JP4668676B2 - Image forming apparatus - Google Patents

Description

  The present invention relates to an electrophotographic image forming apparatus such as a printer, a copying machine, and a facsimile, a developing device used therefor, and a process cartridge, and also relates to an image forming method applied thereto. .

  Developers used in electrophotography, electrostatic recording, electrostatic printing, and the like are once attached to, for example, an image carrier (typically a photoreceptor) on which an electrostatic image is formed in the development process. Then, after being transferred from the photoreceptor to a transfer medium such as transfer paper in the transfer step, it is fixed on the paper surface in the fixing step.

As a developer used in the development process, a two-component developer composed of a carrier and a toner and a one-component developer composed of only a toner without using a carrier (magnetic toner, non-magnetic toner) are known. Yes.
In the two-component development system, the developer deteriorates due to the toner particles adhering to the carrier surface, and the toner concentration in the developer decreases because only the toner is consumed. There is a disadvantage that the developing device is enlarged because it must be maintained at a constant rate.
On the other hand, the one-component development method does not have the above-mentioned drawbacks, and has an advantage such as downsizing of the apparatus, and the development method because it is easy to use in any environment (low temperature, low humidity, high temperature, high humidity). Is becoming mainstream.

Further, the one-component development method using a one-component developer is further classified into a magnetic one-component development method using a magnetic toner and a non-magnetic one-component development method using a non-magnetic toner. The magnetic one-component development system uses a developing sleeve provided with a magnetic field generating means such as a magnet inside, holds magnetic toner containing a magnetic material such as magnetite, and develops a thin layer with a layer thickness regulating member. In recent years, many printers have been put into practical use.
On the other hand, in the non-magnetic one-component development method, since the toner does not have a magnetic force, the toner supply roller or the like is pressed against the developing sleeve to supply the toner onto the developing sleeve, and the toner is electrostatically held, and the layer thickness It is developed with a thin layer by the regulating member, and has the advantage of being able to cope with colorization because it does not contain a colored magnetic material. Also, since a magnet is not used for the developing sleeve, the device is lighter and less expensive. In recent years, it has been put to practical use in small full-color printers and the like.

In the developing process, a developing device is generally used which includes a developing unit that develops a latent image on the image carrier and a toner cartridge that supplies toner to the developing unit. In other words, the toner flows backward, the amount of toner in the toner supply container decreases, and an abnormal image is generated.
In order to solve such a problem, for example, Patent Document 1 includes a developing unit that develops an electrostatic latent image on the photosensitive belt 1 with toner and a toner cartridge that supplies toner to the developing unit. In the detachable developing device, the toner cartridge is provided detachably with respect to the developing unit, and the toner in the toner cartridge is supplied to the developing unit through the toner replenishing port. Discloses a developing device provided with a check valve made of an elastic material for preventing the backflow of toner from the toner to the toner cartridge.

  In Patent Document 1, the backflow of toner from the developing device to the toner supply container is prevented, and abnormal image generation due to a decrease in the toner in the developing device can be prevented. There are also various problems due to the configuration incapable of moving to the supply container.

For example, a weakly charged toner tends to remain in the developing unit over time, and the toner in the developing unit cannot move to the toner supply container as in the developing device described in Patent Document 1. If there is no means for improving the charge amount difference between the toner in the developing section and the toner in the toner supply container, image defects and toner scattering occur.
In particular, when development is performed using a non-magnetic one-component developer, a toner having a small particle size and a high charge amount is preferentially used for development, and a low charge amount toner having a large particle size in the developing portion. However, a phenomenon called selective development tends to occur, and therefore, the problem of a difference in charge amount between the toner in the developing unit and the toner in the toner supply container becomes more serious.

  As means for imparting an appropriate amount of charge to the toner, a method of increasing the acid value of the binder resin in the toner (see, for example, Patent Document 2) has been conventionally proposed. However, increasing the acid value of the resin tends to give a charge amount, but has a problem of poor environmental stability. That is, the charge amount increases excessively under low temperature and low humidity, and the charge amount decreases under high temperature and high humidity, affecting the quality such as a decrease in image density and background stains.

  In addition, a method of imparting an appropriate charge amount to the toner by increasing the amount of addition of the charge control agent, which has been frequently used as one of the toner raw materials conventionally (see, for example, Patent Document 3). Has been. However, when the addition amount of the charge control agent is increased, the dispersibility of the charge control agent in the resin is deteriorated, and image quality deterioration such as background stains is caused in long-term use.

On the other hand, a method (for example, refer to Patent Document 4) in which an appropriate charge amount is imparted without adding any charge control agent has been proposed. This method is characterized in that the charge amount of the toner can be maintained only by attaching inorganic fine particles to the toner surface.
As described above, according to the inventions described in Patent Documents 2 to 4, it is possible to give a moderate charge amount to the toner and prevent the generation of weakly charged toner to some extent. It is difficult to completely suppress the difference in charge amount in the supply container.

JP 2002-162817 A JP 2000-227676 A JP 2004-354530 A JP 2003-280256 A

  Therefore, the present invention has been made in view of the above circumstances, and the problem is that a developing device that suppresses toner chargeability and fluidity deterioration even in long-term use and a high-quality image over a long period of time by using this developing device. It is an object of the present invention to provide an image forming apparatus capable of obtaining the image.

The features of the present invention, which is a means for solving the above problems, are listed below.
1. The present invention includes at least a latent image carrier and a developing device that forms and develops a toner image on the latent image carrier and fixes the toner image on a fixing medium. The apparatus includes at least a developing unit that supplies toner to an image forming unit, a cartridge unit that supplies toner to the developing unit, and a hopper unit that temporarily stores toner supplied from the cartridge unit to the developing unit. And a developing device in which a part of the toner in the hopper can be returned to the cartridge part through a supply hole provided in an inner wall separating the cartridge part and the hopper part, and the cartridge The unit includes at least a rotating body that stirs / moves the toner, and a return that contacts the rotating body and promotes the return of the toner to the inside of the cartridge. Comprising advancing means, wherein the rotary member is made from a single film which can be bent, the return facilitating means is a plate-like member provided in the cartridge inner wall, the said film is rotated When hitting the plate-like member, the toner is blocked by the plate-like member to form a toner-free space between the plate-like member and the film, and a part of the toner in the hopper moves to the space. As a result, a part of the toner in the hopper part is returned into the cartridge part, and inorganic fine particles having at least two kinds of particle sizes are adhered to the toner surface. particle size is 30~80m ² / g and 100 to 250 m ² / g in BET specific surface area, the addition amount of each particle size of the inorganic fine particles, the toner base 100 parts by weight 0.1 The total amount of the inorganic fine particles added is 1.3 to 3.2 parts by weight with respect to 100 parts by weight of the mother base, and the toner is a cylindrical container without an upper bottom. One of two points at both ends of the top of the toner pile formed by lifting the cylindrical container and separating the toner from the cylindrical container after the toner is placed in The powder wall collapse angle formed by a line segment connecting one point located on the side closer to the one point of the top of the two points of the mountain skirt and a line segment connecting the two points of the mountain skirt is 30 ° to An image forming apparatus having an angle of 70 °.
2. The image forming apparatus of the present invention, 1. In the invention described in item 1, the developing device uses a toner having a cohesion degree of 6% to 15%.
3. The image forming apparatus of the present invention, 1. Or 2. In the invention described in item 1, the developing device uses toner having a loose apparent density in the range of 0.35 to 0.50.

4). In addition, the developing device of the present invention primarily includes at least a developing unit that supplies toner to the image forming unit, a cartridge unit that supplies toner to the developing unit, and toner that is supplied from the cartridge unit to the developing unit. A developing device having a hopper portion stored in the wall, wherein the wall existing between the chamber of the cartridge portion and the chamber of the hopper portion has a replenishing hole, and the toner in the hopper portion is formed from the replenishing hole. In the developing device in which a part of the cartridge unit can be returned to the cartridge unit, the cartridge unit includes at least a rotating body that stirs / moves the toner, and contacts the rotating body to return the toner to the inside of the cartridge unit. A return promoting means for promoting the rotating body, wherein the rotating body is made of a single bendable film, and the return promoting means comprises the cartridge. A plate-like member provided on the inner wall of the part, and when the film rotates and hits the plate-like member, the toner is blocked by the plate-like member, and toner is placed between the plate-like member and the film. A space that does not exist is formed, and a part of the toner in the hopper moves to the space, whereby a part of the toner in the hopper is returned to the cartridge, and at least two types of toner are formed on the toner surface. inorganic fine particles is being deposited having a particle size, the particle size of the two kinds of inorganic fine particles is 30~80m ² / g and 100 to 250 m ² / g in BET specific surface area, the particle diameter of the inorganic fine particles The added amount is 0.1 to 3.0 parts by weight with respect to 100 parts by weight of the toner base, and the total amount of the inorganic fine particles added is 1.3 to 3.3 with respect to 100 parts by weight of the toner base. 2 parts by weight The toner is placed in a cylindrical container without an upper bottom, and after standing, the cylindrical container is lifted and the toner is separated from the cylindrical container. A line segment connecting one of the two points on both ends and a point located on the side closer to the one point on the top of the two points on the peak of the toner, and a line connecting the two points on the peak Konakabe collapse angle formed between the, you being a 30 ° to 70 °.

5. An image bearing member on which an electrostatic latent image is formed and a developing device that develops the electrostatic latent image formed on the surface of the image bearing member with a developer containing toner and forms a toner image are integrally supported. In the process cartridge formed detachably on the image forming apparatus main body,
The developing device according to claim 4, wherein the developing device is a developing device according to claim 4.
A process cartridge characterized by that.

  By the means for solving the above, the image forming apparatus of the present invention, and the developing device and process cartridge used in the image forming apparatus can be used with a stable toner charge amount even in long-term use. In addition, the occurrence of toner scattering can be suppressed. In addition, since the decrease in toner fluidity can be suppressed, the toner can be stably supplied to the developing sleeve, whereby an image having a high density can be stably obtained over a long period of time.

(First embodiment)
FIG. 1 is a diagram showing a schematic configuration of a developing device 30 according to the first embodiment of the present invention.
The developing device 30 includes a developing unit 31 that develops the latent image of the photoconductor 11 as an image carrier with toner as a developer, and a toner cartridge 32 that replenishes the developing unit 31 with toner.
The developing unit 31 faces the photoconductor 11 and supplies a toner onto the developing sleeve 31a, which is a developer carrying member that conveys the toner to a developing area formed between the developing unit 31 and the developing sleeve 31a. Supply roller 31b, a regulation roller 31c that is a layer thickness regulating member that regulates the amount of toner on the developing sleeve 31a, and a first conveyance paddle 31d that conveys toner. The developing unit 31 includes a developing hopper 311 that temporarily stores toner supplied from the toner cartridge 32.
FIG. 2 is a diagram schematically illustrating the internal configuration of the toner cartridge 32 and the developing hopper 311 of the developing device 30 according to the first embodiment.
The toner cartridge 32 includes first and second storage chambers 321 and 322 that store toner, second and third transport paddles 32a and 32b that transport the toner to the developing unit 31, and a second transport paddle 32a. A protruding rib 35 is provided at the bottom of the toner cartridge 32 where the toner cartridge rotates.
Here, a one-component developer is used as the developer. In contrast to replacing the developer as will be described later, it is very difficult to separate the toner from the carrier once mixed with the two-component developer. In the case of a one-component developer, the developer in the toner cartridge 32 and the developing unit 31 is basically the same and can be replaced, and can be applied to the developing device 30 of the present invention. In particular, it is preferable to use a non-magnetic one-component developer even for a one-component developer. In the non-magnetic one-component developer, the external additive on the toner surface has a great influence on the chargeability and fluidity of the toner. In a magnetic one-component developer, developability can be controlled by the strength of magnetization depending on the amount of magnetic material. In the non-magnetic one-component developer, the developability is greatly influenced by the charge amount and fluidity due to the external additive. Therefore, when used in the developing device 30 of the present invention, a stable toner surface state can be obtained.

