JP6468926B2 - Development method and image forming method - Google Patents

Description

  The present invention relates to an electrophotographic image forming apparatus using a process cartridge. In particular, it is suitable for application to a color electrophotographic image forming apparatus.

  2. Description of the Related Art Conventionally, in an image forming apparatus using an electrophotographic image forming process, a cartridge system in which a cartridge such as a developing cartridge or a process cartridge is detachable from an image forming apparatus main body has been adopted. In such a cartridge system, a function of displaying the remaining printable number of sheets may be added so that the user can replace the cartridge at an appropriate timing. In order to add such a function, it is necessary to detect or predict the remaining amount of toner in the cartridge, and various methods have been proposed so far.

  Among them, a light-emitting element such as an LED attached to the image forming apparatus main body and the like and a light-receiving element such as a phototransistor form an optical path that passes through the toner chamber, and the remaining amount of toner from the time when the toner blocks the optical path A light transmission type toner remaining amount detecting method for detecting the toner is widely used. (Patent Document 1).

In the light transmission type toner remaining amount detecting method, there is a method in which a light emitting side light guide member and a light receiving side light guide member are provided in the toner containing unit as means for guiding detection light into the toner containing chamber. The light emitting side light guide member guides detection light emitted from a light emitting element such as an LED to the inside of the toner containing chamber. The light-receiving side light guide member guides the detection light that has passed through the toner containing chamber to a light receiving element such as a phototransistor outside the toner containing chamber. (Patent Document 2)
Furthermore, a method has also been proposed in which a light guide member in which a light-emitting side light guide member and a light-receiving side light guide member are integrated is disposed in the longitudinal central region of the toner storage chamber. (Patent Document 3).

  The developing device also contains a developing carrier for supplying toner to the photosensitive drum, a developing chamber provided with a toner supply member for supplying toner to the developing carrier, and toner supplied to the developing chamber. A toner storage chamber. Further, the toner storage chamber may be located below the developing chamber in the direction of gravity, and it may be necessary to supply toner against gravity.

  As a method for transporting toner from the toner storage chamber to a developing chamber disposed above, a method of attaching a flexible sheet member to a stirring member that stirs the toner in the toner storage chamber by a rotating operation has been proposed. In this proposal, as the sheet member rotates, the sheet member has a deformation position for elastically deforming the sheet member and a restoration position for releasing the elastic deformation of the sheet member, and when the sheet member transitions from the deformed state to the restored state. The toner is transported by the generated force. (Patent Document 4)

JP 2001-318524 A JP 2003-131479 A JP 2003-167490 A JP 2011-253203 A

  However, in the conventional invention, the boundary between the deformation position and the restoration position of the sheet member for conveying the toner is provided above the horizontal line passing through the rotation center of the toner conveyance member.

  In this case, in a state where the sheet member is deformed, the toner on the sheet member spills down, and the amount of toner that can be held on the sheet decreases. When the amount of toner that can be held on the sheet is small, the amount of toner that can be conveyed to the developing chamber is reduced, and the amount of toner conveyed to the toner supply member is reduced, which may affect the image.

  In the conventional invention, for the purpose of reducing the size of the cartridge, a configuration in which the light guide member is provided on the upstream side in the sheet member rotation direction from the boundary between the deformation position and the restoration position of the sheet member is used. In this configuration, the light guide member has a convex portion protruding from the side wall of the toner container. Also in this case, when the sheet member passes the convex portion of the light guide member, the amount of toner on the sheet member for spilling and transporting to the developing chamber is reduced, and the deformation position and the restoration position of the sheet member are reduced. The toner on the sheet member is lost before passing through the boundary portion. In the future, in order to achieve further miniaturization of the cartridge, a configuration in which the light guide member protrudes further into the toner container is being studied.

  The present invention is a further development of the prior art. The following problems occur when the cartridge in the conventional invention is further reduced in size.

  In order to further reduce the size of the cartridge, the present inventors have worked on a configuration in which the function of the boundary between the deformation position and the restoration position of the sheet member described above is satisfied by the light guide member. However, since the light guide member is disposed only in the central portion in the longitudinal direction of the toner storage chamber, the deformation / restoration of the sheet member occurs only in the vicinity of the longitudinal center. For this reason, the regions at both longitudinal ends of the toner storage chamber are not deformed or restored, and the ability to convey toner is weakened. As a result, the amount of toner transported to the developing chamber is large at the longitudinal central portion and is reduced at both longitudinal end portions. Also, if the developer container is left for a long period of time, the toner is compacted and the fluidity is lowered, and as a result, the toner conveying ability at both ends in the longitudinal direction when driven again becomes weaker than that during continuous printing. End up. In particular, when left in a low temperature and low humidity environment for a long time, the decrease in fluidity becomes more remarkable.

  If the amount of toner in the developing chamber is not uniform in the longitudinal direction, the density of the printed image tends to be uneven in the longitudinal direction.

  The above object is achieved by the present invention described below.

That is, a developing method for developing an electrostatic latent image on an image carrier with toner using a developing device,
The developing device includes:
Toner and
A development chamber,
A toner storage chamber for storing the toner , which is disposed vertically below the developing chamber ;
A toner conveying member that is provided inside the toner accommodating chamber and conveys the toner against the gravity from the toner accommodating chamber to the developing chamber ;
Is provided inside the front Symbol toner chamber, and the light guide member for the toner amount detection,
Have
The toner conveying member is
An agitation shaft that can be rotated by an external driving force;
A sheet member attached to the agitation shaft and rotating together with the agitation shaft;
Have
Wherein the light guide member, Ri Contact the said sheet member with the rotation of the sheet member is first protrusion to elastically deform is formed,
The inside of the toner chamber, with reference to the position of the light guide member, along said longitudinal direction of the toner chamber, is provided with convex member projecting from the inner wall surface of the toner accommodating chamber,
The convex member is formed with a second convex portion,
In any cross-section in a direction orthogonal to a longitudinal direction of said toner accommodating chamber, and a cross-section first protrusion before SL becomes the maximum, when the second convex portion is overlapped with the cross section becomes maximum, two In the cross section, the shape of the first convex portion and the second convex portion overlap,
Using the restoring force that the sheet member restores when the sheet member passes through the first and second protrusions, the toner on the sheet member is removed from the toner storage chamber to the developing chamber. Transported to
The toner has toner particles containing a binder resin , a colorant, and a release agent,
The toner is, the following relation (1) and (2) you satisfied 300 (mJ) ≦ E ≦ 450 (mJ) (1)
1.00 ≦ Ec / E ≦ 2.50 (2)
(E in the above formulas (1) and (2) is perpendicular to the toner powder layer in the container while rotating the peripheral speed of the outermost edge of the propeller blade at 100 mm / s in the powder flowability analyzer. It represents the sum of the rotational torque and the vertical load obtained when the measurement is started from the position of 100 mm from the bottom surface of the powder layer and entered to the position of 10 mm from the bottom surface. Ec represents the sum of the rotational torque and the vertical load measured in the manner of measuring E in the toner powder layer to which a load of 3 kPa is applied.)
The developing method is characterized by the above.

  According to the present invention, the toner can be uniformly conveyed to the developing chamber in the longitudinal direction even when the developing container is left for a long period of time and the toner is compacted while reducing the size of the developing device and the process cartridge. An image having a uniform direction density and excellent gradation reproducibility can be obtained.

FIG. 4 is a perspective view illustrating details of a toner conveyance function according to an exemplary embodiment. 1 is a diagram illustrating a configuration of an electrophotographic image forming apparatus equipped with a process cartridge according to an embodiment. FIG. It is a figure explaining the process cartridge which concerns on an Example. FIG. 6 is a diagram illustrating a developing unit according to an embodiment. FIG. 6 is a diagram illustrating a toner stirring operation according to an example. It is a figure explaining the developing device frame which concerns on an Example. It is a figure explaining the 1st image development frame and light guide member which concern on an Example. It is a figure explaining the 1st image development frame and light guide member which concern on an Example. FIG. 6 is a view of a remaining amount detection unit according to the embodiment as viewed from the outside of the toner storage chamber. FIG. 6 is a view of the remaining amount detection unit according to the embodiment when viewed from the inside of the toner storage chamber. FIG. 4 is a perspective view illustrating details of a toner conveyance function according to an exemplary embodiment. It is explanatory drawing of the external appearance (a) of the propeller-type blade of a powder fluidity | liquidity analyzer, and the twist angle (b) of a blade outermost edge part.

