JP2005099126A - Cleaning device, process cartridge, image forming apparatus, and toner used for the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cleaning device which can supply a specified amount of a lubricant to an image carrier and/or an intermediate transmission member by allowing the lubricant to abut on a supplying member always under a constant pressure, and to provide a process cartridge, an image forming apparatus, and toner used for the same. <P>SOLUTION: The cleaning device has a brush roll 182 which supplies the lubricant to a photoreceptor 40 or an intermediate transfer belt 10, the lubricant 181, and a spring 183 which allows the lubricant 181 to abut on the brush roll 182 and has a cam 184 as a pressure maintaining mechanism to maintain the pressurizing force of the spring 183 constant. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a cleaning device, a process cartridge, an image forming apparatus, and a toner used in the image forming by an electrostatic copying process such as a copying machine, a facsimile machine, and a printer.

Representative methods of color image formation include a direct transfer system in which toner images of different colors formed on a plurality of photoconductors are transferred while being directly superimposed on a recording medium, and toners of different colors formed on a plurality of photoconductors. There is an intermediate transfer method in which an image is transferred while being superimposed on an intermediate transfer member, and then transferred onto a recording medium in a lump. Since a plurality of photoconductors are arranged side by side facing a recording medium or an intermediate transfer body, this is called a tandem method, and yellow (Y), magenta (M), cyan (C), and black (K) for each photoconductor. An electrophotographic process such as formation and development of an electrostatic latent image is executed for each color, and the image is transferred onto a running recording medium in the direct transfer method, or onto a running intermediate transfer member in the intermediate transfer method.
In the tandem color image forming apparatus using each of these methods, the direct transfer method receives an endless belt that runs while supporting a recording medium, and the intermediate transfer method receives an image from a photoreceptor. Generally, an endless belt to be carried is employed. Then, an image forming unit including four photoconductors is installed side by side on one running side of the belt.

In the above tandem color image forming apparatus, when the image on the intermediate transfer belt or the photosensitive member is transferred to the next image carrier (including the recording medium), the remaining image remains without being completely transferred. In general, a cleaning unit such as a blade or a brush is installed for cleaning. The photosensitive member, the intermediate transfer belt, and the direct transfer belt need to have an image drawn directly on the photosensitive member, the intermediate transfer belt, and the direct transfer belt, and the density of the image must be monitored with an optical sensor or the like.
As described above, the cleaning method generally involves scraping an image from an image carrier such as an intermediate transfer belt, a direct transfer belt, or a photoreceptor with a blade, a brush, etc., but these methods do not provide sufficient cleaning properties. In this case, there is a method in which a lubricant such as zinc steering acid is applied to the surface of the image carrier with a brush roller. In addition, high cleaning properties are required for the polymerized toner, and the lubricant coating method is attracting attention.

Patent Document 1 discloses a tandem type image forming apparatus provided with irregular particle supply means for supplying irregular particles to an intermediate transfer member and to supply a cleaning blade that contacts the respective photosensitive members via the intermediate transfer member. Has been. As a result, the irregularly shaped particles of the cleaning blade edge enter the irregularly shaped particles to prevent the spherical toner from passing through the cleaning blade during image formation, thereby improving the cleaning property.
However, when the lubricant is continuously applied, the lubricant is scraped, and the Malus contact pressure by the spring becomes smaller than that at the time of installation, the amount of Malus applied is reduced, and a sufficient μ reduction of the image carrier cannot be obtained. There is. As a result, the cleaning properties differ greatly between the initial use and the passage of time.

JP 2001-166659 A

  Therefore, the present invention has been made in view of the above problems, and the problem is that a constant amount of the lubricant is brought into contact with the supply member at a constant pressure so that a certain amount of the lubricant is applied to the image carrier and / or the intermediate transfer member. Another object of the present invention is to provide a cleaning device, a process cartridge, an image forming apparatus, and a toner used for these, which can supply a lubricant.

The features of the present invention, which is a means for solving the above problems, are listed below.
The cleaning device of the present invention is a cleaning device in which a cleaning blade for cleaning toner on an image carrier or an intermediate transfer member and a brush roller for applying a lubricant of a lubricant molding to the image carrier or intermediate transfer member are arranged. The cleaning device includes a lubricant supply member that supplies a lubricant to the image carrier or the intermediate transfer member, a lubricant, and a lubricant pressure member that causes the lubricant to contact the lubricant supply member, and the lubricant pressure member. A cleaning device having a pressure holding mechanism that keeps the applied pressure constant.
Alternatively, the cleaning device of the present invention is further characterized in that the pressure holding mechanism keeps the applied pressure constant by a cam.
Alternatively, the cleaning device of the present invention is further characterized in that the pressure holding mechanism keeps the applied pressure constant by an air spring.
Alternatively, in the cleaning device of the present invention, the pressure holding mechanism is manually adjusted to keep the applied pressure constant.
Alternatively, the cleaning device of the present invention is characterized in that the pressure holding mechanism keeps the pressure constant constant step by step according to the number of sheets passing through.
Alternatively, in the cleaning device according to the present invention, the pressure holding mechanism further detects the length of the sliding member pressurizing member and keeps the applied pressure constant.
Alternatively, in the cleaning device of the present invention, the pressure holding mechanism further includes a pressure sensor disposed in the vicinity of the lubricant, thereby detecting the pressure between the lubricant and the image carrier that is in contact with the lubricant, Cleaning device characterized by keeping constant.
Alternatively, in the cleaning device of the present invention, the lubricant further abuts against the lubricant supply agent by its own weight.

A process cartridge according to the present invention includes at least an image carrier that carries a latent image and a cleaning device that cleans toner on the image carrier, and the process cartridge that can be attached to and detached from the main body of the image forming apparatus. A pressure holding mechanism that has a lubricant supply member that supplies a lubricant to the carrier, a lubricant, and a lubricant pressure member that abuts the lubricant against the lubricant supply member, and that keeps the pressure applied to the lubricant pressure member constant. It is characterized by having.
Alternatively, in the process cartridge according to the present invention, the cleaning device is the cleaning device according to any one of claims 2 to 8.

The image forming apparatus of the present invention forms an image bearing member that carries a latent image, a charging device that charges the image bearing member by bringing a charging member into contact with or close to the surface of the image bearing member, and a latent image on the image bearing member. A transfer electric field is generated between the latent image forming device, the developing device for developing toner by attaching the toner to the latent image on the image carrier, and the intermediate transfer member and / or the recording member that moves while contacting the image carrier. An image forming apparatus comprising: a transfer device that forms and transfers a toner image formed on an image carrier onto an intermediate transfer member and / or a recording member; and a cleaning device that cleans toner on the image carrier. The cleaning apparatus includes a lubricant supply member that supplies a lubricant to the image carrier and / or the intermediate transfer member, a lubricant, and a lubricant pressure member that abuts the lubricant against the lubricant supply member. Pressure holding machine that keeps the pressure applied to the pressure member constant An image forming apparatus having a structure.
The image forming apparatus of the present invention is further characterized in that the cleaning device is the cleaning device according to any one of claims 2 to 8.

The image forming apparatus according to the present invention further includes the process cartridge according to claim 10 or 11.
In the image forming apparatus of the present invention, the toner further has a volume average particle diameter (Dv) in the range of 3 to 8 μm, and a ratio between the volume average particle diameter (Dv) and the number average particle diameter (Dn). An image forming apparatus having a dispersion degree defined by (Dv / Dn) in a range of 1.00 to 1.40.
The image forming apparatus of the present invention is further characterized in that the toner has an average circularity in the range of 0.93 to 1.00.
Further, the image forming apparatus of the present invention is characterized in that the toner is in the range of 100 to 180 in terms of the shape factor SF-1 and in the range of 100 to 180 in terms of the shape factor SF-2. Forming equipment.
Further, in the image forming apparatus of the present invention, the toner has a substantially spherical appearance, and a ratio of the major axis to the minor axis (r2 / r1) is in the range of 0.5 to 1.0. The ratio of thickness to minor axis (r3 / r2) is in the range of 0.7 to 1.0, and satisfies the relationship of major axis r1 ≧ minor axis r2 ≧ thickness r3. apparatus.
In the image forming apparatus of the present invention, the toner further includes a toner composition containing at least a polyester prepolymer having a functional group containing a nitrogen atom, a polyester, a colorant, and a release agent in an aqueous medium. An image forming apparatus characterized in that a crosslinking and / or elongation reaction is carried out in the presence of.

