  The cleaning device 15 is driven to rotate counterclockwise by a driving device (not shown), thereby removing the transfer residual toner, and applying the lubricant to the photoconductor, the fur brush 161, and the transfer residual toner attached to the fur brush 161. Flickering 158 for flaking off, a lubricant molded body 162 that is a solid-state lubricity imparting agent, a lubricant molded body pressing spring 163 that presses the lubricant molded body 162 against the fur brush 161 with a predetermined pressure, and the surface of the photoreceptor 5 A cleaning blade 151 that removes the transfer residual toner and uniformly extends the lubricant, a support 154 that supports the cleaning blade 151, and a blade pressure spring 152 that adjusts the contact pressure of the cleaning blade 151 are provided.

  The contact method of the cleaning blade 151 may be either a counter method or a trailing method. In particular, a counter system is preferable. This is because even if the contact pressure against the photoconductor 5 is small, the cleaning property is high and the photoconductor 5 is less worn.

  In addition, the cleaning blade 151 in the cleaning device of the present invention is preferably fixed or integrally formed with the support plate 154 in order to maintain a uniform contact angle and contact pressure.

  The material for forming the cleaning blade 151 is not particularly limited as long as it is urethane rubber. Among these, in consideration of the molding process of the cleaning blade 151, a liquid thermosetting material is used. Further, as a production method, a prepolymer method, a one-shot method, and a pseudo one-shot method which is an intermediate between them are used. As the liquid forming material, for example, a material mainly composed of a urethane rubber prepolymer and a curing agent is used. The prepolymer for urethane rubber is obtained by partially polymerizing polyisocyanate and polyol.

  Examples of the lubricant of the molded lubricant 162 include lead oleate, zinc oleate, copper oleate, zinc stearate, cobalt stearate, iron stearate, copper stearate, zinc palmitate, copper palmitate, linolene. Fatty acid metal salts such as zinc acid, polytetrafluoroethylene, polychlorotrifluoroethylene, polyvinylidene fluoride, polytrifluorochloroethylene, dichlorodifluoroethylene, tetrafluoroethylene-ethylene copolymer, tetrafluoroethylene-oxafluoropropylene Fluorine-based resins such as copolymers are listed. In particular, a metal stearate having a large effect of reducing the friction of the photoreceptor 5 and further zinc stearate are more preferable. As the molded lubricant 162, a product obtained by melting and solidifying a fatty acid metal salt such as zinc stearate into a rod shape can be used.

  The fur brush 161 includes innumerable bristles and rotates in the same direction as the rotation direction of the photoconductor 5 at the contact portion with the photoconductor 5. The pressure spring 163 is urged against the fur brush 161 so that almost all of the lubricant molded body 162 can be used up. Since the lubricant molded body 162 is a consumable product, its thickness decreases with time. However, since the lubricant molded body 162 is pressurized by the pressure spring 163, the lubricant is scraped off by contact with the fur brush 161 at all times. Supply and apply to the photoreceptor 5. When adjusting the lubricant application amount, the application amount to the photosensitive member 5 can be adjusted by the weight of the lubricant molded body 162 itself or by the pressure spring 163. In this embodiment, the pressure spring 163 is pressed.

  FIG. 3 is a diagram illustrating a configuration of the fur brush according to the present embodiment. The fur brush 161 is made of an insulating polyester fiber and is sewn to the insulating base fabric 100. Furthermore, an insulating adhesive is applied to the sewn polyester fibers so that the sewn polyester fibers are not unwound. By making it insulative, the influence on the potential of the photoreceptor surface can be suppressed, and transfer residual toners having different polarities can be efficiently removed. The fur brush 161 is completed by winding the base fabric 100 sewed with the brush around the cored bar 110.

  By the way, the fur brush 161 has a higher ability to scrape the solid lubricant and has a higher ability to apply to the photoconductor 5 than a brush having a shorter bristle length. That is, the ability to reduce the friction coefficient of the photoconductor 5 is high. It is thought that this mechanism is considered to be high repulsive force against the pressing force from the solid lubricant when the bristle is short, and high cutting force to scrape the solid lubricant at the hair tip, while the long bristle is long Then, since the hair lies down against the pressing force from the solid lubricant, it is considered that the cutting force is weakened because it contacts the solid lubricant on the side of the hair instead of the hair tip.

  Therefore, in the embodiment shown in FIG. 4, the properties of the fur brush 161 are skillfully used, and the brush bristle length located in the image writing area A1 where the image of the photoconductor 5 is written and the non-image area B1 are located. The length of the brush bristle differs, and in the apparatus of this embodiment, the image writing area A1 is set to 2.8 mm, and the non-image area B1 is set to 3.1 mm. Note that the image writing area A1 and the non-image area B1 in FIG. 4 are areas in which the fur brush 161 is divided in the axial direction, so that the image writing area on the transfer paper and the image writing area A1 of the fur brush 161 have the same length. Although it is an area, the length of the non-image area of the transfer paper and the non-image area B1 of the fur brush 161 are different.

  With this setting, the untransferred toner is input to the cleaning blade 151 in the image writing area A1. Transfer residual toner is present at the contact position between the photosensitive member 5 and the cleaning blade 151, and the lubricant coating agent applied on the photosensitive member 5 is scraped off. A lubricity-imparting agent that has been scraped off with a brush is applied thereto to lower the coefficient of friction of the image carrier. On the other hand, in the non-image area B1, the transfer residual toner is not input to the cleaning blade 151, and the lubricity imparting agent applied on the photoreceptor 5 is difficult to be scraped off. If the same amount of lubricity-imparting agent as that in the image writing area A1 is newly supplied to the non-image area B1, the supply of the lubricant coating agent in the non-image area B1 becomes excessive as compared with the image writing area A1. As a result, a friction coefficient deviation occurs, and the cleaning performance is deteriorated. Further, in the non-image area B1, slipping of the additive in the toner due to overcoating increases, and an abnormal image due to contamination of the charging roller 141 may be generated.

  It has been experimentally known that when the length of the brush bristle is long, the amount of wear of the lubricity-imparting agent is reduced. Therefore, compared to the image writing area A1, the supply amount of the lubricating coating agent should be reduced in the non-image area B1. By increasing the length of the brush bristle foot, it is possible to prevent excessive supply and to prevent the occurrence of a friction coefficient deviation with respect to the longitudinal direction of the photoreceptor 5. Since the friction coefficient deviation is small, the influence on the cleaning blade 151 can be reduced, and the slipping of toner or the like can be suppressed, so that the occurrence of abnormal images due to contamination of the charging roller 141 can be prevented. In this embodiment, the difference in the length of the brush bristle foot between the image writing area A1 and the non-image area B1 of the fur brush 161 is 0.3 mm. However, the difference is 0.05 mm to 0.5 mm. It was generally good.

Next, the toner suitably used in the image forming apparatus of the present invention will be described.
In order to reproduce minute dots of 600 dpi or more, the toner preferably has a weight average particle diameter of 3 to 8 μm. In this range, since the toner particles have a sufficiently small particle size with respect to the minute latent image dots, the dot reproducibility is excellent.
When the weight average particle diameter (D4) is less than 3 μm, phenomena such as a decrease in transfer efficiency and a decrease in blade cleaning properties tend to occur.
When the weight average particle diameter (D4) exceeds 8 μm, it is difficult to suppress scattering of characters and lines.
The ratio (D4 / D1) of the weight average particle diameter (D4) to the number average particle diameter (D1) is preferably in the range of 1.00 to 1.40.
The closer (D4 / D1) is to 1.00, the sharper the particle size distribution. With such a toner having a small particle size and a narrow particle size distribution, the toner charge amount distribution is uniform, a high-quality image with little background fogging can be obtained, and the electrostatic transfer method has a high transfer rate. can do.

Next, a method for measuring the particle size distribution of toner particles will be described.
Examples of the measuring device for the particle size distribution of toner particles by the Coulter counter method include Coulter Counter TA-II and Coulter Multisizer II (both manufactured by Coulter). The measurement method is described below.