  Hereinafter, a development cartridge, a process cartridge to which an image forming method can be applied, and an image forming apparatus will be described with reference to the drawings.

1. Overall Configuration of Image Forming Apparatus First, the overall configuration of an electrophotographic image forming apparatus (hereinafter referred to as an image forming apparatus) 100 will be described with reference to FIG. As shown in FIG. 2, four detachable process cartridges 70 (70a, 70b, 70c, 70d) are mounted by mounting members (not shown). Further, the upstream side in the mounting direction of the image forming apparatus 100 of the process cartridge 70 is defined as the front side surface, and the downstream side in the mounting direction is defined as the back side surface side. In FIG. 2, the process cartridge 70 is provided in the apparatus main body 100 so as to be inclined with respect to the horizontal direction.

  Each process cartridge 70 includes a developing device of the present invention, and includes an image carrier (electrophotographic photosensitive drum (hereinafter referred to as a photosensitive drum)) 1 (1a, 1b, 1c, 1d), and a photosensitive drum. 1 includes process means such as a charging roller 2 (2a, 2b, 2c, 2d), a developing roller 25 (25a, 25b, 25c, 25d), and a cleaning member 6 (6a, 6b, 6c, 6d). Are arranged. The charging roller 2 uniformly charges the surface of the photosensitive drum 1, and the developing roller 25 develops a latent image formed on the photosensitive drum 1 (on the image carrier) with toner and makes it visible. It is to be imaged. The cleaning member 6 removes the toner remaining on the photosensitive drum 1 after the toner image formed on the photosensitive drum 1 is transferred onto the recording medium (on the transfer material).

  A scanner unit 3 for selectively exposing the photosensitive drum 1 based on image information and forming a latent image on the photosensitive drum 1 is provided below the process cartridge 70.

  A cassette 17 containing a recording medium S is attached to the lower part of the apparatus main body 100. A recording medium transport unit is provided so that the recording medium S is transported above the apparatus main body 100 through the secondary transfer roller 69 and the fixing unit 74. That is, the feeding roller 54 for separating and feeding the recording medium S in the cassette 17 one by one, the conveying roller pair 76 for feeding the fed recording medium S, and the latent image and the recording medium formed on the photosensitive drum 1. A registration roller pair 55 for synchronizing with S is provided. Further, an intermediate transfer unit serving as an intermediate transfer unit for transferring a toner image formed on each photosensitive drum 1 (1a, 1b, 1c, 1d) above the process cartridge 70 (70a, 70b, 70c, 70d). A unit 5 is provided. The intermediate transfer unit 5 includes a driving roller 56, a driven roller 57, a primary transfer roller 58 (58a, 58b, 58c, 58d) at a position facing the photosensitive drum 1 of each color, and a position facing the secondary transfer roller 69. A transfer belt 9 that has an opposing roller 59 and is an intermediate transfer member is stretched over the belt. The transfer belt 9 circulates and moves so as to face and be in contact with all the photosensitive drums 1 and applies a voltage to the primary transfer rollers 58 (58a, 58b, 58c, 58d), whereby the photosensitive drum 1 To primary transfer onto the transfer belt 9. The toner on the transfer belt 9 is transferred to the recording medium S by applying a voltage to the opposing roller 59 and the secondary transfer roller 69 disposed in the transfer belt 9. Although the configuration having the intermediate transfer member has been described, an apparatus configuration that does not use the intermediate transfer member may be used.

  When forming an image, each photosensitive drum 1 is rotated, and the photosensitive drum 1 uniformly charged by the charging roller 2 is selectively exposed from the scanner unit 3. Thereby, an electrostatic latent image is formed on the photosensitive drum 1. The latent image is developed by the developing roller 25. As a result, each color toner image is formed on each photosensitive drum 1. In synchronization with this image formation, the registration roller pair 55 conveys the recording medium S to the secondary transfer position where the opposing roller 59 and the secondary transfer roller 69 are in contact with each other with the transfer belt 9 interposed therebetween. Then, by applying a transfer bias voltage to the secondary transfer roller 69, each color toner image on the transfer belt is secondarily transferred to the recording medium S (transfer material). As a result, a color image is formed on the recording medium S. The recording medium S on which the color image is formed is heated and pressed by the fixing unit 74 in the fixing step, and the toner image is fixed. Thereafter, the recording medium S is discharged to the discharge unit 75 by the discharge roller 72. The fixing unit 74 is disposed on the upper part of the apparatus main body 100.

2. Process Cartridge Next, a process cartridge 70 having the developing device of the present invention will be described with reference to FIG. FIG. 3 is a main cross section of a process cartridge 70 containing toner. The cartridge 70a containing yellow toner, the cartridge 70b containing magenta toner, the cartridge 70c containing cyan toner, and the cartridge 70d containing black toner have the same configuration.

  The process cartridge 70 (70a, 70b, 70c, 70d) has a cleaning unit 26 (26a, 26b, 26c, 26d) and a developing unit 4 (4a, 4b, 4c, 4d). The cleaning unit 26 includes a photosensitive drum 1 (1a, 1b, 1c, 1d), a charging roller 2 (2a, 2b, 2c, 2d), and a cleaning member 6 (6a, 6b, 6c, 6d). . The developing unit 4 includes a developing roller 25.

  As described above, the charging roller 2 and the cleaning member 6 are disposed on the circumference of the photosensitive drum 1. The cleaning member 6 includes an elastic member 7 formed of a rubber blade and a cleaning support member 8. The tip 7 a of the rubber blade 7 is disposed in contact with the rotation direction of the photosensitive drum 1 in the counter direction. The residual toner removed from the surface of the photosensitive drum 1 by the cleaning member 6 falls into the removed toner chamber 27a. In addition, a squeeze sheet 21 that prevents the removed toner in the removed toner chamber 27 a from leaking is in contact with the photosensitive drum 1. Then, by transmitting the driving force of a main body driving motor (not shown) as a driving source to the cleaning unit 26, the photosensitive drum 1 is rotationally driven according to the image forming operation. The charging roller 2 is rotatably attached to the cleaning unit 26 via the charging roller bearing 28, and is pressurized toward the photosensitive drum 1 by the charging roller pressing member 46 and is rotated following the photosensitive drum 1. .

3. Developing Unit and Toner Conveying Unit As shown in FIG. 3, the developing unit 4 (developing device) includes a developing roller 25 that rotates in the direction of arrow B in contact with the photosensitive drum 1, and a developing frame that supports the developing roller 25. 31. The developing roller 25 is rotatably supported by the developing frame 31 via a pre-development bearing 12 and a developing rear bearing 13 that are respectively attached to both sides of the developing frame 31 (see FIG. 3). A toner supply roller 34 that rotates in the direction of arrow C in contact with the developing roller 25 and a developing blade 35 for regulating the toner layer on the developing roller 25 are disposed on the circumference of the developing roller 25. Further, a blowout prevention sheet 20 as a development contact sheet for preventing the toner from leaking from the development frame body 31 in contact with the development roller 25 is disposed. Further, the toner storage chamber 31 a of the developing frame 31 is provided with a toner transport member 36 that is a transport member for stirring the stored toner and transporting the toner to the toner supply roller 34.

  As shown in FIG. 4, the toner conveying member 36 includes a stirring shaft 36a that can be rotated by an external driving force, and a sheet member 36b that is attached to the stirring shaft 36a and rotates together with the stirring shaft 36a. . Further, a remaining amount detection means 140 for detecting the remaining amount of toner in the toner storage chamber 31a is provided on the side wall inside the toner storage chamber 31a.

  Next, toner conveyance of the developing unit will be described. As shown in FIG. 4, when the toner conveying member 36 rotates (in the direction of arrow H), the toner 200 is pushed and moved by the sheet member 36b. When the toner conveying member 36 further rotates, the toner is lifted by the sheet member 36b, and the toner is conveyed to the toner supply roller 34 disposed in the developing chamber as shown in FIG. At that time, a part of the toner falls into the toner storage chamber 31a, accumulates at the bottom of the toner storage chamber 31a, and returns to its original state. By repeating this cycle, the toner is agitated and conveyed.

  The toner supplied to the toner supply roller 34 in the developing chamber is used for developing the latent image on the photosensitive drum 1 by the developing means as described above.

4). Next, the configuration of toner remaining amount detection provided in the toner storage chamber 31a will be described with reference to FIGS.