In the developing device 30, the developing unit 31 and the toner cartridge 32 are arranged in parallel in the horizontal direction. Further, the toner cartridge 32 and the developing unit 31 are provided with a supply hole 33 (hereinafter referred to as a communication port) through which the toner passes between the toner cartridge 32 and the developing unit 31.
The developing device 30 of the present invention allows the toner to pass through this communication port. As a result, the toner consumed in the developing unit 31 is replenished from the toner cartridge 32 to the developing unit 31, and the toner deteriorated in the developing unit 31 is transferred from the developing unit 31 to the toner cartridge 32 through this communication port. The toner is returned (hereinafter sometimes referred to as “discharge”). The toner cartridge 32 can be replaced independently of the developing unit 31 independently.
The toner is subjected to a pressing force by the toner supply roller 31b and the regulating roller 31c in the developing unit 31. By receiving this pressing force, irregularities on the surface of the toner are chipped and the surface becomes smooth, and the adhesion to the photoconductor increases, making cleaning difficult. For this reason, when the environment is low, cleaning failure may occur, and transferability is improved. However, fogging appears on a white background portion that has not been visually observed even if it is conventionally transferred. Further, when the toner is pressed, the external additive present on the toner surface is buried inside the toner. This will be described in detail later regarding the external additive, but the external additive has a higher hardness than the toner. For this reason, the toner is buried inside the toner. As the external additive present on the toner surface decreases, the chargeability of the toner changes. In particular, since silica used as an external additive has a large specific surface area, the charge amount is high, and the charge amount of the toner varies greatly depending on the amount of the external additive on the toner surface due to burying. Another effect is that the fluidity of the toner is reduced by burying the external additive. This fluidity indicates the adhesion force of the toner, and is present between the toner and, for example, the photoreceptor, and reduces the adhesion force therebetween. Similarly, the developability is improved by reducing the adhesion between the developing sleeve 31a and the toner. On the contrary, if the amount of the external additive existing on the toner surface is reduced due to the embedding, the developability is lowered.
Further, when toner is used as a non-magnetic one-component developer, selective development in which toner with a small particle diameter is preferentially supplied onto the developing sleeve by the toner replenishing roller is performed. For this reason, a large amount of deteriorated toner remains in the developing hopper before new toner is supplied from the toner cartridge, causing image deterioration, toner scattering, and the like.

  Therefore, in the developing device 30 of the present invention, the toner in the developing unit 31 is temporarily supplied to the toner cartridge 32 through the communication port 33 for supplying the toner consumed in the developing unit 31 from the toner cartridge 32 to the developing unit 31. The toner cartridge 32 is discharged and mixed with non-deteriorated toner in the toner cartridge 32 to reduce the existence ratio of the deteriorated toner amount, and then is supplied to the developing unit 31 through the communication port 33 and replenished. .

FIG. 3 is a diagram illustrating the movement of the toner in the toner cartridge 32 accompanying the rotation of the second transport paddle 32a.
The toner cartridge 32 is transported to the first storage chamber 321 by the third transport paddle of the second storage chamber 322, and further transported to the developing unit 31 side by the second transport paddle 32a.
The second transport paddle 32a is provided with a single paddle film (blade) configured to be bendable. By rotating this film, the curved leading end of the film scrapes off the toner and moves it toward the developing unit 31 side. Transport. Further, by providing the rib 35 in the first storage chamber 321, as shown in FIG. 3, when the previous paddle film hits the rib 35, the toner is blocked by the rib 35, and the rib 35 and the paddle A space P without toner is formed between the film for use. The space P is gradually filled by the intrusion of toner having good fluidity, but for a certain period of time, a space is formed on the lower side in the rotational direction of the paddle film of the second transport paddle 32a (FIG. 3 ( Refer to b).
3B, when the second transport paddle 32a rotates first, the toner is pushed into the developing unit 31 side by the paddle film, and from the toner cartridge 32 side through the communication port 33. It moves to the 31 side and is supplied. On the other hand, in the space P formed by the paddle film of the second transport paddle 32a and the rib 35 in the vicinity of the communication port 33 of the toner cartridge 32, the toner agitated by the first transport paddle 31d from the developing hopper 311 side. Move. As described above, the space P is formed by the paddle film and the ribs 35 of the second transport paddle, so that the return of the toner from the developing unit 31 to the toner cartridge 32 is promoted.

  By the way, the volume of the space P gradually decreases as toner with high fluidity enters. In the toner cartridge 32, the space P maintains a sufficient volume for a certain period of time, and in order to return the toner into the toner cartridge 32 for lubrication, the fluidity of the toner is suppressed to some extent, and a certain hardness is achieved. The powder wall collapse angle as an index indicating the fluidity of the toner is preferably 30 ° to 70 °.

(Powder wall collapse angle)
The powder wall collapse angle can be measured as follows. FIG. 4 is a diagram for explaining a method for measuring the powder wall collapse angle of toner. Put 10 g of toner in a cylindrical glass container with a diameter of 3 cm and a height of 7 cm, cover and set on a shaker (Model-YS-8D manufactured by Yayoi Co., Ltd.), with a stroke width of 80 mm and a stroke number of 100 times / min. Shake for 1 minute. After giving the toner a certain level of fluidity by the above operation, the following operations are performed. For subsequent operations, a powder tester (PT-N type manufactured by Hosokawa Micron Corporation) is used. After attaching the angle-of-repose measuring accessory, a cylindrical glass container (hereinafter referred to as a cylinder) having a diameter of 3 cm and a height of 5 cm without an upper bottom is placed on the accessory and the above-mentioned total amount of toner is poured. After standing for 1 minute, the cylinder is lifted vertically at 3 cm / sec to separate the cylinder from the toner. The base angle ∠ ABC or ∠ ACB of the triangle connecting the apex A and the crests B and C of the toner crest thus formed is defined as the powder wall collapse angle, and this angle is measured.
That is, the ease of collapse of the toner is defined by the angle of the inclined surface of the mountain of the toner powder. The angle is automatically measured by setting the angle of repose measurement arm to the position of ∠ABC or ∠ACB.

As described above, by using toner whose fluidity is suppressed to some extent, when the paddle film of the second transport paddle rotates at the tip of the rib, the rib 35 becomes an obstacle and the toner is not transported. Since the space P is maintained in a state having a sufficient volume, the toner is returned from the developing hopper 311 to the toner cartridge 32 for lubrication.
When the powder wall collapse angle is less than 30 °, the fluidity of the toner is too high, so that a sufficient space volume cannot be secured in the toner in the cartridge. On the other hand, if the powder wall disintegration angle is larger than 70 °, the fluidity of the toner is not sufficient, so that a stable development state cannot be obtained.

(Degree of aggregation)
The toner of the present invention preferably has a cohesion degree of 6 to 15%. The degree of aggregation is an index for measuring the cohesiveness between powders, and the lower the value, the harder it is to aggregate. Generally, there is a correlation with the fluidity of the powder, and the lower the degree of aggregation, the better the fluidity of the powder.
If the degree of aggregation is less than 6%, the fluidity of the toner is too high, so that a sufficient space cannot be secured in the toner in the cartridge. On the other hand, when the degree of aggregation exceeds 15%, the fluidity of the toner is not sufficient, and a stable development state cannot be obtained.

  In the present invention, the cohesiveness and fluidity are evaluated by setting a sieve on a vibrating table in the order of 400 mesh, 200 mesh, and 100 mesh using a powder stator vibratory sieve machine manufactured by Hosokawa Micron. Gently place 2 g of toner on this layered sieve and then apply vibration for 10 seconds. Thereafter, the mass of the toner remaining on each sieve is measured, and the degree of aggregation is obtained by the following formula (1).

(Loose apparent density)
In the toner of the present invention, the fluidity is controlled by performing the toner treatment after applying the external additive under a certain condition and controlling the adhesion rate of the external additive within the above range.
Specifically, the toner of the present invention is a toner having a loose apparent density in the range of 0.38 to 0.43. The loose apparent density is a density in a state in which the toner is sieved and the sieve is removed, and represents the fluidity of the toner. In the present invention, the loose apparent density is a powder tester (PT-N type, manufactured by Hosokawa Milon Co., Ltd.), a 246 μm sieve is set on the shaking table, 250 cc of the sample is placed therein, vibrated for 30 seconds, and attached. Scrape off excess toner on the cup with the blade and measure the weight. This operation is repeated 5 times, and the average value is taken as the measured value. In the PT-N type, the measured value is automatically displayed. Loose apparent density = weight (g) / volume of cup (100 cc).

  Here, the developing device will be further described in detail. The developing device 30 includes a developing sleeve 31a that rotates while carrying toner on the surface to develop an electrostatic latent image on the surface of the photoreceptor belt 11, and a toner first conveyance paddle 31d that rotates to pump up and stir the toner. The developing unit 31 includes a developing hopper 311 that temporarily stores the toner supplied from the toner cartridge 32, and the toner cartridge 32 that stores the toner (see FIG. 1). The reason why it is divided into two units in this way is that the developing unit 31 has durability that can withstand even if the toner cartridge 32 is replaced several times.

  The developing device 30 conveys the toner to the developer supply roller 31b while stirring the toner with the first conveyance paddle 31d in the developing unit 31, and the toner is simultaneously rubbed while the supply roller 31b rubs against the developing sleeve 31a. The toner is charged by friction charging. The charged toner is attracted to the developing sleeve 31a with a mirror image force and conveyed. Thereafter, the amount of toner conveyed to the development area is regulated by the regulation roller 31c. The thin toner layer formed on the developing sleeve 31a is developed on the photosensitive belt (see FIG. 8) with a developing bias in the developing region.

At this time, the toner rubbed against the developing sleeve 31a by the supply roller 31b receives a large pressing force, and the irregularities on the surface of the toner are scraped to become spherical and increase the adhesion force of the toner. Further, the external additive on the surface of the toner is buried by this pressing force and the fluidity is lowered, and further, the charge amount cannot be adjusted by the external additive, so that the charge amount is changed. Under these influences, the developing property of the toner is lowered, and further, the transfer property and the cleaning property are lowered.
Thus, the amount of deteriorated toner increases in the developing hopper, and the toner in the developing unit 31 decreases because the toner is consumed by development. Therefore, the toner is supplied from the toner cartridge 32 to the developing unit 31 through the communication port 33. In the toner cartridge 32, a second transport paddle 32a and a third transport paddle 32b whose tips are in sliding contact with the inner wall of the toner cartridge main body 32 are provided in the first storage chamber 321 and the second storage chamber 322, respectively. Alternatively, the third transport paddles 32 a and 32 b rotate to push the toner into the developing unit 31, and the toner is supplied to the developing unit 31 from the communication port 33.

Further, the toner in the developing unit 31 is discharged to the toner cartridge 32 through the communication port 33, and the toner is mixed with the toner in the toner cartridge 32.
A large amount of unused toner is stored in the toner cartridge 32 and is mixed with the deteriorated toner in the developing unit 31. As a result of this mixing, the external additives that are present on the surface of unused toner are redistributed to deteriorated toner. By reducing the particle size, the charge amount and fluidity of the deteriorated toner become close to those of the original unused toner.
This is because the toner discharged from the developing unit 31 to the first storage chamber 321 is further transported to the second storage chamber 322 by the second transport paddle, and then to the first storage chamber 321 by the third transport paddle. Returned. During this time, the external additive is redistributed.
The toner approaching the original unused state is supplied again from the first storage chamber 321 of the toner cartridge 32 to the developing unit 31. A high-quality image can be obtained over a long period of time by forming a thin layer on the developing sleeve 31a and developing the toner with the toner that has approached the original state and the unused toner.

(Second embodiment)
Further, the developing device may be provided with a control valve 34 in the vicinity of the communication port 33.
FIG. 5 is a diagram showing a schematic configuration of a developing device 30 ′ according to the second embodiment of the present invention.
In the developing device 30 ′ according to the second embodiment, a control valve 34 is provided in the vicinity of the communication port 33 of the developing unit 31. Then, the supply of toner from the toner cartridge 32 to the developing unit is promoted by contact or separation between the control valve 34 and the paddle film of the first transport paddle.
Further, the communication port 34 is closed or opened by the control valve 34, so that toner is supplied from the toner cartridge 32 to the developing hopper 311 and toner is supplied from the developing hopper 311 to the toner cartridge 32. Return can be controlled.

