JP2008225174A - Developer and development method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a developer and a development method providing homogeneously uniform and stable solid image density on a transfer material even under severe printing conditions. <P>SOLUTION: The developer is used in a development system that includes: a developing chamber composed of a developer carrier 1, a developer regulating member 2, a developer supply member 2, a developer conveying member and a development container; and a stirring chamber supplying a developer to the developing chamber, wherein the developing chamber has an entrance and an exit for the developer from and to the stirring chamber. The development system is characterized in that: in the cross-sectional area of a region in a cross section perpendicular to the longitudinal direction of the developing chamber, the region being surrounded by the development container excluding the developer conveying region and disposed vertically above the rotation center axis of the supply member, the cross-sectional area S1 in the upstream side along the conveying direction of the developer and the cross-sectional area S2 in the downstream side of the conveying direction defined by the developer conveying member, satisfy the relationship of S1<S2; the relationship between the bulk density (D1) and the standing bulk density (D2) of the developer satisfy 1.22≤D2/D1≤1.42 and 0.42≤D2≤0.55. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a developer and a developing method used in a recording method using an electrophotographic method, an electrostatic recording method, a magnetic recording method, or the like. More specifically, the present invention relates to a developer and a developing method used in a copying machine, a printer, and a fax machine in which a developer image is previously formed on an electrostatic latent image carrier and then transferred onto a transfer material to form an image.

  Along with the two-component development method that has been widely used in the past, recently there has been an increase in machines with a single-component development method having a simple structure. In addition to the conventional two-component development method, a method of replenishing a developer (hereinafter simply referred to as toner) for maintaining the image quality up to the running cost and the development life has been adopted not only in the conventional two-component development method.

  The replenishment type developing method is a toner having different physical properties such as charge amount and fluidity, such as a new toner to be replenished (hereinafter referred to as replenished toner) and a toner not used for development (hereinafter referred to as a durable toner). Exists in one developing chamber. If the difference between the physical properties of the replenishing toner and the durable toner is large, the halftone image is crushed, causing problems such as fogging on a white background and blurring on paper. In particular, the one-component development method has no equivalent to the carrier used in the two-component development method, so it is necessary to devise a development configuration that sufficiently agitates and conveys the replenishment toner and the durable toner, and stable image quality is achieved. Technical hurdles were high to achieve with a long life.

  On the other hand, in the copier and printer market, colorization and space saving of devices are rapidly progressing, and a configuration in which vertical circulation type developers are arranged in tandem is advantageous as a layout that satisfies them (for example, patents). Reference 1).

  However, when the endurance test was repeated with a one-component development sequential replenishment system using the vertical circulation type developer as mentioned above by the present inventors, a single-component developer circulating in the developer was obtained. Since the stirring share is always applied, the deterioration of the durable agent is promoted, and fogging occurs when the difference in physical properties between the replenisher and the durable agent widens.

  As shown in the above example, in the one-component development replenishment system, a light load circulation system that minimizes the deterioration of the developer is desired.

  As a result of various investigations on a lightly loaded one-component developer supply system, the present inventors have divided the developing container responsible for the developing process into a developing chamber and a stirring chamber that temporarily retains the developer and governs gentle circulation of the agent, It has been discovered that a system in which a developer is circulated by providing an inlet and an outlet that connect these two chambers is advantageous for extending the service life satisfying the replenishment system (see, for example, Patent Document 2).

  An example of the light load circulation type developing device and the circulation method will be described below with reference to the drawings.

  FIG. 8 shows a cross-sectional view perpendicular to the longitudinal direction of the developing device, and FIG. 9 shows a longitudinal circulation diagram of the developing device. Reference numeral 11 denotes a developing device. The developing device 11 includes two chambers, 10 developing chambers and 9 stirring chambers. A wall 16 separating the two chambers is provided between the developing chamber 10 and the stirring chamber 9, and an opening 19 (hereinafter referred to as an inlet) and an opening 20 (hereinafter referred to as an inlet) are provided at both ends of the wall 16 so that toner can come and go. Called an outlet). In the developing chamber 10, 1 is a developing roller, 2 is a developer supply roller, 3 is a developer regulating member, and 12 is a developing container. Parallel to the developer supply roller 2, four screws are arranged, and a stirring chamber 9 is arranged facing the screw 4 with the wall 16 interposed therebetween. The screw 4 is provided above the rotation center axis of the supply roller in order to optimally perform the two effects of supplying the toner to the supply roller 2 and returning the toner to the stirring chamber 9.

  By detecting the image printing ratio information and the toner amount in the stirring chamber, a toner replenishing operation corresponding to the detected information is performed by the replenishing device 8, and the replenished toner passes through the opening 6 and is dropped into the stirring chamber 9. The agitating member 5 disposed in the agitating chamber 9 can level the toner, but does not have a further conveying ability. Therefore, no matter how much the stirring member 5 in the stirring chamber 9 rotates, the toner is not positively conveyed to the inlet 19. In this case, the movement of the toner in the stirring chamber is such that the toner sent to the outlet 20 from the opening and the replenished toner rises in the stirring chamber 9 and is leveled as the stirring member 5 rotates. By repeating the above, the movement D gradually spreads in the stirring chamber 9. By repeating this operation, the toner finally reaches the inlet 19 and falls into the developing chamber 10 from the opening due to its own weight, and the toner is supplied to the supply roller 2.

  The supply roller 2 rubs against the developing roller 1 and rotates in the direction of the arrow to apply toner to the developing roller 1, and passes through a regulating member 3 that is in contact with the rotation of the developing roller 1, thereby thinning the layer. The toner coat layer thus formed is formed on the developing roller 1. Toner that has not been used for development due to low printing or the like is peeled off from the developing roller 1 by the supply roller 2, then transported to the screw 4, passes through the outlet 20, and is returned to the stirring chamber. In this way, the toner circulation in the vertical direction is created, and the replenishment toner and the durable toner can be sufficiently stirred and conveyed. Further, since the toner is not always loaded by the screw, the deterioration of the toner is suppressed, and a long life suitable for the replenishing system is achieved.

  However, it has been found that when an image having a high printing rate is continuously printed using this developing device, a phenomenon occurs in which the image density differs in the longitudinal direction of the developing device. The result is shown in FIG. As shown in FIG. 11, the image density was different along the toner conveyance direction by the screw 4 of the developing device. When the toner replenishment operation is continuously performed and the replenishment toner existing ratio in the stirring chamber becomes higher than the durable toner, the replenishment toner existing ratio of the toner layer on the developing roller near the developing chamber entrance becomes high. It was due to. This is because, in a circulation path having an inlet and an outlet, a large amount of toner supplied from the inlet is coated on the developing roller on the upstream side in the transport direction.

  Since the replenishment toner has a high charge amount, the coating tends to be thin on the developing roller. On the contrary, the durable toner has a low charge amount and tends to be thick on the developing roller. As a result, when a portion where the replenishment toner is present on the developing roller is high and a portion where the replenishment toner is present is low, the density is low in the portion where the replenishment toner is high and the concentration is high in the portion where the replenishment toner is low. It is thought to be due to this. This phenomenon was particularly remarkable in a high-temperature and high-humidity environment where the charge amount between the durable toner and the replenishing toner tends to vary.

JP-A-11-24382 JP 2006-99043 A

  SUMMARY OF THE INVENTION An object of the present invention is to provide a developer and a developing method in which the disadvantages of the prior art are greatly improved and a solid image density on a transfer material is uniformly uniform and stable even in a severe print case.

  An object of the present invention is to provide a developer that functions favorably as a replenishment system in both high temperature and high humidity and low temperature and low humidity conditions, and is less susceptible to image density fluctuations and fogging due to differences in charging characteristics between durable toner and replenishment toner. It is to provide a developing method.

  An object of the present invention is to provide a high-quality image over a long period of time by suppressing image defects caused by member contamination in the developing device even in repeated use.

The present invention includes at least a developer carrying member for carrying and developing a developer, a developer regulating member that is in contact with the surface of the developer carrying member to regulate the developer, and the developer carrying member. A developer supply member for supplying the developer, a developer transport member provided above the rotation center axis of the developer supply member and transporting the developer in the longitudinal direction of the developer carrier, and the development A developer container containing a developer to be supplied to the developer carrier, the developer carrier, the developer regulating member, the developer supply member, the developer transport member, and the developer container. A developer for use in a developing method having a stirring chamber for supplying a developer to the chamber, the developing chamber having an inlet and an outlet for the developer from the stirring chamber;
The developing method includes a developer having a cross-sectional area vertically surrounded by a supply member rotation central axis in a region surrounded by the developer container excluding a developer transport region in a cross section perpendicular to the longitudinal direction of the developing chamber. The relationship between the cross-sectional area S1 on the upstream side in the transport direction of the developer generated by the transport member and the cross-sectional area S2 on the downstream side in the transport direction satisfies S1 <S2.
The developer is characterized in that the relationship between the bulk density (D1) and the static bulk density (D2) satisfies D2 / D1 = 1.22 to 1.42, and D2 = 0.42 to 0.55. And

  By adopting the above-described configuration, the present invention can provide a one-component developing and replenishing system that is uniform in the longitudinal direction and is suitable for graphic printing, and has a stable image quality for a long time even after a severe print case. Can be offered over.

  Further, the toner and the developing method of the present invention suitably function as a replenishment system in both high temperature and high humidity and low temperature and low humidity conditions, and image density fluctuations and fogging due to charging characteristics difference between the durable toner and the replenishment toner occur. It is possible to provide an excellent visible image with a small amount of data over a long period.

  Further, the toner and the developing method of the present invention are stable at light load in the toner circulation in the developing device, so that deterioration of the toner is suppressed even during repeated use, and image defects caused by contamination of the members in the developing device. Can be prevented, and a high-quality image can be provided over a long period of time.

  In the developing device in which the developer circulates in the longitudinal direction in the developing chamber, the present inventors uniformly coat the replenished toner with the length of the developing roller even in a severe print case in a harsh environment. A development system that does not easily cause a difference in density between the side and the downstream side and that does not easily cause image defects such as fogging has been intensively studied. As a result, it has been found that the above object can be achieved by controlling the bulk density of the toner within a certain range and adopting a configuration in which the cross-sectional area of the developing chamber is different between the upstream side and the downstream side in the developing device in which the toner circulates.

As shown in FIG. 1, a specific developing device configuration includes a developer carrying member 1 for carrying a developer and performing development, and a developer that is in contact with the surface of the developer carrying member and regulates the developer. A regulating member, a developer supplying member 2 for supplying the developer to the developer carrying member, and a developer conveying member in the longitudinal direction of the developer carrying member, provided above the rotation center axis of the developer supplying member. A developer conveying means 3, a developing chamber composed of an inner wall for storing the developer to be supplied to the developer carrying member, and a stirring chamber for supplying the developer to the developing chamber. In a cross section perpendicular to the longitudinal direction of the developing chamber of the developing device having an inlet and an outlet for the developer from
Surrounded vertically above the supply member rotation center axis in a region surrounded by the back surface of the developer regulating member, the outer periphery of the developer carrier, the outer periphery of the developer supply member, and the wall surface of the developer chamber excluding the developer transport region. In the cross-sectional area, the relationship between the cross-sectional area S1 on the upstream side in the transport direction of the developer generated by the developer transport means and the cross-sectional area S2 on the downstream side in the transport direction satisfies S1 <S2.

  With the above configuration, the size of the upward blowing from the supply roller generated on the upstream side of the developing roller contact nip portion of the supply roller can be changed along the conveyance direction. Specifically, as shown in FIG. 3, by reducing the cross-sectional area on the upstream side in the transport direction where the ratio of the replenished toner increases, the size of the blowout from the supply roller is increased, and the flow of toner supply is reduced. be able to.

Further, by increasing the cross-sectional area on the downstream side in the conveying direction where the ratio of the replenished toner is low, the size of the blowout from the supply roller is weakened to facilitate toner supply. As a result, the toner supplied from the developing chamber inlet can be coated uniformly over the entire surface of the developing roller, so that density unevenness can be improved and stable toner circulation can be generated.
By adopting the above configuration, it is possible to suppress the occurrence of a density difference in the longitudinal direction even in severe environments and print cases. As a one-component replenishment development system that can handle graphic patterns with high print output and photo image quality, stable image quality can be maintained.

  Embodiments relating to an image forming method and a developing device unit according to the present invention will be described with reference to the drawings. The embodiments described below exemplarily illustrate the present invention, and the dimensions, materials, shapes, relative arrangements, and the like of the components described below, unless otherwise specified. However, the scope of the present invention is not limited thereto.

  FIG. 6 is a schematic sectional view of an image forming apparatus for carrying out the image forming method according to the present invention, and FIG. 1 shows a schematic configuration of the developing apparatus according to the present invention and its vicinity.

  At the central portion of the image forming apparatus, an electrophotographic photosensitive member (hereinafter simply referred to as a “photosensitive member”), for example, a drum-shaped image carrier, that is, a photosensitive drum 29 is rotatable in the direction of the arrow. When the image forming operation is supported, the charging unit 31 uniformly charges the surface of the photosensitive drum 29, and then, for example, a laser irradiation unit 32 as an exposure unit exposes the surface corresponding to the image information. And an electrostatic latent image is formed on the surface. This electrostatic latent image is then visualized by the developer supplied to the photosensitive drum 29 by the developing device 11, and a so-called toner image is formed. Next, the toner image is electrostatically transferred onto the recording material P by a transfer electric field formed between the photosensitive drum 29 and the transfer roller 33 by, for example, a transfer roller 33 as a transfer unit. Thereafter, the unfixed toner image on the recording material P is permanently fixed on the recording material P by heat and pressure by the fixing device 34. The transfer residual toner remaining on the surface of the photosensitive drum 29 after the transfer of the toner image is removed by, for example, a cleaning device 30 including a blade-shaped cleaning member, and the photosensitive drum 29 can continue to form an image. Become. The process speed of the image forming apparatus used in the present invention, that is, the peripheral speed of the photosensitive drum 29 corresponds to any process speed from a low speed of 40 mm / sec to a high speed of 300 mm / sec, but from 100 mm / sec to 200 mm / sec. When the developing peripheral speed and the toner transport speed are interlocked, the toner circulation and durability are excellent. The peripheral speed of the developing roller 1 is 1.0 to 2.0 times the drum peripheral speed, and the peripheral speed ratio 1.3 to 1.7 times satisfies the image quality and durability. The most suitable range above.