First, the light guide member 141 (toner amount detection light guide member) constituting the remaining amount detection means 140 shown in FIG. 5 will be described.
Here, as shown in FIG. 6, the developing frame 31 is formed by joining the first developing frame 131 and the second developing frame 132 by ultrasonic welding or the like, and the light guide member 141 is used for the first development. It is attached to the frame 131. 7 and 8 are views in which the first developing frame 131 and the light guide member 141 are integrated, and are respectively shown from the front and back directions. 9 and 10 show the details thereof.

  First, as shown in FIG. 9, the light guide member 141 includes a light emitting side light guide 141a for guiding the detection light 152 emitted from the light emitting element 150 outside the process cartridge into the toner storage chamber 31a, A light receiving side light guide 141b that guides the detection light 152 that has passed through the toner storage chamber 31a to the light receiving element 151 is integrally formed. The light-emitting side light guide 141a uses the detection light 152 emitted from the light-emitting element 150 as an incident portion 141c where the detection light 152 is incident on the light-emitting side light guide 141a and the detection light 152 incident on the light-emitting side light guide 141a as a toner. It has a light emission side window 141d that exits into the storage chamber 30 (FIG. 10). In general, the light emitted from the light emitting element 150 is often diffused light, and the incident portion 141c has a convex lens shape in order to correct the light in the same direction. The lens shape is designed in consideration of the distance between the light emitting element 150 and the incident portion 141c. Similarly, the light receiving side light guide 141b includes a light receiving side window 141e (FIG. 10) through which the detection light 152 having passed through the toner storage chamber 30 enters the light receiving side light guide 141b, and the light receiving side light guide. It has the output part 141f which radiate | emits the detection light 152 which injected into 141b toward the light receiving element 151. FIG. As shown in FIG. 10, the light emitting side window 141d and the light receiving side window 141e are arranged to face each other, and a spatial light path 153 through which the detection light 152 passes is formed between them.

  Thereafter, detection light 152 is emitted from the emitting portion 141f toward the light receiving element 151 and is received by the light receiving element 151, whereby it is detected that the light has passed through the toner storage chamber 31a. The method for detecting the remaining amount of toner in the toner storage chamber 31a is to detect the detection light 152 passing through the spatial light path 153 during one period when the toner conveying member 36 agitates the toner in the toner storage chamber 31a. The amount of toner blocking is measured to predict the remaining amount of toner.

5. Toner Transport Using Light Guide Member Next, a toner transport configuration in the developing unit 4 of the process cartridge 70 in this embodiment will be described.

  In this embodiment, the terms indicating the direction of up, down, vertical, and horizontal in the configuration and operation of the developing unit or process cartridge are those in their normal use unless otherwise specified. Represents the direction. That is, the normal use state of the developing unit or the process cartridge is a state in which the image forming apparatus body is properly mounted and the image forming operation is performed.

  4 and 5 are schematic cross-sectional views of the process cartridge 70 for explaining the toner conveyance state.

  As shown in FIG. 4, the developing unit 4 includes a developing chamber 31b and a toner storage chamber 31a. In the developing chamber 31b, a developing roller 25, a toner supply roller 34, a developing blade 35, and the like are accommodated. In the toner storage chamber 31a, the toner 200 supplied to the developing chamber 31b is stored, and a toner conveying member 36 for supplying toner to the developing chamber 31b is provided. The toner storage chamber 31a is disposed vertically below the developing chamber 31b. Therefore, it is necessary to convey the toner against the gravity from the toner storage chamber 31a to the developing chamber 31b. Further, an opening 31c through which the toner passes is provided between the developing chamber 31b and the toner storage chamber 31a, and the opening 31c is provided above the toner storage chamber 31a.

  Further, as shown in FIG. 4, a remaining amount detection means 140 for detecting the remaining amount of toner is provided on the side wall of the toner storage chamber 31a. In the toner storage chamber 31a, the toner is stored in the developing chamber 31b. A toner conveying member 36 having elasticity for supplying the toner is rotatably provided.

  The toner conveying member 36 is elastic and includes a stirring shaft 36a that can be rotated by an external driving force, and a sheet member 36b that is attached to the stirring shaft 36a and rotates together with the stirring shaft 36a.

  The sheet member 36b can be preferably manufactured using a flexible resin sheet such as a polyester film, a polyphenylene sulfide film, or a polycarbonate film. The thickness of the sheet member 36b is preferably 50 μm to 250 μm.

  As shown in FIG. 4, as a configuration for transporting toner from the toner storage chamber 31a to the developing chamber 31b, the sheet member 36b is used for the light emitting side window 141d and the light receiving side window 141e of the light guide member 141 for detecting the remaining amount of toner (FIG. 8). Contact) and elastically deform. As the toner conveying member 36 rotates, the sheet member 36b comes into contact with the light emitting side window 141d and the light receiving side window 141e, so that the sheet member 36b is deformed by receiving a force from both side windows (141d, 141e). Next, when the sheet member 36b passes through the both side windows (141d, 141e), the toner is conveyed to the developing chamber 31b by using the restoring force restored by the sheet member 36b.

  However, the region where the sheet member 36b is elastically deformed and then restored is only at both side window portions (141d, 141e) of the light guide member 141 provided at the longitudinal center of the first developing frame 131 as shown in FIG. is there. On the other hand, since the sheet member 36b is not deformed / restored in the region other than the longitudinal center portion of the developing frame 31, the amount of toner conveyed to the developing chamber is smaller in the longitudinal end region than in the longitudinal center region. Further, when the developing container is left for a long period of time, the toner is compacted and the fluidity is deteriorated, and the toner conveying ability at both ends in the longitudinal direction when driven again becomes weaker than that during continuous printing.

  Therefore, in the present invention, as shown in FIG. 1, the position of the light guide member is taken as a reference, and the distance from the light guide member is along the longitudinal direction of the toner storage chamber (first developing frame 131). Convex members (131 d, 131 e) having the same shape as the light emitting side window 141 d and the light receiving side window 141 e of the light guide member 141 are provided at the position (longitudinal end side of the first developing frame 131).

  “In an arbitrary cross section in the direction orthogonal to the longitudinal direction of the toner storage chamber, the cross section where the convex portion formed by the light guide member is maximized and the cross section where the convex portion formed by the convex member is maximum overlap. "When the shape of the convex part protruding from the wall surface overlaps in two cross sections" means that both convex parts (1) and (2) below have substantially the same shape. . Note that having substantially the same shape is also referred to as “having an equivalent shape”.

  (1) As shown in FIG. 5, the light guide member side windows (141d, 141e) protrude from the side wall of the developing device frame 31. The convex portion 141t (the container shape in the portion where the light guide member and the convex member are not provided ( (Shown by a two-dot broken line) and a portion protruding inward from the container).

  (2) A convex portion formed by a convex member protruding from the side wall of the developing device frame 31.

  By providing such a convex portion, the restoring force of the sheet due to the deformation / restoring operation of the sheet member 36b can be generated even at the longitudinal end portion, and the toner can be conveyed to the developing chamber 31b uniformly in the longitudinal direction.

  As another embodiment, as shown in FIG. 11, a convex portion having the same shape as the light emitting side window 141d and the light receiving side window 141e of the light guide member 141 is formed in a region where the light guide member 141 of the first developing frame 131 is not present. The shaped members (131f, 131g) may be arranged in a rib shape (rib shaped member).

  With the image forming apparatus described above, it is possible to efficiently and uniformly transport toner from the toner storage chamber to the developing chamber with a simple and easy-to-support structure.

6). Toner The toner has toner particles containing a binder resin, a colorant, and a release agent, and the toner satisfies the following relational expressions (1) and (2).
300 (mJ) ≦ E ≦ 450 (mJ) (1)
1.00 ≦ Ec / E ≦ 2.50 (2)
(E in the above formulas (1) and (2) is perpendicular to the toner powder layer in the container while rotating the peripheral speed of the outermost edge of the propeller blade at 100 mm / s in the powder flowability analyzer. It represents the sum of the rotational torque and the vertical load obtained when the measurement is started from the position of 100 mm from the bottom surface of the powder layer and entered to the position of 10 mm from the bottom surface. Ec represents the sum of the rotational torque and the vertical load measured in the manner of measuring E in the toner powder layer given a load of 3 kPa.)
By combining such toner with the above-described image forming apparatus, even when the developer container is left for a long period of time and the fluidity of the toner is lowered, the toner is efficiently and uniformly transported from the toner storage chamber to the developing chamber. It becomes possible.