The toner of the present invention includes an image carrier that carries a latent image, a charging device that charges the image carrier by bringing a charging member into contact with or close to the surface of the image carrier, and a latent image that forms a latent image on the image carrier. An image carrier is formed by forming a transfer electric field between the forming device, the developing device for developing toner by attaching the toner to the latent image on the image carrier, and the surface moving member that moves while contacting the image carrier. A transfer device for transferring a toner image formed on the body onto a recording member or a surface moving member sandwiched between the surface moving member, a cleaning blade, a brush roller, and a lubricant molding, The brush-like roller is insulative, and is applied to a toner used in an image forming apparatus provided with a cleaning device that applies a lubricant of a lubricant molding to an image carrier and transports the toner cleaned by a cleaning blade to the inside of the cleaning device. Oh The toner has a volume average particle diameter (Dv) in the range of 3 to 8 μm and a dispersion defined by a ratio (Dv / Dn) of the volume average particle diameter (Dv) to the number average particle diameter (Dn). A toner having a degree of 1.00 to 1.40.
The toner of the present invention further has an average circularity in the range of 0.93 to 1.00.
The toner of the present invention is further characterized by having 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.
Further, the toner of the present invention has a substantially spherical appearance, and the ratio of the major axis to the minor axis (r2 / r1) is in the range of 0.5 to 1.0. The toner is characterized in that the ratio (r3 / r2) is in the range of 0.7 to 1.0 and the relationship of major axis r1 ≧ minor axis r2 ≧ thickness r3 is satisfied.
Further, the toner of the present invention further comprises a cross-linking of a toner composition containing at least a polyester prepolymer having a functional group containing a nitrogen atom, a polyester, a colorant, and a release agent in the presence of resin fine particles in an aqueous medium. A toner characterized by undergoing an elongation reaction.

  According to the present invention, the friction coefficient of the photosensitive member and the intermediate transfer belt is reduced by making the amount of the lubricant removed by the brush roll by the pressure holding mechanism provided in the cleaning device constant regardless of the time. It is possible to clean even with a small particle size / spherical toner. Thereby, a high-definition image can be obtained stably.

The best mode for carrying out the present invention will be described below with reference to the drawings. Note that it is easy for a person skilled in the art to make other embodiments by changing or correcting the present invention within the scope of the claims, and these changes and modifications are included in the scope of the claims. The following description is an example of the best mode of the present invention, and does not limit the scope of the claims.
FIG. 1 is a schematic diagram showing a configuration of a tandem electrophotographic apparatus according to an embodiment of the present invention. In the tandem type electrophotographic apparatus, as shown in FIG. 1, images on each photosensitive member 1 as image carriers are sequentially transferred to an intermediate transfer member 4 by a primary transfer device 2 and then the intermediate transfer member. 4 is an indirect transfer type in which the image on 4 is collectively transferred to a sheet by the secondary transfer device 5.
In the present invention, the tandem type is described. However, the invention is not limited to the tandem type and is effective for an image forming apparatus using an intermediate transfer belt.
As shown in FIG. 2, the tandem type electrophotographic apparatus includes a direct transfer system in which an image on each photoconductor 1 is sequentially transferred onto a sheet conveyed by a sheet conveying belt 3 by a transfer apparatus 2, and FIG. As shown in FIG. 1, the images on the respective photoreceptors 1 are once sequentially transferred to the intermediate transfer member 4 by the primary transfer device 2 and then the images on the intermediate transfer member 4 are collectively transferred to the sheet by the secondary transfer device 5. Indirect transfer system.

  Comparing the direct transfer type and the indirect transfer type, the former has a sheet feeding device 6 arranged upstream of the tandem type image forming apparatus T in which the photoreceptors 1 are arranged, and a fixing device 7 arranged downstream. There is a disadvantage of increasing the size. On the other hand, since the latter can set the secondary transfer position relatively freely, the paper feeding device 6 and the fixing device 7 can be arranged so as to overlap the tandem type image forming apparatus T, and the size can be reduced. There are advantages that are possible. In the former case, the fixing device 7 is arranged close to the tandem type image forming apparatus T so as not to increase the size, so that the fixing device 7 can be arranged with a sufficient margin that the sheet can be bent. However, there is a defect that the fixing device 7 affects the image formation on the rear end side due to an impact when the leading edge of the sheet enters the fixing device 7 or a difference in sheet conveyance speed when passing through the fixing device 7. On the other hand, in the latter case, the fixing device 7 can be disposed with a sufficient margin that the sheet can be bent, so that the fixing device 7 hardly affects the image formation.

For these reasons, attention has recently been paid to the indirect transfer type among tandem type electrophotographic apparatuses.
In this type of color electrophotographic apparatus, as shown in FIG. 2, the transfer residual toner remaining on the photoconductor 1 after the primary transfer is removed by the photoconductor cleaning device 8 to clean the surface of the photoconductor 1. In preparation for another image formation. In addition, the transfer residual toner remaining on the intermediate transfer body 4 after the secondary transfer is removed by the intermediate transfer body cleaning device 9 to clean the surface of the intermediate transfer body 4 to prepare for another image transfer.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows an embodiment of the present invention, and shows the configuration of a tandem type indirect transfer system. In FIG. 1, reference numeral 100 denotes a copying machine body, 200 denotes a paper feed table on which the copying machine is placed, and 300 denotes a copying machine. A scanner 400 mounted on the main body 100, and an automatic document feeder (ADF) 400 further mounted thereon.
The copying machine main body 100 is provided with an endless belt-shaped intermediate transfer member 10 in the center. In the intermediate transfer member 10, the base layer is made of a material that hardly stretches, such as a fluororesin or a canvas, and an elastic layer is provided thereon. The elastic layer is made of, for example, fluororubber or acrylonitrile-butadiene copolymer rubber. The surface of the elastic layer is, for example, coated with a fluorine-based resin and covered with a smooth coat layer.
As shown in FIG. 1, in the illustrated example, it is wound around three support rollers 14, 15, and 16 so that it can be rotated and conveyed clockwise in the figure. In this illustrated example, an intermediate transfer body cleaning device 17 that removes residual toner remaining on the intermediate transfer body 10 after image transfer is provided to the left of the second support roller 15 among the three.
Further, four images of black, cyan, magenta, and yellow are formed on the intermediate transfer member 10 stretched between the first support roller 14 and the second support roller 15 among the three along the conveyance direction. The tandem image forming apparatus 20 is configured by arranging the forming units 18 side by side.
An exposure device 21 is further provided on the tandem image forming apparatus 20 as shown in FIG.

On the other hand, a secondary transfer device 22 is provided on the side opposite to the tandem image forming apparatus 20 with the intermediate transfer body 10 interposed therebetween. In the illustrated example, the secondary transfer device 22 is configured by spanning a secondary transfer belt 24, which is an endless belt, between two rollers 23, and is pressed against the third support roller 16 via the intermediate transfer body 10. The image on the intermediate transfer body 10 is transferred to a sheet.
A fixing device 25 for fixing the transfer image on the sheet is provided beside the secondary transfer device 22. The fixing device 25 is configured by pressing a pressure roller 27 against a fixing belt 26 that is an endless belt.
The secondary transfer device 22 described above is also provided with a sheet transport function for transporting the image-transferred sheet to the fixing device 25. Of course, a non-contact charger may be arranged as the secondary transfer device 22, and in such a case, it is difficult to provide this sheet conveyance function together.
In the illustrated example, under such a secondary transfer device 22 and a fixing device 25, a sheet reversing device 28 for reversing the sheet so as to record images on both sides of the sheet in parallel with the tandem image forming device 20 described above. Is provided.