FIG. 1 showing a developing device showing an embodiment of the present invention uses the same reference numerals as those in FIG. The developing container 12 is partially open on the side facing the photosensitive drum 18, and the developing roller 1 as a developer carrying member can be rotated in the direction of the arrow so as to be partially exposed from the opening. It is supported by. The developing roller 1 has an outer diameter composed of a low-hardness rubber material or foam such as silicone or urethane having a volume resistivity of 10 ² Ωcm to 10 ¹⁰ Ωcm in which a conductive agent such as carbon is dispersed, and a combination thereof. This is a 20 mm semiconductive elastic roller. The developing roller 1 includes an elastic body and is in contact with the photosensitive drum 29 with a predetermined contact pressure. The supply roller 2 as a developer supply / collection means is an elastic roller including an elastic body, and is arranged in contact with the development roller 1 with an insulating sponge roller having an outer diameter of 16 mm. The developing container 12 is provided with a blade 3 as a developer layer pressure regulating member so as to pressurize the developing roller 1. The blade 3 is a leaf spring made of SUS and is in contact with the developing roller 1 with a predetermined contact pressure. The toner supplied onto the developing roller 1 is subjected to layer thickness regulation and charge imparted by the blade 3 to form a thin layer of toner on the developing roller 1 and supplied to the developing region. Further, the toner that does not contribute to the development and is still carried on the developing roller 1 is peeled off from the developing roller 1 by rubbing with the supply roller 2. A part of the toner is supplied again onto the developing roller 1 by the supplying roller 2 together with the toner newly supplied onto the supplying roller 2, and the rest is returned to the developing container 12. In the present embodiment, the supply roller 2 has two functions as a developer supply and recovery means.

  In the toner hopper 8 which is a toner replenishing mechanism, a stirring member 7 for releasing the toner in the toner hopper 8 and a replenishment for replenishing toner (usually non-magnetic one-component toner) from the toner hopper 8 to the stirring chamber. A roller is disposed on the opening 6. In response to a replenishment command from the developing device, a constant amount of toner per predetermined driving time is replenished to the agitation chamber, and the toner amount in the developing container 12 is always kept constant. As a replenishment command system, there are a system in which a piezo sensor is provided in the developing container to know the presence or absence of toner, a light detection system, an inductance detection system, and a system for calculating the amount of toner consumed from the image printing ratio. In this embodiment, a light detection type toner amount sensor is provided in the stirring chamber, and an insufficient amount of toner is supplied from the supply mechanism. Further, the light detection type toner amount sensor itself is not shown because it is generally widely used.

  The developing device 11 is divided into two upper and lower chambers by a partition wall. The lower side including the developing carrier and the agitating and conveying member is referred to as a developing chamber 10, and the upper side including the agitating member 5 is referred to as an agitating chamber 9. The developing chamber 10 and the stirring chamber 9 are connected only by openings provided only at both ends. A screw 4 that is a longitudinal conveying member is disposed in the developing chamber 10. The screw 4 conveys the toner in the developing chamber in the longitudinal direction, sends the toner falling from the opening of the inlet 19 toward the central longitudinal direction of the developing chamber 10, and conveys the toner in the developing chamber 10 to the opening of the outlet 20. Then, it performs the role of sending it out to the stirring chamber 9 again.

  A stirring member 5 provided with a plurality of blades is provided in the stirring chamber 9, and the blades alternately stir up the toner by rotating to stir the developer. The screw 4 and the agitating member 5 are connected to the developing roller 1 and the sponge roller 2 by a gear (not shown), and rotate together during image formation, that is, while the developing roller is rotating, to complete the image formation. At the same time, the rotation stops.

  As shown in FIG. 1, the developing chamber 10 in the present invention has a shape in which the cross section of the developing chamber on the upstream side in the transport direction is different from the cross section of the developing chamber on the downstream side in the transport direction, and is filled with toner in the developing chamber. The volume is different.

  As shown by the hatched portion in FIG. 1, S is defined as a cross-sectional area surrounded by the developing container 12 excluding the screw conveyance region in a region vertically above the rotation center axis of the supply roller. The conveyance area | region by a screw is an area | region enclosed by the highest point and lowest point of a screw shape. As a method of changing the cross-sectional area of the developing chamber, there are a method of newly installing a developing chamber filling block having the shape shown in FIG. 2 in a conventional developing chamber, a method of designing a frame of the developing chamber by a mold in advance, and the like. In the present embodiment, as shown in FIG. 1a, the closest distance between the supply roller 2 and the newly-filled block in the developing container 12 is set to 3 mm at the upstream start point in the transport direction, and as it goes downstream in the transport direction, The closest distance changes continuously. Further, as shown in FIG. 1b, the closest distance is 5 mm at the center in the transport direction, and the closest distance is 7 mm at the final point downstream in the transport direction as shown in FIG. 1c. It has changed. The cross-sectional area S1 on the upstream side in the conveyance direction indicated by the oblique line in FIG. 1a is smaller than the cross-sectional area S3 on the downstream side in the conveyance direction indicated by the oblique line in FIG. 1c. Yes.

  Next, toner circulation in the developing device 11 will be described with reference to a longitudinal sectional view of the developing device 11 shown in FIG. The toner in the developing chamber 10 is conveyed in one longitudinal direction by the screw 4 and is sent to the stirring chamber 9 from the opening of the outlet 20 by the pressure C. Further, the toner replenished from the toner replenishing mechanism 8 is replenished to the outlet 20 side in the stirring chamber 9 in order to take the stirring time in the stirring chamber 9. The replenished toner is leveled while being stirred by the stirring member 5. By repeating this movement, the replenished toner finally reaches the inlet 19 by the movement D spreading into the stirring chamber, and is supplied into the developing chamber 10 from the inlet 19.

  The toner supplied to the developing chamber 10 supplies the toner to the supply roller 2, and the toner is supplied to the development roller 1 by rubbing the supply roller 2 and the development roller 1. When the supply roller 2 is rubbed against the developing roller 1, a part of the toner contained in the supply roller that has not been applied to the developing roller 1 is brought into contact between the supply roller 2 and the developing roller 1 by the compression action and rotation action of the sponge. The toner contained in the sponge part of the supply member is blown out from the part. By continuously rotating the supply roller 2, the flow of the toner discharged from the supply roller 2 has an upward direction E shown in FIG. Further, the toner is changed from a static state to a dynamic state by rotating the supply roller 2. By being in a dynamic state, the fluidity of the toner is increased, thereby lowering the bulk density, requiring a large volume even with the same weight, and increasing the toner agent surface in the developing chamber 10. Due to the flow E discharged from the supply roller 2 and the rise of the toner agent surface due to the rotation of the supply roller 2, the toner reaches the conveyance area of the screw 4 and is conveyed by the screw 4. The conveyance amount of the screw 4 is mainly determined by the screw shape, screw rotation speed, and the like.

  When S in the conventional developing chamber is constant at each longitudinal point, as shown in FIG. 10, the force in the flow direction E due to the toner blowing is equal at each longitudinal point. For this reason, the toner flow F supplied from the inlet 19 is large at the upstream portion in the transport direction, and the toner flow F supplied from the inlet 19 is gradually decreased toward the downstream in the transport direction.

  On the other hand, by reducing S on the upstream side in the transport direction as indicated by the hatched portion S1 in FIG. 1, the force in the upward flow direction E of the toner due to the blowing from the supply roller is increased as shown in FIG. Can do. Accordingly, the toner supply flow F can be relaxed on the upstream side in the transport direction, and the frequency of the toner supply flow direction F toward the supply roller can be reduced. Further, the replenishment toner existing ratio can be suppressed on the upstream side in the transport direction. In this way, even if the toner supply is regulated to some extent upstream in the transport direction, the toner supply is insufficient because it is a region where sufficient toner is supplied because it is close to the toner supply inlet 19 from the stirring chamber 9 to the developing chamber 10. That's not true.

  Further, by increasing the cross-sectional area S on the downstream side in the transport direction, as shown in FIG. 3, the direction E in the upward flow direction due to blowing from the supply roller 2 becomes smaller than that on the upstream side in the transport direction. For this reason, the frequency of the toner supply flow F toward the supply roller 2 increases, and the toner can be sufficiently supplied to the supply roller 2. Further, by maintaining a sufficient volume on the downstream side, toner packing due to toner conveyance of the screw 4 does not occur.

  In this way, the flow F of the toner supply can be reduced by increasing the size of the flow E caused by the toner blowing from the supply roller on the upstream side in the transport direction. Further, the toner flow F can be increased by gradually decreasing the size of the flow E caused by the toner blowing out of the supply roller along the downstream side in the transport direction, and the toner supplied from the inlet 19 can be transferred to the developing roller 1. Can be coated uniformly in the longitudinal direction.

  Next, the effect of improving the density difference in the longitudinal direction when the image forming apparatus of the present invention described above is used will be specifically described with reference to FIG.

  FIG. 4 shows an all-black image printed after continuously printing up to 25000 images with a printing rate of 1% in A4 size in a high-temperature and high-humidity environment, and then printing 100 images with a printing rate of 40% in A4 size. Density data by Macbeth reflection densitometer. As shown in the graph of FIG. 4, by making the cross-sectional area S larger toward the downstream side in the conveyance direction, the supply toner can be easily coated on the developing roller 1 in the longitudinal direction. As a result, a solid image with a small density difference can be printed along the transport direction.

  As described above, the toner supplied from the stirring chamber 9 is partially coated in the vicinity of the developing chamber inlet 19 by enlarging the cross-sectional area S of the hatched portion along the transport direction as shown in FIG. This is no longer the case. Further, the toner supply can be relaxed along the transport direction, and the toner supplied from the inlet can be uniformly coated in the longitudinal direction over the entire developing roller, and density unevenness can be improved in any environment and print case.

  In the example of the embodiment of the present invention, the example in which the developing chamber filling block having the shape shown in FIG. 2 is used is described. However, the cross section S is small up to the central portion in the transport direction as shown in FIG. The shape may have a large cross-sectional area S from the middle stream to the downstream. Further, the surface facing the supply roller 2 as shown in H of FIG. In the present invention, it is important that the cross-sectional area S increases toward the downstream in the transport direction, and continuously increases from the cross-sectional area S1 on the upstream side in the transport direction to the cross-sectional area S2 on the downstream side in the transport direction. This is the most preferable configuration because the toner transportability is more stable.

  FIG. 7 is an example of an image forming apparatus when the developing device according to the present invention is used in a color image forming apparatus equipped with a plurality of process cartridges, and is a schematic cross-sectional view of an inline full color laser printer using an electrophotographic process. It is.

  In the color image forming apparatus shown in FIG. 7, the developing device 11 (Y, M, C, K) of the same form described in FIG. 1 is integrated with the photosensitive drum 29, the charging roller 31, and the cleaner unit 30. The Further, four process cartridges are configured as process cartridges that can be exchanged for the image forming apparatus with a predetermined endurance life and each accommodates toners of four colors of yellow, magenta, cyan, and black that can be attached to and detached from the image forming main body. It has. A toner hopper similar to that shown in FIG. 1 is disposed as a toner hopper 8 (Y, M, C, K) in a replaceable manner in the image forming apparatus. The configuration and operation of the photosensitive drum, developing roller, charging roller, etc. in each process cartridge are the same as those of the image forming apparatus described with reference to FIG.

  The toner images formed on the surface of the photosensitive drum 29 are formed on the intermediate transfer body 35 in accordance with the arrangement order of the yellow, magenta, cyan, and black process cartridges, and transferred onto a transfer material conveyed by a paper feed roller. Next, it is heated and pressure-fixed by a fixing device (not shown) and discharged as a full-color image.

  In such a full-color image forming apparatus, a multi-color image is superimposed on a sheet of paper, so that a level much higher than that of a monochrome model is required for density unevenness and fog. The developing method described in the present invention can be more suitably used for such a full-color image forming apparatus.

  In addition, since these component parts are of a cartridge type that is easy to attach and detach, these consumable parts can be easily replaced. Therefore, the maintainability of the image forming apparatus is greatly improved. Also, by exchanging the cartridge, important components of the electrophotography are replaced with new ones, so that a high-quality image can always be maintained.

  Next, the developer (toner) used in the developing method of the present invention will be described.

  In the toner of the present invention, the relationship between the bulk density (D1) and the stationary bulk density (D2) satisfies D2 / D1 = 1.22 to 1.42, and D2 = 0.42 to 0.55. It is essential. The developing device used in the developing method of the present invention uses the discharge of the toner from the developing supply roller and the upstream volume in the toner circulation path to be narrow and the downstream volume to be widened. The density of the toner is made uniform by controlling the mixing state of the toner and the replenishing toner to be uniform. In order to further improve the image quality, the present inventors have studied the above developing method in all test cases. As a result, when low-printed images are continuously endured in harsh environments such as low-temperature and low-humidity environments and high-temperature and high-humidity environments, damaged durable toner accumulates in the developer container by repeating the circulation cycle. Go. Then, it was found that if high print output continues in this state, the old and new agents are poorly agitated and new image quality problems such as fogging and density fluctuation caused by toner having a difference in physical properties occur.

  As a result of intensive studies by the present inventors in order to solve the above-mentioned problems, a durable toner can be obtained by highly controlling the static and dynamic density characteristics of the toner with respect to the developer container whose volume is inclined in the longitudinal direction. And widening the difference in physical properties of the replenishment toner. The new and old toners can be mixed with high efficiency, suitable circulation is achieved through durability, and a high-quality one-component developer supply system that can withstand graphic printing with stable longitudinal density has been completed. .

D1 and D2 of the toner of the present invention are defined by the bulk density obtained according to the following measurement procedure.
1) Add 100 g of toner mixed well into a 500 ml measuring cylinder, and cover with Saran Wrap (Asahi Kasei Life & Living).
2) The operation of turning the graduated cylinder upside down and returning it to the original position is repeated 15 times, and the time when the graduated cylinder is placed at the 15th time is set to 0 second. The settling surface of the toner gradually sinking is visually read, the density read from the toner surface at 60 seconds is D1 (g / cm ³ ), and the density read from the toner surface at 600 seconds is D2 ( g / cm ³ ).