  The smaller the value of E, the better the fluidity of the toner, the better the toner supply from the toner storage chamber to the developing chamber, and the excellent density uniformity in the longitudinal direction. If E is less than 300, the fluidity is too good and toner scattering tends to occur. When E exceeds 450, it becomes difficult to supply the toner stably, and even in the continuous printing in which the toner is sufficiently loosened, the density is not favorable. Ec / E indicates the ratio of the total energy of the powder layer in which a load is applied to the toner and the normal toner powder layer, and indicates the degree of change in fluidity with respect to pressure. A toner having Ec / E close to 1 exhibits a characteristic that it is easily unpacked or difficult to pack even if the toner is packed, and the change in toner fluidity is small even when the developing container is left for a long period of time.

  The method of controlling the values of E and Ec in the present invention includes a method of controlling by selecting the kind of inorganic fine particles added to the toner particles, adjusting the prescription, adding amount, and adding conditions.

  As a more preferable control method, a method of adding silica fine particles having a small primary particle number number average particle size of 4 to 16 nm, or titanium oxide fine particles having a primary particle number average particle size of 50 nm or less is added. The adjusting method is preferred.

  The silica fine particles and the titanium oxide fine particles are preferably those that have been treated with at least silicone oil. The lubricant effect of the silicone oil makes it difficult for the toner to be compacted or it is easy to loosen even if it is compacted, and the value of Ec / E can be kept low. The treatment amount of the silicone oil at that time is preferably 5 to 40 parts by mass with respect to 100 parts by mass of silica fine particles and titanium oxide fine particles.

  In addition, the toner may contain a small amount of silica fine particles having a primary particle number average diameter of 20 nm to 300 nm for the purpose of preventing the silica fine particles from being embedded in the toner surface.

  Examples of the silicone oil used include straight silicone oil such as dimethyl silicone oil, methylphenyl silicone oil, and methylhydrogen silicone oil, epoxy-modified silicone oil, carboxyl-modified silicone oil, carbinol-modified silicone oil, methacryl-modified silicone oil, and mercapto-modified silicone. Oil, phenol-modified silicone oil, one-end reactive modified silicone oil, heterogeneous functional group-modified silicone oil, polyether-modified silicone oil, methylstyryl-modified silicone oil, alkyl-modified silicone oil, higher fatty acid ester-modified silicone oil, hydrophilic special modification Silicone oil, higher alkoxy-modified silicone oil, higher fatty acid-containing modified silicone oil It can be used Le, a modified silicone oil such as fluorine-modified silicone oil. Moreover, you may mix 2 or more types among the said silicone oil according to a use. Also particularly preferred here is dimethyl silicone oil. The reason for this is not clear, but it is expected to be excellent in charging stability because of its simple structure.

  The silica fine particles and titanium oxide fine particles may be further treated with a coupling agent such as a silane compound, a titanate coupling agent, an aluminum coupling agent, or a zircoaluminate coupling agent in order to further increase the degree of hydrophobicity. Specifically, for example, hexamethyldisilazane, vinyltrimethoxysilane, vinyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, isobutyltrimethoxysilane, dimethyldimethoxysilane, Examples thereof include dimethyldiethoxysilane, trimethylmethoxysilane, hydroxypropyltrimethoxysilane, phenyltrimethoxysilane, n-hexadecyltrimethoxysilane, and n-octadecyltrimethoxysilane.

  More preferably, the surface treated with both the coupling agent and the silicone oil can be reliably hydrophobicized. The order of the treatment is not limited, but the treatment with silicone oil and the coupling treatment can reduce oil release and is more preferable.

  By adding inorganic fine particles of 80 nm or more and 800 nm or less in addition to silica fine particles and titanium oxide fine particles, the toner can be expected to further stabilize environmental characteristics and durability characteristics. Specifically, hydrotalcite, aluminum oxide, zinc oxide fine powder and the like can be suitably used because the charge amount can be easily controlled over a long period of time. However, it is necessary to suppress these fine powders to be used to the extent that the flow characteristics of the silica fine particles and titanium oxide fine particles are not impaired.

  The mixer for uniformly adhering these additives to the toner surface is not particularly limited as long as it can achieve the characteristics, and a known production method can be used. As an example, there are existing high-speed stirring type mixers such as a Henschel mixer and a super mixer.

<Measuring method of E (mJ) and Ec (mJ)>
E (mJ) and Ec (mJ) in the present invention are measured by using “powder fluidity analyzer powder rheometer FT4” (manufactured by Freeman Technology, hereinafter may be abbreviated as FT4).

  Specifically, the measurement is performed by the following operation.

  In all operations, a 48 mm-diameter blade dedicated to FT4 (see FIG. 3; model number: C210, material: SUS, hereinafter may be abbreviated as blade) is used as the propeller blade. This propeller-type blade has a rotation axis in the normal direction at the center of a 48 mm × 10 mm blade plate, and the blade plate has an outermost edge portion (24 mm portion from the rotation shaft) of 70 ° and a portion 12 mm from the rotation shaft. It is smoothly twisted counterclockwise, such as 35 °.

  As the measurement container, a cylindrical split container dedicated to FT4 (model number: C203, material: glass, diameter 50 mm, volume 160 ml, height 82 mm from the bottom surface to the split part, hereinafter may be abbreviated as container) is used. .

  Incidentally, 100 g of toner left in an environment of a temperature of 23 ° C. and a humidity of 60% RH for 3 days or more is put in the measurement container to form a toner powder layer.

(1) Conditioning operation (a) A propeller blade is rotated clockwise with respect to the powder layer surface so that the peripheral speed of the outermost edge of the blade is 60 mm / sec (the powder layer is loosened by the rotation of the blade). Direction). The surface of the powder layer at an approach speed at which the angle between the locus drawn by the outermost edge of the moving blade and the surface of the powder layer (hereinafter sometimes referred to as the angle formed) is 5 °. From the bottom surface of the toner powder layer to the position of 10 mm in the vertical direction. Thereafter, the toner powder layer is rotated while rotating clockwise with respect to the surface of the powder layer so that the peripheral speed of the outermost edge of the blade is 60 mm / sec. The blade is advanced to a position of 1 mm from the bottom surface. Further, while rotating clockwise with respect to the powder layer surface so that the angle formed is 5 ° and the peripheral speed of the outermost edge of the blade is 60 mm / sec, 100 mm from the bottom surface of the toner powder layer. Move the blade to position and remove it. When the extraction is completed, the toner attached to the blade is wiped off by rotating the blade alternately in small clockwise and counterclockwise directions.

  (B) The operations (1) to (a) are repeated five times to remove the air taken in the toner powder layer.

(2) Compression operation When measuring Ec (mJ), the toner powder layer subjected to the conditioning operation in (1) is compressed by applying a pressure of 3 kPa. Specifically, a compression test piston (diameter 48 mm, height 20 mm, lower mesh tension) is mounted instead of the propeller blade. The piston is lowered at 0.1 mm / s to compress the toner. When the load on the piston reaches 3 kPa, the descent is stopped and held for 60 seconds to form a compressed powder layer.

(3) Split operation The conditioned powder layer or compressed powder layer is cut off at the split portion of the FT4 container described above, and the toner on the upper part of the powder layer is removed. By this operation, the volume of the toner powder layer can be made the same for each measurement.

(4) Measurement operation (i) Measurement of E (a) The same conditioning operation as (1)-(a) is performed once.

  (B) Rotate the propeller blade counterclockwise with respect to the powder layer surface (direction in which the powder layer is pushed in by rotation of the blade) so that the peripheral speed of the outermost edge of the blade is 100 mm / sec. To do. The blade is advanced in the vertical direction from the powder layer surface to a position 10 mm from the bottom surface of the toner powder layer at an approach speed of 5 °. Thereafter, the blade rotates clockwise with respect to the surface of the powder layer so that the peripheral speed of the outermost edge of the blade is 60 mm / sec, and the angle forming the vertical entry speed to the powder layer becomes 2 °. It is made to approach to the position of 1 mm from the bottom face of the powder layer at the approach speed. Further, the blade is moved to a position of 100 mm from the bottom surface of the powder layer at a speed of 5 °, and is extracted. When the extraction is completed, the toner attached to the blade is wiped off by rotating the blade alternately in small clockwise and counterclockwise directions.

  (C) The operations of (4)-(i)-(b) are further repeated 6 times, and the rotation obtained when the blade enters the position from 100 mm to 10 mm from the bottom of the toner powder layer at the sixth time. E is the sum Et of the torque and vertical load.

(Ii) Measurement of Ec The operation of (4)-(i)-(b) is similarly performed on the compressed powder layer, and the blade is advanced from the position of 100 mm to the position of 10 mm from the bottom of the toner powder layer. Let Ec be the total Et of the rotational torque and vertical load obtained at the time.

