JP2010102269A - Powder conveying device, process cartridge, and image forming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a powder conveying device suppressing generation of aggregates of powder, such as toner inside a conveyance pipe, and to provide a process cartridge and an image forming device each equipped with the conveying device. <P>SOLUTION: A drive motor 41Y is reversely driven at a predetermined timing, such as print operation ending of high-quality area consecutive printing (consecutive supply) at startup of the image forming device, a conveyance coil 70Y is reversely rotated, and as indicated by an arrow D, toner T is made conveyable in the reverse direction of the conveyance direction (C direction). Thereby, even when the toner is accumulated in a toner conveyance pipe 43Y and made dense, the conveyance coil 70Y is reversely driven to release density of the toner, the generation of aggregates of the toner is suppressed, and the toner can be appropriately supplied to a developing device 5Y. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  In the present invention, a powder such as toner used in an image forming apparatus such as a copying machine, a facsimile machine, or a printer is passed from a powder container to a powder transport tube, and is transported below the powder container. The present invention relates to a powder conveying apparatus that conveys toward the surface, a process cartridge including the same, and an image forming apparatus.

2. Description of the Related Art Conventionally, image forming apparatuses such as copying machines, facsimile machines, and printers are known that use a toner conveying device that conveys toner, which is powder, from a toner container to a developing device. This toner conveying device connects the toner container with a toner discharging means for discharging toner from the toner container and a developing device for developing a latent image carried on an image carrier such as a photoconductor into a toner image. It has a transport pipe. The toner discharging means is operated as necessary to discharge the toner stored in the toner container into the transport pipe and transport the toner into the developing device through the transport pipe.
In an image forming apparatus using such a toner conveying device, it is assumed that the toner container is disposed at a position lower than the developing device. In this case, it is necessary to transport the toner, which is a powder passed from the toner container into the transport pipe, toward the developing device so as to be lifted against the gravity, so that the transport efficiency is deteriorated or the toner is clogged in the transport pipe. It becomes easy. Therefore, the toner container is generally disposed at a position higher than the developing device so that the toner is conveyed in the direction of gravity.
As a toner conveyance device that performs such conveyance in the direction of gravity, for example, the one described in Patent Document 1 is known. In this toner conveying device, the toner discharged from the toner box, which is a toner container, into the conveying tube by the toner discharging means is dropped by its own weight and sent into the developing device.

However, in this toner transport device, there is a possibility that the toner discharged from the toner box into the transport tube accumulates on the inner wall of the transport tube and then flows into the developing device at once when the amount becomes a certain amount. When the toner is allowed to flow in this manner, it is difficult to accurately control the toner concentration of the two-component developer, for example, in the two-component development method using the two-component developer containing the toner and the magnetic carrier.
Further, for example, in a one-component development method using only toner without using a magnetic carrier, the proportion of toner that is not sufficiently frictionally charged in the developing device is increased at a stretch, and the toner is attached to the non-image portion of the image carrier. It becomes easy to cause so-called soiling. If the toner box and the developing device are arranged close to each other and the length of the transport pipe is made as short as possible so as not to accumulate toner, the rapid flow of toner from the transport pipe into the developing device can be suppressed. However, the degree of freedom of layout in the image forming apparatus is deteriorated due to the restriction of proximity arrangement.
Therefore, in order to stabilize the replenishment of powder without adversely affecting the layout of other devices, a rotating coil that applies a conveying force to the toner is disposed in the conveying tube, and further, It has been proposed to dispose an in-pipe powder passage restriction member (see, for example, Patent Document 2).
JP-A-8-30097 JP-A-2005-24665

In the device disclosed in Patent Document 2, a coil for conveying toner and a powder passage restricting member in the tube are arranged in the conveying tube, whereby an appropriate amount of toner is conveyed in the conveying tube, and the toner is rapidly fed into the developing device. Can be suppressed.
However, when the toner transported in the transport pipe remains in the transport pipe without being transported into the developing device, the toner is accumulated in the downstream of the transport pipe due to the weight of the toner from the upstream due to leaving, etc., and the toner aggregates. There is a case. When the transport coil is operated again, the toner that has become hard and aggregated is crushed into a lump that is clearly larger than the toner diameter (this state is hereinafter referred to as an aggregate), and is transported to the developing device. End up. As a result, the agglomerated toner may be directly sandwiched between developer doctors as developer regulating members in the developing device, resulting in poor developer conveyance (white streaks). As a result, agglomeration grows in the process of stirring in the developing device, which is a cause of generating abnormal images.

Such toner aggregation tends to reduce the particle size of toner used in recent years when the market demand for image quality improvement is increasing, tends to decrease the degree of accelerated aggregation (increase fluidity), and is easy to fluidize. Therefore, it tends to occur downstream. In particular, when printing a high-density image continuously, it is necessary to continuously replenish the toner in the developing device (continuous replenishment). Under such printing conditions, the transport coil rotates frequently (conditions Depending on the rotation, the fluidization phenomenon of the toner is accelerated, and further, the toner flows downstream and easily accumulates in the conveyance tube. As a result, there is a problem that the toner that has flowed in tends to cause a phenomenon that the toner flows away due to being left unattended.
The present invention has been made in consideration of the above circumstances, and a powder conveying apparatus capable of suppressing the generation of powder agglomerates such as toner in a conveying pipe, a process cartridge including the same, and image formation An object is to provide an apparatus.

In order to solve the above-mentioned problems, the invention of claim 1 includes a powder container for storing powder, and a powder for guiding the powder from the powder container to a transport destination below the powder container. A conveying pipe, a powder conveying member which is accommodated in the powder conveying pipe and moves to the powder by a moving force that moves to the downstream side in the conveying direction by a rotational motion, and the powder conveying member In a powder conveying apparatus, comprising: a driving unit that rotates a member; and a control unit that controls the driving unit, and the powder in the powder container is passed through the powder conveying tube to the conveying destination. The driving means is rotatable in forward and reverse directions, and the control unit conveys the powder to the upstream side in the conveying direction by driving the driving means in reverse at a predetermined timing.
Further, the invention of claim 2 is the powder transfer apparatus according to claim 1, wherein the internal space volume is reduced to at least a part of the internal space of the powder transfer tube via the powder transfer member. It is characterized in that a space regulating member is provided.
According to a third aspect of the present invention, in the powder conveying device according to the first or second aspect, the powder conveying member is a resin coil.
According to a fourth aspect of the present invention, in the powder conveyance device according to any one of the first to third aspects, the powder is toner used in an image forming apparatus.

According to a fifth aspect of the present invention, in the powder conveying apparatus according to the fourth aspect, the toner is a toner having an accelerated aggregation degree of 40% or less.
According to a sixth aspect of the present invention, in the powder conveyance device according to the fourth or fifth aspect, the toner is a toner having an average circularity of 0.90 or more.
The invention according to claim 7 is the powder conveying apparatus according to any one of claims 4 to 6, wherein the toner has a volume average particle diameter of 3 to 8 μm, a volume average particle diameter (Dv), and a number. The toner is characterized in that the ratio (Dv / Dn) to the average particle diameter (Dn) is in the range of 1.00 to 1.40.
The invention according to claim 8 is the powder conveying apparatus according to any one of claims 4 to 7, wherein the toner includes at least a polyester prepolymer having a functional group containing a nitrogen atom, a polyester, a colorant, A toner containing a toner obtained by crosslinking and / or stretching reaction of a toner material liquid in which a release agent is dispersed in an organic solvent in an aqueous medium.

According to a ninth aspect of the present invention, an image carrier that carries an electrostatic latent image and a developer containing at least toner are accommodated, and the toner in the developer is added to the electrostatic latent image of the image carrier. A process cartridge integrally configured with a developing device that supplies the electrostatic latent image to a toner image, wherein the process cartridge is a powder that conveys the toner from a toner storage container that stores the toner to the developing device. A powder conveyance device is provided, and the powder conveyance device is the powder conveyance device according to any one of claims 5 to 8.
According to a tenth aspect of the present invention, an image carrier that carries an electrostatic latent image and a developer containing at least toner are accommodated, and the toner in the developer is added to the electrostatic latent image of the image carrier. An image forming apparatus comprising: a developing device that supplies the electrostatic latent image to a toner image; and a powder conveying device that conveys the toner from a toner storage container that stores the toner to the developing device. The body conveyance device is a powder conveyance device according to any one of claims 5 to 8.
According to an eleventh aspect of the present invention, in the image forming apparatus according to the tenth aspect, the image carrier and the developing device are a process cartridge configured integrally.

  According to the present invention, the powder conveying member includes the rotation in the direction of generating the moving force moving downstream in the conveying direction, and the means for rotating in the direction opposite to the rotating direction, and the reverse at a predetermined timing. Powder conveying device capable of suppressing the generation of agglomerates of powder such as toner in a conveying tube by being controlled to rotate in the direction, a process cartridge including the same, and image formation An apparatus can be provided.