  First, 0.1 to 5 ml of a surfactant (preferably alkylbenzene sulfonate) is added as a dispersant to 100 to 150 ml of an aqueous electrolytic solution. Here, the electrolytic solution is a solution prepared by preparing a 1% NaCl aqueous solution using primary sodium chloride. For example, ISOTON-II (manufactured by Coulter) can be used. Here, 2 to 20 mg of a measurement sample is further added. The electrolytic solution in which the sample is suspended is subjected to a dispersion treatment with an ultrasonic disperser for about 1 to 3 minutes, and the measurement device is used to measure the weight and number of toner particles or toner using a 100 μm aperture as an aperture. Calculate weight distribution and number distribution. From the obtained distribution, the weight average particle diameter (D4) and the number average particle diameter (D1) of the toner can be obtained.

  As channels, 2.00 to less than 2.52 μm; 2.52 to less than 3.17 μm; 3.17 to less than 4.00 μm; 4.00 to less than 5.04 μm; 5.04 to less than 6.35 μm; 6 Less than 35 to 8.00 μm; less than 8.00 to less than 10.08 μm; less than 10.08 to less than 12.70 μm; less than 12.70 to less than 16.00 μm; less than 16.00 to less than 20.20 μm; Uses 13 channels of less than 40 μm; 25.40 to less than 32.00 μm; 32.00 to less than 40.30 μm, and targets particles having a particle size of 2.00 μm to less than 40.30 μm.

  The toner shape factor SF-1 is preferably in the range of 100 to 180, and the shape factor SF-2 is preferably in the range of 100 to 180. FIGS. 7A and 7B are diagrams schematically illustrating the shape of the toner in order to explain the shape factor SF-1 and the shape factor SF-2. The shape factor SF-1 indicates the ratio of the roundness of the toner shape and is represented by the following formula (1). This is a value obtained by dividing the square of the maximum length MXLNG of the shape formed by projecting the toner on a two-dimensional plane by the figure area AREA and multiplying by 100π / 4.

SF-1 = {(MXLNG) 2 / AREA} × (100π / 4) Formula (1)
When the value of SF-1 is 100, the shape of the toner becomes a true sphere, and becomes larger as the value of SF-1 increases.

  The shape factor SF-2 indicates the ratio of the unevenness of the toner shape, and is represented by the following formula (2). A value obtained by dividing the square of the perimeter PERI of the figure formed by projecting the toner onto the two-dimensional plane by the figure area AREA and multiplying by 100 / 4π.

SF-2 = {(PERI) 2 / AREA} × (100 / 4π) (2)
When the value of SF-2 is 100, there is no unevenness on the toner surface, and as the value of SF-2 increases, the unevenness of the toner surface becomes more prominent.

  Specifically, the shape factor is measured by taking a photograph of the toner with a scanning electron microscope (S-800: manufactured by Hitachi, Ltd.), introducing it into an image analyzer (LUSEX 3: manufactured by Nireco) and analyzing it. Calculated.

  When the shape of the toner is close to a spherical shape, the contact state between the toner and the toner or the toner and the photoconductor becomes a point contact, so that the adsorbing force between the toners becomes weak and the fluidity becomes high. The attraction force becomes weaker and the transfer rate becomes higher. If either of the shape factors SF-1 and SF-2 exceeds 180, the transfer rate is lowered, which is not preferable.

The toner of the present invention is a toner obtained by externally adding fine particles having an average primary particle size of 50 to 500 nm and a bulk density of 0.3 g / cm 3 or more to the surface of the base particles.
By using fine particles having an average primary particle size of 50 to 500 nm and a bulk density of 0.3 mg / cm 3 or more as an external additive, a small particle size toner having good cleaning properties and particularly high image quality is used. If this occurs, improvement in developability and transferability can be improved.

Hereinafter, the toner of the present invention will be described in detail. In the toner of the present invention, fine particles (hereinafter, simply referred to as fine particles) having an average primary particle diameter of 50 to 500 nm and a bulk density of 0.3 mg / cm ³ or more are adhered to the toner particle surface. In addition, although silica etc. are often used for a normal fluid improvement agent, for example, the average primary particle diameter of this silica is 10-30 nm normally, and a bulk density is 0.1-0.2 mg / cm < ³ >.
In the present invention, since fine particles having appropriate characteristics are present on the surface of the toner, an appropriate gap is formed between the toner particles and the object. Further, the fine particles have a very small contact area with the toner particles, the photoconductor, and the charge imparting member and are evenly contacted with each other, so that the effect of reducing the adhesive force is great and effective in improving the development / transfer efficiency. Furthermore, since it plays the role of a roller, it is difficult to be buried in toner particles even during cleaning under high stress (high load, high speed, etc.) between the cleaning blade and the photoconductor without wearing or damaging the photoconductor. Or, even if it is buried a little, it can be detached and returned, so that stable characteristics can be obtained over a long period of time. Further, the toner is moderately detached from the surface of the toner and accumulated at the tip of the cleaning blade, and the so-called dam effect has an effect of preventing a phenomenon that the toner passes from the blade. Since these characteristics have an effect of reducing the share received by the toner particles, the filming effect of the toner itself due to the low rheological component contained in the toner is exhibited for high-speed fixing (low energy fixing). In addition, when fine particles having an average primary particle size in the range of 50 to 500 μm are used, the excellent cleaning performance can be fully utilized, and since the particle size is extremely small, the powder fluidity of the toner is improved. There is no reduction. Further, although the details are not clear, even if the surface-treated fine particles are externally added to the toner or the carrier is contaminated, the degree of developer deterioration is small.
The average primary particle size (hereinafter referred to as the average particle size) of the fine particles is 50 to 500 nm, and particularly preferably 100 to 400 nm. If the thickness is less than 50 nm, the fine particles may be buried in the concave and convex portions on the toner surface to lower the role of the rollers. On the other hand, when the particle size is larger than 500 μm, when the fine particles are located between the blade and the surface of the photosensitive member, the order is the same level as the contact area of the toner itself, and the toner particles to be cleaned pass, that is, defective cleaning occurs. It becomes easy.

When the bulk density is less than 0.3 mg / cm ³ , although there is a contribution to the improvement of fluidity, the scattering property and adhesion of the toner and fine particles become high, so the effect as a toner and a roller, and accumulation in the cleaning unit. As a result, the so-called dam effect that prevents toner cleaning failure is reduced.

In the fine particles of the present invention, the inorganic compounds include SiO ₂ , TiO ₂ , Al ₂ O ₃ , MgO, CuO, ZnO, SnO ₂ , CeO ₂ , Fe ₂ O ₃ , BaO, CaO, K ₂ O, Na ₂ O. , ZrO ₂ , CaO · SiO ₂ , K ₂ O (TiO ₂ ) n, Al ₂ O ₃ · 2SiO ₂ , CaCO ₃ , MgCO ₃ , BaSO ₄ , MgSO ₄ , SrTiO _{3 and the} like, preferably , SiO ₂ , TiO ₂ , and Al ₂ O ₃ . In particular, these inorganic compounds may be hydrophobized with various coupling agents, hexamethyldisilazane, dimethyldichlorosilane, octyltrimethoxysilane, and the like.

  The organic compound fine particles may be thermoplastic resins or thermosetting resins, such as vinyl resins, polyurethane resins, epoxy resins, polyester resins, polyamide resins, polyimide resins, silicon resins, phenol resins, melamine resins, Examples include urea resins, aniline resins, ionomer resins, and polycarbonate resins. As the resin fine particles, two or more of the above resins may be used in combination. Of these, vinyl resins, polyurethane resins, epoxy resins, polyester resins, and combinations thereof are preferred because an aqueous dispersion of fine spherical resin particles is easily obtained.