<Number average particle diameter of primary particles of silica fine particles>
The measurement of the number average particle diameter of primary particles of silica fine particles was increased by 100,000 times by adding FE-SEM S-4800 (manufactured by Hitachi, Ltd.) with 1 part by mass of silica fine particles added to 100 parts by mass of toner particles. A photograph of the surface of the toner particles was taken, and the particle size of 100 or more silica fine particles was measured using the enlarged photograph, and obtained from the arithmetic average. The particle diameter of the silica fine particles is counted as the absolute maximum length when the shape is spherical, and the major axis is counted as the particle diameter when it has a major axis and a minor axis.

<Method for Measuring Toner Weight Average Particle Size D4>
The weight average particle diameter (D4) of the toner is calculated as follows. As a measuring device, a precise particle size distribution measuring device “Coulter Counter Multisizer 3” (registered trademark, manufactured by Beckman Coulter, Inc.) using a pore electrical resistance method equipped with a 100 μm aperture tube is used. For setting the measurement conditions and analyzing the measurement data, the attached dedicated software “Beckman Coulter Multisizer 3 Version 3.51” (manufactured by Beckman Coulter, Inc.) is used. Note that the measurement is performed with 25,000 effective measurement channels.

  As the electrolytic aqueous solution used for the measurement, special grade sodium chloride is dissolved in ion-exchanged water so as to have a concentration of about 1% by mass, for example, “ISOTON II” (manufactured by Beckman Coulter, Inc.) can be used.

  Prior to measurement and analysis, the dedicated software was set as follows.

  On the “Change Standard Measurement Method (SOMME)” screen of the dedicated software, set the total count in the control mode to 50,000 particles, set the number of measurements once, and set the Kd value to “standard particles 10.0 μm” (Beckman Coulter) Set the value obtained using By pressing the “Threshold / Noise Level Measurement Button”, the threshold and noise level are automatically set. In addition, the current is set to 1600 μA, the gain is set to 2, the electrolyte is set to ISOTON II, and the “aperture tube flush after measurement” is checked.

  In the “Pulse to particle size conversion setting” screen of the dedicated software, the bin interval is set to logarithmic particle size, the particle size bin is set to 256 particle size bin, and the particle size range is set to 2 μm to 60 μm.

  The specific measurement method is as follows.

  (1) About 200 ml of the electrolytic aqueous solution is put in a glass 250 ml round bottom beaker exclusively for Multisizer 3, set on a sample stand, and the stirrer rod is stirred counterclockwise at 24 rotations / second. Then, the dirt and bubbles in the aperture tube are removed by the “aperture flush” function of the dedicated software.

  (2) About 30 ml of the electrolytic aqueous solution is put into a glass 100 ml flat bottom beaker. In this, "Contaminone N" (nonionic surfactant, anionic surfactant, 10% by weight aqueous solution of neutral detergent for pH7 precision measuring instrument cleaning, made by organic builder, manufactured by Wako Pure Chemical Industries, Ltd. About 0.3 ml of a diluted solution obtained by diluting 3) with ion-exchanged water is added.

  (3) Two oscillators with an oscillation frequency of 50 kHz are incorporated with the phase shifted by 180 degrees, and an ultrasonic disperser “Ultrasonic Dissipation System Tetra 150” (manufactured by Nikkaki Bios Co., Ltd.) having an electrical output of 120 W is prepared. About 3.3 l of ion-exchanged water is placed in the water tank of the ultrasonic disperser, and about 2 ml of Contaminone N is added to the water tank.

  (4) The beaker of (2) is set in the beaker fixing hole of the ultrasonic disperser, and the ultrasonic disperser is operated. And the height position of a beaker is adjusted so that the resonance state of the liquid level of the electrolyte solution in a beaker may become the maximum.

  (5) In a state where the electrolytic aqueous solution in the beaker of (4) is irradiated with ultrasonic waves, about 10 mg of toner is added to the electrolytic aqueous solution little by little and dispersed. Then, the ultrasonic dispersion process is continued for another 60 seconds. In the ultrasonic dispersion, the temperature of the water tank is appropriately adjusted so as to be 10 ° C. or higher and 40 ° C. or lower.

  (6) To the round bottom beaker of (1) installed in the sample stand, the electrolyte solution of (5) in which the toner is dispersed is dropped using a pipette, and the measurement concentration is adjusted to about 5%. . The measurement is performed until the number of measured particles reaches 50,000.

  (7) The measurement data is analyzed with the dedicated software attached to the apparatus, and the weight average particle diameter (D4) is calculated. The “average diameter” on the “analysis / volume statistics (arithmetic average)” screen when the graph / volume% is set by the dedicated software is the weight average particle diameter (D4).

  The method for producing toner particles of the present invention is not particularly limited as long as the above total energy can be achieved, and a known production method can be used.

  Among the known production methods, the toner particles of the present invention comprise a step of dispersing a radical polymerizable monomer and a colorant, then dispersing the droplets in an aqueous medium or the like so as to obtain a desired toner particle size, and performing suspension polymerization. It is preferable that the toner is a suspension polymerization toner in which toner particles are prepared. This is because the particle size distribution is sharp, the sphericity is high, and particles having a substantially uniform surface material can be formed, so that stable fluidity and excellent charging characteristics can be easily obtained.

  Hereinafter, the most suitable suspension polymerization method for obtaining the toner particles used in the present invention will be exemplified and the production method of the toner particles will be described.

  Dissolve or disperse the polymerizable monomer, colorant, polar resin, release agent and other additives as required uniformly using a disperser such as a homogenizer, ball mill, colloid mill, or ultrasonic disperser. In this, a polymerization initiator is dissolved to prepare a polymerizable monomer composition.

  Next, the polymerizable monomer composition is dispersed in an aqueous medium containing a dispersion stabilizer and granulated to form particles, and toner particles are produced by polymerizing the polymerizable monomer in the particles. To do.

  The polymerization initiator may be added at the same time when other additives are added to the polymerizable monomer, or may be mixed immediately before the polymerizable monomer composition is dispersed in the aqueous medium. .

  Also, a polymerization initiator dissolved in a polymerizable monomer or solvent can be added immediately after granulation and before starting the polymerization reaction.

  In the present invention, it is preferable to add an appropriate acid for pH adjustment at the time of dispersion, granulation, and before starting the polymerization reaction.

  As the acid used in the toner of the present invention, commonly used acids such as hydrochloric acid, sulfuric acid, and nitric acid can be used.

  By adjusting the aqueous solution during polymerization to an appropriate pH, it is possible to obtain a toner having more uniform charging performance.

  When a polar resin is added during the polymerization reaction from the dispersion step of the polymerizable monomer composition to the polymerization step, the polarity varies depending on the balance between the polarity of the polymerizable monomer composition to be toner particles and the aqueous dispersion medium. The presence state of the resin can be controlled.

  That is, by adding a polar resin, functional separation according to the resin layer is possible. Further, the toner particles obtained by the suspension polymerization method are preferable because they have a core-shell structure including a release agent component.

  Examples of the polar resin include polyester resin, epoxy resin, styrene-acrylic acid copolymer, styrene-methacrylic acid copolymer, and styrene-maleic acid copolymer.

  As the polymerizable monomer constituting the binder resin used in the toner of the present invention, generally used styrene-acrylic copolymer, styrene-methacrylic copolymer, epoxy resin, styrene-butadiene copolymer Coalescence is mentioned.

  As the polymerizable monomer constituting the binder resin, a vinyl polymerizable monomer capable of radical polymerization can be used. As the vinyl polymerizable monomer, a monofunctional polymerizable monomer or a polyfunctional polymerizable monomer can be used.

  Examples of the polymerizable monomer for constituting the binder resin include the following. Styrene; Styrenic monomers such as o- (m-, p-) methylstyrene, m- (p-) ethylstyrene; methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, propyl acrylate, Propyl methacrylate, butyl acrylate, butyl methacrylate, octyl acrylate, octyl methacrylate, dodecyl acrylate, dodecyl methacrylate, stearyl acrylate, stearyl methacrylate, behenyl acrylate, behenyl methacrylate, 2-ethylhexyl acrylate, Acrylic acid ester monomers such as 2-ethylhexyl methacrylate, dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate, diethyl acrylate, aminoethyl, diethylaminoethyl methacrylate, or methacrylic acid Ester-based monomers; butadiene, isoprene, cyclohexene, acrylonitrile, methacrylonitrile, acrylic acid amide, such as ene-based monomers methacrylamide.