The inventors of the present invention have made various studies to suppress the generation of powder agglomerates such as toner. As one proposal, a space regulating member for reducing the volume of the internal space is disposed via a transfer coil in at least a part of the internal space that leads to the transfer destination below the powder transfer tube, and the inside of the transfer tube is transferred. It was considered that the amount of toner to be controlled is controlled to suppress the flow of toner in the conveyance tube, and to suppress the occurrence of toner clogging in the toner remaining in the conveyance tube due to the flow of toner.
However, the arrangement of the space regulating member in the transport pipe may cause a phenomenon that the toner is clogged in the reduced space. That is, when a toner having a reduced particle size and improved fluidity is used, the toner is clogged in the reduced space, and the clogged toner is likely to be clogged. It has been found that there is a case where the toner tightness is accelerated when the toner is in a state of being discharged.
As described above, when the toner clogging occurs, not only the above-described abnormal image is generated, but also the toner is easily clogged in the conveyance tube. When the toner is clogged in the conveyance tube, the torque applied to the conveyance coil increases. This leads to problems that lead to breakage of the transfer coil.

As a result of further examination of this phenomenon, in the case of high-image area continuous printing (continuous replenishment), the fluidized toner enters the space confined between the transport tube and the space regulating member, so the printing operation is completed. Later, when the toner settles in the narrow space and the toner runs out in this state, the torque applied to the transport coil increases. In the worst case, the conveyance coil is broken. That is, the outer diameter of the transfer coil is set smaller than the inner diameter of the transfer tube, and has a degree of freedom in the clearance therebetween. When the space regulating member is arranged in the transport pipe, the degree of freedom is reduced, and the space where the toner enters is also regulated (reduced).
Since the toner that has entered the reduced space has a low degree of freedom as in the case of the transport coil, it tends to settle down in a narrow space, and tends to be in a closed state. For this reason, if the toner is clogged in the transport tube, the torque applied to the transport coil increases, leading to a problem that leads to breakage of the transport coil.
In order to solve such a problem, the inventors of the present invention as a result of study, by temporarily reversing the transport direction of the transport coil from the downstream side to the upstream side at a predetermined timing such as after the end of the printing operation, The toner is transported to a non-sedated space (upstream), and the toner aggregation is loosened along with this transport, so that the toner coagulation state is eliminated and the toner aggregation is suppressed, and the torque to the transport coil is reduced. It has been found that the increase in the thickness of the carrier coil can be prevented and breakage of the transfer coil can be prevented, and the present invention has been completed.

Hereinafter, embodiments according to the present invention will be described.
First, an electrophotographic printer (hereinafter simply referred to as a printer) will be described as an example of an embodiment of an image forming apparatus to which the present invention is applied. First, the basic configuration of the printer will be described.
FIG. 1 is a schematic configuration diagram of the printer. In FIG. 1, the printer 100 includes four process cartridges 6Y, 6M, 6C, and 6K for generating toner images of yellow, magenta, cyan, and black (hereinafter referred to as Y, M, C, and K). ing. These use different colors of Y, M, C, and K toners as image forming substances, but otherwise have the same configuration and are replaced when the lifetime is reached. Taking a process cartridge 6Y for generating a Y toner image as an example, as shown in FIG. 2, a drum cleaning device 2Y, a charge eliminating device (not shown), a charging device 4Y, and a developing device are disposed around a drum-shaped photoreceptor 1Y. The device 5Y and the like are assembled integrally with the photoreceptor 1Y.
The process cartridge 6Y can be attached to and detached from the main body of the printer 100, and the consumable parts can be replaced at once by extracting the process cartridge 6Y from the printer 100. In the process cartridge 6Y, as shown in the above embodiment, the drum cleaning device 2Y, the static eliminator (not shown), the charging device 4Y, and the developing device 5Y do not have to be integrated with the photoreceptor 1Y. The photosensitive member 1Y and the developing device 5Y or other devices such as the photosensitive member 1Y, the developing device 5Y, and the charging device 4Y may be integrated.

In the printer 100, the process cartridges 6Y, 6M, 6C, and 6K and the toner bottles 32Y, 32M, 32C, and 32K are configured to be separately detachable from the main body of the printer 100. 6M, 6C, 6K and toner bottles 32Y, 32M, 32C, 32K can be separately replaced independently, and toner bottles 32Y, 32M, 32C, 32K can be easily replaced.
As shown in FIG. 2, the charging device 4Y uniformly charges the surface of the photoreceptor 1Y that is rotated clockwise in the drawing by a driving unit (not shown). An electrostatic latent image for Y is formed and carried on the surface of the uniformly charged photoreceptor 1Y by exposure scanning with a laser beam L emitted from the exposure device 7 (see FIG. 1). The electrostatic latent image of Y is developed into a Y toner image by a developing device 5Y using Y toner, as will be described later.
Then, the Y toner image is intermediately transferred onto an endless intermediate transfer belt 8 that is transported in the direction of arrow A. The drum cleaning device 2Y removes the toner remaining on the surface of the photoreceptor 1Y after the intermediate transfer process. Further, the static eliminator neutralizes residual charges on the photoreceptor 1Y after cleaning. By this charge removal, the surface of the photoreceptor 1Y is initialized and prepared for the next image formation. In the other process cartridges 6M, 6C, and 6K, M, C, and K toner images are similarly formed on the photoreceptors 1M, 1C, and 1K, and are intermediately transferred onto the intermediate transfer belt 8.

In FIG. 1 shown above, an exposure device 7 is disposed below the process cartridges 6Y, 6M, 6C, 6K in the drawing. The exposure device 7 serving as a latent image forming unit applies laser light L corresponding to each color image emitted based on the image information to each of the photoreceptors 1Y, 1M, 1C, and 1K in the process cartridges 6Y, 6M, 6C, and 6K. To form an electrostatic latent image corresponding to each color image.
The exposure device 7 irradiates the photoconductor with a laser beam (L) emitted from a light source through a plurality of optical lenses and mirrors while scanning with a polygon mirror rotated by a motor.
On the lower side of the exposure apparatus 7 in the figure, paper supply means having a paper storage cassette 26, a paper supply roller 27 incorporated therein, a registration roller pair 28, and the like are disposed. The paper storage cassette 26 stores a plurality of transfer papers P as recording bodies, and a paper feed roller 27 is in contact with the uppermost transfer paper P.
When the paper feeding roller 27 is rotated counterclockwise in the drawing by a driving means (not shown), the uppermost transfer paper P is fed toward the rollers of the registration roller pair 28. The registration roller pair 28 rotationally drives both rollers to sandwich the transfer paper P, but temporarily stops rotating immediately after sandwiching. Then, the transfer paper P is sent out toward a later-described secondary transfer nip at an appropriate timing. In the sheet feeding unit having such a configuration, a conveying unit is configured by a combination of the sheet feeding roller 27 and the registration roller pair 28 corresponding to the timing roller. This transport means transports the transfer paper P from a paper storage cassette 26 serving as a storage means to a secondary transfer nip described later.

Above the process cartridges 6Y, 6M, 6C, and 6K in the drawing, an intermediate transfer unit 15 that moves the endless intermediate transfer belt 8 that is an intermediate transfer body while stretching is disposed. In addition to the intermediate transfer belt 8, the intermediate transfer unit 15 includes four primary transfer bias rollers 9Y, 9M, 9C, and 9K, a cleaning device 10, and the like.
A secondary transfer backup roller 12, a cleaning backup roller 13, a tension roller 14 and the like are also provided. The intermediate transfer belt 8 is endlessly moved counterclockwise (in the direction of arrow A) in the drawing by being driven by rotation of at least one of the rollers while being stretched around these three rollers. The primary transfer bias rollers 9Y, 9M, 9C, and 9K sandwich the intermediate transfer belt 8 that is moved endlessly in this manner from the photoreceptors 1Y, 1M, 1C, and 1K to form primary transfer nips, respectively. Yes.
In these methods, a transfer bias having a polarity opposite to that of toner (for example, plus) is applied to the back surface (loop inner peripheral surface) of the intermediate transfer belt 8. All the rollers except the primary transfer bias rollers 9Y, 9M, 9C, and 9K are electrically grounded. The intermediate transfer belt 8 sequentially passes through the primary transfer nips for Y, M, C, and K along with the endless movement thereof, and Y, M, and C on the photoreceptors 1Y, 1M, 1C, and 1K. , K toner images are superimposed and primarily transferred. As a result, a four-color superimposed toner image (hereinafter referred to as a four-color toner image) is formed on the intermediate transfer belt 8.

The secondary transfer backup roller 12 sandwiches the intermediate transfer belt 8 between the secondary transfer roller 19 and forms a secondary transfer nip. The four-color toner image formed on the intermediate transfer belt 8 is transferred to the transfer paper P at the secondary transfer nip. Untransferred toner that has not been transferred onto the transfer paper P adheres to the intermediate transfer belt 8 after passing through the secondary transfer nip. This is cleaned by the cleaning device 10.
In the secondary transfer nip, the transfer paper P is sandwiched between the intermediate transfer belt 8 and the secondary transfer roller 19 whose surfaces move in the forward direction, and conveyed in the opposite direction to the registration roller pair 28 side. The When the transfer paper P sent out from the secondary transfer nip passes between the rollers of the fixing device 20, the four-color toner image transferred to the surface is fixed by heat and pressure.
Thereafter, the transfer paper P is discharged out of the apparatus through a pair of paper discharge rollers 29. A stack unit 30 is formed on the upper surface of the printer body, and the transfer paper P discharged outside the apparatus by the discharge roller pair 29 is sequentially stacked on the stack unit 30.