  The reason why D1 is defined as the bulk density at 60 seconds after shaking is that the toner circulates between the developing chamber and the stirring chamber of the present invention, and that the toner blows out from the developing supply roller and the volume in the developing chamber is in the circulation direction. In the developing method using the fact that the upstream side of the toner is narrow and becomes wider toward the downstream side, the bulk density of the flowing toner shows an important factor, and the dynamic powder density characteristic corresponding to the time of image formation and the This is because it has been found that the toner bulk density is generally correlated.

  Further, the standing bulk density D2 of the toner that has been sufficiently tightened at 600 seconds after shaking corresponds to the toner density in a state where the toner is left standing for a long time in a developing container that is not in use in a copying machine or a printer.

  In the developing device that repeatedly starts and stops, the D2 / D1 is adjusted to a density ratio of 1.22 to 1.44, whereby the old and new toners are efficiently mixed and the D2 is controlled to 0.42 to 0.55. Thus, an ideal circulation cycle in which toner conveyance is stable is formed. For this reason, it is possible to supply toner having stable physical properties to the development area over a long period of time, and thus, it is possible to achieve a long-life stable image quality.

  A developer having D2 / D1 of less than 1.22 shows a powder state that has already been tightened to a state close to the static density in 60 seconds. In the configuration of the developing machine of the present invention, the toner that has not been used for development is collected by the development supply roller and blown out, and once returned to the stirring chamber by the conveying screw, has a mixing point with the fresh supply toner. At the mixing point of the old and new toner, the developer whose D2 / D1 is less than 1.22 has no difference in bulk density between the old and new toner. It is difficult to mix well.

  Especially in cases where a high print command is issued when durability has advanced in the low print mode, mixing of fresh supply toner, which tends to be oversupplied, and durable toner tends to be insufficient, causing image defects such as fogging and density gradients. cause. In addition, if the low-printed image is output intermittently, the durability life is shortened due to accumulation of defective replacement of old and new toner when viewed in a long-term range.

  On the other hand, a developer with D2 / D1 exceeding 1.42 shows powder characteristics in which the bulk density changes greatly with respect to the elapsed time when it becomes bulky when mixed with air by blowing from a developer supply roller or the like. . Such a developer rich in change in the density characteristics of the one-component developer has an excessively high charge amount or a high degree of aggregation, and exhibits a characteristic of leaking with time. Such a developer has a large amount of change depending on the environment such as temperature and humidity, and the chargeability and cohesion tend to be unstable.

  In particular, in a low temperature and low humidity environment, when fresh toner is replenished when the durability has progressed, the amount of charge and bulk density of the old and new toners become the largest, and therefore, a phenomenon in which the old and new toners do not mix easily occurs. When the developer in such a state that the old and new toners are not sufficiently mixed reaches the developing region, fogging is deteriorated and a density gradient is generated.

  Note that it is essential that D2 / D1 of the toner of the present invention satisfies 1.22 to 1.42 and D2 satisfies the range of 0.42 to 0.55 at the same time.

  If D2 is less than 0.42, the toner conveyance speed is increased, and the old and new toners are likely to be mixed poorly, and the frequency of occurrence of defective images such as roughening of halftone images and uneven density increases. In particular, when durability is repeated in a high-temperature and high-humidity environment, a developer having a low bulk density is likely to be subjected to stress such as friction and pressure, and may cause fogging and member fusion.

  On the other hand, if D2 exceeds 0.55, the toner agitation and conveyance share increase, and the deterioration of the toner is promoted, the deterioration of image quality is accelerated, and the durability life is shortened. In some cases, partial packing may occur in the developing chamber or the agitation chamber, which may lead to fatal image defects such as streaks or blurs.

  In order to control D1 and D2 of the toner in the present invention, it is necessary to stably control the cohesiveness between the toners, the presence state of the release agent that determines the adhesion of the toner particles, the charging characteristics of the toner, This can be achieved by controlling the type and coating state of the external additive.

  Particularly effective methods include a method for suppressing the surface abundance of the release agent by devising a toner particle production method, and a method for sharpening the toner charge amount distribution by devising an external addition process. .

  As a method for suppressing the surface existing amount of the release agent, a method of producing toner particles by a suspension polymerization method is preferable because it is excellent in embedding the release agent. By adding a method that minimizes heat and shear damage to the toner particles during the drying process and a process that removes the supernatant from the slurry after the polymerization process, the amount of release agent on the toner surface can be further suppressed. It is preferable for stably controlling the bulk density of the present invention.

  In order to make the toner charge amount distribution uniform and sharp in the external addition process, the external additive is introduced in a state where the toner particles during stirring are sufficiently dispersed, and the external additive is uniformly attached to the toner particles. The method of suppressing the charge reversal component and preventing electrostatic aggregation, the method of adding a metal oxide other than silica and providing a charge leak site to suppress the charge-up, etc. are effective and preferable.

  The transportability index of the toner of the present invention is preferably 0.5 to 10.0.

  The transportability index is an index that represents the interference characteristic between the toner and the wall surface, which varies depending on the difference between the aggregation characteristics and friction characteristics between the toners. In the present invention, the circulation characteristics of the toner in the developing container together with the density characteristics of the toner. It is an important parameter that determines

  When the toner transportability index of the present invention is less than 0.5, the toner transportability in the developing device is poor, and therefore, a degrading agent tends to accumulate in the dead space, which may cause development problems. On the other hand, when the transportability index exceeds 10.0, the cohesiveness between the toners is high, and such a toner cannot withstand repeated shearing in the developing method of the present invention, and there is a possibility that the durable life may not be reached.

  The method for measuring the transportability index in the present invention is measured by a parts feeder (manufactured by Konica Minolta) shown in FIG. 12, and the mobility of toner in a state where a constant vibration is applied is indexed. Is. This transportability index is different from the fluidity evaluated by the static bulk density and angle of repose of the toner when it is stationary.

  Specifically, the parts feeder includes a drive source 40 for generating a specific vibration and a cylindrical ball 41 supported above the drive source 40. A spiral slope 42 is formed along the inner peripheral wall surface of the ball 41 to connect the bottom surface and the upper edge. Here, the slope 42 is disposed in such a manner that the upper end portion 43 thereof protrudes radially outward from the side wall of the ball 41 at the same height position as the upper end edge of the ball 41. In FIG. 1, 44 is a central axis of the ball 41, 45 is a saucer provided below the upper end 43 of the slope 42, and 46 is a weighing means connected to the saucer.

  In this parts feeder, the rotational power supplied by the drive source 40 is transmitted to the ball 41 to convert it into a vibrating motion that vibrates the ball 41 as a whole, and the return position of the vertical motion is arranged with an angle. By changing by the action of the provided spring, the toner positioned in the ball 41 is transferred upward along the slope 42 and falls onto the tray 45 from the upper end portion 43 of the slope 42.

Thus, the toner transportability index in the present invention is measured as follows. First, 1 g of toner is charged around the central axis E inside the ball 41, and the drive source 40 is driven under conditions of a frequency of 134.0 to 136.0 Hz and an amplitude of 0.59 to 0.61 mm. Next, the toner is moved upward along the slope E to reach the tray, and the drive source 40 is driven when the amount of toner reaching the tray measured by the weighing means 46 becomes 300 mg to 700 mg. Can be calculated using the following general formula.
(Transportability index) = (700-300) mg / (T700-T300) seconds

  In the above general formula, T300 indicates the time required to transfer 300 mg of toner to the tray, and T700 indicates the time required to transfer 700 mg of toner to the tray.

  The method for controlling the transportability index of the toner of the present invention can be controlled by controlling the abundance of the release agent on the surface of the toner particles, or by controlling the shape of the toner and the external additive.

  The toner of the present invention can maintain the image quality over a longer period by suppressing fluctuations in charging characteristics within a certain range in the measurement method described below.

  The toner of the present invention is mixed with a carrier at a ratio of 3% by mass, and the amount of charge when shaken for 120 seconds is (Q1). After the measurement of (Q1), further toner is added, and the mixing ratio with the carrier is 4% by mass. Q2 / Q1 is preferably controlled to 0.8 to 1.2 when the charge amount when shaken for 60 seconds after adjusting to (Q2).

  When Q2 / Q1 is smaller than 0.8, fog is likely to occur in the latter half of the durability in a high temperature and high humidity environment, which is not preferable.

  On the other hand, if Q2 / Q1 is greater than 1.2, the difference in charge amount between the durable toner and the replenishment toner tends to increase in the second half of the endurance in a low-temperature and low-humidity environment, and the coated toner in the development region exhibits a non-uniform charge amount distribution. This is not preferable because fog is likely to occur.

  The toner charge amount was measured using the Japan Imaging Society standard carrier N-01, with a 19.40 g carrier and 0.60 g toner placed in a 50 ml polyethylene bottle (container inner diameter: about 35 mm, height: about 75 mm). A measurement sample is weighed and left for 24 hours in an environment of a temperature of 23 ° C. and a relative humidity of 50%. Using a shaker Model-YS-8D (manufactured by Yayoi Co., Ltd.), set the sample bottle to be horizontal, blow off frictional charging at 120 seconds with an arm length of 140 mm, a swing angle of 40 °, and a shaking strength of 150 rpm. The quantity is defined as (Q1). Further, (Q1) Toner is further added to the sample bottle after the measurement so that the mixing ratio with the carrier becomes 4% by mass, and the charge amount when shaken for 60 seconds under the same shaking condition as described above is (Q2). ).

  The blow-off triboelectric charge amount was measured according to the following procedure using the apparatus shown in FIG.

A metal measurement container 51 (inner diameter: 40 mm, height: 35 mm) having a 500 mesh screen 52 at the bottom is charged with 0.3 g of the measurement sample shaken by the shaker, and a metal lid 53 is formed. . The mass of the entire measurement container 51 at this time is weighed and is set to W1 g. Next, in a suction machine (at least a part in contact with the measurement container 51) is sucked from the suction port 56 and the air volume control valve 55 is adjusted to set the pressure of the vacuum gauge 54 to 2 kPa. In this state, suction is performed for 2 minutes to remove the toner by suction. The potential of the electrometer 58 at this time is set to V (volt). Here, 57 is a capacitor, and the capacity is C (μF). Moreover, the mass of the whole measuring machine after suction is weighed and is defined as W2 (g). The triboelectric charge amount (μC / g or mC / kg) of this sample is calculated as follows.
Frictional charge amount = CV / (W1-W2)

  The charge amount of the toner can be controlled by the type and amount of the charge control agent added to the toner particles, the presence state, and the type and amount of the external additive.

  The toner of the present invention preferably has a weight average particle diameter of 5.0 μm to 12.0 μm and an average circularity of 0.940 to 0.995.

  If the weight average particle diameter is less than 5.0 μm, it is easily influenced by environmental characteristics, and is inferior in density stability and durable image quality. On the other hand, when the weight average particle diameter exceeds 12.0 μm, dot reproducibility and fogging are deteriorated, which is not preferable.

  When the average circularity of the toner of the present invention is less than 0.940, it is not preferable because the circulation property of the toner throughout the durability may not be stable. On the other hand, if the average circularity of the toner exceeds 0.995, the difference in charge amount between the new and old toners may become large especially when the durability is advanced in a low-temperature and low-humidity environment. The frequency increases, which is not preferable.

  The toner particle size distribution and average circularity can be controlled to a desired value by using a conventionally known toner particle production method, classification operation, spheroidization treatment, and the like.

  The weight average particle diameter and number average particle diameter of the toner of the present invention can be measured by various methods such as Coulter Counter TA-II type or Coulter Multisizer (manufactured by Coulter Co.). Specifically, it can be measured as follows. Using a Coulter Multisizer (manufactured by Coulter), an interface (manufactured by Nikka) and a PC9801 personal computer (manufactured by NEC) that output number distribution and volume distribution are connected, and the electrolyte is 1% NaCl using first grade sodium chloride. Adjust the aqueous solution. For example, ISOTON R-II (manufactured by Coulter Scientific Japan) can be used. The measurement procedure is as follows. 100 to 150 ml of the electrolytic aqueous solution is added, and 2 to 20 mg of a measurement sample is further added. The electrolyte in which the sample is suspended is dispersed for about 1 to 3 minutes using an ultrasonic disperser, and the volume distribution is determined by measuring the volume and number of toner particles of 2 μm or more using the Coulter Multisizer with a 100 μm aperture. And the number distribution. Then, the volume-based weight average particle diameter (D4) obtained from the volume distribution according to the present invention and the number-based average particle diameter obtained from the number distribution, that is, the number average particle diameter (D1) are obtained.

  In the present invention, the equivalent-circle diameter, circularity, and frequency distribution of the toner are used as a simple method for quantitatively expressing the shape of the toner particles. In this invention, it measured using the flow type particle image measuring apparatus "FPIA-3000 type" (made by Toa Medical Electronics Co., Ltd.), and computed using the following formula.

  Here, the “particle projected area” is the area of the binarized toner particle image, and the “peripheral length of the particle projected image” is the length of the contour line obtained by connecting the edge points of the toner particle image. Define.

  The circularity in the present invention is an index indicating the degree of unevenness of the toner, and is 1.000 when the toner is a perfect sphere. The more complicated the surface shape, the smaller the circularity.

  In the present invention, the circle-equivalent number average diameter D1 (μm) and the particle size standard deviation SDd, which mean the average value of the particle number frequency distribution based on the number of toners, are the particle size (central value) at the dividing point i of the particle size distribution. Is di, and the frequency is fi.

  As a specific measuring method, 10 ml of ion-exchanged water from which impure solids have been removed in advance is prepared in a container, and a surfactant, preferably an alkylbenzene sulfonate, is added as a dispersant therein, followed by further measurement. Add 0.02 g of sample and disperse uniformly. As a means for dispersion, an ultrasonic disperser “UH-50 type” (manufactured by SMT Co., Ltd.) equipped with a 5φ titanium alloy chip as a vibrator is used, and a dispersion for measurement is performed using a dispersion treatment for 5 minutes. To do. In that case, it cools suitably so that the temperature of this dispersion may not be 40 degreeC or more.

  To measure the shape of the toner, the flow type particle image measuring device is used, and the concentration of the dispersion is readjusted so that the toner particle concentration at the time of measurement is 3000 to 10,000 particles / μl. measure. After the measurement, using this data, the equivalent circle diameter of the toner, the circularity frequency distribution, and the like are obtained.