Now, when making a copy using this color copying machine, a document is set on the document table 30 of the automatic document feeder 400. Alternatively, the automatic document feeder 400 is opened, a document is set on the contact glass 32 of the scanner 300, and the automatic document feeder 400 is closed and pressed by it.
When a start switch (not shown) is pressed, when the document is set on the automatic document feeder 400, the document is transported and moved onto the contact glass 32, and then the document is set on the other contact glass 32. At that time, the scanner 300 is immediately driven to travel the first traveling body 33 and the second traveling body 34. Then, the first traveling body 33 emits light from the light source and further reflects the reflected light from the document surface toward the second traveling body 34, and is reflected by the mirror of the second traveling body 34 and passes through the imaging lens 35. The document is placed in the reading sensor 36 and the original content is read.
When a start switch (not shown) is pressed, one of the support rollers 14, 15, and 16 is driven to rotate by a drive motor (not shown), and the other two support rollers are driven to rotate to convey the intermediate transfer member 10. To do. At the same time, the individual image forming means 18 rotates the photosensitive member 40 to form black, yellow, magenta, and cyan single-color images on each photosensitive member 40, respectively. Then, along with the conveyance of the intermediate transfer member 10, the single color images are sequentially transferred to form a composite color image on the intermediate transfer member 10.

On the other hand, when a start switch (not shown) is pressed, one of the paper feed rollers 42 of the paper feed table 200 is selectively rotated, and the sheet is fed out from one of the paper feed cassettes 44 provided in multiple stages in the paper bank 43, and the separation roller 45. Then, the sheets are separated one by one into the paper feed path 46, transported by the transport roller 47, guided to the paper feed path 48 in the copying machine main body 100, and abutted against the registration roller 49 and stopped.
Alternatively, the sheet feed roller 50 is rotated to feed out the sheets on the manual feed tray 51, separated one by one by the separation roller 52, put into the manual feed path 53, and abutted against the registration roller 49 and stopped.
Then, the registration roller 49 is rotated in synchronization with the composite color image on the intermediate transfer member 10, the sheet is fed between the intermediate transfer member 10 and the secondary transfer device 22, and transferred by the secondary transfer device 22. A color image is recorded on the sheet.
The image-transferred sheet is conveyed by the secondary transfer device 22 and sent to the fixing device 25. The fixing device 25 applies heat and pressure to fix the transferred image, and then the switching roller 55 is used to switch the discharge roller. The paper is discharged at 56 and stacked on the paper discharge tray 57. Alternatively, it is switched by the switching claw 55 and put into the sheet reversing device 28, where it is reversed and guided again to the transfer position, and an image is recorded also on the back surface, and then discharged onto the discharge tray 57 by the discharge roller 56.
On the other hand, the intermediate transfer body 10 after the image transfer is removed by the intermediate transfer body cleaning device 17 to remove residual toner remaining on the intermediate transfer body 10 after the image transfer, so that the tandem image forming apparatus 20 can prepare for another image formation.

Here, a conductive rubber roller is used as the registration roller 49, and a bias is applied. The surface is a conductive NBR rubber having a diameter of 18 mm and a thickness of 1 mm. The electrical resistance is about 10E9 Ωcm in terms of the volume resistance of the rubber material, and the applied voltage is about −850 V applied to the toner transfer side (front side).
Although a voltage of about +200 V is applied to the back side of the paper, it may be grounded especially when there is little need to consider paper dust transfer on the back side. Further, a DC bias is applied as the applied voltage, but this may be an AC voltage having a DC offset component.
The AC superimposed DC bias can uniformly charge the paper surface. The paper surface after passing through the registration roller 49 is slightly negatively charged. Therefore, in the transfer from the intermediate transfer body 10 to the sheet, care should be taken because the transfer conditions may change compared to the case where no voltage is applied to the registration roller 49.

FIG. 4 is a schematic diagram illustrating a configuration of a main part of the tandem image forming apparatus.
Now, in the tandem image forming apparatus 20 described above, the individual image forming means 18 includes, for example, a charging device 60, a developing device 61, and a primary device around a drum-shaped photoconductor 40 as shown in FIG. The image forming apparatus includes a transfer device 62, a photoconductor cleaning device 63, a charge removal device 64, and the like. In the illustrated example, the photosensitive member 40 has a drum shape in which a photosensitive organic photosensitive material is applied to a base tube made of aluminum or the like to form a photosensitive layer. However, the photosensitive member 40 may have an endless belt shape.
Although not shown in the drawing, at least the photoconductor 40 is provided, and a process cartridge is formed by all or a part of the part constituting the image forming unit 18, and is removable from the copying machine main body 100 in a lump to improve maintenance. You may do it.
Of the portions constituting the image forming unit 18, the charging device 60 is formed in a roller shape in the illustrated example, and charges the photosensitive member 40 by applying a voltage in contact with the photosensitive member 40.
The developing device 61 may use a one-component developer. However, in the illustrated example, a two-component developer composed of a magnetic carrier and a nonmagnetic toner is used. Then, the agitation unit 66 that conveys the two-component developer while stirring and adheres to the developing sleeve 65, and the developing unit 67 that transfers the toner of the two-component developer attached to the developing sleeve 65 to the photoreceptor 40. The stirring unit 66 is positioned lower than the developing unit 67.
The stirring unit 66 is provided with two parallel screws 68. The two screws 68 are partitioned by a partition plate 69 except for both ends. A toner concentration sensor 71 is attached to the developing case 70.

On the other hand, the developing portion 67 is provided with a developing sleeve 65 facing the photoreceptor 40 through the opening of the developing case 70, and a magnet 72 is fixedly provided in the developing sleeve 65. Further, a doctor blade 73 is provided with the tip approaching the developing sleeve 65. In the illustrated example, the distance at the closest portion between the doctor blade 73 and the developing sleeve 65 is set to 500 μm.
Then, the two-component developer is conveyed and circulated while being stirred by the two screws 68 and supplied to the developing sleeve 65. The developer supplied to the developing sleeve 65 is drawn up and held by the magnet 72 to form a magnetic brush on the developing sleeve 65. The magnetic brush is trimmed to an appropriate amount by the doctor blade 73 as the developing sleeve 65 rotates. The developer that has been cut off is returned to the stirring unit 66.
On the other hand, of the developer on the developing sleeve 65, the toner is transferred to the photoreceptor 40 by the developing bias voltage applied to the developing sleeve 65, and the electrostatic latent image on the photoreceptor 40 is visualized. After the visualization, the developer remaining on the developing sleeve 65 leaves the developing sleeve 65 and returns to the stirring unit 66 where there is no magnetic force of the magnet 72. When the toner concentration in the stirring unit 66 becomes light by this repetition, it is detected by the toner concentration sensor 71 and the stirring unit 66 is replenished with toner.

Incidentally, in the illustrated example, the linear velocity of the photosensitive member 40 is 200 mm / s, and the linear velocity of the developing sleeve 65 is 240 mm / s. The developing process is performed with the diameter of the photoconductor 40 being 50 mm and the diameter of the developing sleeve 65 being 18 mm. The toner charge amount on the developing sleeve 65 is in the range of −10 to −30 μC / g. The development gap _GP, which is the gap between the photoconductor 40 and the development sleeve 65, can be set in the range of 0.8 mm to 0.4 mm, and the development efficiency can be improved by reducing the value.
The thickness of the photoreceptor 40 is 30 μm, the beam spot diameter of the optical system is 50 × 60 μm, and the light quantity is 0.47 mW. Further, the developing process is performed with the charging (pre-exposure) potential V ₀ of the photoreceptor 40 being −700 V, the post-exposure potential _VL being −120 V, and the developing bias voltage being −470 V, that is, the developing potential 350 V.
Next, the primary transfer device 62 is formed in a roller shape and is pressed against the photoconductor 40 with the intermediate transfer body 10 interposed therebetween. Separately, it is not limited to a roller shape, and may be a non-contact corona charger or the like.