  In the present invention, a crosslinking agent may be used when the binder resin is synthesized in order to increase the mechanical strength of the toner particles and to control the molecular weight of the THF soluble component of the toner.

  Examples of the bifunctional crosslinking agent include the following. Divinylbenzene, bis (4-acryloxypolyethoxyphenyl) propane, ethylene glycol diacrylate, 1,3-butylene glycol diacrylate, 1,4-butanediol diacrylate, 1,5-pentanediol diacrylate, 1,6 -Hexanediol diacrylate, neopentyl glycol diacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol # 200, # 400, # 600 diacrylate, dipropylene glycol diacrylate, polypropylene Glycol diacrylate, polyester-type diacrylate (MANDA Nippon Kayaku), and dimethacrylate instead of diacrylate Thing.

  The following are mentioned as a polyfunctional crosslinking agent. Pentaerythritol triacrylate, trimethylol ethane triacrylate, trimethylol propane triacrylate, tetramethylol methane tetraacrylate, oligoester acrylate and its methacrylate, 2,2-bis (4-methacryloxypolyethoxyphenyl) propane, diallyl phthalate, tri Allyl cyanurate, triallyl isocyanurate and triallyl trimellitate.

  The mold release agent used in the present invention includes petroleum wax such as paraffin wax, microcrystalline wax, and petrolatum and derivatives thereof; montan wax and derivatives thereof; hydrocarbon wax and derivatives thereof according to the Fischer-Tropsch method; polyethylene wax, polypropylene wax, and the like Polyolefin waxes and derivatives thereof, natural waxes and derivatives thereof such as carnauba wax and candelilla wax; higher fatty alcohols; fatty acids such as stearic acid and palmitic acid; acid amide waxes; ester waxes; hardened castor oil and derivatives thereof; System waxes; animal waxes and the like are used. Of these, paraffin wax, ester wax and hydrocarbon wax are particularly preferred from the viewpoint of excellent releasability.

  The following are mentioned as a polymerization initiator used for the toner of the present invention. 2,2′-azobis- (2,4-dimethylvaleronitrile), 2,2′-azobisisobutyronitrile, 1,1′-azobis (cyclohexane-1-carbonitrile), 2,2′-azobis Azo or diazo polymerization initiators such as -4-methoxy-2,4-dimethylvaleronitrile, azobisisobutyronitrile; benzoyl peroxide, methyl ethyl ketone peroxide, diisopropyl peroxycarbonate, cumene hydroperoxide, 2,4-dichlorobenzoyl Peroxide-based polymerization initiators such as peroxide, lauroyl peroxide, tert-butyl-peroxypivalate. The kind of the polymerization initiator varies slightly depending on the polymerization method, but is used alone or in combination with reference to the 10-hour half-life temperature.

  The toner of the present invention contains a colorant as an essential component in order to impart coloring power. Examples of the colorant preferably used in the present invention include the following organic pigments, organic dyes, and inorganic pigments.

  Examples of organic pigments or organic dyes as cyan colorants include copper phthalocyanine compounds and derivatives thereof, anthraquinone compounds, and basic dye lake compounds.

  Specific examples include the following. C. I. Pigment blue 1, C.I. I. Pigment blue 7, C.I. I. Pigment blue 15, C.I. I. Pigment blue 15: 1, C.I. I. Pigment blue 15: 2, C.I. I. Pigment blue 15: 3, C.I. I. Pigment blue 15: 4, C.I. I. Pigment blue 60, C.I. I. Pigment blue 62, C.I. I. Pigment blue.

  Examples of the organic pigment or organic dye as the magenta colorant include the following. Condensed azo compounds, diketopyrrolopyrrole compounds, anthraquinones, quinacridone compounds, basic dye lake compounds, naphthol compounds, benzimidazolone compounds, thioindigo compounds, perylene compounds.

  Specific examples include the following. C. I. Pigment red 2, C.I. I. Pigment red 3, C.I. I. Pigment red 5, C.I. I. Pigment red 6, C.I. I. Pigment red 7, C.I. I. Pigment violet 19, C.I. I. Pigment red 23, C.I. I. Pigment red 48: 2, C.I. I. Pigment red 48: 3, C.I. I. Pigment red 48: 4, C.I. I. Pigment red 57: 1, C.I. I. Pigment red 81: 1, C.I. I. Pigment red 122, C.I. I. Pigment red 144, C.I. I. Pigment red 146, C.I. I. Pigment red 150, C.I. I. Pigment red 166, C.I. I. Pigment red 169, C.I. I. Pigment red 177, C.I. I. Pigment red 184, C.I. I. Pigment red 185, C.I. I. Pigment red 202, C.I. I. Pigment red 206, C.I. I. Pigment red 220, C.I. I. Pigment red 221, C.I. I. Pigment Red 254.

  Examples of the organic pigment or organic dye as the yellow colorant include compounds typified by condensed azo compounds, isoindolinone compounds, anthraquinone compounds, azo metal complexes, methine compounds, and allylamide compounds.

  Specific examples include the following. C. I. Pigment yellow 12, C.I. I. Pigment yellow 13, C.I. I. Pigment yellow 14, C.I. I. Pigment yellow 15, C.I. I. Pigment yellow 17, C.I. I. Pigment yellow 62, C.I. I. Pigment yellow 74, C.I. I. Pigment yellow 83, C.I. I. Pigment yellow 93, C.I. I. Pigment yellow 94, C.I. I. Pigment yellow 95, C.I. I. Pigment yellow 97, C.I. I. Pigment yellow 109, C.I. I. Pigment yellow 110, C.I. I. Pigment yellow 111, C.I. I. Pigment yellow 120, C.I. I. Pigment yellow 127, C.I. I. Pigment yellow 128, C.I. I. Pigment yellow 129, C.I. I. Pigment yellow 147, C.I. I. Pigment yellow 151, C.I. I. Pigment yellow 154, C.I. I. Pigment yellow 155, C.I. I. Pigment yellow 168, C.I. I. Pigment yellow 174, C.I. I. Pigment yellow 175, C.I. I. Pigment yellow 176, C.I. I. Pigment yellow 180, C.I. I. Pigment yellow 181, C.I. I. Pigment yellow 191, C.I. I. Pigment Yellow 194.

  Examples of the black colorant include carbon black and those prepared by using the yellow colorant / magenta colorant / cyan colorant toned to black.

  These colorants can be used alone or in combination and further in the form of a solid solution. The colorant used in the toner of the present invention is selected from the viewpoints of hue angle, saturation, brightness, light resistance, OHP transparency, and dispersibility in the toner.

  In the present invention, when toner particles are obtained using a polymerization method, it is necessary to pay attention to the polymerization inhibitory property and water phase migration property of the colorant, and preferably, a hydrophobic treatment with a substance that does not inhibit polymerization is performed. It is better to apply it to the colorant.

  As the dispersion stabilizer used when preparing the aqueous medium, known inorganic and organic dispersion stabilizers can be used.

  Specifically, the following are mentioned as an example of an inorganic dispersion stabilizer. Tricalcium phosphate, magnesium phosphate, aluminum phosphate, zinc phosphate, magnesium carbonate, calcium carbonate, calcium hydroxide, magnesium hydroxide, aluminum hydroxide, calcium metasilicate, calcium sulfate, barium sulfate, bentonite, silica, alumina .

  Examples of the organic dispersant include the following. Polyvinyl alcohol, gelatin, methyl cellulose, methyl hydroxypropyl cellulose, ethyl cellulose, carboxymethyl cellulose sodium salt, starch.

  Commercially available nonionic, anionic and cationic surfactants can also be used. Examples of such surfactants include the following. Sodium dodecyl sulfate, sodium tetradecyl sulfate, sodium pentadecyl sulfate, sodium octyl sulfate, sodium oleate, sodium laurate, potassium stearate, calcium oleate.

  As the dispersion stabilizer used in preparing the aqueous medium used in the toner of the present invention, an inorganic poorly water-soluble dispersion stabilizer is preferable, and it is preferable to use a poorly water-soluble inorganic dispersion stabilizer that is soluble in acid. .

  In the present invention, when preparing an aqueous medium in which the above dispersion stabilizer is dispersed, a commercially available dispersion stabilizer may be used as it is.

  In order to obtain particles of a dispersion stabilizer having a fine uniform particle size, an aqueous medium may be prepared by generating a dispersion stabilizer in a liquid medium such as water under high-speed stirring.