  The toner of the present invention preferably contains 3 to 20 parts by mass of a release agent with respect to 100 parts by mass of the binder resin constituting the toner. The addition of a release agent to the toner is originally intended to impart functionality in the fixing process. However, in the present invention, in addition to imparting the functionality of the fixing step, it also has a function of controlling toner transportability and circulation characteristics. According to the study by the present inventors, it has been found that the method of adding a release agent to the toner particles can greatly change the slipperiness and aggregation of the toner surface. Therefore, by controlling the presence state of the release agent in the toner particles, it is possible to achieve transportability and circulation properties suitable for the present invention.

  When the addition amount of the release agent is less than 3 parts by mass, it becomes difficult to control the particle behavior of cohesiveness and transportability. On the other hand, if the addition amount of the release agent exceeds 20 parts by mass, the presence state of the release agent in the toner particles cannot be controlled, and the presence of a large amount of the release agent on the surface of the toner particles increases the cohesion and quick friction. Charge is inhibited. For this reason, the fog in a high temperature and high humidity environment deteriorates, which is not preferable.

  The endothermic peak in the differential thermal analysis of the release agent is preferably 50 ° C. to 120 ° C. in terms of controlling the fixing property and the agglomeration characteristics, more preferably 55 ° C. to 100 ° C., and still more preferably 60 ° C. ° C to 90 ° C.

  Further, the developer of the present invention preferably contains two or more types of release agents having different melting points in order to control the fixing property, the cohesiveness and the charging property in a balanced manner.

  In the present invention, the half-value width of the endothermic peak corresponding to the release agent in the differential thermal analysis is more preferably 8 ° C. or less, and further preferably 5 ° C. or less. If the full width at half maximum exceeds 8 ° C, the low molecular weight component contained in the release agent tends to migrate to the toner particle surface due to environmental fluctuations or stress in the developing device. It may increase, leading to a decrease in image quality.

  The half-value width of the endothermic peak referred to here is the temperature width of the endothermic chart that is a half of the peak height from the base line in the endothermic peak.

  As the release agent usable in the toner according to the present invention, petroleum wax such as paraffin wax, microcrystalline wax, petrolactam and derivatives thereof, montan wax and derivatives thereof, hydrocarbon wax and derivatives thereof by Fischer-Tropsch method, Polyolefin waxes represented by polyethylene and derivatives thereof, natural waxes such as carnauba wax and candelilla wax, and derivatives thereof. These derivatives include oxides, block copolymers with vinyl monomers, and graft modified products. Furthermore, higher fatty alcohols, fatty acids such as stearic acid and palmitic acid, or compounds thereof, acid amide waxes, ester waxes, ketones, hydrogenated castor oil and derivatives thereof, plant waxes, animal waxes and the like can be mentioned.

  The maximum endothermic peak temperature of the wax component is measured according to “ASTM D 3418-82”. For the measurement, for example, DSC-7 manufactured by PerkinElmer is used. The temperature correction of the device detection unit uses the melting points of indium and zinc, and the correction of heat uses the heat of fusion of indium. An aluminum pan is used as a measurement sample, an empty pan is set as a control, and measurement is performed at a heating rate of 10 ° C./min.

  In the toner of the present invention, in order to control the presence state of the release agent in the toner particles, there are a method of devising a dispersion state in the resin in the step of adding the release agent, a method of adding a dispersion aid, and the like. Can be mentioned. Further, the state of the release agent on the toner surface can be changed by controlling the temperature in the drying step or heat treatment step after the toner is formed.

  In particular, when the toner of the present invention is produced by a suspension polymerization method, by controlling the polymerization temperature and polymerization time in the polymerization process, the release agent to be sealed inside is precipitated by phase separation to promote encapsulation. Can do. In addition, the surface of the release agent can be controlled by increasing the amount of the release agent surface by controlling the distillation process or by cooling at the end of the polymerization reaction to control the release agent surface growth. This is preferable.

The toner of the present invention contains 1.0 to 2.0 parts by mass of silica fine particles having an average primary particle diameter of 5 nm to 40 nm, and the toner has a BET specific surface area of 1.5 to 3.0 m ² / g. preferable. When silica fine particles having an average primary particle size of less than 5 nm are added, it is not preferable because the silica fine particles are easily embedded in the toner particles by repeating the durability, and the deterioration of the image quality accompanying the toner deterioration is promoted. On the other hand, when silica fine particles having an average primary particle larger than 40 nm are added, the amount of silica fine particles released tends to increase with the endurance, so that the difference in physical properties between the durable toner and the replenishing toner tends to increase in the latter half of the durability. It leads to deterioration and is not preferable.

If the BET specific surface area of the toner of the present invention is less than 1.5 m ² / g, the amount of an external additive or the like that coats the surface of the toner particles is small, and the durability is not preferable. On the other hand, if it is larger than 3.0 m ² / g, there is a tendency that the amount of change in the physical properties of the toner accompanying the endurance tends to increase, and the occurrence frequency of image defects increases, which is not preferable.

Examples of silica fine particles include both the so-called dry method produced by vapor phase oxidation of silicon halides or dry silica called fumed silica, and so-called wet silica produced from water glass or the like. Is possible. Dry silica is preferred because it has less silanol groups on the surface and in the silica fine powder and less production residue such as Na ₂ O, SO ₃ ^2- . In dry silica, it is also possible to obtain composite fine powders of silica and other metal oxides by using other metal halogen compounds such as aluminum chloride and titanium chloride together with silicon halogen compounds in the production process. Is also included.

  The silica fine particles are also preferably imparted with functions such as adjustment of the toner charge amount and improvement of environmental stability by a treatment such as hydrophobization.

  As the hydrophobization treatment agent for silica fine particles, treatment agents such as silicone varnish, various modified silicone varnishes, silicone oil, various modified silicone oils, silane compounds, silane coupling agents, other organic silicon compounds, and organic titanium compounds may be used alone or You may process together.

  The average primary particle size of the silica fine particles is a photograph of the toner magnified by a scanning electron microscope, and further contrasted with a photograph of the toner mapped with Si element by means of elemental analysis means such as XMA attached to the scanning electron microscope. However, it can be measured by measuring 100 or more primary particles of silica fine particles adhering to or separating from the toner particle surface and determining the number average diameter.

  The content of silica fine particles can be quantified using a calibration curve prepared from a standard sample using fluorescent X-ray analysis.

  The BET specific surface area of the toner is measured using a known device such as a degassing device Bacuprep 061 (manufactured by Micromesotic) or a BET measuring device Gemini 2375 (manufactured by Micromesolytic). The BET specific surface area in the present invention is a value of a multipoint BET specific surface area. Specifically, the procedure is as follows.

  After the weight of the empty sample cell is measured, the sample to be measured is filled so as to fall between 0.01 and 0.002 g. Further, the sample cell filled with the sample is set in the degassing apparatus, and degassing is performed at room temperature for 3 hours. After completion of degassing, the mass of the entire sample cell is measured, and the accurate mass of the sample is calculated from the difference from the empty sample cell. Next, empty sample cells are set in the balance port and analysis port of the BET measuring apparatus. A dewar bottle containing liquid nitrogen is set at a predetermined position, and P0 is measured by a saturated vapor pressure (P0) measurement command. After completing the P0 measurement, the sample cell prepared for degassing is set in the analysis port, and after inputting the sample mass and P0, the measurement is started by the BET measurement command. After that, the BET specific surface area is automatically calculated.

  The toner of the present invention preferably uses a charge control agent in order to obtain stable image characteristics over a long period of time.

  In a more preferable embodiment of the present invention, it is desirable to contain a charge control agent and a charge control resin in order to perform control so that stable charging ability can be exhibited over a long period of time.

  The charge control agent has excellent characteristics of charge rise, while the charge control resin can maintain a constant charge amount and has excellent durability and environmental stability. By using together, it becomes easy to control the charge amount within a desired range.

  Further, since the control of the charge amount of the developer and the control of the electrostatic cohesive force are closely related, it is an important factor in controlling the static and dynamic bulk density of the toner in the present invention.

  As the charge control agent for controlling the developer to be negatively charged, for example, organometallic compounds and chelate compounds are effective. There are monoazo metal compounds, acetylacetone metal compounds, aromatic oxycarboxylic acids, aromatic dicarboxylic acids, oxycarboxylic acids, and dicarboxylic acid-based metal compounds. Others include aromatic oxycarboxylic acids, aromatic mono- and polycarboxylic acids and their metal salts, anhydrides, esters, phenol derivatives such as bisphenol, and the like. Furthermore, urea derivatives, metal-containing salicylic acid compounds, metal-containing naphthoic acid compounds, boron compounds, quaternary ammonium salts, calixarene and the like can be mentioned. These can be used alone or in combination of two or more.

  Examples of the charge control agent for controlling the developer to be positively charged include nigrosine-modified products such as nigrosine and fatty acid metal salts, guanidine compounds, imidazole compounds, tributylbenzylammonium-1-hydroxy-4-naphthosulfonate, tetra Quaternary ammonium salts such as butylammonium tetrafluoroborate, and onium salts such as phosphonium salts thereof and their analogs, lake pigments thereof, triphenylmethane dyes and lake lakes thereof (as rake agents include phosphotungstic acid Phosphomolybdic acid, phosphotungstic molybdic acid, tannic acid, lauric acid, gallic acid, ferricyanide, ferrocyanide, etc.), metal salts of higher fatty acids; dibutyltin oxide, dioctyltin oxide, dicyclohexyltin Diorganotin oxides such as side; dibutyl tin borate, dioctyl tin borate, diorgano tin borate, and the like, such as dicyclohexyl tin borate, and the like. These can be used alone or in combination of two or more.

  The amount of charge control agent used varies depending on the type of charge control agent used, but is preferably 0.01 to 20 parts by mass, and 0.1 to 10 parts by mass per 100 parts by mass of the binder resin. More preferred. The charge control agent may be blended (internally added) to the toner particles, or may be mixed (externally added) with the toner particles.

  Examples of the charge control resin for controlling the developer to be negatively charged include a polymer compound having a sulfonic acid group in the side chain, and in particular, a methacrylic acid monomer containing a sulfonic acid group has a copolymerization ratio of 2 mass. % Or more, preferably 4% by mass or more, and using a polymer compound comprising a styrene and / or styrene (meth) acrylate copolymer having a glass transition temperature (Tg) of 45 to 90 ° C., It is particularly preferable because the charging characteristics and the aggregation characteristics can be suitably controlled.

  As said sulfonic acid group containing (meth) acrylamide type monomer, what can be represented by following General formula (1) is preferable, and, specifically, 2-acrylamide-2-methylpropanesulfonic acid and 2-methacrylamide-2- Examples thereof include methyl propane sulfonic acid.

［上記一般式（１）中、Ｒ₁は水素原子、又はメチル基を示し、Ｒ₂とＲ₃は、それぞれ水素原子、Ｃ１乃至Ｃ１０のアルキル基、アルケニル基、アリール基、又はアルコキシ基を示し、ｎは１乃至１０の整数を示す。］

[In the general formula (1), R ₁ represents a hydrogen atom or a methyl group, and R ₂ and R ₃ represent a hydrogen atom, a C1 to C10 alkyl group, an alkenyl group, an aryl group, or an alkoxy group, respectively. , N represents an integer of 1 to 10. ]

  Examples of the charge control resin for controlling the developer to be positively charged include a polymer compound having a quaternary ammonium salt in the side chain.

  These charge control resins are contained in the toner particles in an amount of 0.05 to 20 parts by mass, and more preferably 0.1 to 10 parts by mass, with respect to 100 parts by mass of the binder resin, so that desired charge amount and cohesiveness can be obtained. Is obtained.

  The toner particles of the present invention are preferably particles obtained by a polymerization method in order to achieve uniform spheroidization and multi-functionality. The toner according to the present invention can also be produced by a pulverization method. However, toner particles obtained by this pulverization method are generally amorphous, and the average circularity which is a preferable requirement of the present invention is 0.940. In order to obtain the above physical properties, it is necessary to perform mechanical / thermal or some special treatment.

  Examples of the toner polymerization method include a direct polymerization method, a suspension polymerization method, an emulsion polymerization method, an emulsion association polymerization method, and a seed polymerization method. Among these, the balance between the particle size and the particle shape is easy to balance. In this respect, it is particularly preferable to produce the suspension by a suspension polymerization method. In this suspension polymerization method, a monomer composition is prepared by uniformly dissolving or dispersing a polymerizable monomer and a colorant (and, if necessary, a polymerization initiator, a crosslinking agent, a charge control agent, and other additives). After that, the monomer composition is dispersed in a continuous layer containing a dispersion stabilizer (for example, an aqueous phase) using a suitable stirrer and simultaneously subjected to a polymerization reaction to obtain a toner having a desired particle size. To get. The toner obtained by this suspension polymerization method (hereinafter referred to as polymerized toner) is easy to obtain a toner having a high average circularity because the individual toner particle shapes are almost spherical, and the toner has a charge amount of Has a relatively uniform distribution, and thus has high developability and transferability.

  The toner particles of the present invention may contain a colorant in order to impart coloring power. Examples of the organic pigment or organic dye as the colorant preferably used in the present invention include the following.

  As the organic pigment or organic dye as the cyan colorant, a copper phthalocyanine compound and a derivative thereof, an anthraquinone compound, a basic dye lake compound, or the like is used. Specifically, C.I. 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. And CI Pigment Blue 66.

  As organic pigments or organic dyes as magenta colorants, condensed azo compounds, diketopyrrolopyrrole compounds, anthraquinones, quinacridone compounds, basic dye lake compounds, naphthol compounds, benzimidazolone compounds, thioindigo compounds, perylene compounds, etc. are used. It is done. Specifically, C.I. 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. And CI Pigment Red 254.

  As the organic pigment or organic dye as the yellow colorant, compounds represented by condensed azo compounds, isoindolinone compounds, anthraquinone compounds, azo metal complexes, methine compounds, and allylamide compounds are used. Specifically, C.I. 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 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. And CI Pigment Yellow 194.

  These colorants can be used alone or in a mixed state, or in a solid solution state. The colorant is selected from the viewpoints of hue angle, saturation, brightness, light resistance, OHP transparency, and dispersibility in the toner. The addition amount of the colorant is 1 to 20 parts by mass with respect to 100 parts by mass of the binder resin.

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

  When a magnetic material is used as the black colorant, 30 to 200 parts by mass are added to 100 parts by mass of the binder resin, unlike other colorants.