The photoconductor cleaning device 63 is provided with a cleaning blade 75 made of polyurethane rubber, for example, with its tip pressed against the photoconductor 40, and the outer periphery of the photoconductor cleaning device 63 contacts the photoconductor 40 and rotates the conductive fur brush 76 in the direction of the arrow. Prepare freely. Further, a metal electric field roller 77 for applying a bias to the fur brush 76 is rotatably provided in the direction of the arrow, and the tip of the scraper 78 is pressed against the electric field roller 77. Further, a collection screw 79 for collecting the removed toner is provided.
Then, residual toner on the photoconductor 40 is removed by a fur brush 76 that rotates in the counter direction with respect to the photoconductor 40. The toner adhering to the fur brush 76 is removed by applying a bias by the electric field roller 77 that contacts the fur brush 76 and rotates in the counter direction. The electric field roller 77 is cleaned by a scraper 78. The toner collected by the photoconductor cleaning device 63 is brought to one side of the photoconductor cleaning device 63 by a collection screw 79, and returned to the developing device 61 by a toner recycling device 80, which will be described in detail, for reuse.
The static eliminator 64 is a lamp, for example, and initializes the surface potential of the photoreceptor 40 by irradiating light.

Then, along with the rotation of the photosensitive member 40, the surface of the photosensitive member 40 is first uniformly charged by the charging device 60, and then the writing light L from the exposure device 21 described above is emitted from the exposure device 21 according to the reading content of the scanner 300. Irradiation forms an electrostatic latent image on the photoreceptor 40.
Thereafter, toner is attached by the developing device 61 to visualize the electrostatic latent image, and the visible image is transferred onto the intermediate transfer member 10 by the primary transfer device 62. The surface of the photoconductor 40 after the image transfer is cleaned by removing residual toner with the photoconductor cleaning device 63, and is neutralized with the static eliminator 64 to prepare for another image formation.

In FIG. 4, each image forming unit 18 of the tandem image forming apparatus 20, each photoconductor 40 of the image forming unit 18, each developing device 61, each photoconductor cleaning device 63, and the photoconductor 40 of each image forming unit 18. After the respective symbols of the primary transfer devices 62 provided opposite to each other, BK is indicated for black, Y is indicated for yellow, M is indicated for magenta, and C is indicated for cyan. .
4 is a conductive roller provided in contact with the base layer 11 side of the intermediate transfer body 10 between the primary transfer devices 62, although not shown in FIGS. This conductive roller 74 prevents the bias applied by each primary transfer device 62 during transfer from flowing into the adjacent image forming means 18 via the intermediate resistance base layer 11.

Next, FIGS. 5 and 6 are schematic views showing the configuration of the toner recycling apparatus. As shown in FIG. 5, the recovery screw 79 of the photoconductor cleaning device 63 is provided with a roller portion 82 having a pin 81 at one end. Then, one side of the belt-like collected toner conveying member 83 of the toner recycling device 80 is hung on the roller portion 82, and a pin 81 is inserted into the long hole 84 of the collected toner conveying member 83. The outer periphery of the collected toner conveying member 83 is provided with blades 85 at regular intervals, and the other side is hung on the roller portion 87 of the rotating shaft 86.
The collected toner conveyance member 83 is placed in the conveyance path case 88 shown in FIG. The conveyance path case 88 is formed integrally with the cartridge case 89, and one of the above-described two screws 68 of the developing device 61 is placed at the end of the developing device 61 side.
Then, the driving force is transmitted from the outside to rotate the collection screw 79, and the collection toner conveying member 83 is rotated and conveyed, and the toner collected by the photoconductor cleaning device 63 is conveyed to the developing device 61 through the conveyance path case 88. Then, the screw 68 is rotated into the developing device 61. Thereafter, as described above, the two screws 68 are conveyed and circulated while being stirred together with the developer already in the developing device 61, supplied to the developing sleeve 65 and cut off by the doctor blade 73, and then the photoreceptor 40. And the latent image on the photoreceptor 40 is developed.

An image forming apparatus that uses electrophotography, and includes an image carrier that carries an image formed by an electrophotographic process. Here, the embodiment described above corresponds to an intermediate transfer belt as an intermediate transfer member.
Conventionally, fluorine-based resin, polycarbonate resin, polyimide resin, etc. have been used for intermediate transfer belts. However, in recent years, all belt layers and elastic belts with elastic members as part of the belt have been used. Has been. A color image is usually formed with four colored toners. On one color image, toner layers of 1 to 4 layers are formed. The toner layer receives pressure by passing through the primary transfer (transfer from the photoreceptor to the intermediate transfer belt) and the secondary transfer (transfer from the intermediate transfer belt to the sheet), and the cohesive force between the toners increases. When the cohesive force between the toners increases, the phenomenon of missing characters in the characters and missing edges in the solid portion image tends to occur. Since the resin belt has high hardness and does not deform in accordance with the toner layer, the toner layer is easily compressed, and the character dropout phenomenon is likely to occur. Recently, there is an increasing demand for forming full-color images on various papers, for example, Japanese paper, intentionally irregularities, and forming images on paper. However, a paper with poor smoothness is liable to generate toner and voids at the time of transfer, and transfer loss is likely to occur. When the transfer pressure at the secondary transfer portion is increased to improve the adhesion, the condensing power of the toner layer is increased, and the above-mentioned character void is generated. Accordingly, since the elastic belt has a lower hardness than the resin belt, the elastic belt is deformed corresponding to the toner layer and the paper having poor smoothness at the transfer portion. In other words, since the elastic belt deforms following local unevenness, the paper does not have excessive flatness and has good adhesion without excessively increasing the transfer pressure against the toner layer. The transfer image with excellent uniformity can be obtained.

  The elastic belt resin is polycarbonate, fluororesin (ETFE, PVDF), polystyrene, chloropolystyrene, poly-α-methylstyrene, styrene-butadiene copolymer, styrene-vinyl chloride copolymer, styrene-vinyl acetate copolymer. Styrene-maleic acid copolymer, styrene-acrylic acid ester copolymer (styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer, styrene-butyl acrylate copolymer, styrene-octyl acrylate) Copolymer, styrene-phenyl acrylate copolymer, etc.), styrene-methacrylate copolymer (styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-phenyl methacrylate copolymer). Etc.), Styrene-α-Chloracryl Styrene resins (monopolymers or copolymers containing styrene or styrene-substituted products) such as methyl acid copolymer, styrene-acrylonitrile-acrylic acid ester copolymer, methyl methacrylate resin, butyl methacrylate resin, acrylic acid Ethyl resin, butyl acrylate resin, modified acrylic resin (silicone-modified acrylic resin, vinyl chloride resin-modified acrylic resin, acrylic / urethane resin, etc.), vinyl chloride resin, styrene-vinyl acetate copolymer, vinyl chloride-vinyl acetate copolymer Coalesce, rosin modified maleic acid resin, phenol resin, epoxy resin, polyester resin, polyester polyurethane resin, polyethylene, polypropylene, polybutadiene, polyvinylidene chloride, ionomer resin, polyurethane resin, silicone resin, ketone resin, ethylene Down - can be used ethyl acrylate copolymer, xylene resin and polyvinyl butyral resin, polyamide resin, one kind or two kinds or more selected from the group consisting of modified polyphenylene oxide resin. However, it is natural that the material is not limited to the above materials.

  Elastic rubbers and elastomers include butyl rubber, fluorine rubber, acrylic rubber, EPDM, NBR, acrylonitrile-butadiene-styrene rubber natural rubber, isoprene rubber, styrene-butadiene rubber, butadiene rubber, ethylene-propylene rubber, ethylene-propylene ter Polymer, chloroprene rubber, chlorosulfonated polyethylene, chlorinated polyethylene, urethane rubber, syndiotactic 1,2-polybutadiene, epichlorohydrin rubber, ricone rubber, fluororubber, polysulfide rubber, polynorbornene rubber, hydrogenated nitrile rubber Selected from the group consisting of thermoplastic elastomers (for example, polystyrene, polyolefin, polyvinyl chloride, polyurethane, polyamide, polyurea, polyester, fluororesin). It is possible to use one kind or two or more kinds. However, it is natural that the material is not limited to the above materials.

  There are no particular restrictions on the conductive agent for adjusting the resistance value. For example, carbon black, graphite, metal powder such as aluminum or nickel, tin oxide, titanium oxide, antimony oxide, indium oxide, potassium titanate, antimony oxide-tin oxide composite Conductive metal oxides such as oxide (ATO), indium oxide-tin oxide composite oxide (ITO), and conductive metal oxides are coated with insulating fine particles such as barium sulfate, magnesium silicate, and calcium carbonate But you can. Of course, the conductive agent is not limited to the above.

