Processing box

Abstract

The invention relates to a process cartridge. The process cartridge includes a developing roller, a toner supply roller, a toner adjusting member, and toner, a moving direction of a surface of the developing roller being opposite to a moving direction of a surface of the toner supply roller at a position where the surface of the developing roller is in contact with a surface of the toner supply roller, the developing roller and the toner supply roller are formed such that a circumferential speed ratio R satisfies a range of 1.1-2.5, and toner satisfying a predetermined requirement is used.

Description

Technical Field

[0001] The present disclosure relates to a process cartridge for a copying machine and a printer using an electrophotographic method or an electrostatic recording method. Background Art

[0002] In an image forming apparatus such as a printer using an electrophotographic image forming method (electrophotographic process), an electrophotographic photoreceptor (hereinafter, referred to as a "photoreceptor") used as an image bearing member is uniformly charged, and the charged photoreceptor is selectively exposed to form an electrostatic image on the photoreceptor. The electrostatic image formed on the photoreceptor is visualized as a toner image using a toner used as a developer. In addition, image recording is performed by transferring the toner image formed on the photoreceptor to a recording material such as recording paper or a plastic sheet and applying heat or pressure to the toner image transferred to the recording material so that the toner image is fixed on the recording material.

[0003] Such image forming apparatuses generally require the replenishment of developer and the maintenance of various processing units. In order to facilitate the replenishment operation of developer and the maintenance of various processing units of the image forming apparatus, a system of forming a processing cartridge detachably mounted to the main body of the image forming apparatus by combining a photoreceptor, a charging unit, a developing unit, a cleaning unit, etc. in a frame to form a cartridge has been put into practical use. According to the processing cartridge system, an image forming apparatus having excellent usability can be provided.

[0004] In recent years, color image forming apparatuses that form color images using developers of multiple colors have been widely used. As color image forming apparatuses, so-called tandem image forming apparatuses are known in which photosensitive bodies corresponding to respective image forming operations using developers of multiple colors are arranged in a row along the surface moving direction of a transfer material to which a toner image is transferred. Examples of tandem color image forming apparatuses include tandem color image forming apparatuses in which multiple photosensitive bodies are arranged in a row in a direction (e.g., horizontal direction) intersecting a vertical direction (gravity direction). Tandem image forming apparatuses are suitable image forming apparatuses in terms of high-speed image formation and the ability to easily cope with requirements such as the development of multi-function printers.

[0005] Examples of image forming apparatuses include image forming apparatuses in which a photoreceptor is arranged below an intermediate transfer member serving as a transfer material or a recording bearing member that conveys a recording material serving as a transfer material (see Japanese Patent Laid-Open No. 2011-253203). In the case where the photoreceptor is arranged below the intermediate transfer member or the recording material bearing member, for example, a fixing device and a developing device (or an exposure device) can be arranged at separate positions in a state where the intermediate transfer member and the recording material bearing member are sandwiched in the main body of the image forming apparatus. Therefore, the developing device (or the exposure device) and the fixing device can be arranged at separate positions, which is advantageous in that the developing device (or the exposure device) is less likely to be affected by the heat of the fixing device.

[0006] In recent years, there has been an increasing demand for improving productivity, and a printer capable of high-speed printing has been required. As a cartridge configuration capable of high-speed printing, a cartridge configuration is proposed in which a toner is satisfactorily supplied by configuring a developing roller serving as a recording material bearing member and a toner supplying roller for supplying the developer to the developing roller and causing a peripheral speed difference between the developing roller and the toner supplying roller (see Japanese Patent Laid-Open No. 2015-41047 and Japanese Patent Laid-Open No. 2020-79902).

[0007] In the case where it is desired to use these proposed configurations to achieve printing at higher speeds, there are the following problems: stability of colorant supply and charging stability in a high temperature and high humidity environment, in-plane concentration difference as the difference between the concentration at the upper end and the concentration at the lower end of the transfer material when developing a high-speed printed image, reduction in concentration, and fogging when performing white printing (solid white image). Summary of the invention

[0008] The present disclosure provides a process cartridge that stabilizes the amount of toner supplied to a developing roller to suppress the occurrence of in-plane concentration differences, and stabilizes the toner coating on the developing roller, thereby maintaining satisfactory image quality without deterioration of image quality, such as a decrease in image density or fogging.

[0009] According to the present disclosure, there is provided a process cartridge which can be mounted on an image forming apparatus, the process cartridge comprising:

[0010] Development room,

[0011] The developing room includes

[0012] a developing roller that develops the electrostatic latent image formed on the surface of the photosensitive drum using a toner to form a toner image,

[0013] a toner supplying roller that supplies toner to a developing roller,

[0014] a toner regulating member that regulates a layer thickness of toner on a developing roller, and

[0015] Toner,

[0016] The surface of the developing roller contacts the surface of the toner supply roller, and the moving direction of the surface of the developing roller is opposite to the moving direction of the surface of the toner supply roller at a position where the surface of the developing roller contacts the surface of the toner supply roller.