  The configuration of the developing device 5Y in the process cartridge 6Y will be described with reference to FIG. The developing device 5Y includes a magnetic field generating means inside, and a developing sleeve 51Y as a developer carrying member that carries and conveys a two-component developer containing magnetic carrier particles and toner on the surface, and is carried on the developing sleeve 51Y. And a doctor 52Y as a developer regulating member that regulates the layer thickness of the developer conveyed. On the upstream side in the developer conveying direction of the doctor 52Y, a developer accommodating portion 53Y that accommodates the developer regulated by the doctor 52Y without being conveyed to the developing area facing the photoreceptor 1Y is formed. Further, adjacent to the developer accommodating portion 53Y, a toner accommodating portion 54Y for accommodating toner and a toner conveying screw 55Y for agitating and conveying the toner are provided.

Next, the operation of the developing device 5Y will be described. In the developing device 5Y, a developer layer is formed on the developing sleeve 51Y. Further, the toner is taken into the developer from the developer accommodating portion 53Y by the movement of the developer layer conveyed by the rotation of the developing sleeve 51Y. The toner is taken in so that the developer is within a predetermined toner density range. The toner taken into the developer is charged by frictional charging with the carrier. The developer containing charged toner is supplied to the surface of the developing sleeve 51Y having a magnetic pole inside and is carried by magnetic force.
The developer layer carried on the developing sleeve 51Y is conveyed in the arrow B direction as the developing sleeve 51Y rotates. On the way, after the thickness of the developer layer is regulated by the doctor 52Y, it is transported to the developing area facing the photoreceptor 1Y. In the development area, toner is supplied from the developer to the latent image formed on the photoreceptor 1Y to develop the latent image into a toner image. The developer layer remaining on the developing sleeve 51Y is conveyed to the upstream portion in the developer conveying direction of the developer accommodating portion 53Y as the developing sleeve 51Y rotates. In this embodiment, a two-component developer composed of a magnetic carrier and toner is used, but a one-component developer using only toner may be used.

In FIG. 1 described above, a bottle container 31 is disposed between the intermediate transfer unit 15 and the stack portion 30 located above the intermediate transfer unit 15. The bottle container 31 houses toner bottles 32Y, 32M, 32C, and 32K that contain Y, M, C, and K toners. The toner bottles 32Y, 32M, 32C, and 32K are installed on the bottle container 31 so as to be placed from above for each toner color. The Y, M, C, and K toners in the toner bottles 32Y, 32M, 32C, and 32K are appropriately transferred to the developing devices 5Y, 5M, 5C, and 5K of the process cartridges 6Y, 6M, 6C, and 6K, respectively, by a toner conveyance device described later. To be replenished.
These toner bottles 32Y, 32M, 32C, and 32K are detachable from the main body of the printer 100 independently of the process cartridges 6Y, 6M, 6C, and 6K. In the present embodiment, toner bottles 32Y, 32M, 32C, and 32K that contain only toner are used as replenishment toners. However, toner bottles 32Y, 32M, and 32C that contain a developer mixed with carrier and toner are used. 32K may be used.

FIG. 3 is a perspective view of the toner bottle 32Y. 4 is a perspective view of a state in which the toner bottle 32K is placed in the bottle container 31. FIG. As shown in FIG. 3, the toner bottle 32Y is provided with a resin case 34Y at the tip of the bottle body 33Y.
A handle 35Y is integrally formed with the resin case 34Y. Further, a gear 37 </ b> Y that rotates integrally with the bottle body 33 is provided on the resin case 34 </ b> Y side of the bottle body 33. When the toner bottle 32Y is attached to the main body of the printer 100, the stack unit 30 is first opened upward to expose the bottle container 31.
Then, as shown in FIG. 4, after the toner bottle 32Y is placed on the bottle container 31, the handle 35Y is rotated. Then, the resin case 34Y configured integrally with the handle 35Y rotates, and the shutter 36Y moves in the circumferential direction of the resin case 34Y to open and the toner discharge port (not shown) is opened. The bottle container 31 is connected and fixed.

On the other hand, in order to remove the toner bottle 32Y from the printer 100 main body, the handle 35Y is rotated in the reverse direction to release the connection between the resin case 34Y and the bottle container 31, and simultaneously the shutter 36Y is closed and the toner discharge port is opened. Closed. Then, the toner bottle 32Y can be taken out from the main body of the printer 100 while holding the handle 35Y. As described above, since the toner bottle 32Y can be placed and removed from the upper side of the printer 100 main body, the replacement operation of the toner bottle 32Y is easy to understand and can be easily performed. Further, since the handle 35Y is formed on the resin case 34Y, the resin case 34Y can be rotated and fixed to the bottle container 31 easily.
When the toner bottle 32Y is detached from the printer 100 main body, the shutter 36Y is not opened even if the handle 35Y of the resin case 34Y is rotated. As a result, it is possible to prevent the toner 36 from being accidentally opened when the toner bottle 32Y is replaced and the toner inside is spilled.

Next, the toner conveying unit will be described. FIG. 5 is a perspective view of the toner bottles 32Y, 32M, 32C, and 32K and the toner conveying devices 40Y, 40M, 40C, and 40K. FIG. 6 is a perspective view of the toner bottles 32Y, 32M, 32C, and 32K, the intermediate transfer unit 15, and the toner conveying devices 40Y, 40M, 40C, and 40K viewed from different angles.
The toner conveying devices 40Y, 40M, 40C, and 40K are provided on the printer 100 main body on the side of the intermediate transfer unit 15. For this reason, since it is not necessary to provide the toner conveying means in the process cartridges 6Y, 6M, 6C, 6K or the toner bottles 32Y, 32M, 32C, 32K, the process cartridges 6Y, 6M, 6C, 6K or the toner bottle 32Y are compared with the conventional ones. , 32M, 32C, 32K can be reduced. Further, since the conventional process cartridge and the toner bottle are arranged close to each other, there is a limitation in design, but in this embodiment, the process cartridge and the toner bottle can be arranged separately. Therefore, the degree of freedom in design is improved and the printer can be downsized.
Also, the toner bottles 32Y, 32M, 32C, and 32K discharge ports, toner transport devices 40Y, 40M, 40C, and 40K, and toner storage units 54Y, 54M, 54C, and 54K of the developing devices 5Y, 5M, 5C, and 5K A replenishing port is arranged on one side of the intermediate transfer unit 15. Therefore, the toner conveyance paths of the toner conveyance devices 40Y, 40M, 40C, and 40K can be shortened, and the printer can be downsized and clogging can be prevented during toner conveyance.

Since the toner transport devices 40Y, 40M, 40C, and 40K have the same configuration, the toner transport device 40Y for transporting Y toner will be described. In FIG. 5, the toner transport device 40Y is mainly composed of a drive motor 41Y, a drive gear group 42Y, and a toner transport pipe 43Y which is a powder transport pipe. Inside the toner transport pipe 43Y, a resin transport coil (not shown) for transporting the toner to the downstream developing device 5Y is provided. One of the drive gear groups 42Y meshes with the gear 37Y of the toner bottle 32Y. When the drive motor 41Y is rotated, the bottle body 33Y that rotates integrally with the gear 37Y of the toner bottle 32Y rotates. When the density detection sensor 56Y of the developing device 5Y shown in FIG. 2 detects that the toner density is insufficient in the toner storage portion 54Y, the drive motor 41Y is rotated by a replenishment signal from the control portion 57Y.
In FIG. 5, since the spiral developer guide groove 38Y is formed on the inner surface of the inner wall of the bottle main body 33Y, the toner inside is conveyed from the back side of the bottle main body 33Y to the resin case 34Y side at the tip by rotation. Then, the toner in the bottle body 33Y falls from a discharge port (not shown) of the resin case 34Y to a toner receiving portion 44Y (see FIG. 8), which will be described later, which is a powder storage portion of the toner transport device 40Y.

The toner receiver 44Y is connected to the toner transport pipe 43Y. When the drive motor 41Y is rotated, the bottle main body 33Y rotates and at the same time, the rotating shaft 71 having a gear 72Y meshed with one of the drive gear groups 42Y described later. The transport coil 70Y (see FIG. 8) in the toner transport pipe 43Y connected to (see FIG. 8) rotates simultaneously. The toner T dropped on the toner receiving portion 44Y by the rotation of the transport coil 70Y is transported in the toner transport pipe 43Y and replenished to a toner replenishing port (not shown) of the toner storage portion 54Y of the developing device 5Y. In this way, the toner density in the developing device 5Y is adjusted.
In place of the density detection sensor 56Y, a reference image is formed on the photoreceptor 1Y, and an optical sensor or a CCD camera is provided for measuring the number of pixels of the reference image, and toner is replenished based on the measurement result. May be performed.