  In the present invention, when toner particles are obtained using a polymerization method, it is necessary to pay attention to the polymerization inhibition property and water phase transfer property of the colorant, and preferably, there is no surface modification, for example, polymerization inhibition. It is better to have a hydrophobic treatment with the substance. In particular, dyes and carbon blacks have many polymerization inhibiting properties, so care must be taken when using them. A preferable method for surface-treating the dye system includes a method in which a polymerizable monomer is polymerized in the presence of these dyes in advance, and the obtained colored polymer is added to the monomer system.

  Carbon black may be treated with a substance that reacts with the surface functional groups of carbon black, such as polyorganosiloxane, in addition to the same treatment as the above dye.

  Next, a method for producing the toner of the present invention by suspension polymerization will be described.

  When the toner of the present invention is produced by the suspension polymerization method, examples of the polymerizable monomer constituting the polymerizable monomer system to be used include the following.

  Examples of the polymerizable monomer include styrene monomers such as styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, p-methoxystyrene, p-ethylstyrene, methyl acrylate, ethyl acrylate, Acrylic esters such as n-butyl acrylate, isobutyl acrylate, n-propyl acrylate, n-octyl acrylate, dodecyl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, 2-chloroethyl acrylate, phenyl acrylate, etc. , Methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-octyl methacrylate, dodecyl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate, phenyl methacrylate, Methacrylic acid dimethyl aminoethyl methacrylate esters such as diethylaminoethyl methacrylate and other acrylonitrile-methacrylonitrile-monomer acrylamide.

  These monomers can be used alone or in combination. Among the above-mentioned monomers, styrene or a styrene derivative is preferably used alone or mixed with other monomers from the viewpoint of the developing characteristics and durability of the toner.

  In the production of the polymerized toner according to the present invention, a resin may be added to the monomer system for polymerization.

  For example, a monomer containing a hydrophilic functional group such as an amino group, a carboxylic acid group, a hydroxyl group, a glycidyl group, or a nitrile group that cannot be used because it is soluble in an aqueous suspension and causes emulsion polymerization by dissolving in an aqueous suspension. When it is desired to introduce a body component into the toner, a random copolymer of these with a vinyl compound such as styrene or ethylene, a block copolymer, a graft copolymer, or the like, or in the form of a copolymer, or polyester, polyamide, etc. It can be used in the form of a polyaddition polymer such as a polycondensate, a polyether or a polyimine. When such a polymer containing a polar functional group is allowed to coexist in the toner, the above-mentioned wax component is phase-separated and the encapsulation becomes stronger, and a toner having good offset resistance, blocking resistance, and low-temperature fixability can be obtained. Obtainable.

  Further, a resin other than the above may be added to the monomer system for the purpose of improving the dispersibility and fixing properties of the material or the image characteristics. Examples of the resin used include homopolymers of styrene such as polystyrene and polyvinyltoluene and substituted products thereof; styrene-propylene copolymer, styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, styrene-acrylic. Acid methyl copolymer, styrene-ethyl acrylate copolymer, styrene-butyl acrylate copolymer, styrene-octyl acrylate copolymer, styrene-dimethylaminoethyl acrylate copolymer, styrene-methyl methacrylate copolymer Polymer, styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate copolymer, styrene-dimethylaminoethyl methacrylate copolymer, styrene-vinyl methyl ether copolymer, styrene-vinyl ethyl ether copolymer, Styrene-vinyl methyl Styrene copolymers such as ketone copolymers, styrene-butadiene copolymers, styrene-isoprene copolymers, styrene-maleic acid copolymers, styrene-maleic acid ester copolymers; polymethyl methacrylate, polybutyl methacrylate , Polyvinyl acetate, polyethylene, polypropylene, polyvinyl butyral, silicone resin, polyester resin, polyamide resin, epoxy resin, polyacrylic acid resin, rosin, modified rosin, terpene resin, phenol resin, aliphatic or alicyclic hydrocarbon resin, Aromatic petroleum resins can be used alone or in combination.

  The addition amount of these resins is preferably 1 to 20 parts by mass with respect to 100 parts by mass of the monomer. If the amount is less than 1 part by mass, the effect of addition is small. On the other hand, if it exceeds 20 parts by mass, the balance between the physical properties and the production stability of the polymerized toner is not preferred.

  Furthermore, if a polymer having a molecular weight different from the molecular weight range of the toner obtained by polymerizing the monomer is dissolved in the monomer and polymerized, a toner having a wide molecular weight distribution and high offset resistance can be obtained. it can.

  The polymerization initiator used in the production of the polymerized toner according to the present invention has a half-life of 0.5 to 30 hours during the polymerization reaction, and is 0.5 to 20 masses per 100 mass parts of the polymerizable monomer. When the polymerization reaction is carried out with a part addition amount, a polymer having a maximum between 10,000 and 100,000 in molecular weight can be obtained, and the toner can be provided with desirable strength and suitable melting characteristics. Examples of polymerization initiators include 2,2′-azobis- (2,4-dimethylvaleronitrile), 2,2′-azobisisobutyronitrile, 1,1′-azobis (cyclohexane-1-carbonitrile) Azo or diazo polymerization initiators such as 2,2′-azobis-4-methoxy-2,4-dimethylvaleronitrile, azobisisobutyronitrile; benzoyl peroxide, t-butylperoxy 2-ethylhexa Noate, t-butyl peroxypivalate, t-butyl peroxyisobutyrate, t-butyl peroxyneodecanoate, methyl ethyl ketone peroxide, diisopropyl peroxycarbonate, cumene hydroperoxide, 2,4-dichlorobenzoyl Peroxide polymerization such as peroxide and lauroyl peroxide Agents.

  When the polymerized toner according to the present invention is produced, a crosslinking agent may be added, and a preferable addition amount is 0.001 to 15% by mass.

  In producing the polymerized toner according to the present invention, a molecular weight modifier can be used. Examples of the molecular weight modifier include mercaptans such as t-dodecyl mercaptan, n-dodecyl mercaptan, and n-octyl mercaptan; halogenated hydrocarbons such as carbon tetrachloride and carbon tetrabromide; α-methylstyrene dimer, and the like. Can be mentioned. These molecular weight regulators can be added before the polymerization starts or during the polymerization. The molecular weight modifier is generally used in a proportion of 0.01 to 10 parts by mass, preferably 0.1 to 5 parts by mass, with respect to 100 parts by mass of the polymerizable monomer.

  In the method for producing a polymerized toner according to the present invention, generally, the above-described toner composition, that is, a polymer having a sulfonic acid group in a polymerizable monomer, a release agent, a plasticizer, a charge control agent, a crosslinking agent, The components necessary for the toner, such as colorants, and other additives such as an organic solvent, a high molecular weight polymer, and a dispersant added to reduce the viscosity of the polymer produced by the polymerization reaction are appropriately added, and the homogenizer, ball mill The monomer system uniformly dissolved or dispersed by a dispersing machine such as a colloid mill or an ultrasonic dispersing machine is suspended in an aqueous medium containing a dispersion stabilizer. At this time, the particle size of the obtained toner particles becomes sharper by using a high-speed disperser such as a high-speed stirrer or an ultrasonic disperser to obtain a desired toner particle size at a stretch. 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 being suspended 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.

  After granulation, stirring may be performed using a normal stirrer to such an extent that the particle state is maintained and the particles are prevented from floating and settling.

  When the polymerized toner according to the present invention is produced, a known surfactant or organic or inorganic dispersant can be used as a dispersion stabilizer. Among them, inorganic dispersants are unlikely to produce harmful ultrafine powders, and because of their steric hindrance, dispersion stability is obtained, so even if the reaction temperature is changed, stability is not easily lost, and cleaning is easy and does not adversely affect the toner. Can be preferably used. Examples of such inorganic dispersants include polyvalent metal phosphates such as calcium phosphate, magnesium phosphate, aluminum phosphate and zinc phosphate, carbonates such as calcium carbonate and magnesium carbonate, calcium metasuccinate, calcium sulfate and barium sulfate. Inorganic oxides such as inorganic salts, calcium hydroxide, magnesium hydroxide, aluminum hydroxide, silica, bentonite and alumina can be mentioned.

  These inorganic dispersants may be used alone in an amount of 0.2 to 20 parts by mass with respect to 100 parts by mass of the polymerizable monomer, and 0.001 to 0.1 parts by mass for the purpose of adjusting the particle size distribution. These surfactants may be used in combination. Examples of the surfactant include sodium dodecylbenzene sulfate, sodium tetradecyl sulfate, sodium pentadecyl sulfate, sodium octyl sulfate, sodium oleate, sodium laurate, sodium stearate, potassium stearate and the like.

  When these inorganic dispersants are used, they may be used as they are, but in order to obtain finer particles, the inorganic dispersant particles can be generated in an aqueous medium. For example, in the case of calcium phosphate, a sodium phosphate aqueous solution and a calcium chloride aqueous solution can be mixed with high-speed stirring to produce water-insoluble calcium phosphate, which enables more uniform and fine dispersion. At the same time, water-soluble sodium chloride salt is produced as a by-product. However, if water-soluble salt is present in the aqueous medium, dissolution of the polymerizable monomer in water is suppressed, and ultrafine toner is generated by emulsion polymerization. This is more convenient. Since it becomes an obstacle when removing the remaining polymerizable monomer at the end of the polymerization reaction, it is better to replace the aqueous medium or desalinate with an ion exchange resin. The inorganic dispersant can be almost completely removed by dissolving with an acid or alkali after completion of the polymerization.

  In the polymerization step, the polymerization is performed at a polymerization temperature of 40 ° C. or higher, generally 50 to 90 ° C. In order to consume the remaining polymerizable monomer, it is possible to raise the reaction temperature to 90 to 150 ° C. at the end of the polymerization reaction. The polymerized toner particles are filtered, washed, and dried by a known method after the polymerization is completed, and the toner can be obtained by mixing and adhering the inorganic fine powder to the surface. Moreover, it is also one of desirable forms that a classification process is included in the manufacturing process to cut coarse powder and fine powder.

  When the toner of the present invention is produced by a pulverization method, a known method is used. For example, binder resin, polymer having sulfonic acid group, mold release agent, charge control agent, and sometimes necessary components such as colorant and other additives, etc., and other additives are sufficiently mixed by a mixer such as a Henschel mixer or a ball mill. Then, melt and knead using a heat kneader such as a heating roll, kneader, extruder, etc. to disperse or dissolve other toner materials such as magnetic powder in the resin, and cool and solidify. After pulverization, classification, surface treatment as necessary is performed to obtain toner particles, and the toner of the present invention can be obtained by adding and mixing fine powder as necessary. Either the classification or the surface treatment may be performed first. In the classification step, it is preferable to use a multi-division classifier in terms of production efficiency. The pulverization step can be performed by a method using a known pulverizer such as a mechanical impact type or a jet type. In order to obtain a toner having a specific degree of circularity according to the present invention, it is preferable to further heat and pulverize or to add a mechanical impact as an auxiliary. Further, a hot water bath method in which finely pulverized (classified as necessary) toner particles are dispersed in hot water, a method of passing in a hot air stream, or the like may be used.

  Examples of means for applying mechanical impact force include a method using a mechanical impact type pulverizer such as a kryptron system manufactured by Kawasaki Heavy Industries, Ltd. There is a method of applying a mechanical impact force to the toner by a force such as a compressive force or a frictional force by pressing the toner to the inside of the casing by a centrifugal force with a blade rotating at high speed, as in a device such as a hybridization system manufactured by the manufacturer.

  In the case of using the mechanical impact method, a thermomechanical impact in which the processing temperature is a temperature in the vicinity of the glass transition point Tg (Tg ± 10 ° C.) of the toner is preferable from the viewpoint of preventing aggregation and productivity. More preferably, it is particularly effective to improve the transfer efficiency to carry out at a temperature in the range of the glass transition point Tg ± 5 ° C. of the toner.

  Furthermore, the toner of the present invention is a method for obtaining a spherical toner by atomizing a molten mixture into air using a disk or a multi-fluid nozzle described in JP-B-56-13945, etc. An emulsion polymerization method typified by a dispersion polymerization method for directly producing a toner using an aqueous organic solvent in which the resulting polymer is insoluble or a soap-free polymerization method for producing a toner by directly polymerizing in the presence of a water-soluble polar polymerization initiator, etc. The toner can also be manufactured by a method of manufacturing the toner used.

  As the binder resin when the toner of the present invention is produced by a pulverization method, styrene such as polystyrene and polyvinyltoluene, and a homopolymer of a substituted product thereof; styrene-propylene copolymer, styrene-vinyltoluene copolymer, styrene -Vinylnaphthalene copolymer, styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer, styrene-butyl acrylate copolymer, styrene-octyl acrylate copolymer, styrene-dimethylaminoethyl acrylate Copolymer, styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate copolymer, styrene-dimethylaminoethyl methacrylate copolymer, styrene-vinyl methyl ether copolymer Styrene-vinyl ethyl ether Polystyrene, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-maleic acid copolymer, styrene-maleic acid ester copolymer, etc .; poly Methyl methacrylate, polybutyl methacrylate, polyvinyl acetate, polyethylene, polypropylene, polyvinyl butyral, silicone resin, polyester resin, polyamide resin, epoxy resin, polyacrylic resin, rosin, modified rosin, terpene resin, phenol resin, aliphatic or fat Cyclic hydrocarbon resins, aromatic petroleum resins, paraffin wax, carnauba wax and the like can be used alone or in combination. In particular, a styrene copolymer and a polyester resin are preferable in terms of development characteristics, fixing properties, and the like.

  The developer of the present invention is a silica of 5 to 40 nm, which is a more preferable form, for the purpose of highly controlling the bulk density and charge amount and for the purpose of protecting the toner particle surface and suppressing the deterioration of the developer due to durability. It is preferable to add inorganic fine powder in addition to the addition of fine particles.

  In order to obtain the bulk density characteristics and charging characteristics of the developer required in the present invention, it is necessary to control to some extent with the toner particles, but it is highly dependent on the type, amount and formulation of the inorganic fine powder covering the toner particle surface. Can be controlled.

  As the inorganic fine powder added to the toner of the present invention, composite oxides such as silica, alumina, titania and hydrotalcite can be used.