[0017] In a mounted state in which the process cartridge is mounted on the apparatus main body of the image forming apparatus, at a position where the surface of the developing roller contacts the surface of the toner supplying roller, the moving direction of the surface of the toner supplying roller includes an upward component,

[0018] The developing roller and the toner supplying roller are formed so that the peripheral speed ratio R represented by the formula (E1) satisfies 1.1≤R≤2.5,

[0019] R=V RS / V D (E1)

[0020] (In formula (E1), V RS represents the absolute value of the peripheral speed of the toner supply roller surface [m / sec], and V D represents the absolute value of the peripheral speed of the developing roller surface [m / s]),

[0021] The toner contains toner particles and silica fine particles,

[0022] The toner particles contain a crystalline resin component,

[0023] The content of the silica fine particles is 1.5 parts by mass or more and 5.0 parts by mass or less relative to 100 parts by mass of the toner particles,

[0024] The aggregation degree of the toner is 70.0% or more and 99.0% or less, and

[0025] When a cross section of a toner particle is observed using a transmission electron microscope, when the average area ratio of domains of a crystalline resin component in a surface layer region from the surface of the toner particle to a depth of 200 nm is defined as As, As is 1.0 area % or less.

[0026] Further features of the present invention will become apparent from the following description of exemplary embodiments with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 Schematic cross-sectional view showing an image forming apparatus to which the present disclosure can be applied.

[0028] Figure 2 Schematic cross-sectional view showing a process cartridge according to an embodiment to which the present disclosure can be applied.

[0029] Figure 3 Schematic cross-sectional view showing a developing chamber according to an embodiment to which the present disclosure can be applied.

[0030] Figure 4 1 is a conceptual cross-sectional view illustrating a lateral direction of a developing blade according to an embodiment to which the present disclosure can be applied.

[0031] Figure 5 1 is a diagram illustrating a driving / input method for a toner supplying roller according to an embodiment to which the present disclosure can be applied.

[0032] Figure 6 2 is a diagram illustrating movement of toner within a developing device according to an embodiment to which the present disclosure can be applied.

[0033] Figure 7 A diagram for describing a positional relationship between an inner wall of a developing chamber and a developing blade supporting end according to an embodiment to which the present disclosure can be applied. DETAILED DESCRIPTION

[0034] Hereinafter, the processing box according to the present disclosure will be described in more detail with reference to the accompanying drawings. Here, unless otherwise specified, the size, material, shape, relative configuration, etc. of the constituent components described in this embodiment are not intended to limit the scope of the present disclosure thereto. In addition, the material and shape, etc. of the components described once in the following description are the same as those in the subsequent description. Well-known or well-known techniques in the technical field can be applied to the composition or steps not described or shown in the figure. In addition, repeated descriptions may not be provided.

[0035] Unless otherwise specified, the description of “XX or more and YY or less” and “XX to YY” showing a numerical range means that the numerical range includes the lower limit and the upper limit as endpoints.

[0036] When a numerical range is described in segments, the upper and lower limits of each numerical range may be optionally combined.

[0037] In order to cope with the above problems, a method of improving the stability of toner supply and charging stability in a cartridge configuration in which the moving direction of the surface of the developing roller is opposite to the moving direction of the surface of the toner supply roller has been studied.

[0038] As a result, it was found that the above problems can be solved by appropriately controlling the aggregation degree of the toner, the presence state of the crystalline resin component, and the amount of silica fine particles used as an external additive within a certain range of R represented by formula (E1).

[0039] That is, the process cartridge of the present disclosure is a process cartridge that can be mounted on an image forming apparatus, and includes

[0040] Development room,

[0041] The developing room includes

[0042] a developing roller that develops the electrostatic latent image formed on the surface of the photosensitive drum using a toner to form a toner image,

[0043] a toner supplying roller that supplies toner to a developing roller,

[0044] a toner regulating member that regulates a layer thickness of toner on a developing roller, and

[0045] Toner,

[0046] The surface of the developing roller contacts the surface of the toner supply roller, and the moving direction of the surface of the developing roller is opposite to the moving direction of the surface of the toner supply roller at a position where the surface of the developing roller contacts the surface of the toner supply roller.

[0047] In a mounted state in which the process cartridge is mounted on the apparatus main body of the image forming apparatus, at a position where the surface of the developing roller contacts the surface of the toner supplying roller, the moving direction of the surface of the toner supplying roller includes an upward component,

[0048] The developing roller and the toner supplying roller are formed so that the peripheral speed ratio R represented by the formula (E1) satisfies 1.1≤R≤2.5,

[0049] R=V RS / V D (E1)

[0050] (In formula (E1), V RS represents the absolute value of the peripheral speed of the toner supply roller surface [m / sec], and V D represents the absolute value of the peripheral speed of the developing roller surface [m / s]),

[0051] The toner contains toner particles and silica fine particles,

[0052] The toner particles contain a crystalline resin component,

[0053] The content of the silica fine particles is 1.5 parts by mass or more and 5.0 parts by mass or less relative to 100 parts by mass of the toner particles,

[0054] The aggregation degree of the toner is 70.0% or more and 99.0% or less, and

[0055] When a cross section of a toner particle is observed using a transmission electron microscope, when the average area ratio of the domains of the crystalline resin component in a surface layer region from the surface of the toner particle to a depth of 200 nm is defined as As, As is 1.0 area % or less.

[0056] Hereinafter, the process cartridge of the present disclosure will be described in detail.

[0057] Image forming equipment

[0058] Figure 1 FIG. 1 is a diagram showing a schematic configuration of an image forming apparatus 100 including a process cartridge according to the present disclosure in a stationary state on a horizontal plane as in actual use. The image forming apparatus 100 is a full-color inline laser printer using an intermediate transfer method. Figure 1 As shown in the figure, four processing boxes 70 (70Y, 70M, 70C and 70K) that are detachably mounted to the image forming device are mounted on the image forming device by means of a mounting member (not shown). In addition, the upstream side of the processing box 70 along the mounting direction of the image forming device 100 is defined as the front side, and the downstream side thereof along the mounting direction is defined as the rear side.