Next, toner conveyance of the toner conveyance device according to the first embodiment of the present invention will be described. FIG. 7 is an enlarged configuration diagram showing a part of the toner conveying device according to the first embodiment of the present invention. FIG. 8 is a schematic diagram showing a cross-sectional structure of the toner conveying device according to the first embodiment of the present invention.
In the present embodiment, as shown in FIG. 8, a conveying coil 70Y as a powder conveying member is connected to a rotating shaft 71Y at one end, and the conveying coil 70Y is connected to a toner conveying pipe 43Y as a powder conveying tube. It is installed in contact with the inner wall. The gap between the toner transport pipe 43Y and the transport coil 70Y is about 0.1 to 0.2 mm. The rotation shaft 71Y of the drive gear group 42Y (see FIG. 5) meshes with a gear (not shown) attached to the rotation shaft of the drive motor 41Y by the rotation of the drive motor 41Y (see FIG. 5) as drive means. It is rotated by rotational drive.
In this case, it is possible to rotate the rotation shaft 71Y via the gear 72Y meshing with one of the drive gear groups 42Y to incline the conveyance coil 70Y. In this case, the drive motor 41Y can be rotated forward and backward, and the toner T supplied from the bottle main body 33Y as indicated by the arrow B through the opening 44Ya of the toner receiving portion 44Y is transferred to the lower developing device 5Y (not shown). When the toner is transported through the opening 43Ya of the toner transport pipe 43Y, the drive motor 41Y is driven to rotate in the forward direction to apply a force for moving the toner T in the toner transport pipe 43Y in the direction indicated by the arrow C.

On the other hand, when the image forming apparatus is started up, the drive motor 41Y is reversely driven at a predetermined timing such as when the printing operation of high image area continuous printing (continuous replenishment) is completed, and the conveying coil 70Y is reversely rotated to be indicated by an arrow D. In addition, the toner T can be transported in the direction opposite to the transport direction (C direction). In this way, as shown in FIG. 7, the drive motor 41Y is normally driven by the replenishment signal from the control unit 57Y when it detects the lack of toner density from the density detection sensor 56Y.
On the other hand, the control unit 57Y causes the drive motor 41Y to be driven in reverse by a detection signal from the detection unit 58 that detects when the image forming apparatus is started up or when a printing operation of high image area continuous printing (continuous replenishment) ends. I have control. Therefore, when the image forming apparatus is turned off from the previous night and the toner is left in the toner transport pipe 43Y for a certain period of time, the image forming apparatus is started up or printing operation for continuous high-image area printing (continuous replenishment) is performed. When the toner T1 is stored in the horizontal portion 43Yb on the downstream side of the toner transport pipe 43Y at the end or the like, the printing operation state is detected, and the toner T1 is detected by the reverse rotation of the transport coil 70Y. The toner T1 is temporarily reversely sent upstream (in the direction of arrow D), and the toner T1 can be released.

Such reverse rotation driving of the conveying coil 70Y can properly unwind the toner T1 as long as it is performed once or more. The excessively long reverse rotation is preferably within 10 revolutions because the toner T in the toner transport pipe 43Y runs out and the toner supply during the next operation becomes insufficient. Incidentally, in this embodiment, the reverse rotation time is 0.3 seconds when the rotation speed of the transfer coil 70Y is 200 rpm. In this case, one of the drive gear groups 42Y that meshes with the gear 37Y of the toner bottle 32Y is idled by a clutch mechanism or the like, and the reverse drive of the drive motor 41Y is not transmitted to the gear 37Y of the toner bottle 32Y. The rotation of the bottle 32Y is prevented and the toner supply from the toner bottle 32Y to the toner receiving portion 44Y is stopped.
In the present embodiment, a resin-made conveyance coil 70Y is used as a toner conveyance member. However, even if a conveyance means having a shaft such as a screw is used instead of the conveyance coil 70Y, a straight line may be used. It may be possible to transport toner in a transport path that does not exist. In particular, the straight portion such as the horizontal portion 43Yb of the toner conveyance pipe may be provided with a screw-shaped conveyance member. However, when the conveying means having a shaft and the conveying coil are compared, the conveying coil is easier to bend.
For this reason, the use of the conveying coil reduces the force repelling deformation when rotating in the curved portion in the toner conveying pipe 43Y. Therefore, the use of the conveying coil 70Y can reduce the sliding load with the toner conveying pipe 43Y as compared with the case where the conveying means having the shaft is used.

In the present embodiment, the resin-made transport coil 70Y is used as the toner transport member, but a metal-made transport coil can also be used. When a metal transfer coil is used, a resin transfer coil is suitable because there is a risk of breakage due to fatigue.
That is, when the transport coil 70Y is disposed in the toner transport pipe 43Y having a winding path having the bent portions 43c1, 43c2 and the inclined portion 43d as shown in FIG. 8, the bent portions 43c1, 43c2 The transfer coil portion arranged in is subjected to repeated stress. Therefore, when it receives repeated stress, it may break with relatively small stress regardless of metal or resin. However, in the case of a metal, since the rigidity is higher than that of a resin, the stress received is increased, and there is one surface that is easily broken.
Therefore, in the case of the present embodiment in which the torque received by the transfer coil 70Y is originally small, it is possible to appropriately prevent breakage due to repeated stress even in a winding transfer path by using a resin material. Therefore, a material having high fatigue strength that is received by bending of the conveyance path is preferable. An example is PET (polyester resin) material. However, since the strength against a single stress is higher in the metal than in the resin, the metal may have better resistance when the toner is stuck and the torque is increased.

Next, a toner transport device according to a second embodiment of the present invention will be described with reference to FIGS. FIG. 9 is a schematic diagram showing a cross-sectional structure of a toner conveying device according to the second embodiment of the present invention. FIG. 10 is a cross-sectional view in which the inclined portion of the toner transport pipe is partially cut away when the transport coil of the toner transport device shown in FIG. 9 is driven forward, and FIG. 11 is a transport coil of the toner transport device shown in FIG. FIG. 6 is a cross-sectional view in which the inclined portion of the toner transport pipe is partially cut out when the toner is reversely driven.
In the toner transport device according to the first embodiment described above, the toner supply from the toner bottle 32Y is performed from the toner discharge port (not shown) toward the toner transport device 40Y every time the toner bottle 32Y rotates once. Is called. Since the toner is replenished every rotation, the amount of toner replenished at one time is larger than the amount of toner transported by the transport coil 70Y. Since the toner exceeding the transport amount of the transport coil 70Y has a space in the center of the transport coil 70Y, the toner flows through the space in the center of the transport coil 70Y and reaches the developing device 5Y regardless of the rotation of the transport coil 70Y. .
As a result, a large amount of toner is replenished to the developing device 5Y every time the toner bottle makes one rotation, and the toner concentration in the developing device 5Y increases rapidly, which may cause problems such as background contamination.

In the toner transport device according to the second embodiment, in order to prevent problems caused by the Y toner accumulated in the toner transport pipe 43Y flowing into the developing device 5Y of the toner transport device according to the first embodiment at once. A rod-shaped space regulating member 73 made of a flexible resin is loaded in the internal space 43Ye in the inclined portion 43Yd of the toner transport pipe 43Y to reduce the internal space volume of the toner transport pipe 43Y.
By loading this space regulating member 73 into the internal space 43Ye in the toner transport pipe 43Y of the inclined portion 43Yd, the transport amount of the toner T transported to the developing device 5Y is appropriately controlled and sent into the developing device 5Y at once. It is possible to suppress being paid.
However, as shown in FIG. 10, in the toner transport device according to the second embodiment, the toner T is transported by the transport coil 70 in the narrow clearance 74 between the inner surface of the toner transport pipe 43 </ b> Y and the outer surface of the space regulating member 73. Since the toner is transported to C, the toner T tends to be stored at the bottom of the inclined portion 43Yd of the toner transport pipe 43Y, and the toner is likely to be stuck. As a result, not only toner aggregates are likely to be formed, but also when toner clumps occur, the torque with respect to the transport coil 70Y increases and proper toner transport cannot be performed.

In the worst case, the transfer coil 70Y is damaged. Therefore, in the toner conveying apparatus according to the second embodiment, in the normal operation (forward rotation driving) of the conveying coil 70Y, the toner is sent downstream (in the direction of arrow C) at a predetermined timing such as after the end of the printing operation. As described above, the conveying coil 70Y is reversed to release the toner clumps, and the toner is temporarily conveyed upstream (in the direction of arrow D), and the amount of toner in the clearance 74 is appropriately controlled. The torque for the transfer coil 70Y is reduced. In this case, the number of reverse rotations of the transfer coil 70Y is 1 to 10 as in the case of the first embodiment.
The outer diameter of the space regulating member 73 used in the second embodiment is set to be slightly smaller than the inner diameter of the toner conveying pipe 43Y. When the conveying coil 70Y rotates, the outer restricting member 73 slides with the conveying coil 70Y. However, resistance is hardly generated, but the ability to restrict the passage of powder is increased. Incidentally, in the present embodiment, the inner diameter of the toner transport pipe 43Y is 5 mm (tolerance +0.05 mm / 0 mm), and the outer diameter of the space regulating member 73 is 4.5 mm (tolerance +0.05 mm / −0.05 mm). ) Is set.

Next, a toner transport device according to a third embodiment of the present invention will be described with reference to FIGS. FIG. 12 is a schematic diagram showing a cross-sectional structure of a toner conveying device according to the third embodiment of the present invention. FIG. 13 is an enlarged cross-sectional view of the main part of FIG.
In the toner conveying device according to the third embodiment, as shown in FIG. 12, a regulating portion 71Yb is added to the toner conveying device according to the second embodiment described above, and the developing device 5Y is connected to the toner conveying pipe 43Y. In this way, problems caused by flowing Y toner deposited on the surface at once are more reliably prevented. That is, as shown in FIG. 13, the toner receiving portion 44Y, which is the engaging portion 48Y between the toner transport pipe 43Y and the bottle body 33Y, regulates the replenishment amount of the toner T and is transported by the rotation of the transport coil 70Y. As described above, a restricting portion 71Yb for restricting the amount of toner passing through the toner transport pipe 43Y is provided from the other part of the toner transport pipe 43Y.
The toner receiving portion 44Y is provided with a rotating shaft 71Y that is rotated by one of the drive gear groups 42Y, and one end 70Ya of the conveying coil 70Y is bonded and fixed to the outer periphery of the rotating shaft 71Y. . Further, a region from the downstream end in the transport direction where the toner T is replenished from the bottle main body 33Y to the tip 71Ya of the rotation shaft 71Y on the downstream side in the transport direction is a region A. In the region A, the transport coil 70Y has one pitch or more. The restriction portion 71Yb is formed so as to be wound.