  The average primary particle diameter of the inorganic fine powder is generally from the viewpoint of imparting functionality by adding a plurality of arbitrary particles having a particle size of 4 to 700 nm. The total amount of the toner particles is 0.1 to 4% by mass. This is a preferred mode of use in which the bulk density and charging characteristics can be controlled uniformly.

  More preferably, main silica fine particles of 5 to 40 nm are added in an amount of 1.0 to 2.0 parts by mass with respect to 100 parts by mass of toner particles, and an arbitrary particle size is used for the purpose of more precisely controlling fluidity and chargeability. It is preferable to add other fine powders having

Examples of silica include both the so-called dry process produced by vapor phase oxidation of silicon halides or dry silica called fumed silica, and so-called wet silica produced from water glass and the like. It is. Dry silica is preferred because it has less silanol groups on the surface and in the silica fine powder and less production residue such as Na ₂ O, SO ₃ ^2- . In dry silica, it is also possible to obtain composite fine powders of silica and other metal oxides by using other metal halogen compounds such as aluminum chloride and titanium chloride together with silicon halogen compounds in the production process. Is also included.

In particular, for the purpose of adjusting the bulk density, which is an important parameter in the present invention, the average primary particle diameter exceeds 30 nm (preferably the specific surface area is less than 50 m ² / g), more preferably the primary particle diameter is 50 nm or more (preferably the ratio). It is also one of preferable modes to further add inorganic or organic fine particles having a surface area of less than 30 m ² / g). For example, hydrotalcite, titanium oxide, alumina, spherical silica particles, spherical polymethylsilsesquioxane particles, spherical resin particles and the like are preferably used.

  The inorganic fine powder is also preferably imparted with functions such as adjustment of the charge amount of the developer and improvement of environmental stability by a treatment such as hydrophobization.

  As the hydrophobic treatment agent for inorganic fine powder, treatment agents such as silicone varnish, various modified silicone varnishes, silicone oil, various modified silicone oils, silane compounds, silane coupling agents, other organic silicon compounds, and organic titanium compounds can be used alone. Or you may process together.

  The average primary particle size of the inorganic fine powder is a photograph of the toner magnified by a scanning electron microscope, and is further mapped by the element contained in the inorganic fine powder by an elemental analysis means such as XMA attached to the scanning electron microscope. In comparison with the photograph of the toner, 100 or more primary particles of the inorganic fine powder adhered to or released from the surface of the toner particles are measured, and the number average diameter is obtained.

  The content of the inorganic fine powder can be quantified using a calibration curve prepared from a standard sample using fluorescent X-ray analysis.

  The developer used in the present invention may further contain other additives, for example, a lubricant powder such as a polyfluorinated ethylene powder, a zinc stearate powder, a polyvinylidene fluoride powder, or a cerium oxide powder within a range that does not substantially adversely affect the developer. Abrasives such as silicon carbide powder and strontium titanate powder; anti-caking agents; and organic fine particles and inorganic fine particles of opposite polarity can be used in small amounts as a developability improver. These additives can also be used after hydrophobizing the surface.

  Hereinafter, the present invention will be specifically described with reference to production examples and examples, but this does not limit the present invention in any way. In addition, all the parts in the following mixing | blending are a mass part.

(Production example of charge control resin A)
In a pressurizable reaction vessel equipped with a reflux tube, a stirrer, a thermometer, a nitrogen introduction tube, a dropping device and a decompression device, 250 parts of methanol as a solvent, 150 parts of 2-butanone and 100 parts of 2-propanol, styrene as a monomer 83 parts, 10 parts of 2-ethylhexyl acrylate, and 7 parts of 2-acrylamido-2-methylpropanesulfonic acid were added and heated to reflux temperature with stirring. A solution obtained by diluting 1 part of t-butylperoxy-2-ethylhexanoate as a polymerization initiator with 20 parts of 2-butanone was added dropwise over 30 minutes, and stirring was continued for 5 hours. Further, t-butylperoxy-2 was further added. -A solution obtained by diluting 1 part of ethylhexanoate with 20 parts of 2-butanone was added dropwise over 30 minutes, and the mixture was further stirred for 5 hours to complete the polymerization. Further, 500 parts of deionized water was added while maintaining the temperature, and after stirring for 2 hours at 80 to 100 revolutions per minute so as not to disturb the interface between the organic layer and the aqueous layer, the mixture was allowed to stand for 30 minutes and separated. The aqueous layer was discarded, and anhydrous sodium sulfate was added to the organic layer for dehydration.

  Next, the polymer obtained after the polymerization solvent was distilled off under reduced pressure was coarsely pulverized to 100 μm or less using a cutter mill equipped with a 150 mesh screen. The obtained sulfur-containing polymer had a weight average molecular weight of Mw = 28000 and Tg of about 76 ° C. The obtained sulfur-containing polymer is designated as charge control resin A.

[Toner Production Example 1]
360 parts of ion-exchanged water was charged with 0.1M-Na ₃ PO ₄ aqueous solution 440 parts, followed by heating to 59 ° C., using a TK-type homomixer (manufactured by Tokushu Kika Kogyo) at 12,000rpm Stir. To this, 36 parts of 1.0 M CaCl ₂ aqueous solution was added to obtain an aqueous medium containing calcium phosphate. Further, dilute hydrochloric acid was added to adjust the pH of the aqueous medium to 5.3.

on the other hand,
Styrene 82 parts n-butyl acrylate 18 parts C.I. I. Pigment Blue 15: 3 6.5 parts Charge Control Resin A 1.5 parts Bontron E-88 (manufactured by Orient Chemical Co., Ltd.) 0.5 parts Saturated polyester 10 parts (acid value 10 mgKOH / g, peak molecular weight 11,000) , Tg = 75 ° C.)
Ester wax (endothermic peak = 72 ° C., half-value width = 4 ° C.) 5 parts hydrocarbon wax (endothermic peak = 78 ° C., half-value width = 2 ° C.) 5 parts divinylbenzene 0.02 part The above formulation was heated to 59 ° C. The solution was uniformly dissolved and dispersed at 6000 rpm using a TK homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.). To this, 4.0 parts of a polymerization initiator 2,2′-azobis (2,4-dimethylvaleronitrile) was dissolved to prepare a polymerizable monomer composition.

The polymerizable monomer composition is put into the aqueous medium, and stirred at 12,000 rpm with a TK homomixer in an N ₂ atmosphere at an internal temperature of 59 ° C. to prepare the polymerizable monomer composition. Grained.

  Thereafter, while stirring with a paddle stirring blade, NaOH was added to adjust the pH to 9 when 6 hours passed, and then the temperature was raised to 80 ° C. at a temperature rising rate of 40 ° C./h, and the reaction was allowed to proceed for 5 hours. After the completion of the polymerization reaction, the residual monomer was distilled off under reduced pressure, and the mixture was held at 90 ° C. for 1 hour, then rapidly cooled at a temperature decrease rate of 120 ° C./h, and left still for 10 hours. After standing, the supernatant was removed so that the solid concentration was 35%, thereby removing suspended matters in the slurry. Hydrochloric acid was added to adjust the pH to 1.2, and the calcium phosphate salt was dissolved by stirring for 3 hours.

  Thereafter, filtration, washing with ion-exchanged water, and drying at 40 ° C. for 10 hours were performed to obtain toner particles (1) having a weight average particle diameter of 6.5 μm.

  100 parts of the toner particles (1) and 1.7 parts of a hydrophobic silica fine powder having an average primary particle diameter of 7 nm treated with hexamethyldisilazane and then with silicone oil were added to a V-type mixer V-60 ((Co., Ltd.). ) Manufactured by Deoksugaku Kosaku) p. m. For 3 minutes.

  Next, the above premix is introduced into a Henschel mixer FM-75 type (made by Mitsui Miike Chemical Co., Ltd.) shown in FIG. 14, and the baffle plate angle is adjusted to be parallel to the inner diameter tangent of the Henschel mixer. The mixture was mixed for 2 minutes under the condition of a peripheral speed of 20 m / s. Thereafter, the angle of the baffle plate was adjusted to be perpendicular to the inner diameter tangent of the Henschel mixer, and the peripheral speed was increased to 30 m / s and mixed for 1 minute.

  Subsequently, 0.08 part of hydrotalcite having an average primary particle size of 400 nm was introduced into the system and mixed for 1 minute under the same conditions to obtain the toner (1) of the present invention.

  The average circularity of toner (1) was 0.980.

  Table 1 shows the physical property values of the toner.

[Toner Production Example 2]
In Toner Production Example 1, 1.1 parts of hydrophobic silica fine powder having an average primary particle diameter of 35 nm was obtained by changing the dispersant concentration of the aqueous medium containing calcium phosphate salt and treating the silica fine particles to be added with hexamethyldisilazane. A toner (2) having a weight average particle diameter of 7.8 μm and an average circularity of 0.978 was obtained in the same manner except for the change. Table 1 shows the physical properties of the obtained toner.

[Toner Production Example 3]
In the same manner as in Toner Production Example 1, except that the concentration of the dispersant in the aqueous medium containing the calcium phosphate salt was changed and the amount of the fine silica powder to be added was changed to 1.9 parts, the weight average particle size was 5.2 μm. A toner (3) having an average circularity of 0.983 was obtained. Table 1 shows the physical properties of the obtained toner.

[Toner Production Example 4]
In the same manner as in Toner Production Example 1, except that the concentration of the dispersant in the aqueous medium containing calcium phosphate salt was changed, toner particles (4) having a weight average particle diameter of 13.0 μm were obtained.

  To 100 parts of the toner particles (4), 0.9 part of hydrophobic silica fine powder having an average primary particle diameter of 50 nm treated with hexamethyldisilazane and 0.08 part of hydrotalcite having an average primary particle diameter of 400 nm are used. Was put directly into the Henschel mixer without the premixing step. The angle of the baffle plate was adjusted to be perpendicular to the inner diameter tangent of the Henschel mixer, and dry mixing for 3 minutes was repeated twice under the condition of a peripheral speed of 30 m / s to obtain the toner (4) of the present invention.

  The average circularity of toner (4) was 0.975.

  Table 1 shows the physical property values of the obtained toner.

[Toner Production Example 5]
In the same manner as in Toner Production Example 4, except that the concentration of the dispersant in the aqueous medium containing calcium phosphate salt was changed and the amount of the fine silica powder to be added was changed to 2.2 parts, the weight average particle size was 5.5 μm. A toner (5) having an average circularity of 0.987 was obtained. Table 1 shows the physical properties of the obtained toner.

[Toner Production Example 6]
80 parts of styrene / n-butyl acrylate copolymer (mass ratio 80/20) (Mn = 24300 Mw / Mn = 3.0)
20 parts of saturated polyester (acid value 10 mg KOH / g, peak molecular weight 11,000, Tg = 75 ° C.)
Bontron E-88 (manufactured by Orient Chemical Co., Ltd.) 3 parts C.I. I. Pigment Blue 15: 3 6.5 parts ester wax (endothermic peak = 72 ° C., half-value width = 4 ° C.) 5 parts The above materials are mixed in a blender, melt-kneaded in a biaxial extruder heated to 110 ° C., and cooled. The kneaded product is coarsely pulverized with a hammer mill, the coarsely pulverized product is finely pulverized with a turbo mill (manufactured by Turbo Kogyo Co., Ltd.), and the resulting finely pulverized product is air-classified to produce toner particles (6 )

  Next, 100 parts of the toner particles (6) obtained and 1.7 parts of hydrophobic silica fine powder having an average primary particle diameter of 12 nm treated with silicone oil were mixed with a V-type mixer V-60 (Tokujukaku Co., Ltd.). At a rotational speed of 26 r. p. m. For 3 minutes.

  Next, the premix was introduced into a Henschel mixer, the angle of the baffle plate was adjusted to be parallel to the inner diameter tangent of the Henschel mixer, and the mixture was mixed for 2 minutes at a peripheral speed of 20 m / s. Thereafter, the angle of the baffle plate was adjusted to be perpendicular to the inner diameter tangent of the Henschel mixer, and the peripheral speed was increased to 30 m / s and mixed for 1 minute.

  Subsequently, 0.08 part of alumina AA03 (manufactured by Sumitomo Chemical Co., Ltd.) having an average primary particle size of 300 nm was charged into the system and mixed for 1 minute under the same conditions to obtain toner (6) of the present invention.

  The average circularity of toner (6) was 0.930.

  Table 1 shows the physical property values of the toner.

[Toner Production Example 7]
In Toner Production Example 1, the holding process of 1 hour at 90 ° C. was changed to 3 hours at 95 ° C., and the hydrotalcite added in the external addition step was alumina AA03 (Sumitomo Chemical Co., Ltd.) having an average primary particle size of 300 nm. A toner (7) having a weight average particle size of 6.5 μm and an average circularity of 0.997 was obtained in the same manner except that the product was changed to “manufactured”. Table 1 shows the physical properties of the obtained toner.

[Toner Production Example 8]
In toner production example 1, the amount of ester wax added was changed to 4 parts, the hydrocarbon wax was not added, and the hydrotalcite added in the external addition step was changed to titanium oxide having an average primary particle size of 270 nm. In the same manner, a toner (8) having a weight average particle size of 6.5 μm and an average circularity of 0.983 was obtained. Table 1 shows the physical properties of the obtained toner.

[Toner Production Example 9]
In Toner Production Example 1, the amount of ester wax added was changed to 9 parts, the amount of hydrocarbon wax added was changed to 11 parts, and hydrotalcite added in the external addition step was oxidized with an average primary particle size of 270 nm. A toner (9) having a weight average particle size of 6.5 μm and an average circularity of 0.975 was obtained in the same manner except that the material was changed to titanium. Table 1 shows the physical properties of the obtained toner.

[Toner Production Example 10]
A toner having a weight average particle diameter of 6.5 μm and an average circularity of 0.985 in the same manner as in toner production example 1, except that no ester wax is added and the amount of hydrocarbon wax added is changed to 2 parts. (10) was obtained. Table 1 shows the physical properties of the obtained toner.

[Toner Production Example 11]
In Toner Production Example 1, the amount of ester wax added was changed to 10 parts and the amount of hydrocarbon wax added was changed to 12 parts, and after completion of the polymerization reaction, the mixture was allowed to stand for 10 hours without quenching, and the supernatant liquid removing step was performed. A toner (11) having a weight average particle size of 6.5 μm and an average circularity of 0.970 was obtained in the same manner except that the procedure was not performed. Table 1 shows the physical properties of the obtained toner.