[0059] An electrophotographic photosensitive drum (hereinafter referred to as a photosensitive drum) 1 (1a, 1b, 1c, and 1d) is arranged in each process box 70. In addition, process units such as a charging roller 2 (2a, 2b, 2c, and 2d), a developing roller 25 (25a, 25b, 25c, and 25d), and a cleaning member 6 (6a, 6b, 6c, and 6d) are integrally arranged around the photosensitive drum 1 of each process box 70. The charging roller 2 uniformly charges the surface of the photosensitive drum 1. The developing roller 25 develops the latent image formed on the photosensitive drum 1 with a developer (hereinafter referred to as a toner) for visualization. In addition, the cleaning member 6 transfers the toner image formed on the photosensitive drum 1 to a recording medium and removes the toner remaining on the photosensitive drum 1. In addition, the following will refer to Figure 2 and Figure 3 Details of the configuration and positional relationship of the photosensitive drum 1, the charging roller 2, the developing roller 25, and the cleaning member 6 will be described.

[0060] Furthermore, a scanner unit 3 that selectively exposes the photosensitive drum 1 based on image information to form a latent image on the photosensitive drum 1 is provided below the process cartridge 70 in the direction of gravity.

[0061] A cassette 17 containing a recording medium S is mounted at the lower portion of the apparatus main body 100 a .

[0062] In addition, a recording medium conveying unit is provided so that the recording medium S passes through the secondary transfer roller 69 and the fixing unit 74 and is conveyed above the apparatus main body 100a. In addition, an intermediate transfer unit 5 is provided above each process cartridge 70 (70Y, 70M, 70C, and 70K) as an intermediate transfer unit for transferring the toner image formed on each photosensitive drum 1 (1a, 1b, 1c, and 1d). The intermediate transfer unit 5 includes a driving roller 56, a driven roller 57, primary transfer rollers 58 (58a, 58b, 58c, and 58d) at positions facing the photosensitive drums 1 of each color, and a counter roller 59 facing the secondary transfer roller 69, and the transfer belt 50 is stretched on these rollers. In addition, the transfer belt 50 faces all the photosensitive drums 1, circulates and moves to contact the photosensitive drums 1, and a voltage is applied to the primary transfer rollers 58 (58a, 58b, 58c, and 58d) to perform primary transfer from the photosensitive drums 1 to the transfer belt 50. In addition, the toner of the transfer belt 50 is transferred to the recording medium S by applying a voltage to the counter roller 59 and the secondary transfer roller 69 arranged in the transfer belt 50.

[0063] In image formation, each photosensitive drum 1 is rotated, and the photosensitive drum uniformly charged by the charging roller 2 is selectively exposed to light from the scanner unit 3. In this way, an electrostatic latent image is formed on the photosensitive drum 1. The latent image is developed by the developing roller 25. In this way, a toner image of each color is formed on each photosensitive drum 1. In synchronization with the image formation, the registration roller pair 55 conveys the recording medium S to the secondary transfer position where the counter roller 59 and the secondary transfer roller 69 contact each other with the transfer belt 50 sandwiched therebetween. In addition, the toner images of each color on the transfer belt 50 are secondarily transferred to the recording medium S by applying a transfer bias to the secondary transfer roller 69. In this way, a color image is formed on the recording medium S. The recording medium S on which the color image is formed is heated and pressurized by the fixing unit 74 so that the toner image is fixed. Thereafter, the recording medium S is discharged to the discharge unit 75 by the discharge roller 72. Furthermore, a fixing unit 74 is arranged on the upper portion of the apparatus main body 100 a .

[0064] Processing box

[0065] Next, we will refer to Figure 2 The process cartridge 70 to which the present disclosure is applied will be described. Figure 2 Shown in the installation Figure 1 The main section of the process cartridge 70 containing toner is shown in the state on the image forming apparatus 100. In addition, the cartridge 70Y containing yellow toner, the cartridge 70M containing magenta toner, the cartridge 70C containing cyan toner, and the cartridge 70K containing black toner have the same configuration.

[0066] The process cartridge 70 includes a cleaning unit 26 and a developing unit 4. The cleaning unit 26 includes a photosensitive drum 1, a charging roller 2, and a cleaning member 6. Furthermore, the developing unit 4 includes a developing roller 25.

[0067] As described above, the charging roller 2 and the cleaning member 6 are arranged on the circumference of the photosensitive drum 1. The cleaning member 6 includes an elastic member 7 formed of a rubber scraper and a cleaning support member 8. The front end portion of the elastic member 7 formed of a rubber scraper is arranged to contact the photosensitive drum in the opposite direction relative to the rotation direction of the photosensitive drum 1. In addition, the residual toner removed from the surface of the photosensitive drum 1 by the cleaning member 6 falls into the removed toner chamber 27.

[0068] The photosensitive drum 1 is rotationally driven in response to the image forming operation by transmitting the driving force of a main body driving motor (not shown) serving as a driving source to the cleaning unit 26. Here, when a drum coupling fixed to a longitudinal end of the photosensitive drum 1 is engaged with a main body side coupling existing on the longitudinal axis of the photosensitive drum 1, the driving force is input to the photosensitive drum 1. The charging roller 2 is rotatably attached to the cleaning unit 26 via a charging roller bearing, is pressed toward the photosensitive drum 1 by a charging roller pressing member, and is rotated driven by the photosensitive drum 1.