  Specific examples of vinyl resins include polymers obtained by homopolymerization or copolymerization of vinyl monomers, such as styrene- (meth) acrylic acid ester copolymers, styrene-butadiene copolymers, (meth) acrylic acid. -Acrylic ester copolymer, styrene-acrylonitrile copolymer, styrene-maleic anhydride copolymer, styrene- (meth) acrylic acid copolymer, and the like.

  The bulk density of the fine particles was measured by the following method. Using a 100 ml graduated cylinder, fine particles were gradually added to make 100 ml. At that time, no vibration was applied. The bulk density was measured by the difference in weight before and after placing the fine particles of the graduated cylinder.

Bulk density (g / cm 3) = fine particle amount (g / 100 ml) ÷ 100
The fine particles of the present invention can be externally added and adhered to the toner surface by mechanically mixing and adhering the toner base particles and fine particles using various known mixing devices, or in the liquid phase. There is a method in which the base particles and the fine particles are uniformly dispersed with a surfactant or the like, and are dried after the adhesion treatment.

  Many toner characteristics related to toner fixing properties are known, and in particular, it is known that a ½ outflow temperature (softening point) is related. For the fixing device of the present invention, a ½ outflow temperature is known. (Softening point) No relationship was found in the fixability, and a good fixability was obtained by using a toner satisfying both characteristics of a glass transition temperature of 45 to 65 ° C. and an outflow start temperature of 90 to 115 ° C. It became clear that

  When the glass transition temperature is lower than 45 ° C., offset may occur during fixing. Conversely, when the glass transition temperature is higher than 65 ° C., sufficient fixing property cannot be obtained, and the image is easily peeled off from the transfer paper. There is. If the outflow start temperature is lower than 90 ° C, offset may occur during fixing. Conversely, if it is higher than 115 ° C, sufficient fixability cannot be obtained, and the image tends to peel off from the transfer paper. There is.

Glass transition point (Tg)
A method for measuring Tg will be outlined. As an apparatus for measuring Tg, a TG-DSC system TAS-100 manufactured by Rigaku Corporation was used.

  First, about 10 mg of a sample is placed in an aluminum sample container, which is placed on a holder unit and set in an electric furnace. First, after heating from room temperature to 150 ° C. at a temperature rising rate of 10 ° C./min, the sample was allowed to stand at 150 ° C. for 10 min, the sample was cooled to room temperature and left for 10 min, and the temperature rising rate was again increased to 150 ° C. under a nitrogen atmosphere. DSC measurement was performed by heating at min. Tg was calculated from the tangent of the endothermic curve near the Tg and the base line using the analysis system in the TAS-100 system.

Outflow start temperature The outflow start temperature of the toner can be measured using a flow tester.
An example of a flow tester is an elevated flow tester CFT500D manufactured by Shimadzu Corporation. The flow curve of this flow tester becomes the data shown in FIGS. 8A and 8B, from which each temperature can be read. In the figure, Tfb is the outflow start temperature, and the melting temperature in the 1/2 method is the T1 / 2 temperature.

<< Measurement Conditions >> Load: 5 kg / cm ² , Temperature rising rate: 3.0 ° C./min,
Die diameter: 1.00 mm, die length: 10.0 mm
As the binder resin used in the toner of the present invention, those having the following composition can be used as long as the characteristics of the toner of the present invention are satisfied.
For example, homopolymers of styrene such as polyester, polystyrene, poly p-chlorostyrene, polyvinyltoluene and the like; and styrene-p-chlorostyrene copolymers, styrene-propylene copolymers, styrene-vinyltoluene copolymers. Styrene-vinyl naphthalene copolymer, styrene-methyl acrylate copolymer, 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 ether copolymer, Styrene-vinyl ethyl acetate Ter copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-acrylonitrile-indene copolymer, styrene-maleic acid copolymer, styrene-maleic acid ester Examples thereof include styrene copolymers such as copolymers.

  Also, the following resins can be mixed and used. Polymethyl methacrylate, polybutyl methacrylate, polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, polyurethane, polyamide, epoxy resin, polyvinyl butyral, polyacrylic resin, rosin, modified rosin, terpene resin, phenol resin, aliphatic or Examples thereof include alicyclic hydrocarbon resins, aromatic petroleum resins, chlorinated paraffin, and paraffin wax.

  Among these, a polyester resin is particularly preferable in order to obtain sufficient fixability. The polyester resin is obtained by condensation polymerization of alcohol and carboxylic acid, and the alcohol used is polyethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butane. Diols such as diol, neopentyl glycol, 1,4-butenediol, 1,4-bis (hydroxymethyl) cyclohexane, bisphenol A, hydrogenated bisphenol A, polyexethylenated bisphenol A, polyoxypropylenated bisphenol A, etc. And a divalent alcohol simple substance obtained by substituting these with a saturated or unsaturated hydrocarbon group having 3 to 22 carbon atoms, and other divalent alcohol simple substance.

  Examples of the carboxylic acid used to obtain the polyester resin include maleic acid, fumaric acid, mesaconic acid, citraconic acid, itaconic acid, glutaconic acid, phthalic acid, isophthalic acid, terephthalic acid, cyclohexanedicarboxylic acid, succinic acid, Adipic acid, sebacic acid, malonic acid, divalent organic acid monomers in which these are substituted with a saturated or unsaturated hydrocarbon group having 3 to 22 carbon atoms, acid anhydrides thereof, lower alkyl esters and linolenic acid Dimers and other divalent organic acid monomers can be mentioned.

  In order to obtain a polyester resin to be used as a binder resin, it is also preferable to use not only a polymer with only the above bifunctional monomer but also a polymer containing a component with a trifunctional or higher polyfunctional monomer. It is. Examples of the polyhydric alcohol monomer having three or more valences that are such polyfunctional monomers include sorbitol, 1,2,3,6-hexanetetrol, 1,4-sarbitane, pentaesitol, dipenta. Esitol, tripentaerythritol, sucrose, 1,2,4-butanetriol, 1,2,5-pentanetriol, glycerol, 2-methylpropanetriol, 2-methyl-1,2,4-butanetriol , Trimethylolethane, trimethylolpropane, 1.3.5-trihydroxymethylbenzene, and others.

  Examples of the trivalent or higher polyvalent carboxylic acid monomer include 1,2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid, 1,2,4-cyclohexanetricarboxylic acid, 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 -Methylenecarboxypropane, tetra (methylenecarboxyl) methane, 1,2,7,8-octanetetracarboxylic acid, embol trimer acid, acid anhydrides thereof, and the like.

  The toner of the present invention may contain a release agent for the purpose of improving the releasability of the toner on the surface of the fixing belt at the time of fixing. As the release agent, all known ones can be used, and in particular, defree fatty acid type carnauba wax, montan wax, oxidized rice wax, and ester wax can be used alone or in combination. The carnauba wax is preferably a microcrystalline one, having an acid value of 5 or less and a particle size of 1 μm or less when dispersed in a toner binder. The montan wax generally refers to a montan wax refined from minerals, and like a carnauba wax, it is microcrystalline and preferably has an acid value of 5 to 14. The oxidized rice wax is obtained by air-oxidizing rice bran wax, and the acid value is preferably 10-30. When the acid value of each wax is less than the respective range, the low temperature fixing temperature rises and the low temperature fixing becomes insufficient. On the contrary, when the acid value exceeds each range, the cold offset temperature rises and the low-temperature fixing becomes insufficient. The added amount of the wax is 1 to 15 parts by weight, preferably 3 to 10 parts by weight with respect to 100 parts by weight of the binder resin. If it is less than 1 part by weight, the releasing effect is thin and the desired effect is difficult to obtain. On the other hand, when the amount exceeds 15 parts by weight, problems such as significant spent on the carrier occur.