  There is no limitation on the surface layer material, but a material that reduces the adhesive force of the toner to the transfer belt surface and increases the secondary transfer property is required. For example, materials that use one or more of polyurethane, polyester, epoxy resin, etc. to reduce surface energy and improve lubricity, such as fluororesins, fluorine compounds, fluorocarbons, titanium dioxide, silicon carbide, etc. , One kind or two or more kinds of particles or particles having different particle diameters can be dispersed and used. In addition, it is also possible to use a material having a reduced surface energy by forming a fluorine-rich layer on the surface by heat treatment, such as a fluorine-based rubber material.

  The method for manufacturing the belt is not limited. For example, a centrifugal molding method in which a material is poured into a rotating cylindrical mold to form a belt, a spray coating method to form a thin film on the surface, a dipping method in which a cylindrical mold is dipped in a solution of the material, an inner mold , There is a casting method to be injected into the outer mold, a method in which a compound is wound around a cylindrical mold and vulcanization polishing is performed, but this is not limited to this, and a belt is manufactured by combining a plurality of manufacturing methods. Of course you can.

The manufacturing method of the elastic belt used for the present Example is demonstrated. A cylindrical mold is immersed in a dispersion in which carbon black: 18 parts by weight, dispersant: 3 parts by weight, and toluene: 400 parts by weight are uniformly dispersed with respect to 100 parts by weight of PVDF, and gently lifted at 10 mm / sec to room temperature. And dried to form a uniform film of 75 μm PVDF. A mold on which a 75 μm film was formed was repeatedly immersed in a cylindrical mold in the solution under the above conditions, gently lifted at 10 mm / sec, and dried at room temperature to form a 150 μm PVDF belt. In addition, the above-mentioned 150 μm PVDF was dispersed in a dispersion obtained by uniformly dispersing polyurethane plastic polymer: 100 parts by weight, curing agent (isocyanate): 3 parts by weight, carbon black: 20 parts by weight, dispersant: 3 parts by weight, and MEK: 500 parts by weight. The cylinder was formed and dipped at 30 mm / sec and air dried. After drying, the process was repeated to form a target 150 μm urethane polymer layer. Further, 100 parts by weight of polyurethane prepolymer, 3 parts by weight of curing agent (isocyanate), 50 parts by weight of PTFE fine powder, 4 parts by weight of dispersant, and 500 parts by weight of MEK were uniformly dispersed for the surface layer.
The cylindrical mold on which the 150 μm urethane prepolymer was formed was dipped, pulled up at 30 mm / sec, and naturally dried. After drying, the process was repeated to form a urethane polymer surface layer in which 5 μm of PTFE was uniformly dispersed. After drying at room temperature, crosslinking was performed at 130 ° C. for 2 hours to obtain a three-layer transfer belt having a resin layer: 150 μm, an elastic layer: 150 μm, a surface layer: 5 μm.

As a method for preventing elongation by elastic belting, there are a method of forming a rubber layer in a core resin layer having a small elongation as in the above-mentioned embodiment, a method of putting a material for preventing elongation in the core layer, etc. It is not related to the manufacturing method. Examples of materials constituting the core layer for preventing elongation include natural fibers such as cotton and silk, polyester fibers, nylon fibers, acrylic fibers, polyolefin fibers, polyvinyl alcohol fibers, polyvinyl chloride fibers, polyvinylidene chloride fibers, One or two selected from the group consisting of synthetic fibers such as polyurethane fibers, polyacetal fibers, polyfluoroethylene fibers and phenol fibers, inorganic fibers such as carbon fibers, glass fibers and boron fibers, and metal fibers such as iron fibers and copper fibers A woven or thread-like material can be formed using more than one seed. Of course, the material is not limited to the above.
The yarn may be twisted in any manner, such as one or a plurality of filaments twisted, a single twisted yarn, various twisted yarns, a double yarn or the like. Further, for example, fibers of a material selected from the above material group may be blended. Of course, the yarn can be used after being subjected to an appropriate conductive treatment. On the other hand, the woven fabric can be any woven fabric such as knitted fabric, and of course, a woven fabric that is interwoven can also be used, and naturally conductive treatment can be applied.
The production method for providing the core layer is not particularly limited, for example, a method of providing a woven fabric woven in a cylindrical shape on a mold and the like, and providing a coating layer thereon, the woven fabric woven in a cylindrical shape is a liquid rubber And a method of providing a coating layer on one side or both sides of the core layer, and a method of winding a thread spirally around a mold at an arbitrary pitch and providing a coating layer thereon.

The thickness of the elastic layer depends on the hardness of the elastic layer, but if it is too thick, the surface expands and contracts and cracks are likely to occur in the surface layer. In addition, it is not preferable that the thickness is too large (e.g., about 1 mm or more) because the amount of expansion and contraction becomes large and the image is stretched.
An appropriate range of the hardness of the elastic layer is 10 ≦ HS ≦ 65 ° (JIS-A). The optimum hardness needs to be adjusted according to the belt layer thickness. Those having a hardness of less than 10 ° JIS-A are very difficult to mold with high dimensional accuracy. This is due to the fact that it is susceptible to shrinkage and expansion during molding. In order to make it softer, it is a general method to contain an oil component in the base material, but there is a drawback that the oil component begins to ooze out when continuously operated in a pressurized state. As a result, it has been found that the photosensitive member in contact with the surface of the intermediate transfer member is contaminated to generate horizontal band unevenness. In general, a surface layer is provided to improve releasability. However, in order to completely prevent the seepage, the surface layer has high required quality such as durability, and it is necessary to select materials and secure properties. It becomes difficult. On the other hand, those with a hardness of 65 ° JIS-A or higher can be molded with high accuracy as much as the hardness is increased, and the oil content can be suppressed or reduced, so the contamination on the photoreceptor is reduced. Although it is possible, the effect of improving the transferability such as character dropout cannot be obtained, and it becomes difficult to stretch the roller.

A method for manufacturing the elastic belt will be described. PVDF: 100 parts by weight Carbon black: 18 parts by weight, Dispersant: 3 parts by weight, Toluene: 400 parts by weight, a cylindrical mold is immersed in a dispersion, and gently lifted at 10 mm / sec. Was dried to form a uniform film of 75 μm PVDF. A mold on which a 75 μm film was formed was repeatedly immersed in a cylindrical mold in the solution under the above conditions, gently lifted at 10 mm / sec, and dried at room temperature to form a 150 μm PVDF belt. In addition, the above-mentioned 150 μm PVDF was dispersed in a dispersion in which polyurethane prepolymer: 100 parts by weight, curing agent (isocyanate): 3 parts by weight, carbon black: 20 parts by weight, dispersant: 3 parts by weight, and MEK: 500 parts by weight were uniformly dispersed. The cylinder was formed and dipped at 30 mm / sec and air dried. After drying, the process was repeated to form a target 150 μm urethane polymer layer.
Further, 100 parts by weight of polyurethane prepolymer, 3 parts by weight of curing agent (isocyanate), 50 parts by weight of PTFE fine powder, 4 parts by weight of dispersant, and 500 parts by weight of MEK were uniformly dispersed for the surface layer. The cylindrical mold on which the 150 μm urethane prepolymer was formed was dipped, pulled up at 30 mm / sec, and naturally dried. After drying, the process was repeated to form a urethane polymer surface layer in which 5 μm of PTFE was uniformly dispersed. After drying at room temperature, crosslinking was performed at 130 ° C. for 2 hours to obtain a three-layer transfer belt having a resin layer: 150 μm, an elastic layer: 150 μm, a surface layer: 5 μm.

Next, the characteristic part of this embodiment is demonstrated.
As a specific example, FIG. 7 is a schematic cross-sectional view showing a configuration of a conventional intermediate transfer belt cleaning device. Although the intermediate transfer belt cleaning device will be described here, it is needless to say that a photosensitive member cleaning device may be used.
The image is cleaned from the intermediate transfer belt 10 by the cleaning blade 101 with respect to the paper transfer residual toner attached to the intermediate transfer belt 10, the running state of the intermediate transfer body, and the alignment of each color. The toner cleaned by the cleaning blade 101 falls, is transported by the toner transport screw 103 provided in the case 102 of the cleaning device 17, and is sent to the waste toner transport path in the machine. Here, the cleaning blade 101 is a tension roller that gives an appropriate tension to the intermediate transfer member through the image bearing member. The positional relationship between the cleaning blade 101 and the tension roller 15 greatly affects the cleaning performance. This is because this positional relationship affects the cleaning angle and contact pressure of the leading edge portion of the cleaning blade 101.