[0069] The developing unit 4 is formed of a developing roller 25 rotating in contact with the photosensitive drum 1 and a developing frame 31 supporting the developing roller 25. The developing frame 31 is formed of a developing chamber 31b and a toner containing chamber 31a (toner containing unit), and the toner containing unit is arranged vertically below the developing chamber.

[0070] A toner supply roller 34 that rotates in the direction indicated by the arrow C in contact with the developing roller 25 and a regulating member (developing blade 35) for regulating the toner layer on the developing roller 25 are arranged on the circumference of the developing roller 25. In the embodiment described below, the outer diameter of the developing roller 25 is 12 mm, and the outer diameter of the toner supply roller 34 is 13.2 mm. In a state where the process cartridge 70 is mounted on the image forming apparatus 100, an angle α between a horizontal line H and a straight line A connecting a rotation center 25e of the developing roller 25 and a rotation center 34e of the toner supply roller 34 is 9.85 degrees. However, the angle α is not limited thereto, and is, for example, in the range of 9.5° to 10.3°.

[0071] The developing roller 25 and the toner supplying roller 34 are rotationally driven in response to the image forming operation by transmitting the driving force of a main body driving motor (not shown) which is different from the driving source of the cleaning unit to the developing unit 4. The driving force is input by a driving input method via a coupling similarly to the case of the cleaning unit 26. The driving input method using a coupling is suitable from the viewpoint of rotation stability compared to the driving input method via gears.

[0072] The developing roller 25 is an elastomer roller formed so that a conductive elastic rubber layer having a predetermined volume resistivity is provided as an elastic layer around a metal core shaft. The developing roller 25 is formed by a base layer and a surface layer. The base layer is formed by silicone rubber, the surface layer is formed by polyurethane rubber, and polyurethane bead particles are dispersed in the polyurethane rubber of the surface layer to set the desired roughness. The developing roller 25 and the photosensitive drum 1 each rotate so that their surfaces move in the same direction (from the bottom to the top in this embodiment) at the opposing portion (contact portion). In the following embodiment, the toner negatively charged by frictional charging is transferred only to the bright area potential portion due to its potential difference in the developing unit in contact with the photosensitive drum 1, so that the electrostatic latent image is visualized.

[0073] The developing scraper 35 (regulating member) is arranged below the developing roller 25, contacts the developing roller 25 in the reverse direction, and regulates the coating amount and applied charge of the toner supplied by the toner supply roller 34. In the present embodiment, the developing scraper 35 is formed by a flexible plate-like member and a developing scraper 35 support body that fixes the plate-like member. The plate-like member is a member having a thickness of 80 μm obtained by processing stainless steel (SUS) into a leaf spring shape, and the contact portion at the free end of the plate-like member contacts the developing roller 25 with a desired contact pressure.

[0074] The toner supplied to the developing roller 25 is triboelectrically charged due to the friction between the developing scraper 35 and the developing roller 25, and its layer thickness is adjusted while the charge is applied. In addition, in the present embodiment, a predetermined voltage is applied from a scraper bias power supply (not shown) to the developing scraper 35 so that the toner coating is stabilized.

[0075] The toner to which the charge is applied adheres to the surface of the developing roller 25 due to the image force with the developing roller 25. In the case where the adhesion force of the toner to the surface of the developing roller 25 exceeds the regulating force of the developing blade 35, the toner coating on the developing roller 25 is disturbed (so-called "malregulation"). When the malregulation occurs, image defects such as fogging and density abnormality in which the toner adheres to the white background of the image occur.

[0076] Here, the developing blade 35 of this example will be described in detail. Figure 7 As shown in FIG. 1 , the developing blade 35 is formed of a support plate 35a (blade support portion) obtained by processing stainless steel and a plate-like member 35b (blade portion) having flexibility. The plate-like member and the support plate are integrated by YAG laser welding. Figure 4 2 is a conceptual diagram of the free end leading end portion of the development blade 35 according to the present disclosure in the lateral direction. Figure 4 The surface 811 is the surface that mainly contacts the developing roller 25 .

[0077] Figure 3 1 is an enlarged schematic cross-sectional view showing the interior of the developing chamber 31b, and showing a configuration in which the problem of the present disclosure occurs. Although the details will be described below, the toner supply roller 34 supplies the toner to the developing roller 25 by rotating in the C direction, but since an upward component is provided at the contact portion between the developing roller 25 and the toner supply roller 34, the problem may be caused by a configuration that is unfavorable for supplying the toner to the developing roller (this is because the toner to be supplied is affected by gravity).

[0078] In this embodiment, if Figure 4 As shown in FIG. 1 , a portion of the “front end edge portion 818” on the side in contact with the developing roller 25 is scraped by grinding the front end (free end) side of the plate-like member 35b. The portion formed by scraping is formed over the entire length region of the plate-like member.

[0079] The developing blade 35 is provided at a free end of the plate-like member 35 b in the widthwise direction and includes a contact portion that comes into contact with the surface of the developing roller 25 .