FIG. 6 is a schematic view showing the structure of the control valve 34 disposed in the developing unit 31 in the developing device of the present invention. The control valve 34 is provided corresponding to the communication port 33 of the developing unit 31, and the control valve 34 is attached to the support portion 34a and disposed in the housing. As shown in FIG. 6, the control valve 34 has a rectangular shape corresponding to each communication port 33, and the portions without the communication port 33 are alternately provided without the control valve 34. The support portion 34a is made of a metal having rigidity and uses SUS, Cu, or Al. The control valve 34 is an elastic resin film 34b and uses polypropylene, polyethylene, polyester resin, or fluororesin.
The first transport paddle 31d of the developing unit 31 includes a paddle film. This film may be a single film or a plurality of films. The first transport paddle 31d rotates and supplies the toner supplied from the toner cartridge 32 side to the developing sleeve 31a. The film may be plate-shaped. In addition, for the comb-like rectangular control valve 34 provided corresponding to the communication port 33, only the portion corresponding to the control valve 34 may be rectangular. Moreover, when providing two or more sheets, you may use combining these.

FIG. 7 is a diagram schematically illustrating a state in which toner is supplied from the toner cartridge 32 side to the developing unit 31 in the developing device 30 ′ according to the second embodiment.
The first transport paddle 31d rotates to hit the control valve 34, and the control valve 34 is pressed. Thereafter, the first transport paddle 31d passes, and the elastic control valve 34 is quickly bounced back, and at the same time, the toner pushed in from the toner cartridge 32 side passes through the communication port 33 and the developing unit 31. The toner is supplied by being attracted to the side.

Further, in the developing device 30 ′ according to the second embodiment of the present invention, the paddle film of the second transport paddle 32a is formed by the paddle film of the second transport paddle 32a and the rib 35 in the same manner as shown in FIG. A section P is formed on the lower side in the rotation direction (FIG. 3B).
In the developing device 30 ′ according to the second embodiment, when the second transport paddle 32a further rotates from the state shown in FIG. 3B, the paddle film pushes the toner into the developing unit 31 side. And when the control valve 34 of the developing unit 31 is not pressed by the paddle film of the first transport paddle 31d and the control valve 34 is opened (when it is in a fixed position). The toner moves from the toner cartridge 32 side to the developing unit 31 side through the communication port 33 and is supplied.
Next, the toner in the developing unit 31 enters the opened control valve 34. After that, the paddle film of the first transport paddle 31d rotates and the toner that pushes the control valve 34 is pushed from the developing unit 31 side to the toner cartridge 32 side and the paddle for the second transport paddle in the first storage chamber 321. A space is formed inside the toner by the film, and the toner is moved and discharged from the developing unit 31 side to the toner cartridge 32 side through the communication port 33 by overlapping when the space reaches the communication port 33.

The movement of the first, second, and third transport paddles and the toner movement between the developing unit 31 and the toner cartridge 32 in the developing device 30 ′ at this time will be described in more detail.
FIG. 8 is a view schematically showing toner movement between the developing unit 31 and the toner cartridge 32 in the developing device 30 ′. Here, the developing sleeve 31a and the like in the developing unit 31 are omitted.
In the developing device 30, as shown in FIG. 6 (1), the control valve 34 in the developing unit 31 has a predetermined angle θ with respect to the wall surface provided with the communication port 33.
The first transport paddle 31d rotates a plurality of paddle films. The second and third transport paddles in the toner cartridge 32 rotate a single paddle film. As shown in FIG. 8 (2), in the developing unit 31, a plurality of paddle films push the control valve 34 in the first transport paddle 31 d, and at this time, the first transport paddle 31 d is between the control valve 34 and the communication port 33. Since the toner cartridge 32 side is also filled with toner, the toner cannot move through the communication port 33 and returns from the control valve 34 in the developing unit 31 into the developing unit 31 in the lateral direction. Next, as shown in FIG. 8 (3), in the first transport paddle 31 d, a plurality of paddle films push the control valve 34 further, and there is almost no gap between the control valve 34 and the communication port 33 ( (Operating position). Next, as shown in FIG. 8 (4) and FIG. 8 (5), the first transport paddle 31d has the control valve 34 returned to the original angle as the plurality of paddle films are separated from the control valve 34. Sometimes, a large gap is formed, and the toner is moved and supplied from the toner cartridge 32 side through the communication port 33 by forming a space.
Furthermore, as shown in FIG. 8 (6), the paddle film of the first transport paddle 31d pushes the control valve 34 again by having a plurality of sheets. At this time, the paddle film of the second transport paddle is in contact with the rib 35 in the second storage chamber 322 in the toner cartridge 32. When further rotated, as shown in FIG. 8 (7), the paddle film of the first transport paddle 31 d further pushes the control valve 34, and a state without a gap is formed between the control valve 34 and the communication port 33. At this time, when the paddle film of the second transport paddle is rotated first from the rib 35, the rib 35 becomes an obstacle and the toner is not transported. Therefore, the paddle film of the second transport paddle is placed in the toner cartridge 32. A space is formed in the lower direction of rotation. Further, as shown in FIGS. 8 (8) and 8 (9), the first transport paddle 31 d has a plurality of paddle films separated from the control valve 34, so that the control valve 34 returns to the original angle (fixed position). At this time, by forming a space with a large gap, the toner lifted by the paddle film of the second transport paddle 34a is further supplied from the toner cartridge 32 side through the communication port 33. Is done.

  However, next, as shown in FIG. 8 (10), the paddle film of the first transport paddle 31d pushes the control valve 34 again by having a plurality of sheets. Until now, there has been toner in the vicinity of the communication port 33 on the toner cartridge 32 side. However, if there is a space formed below the paddle film in the rotation direction of the paddle film of the second transport paddle 32a, Instead of returning from the control valve 34 in the lateral direction into the developing unit 31, it moves from the developing unit 31 side to the toner cartridge 32 side through the communication port 33 and is discharged. As shown in FIGS. 8 (11) and 8 (12), the paddle film of the first transport paddle 31d pushes the control valve 34 again, and further from the developing unit 31 side to the toner cartridge 32 side. It is moved and discharged.

At this time, if the fluidity of the toner is too high, the toner around the space P flows into the space P formed in the vicinity of the communication port 33 in the state shown in FIGS. Can not maintain a sufficient volume. For this reason, it is desirable that the toner has a certain degree of fluidity in which the fluidity is suppressed to some extent, and the powder wall disintegration angle as an index indicating the fluidity of the toner is preferably 30 ° to 70 °. .
Note that the powder wall collapse angle can be measured by the same method as described above.

Further, by making the rotation speed of the first transport paddle 31d faster than that of the second transport paddle, as shown in FIG. 8 (13) to FIG. It can be discharged.
By repeating this, the toner can be moved through the communication port 33 between the developing unit 31 and the toner cartridge 32.

Here, by controlling the rotational speeds of the first transport paddle 31d in the developing unit 31 and the second transport paddle 32a in the toner cartridge 32, the supply / discharge amount due to the movement of the toner can be adjusted. In particular, by making the rotation speed of the first transport paddle 31d in the developing unit 31 faster than the second transport paddle in the toner cartridge 32, the number of times the space formed inside the toner contacts the communication port 33 can be reduced. By increasing the number of times the first transport paddle 31d pushes the control valve 34, the number of times of supplying the toner through the communication port 33 can be increased.
Further, the amount of supply / discharge due to the movement of the toner can be adjusted by the number of communication ports 33, and therefore one or more communication ports 33 can be provided. The number of the communication ports 33 is appropriately determined according to the image forming speed of the image forming apparatus main body.

The image forming apparatus according to the present invention will be described in detail below.
FIG. 9 is a schematic diagram showing the configuration of the image forming apparatus of the present invention. The image forming apparatus 1 includes a photosensitive unit 10, a writing optical unit 20, a developing unit 30, an intermediate transfer unit 40, a secondary transfer unit 50, a fixing unit 60, a duplex printing paper reversing unit 70, and the like. Then, black (hereinafter referred to as Bk), cyan (hereinafter referred to as C), magenta (hereinafter referred to as M), and yellow (hereinafter referred to as Y) color images are successively developed on the photoreceptor belt 11 of the photoreceptor unit 10. These are then superimposed to form the final four-color full color image. Around the photoreceptor belt 11, a photoreceptor cleaning device 12, a charging roller 13, a plurality of developing devices 30, an intermediate transfer belt 41 of an intermediate transfer unit 40, and the like are disposed. The photosensitive belt 11 is stretched between a driving roller 14, a primary transfer counter roller 15, and a stretching roller 16, and is rotated by a driving motor. The writing optical unit 20 converts the color image data into an optical signal, performs optical writing corresponding to each color image, and forms an electrostatic latent image on the photosensitive belt 11. The writing optical unit 20 includes a semiconductor laser 21 as a light source, a polygon mirror 22, three reflecting mirrors 23, and the like.
The developing device 30 includes, in order from the lower side of the main body of the image forming apparatus 1, a Bk developing device 30K containing black toner, a C developing device 30C containing cyan toner, an M developing device 30M containing magenta toner, and a yellow. A Y developing device 30Y containing toner is provided. Here, a contact / separation mechanism for moving the developing devices in the left-right direction in the drawing to perform the contact / separation operation with respect to the photosensitive belt 11 is further provided.

  The toner in the developing device 30 is charged to a predetermined polarity, and a developing bias is applied to the developing sleeve 31 a by a developing bias power source, and the developing sleeve 31 a is biased to a predetermined potential with respect to the photosensitive belt 11. The contact / separation mechanism moves the developing device 30 toward the photosensitive belt 11 by the driving force when an electromagnetic clutch (not shown) for transmitting driving from the motor to each developing device 30 is turned on. At the time of development, any one selected from the developing device 30 moves and contacts the photosensitive belt 11. On the other hand, when the electromagnetic clutch is turned off and the drive transmission is released, the developing device that has been in contact with the photosensitive belt 11 moves away from the photosensitive belt 11.

In the standby state of the main body of the image forming apparatus 1, the developing devices 30K, C, M, and Y are also set at positions separated from the photosensitive belt 11, and when the image forming operation is started, the laser beam is based on the color image data. Is started, and electrostatic latent image formation is started (hereinafter, an electrostatic latent image based on Bk image data is referred to as a Bk electrostatic latent image; the same applies to C, M, and Y). Before the leading edge of the electrostatic latent image reaches the Bk developing position so that the leading edge of the Bk electrostatic latent image can be developed, the Bk developing sleeve 31a starts to rotate, and the Bk electrostatic latent image is transformed with Bk toner. develop. Thereafter, the developing operation of the Bk electrostatic latent image area is continued, but when the rear end portion of the Bk electrostatic latent image passes the Bk developing position, the K developing device 30K is separated from the photosensitive belt 11, The developing device of the corresponding color comes into contact with the photosensitive belt 11 in preparation for the development of the next color. This is completed at least before the leading edge of the electrostatic latent image based on the next image data reaches the developing position.
The intermediate transfer unit 40 includes an intermediate transfer belt 41, a belt cleaning device 42, a position detection sensor 43, and the like. The intermediate transfer belt 41 is stretched around a drive roller 44, a primary transfer roller 45, a secondary transfer counter roller 46, a cleaning counter roller 47, and a tension roller 48, and is driven and controlled by a drive motor (not shown). A plurality of position detection marks are provided in the non-image forming area at the end of the intermediate transfer belt 41, and any one of these position detection marks is detected by the position detection sensor 43, and this detection is performed. Image formation starts at the timing. Further, the belt cleaning device 42 includes a cleaning brush 42a, a contact / separation mechanism, and the like, while transferring the Bk image of the first color to the intermediate transfer belt 41 and the images of the second, third, and fourth colors. During the transfer to the intermediate transfer belt 41, the cleaning brush 42a is separated from the surface of the intermediate transfer belt 41 by the contact / separation mechanism.
Further, the secondary transfer unit 50 includes a contact / separation mechanism including a clutch or the like for contacting / separating the secondary transfer roller 51, the secondary transfer roller 51 to / from the intermediate transfer belt 41. The secondary transfer roller 51 swings about the rotation axis of the contact / separation mechanism in accordance with the timing when the transfer paper reaches the transfer position. The secondary transfer roller 51 and the secondary transfer counter roller 46 bring the transfer paper and the intermediate transfer belt 41 into contact with each other with a constant pressure. The secondary transfer roller 51 has a positional accuracy of parallelism with the secondary transfer counter roller 46 by a positioning member (not shown) provided in the intermediate transfer unit 40. Further, the contact pressure of the secondary transfer roller 51 with respect to the intermediate transfer belt 41 is made constant by a positioning roller (not shown) provided on the secondary transfer roller 51. At the same time as the secondary transfer roller 51 is brought into contact with the intermediate transfer belt 41, a transfer bias having a polarity opposite to that of the toner is applied to the secondary transfer roller 51, and the superimposed toner images on the intermediate transfer belt 41 are collectively transferred onto the transfer paper.