  Further, for the purpose of imparting charge to the toner, a charge control agent can be contained. Any conventionally known charge control agent can be used. Examples of positive charge control agents include nigrosine, basic dyes, lake dyes of basic dyes, quaternary ammonium salt compounds, etc., and examples of negative charge control agents include metal salts of monoazo dyes, salicylic acid, naphthoic acid, dyes, and the like. Examples include carboxylic acid metal complexes and the like. The amount of the polarity control agent used is determined by the toner production method including the type of binder resin, the presence or absence of additives used as necessary, and the dispersion method, and is not limited uniquely. Is used in an amount of 0.01 to 8 parts by weight, preferably 0.1 to 2 parts by weight, based on 100 parts by weight of the binder resin. If it is less than 0.01 part by weight, the effect is small with respect to the fluctuation of the charge amount Q / M at the time of environmental change.

  Further, as the metal-containing monoazo dye to be used, a chromium-containing monoazo dye, a cobalt-containing monoazo dye, and an iron-containing monoazo dye can be used alone or in combination. By adding these, the rising of the charge amount Q / M in the developer (time until saturation) becomes more excellent. The amount used is determined by the toner production method including the type of binder resin, the presence or absence of additives used as necessary, and the dispersion method as in the case of the polar control agent, and is uniquely limited. However, it is used in the range of 0.1 to 10 parts by weight, preferably 1 to 7 parts by weight with respect to 100 parts by weight of the binder resin. If the amount is less than 0.1 parts by weight, the effect is small, and if the amount exceeds 10 parts by weight, defects such as a decrease in the saturation level of the charge amount occur.

  In addition, it is particularly preferable to use a metal salt of a salicylic acid derivative for the color toner, but if necessary, a transparent or white substance that does not impair the color tone of the color toner is added to stabilize the charging property of the toner. Can be granted. Specifically, organic boron salts, fluorine-containing quaternary ammonium salts, calixarene compounds and the like are used, but are not limited thereto.

  Furthermore, the toner of the present invention further contains a magnetic material and can be used as a magnetic toner. Examples of the magnetic material contained in the magnetic toner of the present invention include iron oxides such as magnetite, hematite, and ferrite, metals such as iron, cobalt, and nickel, or aluminum, cobalt, copper, lead, magnesium, tin, and zinc of these metals. And alloys of metals such as antimony, beryllium, bismuth, cadmium, calcium, manganese, selenium, titanium, tungsten, vanadium, and mixtures thereof.

  These ferromagnetic materials preferably have an average particle size of about 0.1 to 2 μm. The amount of the ferromagnetic material to be contained in the toner is about 20 to 200 parts by weight, particularly preferably 100 parts by weight of the resin component, with respect to 100 parts by weight of the resin component. 40 to 150 parts by weight per part.

  As the colorant, all known colorants can be used. As the black colorant, for example, carbon black, aniline black, furnace black, lamp black and the like can be used. Examples of cyan colorants include phthalocyanine blue, methylene blue, Victoria blue, methyl violet, aniline blue, and ultramarine blue. As the magenta colorant, for example, rhodamine 6G lake, dimethylquinacridone, watching red, rose bengal, rhodamine B, alizarin lake and the like can be used. Examples of yellow colorants include chrome yellow, benzidine yellow, hansa yellow, naphthol yellow, molybdenum orange, quinoline yellow, and tartrazine. As the colorant used in the toner of the present invention, dyes and pigments capable of obtaining toners of yellow, magenta, cyan and black colors can be used. For example, carbon black, lamp black, ultramarine, aniline blue, phthalocyanine blue, phthalocyanine green, Hansa Yellow G, Rogmin 6G, lake, chalcoil blue, chrome yellow, quinacridone, benzidine yellow, rose bengal, triallylmethane dye, etc. Any conventionally known dyes and pigments such as dyes and pigments can be used alone or in combination.

In addition, as an external additive, for the purpose of improving the fluidity of the toner, hydrophobic silica,
Titanium oxide, alumina, and the like, and fatty acid metal salts, polyvinylidene fluoride, and the like may be added as necessary.

  Further, when the toner of the present invention is used as a two-component developer, all known carriers can be used. For example, magnetic powder such as iron powder, ferrite powder, nickel powder, glass, and the like. Examples thereof include beads and the like, and those whose surfaces are treated with a resin or the like.

  Examples of the resin powder that can be coated on the carrier in the present invention include a styrene-acrylic copolymer, a silicone resin, a maleic acid resin, a fluorine resin, and a polyester resin epoxy resin. In the case of a styrene-acrylic copolymer, those having a styrene content of 30 to 90% by weight are preferred. In this case, if the styrene content is less than 30% by weight, the developing characteristics are low, and if it exceeds 90% by weight, the coating film becomes hard and easily peeled, and the life of the carrier is shortened.

Moreover, the resin coating of the carrier in the present invention may contain an adhesion-imparting agent, a curing agent, a lubricant, a conductive material, a charge control agent and the like in addition to the resin.
In the present invention, the carrier core particles coated with the silicone resin may be those conventionally known, for example, ferromagnetic metals such as iron, cobalt and nickel; alloys and compounds such as magnetite, hematite and ferrite; and glass beads. It is done. The average particle diameter of these core particles is usually 10 to 1000 μm, preferably 30 to 500 μm. In addition, the usage-amount of a silicone resin is 1 to 10 weight% normally with respect to a carrier core particle.

  The silicone resin used in the present invention may be any conventionally known silicone resin. For example, commercially available KR261, KR271, KR271, KR272, KR275, KR280, KR282, KR285 manufactured by Shin-Etsu Silicone. , KR251, KR155, KR220, KR201, KR204, KR205, KR206, SA-4, ES1001, ES1001N, ES1002T, KR3093, SR2100, SR2101, SR2107, SR2110, SR2108, SR2109, SR2115, SR2115, SR2400, SR2410 SR2411, SH805, SH806A, SH840, etc. are used.

As a method for forming the silicone resin layer, a silicone resin may be applied to the surface of the carrier core particles by a spraying method, a dipping method, or the like, as in the past.
The toner suitably used in the image forming apparatus of the present invention includes a toner material liquid in which at least a polyester prepolymer having a functional group containing a nitrogen atom, polyester, a colorant, and a release agent are dispersed in an organic solvent A toner obtained by crosslinking and / or elongation reaction in an aqueous solvent. Hereinafter, the constituent material and the manufacturing method of the toner will be described.

(polyester)
The polyester is obtained by a polycondensation reaction between a polyhydric alcohol compound and a polycarboxylic acid compound.

  Examples of the polyhydric alcohol compound (PO) include a dihydric alcohol (DIO) and a trihydric or higher polyhydric alcohol (TO). (DIO) alone or a mixture of (DIO) and a small amount of (TO) preferable. Examples of the dihydric alcohol (DIO) include alkylene glycol (ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,6-hexanediol, etc.); alkylene ether glycol (diethylene glycol) , Triethylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene ether glycol, etc.); alicyclic diols (1,4-cyclohexanedimethanol, hydrogenated bisphenol A, etc.); bisphenols (bisphenol A, bisphenol) F, bisphenol S, etc.); alkylene oxide (ethylene oxide, propylene oxide, butylene oxide, etc.) adduct of the above alicyclic diol; Alkylene oxide bisphenol (ethylene oxide, propylene oxide, butylene oxide, etc.), etc. adducts. Among these, preferred are alkylene glycols having 2 to 12 carbon atoms and alkylene oxide adducts of bisphenols, and particularly preferred are alkylene oxide adducts of bisphenols and alkylene glycols having 2 to 12 carbon atoms. It is a combined use. The trihydric or higher polyhydric alcohol (TO) includes 3 to 8 or higher polyhydric aliphatic alcohols (glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, sorbitol, etc.); trihydric or higher phenols (Trisphenol PA, phenol novolak, cresol novolak, etc.); and alkylene oxide adducts of the above trivalent or higher polyphenols.