[0080] More specifically, before the front end of the developing scraper 35 is ground, the first surface 811 (first portion) which is the surface on the side in contact with the developing roller 25 and the third surface 813 (third portion) which is orthogonal to the first surface 811 intersect on the cross section orthogonal to the longitudinal direction to form the above-mentioned "front end edge portion 818". In addition, the front end edge portion 818 is scraped by grinding, thereby forming the second surface 812 (second portion) connecting the first surface 811 and the third surface 813. In the state after the grinding, the front end point of the first surface 811 on the free end side is defined as point A, and the front end point of the second surface 812 on the free end side is defined as point B. In addition, a virtual line extending from the first surface 811 in the free end direction is defined as L1. In addition, the point where the virtual line L2 which is orthogonal to the virtual line L1 and passes through point B intersects with the virtual line L1 is defined as point C. Here, the distance between point B and point C is defined as h1, and the distance between point A and point C is defined as d1. In the following embodiments, "h1 = 15 μm" and "d1 = 40 μm" are satisfied.

[0081] Here, the method of grinding the developing scraper 35 used in the present disclosure will be described. The plate-like member before being joined to the supporting member is fixed to the base in a state of being clamped between the base and the pressing member. The grinding film wound around the rubber roller is in contact with the front end of the plate-like member in a state where a load is applied to the grinding film. In the following embodiment, a wrapping film sheet with a particle size of #800 is used as the grinding film, and a load of 500 g is applied to the rubber roller.

[0082] The abrasive film on the rubber roller is arranged in a fixed state, and the base is moved left and right in the length direction so that the front end portion of the plate-like member rubs against the abrasive film and is thereby finely scraped.

[0083] The scraping amount of the plate-like member is proportional to the distance of friction between the plate-like member and the grinding film, and the scraping amount increases as the friction distance increases and decreases as the distance decreases. That is, the scraping amount of the front end edge of the plate-like member can be changed by controlling the movement amount of the base. The grinding method is only an example, and the present disclosure is not limited thereto, as long as the front end shape of the developing scraper can be processed into a desired shape.

[0084] The toner supply roller 34 is in the roller nip portion N2 (hereinafter referred to as Figure 6 ) contacts the developing roller 25, and is driven to rotate in response to the image forming operation by receiving the driving force of a driving motor (not shown). Figure 5 Provide a description of it.

[0085] The driving force from the main driving motor is transmitted to the coupling 201 (driving force receiving unit) provided at the shaft end of the toner supply roller 34, and the driving force is transmitted to the toner supply roller 34 through the intermediate body 202 and the driving transmission member 203 (the intermediate body 202 and the driving transmission member 203 are the first driving force transmission unit). The driving force of the toner supply roller 34 is transmitted to the developing roller 25 through the gears (204a to 204c) provided between the toner supply roller 34 and the developing roller 25 so that the developing roller 25 rotates (the gear 204c is the second driving force transmission unit, and the gear 204a is the third driving force transmission unit). Specifically, the gear 204c fixed to the toner supply roller 34 rotates to transmit the driving force to the intermediate gear 204b, so that the intermediate gear 204b rotates. When the intermediate gear 204b rotates, the driving force is transmitted to the gear 204a fixed to the developing roller 25, so that the developing roller 25 rotates together with the gear 204a.

[0086] exist Figure 1 and Figure 2 In the present embodiment shown in FIG. 1 , the driving force from the apparatus main body 100a to the developing unit 4 is input from the longitudinal axis of the toner supply roller 34, but in the case of adopting a configuration in which the driving force from the apparatus main body 100a to the developing unit 4 is input from the longitudinal axis of the developing roller 25, the driving input positions for the cleaning unit 26 and the developing unit 4 are close to each other because development is performed in a state in which the photosensitive drum 1 and the developing roller 25 are in contact with each other. Such a configuration of the input unit makes it difficult to simply configure the driving input unit of the apparatus main body 100a, which is not suitable when configuring a more stable driving input unit at a low cost.

[0087] On the contrary, in this embodiment, since the driving force for the developing unit 4 is input from the longitudinal axis of the colorant supply roller 34, the distance between the driving input position for the cleaning unit 26 and the driving input position for the developing unit 4 can be increased, which is more suitable when constituting the driving input unit of the device main body 100a.

[0088] Meanwhile, since the configuration in which the driving force from the apparatus main body 100a is transmitted to the developing roller 25 via the toner supply roller 34 requires driving the developing roller 25 via a plurality of gears, the rotation stability of the developing roller 25 is deteriorated compared to the configuration in which the driving force is transmitted to the developing roller 25. As a result, the regulating force of the developing blade 35 is unstable in some cases, and thus this configuration is disadvantageous in terms of poor regulation.

[0089] Further, the toner supplying roller 34 and the developing roller 25 rotate in opposite directions at a peripheral speed difference at the nip portion N2 , and supplies toner to the developing roller 25 while recovering the residual toner on the developing roller 25 .

[0090] In the present disclosure, the peripheral speed of the toner supply roller 34 at the nip portion N2 is defined as V RS And the peripheral speed of the developing roller 25 is defined as V D In the case of , the roller rotates so that the peripheral speed ratio R represented by the formula (E1) satisfies "1.1≤R≤2.5".

[0091] R=V RS / V D (E1)

[0092] (In formula (E1), V RS represents the absolute value of the peripheral speed of the toner supply roller surface [m / sec], and V D Represents the absolute value of the peripheral speed of the developing roller surface [m / s]).

[0093] That is, when the radius of the colorant supply roller 34 is defined as rRS and its rotational angular velocity is defined as ωRS, and the radius of the developing roller 25 is defined as rD and its rotational angular velocity is defined as ωD, the rotational angular velocity ratio λ between the colorant supply roller 34 and the developing roller 25 expressed by the formula (E2) "λ=ωRS / ωD" satisfies "1.1≤λ×rRS / rD≤2.5".