As described above, the cleaning method generally involves scraping an image from an image carrier such as an intermediate transfer belt, a direct transfer belt, or a photoreceptor with a blade, a brush, etc., but these methods do not provide sufficient cleaning properties. In this case, a lubricant 181 such as a steering acid zinc pressed by a spring 183 or the like as a lubricant pressurizing member is shaved with a brush roller 182 or the like as a lubricant supply member to form a powder and applied to the surface of the photoreceptor 40 or the intermediate transfer belt 10. To do.
FIG. 8 is a diagram showing a change in the state over time when the lubricant is applied by the brush roller. By continuing to apply the lubricant 181, the lubricant 181 is scraped and the height of the lubricant is reduced. As a result, the spring 183 is extended, and the contact pressure by the spring 183 is smaller than that at the time of attachment, and the brush roller 182. The amount of the lubricant 181 to be polished is reduced, the application amount applied to the intermediate transfer belt 10 is reduced, and a sufficient μ reduction of the intermediate transfer belt 10 cannot be obtained. As a result, the cleaning properties differ greatly between the initial use and the passage of time.

9 and 10 are diagrams showing the configuration of the pressure holding mechanism provided in the cleaning device of the present invention. As in FIG. 7, when the lubricant 181 becomes smaller with time, the spring 183 is prevented from extending by pushing the base 185 with the cam 184 as a pressure holding mechanism, and the amount of extension of the spring 183 is offset by the cam 184. . As shown in FIG. 9, this allows the pressure at which the brush roller 182 contacts the lubricant to be always the same, the amount to be scraped to be the same, and the amount applied to the intermediate transfer belt to be always the same. . Thus, by changing the pedestal 185 so that the spring length is always constant, the lubricant contact pressure is always constant.
Also, as shown in FIG. 10, when the lubricant 181 becomes smaller with time, the spring 183 is prevented from extending by pressing the base 185 with an air spring 186 as a pressure holding mechanism, and the amount of extension of the spring 183 is offset. To do. As a result, the amount applied to the intermediate transfer belt can always be the same.

The operation of the cam 184 or the like as the pressure holding mechanism may be performed by a serviceman or a user during maintenance. Further, the image forming apparatus 100 main body may count the number of recording media that are conveyed and pass, and may be operated when a certain amount of recording media passes.
Further, a sensor may be arranged around the lubricant 181 and the spring 183 to detect the length of the spring 183 as a pressure member, and the cam 184 of the pressure holding mechanism may be operated according to the change. Further, the lubricant 181 is arranged vertically without being fixed, and a weight or the like is placed on the lubricant 181 and brought into contact with the brush roll 182, so that the lubricant 181 is brought into contact with the same weight even if the lubricant 181 is polished and shortened. be able to.
In the above embodiment, the present invention is applied to the transfer unit 6 in the tandem printer in which the photosensitive drums 40Y, 11M, 11C, and 11K are arranged side by side on the transfer conveyance belt 60. However, the present invention is applied. Possible image forming apparatuses and belt driving apparatuses are not limited to this configuration. In an image forming apparatus having a belt driving device that rotationally drives an endless belt stretched around a plurality of rollers by at least one of the rollers, any belt driving device can be applied. . As a result, the friction coefficients of the intermediate transfer belt and the photosensitive member can always be kept constant.

The toner used in each of the image forming units 18Y, 1M, 1C, and 1K has a volume average particle size of 3.0 to 8.0 μm, and has a volume average particle size (Dv) and a number average particle size (Dn). (Dv / Dn) is preferably in the range of 1.00 to 1.40. By narrowing the particle size distribution of the toner, the charge amount distribution becomes uniform and a high-quality image with little background fogging can be obtained. Further, since the transfer rate can be increased, the amount of untransferred toner in each image forming unit 18 can be reduced.
The volume average particle size (Dv) and the ratio (Dv / Dn) of the volume average particle size (Dv) to the number average particle size (Dn) are the Coulter Counter TA-II or Coulter Multisizer (Coulter Corporation). Can be used.

Further, the toner used in each of the image forming units 18Y, 1M, 1C, and 1K preferably 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.
FIG. 11 is a diagram schematically showing 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) (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 on the two-dimensional plane by the figure area AREA and multiplying by 100π / 4.
SF-2 = {(PERI) ² / AREA} × (100π / 4) Expression (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 between the toner and the toner or the toner and the photosensitive drum 40 is close to a point contact, so that the adsorbing force between the toners is weakened and the fluidity is increased. The attracting force with the photosensitive drum 40 is also weakened, and the transfer rate is increased. On the other hand, since spherical toner tends to enter the gap between the cleaning blades 75 and 101 and the photosensitive drum 40, the toner shape factor SF-1 or SF-2 is preferably large to some extent. Further, when SF-1 and SF-2 are increased, toner is scattered on the image and the image quality is lowered. For this reason, it is preferable that SF-1 and SF-2 do not exceed 180.

  The toner used in each image forming unit 18 is, for example, 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, examples of the constituent material and the manufacturing method of the toner will be described.

(Modified polyester)
The toner according to the present invention contains a modified polyester (i) as a binder resin. The modified polyester (i) refers to a state in which a bonding group other than an ester bond is present in the polyester resin, or resin components having different configurations are bonded to the polyester resin by a covalent bond, an ionic bond, or the like. Specifically, the polyester terminal is modified by introducing a functional group such as a carboxylic acid group or an isocyanate group that reacts with a hydroxyl group into the polyester terminal and further reacting with an active hydrogen-containing compound.

  Examples of the modified polyester (i) include urea-modified polyester obtained by a reaction between a polyester prepolymer (A) having an isocyanate group and amines (B). As the polyester prepolymer (A) having an isocyanate group, a polyester having a polycondensate of a polyhydric alcohol (PO) and a polyvalent carboxylic acid (PC) and having an active hydrogen group is further added to a polyvalent isocyanate compound (PIC). And those reacted with. Examples of the active hydrogen group possessed by the polyester include a hydroxyl group (alcoholic hydroxyl group and phenolic hydroxyl group), an amino group, a carboxyl group, a mercapto group, and the like. Among these, an alcoholic hydroxyl group is preferable.

The urea-modified polyester is produced as follows.
Examples of the polyhydric alcohol compound (PO) include dihydric alcohol (DIO) and 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 them, 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) with 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.

  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; 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 acid block of B1 to B5 (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.) and the like. 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 modified polyester (i) used in the present invention is produced by a one-shot method or a prepolymer method. The weight average molecular weight of the modified polyester (i) is usually 10,000 or more, preferably 20,000 to 10,000,000, more preferably 30,000 to 1,000,000. The peak molecular weight at this time is preferably 1000 to 10000. When the molecular weight is less than 1000, the elongation reaction hardly occurs, the elasticity of the toner is small, and as a result, the resistance to hot offset deteriorates. On the other hand, when it exceeds 10,000, the problem in production becomes high in the deterioration of fixability, particle formation and pulverization. The number average molecular weight of the modified polyester (i) is not particularly limited when the unmodified polyester (ii) described later is used, and may be a number average molecular weight that can be easily obtained to obtain the weight average molecular weight. (I) When used alone, the number average molecular weight is usually 20000 or less, preferably 1000 to 10000, and more preferably 2000 to 8000. When it exceeds 20000, the low-temperature fixability and the glossiness when used in a full-color device are deteriorated.
In the crosslinking and / or extension reaction between the polyester prepolymer (A) and the amines (B) to obtain the modified polyester (i), a reaction terminator is used as necessary to adjust the molecular weight of the resulting urea-modified polyester. be able to. Examples of the reaction terminator include monoamines (diethylamine, dibutylamine, butylamine, laurylamine, etc.), and those obtained by blocking them (ketimine compounds).
The molecular weight of the polymer produced can be measured using gel permeation chromatography (GPC) with THF as a solvent.