On the other hand, at the time when the image forming operation is started, the transfer paper is fed from either the transfer paper cassette 80 or the manual feed tray 83 and is waiting at the nip of the pair of registration rollers 82. Then, when the leading edge of the four-color superimposed toner image on the intermediate transfer belt 41 approaches the secondary transfer roller 51, the registration roller pair 82 is driven so that the leading edge of the transfer paper coincides with the leading edge of the toner image. The transfer paper and the toner image are aligned. Then, the transfer paper is superimposed on the toner image on the intermediate transfer belt 41 and passes through the secondary transfer position. At this time, the transfer paper is charged by the transfer bias by the secondary transfer roller 51, and most of the toner image is transferred onto the transfer paper. Then, the transfer paper onto which the four-color superimposed toner images are collectively transferred from the intermediate transfer belt 41 is conveyed to the fixing unit 60, and the toner image is melted at the nip portion between the fixing belt 61 and the pressure roller 62 controlled to a predetermined temperature. is fixed, is fed out of the apparatus main body, it is stacked face down in the discharge tray 8 4, obtaining a full-color copy.

Furthermore, when performing duplex printing, the transfer paper that has passed through the fixing unit 60 is sent to the duplex printing paper reversing unit 70 by the duplex switching claw 85. In the double-sided printing paper reversing unit 70, the transfer paper is first guided in the direction of arrow D by the reversal switching claw 71, and after the rear end of the transfer paper passes through the reversal switching claw 71, the reversing roller pair 72 stops and the transfer paper also Stop. Then, the reverse roller pair 72 starts reverse rotation after a certain blank time, and the transfer paper starts to switch back. At this time, the reverse switching claw 71 is switched, and the transfer paper is sent to the registration roller pair 82. The transfer sheet sent to the registration roller pair 82 stands by at the nip of the registration roller pair 82 with the front and back reversed. Then, the registration roller pair 82 is driven at a predetermined timing, the transfer paper is sent to the secondary transfer position, and the four-color superimposed toner image is collectively transferred from the intermediate transfer belt 41, and then the toner image is melted by the fixing unit 60. It is fixed and sent out of the main body.
On the other hand, the surface of the photoconductor belt 11 after the primary transfer can be cleaned by the photoconductor cleaning device 12 and uniformly discharged with a charge removal lamp or the like to facilitate cleaning. Further, the surface of the intermediate transfer belt 41 after the toner image is transferred onto the transfer paper is cleaned by pressing the cleaning brush 42a of the belt cleaning device 42 with a contact / separation mechanism. The toner cleaned from the intermediate transfer belt 41 is stored in a waste toner tank 49.

Here, the developing device will be further described in detail. The developing device 30 includes a developing sleeve 31a that rotates while carrying toner on the surface to develop an electrostatic latent image on the surface of the photoreceptor belt 11, and a toner first conveyance paddle 31d that rotates to pump up and stir the toner. And a toner cartridge 32 for containing toner. The reason why it is divided into two units in this way is that the developing unit 31 has durability that can withstand even if the toner cartridge 32 is replaced several times.
10A and 10B are schematic views showing the configuration of the communication port 33 in the developing device of the present invention. FIG. 10A shows the configuration on the developing unit 31 side, and FIG. 10B shows the configuration on the toner cartridge side. A slide shutter is provided outside the housing of the developing unit 31, and an elastic member is attached to the slide shutter. The communication port 33 of the developing unit 31 is opened and closed by opening and closing this slide shutter. Further, the toner cartridge 32 side is an elastic member having a portion corresponding to the communication port 33 provided in the housing, and is opened so that toner can be prevented from spilling from the communication port 33 or the toner can be replenished. A sliding shutter is provided, and a fixing seal for fixing these to the housing is provided.
By arranging the toner cartridge 32 in the developing device, the slide shutter on the developing unit 31 side is opened, and the slide shutter on the toner cartridge 32 side is opened to form a communication port 33 through which toner can pass.
There are a plurality of communication ports 33 on the developing unit 31 side, and a slide shutter with an elastic member attached is provided between the developing unit 31 and the toner cartridge 32. By moving the slide shutter, the communication port 33 provided in the housing of the developing unit 31 is opened and closed. When there is no toner cartridge 32 or when it is not attached to the image forming apparatus main body, the communication port 33 is closed with a slide shutter to prevent toner from spilling from the developing unit 31.
Further, when the developing unit 31 is not provided or the toner cartridge 32 is not attached to the main body of the image forming apparatus, the communication port 33 is closed in order to prevent the toner from spilling out from the toner cartridge 32. Provide a slide shutter. An elastic member, a slide shutter, and a fixed seal are provided for the toner cartridge 32. The elastic member is preferably a foamed material such as urethane resin or silicone resin.
As shown in FIG. 10, a window portion opened to the slide shutter is provided corresponding to the communication port 33 provided in the developing unit 31 and the toner cartridge 32. When the communication port 33 is closed, the communication port 33 is closed where there is no window portion of the slide shutter, and when the communication port 33 is opened, the slide shutter is moved so that the window portion and the communication port 33 are aligned with each other. To communicate.

In the image forming apparatus 1, the developing device 30 transports the toner to the developer supply roller 31b while stirring the toner with the first transport paddle 31d in the developing unit 31, and the supply roller 31b rubs against the developing sleeve 31a. At the same time, the toner is rubbed and frictionally charged to charge the toner. The charged toner is attracted to the developing sleeve 31a with a mirror image force and conveyed. Thereafter, the amount of toner conveyed to the development area is regulated by the regulation roller 31c. A thin toner layer formed on the developing sleeve 31a is developed on the photosensitive belt with a developing bias in the developing region.
At this time, the toner rubbed against the developing sleeve 31a by the supply roller 31b receives a large pressing force, and the irregularities on the surface of the toner are scraped to become spherical and increase the adhesion force of the toner. Further, the external additive on the surface of the toner is buried by this pressing force and the fluidity is lowered, and further, the charge amount cannot be adjusted by the external additive, so that the charge amount is changed. Under these influences, the developing property of the toner is lowered, and further, the transfer property and the cleaning property are lowered.
Thus, the amount of deteriorated toner increases in the developing hopper, and the toner in the developing unit 31 decreases because the toner is consumed by development. Therefore, the toner is supplied from the toner cartridge 32 to the developing unit 31 through the communication port 33. In the toner cartridge 32, a second transport paddle 32a and a third transport paddle 32b whose tips are in sliding contact with the inner wall of the toner cartridge main body 32 are provided in the first storage chamber 321 and the second storage chamber 322, respectively. Alternatively, the third transport paddles 32 a and 32 b rotate to push the toner into the developing unit 31, and the toner is supplied to the developing unit 31 from the communication port 33.

Further, the toner in the developing unit 31 is discharged to the toner cartridge 32 through the communication port 33, and the toner is mixed with the toner in the toner cartridge 32. A large amount of unused toner is stored in the toner cartridge 32 and is mixed with the deteriorated toner in the developing unit 31. As a result of this mixing, the external additive present in large amounts on the surface of the unused toner is redistributed to the deteriorated toner, whereby the charge amount and fluidity of the deteriorated toner become close to those of the original unused toner. This is because the toner discharged from the developing unit 31 to the first storage chamber 321 is further transported to the second storage chamber 322 by the second transport paddle, and then to the first storage chamber 321 by the third transport paddle. Returned. During this time, the external additive is redistributed.
The toner approaching the original unused state is supplied again from the first storage chamber 321 of the toner cartridge 32 to the developing unit 31. A high-quality image can be obtained over a long period of time by forming a thin layer on the developing sleeve 31a and developing the toner with the toner that has approached the original state and the unused toner.

  Further, the developing device 30 can be a process cartridge that is integrally supported together with the photosensitive member 10 and is detachably formed on the image forming apparatus main body. In addition, the process cartridge may include a charging unit and a cleaning unit.

  The toner of the present invention contains at least a binder resin, a colorant, and a charge control agent. The toner production method of the present invention will be described in detail below.

(Polyester resin)
As the binder resin, a polyester resin suitable as a binder resin for full-color toner is used from the viewpoint of color development and image strength. In a color image, several kinds of toner layers are stacked several times, so that the toner layer becomes thick, and cracks and defects of the image due to insufficient strength of the toner layer occur, or an appropriate gloss is lost. For this reason, a polyester resin is used to maintain an appropriate gloss and excellent strength.

  The polyester resin can be generally obtained by an esterification reaction of a polyhydric alcohol and a polycarboxylic acid. Among the monomers constituting the polyester resin in the present invention, as the alcohol monomer, as the diol monomer, for example, ethylene glycol, diethylene glycol triethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4 Diols such as butadiene ol, neopentyl glycol, 1,4-butenediol, 1,5-pentanediol, 1,6-hexanediol, bisphenols such as bisphenol A, hydrogenated bisphenol A, polyoxypropylenated bisphenol A, etc. Examples include A alkylene oxide adducts and other dihydric alcohols such as sorbitol, 1,2,3,6-hexanetetrol, 1,4-sorbitan, pentaerythritol, dipentaerythritol. Tripentaerythritol, 1,2,4-butanetriol, 1,2,5-pentanetriol, glycerol, diglycerol, 2-methylpropanetriol, 2-methyl-1,2,4-butanetriol, trimethylolethane, Examples thereof include trimethylolpropane, 1,3,5-trihydroxybenzene, oxyalkylene ether of a novolac type phenol resin, and other trihydric or higher polyhydric alcohols. Trihydric or higher alcohol monomers are mainly used as a crosslinking component. Among these monomers, those using a bisphenol A alkylene oxide adduct as a main component monomer are preferably used. When a bisphenol A alkylene oxide adduct is used as a constituent monomer, a polyester having a relatively high glass transition point is obtained due to the nature of the bisphenol A skeleton, and the copy blocking resistance and heat resistant storage stability are good. In addition, the presence of alkyl groups on both sides of the bisphenol A skeleton acts as a soft segment in the polymer, and the color developability and image strength during toner fixing are improved. Of the bisphenol A alkylene oxide adducts, those having an ethylene group or a propylene group are preferably used.