In the area A, the conveying coil 70Y is inscribed in the toner conveying pipe 43Y, the rotating shaft 71Y is inscribed in the conveying coil, and the conveying coil 70Y has one pitch or more, so that the gap through which the toner T can pass through the area A by its own weight. There is almost no. Therefore, no matter what timing the toner is discharged from the bottle main body 33Y, the toner T is blocked in the region A, and the toner can pass only by the rotation of the transport coil 70Y.
Although it is possible to prevent the toner T from temporarily flowing into the developing device 5Y by forming such a restricting portion 71Yb, the particle size of the toner is reduced in recent years when the market demand for image quality improvement is increasing. In such a toner, there is a tendency that the flow of the toner T to the developing device 5Y cannot be stopped temporarily. Therefore, along with the formation of the restricting portion 71Yb, the space restricting member 73 squeezed in the second embodiment described above can be disposed in the toner transport pipe 43Y to suppress the inflow of toner.
However, as described in the second embodiment, the toner T is transported in the transport direction C by the transport coil 70 in the narrow clearance 74 between the inner surface of the toner transport pipe 43Y and the outer surface of the space regulating member 73. At the bottom of the inclined portion 43Yd of the transport pipe 43Y, the toner T is easily stored, and the toner is liable to be stuck. In addition, when the toner is stuck, the torque with respect to the transport coil 70Y is increased, so that proper toner transport cannot be performed, and in the worst case, the transport coil 70Y is damaged.
Therefore, also in the toner conveying device according to the third embodiment, in the normal operation (forward rotation driving) of the conveying coil 70Y, the toner is sent to the downstream side (in the arrow C direction) as described above after the printing operation is completed. Then, the conveying coil 70Y is reversed to release the toner clumps, and the toner is temporarily conveyed upstream (in the direction of arrow D), and the amount of toner in the clearance 74 is appropriately controlled to increase the torque with respect to the conveying coil 70Y. I try to decrease.

Next, a toner transport device according to a fourth embodiment of the present invention will be described with reference to FIG. FIG. 14 is a schematic diagram showing a cross-sectional structure of a toner conveying device according to the fourth embodiment of the present invention.
In the toner conveying device according to the fourth embodiment, as shown in FIG. 14, as the space regulating member 73 of the toner conveying device according to the third embodiment, the inclined portion 43Yc and the horizontal portion 43Yb of the toner conveying pipe 43Y. The space restricting member 73 extending to is used. Accordingly, it is possible to reduce the amount of the stored toner T1 that is easily formed on the horizontal portion 43Yb of the toner transport pipe 43Y, thereby suppressing toner jamming.
However, also in the fourth embodiment, as in the case of the toner conveying device of the third embodiment described above, in recent years when the market demand for image quality improvement is increasing, the particle size of the toner is reduced and the acceleration aggregation degree is lowered ( In such a toner, the toner T is transported in the transport direction C by the transport coil 70Y in the narrow clearance 74 between the inner surface of the toner transport pipe 43Y and the outer surface of the space regulating member 73. In the inclined portion 43Yd and the horizontal portion 43Yb of the toner transport pipe 43Y, the toner T is easily stored, and the toner is easily stuck. In addition, when the toner is stuck, the torque with respect to the transport coil 70Y is increased, so that proper toner transport cannot be performed, and in the worst case, the transport coil 70Y is damaged.

Therefore, also in the toner conveying apparatus according to the fourth embodiment, in the normal operation (forward rotation driving) of the conveying coil 70Y, the toner is sent downstream (in the direction of arrow C) as described above after the printing operation is completed. Then, the conveying coil 70Y is reversed to release the toner clumps, and the toner is temporarily conveyed upstream (in the direction of arrow D), and the amount of toner in the clearance 74 is appropriately controlled to increase the torque with respect to the conveying coil 70Y. I try to decrease.
As described above, in the present invention, the drive motor 41Y is reversely driven at a predetermined timing such as when the image forming apparatus is started up and when the printing operation of high image area continuous printing (continuous replenishment) is completed, thereby conveying the coil 70Y. Since the toner T can be transported in the direction opposite to the transport direction (C direction) as shown by the arrow D, the transport is performed even if the toner is stored in the toner transport pipe 43Y and the jam occurs. The coil 70 </ b> Y can be driven in reverse to release the toner clumps, and the toner can be appropriately supplied to the developing device 5 </ b> Y by suppressing the generation of toner aggregates.

Next, the toner used in the toner conveying device as the powder conveying device according to the present invention will be described.
As an example of the toner used in the image forming apparatus according to the present invention, a toner having an accelerated aggregation degree of 40% or less is suitable. The accelerated aggregation degree is an index indicating the fluidity of the powder (toner), and a method for measuring the accelerated aggregation degree of the toner is described below.
(1) As a measuring device, a powder tester (registered trademark) manufactured by Hosokawa Micron is used.
(2) As a measurement method, the sample to be measured is left in a thermostatic chamber (35 ± 2 ° C. for 24 ± 1 hour). The sample to be measured left in this way is measured using the above powder tester. In this case, three types of sieves having different openings are used (for example, 75 μm, 44 μm, and 22 μm), calculated from the remaining amount of toner when sieved, and the aggregation degree is obtained by the following calculation.
((Weight of powder remaining on upper sieve) / (sampled amount)) × 100 (1)
((Powder weight remaining on the middle sieve) / (sample amount)) × 100 × 3/5 (2)
((Powder weight remaining on the lower sieve) / (sampled amount)) × 100 × 1/5 (3)
The sum of the above three calculated values is defined as the accelerated aggregation degree (%). As described above, the toner accelerated aggregation degree is an index obtained by stacking three types of meshes having different openings in the order of increasing openings, placing the uppermost particles, sieving with constant vibration, and calculating from the powder weight on each mesh. .

Further, as an example of the toner used in the image forming apparatus according to the present invention, a toner having an average circularity of 0.90 or more (a toner of 0.90 to 1.00) is used. This circularity is an index of the degree of unevenness of the toner particles, and indicates 1.00 when the toner is a perfect sphere, and the circularity becomes smaller as the surface shape becomes more complicated. When the average circularity is in the range of 0.90 to 1.00, the surface of the toner particles is smooth, and the toner particles and the contact area between the toner particles and the photosensitive member are small, so that the transferability is excellent.
Since the toner has no corners, the stirring torque of the developer in the developing device is small, and the driving of stirring is stabilized, so that no image is generated. Since there are no angular toner particles in the toner that forms dots, when the pressure is brought into contact with the transfer medium during transfer, the pressure is evenly applied to the entire toner that forms the dots, and transfer loss is less likely to occur. Since the toner particles are not angular, the abrasive power of the toner particles themselves is small, and the surfaces of the photoreceptor, the charging member and the like are not damaged or worn.

Next, a method for measuring the circularity will be described.
The circularity can be measured using a flow type particle image analyzer EPIA-1000 manufactured by Toa Medical Electronics. As a specific measuring method, 0.1 to 0.5 ml of a surfactant, preferably an alkylbenzene sulfonate, is added as a dispersant to 100 to 150 ml of water from which impure solids have been removed in advance. About 0.1 to 0.5 g. The suspension in which the sample is dispersed is subjected to dispersion treatment with an ultrasonic disperser for about 1 to 3 minutes, and the shape and particle size of the toner are measured by the above apparatus with the dispersion concentration being 3000 to 10000 / μl.
In order to reproduce a minute dot of 600 dpi or more, a toner having a weight average particle diameter of 3 to 8 μm is preferable. In this range, since the toner particles have a sufficiently small particle size with respect to the minute latent image dots, the dot reproducibility is excellent. When the weight average particle diameter (D4) is less than 3 μm, phenomena such as a decrease in transfer efficiency and a decrease in blade cleaning properties tend to occur.
When the weight average particle diameter (D4) exceeds 8 μm, it is difficult to suppress scattering of characters and lines. The ratio (D4 / D1) of the weight average particle diameter (D4) to the number average particle diameter (D1) is preferably in the range of 1.00 to 1.40. The closer (D4 / D1) is to 1.00, the sharper the particle size distribution. Such a toner having a small particle size and a narrow particle size distribution has a uniform toner charge amount distribution, and can provide a high-quality image with little background fogging. In addition, the electrostatic transfer method has a high transfer rate. can do.