Examples of the polyvalent carboxylic acid (PC) include divalent carboxylic acid (DIC) and trivalent or higher polyvalent carboxylic acid (TC). (DIC) alone and (DIC) and a small amount of (TC) Mixtures are preferred. Divalent carboxylic acids (DIC) include alkylene dicarboxylic acids (succinic acid, adipic acid, sebacic acid, etc.); alkenylene dicarboxylic acids (maleic acid, fumaric acid, etc.); aromatic dicarboxylic acids (phthalic acid, isophthalic acid, terephthalic acid) And naphthalenedicarboxylic acid). Of these, preferred are alkenylene dicarboxylic acids having 4 to 20 carbon atoms and aromatic dicarboxylic acids having 8 to 20 carbon atoms. Examples of the trivalent or higher polyvalent carboxylic acid (TC) include aromatic polycarboxylic acids having 9 to 20 carbon atoms (such as trimellitic acid and pyromellitic acid). In addition, as polyhydric carboxylic acid (PC), you may make it react with polyhydric alcohol (PO) using the above-mentioned acid anhydride or lower alkyl ester (Methyl ester, ethyl ester, isopropyl ester, etc.).

  The ratio of the polyhydric alcohol (PO) to the polycarboxylic acid (PC) is usually 2/1 to 1/1, preferably as the equivalent ratio [OH] / [COOH] of the hydroxyl group [OH] and the carboxyl group [COOH]. Is 1.5 / 1 to 1/1, more preferably 1.3 / 1 to 1.02 / 1.

  The polycondensation reaction between a polyhydric alcohol (PO) and a polycarboxylic acid (PC) is carried out in the presence of a known esterification catalyst such as tetrabutoxytitanate or dibutyltin oxide, and heated to 150 to 280 ° C. while reducing the pressure as necessary. The produced water is distilled off to obtain a polyester having a hydroxyl group. The hydroxyl value of the polyester is preferably 5 or more, and the acid value of the polyester is usually 1 to 30, preferably 5 to 20. By giving an acid value, it tends to be negatively charged, and furthermore, when fixing to a recording paper, the affinity between the recording paper and the toner is good and the low-temperature fixability is improved. However, when the acid value exceeds 30, there is a tendency to deteriorate with respect to the stability of charging, particularly environmental fluctuation.

  The weight average molecular weight is 10,000 to 400,000, preferably 20,000 to 200,000. A weight average molecular weight of less than 10,000 is not preferable because offset resistance deteriorates. On the other hand, if it exceeds 400,000, the low-temperature fixability is deteriorated.

  In addition to the unmodified polyester obtained by the above polycondensation reaction, the polyester preferably contains a urea-modified polyester. The urea-modified polyester is obtained by reacting a terminal carboxyl group or hydroxyl group of the polyester obtained by the above polycondensation reaction with a polyvalent isocyanate compound (PIC) to obtain a polyester prepolymer (A) having an isocyanate group. It is obtained by cross-linking and / or extending the molecular chain by the reaction of the amine with amines.

  Examples of the polyvalent isocyanate compound (PIC) include aliphatic polyisocyanates (tetramethylene diisocyanate, hexamethylene diisocyanate, 2,6-diisocyanatomethylcaproate, etc.); alicyclic polyisocyanates (isophorone diisocyanate, cyclohexylmethane diisocyanate, etc.) ); Aromatic diisocyanates (tolylene diisocyanate, diphenylmethane diisocyanate, etc.); araliphatic diisocyanates (α, α, α ′, α′-tetramethylxylylene diisocyanate, etc.); isocyanates; phenol derivatives, oximes, polyisocyanates; Those blocked with caprolactam or the like; and combinations of two or more of these.

  The ratio of the polyvalent isocyanate compound (PIC) is usually 5/1 to 1/1, preferably as an equivalent ratio [NCO] / [OH] of the isocyanate group [NCO] and the hydroxyl group [OH] of the polyester having a hydroxyl group. 4/1 to 1.2 / 1, more preferably 2.5 / 1 to 1.5 / 1. When [NCO] / [OH] exceeds 5, low-temperature fixability deteriorates. When the molar ratio of [NCO] is less than 1, when a urea-modified polyester is used, the urea content in the ester is lowered and hot offset resistance is deteriorated.

  The content of the polyvalent isocyanate compound (PIC) component in the polyester prepolymer (A) having an isocyanate group is usually 0.5 to 40 wt%, preferably 1 to 30 wt%, more preferably 2 to 20 wt%. . If it is less than 0.5 wt%, the hot offset resistance deteriorates, and it is disadvantageous in terms of both heat-resistant storage stability and low-temperature fixability. On the other hand, if it exceeds 40 wt%, the low-temperature fixability deteriorates.

  The number of isocyanate groups contained per molecule in the polyester prepolymer (A) having an isocyanate group is usually 1 or more, preferably 1.5 to 3 on average, more preferably 1.8 to 2 on average. Five. If it is less than 1 per molecule, the molecular weight of the urea-modified polyester will be low, and the hot offset resistance will deteriorate.

  Next, as amines (B) to be reacted with the polyester prepolymer (A), a divalent amine compound (B1), a trivalent or higher polyvalent amine compound (B2), an amino alcohol (B3), an amino mercaptan (B4) ), Amino acid (B5), and amino acids B1 to B5 blocked (B6).

Examples of the divalent amine compound (B1) include aromatic diamines (phenylenediamine, diethyltoluenediamine, 4,4′-diaminodiphenylmethane, etc.); alicyclic diamines (4,4′-diamino-3,3′-dimethyldicyclohexyl). Methane, diamine cyclohexane, isophorone diamine, etc.); and aliphatic diamines (ethylene diamine, tetramethylene diamine, hexamethylene diamine, etc.)
Etc.

  Examples of the trivalent or higher polyvalent amine compound (B2) include diethylenetriamine and triethylenetetramine. Examples of amino alcohol (B3) include ethanolamine and hydroxyethylaniline. Examples of amino mercaptan (B4) include aminoethyl mercaptan and aminopropyl mercaptan.

  Examples of the amino acid (B5) include aminopropionic acid and aminocaproic acid. Examples of the compound (B6) obtained by blocking the amino group of B1 to B5 include ketimine compounds and oxazolidine compounds obtained from the amines of B1 to B5 and ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.). Among these amines (B), preferred are B1 and a mixture of B1 and a small amount of B2.

The ratio of amines (B) is equivalent to the equivalent ratio [NCO] / [NHx] of isocyanate groups [NCO] in the polyester prepolymer (A) having isocyanate groups and amino groups [NHx] in amines (B). Is usually 1/2 to 2/1, preferably 1.5 / 1 to 1 / 1.5, more preferably 1.2 / 1 to 1 / 1.2.
When [NCO] / [NHx] is more than 2 or less than 1/2, the molecular weight of the urea-modified polyester is lowered, and the hot offset resistance is deteriorated.

  The urea-modified polyester may contain a urethane bond together with a urea bond. The molar ratio of the urea bond content to the urethane bond content is usually 100/0 to 10/90, preferably 80/20 to 20/80, and more preferably 60/40 to 30/70. When the molar ratio of the urea bond is less than 10%, the hot offset resistance is deteriorated.

  The urea-modified polyester is produced by a one-shot method or the like. Polyhydric alcohol (PO) and polyvalent carboxylic acid (PC) are heated to 150-280 ° C. in the presence of a known esterification catalyst such as tetrabutoxytitanate, dibutyltin oxide, etc., and water generated while reducing the pressure as necessary. Distill off to obtain a polyester having a hydroxyl group. Subsequently, at 40-140 degreeC, this is made to react with polyvalent isocyanate (PIC), and the polyester prepolymer (A) which has an isocyanate group is obtained. Further, this (A) is reacted with amines (B) at 0 to 140 ° C. to obtain a urea-modified polyester.

  When reacting (PIC) and when reacting (A) and (B), a solvent may be used if necessary. Usable solvents include aromatic solvents (toluene, xylene, etc.); ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.); esters (ethyl acetate, etc.); amides (dimethylformamide, dimethylacetamide, etc.) and ethers And those inert to isocyanates (PIC), such as tetrahydrofuran (such as tetrahydrofuran).