  Among the monomers constituting the polyester resin in the present invention, examples of the acid monomer include maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, phthalic acid, isophthalic acid, terephthalic acid, cyclohexanedicarboxylic acid, succinic acid, Adipic acid, sebacic acid, azelaic acid, malonic acid, alkenyl succinic acids such as n-dodecenyl succinic acid or alkyl succinic acids such as n-dodecyl succinic acid, anhydrides of these acids, alkyl esters, other divalent carboxylic acids And 1,2,4-benzenetricarboxylic acid, 2,5,7-naphthalenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, 1,2,4- Butanetricarboxylic acid, 1,2,5-hexanetricarboxylic acid, 1 3-dicarboxyl-2-methyl-methylenecarboxypropane, tetra (methylenecarboxyl) methane, 1,2,7,8-octanetetracarboxylic acid, empole trimer acid, and anhydrides thereof, alkyl esters, alkenyl esters , Aryl esters, and other trivalent or higher carboxylic acids. Specific examples of the tricarboxylic acid and its alkyl, alkenyl or aryl ester described herein include 1,2,4-benzenetricarboxylic acid, trimethyl 1,2,4-benzenetricarboxylate, 1,2,4-benzenetricarboxylic acid. Triethyl acid, tri-n-butyl 1,2,4-benzenetricarboxylate, triisobutyl 1,2,4-benzenetricarboxylate, tri-n-octyl 1,2,4-benzenetricarboxylate, 1,2,4-benzene Examples include tri-2-ethylhexyl tricarboxylate, tribenzyl 1,2,4-benzenetricarboxylate, tris (1,4-benzylbenzyl) 1,2,4-benzenetricarboxylate, and the like.

  In particular, the polyester resin of the present invention has no THF-insoluble matter, and the content of components having a molecular weight of 500 or less is 4% by weight or less, preferably 1 to 4% by weight in the molecular weight distribution in gel permeation chromatography (GPC). It preferably has one peak in the molecular weight region of 3000 to 9000. When THF-insoluble matter enters, the glossiness is lowered and the transparency is lowered, and a high-quality image cannot be obtained when an OHP sheet is used. Further, when the component having a molecular weight of 500 or less is 4% by weight, a brittle component as a resin can be reduced, and so-called filming component to be fused and fine particle formation in a developing machine can be suppressed. As a result, the non-magnetic one-component development system can withstand long-term use, and can be used in the toner replenishment system. From the viewpoint of ease of production, the proportion of components having a molecular weight of 500 or less is preferably 1% by weight or more.

The molecular weight distribution of the present invention is measured by GPC as follows. A toner base THF sample prepared by stabilizing the column in a heat chamber at 40 ° C., and flowing THF as a solvent at a flow rate of 1 mL / min and adjusting the sample concentration to 0.05 to 0.6% by weight. 200 μL of the solution is injected and measured. Prior to injection, the THF sample solution is removed with a 0.45 μm liquid chromatography filter to remove THF-insoluble components. In measuring the molecular weight of the toner sample, the molecular weight distribution of the sample was calculated from the relationship between the logarithmic value of a calibration curve prepared from several monodisperse polystyrene standard samples and the number of counts. As a standard polystyrene sample for preparing a calibration curve, for example, Pressure Chemical Co. Alternatively, the molecular weights of Toyo Soda Kogyo Co., Ltd. are 6 × 10 ² , 2.1 × 10 ³ , 4 × 10 ³ , 1.75 × 10 ⁴ , 5.1 × 10 ⁴ , 1.1 × 10 ⁵ , 3. It is appropriate to use 9 × 10 ⁵ , 8.6 × 10 ⁵ , 2 × 10 ⁶ , 4.48 × 10 ⁶ , and use at least about 10 standard polystyrene samples. An RI (refractive index) detector is used as the detector. Whether or not the binder resin is insoluble in THF is determined at the time of preparing a THF sample solution for molecular weight distribution measurement. That is, when a 0.45 μm filter unit is attached to the tip of the syringe and the liquid is pushed out from the syringe, it is determined that there is no THF-insoluble matter unless the filter is clogged.

  Moreover, it is preferable that the glass transition point (Tg) of a polyester resin is the range of 55-70 degreeC. The glass transition point was measured using a TG-DSC system TAS-100 manufactured by Rigaku Corporation. In the measurement, first, a sample is placed in an aluminum sample container of about 10 mg, placed on a holder unit, and set in an electric furnace. First, after heating from room temperature to 150 ° C. at a rate of temperature increase of 10 ° C./min, the sample was allowed to stand at 150 ° C. for 10 min, the sample was cooled to room temperature and left for 10 min, and the rate of temperature increase to 150 ° C. again under a nitrogen atmosphere was 10 ° C./min. DSC measurement was performed by heating at Tg was calculated from the contact point between the endothermic curve near the Tg and the baseline using the analysis system in the TAS-100 system.

(Charge control agent)
As the charge control agent, a positive or negative charge control agent may be used as appropriate depending on whether the charge charged on the photoconductor is positive or negative. As the negative charge control agent, for example, a resin or compound having an electron donating functional group, an azo dye, or a metal complex of an organic acid can be used. Specifically, Bontron (product numbers: S-31, S-32, S-34, S-36, S-37, S-39, S-40, S-44, E-81, E-82, E -84, E-86, E-88, A, 1-A, 2-A, 3-A) (above, manufactured by Orient Chemical Industry Co., Ltd.)}, Kaya charge (product numbers: N-1, N-2), Kaya Set Black (Part No .: T-2, 004) (above, Nippon Kayaku Co., Ltd.)}, Eisenspiron Black (T-37, T-77, T-95, TRH, TNS-2) FCA-1001-N, FCA-1001-NB, FCA-1001-NZ, (manufactured by Fujikura Kasei Co., Ltd.)} and the like can be used. As the positive charge control agent, for example, a basic compound such as a nigrosine dye, a cationic compound such as a quaternary ammonium salt, a metal salt of a higher fatty acid, or the like can be used. Specifically, Bontron (part numbers: N-01, N-02, N-03, N-04, N-05, N-07, N-09, N-10, N-11, N-13, P -51, P-52, AFP-B) (above, manufactured by Orient Chemical Co., Ltd.), TP-302, TP-415, TP-4040 (above, manufactured by Hodogaya Chemical Co., Ltd.), Copy Blue PR, Copy Charge ( Product number: PX-VP-435, NX-VP-434) (manufactured by Hoechst), FCA (product number: 201, 201-B-1, 201-B-2, 201-B-3, 201-PB, 201-PZ, 301) (manufactured by Fujikura Kasei Co., Ltd.), PLZ (product numbers: 1001, 2001, 6001, 7001) (manufactured by Shikoku Kasei Kogyo Co., Ltd.) and the like can be used.

  In particular, it is preferable to use a salicylic acid metal salt from the viewpoint that the charge rising property of the toner replenished by the replenishment mechanism is fast and the charge amount distribution is sharp even in a usage environment where stress on the toner is applied over a long period of time. . Further, the addition amount of the charge control agent is preferably 0.5 to 5.0% by weight, more preferably 1.5 to 3.0% by weight with respect to the toner particles. If it is less than 0.5% by weight, it is difficult to keep the charge particularly in a long period in the one-component development method. When the amount is more than 5.0% by weight, the dispersibility of the charge control agent in the resin tends to be deteriorated, and quality deterioration such as background stains is caused in long-term use.

(External additive)
A method of mixing toner particles and inorganic powders such as various metal oxides for the purpose of improving the flow characteristics and charging characteristics of the toner has been proposed and is called an additive. If necessary, the surface of the inorganic powder may be treated with a specific silane coupling agent, titanate coupling agent, silicone oil, organic acid, etc., or a specific resin may be coated to improve the hydrophobicity or charging characteristics of the surface of the inorganic powder. A method to do this has also been proposed. As the inorganic powder, for example, silicon dioxide (silica), titanium dioxide (titania), aluminum oxide, zinc oxide, magnesium oxide, cerium oxide, iron oxide, copper oxide, tin oxide and the like are known. In particular, silica particles obtained by reacting silica or titanium oxide fine particles with an organosilicon compound such as dimethyldichlorosilane, hexamethyldisilazane, or silicone oil to replace the silanol groups on the surface of the silica fine particles with organic groups to make them hydrophobic are used.

It is preferable that 1.3 to 3.2 parts by weight of the above-described inorganic fine particles as external additives are added to the toner surface with respect to 100 parts by weight of the toner base.
Among these, it is preferable to contain two or more kinds of external additives having different particle diameters, and it is preferable to contain an external additive having a particle diameter difference of about 2 to 5 times in average particle diameter. When two or more types of external additives having different particle diameters are not contained, the external additive is rapidly embedded in the toner base material over time, and toner fluidity is rapidly deteriorated. Image unevenness due to a decrease in toner fluidity is likely to occur, and the adhesion to the toner is difficult to increase, so that the toner is easily detached from the toner, causing a photosensitive material scratch and an image blur. If two or more types of external additives with different particle sizes are contained, the large particle size external additive acts as a spacer, preventing the embedding of the small particle size external additive effective in toner fluidity in the toner base Thus, toner fluidity can be maintained. Moreover, although the cause is unknown, the thin layer of the developing carrier over time becomes uniform.

For example, the external additive having a large particle size preferably has a BET specific surface area in the range of 30 to 80 m ² / g, and if the BET specific surface area is in this range, various surface-treated ones are used. In particular, those of 40 to 60 m ² / g are more preferable. If it is less than 30 m ² / g, unevenness in the image due to a sharp drop in the fluidity of the toner is likely to occur, the adhesion to the toner is difficult to increase, and detachment from the toner occurs easily. It may cause scratches and missing images. These external additives having a large particle diameter are preferably added in the range of 0.1 to 3.0 parts by weight, and in the range of 0.8 to 2.0 parts by weight, based on 100 parts by weight of the toner base. Is more preferable. When the amount is less than 0.1 parts by weight, transfer failure occurs. When the amount exceeds 3.0 parts by weight, detachment from the toner easily occurs, which may cause damage to the photosensitive material and image loss.

The external additive having a small particle size preferably has a BET specific surface area in the range of 100 to 250 m ² / g, and if the BET specific surface area is in this range, various surface-treated ones can be used. In particular, those of 120 to 200 m ² / g are more preferable. In particular, it is effective for reducing the adhesion force of the toner. These external additives are preferably added in the range of 0.1 to 3 parts by weight, more preferably in the range of 0.5 to 1.5 parts by weight, based on 100 parts by weight of the toner base. When the amount is less than 0.1 part by weight, the effect is not sufficiently exerted, and when the amount exceeds 3 parts by weight, the amount of the external additive that is detached from the toner increases, and the photosensitive member is likely to be damaged.

(Coloring agent)
Further, other constituent materials of the toner of the present invention are shown below.
As the colorant used in the present invention, all known dyes and pigments can be used. For example, carbon black, nigrosine dye, iron black, etc. can be used as the black colorant used for the black toner. Examples of the yellow colorant used for the yellow toner include naphthol yellow S, Hansa yellow (10G, 5G, G), cadmium yellow, yellow iron oxide, ocher, yellow lead, titanium yellow, polyazo yellow, oil yellow, and 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, Iso Indolinone yellow can be used.

Examples of red colorants used for magenta toner include Bengala, Red Dan, Lead Zhu, Cadmium Red, Cadmium Mercury Red, Antimon Zhu, Permanent Red 4R, Para Red, Faise Red, Parachlor Ortho Nitroaniline 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, Pogment Scarlet 3B, Bordeaux 5B, Tolujing Maroon, Permanent Bordeaux F2K, Helio Bordeaux BL, Bordeaux 10B, Bonmaru Nlite, Bonmaroon Medium, Eosin Lake, Rhodamine Lake B, Rhodamine Lake Y, Alizarin Lake, Thioindigo Red B, Thioindigo Maroon, Oil Red, Quinacridone Red, Pyrazolone Red, Polyazo Red, Chrome Vermilion, Benzidine Orange, Perinone Orange, oil orange, etc. can be used.
Blue colorants used for cyan toners include cobalt blue, cerulean blue, alkali blue rake, peacock blue rake, Victoria blue rake, 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, Phthalocyanine Green, Anthraquinone Green, etc. That. As other colorants, titanium oxide, zinc white, ritbon and mixtures thereof can be used. The amount used is generally 0.1 to 50% by weight with respect to 100% by weight of the binder resin.