  For example, when tricalcium phosphate is used as a dispersion stabilizer, a preferred dispersion stabilizer can be obtained by mixing sodium phosphate aqueous solution and calcium chloride aqueous solution under high speed stirring to form fine particles of tricalcium phosphate. Can do.

  In the toner of the present invention, a charge control agent can be mixed with toner particles and used as necessary. By adding a charge control agent, it is possible to improve and stabilize the charge characteristics, and to control the optimum triboelectric charge amount according to the development system.

  As the charge control agent, a known one can be used, and a charge control agent that has a high charging speed and can stably maintain a constant charge amount is particularly preferable.

  Further, when the toner particles are produced by a direct polymerization method, a charge control agent having a low polymerization inhibition property and a small amount of solubilized products in an aqueous medium is particularly preferable.

  Examples of the charge control agent that control the toner to be negatively charged include the following. Organic metal compounds and chelate compounds are effective, and monoazo metal compounds, acetylacetone metal compounds, aromatic oxycarboxylic acids, aromatic dicarboxylic acids, oxycarboxylic acids, and dicarboxylic acid-based metal compounds. Other examples include aromatic oxycarboxylic acids, aromatic mono- and polycarboxylic acids and metal salts thereof, anhydrides, esters, and phenol derivatives such as bisphenol. Further examples include urea derivatives, metal-containing salicylic acid compounds, metal-containing naphthoic acid compounds, boron compounds, quaternary ammonium salts, calixarene, and resin charge control agents.

  Among these, the polymer having a sulfonic acid functional group as a charge control agent is preferably a polymer or copolymer having a sulfonic acid group, a sulfonic acid group, or a sulfonic acid ester group.

  Hereinafter, production examples of toners used in Examples and Comparative Examples of the invention will be described.

  First, toner production examples used in Examples and Comparative Examples of the present invention will be described.

  The toner particles used in the examples and comparative examples of the present invention were toner particles produced by suspension polymerization. However, the toner particles in the present invention are not necessarily limited to this, and the pulverization method, emulsion polymerization, and the like. Toner particles obtained by an aggregation method or a dissolution suspension method can also be used.

<Production Example of Toner Particle (1)>
Toner particles 1 were produced by the suspension polymerization method as follows.

The following materials were mixed and stirred for 2 hours to dissolve the polar resin to obtain a polar resin-containing monomer composition.
Styrene 34.0 parts by mass N-butyl acrylate 30.0 parts by mass Polar resin (saturated polyester resin [produced from terephthalic acid and PO-modified bisphenol A: Mp = 9000, Tg = 72 ° C., acid value = 12. 0 mg KOH / g]) 5.0 parts by mass, charge control agent Bontron E-88 (manufactured by Orient Chemical Co., Ltd.) 1.0 part by mass In addition, the following materials were mixed and zirconia beads (made by Mitsui Mining Co., Ltd.) 3/16 inch) at 200 rpm for 3 hours, and the beads were separated to obtain a colorant dispersion.
-Styrene 36.0 parts by mass-Colorant C.I. I. Pigment Blue 15: 3 6.0 parts by mass
-Polar resin-containing monomer composition 70.0 parts by mass-Colorant dispersion 42.0 parts by mass The above materials were mixed. Subsequently, the mixture was heated to 60 ° C., and 10.0 parts by mass of wax (HNP-51: manufactured by Nippon Seiwa Co., Ltd.) was added. Next, 5.0 parts by mass of a polymerization initiator perbutyl O (manufactured by NOF Corporation) was added and stirred for 5 minutes.

On the other hand, 875 parts by mass of 0.1 mol / L-Na ₃ PO ₄ aqueous solution and 8.0 parts by mass of 10% hydrochloric acid were added to a container equipped with a high-speed agitator CLEARMIX (M Technique Co., Ltd.) It adjusted to 15000 rpm and heated to 60 degreeC. Here was added 1.0mol / L-CaCl ₂ aqueous solution 70 parts by mass, to prepare an aqueous medium containing a fine sparingly water-soluble dispersing agent _Ca 3 _{(PO 4) 2.} 5 minutes after the polymerization initiator was charged into the polymerizable monomer composition, the polysynthetic monomer composition at 60 ° C. was charged into an aqueous medium heated to 60 ° C., and the CLEARMIX was rotated at 15000 rpm. And granulated for 15 minutes. Thereafter, the stirrer was changed from a high-speed stirrer to a propeller stirring blade, and the mixture was reacted at 60 ° C. for 5 hours while refluxing. After completion of the polymerization, the liquid temperature was lowered to about 20 ° C., diluted hydrochloric acid was added to adjust the pH of the aqueous medium to 3.0 or less, and the poorly water-soluble dispersant was dissolved. Further, washing and drying were performed to obtain toner particles 1 having a weight average particle diameter (D4) of 5.96 μm.

<Production Example of Silica Fine Particle 1>
As a first treatment step, 10.0 parts by mass of 100 parts by mass of fumed silica (trade name AEROSIL 380S, specific surface area 380 m ² / g by BET method, number average diameter of primary particles 7 nm, manufactured by Nippon Aerosil Co., Ltd.) Dimethyl silicone oil was sprayed, and silicone oil treatment was performed in a fluidized state of silica. Thereafter, the temperature was raised to 300 ° C. with stirring, and the mixture was further stirred for 2 hours, whereby dimethyl silicone oil was baked on the fumed silica surface to complete the reaction.

  As the second treatment step, 30.0 parts by mass of hexamethyldisilazane (hereinafter also referred to as HMDS) is sprayed on the silica fine particles produced in the first treatment step, and the silane compound treatment is performed in the fluidized state of silica. I did it. This reaction was continued for 60 minutes, and then the reaction was terminated.

<Example of production of silica fine particles 2>
In the production example of silica fine particles 1, silica fine particles 2 were obtained in the same manner except that the first treatment step was changed to HMDS treatment and the second treatment step was changed to silicone oil treatment.

<Example of production of silica fine particles 3>
In the production example of silica fine particles 2, silica fine particles 3 were obtained in the same manner except that the second treatment step was not performed.

<Example of production of silica fine particles 4>
In the production example of silica fine particles 3, the fumed silica used is changed to (trade name AEROSIL 300, specific surface area 300 m ² / g by BET method, number average diameter of primary particles 7 nm, manufactured by Nippon Aerosil Co., Ltd.), and treated with dimethyl Silica fine particles 4 were obtained in the same manner except that the amount of silicone oil was changed to 30.0 parts by mass.

<Example of production of silica fine particles 5>
In the production example of silica fine particles 4, the fumed silica to be used is changed to (trade name AEROSIL300, specific surface area 300 m ² / g by BET method, number average diameter of primary particles 7 nm, manufactured by Nippon Aerosil Co., Ltd.), and treated with dimethyl Silica fine particles 5 were obtained in the same manner except that the amount of silicone oil was changed to 20.0 parts by mass.

<Example of production of titanium oxide fine particles 1>
As a first treatment step, 10.0 parts by mass of isobutyltrimethoxysilane is sprayed on the inside with respect to 100 parts by mass of titanium oxide fine particles (trade name MT-150A, manufactured by Teika Co., Ltd.) having a primary particle number average diameter of 15 nm. Then, the silane compound treatment was performed in a fluidized state of titanium. This reaction was continued for 60 minutes, and then the reaction was terminated.

  As the second treatment step, 10.0 parts by mass of dimethyl silicone oil was sprayed on the fine titanium particles produced in the first treatment step, and stirring was continued for 30 minutes. Thereafter, the temperature was raised to 190 ° C. with stirring, and the mixture was further stirred for 3 hours, whereby dimethyl silicone oil was baked on the titanium oxide surface to complete the reaction. Thereafter, crushing treatment was repeatedly performed with a jet mill until the aggregate of titanium oxide disappeared, and titanium oxide fine particles 1 were obtained.

<Example of production of titanium oxide fine particles 2>
In the production example of the titanium oxide fine particles 1, oxidation was performed in the same manner as in the production example of the titanium oxide fine particles 1 except that the primary particles were changed to titanium oxide fine particles having a number average diameter of 35 nm (trade name MT-500B, manufactured by Teika Co., Ltd.). Titanium fine particles 2 were obtained.

<Production Example of Toner 1>
Silica fine particles 1: 0.8 parts by mass and titanium oxide fine particles 1: 0.8 parts by mass are added to 1: 100.0 parts by mass of toner particles, and a Henschel mixer (manufactured by Mitsui Mining Co., Ltd.) is used. Toner 1 was obtained by mixing for minutes.