Next, a method for measuring the particle size distribution of toner particles will be described.
Examples of the measuring device for the particle size distribution of toner particles by the Coulter counter method include Coulter Counter TA-II and Coulter Multisizer II (both manufactured by Coulter). The measurement method is described below.
First, 0.1 to 5 ml of a surfactant (preferably alkylbenzene sulfonate) is added as a dispersant to 100 to 150 ml of an aqueous electrolytic solution. Here, the electrolytic solution is a solution prepared by preparing a 1% NaCl aqueous solution using primary sodium chloride. For example, ISOTON-II (manufactured by Coulter) can be used. Here, 2 to 20 mg of a measurement sample is further added. The electrolytic solution in which the sample is suspended is subjected to a dispersion treatment with an ultrasonic disperser for about 1 to 3 minutes, and the measurement device is used to measure the weight and number of toner particles or toner using a 100 μm aperture as an aperture. Calculate weight distribution and number distribution. From the obtained distribution, the weight average particle diameter (D4) and the number average particle diameter (D1) of the toner can be obtained.
As channels, 2.00 to less than 2.52 μm; 2.52 to less than 3.17 μm; 3.17 to less than 4.00 μm; 4.00 to less than 5.04 μm; 5.04 to less than 6.35 μm; 6 .35 to less than 8.00 μm; 8.00 to less than 10.08 μm; 10.08 to less than 12.70 μm; 12.70 to less than 16.00 μm; 16.00 to less than 20.20 μm; Uses 13 channels of less than 40 μm; 25.40 to less than 32.00 μm; 32.00 to less than 40.30 μm, and targets particles having a particle size of 2.00 μm to less than 40.30 μm.

Examples of the toner used in the present invention include a toner material liquid in which at least a polyester prepolymer having a functional group containing a nitrogen atom, a polyester, a colorant, and a release agent are dispersed in an organic solvent. A toner obtained by crosslinking and / or elongation reaction in an aqueous solvent. Hereinafter, the constituent material and the manufacturing method of the toner will be described.
(polyester)
The polyester is obtained by a polycondensation reaction between a polyhydric alcohol compound and a polycarboxylic acid compound. Examples of the polyhydric alcohol compound (PO) include dihydric alcohol (DIO) and trihydric or higher polyhydric alcohol (TO). (DIO) alone or a mixture of (DIO) and a small amount of (TO) preferable. Examples of the dihydric alcohol (DIO) include alkylene glycol (ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,6-hexanediol, etc.); alkylene ether glycol (diethylene glycol) , Triethylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene ether glycol, etc.); alicyclic diols (1,4-cyclohexanedimethanol, hydrogenated bisphenol A, etc.); bisphenols (bisphenol A, bisphenol) F, bisphenol S, etc.); alkylene oxide (ethylene oxide, propylene oxide, butylene oxide, etc.) adduct of the above alicyclic diol; Alkylene oxide bisphenol (ethylene oxide, propylene oxide, butylene oxide, etc.), etc. adducts.

Among them, preferred are alkylene glycols having 2 to 12 carbon atoms and alkylene oxide adducts of bisphenols, and particularly preferred are alkylene oxide adducts of bisphenols and alkylene glycols having 2 to 12 carbon atoms. It is a combined use. As trihydric or higher polyhydric alcohol (TO), 3 to 8 or higher polyhydric aliphatic alcohol (glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, sorbitol, etc.); trihydric or higher phenols (Trisphenol PA, phenol novolak, cresol novolak, etc.); and alkylene oxide adducts of the above trivalent or higher polyphenols.
Examples of the polyvalent carboxylic acid (PC) include divalent carboxylic acid (DIC) and trivalent or higher polyvalent carboxylic acid (TC). (DIC) alone and (DIC) with a small amount of (TC) Mixtures are preferred. Divalent carboxylic acids (DIC) include alkylene dicarboxylic acids (succinic acid, adipic acid, sebacic acid, etc.); alkenylene dicarboxylic acids (maleic acid, fumaric acid, etc.); aromatic dicarboxylic acids (phthalic acid, isophthalic acid, terephthalic acid) And naphthalenedicarboxylic acid). Of these, preferred are alkenylene dicarboxylic acids having 4 to 20 carbon atoms and aromatic dicarboxylic acids having 8 to 20 carbon atoms. Examples of the trivalent or higher polyvalent carboxylic acid (TC) include aromatic polycarboxylic acids having 9 to 20 carbon atoms (such as trimellitic acid and pyromellitic acid). In addition, as polyhydric carboxylic acid (PC), you may make it react with polyhydric alcohol (PO) using the above-mentioned acid anhydride or lower alkyl ester (Methyl ester, ethyl ester, isopropyl ester, etc.).

  The ratio of the polyhydric alcohol (PO) to the polycarboxylic acid (PC) is usually 2/1 to 1/1, preferably as the equivalent ratio [OH] / [COOH] of the hydroxyl group [OH] and the carboxyl group [COOH]. Is 1.5 / 1 to 1/1, more preferably 1.3 / 1 to 1.02 / 1. The polycondensation reaction between a polyhydric alcohol (PO) and a polycarboxylic acid (PC) is carried out in the presence of a known esterification catalyst such as tetrabutoxytitanate or dibutyltin oxide, and heated to 150 to 280 ° C. while reducing the pressure as necessary. The produced water is distilled off to obtain a polyester having a hydroxyl group. The hydroxyl value of the polyester is preferably 5 or more, and the acid value of the polyester is usually 1 to 30, preferably 5 to 20. By giving an acid value, it tends to be negatively charged, and furthermore, when fixing to a recording paper, the affinity between the recording paper and the toner is good and the low-temperature fixability is improved. However, when the acid value exceeds 30, there is a tendency to deteriorate with respect to the stability of charging, particularly environmental fluctuation. The weight average molecular weight is 10,000 to 400,000, preferably 20,000 to 200,000. A weight average molecular weight of less than 10,000 is not preferable because offset resistance deteriorates. On the other hand, if it exceeds 400,000, the low-temperature fixability is deteriorated.

  In addition to the unmodified polyester obtained by the above polycondensation reaction, the polyester preferably contains a urea-modified polyester. The urea-modified polyester is obtained by reacting a terminal carboxyl group or hydroxyl group of the polyester obtained by the above polycondensation reaction with a polyvalent isocyanate compound (PIC) to obtain a polyester prepolymer (A) having an isocyanate group. It is obtained by cross-linking and / or extending the molecular chain by the reaction of the amine with amines. Examples of the polyvalent isocyanate compound (PIC) include aliphatic polyisocyanates (tetramethylene diisocyanate, hexamethylene diisocyanate, 2,6-diisocyanatomethylcaproate, etc.); alicyclic polyisocyanates (isophorone diisocyanate, cyclohexylmethane diisocyanate, etc.) Aromatic diisocyanates (tolylene diisocyanate, diphenylmethane diisocyanate, etc.); araliphatic diisocyanates (α, α, α ′, α′-tetramethylxylylene diisocyanate, etc.); isocyanates; 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 urea-modified polyester is produced by a one-shot method or the like. Polyhydric alcohol (PO) and polyvalent carboxylic acid (PC) are heated to 150-280 ° C. in the presence of a known esterification catalyst such as tetrabutoxytitanate, dibutyltin oxide, etc., and water generated while reducing the pressure as necessary. Distill off to obtain a polyester having a hydroxyl group. Next, at 40 to 140 ° C., this is reacted with polyvalent isocyanate (PIC) to obtain a polyester prepolymer (A) having an isocyanate group. Further, this (A) is reacted with amines (B) at 0 to 140 ° C. to obtain a urea-modified polyester.

When reacting (PIC) and when reacting (A) and (B), a solvent may be used if necessary. Usable solvents include aromatic solvents (toluene, xylene, etc.); ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.); esters (ethyl acetate, etc.); amides (dimethylformamide, dimethylacetamide, etc.) and ethers And those inert to isocyanates (PIC), such as tetrahydrofuran (such as tetrahydrofuran).
In addition, in the crosslinking and / or extension reaction between the polyester prepolymer (A) and the amines (B), a reaction terminator may be used as necessary to adjust the molecular weight of the resulting urea-modified polyester. Examples of the reaction terminator include monoamines (diethylamine, dibutylamine, butylamine, laurylamine, etc.), and those obtained by blocking them (ketimine compounds). The weight average molecular weight of the urea-modified polyester is usually 10,000 or more, preferably 20,000 to 10,000,000, and more preferably 30,000 to 1,000,000. If it is less than 10,000, the hot offset resistance deteriorates. The number average molecular weight of the urea-modified polyester or the like is not particularly limited when the above-mentioned unmodified polyester is used, and may be a number average molecular weight that can be easily obtained to obtain the weight average molecular weight. When the urea-modified polyester is used alone, its number average molecular weight is usually 2000-15000, preferably 2000-10000, more preferably 2000-8000. When it exceeds 20000, the low-temperature fixability and the glossiness when used in a full-color apparatus are deteriorated.

By using the unmodified polyester and the urea-modified polyester in combination, the low-temperature fixability and the gloss when used in the full-color image forming apparatus 100 are improved. Therefore, it is preferable to use the urea-modified polyester alone. The unmodified polyester may include a polyester modified with a chemical bond other than a urea bond. The unmodified polyester and the urea-modified polyester are preferably at least partially compatible with each other in terms of low-temperature fixability and hot offset resistance. Therefore, it is preferable that the unmodified polyester and the urea-modified polyester have a similar composition.
The weight ratio of unmodified polyester to urea-modified polyester is usually 20/80 to 95/5, preferably 70/30 to 95/5, more preferably 75/25 to 95/5, and particularly preferably 80 /. 20-93 / 7. When the weight ratio of the urea-modified polyester is less than 5%, the hot offset resistance is deteriorated, and it is disadvantageous in terms of both heat-resistant storage stability and low-temperature fixability.
The glass transition point (Tg) of the binder resin containing unmodified polyester and urea-modified polyester is usually 45 to 65 ° C, preferably 45 to 60 ° C. If it is less than 45 ° C., the heat resistance of the toner deteriorates, and if it exceeds 65 ° C., the low-temperature fixability becomes insufficient. In addition, since the urea-modified polyester is likely to be present on the surface of the obtained toner base particles, the heat-resistant storage stability tends to be good even when the glass transition point is low as compared with known polyester-based toners.