  In particular, the colorant is pre-treated with the binder resin to increase the dispersibility of the pigment in the binder resin, to obtain a sufficient coloring power with the content, to improve the transparency and color developability of the toner, and to control charging. It can be done easily. The pretreatment with the resin is one in which a binder resin and a colorant are melt-kneaded at a certain ratio and coarsely pulverized. In general, the mixing ratio is desirably 1 to 5% by weight of the resin with respect to 1% by weight of the colorant. If the colorant is less than 1% by weight relative to 1% by weight of the resin, the colorant cannot be sufficiently dispersed. On the other hand, if the amount exceeds 1% by weight of the colorant and more than 5% by weight of the resin, the dispersing power does not act on the colorant, and sufficient dispersion cannot be achieved. When two or more kinds of colorants are used, they may be processed individually, or may be processed after mixing pigments in advance.

(wax)
Wax may be included in the toner in order to give the manufactured toner releasability. The wax has a melting point of 40 to 120 ° C., and preferably 50 to 110 ° C. When the melting point of the wax is excessive, the fixing property at a low temperature may be insufficient. On the other hand, when the melting point is excessively low, the offset resistance and durability may be decreased. The melting point of the wax can be obtained by differential scanning calorimetry (DSC). That is, the melting peak value when a sample of several mg is ripened at a constant temperature increase rate, for example, (10 ° C./min) is defined as the melting point.

  Examples of the wax that can be used in the present invention include solid paraffin wax, micro wax, rice wax, fatty acid amide wax, fatty acid wax, aliphatic monoketone, fatty acid metal salt wax, fatty acid ester wax, and partial kenne. And fatty acid ester wax, silicone varnish, higher alcohol, carnauba wax and the like. Also, polyolefins such as low molecular weight polyethylene and polypropylene can be used. Particularly, a polyolefin having a softening point of 70 to 150 ° C. by the ring and ball method is preferable, and a polyolefin having a softening point of 120 to 150 ° C. is more preferable.

  Examples of the cleaning performance improver for removing the developer after transfer remaining on the latent image carrier 11 or the primary transfer medium 41 include fatty acid metal salts such as zinc stearate, calcium stearate, stearic acid, and polymethyl methacrylate fine particles. And polymer fine particles produced by soap-free emulsion polymerization such as polystyrene fine particles. The polymer fine particles preferably have a relatively narrow particle size distribution and a volume average particle size of 0.01 to 1 μm.

(Crushing method)
The toner production method of the present invention may be any conventionally known method. The step of mechanically mixing toner raw materials including at least a binder resin, a colorant, and a charge control agent, a step of melt kneading, and the obtained kneading A toner production method having a step of cooling and pulverizing a product and a step of classifying the product can be applied. In addition, in the mechanical mixing step and the melt kneading step, a production method is also included in which the powder other than the particles obtained as a product obtained in the pulverization or classification step is returned and reused.
The powders (sub-products) other than the particles used as the product referred to here are fine particles and coarse particles other than the components used as the product having a desired particle size obtained in the pulverization step after the melt-kneading step, and a subsequent classification step. It means fine particles or coarse particles other than the components that are generated as products having a desired particle diameter. It is preferable to mix 1 to 20% by weight of the by-product with the raw material and preferably the main raw material 100 in the step of mixing or melt-kneading such a by-product.

When the above mixing process is completed, the mixture is then charged into a kneader and melt-kneaded. As the melt kneader, a uniaxial or biaxial continuous kneader or a batch kneader using a roll mill can be used. For example, KTK type twin screw extruder manufactured by Kobe Steel, TEM type extruder manufactured by Toshiba Machine Co., Ltd., twin screw extruder manufactured by Kay Sea Kay Co., Ltd., PCM type twin screw extruder manufactured by Ikegai Iron Works Co., Ltd. A kneader or the like is preferably used. It is important that this melt-kneading is performed under appropriate conditions that do not cause the molecular chains of the binder resin to be broken. Specifically, the melt-kneading temperature should be performed with reference to the softening point of the binder resin. If the temperature is higher than the softening point, cutting is severe, and if the temperature is too low, dispersion does not proceed.

When the above melt-kneading process is completed, the kneaded product is then pulverized. In this pulverization step, it is preferable to first coarsely pulverize and then finely pulverize. At this time, a method of pulverizing by colliding with a collision plate in a jet stream, pulverizing particles by colliding with each other in a jet stream, or pulverizing with a narrow gap between a mechanically rotating rotor and a stator is preferably used.
After the pulverization step is completed, the pulverized product is classified in an air stream by centrifugal force or the like, thereby producing a toner having a predetermined particle size, for example, an average particle size of 5 to 20 μm.

  In addition, when preparing the toner, in order to improve the fluidity, storage stability, developability, and transferability of the toner, the hydrophobic silica fine powder listed above is further added to the toner manufactured as described above. Inorganic fine particles may be added and mixed. For mixing the additives, a general powder mixer is used, but it is preferable to equip a jacket or the like to adjust the internal temperature. In order to change the load history applied to the additive, the additive may be added in the middle or gradually. Of course, you may change the rotation speed of a mixer, rolling speed, time, temperature, etc. A strong load may be given first, then a relatively weak load, and vice versa. Examples of the mixing equipment that can be used include a V-type mixer, a rocking mixer, a Ladige mixer, a Nauter mixer, a Henschel mixer, and the like. Next, it is passed through a sieve of 250 mesh or more to remove coarse particles and aggregated particles, and the toner of the present invention is obtained.

  In the developing device according to the present invention, the toner manufactured as described above is mainly used as a one-component non-magnetic toner that does not use a magnetic carrier. In addition, the toner contains a magnetic component. It can also be used as a one-component magnetic toner.

The toner used in the image forming apparatus of the present invention may be a toner manufactured by a polymerization method in addition to the toner manufactured by the pulverization method as described above.
Among these toners produced by the polymerization method, a toner in which at least a polymer having a site capable of reacting with a compound having an active hydrogen group, a polyester, a colorant, and a release agent are dissolved or dispersed in an organic solvent. The material liquid is obtained by crosslinking and / or elongation reaction in an aqueous medium. Hereinafter, 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.
In addition, as a dihydric alcohol (DIO) and a trihydric or more polyhydric alcohol (TO), the thing similar to what was used by the said grinding | pulverization method can be used.

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.
In addition, as divalent carboxylic acid (DIC) and trivalent or higher polyvalent carboxylic acid (TC), the same ones as used in the above pulverization method can be used.
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.

  In addition to the polyhydric alcohol compound (PO) and polyhydric carboxylic acid (PC) used in the above pulverization method, other polyhydric alcohol compounds (PC) may be used as long as they can form a polyester having an active hydrogen group by polycondensation. It is also possible to use things.

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).

(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 the single use. Examples of (ii) include polycondensates of a polyhydric alcohol (PO) and a polyvalent carboxylic acid (PC), which are the same as the polyester component (i), and preferred ones are also the same as (i). . Further, (ii) is not limited to unmodified polyester, but may be modified with a chemical bond other than a urea bond, for example, may be modified with a urethane bond. It is preferable that (i) and (ii) are at least partially compatible with each other in terms of low-temperature fixability and hot offset resistance. Therefore, the polyester component (i) and (ii) preferably have similar compositions. In the case of containing (ii), 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. If the weight ratio of (i) is less than 5%, the hot offset resistance deteriorates, and it is disadvantageous in terms of both heat-resistant storage stability and low-temperature fixability.

  The peak molecular weight of (ii) is 1000-10000 normally, Preferably it is 2000-8000, More preferably, it is 2000-5000. 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. As for the acid value of (ii), 1-5 are preferable, More preferably, it is 2-4. 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 the temperature is lower than 35 ° C., the heat-resistant storage stability of the toner deteriorates, and if it exceeds 70 ° C., the low-temperature fixability becomes 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.

  Furthermore, the same charge control agent, mold release agent and colorant as those used in the pulverization method can be used.

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 0-300 weight part normally with respect to 100 weight part of polyester prepolymers, Preferably it is 0-100 weight part, More preferably, it is 25-70 weight part.

2) The toner material liquid is emulsified in an aqueous medium in the presence of a surfactant and resin fine particles.
The aqueous medium may be water alone or an organic solvent such as alcohol (methanol, isopropyl alcohol, ethylene glycol, etc.), dimethylformamide, tetrahydrofuran, cellosolves (methyl cellosolve, etc.), lower ketones (acetone, methyl ethyl ketone, etc.). It may be included.
The amount of the aqueous medium used relative to 100 parts by weight of the toner material liquid is usually 50 to 2000 parts by weight, preferably 100 to 1000 parts by weight. If the amount is less than 50 parts by weight, the dispersion state of the toner material liquid is poor, and toner particles having a predetermined particle diameter cannot be obtained. If it exceeds 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).

As the cationic surfactants, aliphatic primary to have a fluoroalkyl group, 2 primary or secondary amine acids, aliphatic quaternary ammonium, such as perfluoroalkyl (C6 ~ C10) sulfonamide propyl trimethyl ammonium salt 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.

As the resin fine particles, any resin can be used as long as it can form an aqueous dispersion, and it may be a thermoplastic resin or a thermosetting resin. Examples thereof include vinyl resins, polyurethane resins, epoxy resins, polyester resins, polyamide resins, polyimide resins, silicon resins, phenol resins, melamine resins, urea resins, aniline resins, ionomer resins, and polycarbonate resins. As the resin, two or more of the above resins may be used in combination.
Of these, vinyl resins, polyurethane resins, epoxy resins, polyester resins, and combinations thereof are preferred because an aqueous dispersion of fine spherical resin particles is easily obtained. For example, vinyl resins are polymers obtained by homopolymerization or copolymerization of vinyl monomers, such as styrene- (meth) acrylic acid ester copolymers, styrene-butadiene copolymers, (meth) acrylic acid-acrylic acid esters. Examples thereof include resins such as a polymer, a styrene-acrylonitrile copolymer, a styrene-maleic anhydride copolymer, and a styrene- (meth) acrylic acid copolymer. The average particle size of the resin fine particles is 5 to 200 nm, preferably 20 to 300 nm. 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 number of rotations is not particularly limited, but is usually 1000 to 30000 rpm, preferably 5000 to 20000 rpm. The dispersion time is not particularly limited, but in the case of a batch method, it is usually 0.1 to 5 minutes. The temperature during dispersion is usually 0 to 150 ° C. (under pressure), preferably 40 to 98 ° C.

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

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

5) A charge control agent is injected into the toner base particles obtained above, and then inorganic fine particles such as silica fine particles and titanium oxide fine particles are externally added to obtain a toner.
The injection of the charge control agent and the external addition of the inorganic fine particles are performed by a known method using a mixer or the like.
Thereby, a toner having a small particle size and a sharp particle size distribution can be easily obtained. Furthermore, by giving strong agitation in the process of removing the organic solvent, the shape between the true spherical shape and the rugby ball shape can be controlled, and the surface morphology is also controlled between the smooth shape and the umeboshi shape. be able to.

In the developing device according to the present invention, the toner produced as described above is mainly used as a one-component non-magnetic toner that does not use a magnetic carrier, but besides this, a magnetic component is contained in the toner, It can also be used as a one-component magnetic toner.
The toner obtained by the above production method is preferably used as a color toner. It is excellent in reproducibility of fine lines and fine dots, is excellent in toner granularity, and is excellent in reproducibility of intermediate colors, so that it is more suitable for use as a color toner for forming a color image.

  Hereinafter, the present invention will be described, but the present invention is not limited to the following examples. First, the form of the toner cartridge used in Examples and Comparative Examples is shown.

(Cartridge C1)
[Cartridge C1] includes a transport paddle (rotary body) 32a for stirring / moving the toner, and a rib 35 (plate-shaped) that contacts the transport paddle (rotary body) 32a and promotes the return of the toner into the cartridge 32. Member) was provided on the inner wall of the cartridge 32. FIG. 11 shows a cross-sectional view of [Cartridge C1].

(Cartridge C2)
[Cartridge C2] was provided only with a transport paddle (rotating body) 32a for stirring / moving the toner. FIG. 12 shows a cross-sectional view of [Cartridge C2].