  In addition, in the crosslinking and / or elongation reaction between the polyester prepolymer (A) and the amines (B), a reaction terminator may be used as necessary to adjust the molecular weight of the resulting urea-modified polyester. Examples of the reaction terminator include monoamines (diethylamine, dibutylamine, butylamine, laurylamine, etc.), and those blocked (ketimine compounds).

  The weight average molecular weight of the urea-modified polyester is usually 10,000 or more, preferably 20,000 to 10,000,000, and more preferably 30,000 to 1,000,000. If it is less than 10,000, the hot offset resistance deteriorates. The number average molecular weight of the urea-modified polyester or the like is not particularly limited when the above-mentioned unmodified polyester is used, and may be a number average molecular weight that can be easily obtained to obtain the weight average molecular weight. When the urea-modified polyester is used alone, its number average molecular weight is usually 2000-15000, preferably 2000-10000, more preferably 2000-8000. When it exceeds 20000, the low-temperature fixability and the glossiness when used in a full-color device are deteriorated.

  By using the unmodified polyester and the urea-modified polyester in combination, the low-temperature fixability and the gloss when used in the full-color image forming apparatus 100 are improved. Therefore, it is preferable to use the urea-modified polyester alone. The unmodified polyester may include a polyester modified with a chemical bond other than a urea bond.

  The unmodified polyester and the urea-modified polyester are preferably at least partially compatible with each other in terms of low-temperature fixability and hot offset resistance. Therefore, it is preferable that the unmodified polyester and the urea-modified polyester have a similar composition.

  The weight ratio of unmodified polyester to urea-modified polyester is usually 20/80 to 95/5, preferably 70/30 to 95/5, more preferably 75/25 to 95/5, and particularly preferably 80 /. 20-93 / 7. When the weight ratio of the urea-modified polyester is less than 5%, the hot offset resistance is deteriorated, and it is disadvantageous in terms of both heat-resistant storage stability and low-temperature fixability.

  The glass transition point (Tg) of the binder resin containing unmodified polyester and urea-modified polyester is usually 45 to 65 ° C, preferably 45 to 60 ° C. If it is less than 45 ° C., the heat resistance of the toner deteriorates, and if it exceeds 65 ° C., the low-temperature fixability becomes insufficient.

In addition, since the urea-modified polyester is likely to be present on the surface of the obtained toner base particles, the heat-resistant storage stability tends to be good even when the glass transition point is low as compared with known polyester-based toners.
(Coloring agent)

As the colorant, all known dyes and pigments can be used. 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 Dan, Lead Zhu, Cadmium Red, Cadmium Mercury Red, Antimon Zhu, Permanent Red 4R, Para Red, Phi Sayred, Parachlor Ortonito Aniline Red, Resol Fast Scarlet G, Brilliant Fast Scarlet, Brilliant Carmine B, Permanent Red (F2R, F4R, FRL, FRLL, F4RH), Fast Scarlet VD, Belkan Fast Rubin B, Brilliant Scarlet G, Resol 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 Lake, Rhodamine Lake B, Rhodamine Lake Y, Alizarin Lake, Thio Indigo Red B, Thioindigo Maroon, Oil Red, Quinacridone Red, Pyrazolone Red Polyazo Red, Chrome Vermillion, 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 blue, 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 Gold, Acid Green Lake, Malachite Green Lake, Lid Russian nin green, anthraquinone green, titanium oxide, zinc white, litbon and mixtures thereof can be used. The content of the colorant is usually 1 to 15% by weight, preferably 3 to 10% by weight, based on the toner.

The colorant can also be used as a master batch combined with a resin. As a binder resin to be kneaded together with the production of the master batch or the master batch, a polymer of styrene such as polystyrene, poly-p-chlorostyrene, polyvinyl toluene or the like, or a copolymer of these and a vinyl compound, Polymethyl methacrylate, polybutyl methacrylate, polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, polyester, epoxy resin, epoxy polyol resin, polyurethane, polyamide, 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 can be mentioned, and these can be used alone or in combination.
(Charge control agent)

Known charge control agents can be used, such as nigrosine dyes, triphenylmethane dyes, chromium-containing metal complex dyes, molybdate chelate pigments, rhodamine dyes, alkoxy amines, quaternary ammonium salts (fluorine-modified 4 Secondary ammonium salts or compounds, tungsten simple substances or compounds, fluorine activators, salicylic acid metal salts, and metal salts of salicylic acid derivatives. Specifically, Bontron 03 of a nigrosine dye, Bontron P-51 of a quaternary ammonium salt, Bontron S-34 of a metal-containing azo dye, E-82 of an oxynaphthoic acid metal complex, E-84 of a salicylic acid metal complex , Phenol-based 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 (from Hoechst), LRA-901, boron complex LR-147 (manufactured by Nippon Carlit), copper phthalocyanine, perylene, quinacridone, azo pigments, and other polymer compounds having functional groups such as sulfonic acid groups, carboxyl groups, and quaternary ammonium salts. Of these, substances that control the negative polarity of the toner are particularly preferably used.

The amount of the charge control agent used is determined by the type of binder resin, the presence or absence of additives used as necessary, and the toner production method including the dispersion method, and is not uniquely limited. Preferably, it is used in the range of 0.1 to 10 parts by weight with respect to 100 parts by weight of the binder resin. The range of 0.2 to 5 parts by weight is preferable. When the amount exceeds 10 parts by weight, the chargeability of the toner is too high, the effect of the charge control agent is reduced, the electrostatic attraction with the developing roller is increased, the developer fluidity is lowered, and the image density is lowered. Invite.
(Release agent)

As a release agent, a low melting point wax having a melting point of 50 to 120 ° C. works more effectively as a release agent in the dispersion with the binder resin between the fixing roller and the toner interface. The effect on high temperature offset is exhibited without applying a release agent such as oil. Examples of such a wax component include the following. 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, and paraffin, microcrystalline, And petroleum waxes such as petrolatum. In addition to these natural waxes, synthetic hydrocarbon waxes such as Fischer-Tropsch wax and polyethylene wax, and synthetic waxes such as esters, ketones, and ethers can be used. Furthermore, fatty acid amides such as 12-hydroxystearic acid amide, stearic acid amide, phthalic anhydride imide, chlorinated hydrocarbon, and low molecular weight crystalline polymer resin, poly-n-stearyl methacrylate, poly-n- A crystalline polymer having a long alkyl group in the side chain such as a homopolymer or copolymer of polyacrylate such as lauryl methacrylate (for example, a copolymer of n-stearyl acrylate-ethyl methacrylate, etc.) can also be used. .

The charge control agent and the release agent can be melt-kneaded together with the master batch and the binder resin, and of course, they may be added when dissolved and dispersed in the organic solvent.
(External additive)

  Inorganic fine particles are preferably used as an external additive for assisting the fluidity, developability and chargeability of the toner particles. The primary particle diameter of the inorganic fine particles is preferably 5 × 10 −3 to 2 μm, and particularly preferably 5 × 10 −3 to 0.5 μm. Moreover, it is preferable that the specific surface area by BET method is 20-500 m <2> / g. The use ratio of the inorganic fine particles is preferably 0.01 to 5 wt% of the toner, and particularly preferably 0.01 to 2.0 wt%.

Specific examples of the inorganic fine particles include, for example, silica, alumina, titanium oxide, barium titanate, magnesium titanate, calcium titanate, strontium titanate, zinc oxide, tin oxide, quartz sand, clay, mica, wollastonite, diatomaceous earth. Examples include soil, chromium oxide, cerium oxide, bengara, antimony trioxide, magnesium oxide, zirconium oxide, barium sulfate, barium carbonate, calcium carbonate, silicon carbide, and silicon nitride. Among these, as the fluidity imparting agent, it is preferable to use hydrophobic silica fine particles and hydrophobic titanium oxide fine particles in combination. In particular, when stirring and mixing are performed using particles having an average particle size of 5 × 10-2 μm or less, the electrostatic force and van der Waals force with the toner are remarkably improved. Even when stirring and mixing inside the developing device is performed, a fluidity-imparting agent is not detached from the toner, a good image quality that does not cause fireflies and the like is obtained, and a reduction in residual toner is further achieved. .