(Unmodified polyester)
In the present invention, not only the modified polyester (i) is used alone, but also the unmodified polyester (ii) can be contained as a binder resin component together with the (i). By using (ii) in combination, the low-temperature fixability and the gloss when used in a full-color device are improved, which is preferable to single use. Examples of (ii) include polycondensates of polyhydric alcohol (PO) and polyvalent carboxylic acid (PC) similar to the polyester component of (i), and preferred ones are also the same as (i). . (Ii) is not limited to unmodified polyester, but may be modified with a chemical bond other than a urea bond, and may be modified with a urethane bond, for example. It is preferable that (i) and (ii) are at least partially compatible in terms of low-temperature fixability and hot offset resistance. Accordingly, the polyester component (i) and (ii) preferably have similar compositions. When (ii) is contained, the weight ratio of (i) to (ii) is usually 5/95 to 80/20, preferably 5/95 to 30/70, more preferably 5/95 to 25/75, Particularly preferred is 7/93 to 20/80. When the weight ratio of (i) 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 peak molecular weight of (ii) is usually 1000 to 10,000, preferably 2000 to 8000, and more preferably 2000 to 5000. If it is less than 1000, heat-resistant storage stability will deteriorate, and if it exceeds 10,000, low-temperature fixability will deteriorate. The hydroxyl value of (ii) is preferably 5 or more, more preferably 10 to 120, and particularly preferably 20 to 80. If it is less than 5, it is disadvantageous in terms of both heat-resistant storage stability and low-temperature fixability. The acid value of (ii) is preferably 1 to 5, more preferably 2 to 4. Since a high acid value wax is used as the wax, the low acid value binder leads to electrification and high volume resistance, so that it is easy to match the toner used for the two-component developer.

The glass transition point (Tg) of the binder resin is usually 35 to 70 ° C, preferably 55 to 65 ° C. If it is less than 35 ° C., the heat resistant storage stability of the toner is deteriorated, and if it exceeds 70 ° C., the low-temperature fixability is insufficient. Since the urea-modified polyester is likely to be present on the surface of the obtained toner base particles, the toner of the present invention tends to have good heat storage stability even when the glass transition point is low, as compared with known polyester-based toners. Show.
The glass transition point (Tg) can be measured with a differential scanning calorimeter (DSC).

(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 Carmin Min BS, 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 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 resins, aromatic petroleum resins, chlorinated paraffins, paraffin waxes 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 , Phenolic condensate E-89 (above, Orient Chemical Industries, Ltd.), quaternary ammonium salt molybdenum complex TP-302, TP-415 (above, Hodogaya Chemical Co., Ltd.), quaternary ammonium salt copy Charge PSY VP2038, copy blue PR of triphenylmethane derivative, copy charge of quaternary ammonium salt NEG VP2036, copy charge NX VP434 (manufactured by Hoechst), LRA-901, LR-147 which is a boron complex (Nippon Carlit) Manufactured), copper phthalocyanine, perylene, quinacridone, azo series Fee, a sulfonic acid group, a carboxyl group, and polymer compounds having a functional group such as 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 flowability of the developer 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, 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 ~2μm, it is particularly preferably 5 × ¹⁰ -3 ~0.5μm. 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 diameter 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 to obtain a good image quality that does not cause the release of the fluidity imparting agent from the toner and does not generate firefly, etc., and further reduces the residual toner. It is done.
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 preferable. The usage-amount of an organic solvent is 1-300 weight part normally with respect to 100 weight part of polyester prepolymers, Preferably it is 1-100 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 20000 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 salt, dialkyldimethylammonium salt, alkyldimethylbenzylammonium salt, pyridinium salt, alkylisoquinolinium salt, benzethonium chloride, fatty acid amide derivative, polyhydric alcohol 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. Salt, benzalkonium salt, benzethonium chloride, pyridinium salt, imidazolinium salt, 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), SGP (manufactured by Soken), 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 Nitrogen compounds such as imidazole and ethyleneimine, or homopolymers or copolymers such as those having a heterocyclic ring thereof, polyoxyethylene, poly Xoxypropylene, polyoxyethylene alkylamine, polyoxypropylene alkylamine, polyoxyethylene alkylamide, polyoxypropylene alkylamide, polyoxyethylene nonylphenyl ether, polyoxyethylene lauryl phenyl ether, polyoxyethylene stearyl phenyl ester, polyoxy Polyoxyethylenes such as ethylene nonylphenyl ester, 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 sphere and the spindle shape can be controlled, and the surface morphology is also controlled between the smooth one and the umeboshi shape. Can do.

The shape of the toner is preferably a substantially spherical shape, and can be expressed by the following shape rule.
FIG. 12 is a diagram schematically showing the shape of the toner according to the present invention. In FIG. 12, when a substantially spherical toner is defined by a major axis r1, a minor axis r2, and a thickness r3 (where r1 ≧ r2 ≧ r3), the toner according to the present invention has a major axis and a minor axis. (R2 / r1) (see (b)) is 0.5 to 1.0, and the ratio of thickness to short axis (r3 / r2) (see (c)) is 0.7 to 1.0. It is preferable that it exists in the range. When the ratio of the major axis to the minor axis (r2 / r1) is less than 0.5, the dot reproducibility and transfer efficiency are inferior because of being away from the true spherical shape, and high-quality image quality cannot be obtained. On the other hand, if the ratio of thickness to minor axis (r3 / r2) is less than 0.7, the shape is close to a flat shape, and a high transfer rate like a spherical toner cannot be obtained. In particular, when the ratio of the thickness to the minor axis (r3 / r2) is 1.0, the rotating body has a major axis as a rotation axis, and the fluidity of the toner can be improved.
Note that r1, r2, and r3 were measured with a scanning electron microscope (SEM) while changing the angle of field of view and taking pictures.

The toner produced as described above can be used as a one-component magnetic toner that does not use a magnetic carrier or as a non-magnetic toner.
In addition, when used in a two-component developer, it may be used by mixing with a magnetic carrier, and the magnetic carrier is a ferrite containing a divalent metal such as iron, magnetite, Mn, Zn, Cu, A volume average particle size of 20 to 100 μm is preferred. If the average particle size is less than 20 μm, carrier adhesion is likely to occur on the photoreceptor 1 during development, and if it exceeds 100 μm, the miscibility with the toner is low and the charge amount of the toner is insufficient, resulting in poor charging during continuous use. Cheap. In addition, Cu ferrite containing Zn is preferable because of its high saturation magnetization, but can be appropriately selected according to the process of the image forming apparatus 100. The resin for coating the magnetic carrier is not particularly limited, and examples thereof include silicone resin, styrene-acrylic resin, fluorine-containing resin, and olefin resin. In the manufacturing method, the coating resin may be dissolved in a solvent, sprayed into a fluidized bed and coated on the core, or the resin particles are electrostatically attached to the core particles and then thermally melted for coating. It may be a thing. The resin to be coated has a thickness of 0.05 to 10 μm, preferably 0.3 to 4 μm.

In the above, as a best mode for carrying out the present invention, the transfer of the toner image formed by each image forming unit 18 is directly transferred to the recording medium conveyed by the transfer conveyance belt 3. Although an image forming apparatus is shown, an indirect transfer is provided that includes an intermediate transfer member such as an intermediate transfer belt 10 and transfers the toner image formed by each image forming unit 18 once to the intermediate transfer member and then secondary transfer to a recording medium. The present invention can be applied even to the image forming apparatus 100 of the type, and the same effect can be obtained.
Furthermore, at least a process cartridge that transports the cleaning device 63 that is transported into the cleaning device 63 in which the photosensitive drum 40 that forms a latent image, the cleaning blade 75, and the lubricant 201 is disposed, and is detachable from the main body of the image forming apparatus 100 is detachable. It is. As a result, the life of the photosensitive drum 40 accommodated in the process cartridge can be extended, and when the maintenance becomes necessary, the process cartridge can be replaced, and the convenience is improved.