[0094] Furthermore, in the embodiment described below, since the radius of the toner supply roller is 3.3 mm and the radius of the developing roller is 3.0 mm, “λ≈1.14” is satisfied.

[0095] When the peripheral speed ratio R is set to satisfy "1.1≤R≤2.5", the toner supply roller rotates faster than the developing roller when developing at a high speed, the toner supply speed to the developing roller is sufficiently high or the opposing speed between the developing roller and the toner supply roller is high, so the toner supplied in a clumped state on the developing roller can be broken up by the toner supply roller. The peripheral speed ratio R is, for example, "1.2≤R≤1.5".

[0096] In the case where the peripheral speed ratio R is less than 1.1, when the toner is supplied to the developing roller in an aggregated state, the relative speed between the developing roller and the toner supply roller is insufficient, so that the toner is not sufficiently broken. Therefore, the covering state on the developing roller is disturbed, and as a result, the charging uniformity is disturbed and fogging occurs. Meanwhile, in the case where the peripheral speed ratio R is greater than 2.5, the toner on the developing roller is sufficiently broken, but the toner supply on the developing roller is insufficient because the toner supply roller rotates at a speed exceeding the toner supply speed to the developing chamber. Therefore, the image density is likely to be reduced, and due to the insufficient stability of the toner supply, the in-plane density difference is likely to occur.

[0097] Furthermore, the amount of the residual toner recovered on the developing roller 25 and the amount of toner supplied to the developing roller 25 can be adjusted by adjusting the potential difference between the toner supply roller 34 and the developing roller 25 .

[0098] Further, the toner supplying roller 34 and the developing roller 25 are in contact with each other by a predetermined intrusion amount (ie, a recessed amount ΔE by which the toner supplying roller 34 is formed into a recessed shape by the developing roller 25 ).

[0099] The toner supply roller 34 includes a conductive support and a foam layer supported by the conductive support. Specifically, the toner supply roller 34 is provided with a conductive support having an outer diameter of The core electrode and the polyurethane foam layer which is a foam layer formed of a continuous bubble body (connected bubble) formed by bubbles connected around the core electrode are rotated in the direction indicated by C in the figure. When the polyurethane of the surface layer is formed into a continuous bubble body as described above, a large amount of toner can enter the interior of the toner supply roller 34. In addition, the resistance of the toner supply roller 34 in the following embodiment is 1×10 9 (Ω).

[0100] In addition, in the following embodiment, the intrusion amount of the toner supply roller 34 into the developing roller 25 (ie, the depression amount ΔE of the toner supply roller 34 formed into a depressed shape by the developing roller 25 ) is set to 1.0 mm.

[0101] Here, a method of measuring the resistance of the toner supply roller 34 will be described. The toner supply roller 34 is in contact with an aluminum sleeve having a diameter of 30 mm so that the intrusion amount described below reaches 1.5 mm. When the aluminum sleeve rotates, the toner supply roller 34 rotates at 30 rpm relative to the aluminum sleeve.

[0102] Next, a DC voltage of -50 V is applied to the developing roller 25. In this case, a resistor of 10 kΩ is set on the ground side, and the resistance of the toner supply roller 34 is calculated by measuring the voltage across the resistor and calculating the current. In the present embodiment, the surface cell diameter of the toner supply roller 34 is set within a range of 50 μm to 1000 μm.

[0103] Here, the cell diameter represents the average diameter of the foamed cells in the optional cross section, and the maximum cell diameter is obtained by measuring the area of ​​the largest foamed cell from the enlarged image of the optional cross section and converting the area into a perfect circle equivalent diameter. In addition, the average diameter is the average value of the cell diameters similarly converted from the cell areas of the remaining cells after removing the foamed cells having a cell diameter of 1 / 2 or less of the maximum cell diameter as noise.

[0104] The toner supplied from the toner supply roller 34 to the surface of the developing roller 25 is triboelectrically charged by the friction between the developing blade 35 and the developing roller 25, and the layer thickness is adjusted while applying the charge. Thereafter, the toner is conveyed to the contact portion (developing unit) between the photosensitive drum 1 and the developing roller 25, and is transferred to the light area potential portion. The residual toner remaining on the surface of the developing roller 25 is returned to the inside of the developing container again, is recovered from the surface of the developing roller 25 by the toner supply roller 34, and is contained inside the toner supply roller 34.

[0105] Here, we will refer to Figure 6 The toner flow inside the developing chamber 31b is described. Figure 6 is an enlarged schematic cross-sectional view showing the interior of the developing chamber 31b, and shows Figure 2 The movement of the toner conveying member 36 conveying to the toner supplying roller 34 is shown in FIG.

[0106] A portion of the toner G conveyed to the upper portion of the toner supply roller 34 by the toner conveying member 36 is sucked into the toner supply roller 34 due to the restoration of the toner supply roller 34 on the downstream side of the roller nip portion N2 in the rotation direction of the toner supply roller 34 (F1), and is contained inside the toner supply roller 34 together with the residual toner contained inside the toner supply roller 34 recovered from the surface of the developing roller 25. In addition, due to the rotation of the toner supply roller 34 in the direction indicated by C, the toner is conveyed to the downstream side of the roller nip portion N2 in the rotation direction of the toner supply roller 34. Due to the deformation of the toner supply roller 34 caused when the toner supply roller 34 contacts the developing roller 25 on the downstream side of the rotation direction of the toner supply roller 34, the toner contained inside the toner supply roller 34 is ejected (F2).