(Coloring agent)
As the colorant, all known dyes and pigments can be used. For example, carbon black, nigrosine dye, iron black, naphthol yellow S, Hansa yellow (10G, 5G, G), cadmium yellow, yellow iron oxide, ocher , Yellow lead, titanium yellow, polyazo yellow, oil yellow, Hansa yellow (GR, A, RN, R), pigment yellow L, benzidine yellow (G, GR), permanent yellow (NCG), Vulcan fast yellow (5G, R), Tartrazine Lake, Quinoline Yellow Lake, Anthrazan Yellow BGL, Isoindolinone Yellow, Bengala, Red Dan, Lead Zhu, Cadmium Red, Cadmium Mercury Red, Antimon Zhu, Permanent Red 4R, Para Red, Phi Sayred, Parachlor Ortonito Aniline Red, Resol Fast Scarlet G, Brilliant Fast Scarlet, Brilliant Carmine B, Permanent Red (F2R, F4R, FRL, FRLL, F4RH), Fast Scarlet VD, Belkan Fast Rubin B, Brilliant Scarlet G, Resol Rubin GX, Permanent Red F5R , Brilliant Carmine 6B, Pigment Scarlet 3B, Bordeaux 5B, Tolujing Maroon, Permanent Bordeaux F2K, Helio Bordeaux BL, Bordeaux 10B, Bon Maroon Light, Bon Maroon Medium, Eosin Lake, Rhodamine Lake B, Rhodamine Lake Y, Alizarin Lake, Thio Indigo Red B, Thioindigo Maroon, Oil Red, Quinacridone Red, Pyrazolone Red Polyazo Red, Chrome Vermillion, Benzidine Orange, Perinone Orange, Oil Orange, Cobalt Blue, Cerulean Blue, Alkaline Blue Lake, Peacock Blue Lake, Victoria Blue Lake, Metal Free Phthalocyanine Blue, Phthalocyanine Blue, Fast Sky Blue, Indanthrene Blue (RS, BC), indigo, ultramarine blue, bitumen, anthraquinone blue, fast violet B, methyl violet lake, cobalt purple, manganese purple, dioxane violet, anthraquinone violet, chrome green, zinc green, chromium oxide, pyridian, emerald green, pigment Green B, Naphthol Green B, Green Gold, Acid Green Lake, Malachite Green Lake, Lid Russian nin green, anthraquinone green, titanium oxide, zinc white, litbon and mixtures thereof can be used. The content of the colorant is usually 1 to 15% by weight, preferably 3 to 10% by weight, based on the toner.

  The colorant can also be used as a master batch combined with a resin. As a binder resin to be kneaded together with the production of a master batch or a master batch, a polymer of styrene such as polystyrene, poly-p-chlorostyrene, polyvinyl toluene, or a substituted product thereof, or a copolymer of these and a vinyl compound, Polymethyl methacrylate, polybutyl methacrylate, polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, polyester, epoxy resin, epoxy polyol resin, polyurethane, polyamide, polyvinyl butyral, polyacrylic acid resin, rosin, modified rosin, terpene resin, fat Aromatic or alicyclic hydrocarbon resins, aromatic petroleum resins, chlorinated paraffins, paraffin waxes and the like can be mentioned, and these can be used alone or in combination.

(Charge control agent)
Known charge control agents can be used, such as nigrosine dyes, triphenylmethane dyes, chromium-containing metal complex dyes, molybdate chelate pigments, rhodamine dyes, alkoxy amines, quaternary ammonium salts (fluorine-modified 4 Secondary ammonium salts or compounds, tungsten simple substances or compounds, fluorine activators, salicylic acid metal salts, and metal salts of salicylic acid derivatives. Specifically, Bontron 03 of a nigrosine dye, Bontron P-51 of a quaternary ammonium salt, Bontron S-34 of a metal-containing azo dye, E-82 of an oxynaphthoic acid metal complex, E-84 of a salicylic acid metal complex , Phenol-based condensate E-89 (above, manufactured by Orient Chemical Industries), quaternary ammonium salt molybdenum complex TP-302, TP-415 (above, manufactured by Hodogaya Chemical Co., Ltd.)
Quaternary ammonium salt copy charge PSY VP2038, triphenylmethane derivative copy blue PR, quaternary ammonium salt copy charge NEG VP2036, copy charge NX VP434 (above, manufactured by Hoechst), LRA-901, boron complex LR-147 (manufactured by Nippon Carlit), copper phthalocyanine, perylene, quinacridone, azo pigments, and other polymer compounds having functional groups such as sulfonic acid groups, carboxyl groups, and quaternary ammonium salts. Of these, substances that control the negative polarity of the toner are particularly preferably used.
The amount of charge control agent used is determined by the type of binder resin, the presence or absence of additives used as necessary, and the toner production method including the dispersion method, and is not uniquely limited. Preferably, it is used in the range of 0.1 to 10 parts by weight with respect to 100 parts by weight of the binder resin. The range of 0.2 to 5 parts by weight is preferable. When the amount exceeds 10 parts by weight, the chargeability of the toner is too high, the effect of the charge control agent is reduced, the electrostatic attraction with the developing roller is increased, the developer fluidity is lowered, and the image density is lowered. Invite.

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

(External additive)
Inorganic fine particles are preferably used as an external additive for assisting the fluidity, developability and chargeability of the toner particles. The primary particle diameter of the inorganic fine particles is preferably 5 × 10 −3 to 2 μm, and particularly preferably 5 × 10 −3 to 0.5 μm. Moreover, it is preferable that the specific surface area by BET method is 20-500 m <2> / g. The use ratio of the inorganic fine particles is preferably 0.01 to 5 wt% of the toner, and particularly preferably 0.01 to 2.0 wt%.
Specific examples of the inorganic fine particles include, for example, silica, alumina, titanium oxide, barium titanate, magnesium titanate, calcium titanate, strontium titanate, zinc oxide, tin oxide, quartz sand, clay, mica, wollastonite, diatomaceous earth. Examples include soil, chromium oxide, cerium oxide, bengara, antimony trioxide, magnesium oxide, zirconium oxide, barium sulfate, barium carbonate, calcium carbonate, silicon carbide, and silicon nitride. Among these, as the fluidity imparting agent, it is preferable to use hydrophobic silica fine particles and hydrophobic titanium oxide fine particles in combination. In particular, when stirring and mixing are performed using particles having an average particle size of 5 × 10-2 μm or less, the electrostatic force and van der Waals force with the toner are remarkably improved. Even when stirring and mixing inside the developing device is performed, a fluidity-imparting agent is not detached from the toner, a good image quality that does not cause fireflies and the like is obtained, and a reduction in residual toner is further achieved. . Titanium oxide fine particles are excellent in environmental stability and image density stability, but have a tendency to deteriorate the charge rise characteristics. Therefore, if the amount of titanium oxide fine particles added is larger than the amount of silica fine particles added, this side effect is affected. It can be considered large. However, when the added amount of the hydrophobic silica fine particles and the hydrophobic titanium oxide fine particles is in the range of 0.3 to 1.5 wt%, the charge rising characteristics are not greatly impaired, and the desired charge rising characteristics can be obtained, that is, repeated copying. Stable image quality can be obtained even if

Next, a toner manufacturing method will be described. Here, although a preferable manufacturing method is shown, it is not limited to this.
(Toner production method)
(1) A toner material solution is prepared by dispersing a colorant, unmodified polyester, a polyester prepolymer having an isocyanate group, and a release agent in an organic solvent. The organic solvent is preferably volatile with a boiling point of less than 100 ° C. from the viewpoint of easy removal after toner base particle formation. Specifically, toluene, xylene, benzene, carbon tetrachloride, methylene chloride, 1,2-dichloroethane, 1,1,2-trichloroethane, trichloroethylene, chloroform, monochlorobenzene, dichloroethylidene, methyl acetate, ethyl acetate, methyl ethyl ketone, Methyl isobutyl ketone and the like can be used alone or in combination of two or more. In particular, aromatic solvents such as toluene and xylene and halogenated hydrocarbons such as methylene chloride, 1,2-dichloroethane, chloroform, and carbon tetrachloride are 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 Amphoteric surfactants such as nonionic surfactants such as derivatives 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).