1 is a schematic diagram illustrating a configuration of a tandem electrophotographic apparatus according to an embodiment of the present invention. 1 is a schematic view showing a configuration of a direct transfer tandem electrophotographic apparatus. 1 is a schematic diagram illustrating a configuration of an indirect transfer tandem electrophotographic apparatus. It is the schematic which shows the structure of the principal part of a tandem image forming apparatus. FIG. 3 is a schematic diagram illustrating a configuration of a toner recycling apparatus. FIG. 3 is a schematic diagram illustrating a configuration of a toner recycling apparatus. FIG. 10 is a schematic cross-sectional view illustrating a configuration of a conventional intermediate transfer belt cleaning device. It is a figure which shows the change of a state with time when apply | coating a lubricant with a brush roller. It is a figure which shows the structure of the pressure holding mechanism with which the cleaning apparatus of this invention is equipped. It is a figure which shows the structure of the pressure holding mechanism with which the cleaning apparatus of this invention is equipped. FIG. 6 is a diagram schematically illustrating the shape of a toner in order to explain the shape factor SF-1 and the shape factor SF-2. FIG. 3 is a diagram schematically illustrating the shape of a toner according to the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Intermediate transfer body 11 Surface layer 12 Elastic layer 13 Base layer 16 Cleaning blade 17 Intermediate transfer body cleaning apparatus 171 Cleaning blade 172 Case 173 Toner conveyance screw 181 Lubricant 182 Brush roller 183 Spring 184 Cam 185 Base 186 Air spring 18 Image forming unit 20 Tandem type image forming device 22 Secondary transfer device 24 Conveying belt 25 Fixing device 40 Photoconductor 42 Paper feed roller 50 Supply device 61 Development device 62 Primary transfer device 63 Photoconductor cleaning device 77 Metal electric field roller 100 Image forming unit 200 Paper unit 300 Scanner unit 400 Document transport unit

Claims (23)

A cleaning blade for cleaning the toner on the image carrier or intermediate transfer member;
In a cleaning device in which a brush roller for applying a lubricant of a lubricant molding to an image carrier or an intermediate transfer member is disposed,
The cleaning device includes:
A lubricant supply member for supplying a lubricant to the image carrier or the intermediate transfer member, a lubricant, and a lubricant pressure member for bringing the lubricant into contact with the lubricant supply member, and
A cleaning device comprising a pressure holding mechanism that keeps the pressure applied to the lubricant pressure member constant. The cleaning device according to claim 1,
The cleaning device according to claim 1, wherein the pressure holding mechanism keeps the applied pressure constant by a cam. The cleaning device according to claim 1,
The cleaning device according to claim 1, wherein the pressure holding mechanism keeps the applied pressure constant by an air spring. The cleaning device according to claim 2 or 3,
The cleaning device characterized in that the pressure holding mechanism is manually adjusted to keep the applied pressure constant. The cleaning device according to claim 2 or 3,
The pressure holding mechanism keeps the applied pressure constant in a stepwise manner depending on the number of sheets to be passed. The cleaning device according to claim 2 or 3,
The cleaning device according to claim 1, wherein the pressure holding mechanism detects the length of the lubricant pressure member and keeps the applied pressure constant. The cleaning device according to claim 2 or 3,
The pressure holding mechanism includes a pressure sensor disposed in the vicinity of the lubricant, thereby detecting the pressure between the lubricant and the image carrier that is in contact with the lubricant, and maintaining the applied pressure constant. . The cleaning device according to claim 2 or 3,
The cleaning device, wherein the lubricant comes into contact with the lubricant supply agent by its own weight. At least a process cartridge that includes an image carrier that carries a latent image and a cleaning device that cleans toner on the image carrier, and is detachable from the image forming apparatus main body.
The cleaning device includes a lubricant supply member that supplies a lubricant to the image carrier, a lubricant, and a lubricant pressure member that abuts the lubricant against the lubricant supply member, and the pressure applied to the lubricant pressure member is constant. A process cartridge characterized by having a pressure holding mechanism for maintaining the pressure. The process cartridge according to claim 9, wherein
The process cartridge according to claim 2, wherein the cleaning device is a cleaning device according to claim 2. An image carrier that carries a latent image, a charging device that charges the image carrier by bringing a charging member into contact with or close to the surface of the image carrier, a latent image forming device that forms a latent image on the image carrier, and an image carrier A transfer electric field is formed between the developing device for developing the toner by attaching the toner to the latent image on the body, and the intermediate transfer member and / or the recording member that moves while contacting the image carrier to form an image carrier. In an image forming apparatus comprising: a transfer device that transfers a formed toner image onto an intermediate transfer member and / or a recording member; and a cleaning device that cleans toner on the image carrier.
The cleaning apparatus includes a lubricant supply member that supplies a lubricant to the image carrier and / or the intermediate transfer member, a lubricant, and a lubricant pressure member that abuts the lubricant against the lubricant supply member. An image forming apparatus comprising: a pressure holding mechanism that keeps the pressing force of the pressing member constant. The image forming apparatus according to claim 11.
The image forming apparatus, wherein the cleaning device is the cleaning device according to any one of claims 2 to 8. The image forming apparatus according to claim 11.
The image forming apparatus comprises the process cartridge according to claim 10. The image forming apparatus according to claim 11,
The toner has a volume average particle diameter (Dv) in the range of 3 to 8 μm, and has a dispersity defined by a ratio (Dv / Dn) of the volume average particle diameter (Dv) to the number average particle diameter (Dn). An image forming apparatus having a range of 1.00 to 1.40. The image forming apparatus according to claim 14.
The image forming apparatus, wherein the toner has an average circularity in a range of 0.93 to 1.00. The image forming apparatus according to claim 14 or 15,
The image forming apparatus, wherein the toner has a shape factor SF-1 in a range of 100 to 180 and a shape factor SF-2 in a range of 100 to 180. The image forming apparatus according to any one of claims 14 to 16,
The toner has a substantially spherical appearance,
The ratio of the major axis to the minor axis (r2 / r1) is in the range of 0.5 to 1.0, and the ratio of the thickness to the minor axis (r3 / r2) is in the range of 0.7 to 1.0. An image forming apparatus characterized by satisfying a relationship of major axis r1 ≧ minor axis r2 ≧ thickness r3. The image forming apparatus according to any one of claims 14 to 17,
In the toner, a toner composition containing at least a polyester prepolymer having a functional group containing a nitrogen atom, a polyester, a colorant, and a release agent is crosslinked and / or extended in an aqueous medium in the presence of resin fine particles. An image forming apparatus. An image carrier that carries a latent image, a charging device that charges the image carrier by bringing a charging member into contact with or close to the surface of the image carrier, a latent image forming device that forms a latent image on the image carrier, and an image carrier The toner formed on the image carrier by forming a transfer electric field between the developing device for developing the toner by attaching the toner to the latent image on the body and the surface moving member that moves while contacting the image carrier. A transfer device for transferring an image onto a recording member or a surface moving member sandwiched between the surface moving member, a cleaning blade, a brush-like roller, and a lubricant molded body are disposed, and the brush-like roller is insulative. In a toner used for an image forming apparatus provided with a cleaning device that applies a lubricant of a lubricant molding to an image carrier and transports the toner cleaned by a cleaning blade to the inside of the cleaning device.
The toner has a volume average particle diameter (Dv) in the range of 3 to 8 μm, and has a dispersity defined by a ratio (Dv / Dn) of the volume average particle diameter (Dv) to the number average particle diameter (Dn). A toner having a range of 1.00 to 1.40. The toner according to claim 19,
The toner has an average circularity in a range of 0.93 to 1.00. The toner according to claim 19 or 20,
The toner is characterized in that it 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 toner according to any one of claims 19 to 21,
The toner has a substantially spherical appearance,
The ratio of the major axis to the minor axis (r2 / r1) is in the range of 0.5 to 1.0, and the ratio of the thickness to the minor axis (r3 / r2) is in the range of 0.7 to 1.0. And a toner satisfying the relationship of major axis r1 ≧ minor axis r2 ≧ thickness r3. The toner according to any one of claims 19 to 22,
In the toner, a toner composition containing at least a polyester prepolymer having a functional group containing a nitrogen atom, a polyester, a colorant, and a release agent is crosslinked and / or extended in an aqueous medium in the presence of resin fine particles. Toner.

Images