[0107] The toner ejected from the toner supply roller 34 that does not reach the surface of the developing roller 25 is gradually transported by the propulsion force in the direction of the developing opening (opening portion) due to the ejection force caused by the ejection from the toner supply roller 34, passes through the developing opening, and returns to the toner containing chamber 31a (F3).

[0108] When the toner circulates satisfactorily between the developing chamber 31b and the toner containing chamber 31a as described above, deterioration of the toner is suppressed, and occurrence of toner aggregation is suppressed even when images with a low print rate are continuously output, so high-quality images can be stably output.

[0109] Here, when the toner flow (F3) returned to the toner containing chamber 31a is insufficient, the toner is accumulated and gathered in the area below the toner supply roller 34 and the developing roller 25. In this way, the toner enters the roller gap portion N2 between the toner supply roller 34 and the developing roller 25, and the contact between the toner supply roller 34 and the developing roller 25 is insufficient. An area where the residual toner on the developing roller 25 cannot be sufficiently recovered by the toner supply roller 34 is generated, and a specific toner is carried by the developing roller 25 and passes through the contact portion between the developing blade 35 and the developing roller 25 unnecessarily, thereby generating an overcharged toner. As a result, the adhesion force of the toner exceeds the regulating force of the developing blade 35, and therefore, poor regulation occurs in some cases.

[0110] For example, in the case of continuously outputting images with a low print rate under a low temperature and low humidity environment, such a phenomenon is likely to occur. This is because the residual toner recovered from the developing roller 25 by means of the toner supply roller 34 accumulates in the developing chamber 31b. Since the residual toner recovered from the developing roller 25 is charged, the toner is likely to be electrostatically accumulated. In this way, the fluidity of the toner inside the developing chamber 31b is reduced, the toner flow (F3) returned to the toner containing chamber 31a is insufficient, and the toner is likely to be accumulated in the area below the toner supply roller 34 and the developing roller 25.

[0111] In order to deal with this problem, a method can be used in which a toner conveying member is arranged inside the developing chamber 31b below the toner supply roller 34 to generate a toner flow (F3) that returns to the toner containing chamber 31a. However, since toner degradation is promoted due to friction between the toner inside the developing chamber 31b and the toner conveying member when the toner conveying member is arranged inside the developing chamber 31b, toner melt adhesion to the developing roller 25 is observed in the case of continuous output of images with a low print rate. In addition, inside the developing chamber 31b, a toner conveying member needs to be arranged as an additional member in addition to the toner supply roller 34, so the structure of the device is complicated. Therefore, in the following embodiment, inside the developing chamber 31b, no member driven by a motor drive is arranged except for the developing roller 25 and the toner supply roller 34.

[0112] In the configuration in which no member other than the developing roller 25 and the toner supply roller 34 is disposed in the developing chamber 31b, the inner wall of the developing chamber 31b is set relative to the toner supply roller 34 as follows, thereby effectively using the toner in the developing chamber 31b. Figure 7 Provide instructions in detail.

[0113] Figure 7 R1 and R2 in the figure are tangent lines (vertical lines) of the outer peripheral surface of the toner supply roller 34 extending in the vertical direction. In addition, the horizontal line H2 is a horizontal line passing through the support end of the developing blade 35. At least a part of the area between R1 and R2 on the inner wall of the developing chamber 31b is above the horizontal line H2 in the vertical direction (area 138 in the figure). In this way, the amount of toner remaining in the developing chamber 31b and not used for printing can be further reduced, and the toner inside the developing chamber 31b can be used more effectively.

[0114] In addition, if Figure 2 As shown in FIG. 1 , the spray prevention sheet 20 is configured as a development contact sheet for preventing toner from leaking from the development frame 31 in contact with the development roller 25 .

[0115] Furthermore, the toner containing chamber 31a of the developing frame 31 is provided with a toner conveying member 36 for stirring the contained toner and conveying the toner to the toner supplying roller 34. Figure 2 As shown in FIG. 1 , the toner conveying member 36 is formed of a stirring shaft 36 a rotatable by a driving force from the apparatus body 100 a and a sheet member 36 b attached to and rotating together with the stirring shaft 36 a , and the sheet member 36 b has elasticity.

[0116] Next, the toner conveyance of the developing unit will be described. The sheet member 36b of the toner conveying member in the toner containing chamber 31a is arranged so that the free end of the toner conveying member contacts the wall surface of the toner containing unit in the region A on the upstream side of the opening portion 31c (communication port) in the rotation direction of the toner conveying member. In addition, as the toner conveying member rotates, the sheet member 36b is deformed against elasticity so that the free end side, rather than the rotation axis side, is on the upstream side in the rotation direction of the toner conveying member.

[0117] That is, the sheet member 36b contacts the deformation unit 31a1 on the inner surface of the toner containing unit as it rotates. In this way, the sheet member 36b receives the force from the deformation unit 31a1. As a result, the sheet member 36b is deformed against the elastic force of the sheet member 36b. In addition, the sheet member 36b rotates in a state of contact with the deformation unit 31a1, and the toner is conveyed in a state of being carried on the surface on the downstream side of its rotation direction. In this embodiment, the deformation unit 31a1 represents Figure 2 The inner wall of the toner containing chamber shown in FIG. 1 extends to a portion separated from the sheet member 36 b (also referred to as area A).