In addition, examples of the cationic surfactant include aliphatic quaternary ammonium salts such as aliphatic primary, secondary or secondary amine acids having a fluoroalkyl group, and perfluoroalkyl (C6-C10) sulfonamidopropyltrimethylammonium salts. , Benzalkonium salt, benzethonium chloride, pyridinium salt, imidazolinium salt, trade names include Surflon S-121 (manufactured by Asahi Glass), Florard FC-135 (manufactured by Sumitomo 3M), Unidyne DS-202 (Daikin Industries) Manufactured), MegaFuck F-150, F-824 (Dainippon Ink Co., Ltd.), Xtop EF-132 (Tochem Products), Footgent F-300 (Neos), and the like.
The resin fine particles are added to stabilize the toner base particles formed in the aqueous medium. For this reason, it is preferable to add so that the coverage existing on the surface of the toner base particles is in the range of 10 to 90%. For example, polymethyl methacrylate fine particles 1 μm and 3 μm, polystyrene fine particles 0.5 μm and 2 μm, poly (styrene-acrylonitrile) fine particles 1 μm, trade names are PB-200H (manufactured by Kao), SGP (manufactured by Soken), Techno Examples include polymer SB (manufactured by Sekisui Chemical Co., Ltd.), SGP-3G (manufactured by Sokensha), and micropearl (manufactured by Sekisui Fine Chemical Co., Ltd.). In addition, inorganic compound dispersants such as tricalcium phosphate, calcium carbonate, titanium oxide, colloidal silica, and hydroxyapatite can also be used.

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

The dispersion method is not particularly limited, and known equipment such as a low-speed shear method, a high-speed shear method, a friction method, a high-pressure jet method, and an ultrasonic wave can be applied. Among these, the high-speed shearing method is preferable in order to make the particle size of the dispersion 2 to 20 μm. When a high-speed shearing disperser is used, the rotational speed is not particularly limited, but is usually 1000 to 30000 rpm, preferably 5000 to 20000 rpm. The dispersion time is not particularly limited, but in the case of a batch method, it is usually 0.1 to 5 minutes. The temperature during dispersion is usually 0 to 150 ° C. (under pressure), preferably 40 to 98 ° C.
(3) At the same time as the preparation of the emulsion, the amines (B) are added to cause a reaction with the polyester prepolymer (A) having an isocyanate group. This reaction involves molecular chain crosslinking and / or elongation. The reaction time is selected depending on the reactivity between the isocyanate group structure of the polyester prepolymer (A) and the amines (B), but is usually 10 minutes to 40 hours, preferably 2 to 24 hours. The reaction temperature is generally 0 to 150 ° C, preferably 40 to 98 ° C. Moreover, a well-known catalyst can be used as needed. Specific examples include dibutyltin laurate and dioctyltin laurate.

(4) After completion of the reaction, the organic solvent is removed from the emulsified dispersion (reactant), washed and dried to obtain toner base particles. In order to remove the organic solvent, the temperature of the entire system is gradually raised in a laminar stirring state, and after giving strong stirring in a certain temperature range, the solvent base is removed to produce spindle-shaped toner base particles. . Further, when an acid such as calcium phosphate salt or an alkali-soluble material is used as the dispersion stabilizer, the calcium phosphate salt is dissolved from the toner base particles by a method such as dissolving the calcium phosphate salt with an acid such as hydrochloric acid and washing with water. Remove. It can also be removed by operations such as enzymatic degradation.
(5) A charge control agent is injected into the toner base particles obtained above, and then inorganic fine particles such as silica fine particles and titanium oxide fine particles are externally added to obtain a toner. The injection of the charge control agent and the external addition of the inorganic fine particles are performed by a known method using a mixer or the like. Thereby, a toner having a small particle size and a sharp particle size distribution can be easily obtained. Furthermore, by giving strong agitation in the process of removing the organic solvent, the shape between the true spherical shape and the rugby ball shape can be controlled, and the surface morphology is also controlled between the smooth shape and the umeboshi shape. be able to.
In the above-described embodiment, the toner conveying device using toner powder has been described as the powder conveying device. However, the powder conveying device is not limited to the toner powder, and may be a powder that needs to improve the fluidity of the powder. It can be used effectively.

1 is a cross-sectional view illustrating a schematic configuration of a printer according to an embodiment of the present invention. It is sectional drawing which shows schematic structure of the process cartridge used in FIG. FIG. 2 is a perspective view of a toner bottle used in FIG. 1. It is a perspective view which shows the bottle support part and four toner bottles of the printer used in FIG. FIG. 2 is a perspective view illustrating a part of a toner transport device for Y, M, C, and K in the printer used in FIG. 1. FIG. 2 is a perspective view showing a connection state of a toner cartridge for Y, M, C, and K and a process cartridge in the printer used in FIG. 1. FIG. 3 is an enlarged configuration diagram illustrating a part of a toner conveyance device according to an embodiment of the present invention. FIG. 3 is a schematic diagram illustrating a cross-sectional structure of the toner transport device according to the first embodiment of the present invention. FIG. 6 is a schematic diagram illustrating a cross-sectional structure of a toner conveyance device according to a second embodiment of the present invention. FIG. 10 is a cross-sectional view of a part of the inclined portion of the transport pipe when the transport coil of the toner transport device shown in FIG. 9 is driven to rotate forward. FIG. 10 is a cross-sectional view of a part of the inclined portion of the transport pipe when the transport coil of the toner transport device shown in FIG. 9 is driven in reverse. FIG. 10 is a schematic diagram illustrating a cross-sectional structure of a toner conveyance device according to a third embodiment of the present invention. It is an expanded sectional view of the principal part of FIG. FIG. 10 is a schematic diagram illustrating a cross-sectional structure of a toner conveyance device according to a fourth embodiment of the present invention.

Explanation of symbols

  1Y, 1M, 1C, 1K photoconductor, 5Y, 5M, 5C, 5K developing device, 6Y, 6M, 6C, 6K process cartridge, 7 exposure device, 8 intermediate transfer belt, 9Y, 9M, 9C, 9K primary transfer bias Roller, 12 secondary transfer backup roller, 19 secondary transfer roller, 20 fixing device, 31 bottle container, 32Y, 32M, 32C, 32K toner cartridge, 33Y bottle body, 34Y resin case, 35Y handle, 36Y shutter, 40Y, 40M, 40C, 40K toner conveying device, 41Y driving motor, 42Y driving gear group, 43Y toner conveying pipe, 43Ya opening, 43Yb horizontal portion, 43Yd inclined portion, 43Ye inner space, 44Y toner receiving portion, 51Y developing sleeve, 52Y doctor, 53Y developer container, 54 Toner accommodating portion, 55Y toner conveying screw, 56Y density sensor, 70Y conveying coil, 71Y rotating shaft, 71Ya tip, 71Yb regulating unit, 73Y space restricting member

Claims (11)

A powder container for storing powder, a powder transport pipe for guiding the powder from the powder container to a transport destination below the powder container, and a rotational motion stored in the powder transport pipe A powder conveying member that moves the powder by applying a moving force to the powder in the conveying direction, a driving unit that rotates the powder conveying member, and a control that controls the driving unit A powder conveying device that delivers the powder in the powder container through the powder conveying tube to the conveying destination,
The powder conveying apparatus characterized in that the driving means is freely rotatable forward and reverse, and the control unit conveys the powder to the upstream side in the conveying direction by driving the driving means in reverse at a predetermined timing. In the powder conveying apparatus according to claim 1,
A powder conveying apparatus, wherein a space regulating member for reducing the internal space volume is disposed in at least a part of the internal space of the powder conveying tube via the powder conveying member. In the powder conveying apparatus according to claim 1 or 2,
The powder conveying apparatus, wherein the powder conveying member is a resin coil. In the powder conveying apparatus according to any one of claims 1 to 3,
The powder conveying apparatus, wherein the powder is toner used in an image forming apparatus. In the powder conveying apparatus according to claim 4,
The powder conveying apparatus according to claim 1, wherein the toner is a toner having an accelerated aggregation degree of 40% or less. In the powder conveying apparatus according to claim 4 or 5,
The toner is a toner having an average circularity of 0.90 or more. The powder conveying apparatus according to any one of claims 4 to 6,
The toner has a volume average particle diameter of 3 to 8 μm and a ratio (Dv / Dn) of the volume average particle diameter (Dv) to the number average particle diameter (Dn) in the range of 1.00 to 1.40. A powder conveyance device characterized by the above. In the powder conveying apparatus according to any one of claims 4 to 7,
In the toner, a toner material liquid in which at least a polyester prepolymer having a functional group containing a nitrogen atom, polyester, a colorant, and a release agent is dispersed in an organic solvent is crosslinked and / or extended in an aqueous medium. A powder transporting device, characterized by being a toner containing a toner obtained by heating. An image carrier that carries an electrostatic latent image and a developer containing at least toner are accommodated, and the toner in the developer is supplied to the electrostatic latent image of the image carrier to form the electrostatic latent image. In a process cartridge integrally configured with a developing device that forms a toner image,
The process cartridge includes a powder transport device that transports the toner from a toner storage container that stores the toner to the developing device,
9. The process cartridge according to claim 5, wherein the powder conveying device is the powder conveying device according to any one of claims 5 to 8. An image carrier that carries an electrostatic latent image and a developer containing at least toner are accommodated, and the toner in the developer is supplied to the electrostatic latent image of the image carrier to form the electrostatic latent image. An image forming apparatus comprising: a developing device that forms a toner image; and a powder conveying device that conveys the toner from a toner container that contains the toner to the developing device.
The image forming apparatus according to claim 5, wherein the powder conveying device is the powder conveying device according to claim 5. The image forming apparatus according to claim 10.
The image forming apparatus, wherein the image carrier and the developing device are a process cartridge integrally formed.

Images