[Toner Production Example 12]
In Toner Production Example 1, the weight was kept the same except that the polymerization reaction was allowed to stand for 10 hours without quenching, the supernatant was not removed, and the drying process was changed to 45 ° C. for 5 hours. Toner particles (12) having an average particle diameter of 6.5 μm were obtained.

  With respect to 100 parts of the toner particles (12), 1.7 parts of a hydrophobic silica fine powder having an average primary particle diameter of 7 nm, which has been treated with hexamethyldisilazane and then with silicone oil, and hydrophobized having an average primary particle diameter of 400 nm. 0.08 parts of talcite was directly charged into a Henschel mixer without performing the premixing step. The angle of the baffle plate was adjusted to be perpendicular to the inner diameter tangent of the Henschel mixer, and dry mixing for 3 minutes was repeated twice under the condition of a peripheral speed of 35 m / s to obtain toner (12).

  The average circularity of the toner (12) was 0.983.

  Table 1 shows the physical property values of the obtained toner.

[Toner Production Example 13]
Synthetic condenser tube of toner binder , stirrer, and nitrogen introduction tube, 724 parts of bisphenol A ethylene oxide 2-mole adduct, 276 parts of isophthalic acid and 2 parts of dibutyltin oxide were placed at normal pressure, 230 The mixture was reacted for 8 hours at 0 ° C. and further reacted for 5 hours at a reduced pressure of 10 to 15 mmHg, then cooled to 160 ° C., 32 parts of phthalic anhydride was added thereto and reacted for 2 hours. Subsequently, it cooled to 80 degreeC and reacted with 188 parts of isophorone diisocyanate in ethyl acetate for 2 hours, and the isocyanate containing prepolymer I was obtained. Next, 267 parts of prepolymer I and 14 parts of isophoronediamine were reacted at 50 ° C. for 2 hours to obtain urea-modified polyester I having a weight average molecular weight of 64,000.

  In the same manner as above, 724 parts of bisphenol A ethylene oxide 2-mole adduct and 276 parts of terephthalic acid were polycondensed at 230 ° C. for 8 hours under normal pressure, and then reacted for 5 hours at a reduced pressure of 10 to 15 mmHg to give a peak molecular weight of 5000. Polyester A was obtained.

  200 parts of urea-modified polyester I and 800 parts of unmodified polyester A were dissolved and mixed in 2000 parts of an ethyl acetate / MEK (1/1) mixed solvent to obtain an ethyl acetate / MEK solution of toner binder I. Part of the mixture was dried under reduced pressure to isolate toner binder I. As a result of analysis, Tg was 62 ° C.

-Preparation of toner 240 parts of ethyl acetate / MEK solution of toner binder I Ester wax (endothermic peak = 72 ° C., half-value width = 4 ° C.) 11.2 parts C.I. I. Pigment Blue 15: 3 4 parts The above raw materials were stirred in a beaker at 12000 rpm with a TK homomixer at 60 ° C., and uniformly dissolved and dispersed to prepare a toner material solution.

706 parts of ion-exchanged water 10% suspension of hydroxyapatite (Superpatite 10 manufactured by Nippon Chemical Industry Co., Ltd.)
294 parts Sodium dodecylbenzenesulfonate 0.2 part The above raw materials were placed in a beaker and dissolved uniformly. Thereafter, the temperature was raised to 60 ° C., and the toner material solution was added and stirred for 10 minutes while stirring at 12000 rpm with a TK homomixer. The mixture was then transferred to a stir bar and a flask equipped with a thermometer, heated to 30 ° C., the solvent was removed under reduced pressure, filtered, washed, dried, air-classified, and a weight average particle size of 6 Toner particles (13) of 5 μm were obtained.

  To 100 parts of the toner particles (13), 1.9 parts of hydrophobic silica fine powder having an average primary particle diameter of 10 nm treated with silicone oil, and 0.3 part of hydrophobized titanium oxide having an average primary particle diameter of 30 nm Was put directly into the Henschel mixer without the premixing step. The angle of the baffle plate was adjusted to be perpendicular to the inner diameter tangent of the Henschel mixer, and dry mixing was performed for 7 minutes at a peripheral speed of 35 m / s to obtain toner (13).

  The average circularity of the toner (13) was 0.975.

  Table 1 shows the physical property values of the toner.

[Toner Production Example 14]
Polyester resin (peak molecular weight 15,000, Tg = 80 ° C.) 100 parts C.I. I. Pigment Blue 15: 3 6.5 parts Low molecular weight polypropylene (Biscol 660P: manufactured by Sanyo Chemical Co., Ltd.) Melting point 145 ° C. 5 parts Bontron E-88 (manufactured by Orient Chemical Co., Ltd.) 1.8 parts Melting the above components with a Banbury mixer After kneading and cooling, the mixture was finely pulverized by a jet mill, and further spheronized using a surface modification device utilizing mechanical impact force to obtain a spherical pulverized raw material. Next, the obtained pulverized raw material was classified by a classifier to obtain toner particles (14) having a weight average particle diameter of 5.5 μm. To 100 parts of the toner particles (14), 1.7 parts of a hydrophobic silica fine powder having an average primary particle diameter of 12 nm, which has been treated with hexamethyldisilazane and then with silicone oil, and a hydrophobic having an average primary particle diameter of 30 nm The titanium oxide 0.3 parts was directly charged into the Henschel mixer without performing the premixing step. The angle of the baffle plate was adjusted to be perpendicular to the inner diameter tangent of the Henschel mixer, and dry mixing was performed for 7 minutes at a peripheral speed of 35 m / s to obtain toner (14).

  The average circularity of the toner (14) was 0.955.

  Table 1 shows the physical property values of the toner.

[Toner Production Example 15]
Toner (15) was produced by the following emulsion aggregation method.

<< Preparation of Resin Particle Dispersion 1 >>
・ 90 parts of styrene ・ 20 parts of n-butyl acrylate ・ 3 parts of acrylic acid ・ 6 parts of dodecanethiol ・ 1 part of carbon tetrabromide The above mixture was dissolved and dissolved in a nonionic surfactant (manufactured by Sanyo Chemical Co., Ltd.) : Nonipol 400) 1.5 parts and anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd .: Neogen SC) 2.5 parts dissolved in 140 parts of ion-exchanged water were dispersed in a flask and emulsified. Then, while slowly mixing for 10 minutes, 10 parts of ion-exchanged water in which 1 part of ammonium persulfate was dissolved was added thereto, and after replacing with nitrogen, until the contents reached 70 ° C. while stirring the flask. The mixture was heated in an oil bath and emulsion polymerization was continued for 5 hours. Thus, a resin particle dispersion 1 was prepared by dispersing resin particles having an average particle size of 0.17 μm, a glass transition point of 57 ° C., and a weight average molecular weight (Mw) of 11,000.

<< Preparation of resin particle dispersion 2 >>
・ Styrene 75 parts ・ N-butyl acrylate 25 parts ・ Acrylic acid 2 parts Mix and dissolve 1.5 parts of nonionic surfactant (Sanyo Kasei Co., Ltd .: Nonipol 400) and anionic interface Disperse 3 parts of an activator (Daiichi Kogyo Seiyaku Co., Ltd .: Neogen SC) in 140 parts of ion-exchange water in a flask, emulsify, and slowly mix for 10 minutes with ammonium persulfate. 10 parts of ion-exchanged water in which 0.8 part was dissolved was added, and after nitrogen substitution, the contents in the flask were heated with an oil bath until the temperature reached 70 ° C. while stirring, and the emulsion polymerization was carried out for 5 hours. Continuously, a resin particle dispersion 2 was prepared by dispersing resin particles having an average particle size of 0.1 μm, a glass transition point of 61 ° C., and a weight average molecular weight (Mw) of 550,000.

<< Preparation of release agent particle dispersion >>
・ Ester wax (melting point 65 ° C., half width 5 ° C.) 50 parts ・ Anionic surfactant 5 parts (Daiichi Kogyo Seiyaku Co., Ltd .: Neogen SC)
・ Ion-exchanged water 200 parts or more was heated to 95 ° C. and dispersed using a homogenizer (IKA: ULTRA TALLAX T50), then dispersed with a pressure discharge homogenizer, and the average particle size was 0.5 μm. A release agent particle dispersion was prepared by dispersing a release agent.

<< Preparation of Colorant Particle Dispersion 1 >>
・ Carbon black 20 parts ・ Anionic surfactant 2 parts (Daiichi Kogyo Seiyaku Co., Ltd .: Neogen SC)
-Ion exchange water 78 parts or more were mixed and dispersed using a sand grinder mill. When the particle size distribution in the colorant particle dispersion 1 was measured using a particle size measuring device (LA-700, manufactured by Horiba, Ltd.), the average particle size of the contained colorant particles was 0.2 μm and 1 μm. No coarse particles exceeding were observed.

<Preparation of charge control particle dispersion>
20 parts of a metal compound of di-alkyl-salicylic acid (charge control agent, Bontron E-88, manufactured by Orient Chemical Industries)
・ Anionic surfactant 2 parts (Daiichi Kogyo Seiyaku Co., Ltd .: Neogen SC)
-Ion exchange water 78 parts or more were mixed and dispersed using a sand grinder mill. When the particle size distribution in this charge control particle dispersion was measured using a particle size measuring device (LA-700, manufactured by Horiba, Ltd.), the average particle size of the charge control particles contained was 0.2 μm, and 1 μm No larger coarse particles were observed.

<Preparation of liquid mixture>
-Resin particle dispersion 1 250 parts-Resin particle dispersion 2 110 parts-Colorant particle dispersion 1 50 parts-Release agent particle dispersion 70 parts 1 liter equipped with a stirrer, cooling tube and thermometer Was put into a separable flask and stirred. The mixture was adjusted to pH = 5.2 using 1N potassium hydroxide.

<Agglomerated particle formation>
As a flocculant, 150 parts of a 10% sodium chloride aqueous solution was added dropwise to this mixed solution, and the flask was heated to 57 ° C. while stirring the inside of the flask. At this temperature, 3 parts of resin particle dispersion 2 and 10 parts of charge control agent particle dispersion were added. After maintaining at 50 ° C. for 1 hour, it was confirmed by observation with an optical microscope that aggregated particles (A) having an average particle diameter of about 5.3 μm were formed.

<Fusion process>
Then, after adding 3 parts of an anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd .: Neogen SC) here, the stainless steel flask was sealed and heated to 105 ° C. while stirring with a magnetic seal. And held for 1 hour. Then, after cooling, the reaction product was filtered, thoroughly washed with ion exchange water, and then dried to obtain toner particles (15).

  The obtained toner particles (15) had a weight average particle diameter of 5.5 μm and an average circularity of 0.950.

  To 100 parts of the toner particles (15), 3.0 parts of a hydrophobic silica fine powder having an average primary particle diameter of 7 nm, treated with hexamethyldisilazane and then with silicone oil, and silica having an average primary particle diameter of 800 nm 0.1 parts of the particles were charged directly into a Henschel mixer without performing the premixing step. The angle of the baffle plate was adjusted so as to be perpendicular to the inner diameter tangent of the Henschel mixer, and dry-mixed for 7 minutes at a peripheral speed of 35 m / s to obtain toner (15).

  Table 1 shows the physical property values of the toner.

[Toner Production Example 16]
Styrene-butyl acrylate copolymer (80/20) 100 parts octahedral magnetite 100 parts [average primary particle size is 0.25 μm, 10K Oersted saturation magnetization is 81.0 (Am ² / Kg), residual magnetization is 7 parts .0 (Am ² / Kg)]
Low molecular weight polypropylene (Biscol 660P: manufactured by Sanyo Chemical Co., Ltd.) Melting point 145 ° C. 4 parts Bontron E-88 (produced by Orient Chemical Co., Ltd.) 1.8 parts Fine pulverization was performed, and a spheronization treatment was performed using a surface modifying apparatus utilizing mechanical impact force to obtain a spherical pulverized raw material. Next, the obtained pulverized raw material was classified by a classifier to obtain toner particles having a weight average particle diameter of 6.5 μm.

  To 100 parts of the toner particles, 1.7 parts of hydrophobic silica fine powder having an average primary particle diameter of 12 nm, which has been treated with hexamethyldisilazane and then with silicone oil, and a hydrophobizing treatment with an average primary particle diameter of 30 nm 0.3 parts of titanium oxide was directly charged into a Henschel mixer without performing the premixing step. The angle of the baffle plate was adjusted to be perpendicular to the inner diameter tangent of the Henschel mixer, and dry mixing was performed for 7 minutes at a peripheral speed of 35 m / s to obtain toner (16).

  The average circularity of the toner (16) was 0.955.

  Table 1 shows the physical property values of the toner.

<Example 1>
The toner (1) was a non-magnetic one-component developer (1), and the following durability evaluation was performed using the image forming apparatus shown in FIG. 6 and the developing apparatus shown in FIG. . The image forming apparatus will be described below.

FIG. 6 is a schematic view of a modified 1200 dpi laser beam printer (manufactured by Canon: LBP-840) using a nonmagnetic one-component contact development type electrophotographic process. In this embodiment, a toner hopper unit that replenishes toner sequentially is added to the developing device, and a device that is further modified under the following conditions (a) to (i) is used.
(A) The charging method of the apparatus was direct charging performed by contacting a rubber roller, and the applied voltage was a direct current component (-1200 V).
(B) The toner carrier was changed to a medium resistance rubber roller (diameter 16 mm, hardness ASKER-C 45 degrees, resistance 10 ⁵ Ω · cm) made of silicone rubber dispersed with carbon black, and contacted with the photoreceptor.
(C) The toner carrying member was driven so that the rotational peripheral speed of the toner carrying member was in the same direction at the contact portion with the photosensitive member, and was 150% of the photosensitive member rotational peripheral speed.
(D) The process speed of the image forming apparatus in the present invention is 150 mm / sec, while the peripheral speed of the developing roller is 225 mm / sec.
(E) The photoconductor was changed to the following.