Titanium oxide fine particles are excellent in environmental stability and image density stability, but have a tendency to deteriorate the charge rise characteristics. Therefore, if the amount of titanium oxide fine particles added is larger than the amount of silica fine particles added, this side effect is affected. It can be considered large.
However, when the added amount of the hydrophobic silica fine particles and the hydrophobic titanium oxide fine particles is in the range of 0.3 to 1.5 wt%, the charge rising characteristics are not greatly impaired, and the desired charge rising characteristics can be obtained, that is, repeated copying. Stable image quality can be obtained even if

Next, a toner manufacturing method will be described. Here, although a preferable manufacturing method is shown, it is not limited to this.
(Toner production method)

1) A toner material solution is prepared by dispersing a colorant, unmodified polyester, a polyester prepolymer having an isocyanate group, and a release agent in an organic solvent.
The organic solvent is preferably volatile with a boiling point of less than 100 ° C. from the viewpoint of easy removal after toner base particle formation. Specifically, toluene, xylene, benzene, carbon tetrachloride, methylene chloride, 1,2-dichloroethane, 1,1,2-trichloroethane, trichloroethylene, chloroform, monochlorobenzene, dichloroethylidene, methyl acetate, ethyl acetate, methyl ethyl ketone, Methyl isobutyl ketone and the like can be used alone or in combination of two or more. In particular, aromatic solvents such as toluene and xylene and halogenated hydrocarbons such as methylene chloride, 1,2-dichloroethane, chloroform and carbon tetrachloride are preferred. The usage-amount of an organic solvent is 0-300 weight part normally with respect to 100 weight part of polyester prepolymers, Preferably it is 0-100 weight part, More preferably, it is 25-70 weight part.

2) The toner material liquid is emulsified in an aqueous medium in the presence of a surfactant and resin fine particles.
The aqueous medium may be water alone or an organic solvent such as alcohol (methanol, isopropyl alcohol, ethylene glycol, etc.), dimethylformamide, tetrahydrofuran, cellosolves (methyl cellosolve, etc.), lower ketones (acetone, methyl ethyl ketone, etc.). It may be included.

  The amount of the aqueous medium used relative to 100 parts by weight of the toner material liquid is usually 50 to 2000 parts by weight, preferably 100 to 1000 parts by weight. If the amount is less than 50 parts by weight, the dispersion state of the toner material liquid is poor, and toner particles having a predetermined particle diameter cannot be obtained. If it exceeds 2000 parts by weight, it is not economical.

Further, in order to improve the dispersion in the aqueous medium, a dispersant such as a surfactant and resin fine particles is appropriately added.
As surfactants, anionic surfactants such as alkylbenzene sulfonates, α-olefin sulfonates, phosphate esters, alkylamine salts, amino alcohol fatty acid derivatives, polyamine fatty acid derivatives, amine salt types such as imidazoline, Quaternary ammonium salt type cationic surfactants such as alkyltrimethylammonium salts, dialkyldimethylammonium salts, alkyldimethylbenzylammonium salts, pyridinium salts, alkylisoquinolinium salts, benzethonium chloride, fatty acid amide derivatives, polyhydric alcohols Nonionic surfactants such as derivatives, for example, amphoteric surfactants such as alanine, dodecyldi (aminoethyl) glycine, di (octylaminoethyl) glycine and N-alkyl-N, N-dimethylammonium betaine And the like.

Further, by using a surfactant having a fluoroalkyl group, the effect can be obtained in a very small amount. Preferred anionic surfactants having a fluoroalkyl group include fluoroalkyl carboxylic acids having 2 to 10 carbon atoms and metal salts thereof, disodium perfluorooctanesulfonyl glutamate, 3- [ω-fluoroalkyl (C6-C11 ) Oxy] -1-alkyl (C3-C4) sodium sulfonate, 3- [ω-fluoroalkanoyl (C6-C8) -N-ethylamino] -1-propanesulfonic acid sodium, fluoroalkyl (C11-C20) carvone Acids and metal salts, perfluoroalkylcarboxylic acids (C7 to C13) and metal salts thereof, perfluoroalkyl (C4 to C12) sulfonic acids and metal salts thereof, perfluorooctanesulfonic acid diethanolamide, N-propyl-N- ( 2-Hydroxyethyl) Perful Olooctanesulfonamide, perfluoroalkyl (C6-C10) sulfonamidopropyltrimethylammonium salt, perfluoroalkyl (C6-C10) -N-ethylsulfonylglycine salt, monoperfluoroalkyl (C6-C16) ethyl phosphate, etc. Can be mentioned.

  Product names include Surflon S-111, S-112, S-113 (Asahi Glass Co., Ltd.), Florard FC-93, FC-95, FC-98, FC-129 (Sumitomo 3M Co., Ltd.), Unidyne DS-101. DS-102 (manufactured by Daikin Industries, Ltd.), Megafac F-110, F-120, F-113, F-191, F-812, F-833 (manufactured by Dainippon Ink, Inc.), Xtop EF-102, 103, 104, 105, 112, 123A, 123B, 306A, 501, 201, 204 (manufactured by Tochem Products), and Fgentent F-100, F150 (manufactured by Neos).

  Moreover, as the cationic surfactant, aliphatic quaternary ammonium such as aliphatic primary, secondary or secondary amic acid, perfluoroalkyl (C6-C10) sulfonamidopropyltrimethylammonium salt which has a right fluoroalkyl group is used. Salts, benzalkonium salts, benzethonium chloride, pyridinium salts, imidazolinium salts, trade names include Surflon S-121 (Asahi Glass Co., Ltd.), Florard FC-135 (Sumitomo 3M Co., Ltd.), Unidyne DS-202 (Daikin Industries) Smoke), Megafac F-150, F-824 (Dainippon Ink Co., Ltd.), Xtop EF-132 (Tochem Products), Footage F-300 (Neos), and the like.

  The resin fine particles are added to stabilize the toner base particles formed in the aqueous medium. For this reason, it is preferable to add so that the coverage existing on the surface of the toner base particles is in the range of 10 to 90%. For example, polymethyl methacrylate fine particles 1 μm and 3 μm, polystyrene fine particles 0.5 μm and 2 μm, poly (styrene-acrylonitrile) fine particles 1 μm, trade names are PB-200H (manufactured by Kao Corporation), SGP (manufactured by Soken Co., Ltd.), Techno Examples include polymer SB (manufactured by Sekisui Chemical Co., Ltd.), SGP-3G (manufactured by Sokensha), and micropearl (manufactured by Sekisui Fine Chemical Co., Ltd.).

In addition, inorganic compound dispersants such as tricalcium phosphate, calcium carbonate, titanium oxide, colloidal silica, and hydroxyapatite can also be used.
As a dispersant that can be used in combination with the above resin fine particles and inorganic compound dispersant, the dispersed droplets may be stabilized by a polymer protective colloid. For example, acrylic acid, methacrylic acid, α-cyanoacrylic acid, α-cyanomethacrylic acid, itaconic acid, crotonic acid, fumaric acid, maleic acid or maleic anhydride and other (meth) acrylic monomers containing hydroxyl groups Bodies such as acrylic acid-β-hydroxyethyl, methacrylic acid-β-hydroxyethyl, acrylic acid-β-hydroxypropyl, methacrylic acid-β-hydroxypropyl, acrylic acid-γ-hydroxypropyl, methacrylic acid-γ-hydroxy Propyl, acrylic acid-3-chloro-2-hydroxypropyl, methacrylic acid-3-chloro-2-hydroxypropyl, diethylene glycol monoacrylate, diethylene glycol monomethacrylate, glycerol monoacrylate, glycerol monomethacrylate Luric acid esters, N-methylol acrylamide, N-methylol methacrylamide, etc., vinyl alcohol or ethers with vinyl alcohol, such as vinyl methyl ether, vinyl ethyl ether, vinyl propyl ether, or compounds containing vinyl alcohol and a carboxyl group Esters such as vinyl acetate, vinyl propionate, vinyl butyrate, acrylamide, methacrylamide, diacetone acrylamide or their methylol compounds, acid chlorides such as acrylic acid chloride, methacrylic acid chloride, vinyl pyridine, vinyl pyrrolidone, vinyl Homopolymers or copolymers such as nitrogen-containing compounds such as imidazole and ethyleneimine, or those having a heterocyclic ring thereof,
Polyoxyethylene, polyoxypropylene, polyoxyethylene alkylamine, polyoxypropylene alkylamine, polyoxyethylene alkylamide, polyoxypropylene alkylamide, polyoxyethylene nonylphenyl ether, polyoxyethylene lauryl phenyl ether, polyoxyethylene stearyl Polyoxyethylenes such as phenyl ester and polyoxyethylene nonylphenyl ester, and celluloses such as methyl cellulose, hydroxyethyl cellulose, and hydroxypropyl cellulose can be used.