(Synthesis Example 1)
~ Synthesis of polyester resin a ~
In a 4-neck separable flask with a stirrer, thermometer, nitrogen inlet, flow-down condenser, and condenser, 740 g of polyoxypropylene (2,2) -2,2-bis (4-hydroxyphenyl) propane, polyoxy Esterification catalyst of 300 g of ethylene (2,2) -2,2-bis (4-hydroxyphenyl) propane, 466 g of dimethyl terephthalate, 80 g of isododecenyl succinic anhydride, and 114 g of tri-n-butyl 1,2,4-benzenetricarboxylate Added with.
Subsequently, it was made to react at 210 degreeC under nitrogen atmosphere for 8 hours, and then it was made to react for 5 hours, stirring at 210 degreeC pressure reduction. Thereby, [polyester resin a] having a glass transition temperature (Tg) of 62 ° C. and an Mw / Mn ratio of 5.1 was synthesized.

(Synthesis Example 2)
~ Synthesis of polyester resin b ~
In Synthesis Example 1, 650 g of polyoxypropylene (2,2) -2,2-bis (4-hydroxyphenyl) propane, 650 g of polyoxyethylene (2,2) -2,2-bis (4-hydroxyphenyl) propane , Except that 515 g of isophthalic acid, 70 g of isooctenyl succinic acid, and 80 g of 1,2,4-benzenetricarboxylic acid were added to the flask together with the esterification catalyst, the reaction was performed in the same apparatus and the same formulation as in Synthesis Example 1. [Polyester resin b] was synthesized by shortening the reaction time.
[Polyester resin b] obtained had a glass transition temperature (Tg) of 61 ° C. and an Mw / Mn ratio of 2.7.

(Synthesis Example 3)
~ Synthesis of polyester resin c ~
[Polyester resin c] was synthesized by the same method as in Synthesis Example 1 with the same formulation as in Synthesis Example 2.
The obtained [Polyester resin c] had a glass transition temperature (Tg) of 67 ° C. and an Mw / Mn ratio of 4.6.

(Production Example 1)
-Preparation of base toner A-
Raw material composition binder resin: polyester resin a: 100% by mass
Colorant: Carbon black: 5% by mass
Charge control agent: Bontron E-84 (manufactured by Orient Chemical Co., Ltd.) 2% by mass
The toner material was mixed using a Henschel mixer (manufactured by Mitsui Miike Co., Ltd.), and then kneaded for 30 minutes with two rolls having a roll surface set at 100 ° C. Thereafter, after rolling and cooling and coarse pulverization, a jet mill type pulverizer (I-2 type mill: manufactured by Nippon Pneumatic Kogyo Co., Ltd.) and a wind classifier using a swirling flow (DS classifier: manufactured by Nihon Pneumatic Kogyo Co., Ltd.) A black [base toner A] having a weight average particle diameter of 7.0 μm was obtained.

-Production of Toner T1-
[Base toner A] To 100% by mass, 1.8% by mass of hydrophobic silica H2000 (BET specific surface area 120 m ² / g, manufactured by Clariant Japan) as an additive, and RX-50 (BET specific surface area, manufactured by Nippon Aerosil Co., Ltd.) [Toner T1] was prepared by adding 1.2% by mass of 50 m ² / g) and mixing with a Henschel mixer. [Toner T1] had a weight average particle diameter of 7.0 μm, a powder wall disintegration angle of 50 °, an aggregation degree of 12%, and a loose apparent density of 0.42 g / cm ³ .

(Production Example 2 to Production Example 4)
~ Preparation of base toner B ~ base toner D ~
In Manufacturing Example 1, [Mother toner B] to [Mother toner D] were prepared in the same manner as in Manufacturing Example 1, except that the types and amounts of the binder resin and the charge control agent shown in Table 1 were used. did. The following were used as the charge control agent.
Charge control agent: Bontron E-84 (manufactured by Orient Chemical Industries)
Charge control agent: Bontron X-11 (manufactured by Orient Chemical Industries)

-Production of Toner T2-Toner T8-
In Production Example 1, [Toner T2] to [Toner T8] were produced in the same manner as in Production Example 1, except that the base toner and additives shown in Table 2 were used. Table 2 also shows the weight average particle diameter, powder wall disintegration angle, degree of aggregation, and loose apparent density of [Toner T2] to [Toner T8].
In addition, the following were used as an additive.
Silica (H-2000, Clariant Japan BET specific surface area 120 m ² / g)
Silica (H-3004, manufactured by Clariant Japan, BET specific surface area 200 m ² / g)
Silica (RX-50, manufactured by Nippon Aerosil Co., Ltd., BET specific surface area of 50 m ² / g)

  The electrostatic image developing toner (developer) used in the present invention is not limited to the pulverized toner, and a polymerized toner may be used. Hereinafter, production examples of the polymerized toner will be described.

(Production Example 5)
-Production of inorganic fine particles
Blowing liquid SiCl ₄ ingredients core at a flow rate of Ar gas as a carrier gas using a liquid material supply system 300 SCCM (min standard volume flow (CC)), the SiCl ₄ vapor flow rate 250 SCCM, _{H 2} gas 20 SLM (per Minute standard volume flow rate (L)) and O ₂ gas 20SLM were sent to a core burner for flame hydrolysis and fusion to produce SiO ₂ fine particles. The fine particles were grown to a predetermined primary particle size, and the obtained fine particles were hydrophobized with hexamethyldisilazane to obtain [Inorganic fine particles 1] having an average primary particle size of 5 nm.

(Production Example 6)
~ Synthesis of organic fine particle emulsion ~
In a reaction vessel equipped with a stir bar and a thermometer, 683 parts of water, 11 parts of sodium salt of ethylene oxide methacrylate adduct sulfate (Eleminol RS-30, manufactured by Sanyo Chemical Industries), 80 parts of styrene, 83 parts of methacrylic acid, When 110 parts of butyl acrylate, 12 parts of butyl thioglycolate and 1 part of ammonium persulfate were added and stirred for 15 minutes at 400 rpm, a white emulsion was obtained. The system was heated to raise the system temperature to 75 ° C. and reacted for 5 hours. Further, 30 parts of a 1% ammonium persulfate aqueous solution was added, and the mixture was aged at 75 ° C. for 5 hours, and an aqueous vinyl resin (a copolymer of styrene-methacrylic acid-butyl acrylate-methacrylic acid ethylene oxide adduct sulfate sodium salt). A dispersion was obtained. This is designated as [fine particle dispersion 1]. The volume average particle size of the [fine particle dispersion 1] measured by a laser diffraction particle size distribution analyzer (LA-920, manufactured by Shimadzu Corp.) was 120 nm. A portion of [Fine Particle Dispersion 1] was dried to isolate the resin component. The Tg of the resin was 42 ° C., and the weight average molecular weight was 30,000.

(Production Example 7)
~ Preparation of aqueous phase ~
990 parts of water, 65 parts of [fine particle dispersion 1], 37 parts of 48.5% aqueous solution of sodium dodecyl diphenyl ether disulfonate (ELEMINOL MON-7 manufactured by Sanyo Chemical Industries) and 90 parts of ethyl acetate were mixed and stirred to give a milky white color Obtained liquid. This is designated as [Aqueous Phase 1].

(Production Example 8)
~ Synthesis of low molecular weight polyester ~
In a reaction vessel equipped with a condenser, a stirrer and a nitrogen inlet tube, 229 parts of bisphenol A ethylene oxide 2-mole adduct, 529 parts of bisphenol A propylene oxide 3-mole adduct, 208 parts terephthalic acid, 46 parts adipic acid and dibutyl Add 2 parts of tin oxide, react at 230 ° C for 8 hours at normal pressure, and further react for 5 hours at 10-15 mmHg reduced pressure, then add 44 parts of trimellitic anhydride to the reaction vessel at 180 ° C at normal pressure. The mixture was reacted for 2 hours to obtain [Low molecular weight polyester 1]. [Low molecular polyester 1] had a number average molecular weight of 2500, a weight average molecular weight of 6700, a Tg of 43 ° C., and an acid value of 25.

(Production Example 9)
~ Synthesis of intermediate polyester ~
In a reaction vessel equipped with a cooling pipe, a stirrer and a nitrogen introduction pipe, 682 parts of bisphenol A ethylene oxide 2-mole adduct, 81 parts of bisphenol A propylene oxide 2-mole adduct, 283 parts of terephthalic acid, trimellitic anhydride 22 And 2 parts of dibutyltin oxide were added, reacted at 230 ° C. for 8 hours at normal pressure, and further reacted for 5 hours at a reduced pressure of 10 to 15 mmHg to obtain [Intermediate Polyester 1]. [Intermediate Polyester 1] had a number average molecular weight of 2,100, a weight average molecular weight of 9,500, Tg of 55 ° C., an acid value of 0.5, and a hydroxyl value of 51.

(Production Example 10)
-Synthesis of a modified polyester resin (referred to as prepolymer 1) capable of reacting with a compound having at least an active hydrogen group-
In a reaction vessel equipped with a cooling tube, a stirrer and a nitrogen introduction tube, 410 parts of the above [intermediate polyester 1], 125 parts of isophorone diisocyanate, and 500 parts of ethyl acetate were added and reacted at 100 ° C. for 5 hours. ] Was obtained. The average number of isocyanate groups contained per molecule of [Prepolymer 1] was 2.15.

(Production Example 11)
~ Synthesis of ketimine ~
In a reaction vessel equipped with a stir bar and a thermometer, 170 parts of isophoronediamine and 75 parts of methyl ethyl ketone were charged and reacted at 50 ° C. for 5 hours to obtain [ketimine compound 1]. The amine value of [ketimine compound 1] was 418.

(Production Example 12)
~ Master batch synthesis ~
1200 parts of water, 40 parts of carbon black (Cabot, Regal 400R), 60 parts of polyester resin (manufactured by Sanyo Kasei, RS801), 30 parts of water are added, and they are mixed with a Henschel mixer (manufactured by Mitsui Mining). The mixture was kneaded at 150 ° C. for 30 minutes using two rolls, rolled and cooled, and pulverized with a pulverizer to obtain [Masterbatch 1].

(Production Example 13)
-Production of toner composition containing oil phase, that is, inorganic fine particles-
In a container equipped with a stir bar and a thermometer, 400 parts of [Low molecular weight polyester 1], 110 parts of carnauba wax and 947 parts of ethyl acetate were charged, heated to 80 ° C. with stirring, and maintained at 80 ° C. for 5 hours. Thereafter, it was cooled to 30 ° C. at 1 hour. Next, 500 parts of [Masterbatch 1] and 500 parts of ethyl acetate were charged in a container and mixed for 1 hour to obtain [Raw material solution 1].
[Raw material solution 1] 1324 parts are transferred to a container, and using a bead mill (Ultra Visco Mill, manufactured by Imex Co., Ltd.), a liquid feeding speed is 1 kg / hr, a disk peripheral speed is 6 m / sec, and 0.5 mm zirconia beads are 80% by volume. The wax was dispersed under the conditions of filling and 3 passes. Next, 1324 parts of a 65% ethyl acetate solution of [low molecular weight polyester 1] and 34 parts of the above [inorganic fine particles 1] were added, followed by one pass with a bead mill under the above conditions to obtain [Pigment / Wax Dispersion 1]. The solid content concentration of [Pigment / Wax Dispersion 1] (130 ° C., 30 minutes) was 50%.

(Production Example 14)
~ Emulsification ~
[Pigment / Wax Dispersion 1] 648 parts, [Prepolymer 1] 154 parts, [Ketimine Compound 1] 8.5 parts in a container, TK homomixer (manufactured by Tokushu Kika) at 5,000 rpm for 1 minute After mixing, 1200 parts of [Aqueous Phase 1] was added to the container and mixed with a TK homomixer at a rotation speed of 10,000 rpm for 20 minutes to obtain [Emulsion Slurry 1].
That is, it is dispersed in an aqueous medium containing resin fine particles and an elongation reaction is performed.

(Production Example 15)
~ Solvent removal ~
[Emulsion slurry 1] was put into a container equipped with a stirrer and a thermometer, and after removing the solvent at 30 ° C for 8 hours, aging was performed at 45 ° C for 4 hours to obtain [Dispersion slurry 1].