The photoreceptor used here was an Al cylinder as a substrate, and layers having the following constitution were sequentially laminated by dip coating to produce a photoreceptor.
Conductive coating layer: Mainly composed of a powder of tin oxide and titanium oxide dispersed in a phenol resin. Film thickness 15 μm.
-Undercoat layer: Mainly composed of modified nylon and copolymer nylon. Film thickness 0.6 μm.
Charge generation layer: Mainly composed of a titanyl phthalocyanine pigment having absorption in a long wavelength region dispersed in a butyral resin. Film thickness 0.6 μm.
Charge transport layer: Mainly composed of a hole-transporting triphenylamine compound dissolved in a polycarbonate resin (molecular weight 20,000 by Ostwald viscosity method) at a mass ratio of 8:10. Film thickness 20 μm.
(F) As a means for applying the toner to the toner carrier, an application roller made of urethane foam rubber was provided in the developing device and brought into contact with the toner carrier. A voltage of about −550 V is applied to the application roller.
(G) A resin-coated stainless steel blade was used to control the coat layer of the toner on the toner carrier.
(H) Only the DC component (-450 V) was applied during development.

  A commercially available paint is applied very thinly on the surface of a rubber roller having the same diameter, the same hardness, and the same resistance as the toner carrier used in the image forming apparatus, and after temporarily assembling the image forming apparatus, the rubber roller is removed, and an optical microscope The surface of the stainless steel blade was observed and the NE length was measured. The NE length was 1.05 mm.

  The electrophotographic apparatus was remodeled and process conditions were set as follows in order to conform to the remodeling of these process cartridges.

  The modified device uses a roller charger (applying only direct current) to uniformly charge the image carrier. Subsequent to charging, an image portion is exposed with a laser beam to form an electrostatic latent image, and a visible image is formed with toner, and then the toner image is transferred to a transfer material by a roller to which a voltage of +700 V is applied.

  As for the photosensitive member charging potential, the dark portion potential was set to -600V, and the bright portion potential was set to -150V.

  Under the above conditions, A4 size under normal temperature and humidity environment (23 ° C, 50% RH), high temperature and high humidity environment (30 ° C, 80% RH) and low temperature and low humidity environment (15 ° C, 10% RH) Then, after repeating the output of two images with a printing ratio of 1% for 10 seconds, the operation of resting for 10 seconds was repeated until a total of 30000 sheets was printed. A sample image shown in FIG. When the toner in the replenishing device 8 runs out, new toner is charged into the replenishing device 8 at that time and the durability is continued.

(1) Evaluation of solid density uniformity A full-scale solid image is output using ordinary A4 size copier plain paper (75 g / m ² ), and the output image is divided into three parts vertically and horizontally (total of 9 parts). The central density of each block was measured, and the uniformity of the solid density was evaluated by obtaining the maximum density difference from the following formula.
(Maximum density difference) = (Maximum density)-(Minimum density)

The image density was measured by using “Macbeth reflection densitometer RD918” (manufactured by Macbeth Co., Ltd.) to measure the relative density with respect to an image of a white background portion having a document density of 0.00.
A: Very good Less than 0.05 B: Good 0.05 or more, less than 0.10 C: No practical problem 0.10 or more, less than 0.30 D: Practical problem 0.30 or more

(2) Fog evaluation during replenishment A full solid white image was output, and fog during replenishment was evaluated by the following method. The fog at the time of replenishment refers to the fog value at the most severe condition where the durable toner and the replenishment toner are mixed at a high density when the high coverage image is output after the low coverage image is output. It was defined as time fog and evaluated.

  For the measurement of fog, use “REFLECTMETER MODEL TC-6DS” (manufactured by Tokyo Denshoku Co., Ltd.) to measure the reflectance of the white portion of the standard paper and the printout image. Calculated. The filter was measured by attaching amber for cyan, blue for yellow, green filters for magenta and black.

The evaluation criteria were determined according to the following criteria using the worst value on the entire solid white image.
A: Very good Less than 1.0% B: Good 1.0% or more to less than 2.0% C: No practical problem 2.0% or more to less than 3.0% D: Practical problem 3.0 More than%

(3) Halftone image uniformity evaluation An original chart in which horizontal band images of 30H, 40H, 50H, and 60H are arranged in the transfer paper conveyance direction is output, and this image is visually observed. Observed, the dot reproducibility and the presence or absence of vertical stripes along the transport direction caused by contamination of the developing blade were evaluated based on the following criteria. Note that the 30H halftone image is a value in which 256 gradations are displayed in hexadecimal, and indicates the image density when 00H is solid white and FFH is solid black.
A: All halftone images are vivid and uniform, and dots are reproduced with high accuracy.
B: Although a slight dot disturbance is confirmed in some halftone images, the level is hardly noticed.
C: A level where dots are disordered on some halftone images but not noticeable on practical images.
D: Level at which the quality of a practical image is greatly impaired, such as poor dot reproducibility on all half-tone images, an image with a rough impression, and vertical streak-like image defects due to contamination of the developing blade.

  When the toner 1 was evaluated under the above conditions, the image quality was not deteriorated throughout the endurance life in all environments, and the result was good. The results are shown in Table 2.

<Examples 2 to 11>
When toners 2 to 11 were evaluated under the same conditions as in Example 1, generally good results were shown. The results are shown in Table 2.

<Comparative Example 1>
When the toner 12 was evaluated under the same conditions as in Example 1, the value of D2 / D1 was large. Therefore, if a high printing command was issued when the physical property difference between the old and new toners increased, the mixing of the old and new toners occurred. Defects and non-uniform charging occurred, and fogging during replenishment and longitudinal density differences were at a level that could not withstand practical use. The results are shown in Table 2.

<Comparative example 2>
When the toner 13 was evaluated under the same conditions as in Example 1, since the D2 / D1 value was large and the D2 value was also small, the toner deterioration was promoted as the durability progressed, and the level that could not withstand practical use in the latter half of the durability. showed that. The results are shown in Table 2.

<Comparative Example 3>
When the toner 14 was evaluated under the same conditions as in Example 1, the D2 was small and the toner conveyance speed was increased to accelerate the deterioration. Therefore, in the latter half of the endurance, the replenishment toner was not mixed with the durable toner in the development region. As a result, the solid density became uneven and fogging during replenishment worsened. Also, the halftone image was inferior in dot reproducibility. The results are shown in Table 2.

<Comparative Example 4>
When the toner 15 was evaluated under the same conditions as in Example 1, because D2 was small and D2 / D1 was also small, the mixing of old and new toners was poor, the transportability was too high, and the degree of deterioration of the toner was large, and the latter half of the durability Showed unusable image quality such as development streaks. The results are shown in Table 2.

<Comparative Example 5>
In Example 1, the toner 16 was evaluated using the same developing unit configuration except that the system was changed to the LBP-840 system (manufactured by Canon Inc.) of the magnetic one-component jumping development method. As a result, D2 was large and D2 / D1 was small. Therefore, the toner was tight and packing was likely to occur in the dead space, and the toner deterioration was promoted, and the image quality was not able to withstand practical durability. The results are shown in Table 2.

Cross-sectional view of the developing device in the circumferential direction along the conveying direction in the present invention Blocking block diagram newly installed in the developing chamber in the present invention The blowing force from the supply roller along the conveyance direction and the supply amount image from the inlet in the present invention Solid density graph along the transport direction when using the developing method of the present invention in a hot and humid environment Other development chamber filling block diagram in the present invention Schematic sectional view of an image forming apparatus according to the present invention Schematic sectional view of an in-line full color image forming apparatus according to the present invention Circumferential sectional view of a conventional longitudinal circulation developing device Longitudinal sectional view of a conventional vertical circulation developing device Image of the supply force from the inlet and the blowing force from the supply roller along the transport direction when using the conventional development method Solid density graph and image measurement point diagram along the transport direction when using a conventional development method in a hot and humid environment The figure which shows the parts feeder (made by Konica Minolta) used for the transferability index measurement of the developer in this invention The figure which shows the charge amount measuring apparatus used for the charge amount measurement of the developer in this invention Schematic explanatory diagram of a Henschel mixer showing one specific example of a dry-type mixer used in producing the toner of the present invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Developing roller 2 Developer supply roller 3 Developer control member 4 Screw 5 Stirring member 6 Replenishing port 7 Replenishing device stirring member 8 Replenishing device 9 Stirring chamber 10 Developing chamber 11 Developing device 12 Developing container 16 Developing chamber-stirring chamber wall 17 Toner Replenishment amount 18 Agitating chamber toner surface 19 Inlet 20 Outlet 21 Developing chamber wall 23 Supply roller rotation direction 29 Photosensitive drum 30 Cleaner unit 31 Charging roller 32 Exposure device 33 Transfer roller 34 Fixing device 35 Intermediate transfer belt A Inlet toner conveyance amount B Screw conveyance amount C Outlet toner conveyance amount D Toner movement amount due to leveling by stirring member E Upward flow due to blowing from supply roller F Supply flow of toner supplied from inlet 40 Drive source 41 Ball 42 Slope 43 Slope upper end 44 Center axis 45 of ball 45 Trays 46 Weighing means 50 Suction machine 51 Constant container 52 conductive screen 53 lid 54 vacuum gauge 55 air-flow control valve 56 suction port 57 condenser 58 electrometer

Claims (18)

A developer carrying member for carrying at least the developer and performing development; a developer regulating member that is in contact with the surface of the developer carrying member to regulate the developer; and supplying the developer to the developer carrying member A developer supply member, a developer transport member provided above the rotation center axis of the developer supply member and transporting the developer in the longitudinal direction of the developer support, and the developer support A developer in a developer chamber configured to contain a developer container for supplying the developer, the developer carrier, the developer regulating member, the developer supply member, the developer transport member, and the developer container. A developer that is used in a development method having an inlet and an outlet for the developer from the stirring chamber,
The developing method includes a developer having a cross-sectional area vertically surrounded by a supply member rotation central axis in a region surrounded by the developer container excluding a developer transport region in a cross section perpendicular to the longitudinal direction of the developing chamber. The relationship between the cross-sectional area S1 on the upstream side in the transport direction of the developer generated by the transport member and the cross-sectional area S2 on the downstream side in the transport direction satisfies S1 <S2.
The developer is characterized in that the relationship between the bulk density (D1) and the static bulk density (D2) satisfies D2 / D1 = 1.22 to 1.42, and D2 = 0.42 to 0.55. Developer.   The developer according to claim 1, wherein the developer has a transportability index of 0.5 to 10.0.   The developer is mixed with the carrier at a ratio of 3% by mass, and the charge amount when shaken for 120 seconds is (Q1). After the measurement of (Q1), the developer is further added, and the mixing ratio with the carrier is 4 mass. The Q2 / Q1 satisfies the relationship of 0.8 to 1.2 when the charge amount when shaken for 60 seconds after adjusting to% is defined as (Q2). Developer.   The developer according to any one of claims 1 to 3, wherein the developer has a weight average particle diameter of 5.0 µm to 12.0 µm and an average circularity of 0.940 to 0.995.   5. The developer according to claim 1, wherein the developer contains 3 to 20 parts by mass of a release agent with respect to 100 parts by mass of the binder resin constituting the developer. Developer. The developer contains 1.0 to 2.0 parts by mass of silica fine particles having an average primary particle size of 5 nm to 40 nm with respect to 100 parts by mass of toner particles constituting the developer, and a BET of 1.5 to 3. The developer according to claim 1, wherein the developer is 0 m ² / g.   The developer has toner particles, and the toner particles are produced by polymerizing a polymerizable monomer composition containing at least a polymerizable monomer, a wax, and a colorant in an aqueous medium. The developer according to claim 1, wherein the developer is any one of the following.   The developer according to any one of claims 1 to 7, wherein the developing method is used for a system that replenishes nonmagnetic one-component toner sequentially.   The developer according to any one of claims 1 to 8, wherein the cross-sectional area continuously increases from a cross-sectional area S1 on the upstream side in the transport direction to a cross-sectional area S2 on the downstream side in the transport direction. A developer carrying member for carrying at least the developer and performing development; a developer regulating member that is in contact with the surface of the developer carrying member to regulate the developer; and supplying the developer to the developer carrying member A developer supply member, a developer transport member provided above the rotation center axis of the developer supply member and transporting the developer in the longitudinal direction of the developer support, and the developer support A developer in a developer chamber configured to contain a developer container for supplying the developer, the developer carrier, the developer regulating member, the developer supply member, the developer transport member, and the developer container. In the developing method, the developing chamber has an inlet and an outlet for the developer from the stirring chamber.
The developing method includes a developer having a cross-sectional area vertically surrounded by a supply member rotation central axis in a region surrounded by the developer container excluding a developer transport region in a cross section perpendicular to the longitudinal direction of the developing chamber. The relationship between the cross-sectional area S1 on the upstream side in the transport direction of the developer generated by the transport member and the cross-sectional area S2 on the downstream side in the transport direction satisfies S1 <S2.
The relationship between the bulk density (D1) and the static bulk density (D2) of the developer satisfies D2 / D1 = 1.22 to 1.42, and D2 = 0.42 to 0.55. Developing method.   11. The developing method according to claim 10, wherein the developer has a transportability index of 0.5 to 10.   The developer is mixed with the carrier at a ratio of 3% by mass, and the amount of charge when shaken for 120 seconds is (Q1). After the measurement (Q1), the developer is further added, and the mixing ratio with the carrier is 4 The Q2 / Q1 satisfies the relationship of 0.8 to 1.2 when the charge amount when shaken for 60 seconds after adjusting to mass% is (Q2). Development method.   The developing method according to claim 10, wherein the developer has a weight average particle diameter of 5.0 μm to 12.0 μm and an average circularity of 0.940 to 0.995.   The developer according to any one of claims 10 to 13, wherein the developer contains 3 to 20 parts by weight of a release agent with respect to 100 parts by weight of the binder resin constituting the developer. Development method. The developer contains 1.0 to 2.0 parts by mass of silica fine particles having an average primary particle size of 5 nm to 40 nm with respect to 100 parts by mass of toner particles constituting the developer, and a BET of 1.5 to 3. The developing method according to claim 10, wherein the developing method is 0 m ² / g.   The developer has toner particles, and the toner particles are produced by polymerizing a polymerizable monomer composition containing at least a polymerizable monomer, a wax, and a colorant in an aqueous medium. The developing method according to claim 10, wherein the developing method is a particle.   The developing method according to any one of claims 10 to 16, wherein the developing method is used in a system for sequentially replenishing non-magnetic one-component toner.   18. The developing method according to claim 10, wherein the cross-sectional area continuously increases from a cross-sectional area S1 on the upstream side in the transport direction to a cross-sectional area S2 on the downstream side in the transport direction.

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