  The dispersion method is not particularly limited, and known equipment such as a low-speed shear method, a high-speed shear method, a friction method, a high-pressure jet method, and an ultrasonic wave can be applied. Among these, the high-speed shearing method is preferable in order to make the particle size of the dispersion 2 to 20 μm. When a high-speed shearing disperser is used, the rotational speed is not particularly limited, but is usually 1000 to 30000 rpm, preferably 5000 to 20000 rpm. The dispersion time is not particularly limited, but in the case of a batch method, it is usually 0.1 to 5 minutes. The temperature during dispersion is usually 0 to 150 ° C. (under pressure), preferably 40 to 98 ° C.

3) At the same time as the preparation of the emulsion, the amines (B) are added to cause a reaction with the polyester prepolymer (A) having an isocyanate group.
This reaction involves molecular chain crosslinking and / or elongation. The reaction time is selected depending on the reactivity between the isocyanate group structure of the polyester prepolymer (A) and the amines (B), but is usually 10 minutes to 40 hours, preferably 2 to 24 hours. The reaction temperature is generally 0 to 150 ° C, preferably 40 to 98 ° C. Moreover, a well-known catalyst can be used as needed. Specific examples include dibutyltin laurate and dioctyltin laurate.

4) After completion of the reaction, the organic solvent is removed from the emulsified dispersion (reactant), washed and dried to obtain toner base particles.
In order to remove the organic solvent, the temperature of the entire system is gradually raised in a laminar stirring state, and after giving strong stirring in a certain temperature range, the solvent base is removed to produce spindle-shaped toner base particles. . Further, when an acid such as calcium phosphate salt or an alkali-soluble material is used as the dispersion stabilizer, the calcium phosphate salt is dissolved from the toner base particles by a method such as dissolving the calcium phosphate salt with an acid such as hydrochloric acid and washing with water. Remove. It can also be removed by operations such as enzymatic degradation.
5) A charge control agent is injected into the toner base particles obtained above, and then inorganic fine particles such as silica fine particles and titanium oxide fine particles are externally added to obtain a toner.

The injection of the charge control agent and the external addition of the inorganic fine particles are performed by a known method using a mixer or the like.
Thereby, a toner having a small particle size and a sharp particle size distribution can be easily obtained. Furthermore, by giving strong agitation in the process of removing the organic solvent, the shape between the true spherical shape and the rugby ball shape can be controlled, and the surface morphology is also controlled between the smooth shape and the umeboshi shape. be able to.

1 is a schematic diagram illustrating a configuration of an image forming apparatus according to an embodiment of the present invention. FIG. 2 is a schematic diagram illustrating a configuration of a process cartridge of the image forming apparatus illustrated in FIG. 1. It is a figure which shows the structure of the fur brush which concerns on this invention. It is explanatory drawing which shows the fur brush which concerns on this invention. (A), (b) is the figure which represented typically the shape of the toner for demonstrating shape factor SF-1 and shape factor SF-2. (A), (b) is a graph which shows the flow curve of the tester which measures the outflow start temperature of a toner.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 2A, 2B, 2C, 2D Image forming part 21 Process cartridge 3 Transfer apparatus 31 Transfer belt 5 Photoreceptor (image carrier)
6 Exposure device 7 Double-side unit 8 Reversing unit 9 Fixing device 10 Developing device 11, 12 Paper feed cassette 13 Manual feed tray 14 Charging device 141 Charging roller 142 Charging roller cleaning brush 15 Cleaning device 100 Base cloth 110 Core metal 120 Brush bunch 1 bundle 152 Blade pressure spring 153 Blade rotation fulcrum 154 Cleaning blade support 155 Waste toner collection coil 158 Flicker 161 Fur brush 162 Lubricant coating agent (lubricant molding)
163 Lubricant molded body pressure spring

Claims (13)

A fur brush that removes residual toner and other residual toner on the image carrier and scrapes the solid lubricity-imparting material and applies a lubricant on the image carrier. In the cleaning device having a length over an image writing area where the image of the image carrier is written and a non-image area where the image is not written,
The fur brush has a bristle foot length located in the image writing region in a longitudinal direction shorter than a brush bristle length located in the non-image region, and the solid lubricity is imparted by the brush hair in the image writing region. A cleaning device , wherein a cutting force of a material is higher than that of the non-image area . The cleaning device according to claim 1 ,
The fur brush has a brush bristles length difference between an image area and a non-image area of 0.05 mm to 0.5 mm. The cleaning device according to claim 1 or 2 ,
A cleaning device using polyester fiber as a material of the fur brush hair. The cleaning device according to any one of claims 1 to 3 ,
A cleaning apparatus, wherein a polyester fiber which is a material of the fur brush hair and a base fabric on which the fiber is sewn is an insulating material. The cleaning device according to any one of claims 1 to 4 ,
In the fur brush, a cleaning device is characterized in that an adhesive for preventing the sewn polyester fibers from being unwound is an insulating material. In the cleaning device according to claim 1,
A cleaning apparatus comprising a solid state lubricity imparting agent pressed against the fur brush by a spring or its own weight. In an image forming apparatus that forms an image of powder toner on an image carrier,
An image forming apparatus wherein a toner remaining after transferring the image to a transfer member, is removed by a cleaning device according to any one of claims 1 to 6. The image forming apparatus according to claim 7 .
The toner has a weight average particle diameter of 3 to 8 μm and a ratio (D4 / D1) of the weight average particle diameter (D4) to the number average particle diameter (D1) is in the range of 1.00 to 1.40. An image forming apparatus. The image forming apparatus according to claim 7 .
The image forming apparatus, wherein the toner has a shape factor SF-1 in the range of 100 to 180 and a shape factor SF-2 in the range of 100 to 180. The image forming apparatus according to claim 7 .
The image forming apparatus, wherein the toner is a toner obtained by externally adding fine particles having an average primary particle diameter of 50 to 500 nm and a bulk density of 0.3 g / cm 3 or more on the surface of toner base particles. The image forming apparatus according to claim 7 .
The image forming apparatus, wherein the toner comprises at least a binder resin, a colorant, and a release agent, and has a glass transition temperature of 45 to 65 ° C. and an outflow start temperature of 90 to 115 ° C. The image forming apparatus according to claim 7 .
In the toner, a toner material liquid in which at least a polyester prepolymer having a functional group containing a nitrogen atom, polyester, a colorant, and a release agent is dispersed in an organic solvent is crosslinked and / or extended in an aqueous medium. An image forming apparatus, characterized in that the toner is obtained by processing. An image carrier for carrying a latent image;
In a process cartridge that is integrally supported and includes at least a cleaning unit that cleans the surface of the image carrier after transfer, and is detachably formed on the main body of the image forming apparatus.
The process cartridge according to claim 1, wherein the cleaning unit is the cleaning device according to claim 1.

Images