(Production Example 16)
~ Washing and drying ~
[Dispersion Slurry 1] After filtering 100 parts under reduced pressure,
(1): 100 parts of ion-exchanged water was added to the filter cake, mixed with a TK homomixer (10 minutes at 12,000 rpm), and then filtered.
(2): 1O parts of 10% sodium hydroxide aqueous solution was added to the filter cake of (1), mixed with a TK homomixer (30 minutes at 12,000 rpm), and then filtered under reduced pressure.
(3): 100 parts of 10% hydrochloric acid was added to the filter cake of (2), mixed with a TK homomixer (rotation speed: 12,000 rpm for 10 minutes), and then filtered.
(4): 300 parts of ion-exchanged water was added to the filter cake of (3), mixed with a TK homomixer (rotation speed: 12,000 rpm for 10 minutes), and then filtered twice to obtain a cake. . This is designated as [Filter cake 1].
[Filter cake 1] was dried at 45 ° C. for 48 hours in a circulating dryer. Thereafter, the mixture was sieved with a mesh of 75 μm to obtain [Base toner E] having a weight average particle diameter of 6.5 μm.

(Production Example 17)
-Immobilization of charge control agent and inorganic fine particles-
100% by mass of [base toner E] and 1.5 parts of a charge control agent (Bontron E-84, manufactured by Orient Chemical Industry Co., Ltd.) are charged into a Q-type mixer (Mitsui Mining Co., Ltd.), and the peripheral speed of the turbine type blade is 50 m. The mixing process was set to / sec. The mixing operation was performed for 2 minutes, 5 cycles of 1 minute pause, and the total treatment time was 10 minutes.
Further, 1.8 % by mass of silica (H-2000, manufactured by Clariant Japan) and 1.2% by mass of silica ( RX-50, manufactured by Nippon Aerosil) were added and mixed. In the mixing operation, the peripheral speed was 15 m / sec, mixing for 30 seconds and resting for 1 minute were performed for 5 cycles to obtain [Toner T9]. [Toner T9] had a weight average particle diameter of 6.5 μm, a powder wall disintegration angle of 55 °, an aggregation degree of 13%, and a loose apparent density of 0.40 g / cm ³ .

(Production Example 18 to Production Example 20)
~ Preparation of base toner F ~ base toner H ~
[Mother toner F] to [Mother toner H] having different weight average particle diameters were obtained by sequentially changing the rotation number / time of the TK homomixer in the emulsification step and the temperature / time in the solvent removal step.

-Production of Toner T10 to Toner T14-
In Production Example 17, [Toner T10] to [Toner T14] were produced in the same manner as in Production Example 17 except that the base toner and additives shown in Table 3 were used for the formulation.
Table 3 also shows the weight average particle diameter, powder wall collapse angle, degree of aggregation, and loose apparent density of [Toner T10] to [Toner 14].

Example 1
A copy test was conducted using “IMAIO NEO C320” manufactured by Ricoh, and image evaluation was performed. In this embodiment, [cartridge C1] is used as the toner cartridge and [toner T1] is used as the toner. The evaluation results are shown in Table 4.

(Example 2 to Example 9)
In Example 1, image evaluation was performed in the same manner as in Example 1 except that any one of [Toner 2] to [Toner 5] and [Toner 9] to [Toner 12] was used as the toner. The evaluation results are shown in Table 4.

(Comparative Examples 1 to 5)
The cartridge C1] or [cartridge C2 as the toner cartridge in Example 1, except using either [Toner 1] to [toner 14] As the toner was performed image evaluation in the same manner as in Example 1 . The evaluation results are shown in Table 4.

<Image evaluation>
Details of the image evaluation described in Table 4 are shown below. In the copy test, toner replenishment was repeated 6 times, and a 100,000-color full color mode was performed. The image quality of the obtained image was visually evaluated for the presence or absence of background stains, white streak images, and the like. In each item, an image chart having a 3% image area was continuously run up to 100,000 sheets, and the following evaluation was performed.
(1) The background soiled white paper image is stopped during development, the developer on the photoconductor after development is transferred to tape, and the difference from the image density of the untransferred tape is determined by 938 Spectrodensitometer (manufactured by X-Rite) ).
(2) White streaks and thin layer formation Immediately after the start of the copy test and after 100,000 copies were made, the toner carrier thin layer formation and the presence of white streak images were evaluated according to the following criteria.
[Evaluation criteria]
: Uniform and good condition.
Δ: Some white streaks with a width of less than 0.3 mm are observed, but streaks are not clearly seen in the image.
X: A white streak having a width of 0.3 mm or more is generated, and the image is clearly missing as a white streak in the image.
(3) Filming The presence or absence of toner filming on the developing sleeve or the photoreceptor was observed and evaluated according to the following criteria.
[Evaluation criteria]
: No filming.
Δ: Line-like filming is observed ×: Filming is present as a whole.

As shown in Table 4, in Examples 1 to 9 using the toner according to the present invention, good results were obtained with no background dirt, white streaks, filming, etc. even during long-term use.
On the other hand, in Comparative Examples 1 to 3, a cartridge not provided with a rib as a return promoting means is used, and although there is no problem with the quality in the initial stage, the quality such as background dirt and white stripes in the long-term use. This resulted in deterioration.
Further, in Comparative Examples 4 and 5, since the powder wall collapse angle of the toner is outside the specified range of the present invention, quality deterioration such as background stains and white stripes was observed with use over time.

1 is a diagram illustrating a schematic configuration of a developing device according to a first embodiment of the present invention. FIG. 2 is a diagram schematically illustrating a configuration inside a toner cartridge and a developing hopper of the developing device according to the first embodiment. FIG. 6 is a diagram illustrating a movement of toner in a toner cartridge accompanying rotation of a second transport paddle. It is a figure for demonstrating the measuring method of the powder wall collapsing angle of a toner. It is a figure which shows schematic structure of the developing device which concerns on 2nd embodiment of this invention. It is the schematic which shows the structure of the control valve arrange | positioned at the image development unit in the image development apparatus of this invention. FIG. 10 is a diagram schematically illustrating a state in which toner is supplied from the toner cartridge side to the developing unit in the developing device according to the second embodiment. FIG. 5 is a diagram schematically illustrating toner movement between a developing unit and a toner cartridge. FIG. 5 is a diagram schematically illustrating toner movement between a developing unit and a toner cartridge. FIG. 5 is a diagram schematically illustrating toner movement between a developing unit and a toner cartridge. 1 is a schematic diagram illustrating a configuration of an image forming apparatus of the present invention. 4A and 4B are schematic views showing the configuration of the communication port 33 in the developing device of the present invention, where FIG. 5A shows the configuration on the developing unit 31 side, and FIG. 5B shows the configuration on the toner cartridge side. [Cartridge C1] is a sectional view showing an internal structure. [Cartridge C2] is a cross-sectional view showing an internal structure.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 11 Photoconductor 12 Photoconductor cleaning unit 13 1st charging means 14 Drive roller (photoconductor)
15, 16 Followed roller (photosensitive member)
20 exposure means 21 registration roller 25 paper feed roller 26 contact / separation mechanism 30 developing device 30 ′ developing device 31 developing unit 31a developing sleeve 31b supply roller 31c regulating roller 31d first transport paddle 31e slide shutter 31f elastic member 31g window portion 32 toner cartridge 321 First storage chamber 322 Second storage chamber 32a Second transport paddle 32b Third transport paddle 32c Slide shutter 32d Elastic member 32e Fixed seal 33 Communication port 34 Control valve 34a Support section 34b Film 35 Rib 40 Intermediate transfer belt unit 41 Intermediate transfer Belt 42 Belt cleaning unit 43 Mark sensor 44 Drive roller (intermediate transfer belt)
45 Primary transfer bias rollers 46, 47 Followed roller 49 Belt position detection mark 50 Secondary transfer unit 51 Secondary transfer bias roller 60 Fixing means 70 Double-sided transport device 80 Paper feed device 81 Paper feed roller 83 Manual feed tray 90 Transfer material

Claims (5)

In an image forming apparatus that includes at least a latent image carrier and a developing device that forms and develops a toner image on the latent image carrier, and fixes the toner image to a fixing medium.
The developing device includes at least a developing unit that supplies toner to the image forming unit;
A cartridge portion for supplying toner to the developing unit;
A hopper that temporarily stores toner to be supplied to the developing unit from the cartridge part, and the hopper part from a supply hole provided in an inner wall that separates the cartridge part and the hopper part Is a developing device in which a part of the toner can be returned into the cartridge portion,
The cartridge unit includes at least a rotating body that stirs / moves the toner, and a return promoting means that promotes the return of the toner to the inside of the cartridge in contact with the rotating body,
The rotating body is made of a single bendable film, and the return promoting means is a plate-like member provided on the inner wall of the cartridge part.
When the film rotates and hits the plate member, the toner is blocked by the plate member, and a toner-free space is formed between the plate member and the film. When a part of the toner moves into the space, a part of the toner in the hopper is returned into the cartridge part.
On the toner surface, inorganic fine particles having at least two kinds of particle diameters are attached,
The particle size of the two kinds of inorganic fine particles is 30~80m ² / g and 100 to 250 m ² / g in BET specific surface area,
The amount of the inorganic fine particles added for each particle size is 0.1 to 3.0 parts by weight with respect to 100 parts by weight of the toner base, and the total amount of the inorganic fine particles added is 100 parts by weight of the toner base. 1.3 to 3.2 parts by weight,
The toner is put into a cylindrical container without an upper bottom, and after standing, the cylindrical container is lifted and the toner is separated from the cylindrical container. A line segment connecting one point of the two points, a line segment connecting the two points of the peak of the toner and one point located on the side closer to the one point of the peak, and a line segment connecting the two points of the peak An image forming apparatus, wherein a powder wall disintegration angle is 30 ° to 70 °. The image forming apparatus according to claim 1.
The image forming apparatus, wherein the developing device uses toner having a cohesion degree in the range of 6 to 15%. The image forming apparatus according to claim 1, wherein
The image forming apparatus, wherein the developing device uses toner having a loose apparent density in a range of 0.35 to 0.50. At least a developing unit for supplying toner to the image forming unit;
A cartridge portion for supplying toner to the developing unit;
In a developing device having a hopper portion that temporarily stores toner supplied from the cartridge portion to the developing unit,
The developing device has a supply hole in a wall existing between the chamber of the cartridge unit and the chamber of the hopper unit, and a part of the toner in the hopper unit is returned to the cartridge unit through the supply hole. In a possible developing device,
The cartridge unit includes at least a rotating body that stirs / moves the toner, and a return promoting means that promotes the return of the toner into the cartridge unit in contact with the rotating body,
The rotating body is made of a single bendable film, and the return promoting means is a plate-like member provided on the inner wall of the cartridge part.
When the film rotates and hits the plate member, the toner is blocked by the plate member, and a toner-free space is formed between the plate member and the film. When a part of the toner moves into the space, a part of the toner in the hopper is returned into the cartridge part.
On the toner surface, inorganic fine particles having at least two kinds of particle diameters are attached,
The particle size of the two kinds of inorganic fine particles is 30~80m ² / g and 100 to 250 m ² / g in BET specific surface area,
The amount of the inorganic fine particles added for each particle size is 0.1 to 3.0 parts by weight with respect to 100 parts by weight of the toner base, and the total amount of the inorganic fine particles added is 100 parts by weight of the toner base. 1.3 to 3.2 parts by weight,
The toner is put into a cylindrical container without an upper bottom, and after standing, the cylindrical container is lifted and the toner is separated from the cylindrical container. A line segment connecting one point of the two points, a line segment connecting the two points of the peak of the toner and one point located on the side closer to the one point of the peak, and a segment connecting the two points of the peak The developing device characterized in that the formed powder wall powder wall collapse angle is 30 ° to 70 °. The image bearing member on which the electrostatic latent image is formed and the developing device that develops the electrostatic latent image formed on the surface of the image bearing member with a developer containing toner and forms a toner image are integrally supported. In the process cartridge formed detachably on the image forming apparatus main body,
5. The developing device according to claim 4, wherein the developing device is a developing device.
A process cartridge characterized by that.

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