  Toner 1 had a weight average particle diameter (D4) of 5.96 μm, E of 401 mJ, and Ec / E of 1.90. Table 1 shows the physical properties of Toner 1.

<Production example of toner 2 to toner 11>
In the toner 1 production example, toner 2 to toner 11 were obtained in the same manner as in the toner 1 production example, except that the types and addition amounts of silica fine particles and titanium oxide fine particles added were changed to those shown in Table 1. . In the toner 11, no titanium oxide fine particles were added. Table 1 shows the physical properties of Toner 2 to Toner 11.

[Example 1]
LBP7700C (manufactured by Canon Inc.) was used as an evaluation machine. The cyan cartridge was modified and toner 1 was refilled. A cyan cartridge provided with the configuration of FIG.

In a low-temperature and low-humidity environment (15 ° C., 10% RH), a solid image with a toner loading of 0.45 mg / cm ² was printed, and the initial density unevenness was evaluated.

  Thereafter, ten similar solid images were output, and the density unevenness during continuous printing was evaluated for the tenth solid image.

  Further, after being left for 10 days in a low temperature and low humidity environment, one solid image was output, and density unevenness after being left was evaluated.

  A4 size Office 70 (manufactured by Canon Inc., basis weight 70 g / m 2) was used as the evaluation paper. The density unevenness was evaluated by measuring the image density at the center and both left and right ends of the solid image using a “Macbeth reflection densitometer RD918” (manufactured by Macbeth) and based on the following evaluation criteria. The evaluation results are shown in Table 2.

(Evaluation criteria)
A: The difference between the density at the center of the image and the density at the edge (thin side on the left and right) is less than 0.10.
B: The density difference is 0.10 or more and less than 0.20.
C: The density difference is 0.20 or more.

[Examples 2 to 11, Comparative Examples 1 and 2]
Using the toner and cartridge shown in Table 2, the same evaluation as in Example 1 was performed.

  The cyan cartridge in which convex portions having the same shape as the light guide member are arranged in a rib shape as shown in FIG. 11 is the cartridge 2, and the cyan cartridge in which convex portions having the same shape as the light guide member is not arranged as shown in FIG. And The evaluation results are shown in Table 2.

S Recording medium 1 (1a to 1d) Photosensitive drum 2 (2a to 2d) Charging roller 3 Scanner unit 4 (4a to 4d) Development unit 5 Electrostatic intermediate transfer unit 6 (6a to 6d) Cleaning member 7 Elastic member 8 Cleaning Support member 12 Pre-development bearing 13 Development back bearing 14 Front support pin 15 Back support pin 17 Cassette 25 (25a to 25d) Development roller 26 (26a to 26d) Cleaning unit 27 Cleaning frame 27a Removal toner chamber 28 Charging roller bearing 31 Development Frame body 34 Toner supply roller 35 Developing blade 36 Toner conveying member 36a Stirring shaft 36b Sheet member 40 Seal member 54 Feed roller 55 Registration roller pair 56 Drive roller 57 Followed roller 58 Primary transfer roller 59 Opposite roller 69 Secondary transfer roller 70 (7 A～70d) The process cartridge 72 the discharge roller 74 fixing unit 75 discharge unit 76 conveying roller pair 100 electrophotographic image forming apparatus 131 first developing frame 131d protruding portion 131e protruding portion 131f protruding portions (ribs)
131g Protrusion (rib shape)
132 Second developing frame 140 Remaining amount detecting means 141 Light guide member 141a Light emission side light guide portion 141b Light reception side light guide portion 141c Incident portion 141d Light emission side window 141e Light reception side window 141f Output portion 141t Convex region 150 Light emitting element 151 Light receiving element 152 Detection light 153 Spatial light path 200 Toner

Claims (4)

A developing method for developing an electrostatic latent image on an image carrier with toner using a developing device,
The developing device includes:
Toner and
A development chamber,
A toner storage chamber for storing the toner , which is disposed vertically below the developing chamber ;
A toner conveying member that is provided inside the toner accommodating chamber and conveys the toner against the gravity from the toner accommodating chamber to the developing chamber ;
Is provided inside the front Symbol toner chamber, and the light guide member for the toner amount detection,
Have
The toner conveying member is
An agitation shaft that can be rotated by an external driving force;
A sheet member attached to the agitation shaft and rotating together with the agitation shaft;
Have
Wherein the light guide member, Ri Contact the said sheet member with the rotation of the sheet member is first protrusion to elastically deform is formed,
The inside of the toner chamber, with reference to the position of the light guide member, along said longitudinal direction of the toner chamber, is provided with convex member projecting from the inner wall surface of the toner accommodating chamber,
The convex member is formed with a second convex portion,
In any cross-section in a direction orthogonal to a longitudinal direction of said toner accommodating chamber, and a cross-section first protrusion before SL becomes the maximum, when the second convex portion is overlapped with the cross section becomes maximum, two In the cross section, the shape of the first convex portion and the second convex portion overlap,
Using the restoring force that the sheet member restores when the sheet member passes through the first and second protrusions, the toner on the sheet member is removed from the toner storage chamber to the developing chamber. Transported to
The toner has toner particles containing a binder resin , a colorant, and a release agent,
The toner is, the following relation (1) and (2) you satisfied 300 (mJ) ≦ E ≦ 450 (mJ) (1)
1.00 ≦ Ec / E ≦ 2.50 (2)
(E in the above formulas (1) and (2) is perpendicular to the toner powder layer in the container while rotating the peripheral speed of the outermost edge of the propeller blade at 100 mm / s in the powder flowability analyzer. It represents the sum of the rotational torque and the vertical load obtained when the measurement is started from the position of 100 mm from the bottom surface of the powder layer and entered to the position of 10 mm from the bottom surface. Ec represents the sum of the rotational torque and the vertical load measured in the manner of measuring E in the toner powder layer to which a load of 3 kPa is applied.)
The developing method characterized by the above-mentioned. The convex member, a developing method according to 請 Motomeko 1 Ru rib member der extending in the longitudinal direction of the toner storage chamber. A developing step of developing the electrostatic latent image on the image carrier with toner using a developing device;
A transfer step of transferring the image developed in the development step to a transfer material with or without an intermediate transfer member; and fixing for fixing the image transferred on the transfer material to the transfer material Process,
An image forming method comprising:
The developing device includes:
Toner and
A development chamber,
A toner storage chamber for storing the toner , which is disposed vertically below the developing chamber ;
A toner conveying member that is provided inside the toner accommodating chamber and conveys the toner against the gravity from the toner accommodating chamber to the developing chamber ;
Is provided inside the front Symbol toner chamber, and the light guide member for the toner amount detection,
Have
The toner conveying member is
An agitation shaft that can be rotated by an external driving force;
A sheet member attached to the agitation shaft and rotating together with the agitation shaft;
Have
Wherein the light guide member, Ri Contact the said sheet member with the rotation of the sheet member is first protrusion to elastically deform is formed,
The inside of the toner chamber, with reference to the position of the light guide member, along said longitudinal direction of the toner chamber, is provided with convex member projecting from the inner wall surface of the toner accommodating chamber,
The convex member is formed with a second convex portion,
In any cross-section in a direction orthogonal to a longitudinal direction of said toner accommodating chamber, and a cross-section first protrusion before SL becomes the maximum, when the second convex portion is overlapped with the cross section becomes maximum, two In the cross section, the shape of the first convex portion and the second convex portion overlap,
Using the restoring force that the sheet member restores when the sheet member passes through the first and second protrusions, the toner on the sheet member is removed from the toner storage chamber to the developing chamber. Transported to
The toner has toner particles containing a binder resin , a colorant, and a release agent,
The toner is, the following relation (1) and (2) you satisfied 300 (mJ) ≦ E ≦ 450 (mJ) (1)
1.00 ≦ Ec / E ≦ 2.50 (2)
(E in the above formulas (1) and (2) is perpendicular to the toner powder layer in the container while rotating the peripheral speed of the outermost edge of the propeller blade at 100 mm / s in the powder flowability analyzer. It represents the sum of the rotational torque and the vertical load obtained when the measurement is started from the position of 100 mm from the bottom surface of the powder layer and entered to the position of 10 mm from the bottom surface. Ec represents the sum of the rotational torque and the vertical load measured in the manner of measuring E in the toner powder layer to which a load of 3 kPa is applied.)
An image forming method. The convex member, the image forming method according to 請 Motomeko 3 Ru rib member der extending in the longitudinal direction of the toner storage chamber.

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