[0118] In addition, at a predetermined position (also referred to as position B) in the restoration unit 31a2, the free end of the toner conveying member is released from contact with the wall surface of the toner containing unit, and the restoration unit 31a2 is on the downstream side of the rotation direction of the toner conveying member in the region A and on the upstream side of the opening in the rotation direction of the toner conveying member. In this case, the deformed toner conveying member is elastically restored, and the conveyed toner flies toward the communication port. In this embodiment, the restoration unit 31a2 is arranged above the horizontal plane including the rotation axis of the stirring member.

[0119] Therefore, as the sheet member 36b rotates, after the front end of the sheet member 36b on the free end side passes through the deformation unit 31a1, the contact between the restoration unit 31a2 and the inner wall of the sheet member 36b is released. In this way, the sheet member 36b is released from the deformed state by the deformation unit 31a1 and restored to the natural state (original shape) by the elastic restoring force of the sheet member 36b. Due to the shape change of the sheet member 36b along the restoration direction, the toner transported by being carried on the sheet member 36b flies toward the opening 31c against gravity. The opening 31c is located on the downstream side of the restoration unit 31a2 along the rotation direction of the sheet member 36b. Some of the toner flying toward the opening 31c is transported to the developing chamber 31b. At the same time, the toner that does not reach the inside of the developing chamber 31b falls into the toner holding chamber 31a, remains at the bottom of the toner holding chamber 31a, and returns to the original state again. The toner is stirred and conveyed by repeating this cycle.

[0120] In addition, the boundary between the deformation unit 31a1 and the restoration unit 31a2 is below the lower end of the opening 31c (communication port), and when viewed along the axial direction of the developing roller 25, the rotation center of the colorant conveying member 36 and the rotation center of the developing roller 25 are located on the same side relative to the vertical line passing through the boundary, and the maximum value of the rotation radius of the colorant conveying member 36 is greater than the distance between the rotation center of the conveying member and the lower end of the communication port.

[0121] The configuration including the deformation unit 31a1 and the restoration unit 31a2 is advantageous for improving the efficiency of conveying the toner to the developing chamber 31b, but this configuration is likely to hinder the toner flow (F3) returning to the toner containing chamber, so that poor regulation tends to occur.

[0122] In the embodiment described below, the length of the rotation axis of the sheet member 36b in the natural state in the rotation radius direction is set to be greater than the distance from the rotation axis to the lower end of the developing opening in the same direction. This configuration is advantageous for improving the efficiency of conveying the toner to the developing chamber 31b, but is likely to hinder the toner flow (F3) returning to the toner containing chamber 31a, so that poor regulation tends to occur.

[0123] Furthermore, in the embodiment described below, two sets of sheet members 36b are attached to different attachment positions on the stirring shaft 36a, thereby enabling a sufficient amount of toner to be conveyed from the toner containing chamber 31a to the developing chamber 31b. This configuration is advantageous for improving the efficiency of conveying toner to the developing chamber 31b, but is likely to hinder the toner flow (F3) returning to the toner containing chamber 31a, so that misregulation tends to occur.

[0124] Toner

[0125] Next, the toner according to the present disclosure will be described in detail.

[0126] In the above-mentioned cartridge configuration, the above-mentioned problems can be solved by a toner exhibiting the following characteristics.

[0127] That is, the toner contains toner particles and silica fine particles,

[0128] The toner particles contain a crystalline resin component,

[0129] The content of the silica fine particles in the toner is 1.5 parts by mass or more and 5.0 parts by mass or less relative to 100 parts by mass of the toner particles,

[0130] The aggregation degree of the toner is 70.0% or more and 99.0% or less, and

[0131] When a cross section of a toner particle is observed using a transmission electron microscope, when the average area ratio of the domains of the crystalline resin component in a surface layer region from the surface of the toner particle to a depth of 200 nm is defined as As, As is 1.0 area % or less.

[0132] Here, the toner of the cartridge according to the present disclosure has a high aggregation degree of 70.0% or more and 99.0% or less. In the case where the aggregation degree of the toner is within the above range, in the cartridge configuration according to the present disclosure, the toner is carried on the surface of the toner supply roller in a state of forming an aggregate, so that the amount of toner to be supplied to the developing roller increases and exhibits high concentration stability. In the case where the aggregation degree is less than 70.0%, when the toner is supplied at a high speed, the aggregate of the toner carried by the toner supply roller collapses, and the toner conveying force is insufficient, thereby deteriorating the concentration stability. Meanwhile, in the case where the aggregation degree is higher than 99.0%, the aggregation force of the toner is extremely high, so that the toner on the developing roller is difficult to break using the toner supply roller. As a result, the coverage on the developing roller is disturbed, causing the toner to be unstably charged, and therefore, fogging is likely to occur. The aggregation degree of the toner is, for example, 75.0% or more and 97.5% or less, and, for example, 80.0% or more and 95.0% or less.

[0133] Furthermore, it is proposed that when toner particles come into contact with each other, a high aggregation force is exhibited by contact between the surfaces of the toner particles. Therefore, the degree of aggregation largely depends on the amount of silica fine particles that impart fluidity to the toner.

[0134] Furthermore, when observing the cross-section of the colorant particles using a transmission electron microscope, where the average area ratio of the domains of the crystalline resin component in the surface region from the surface of the colorant particles to a depth of 200 nm is defined as As, when As is 1.0 area % or less, the crushability of the toner aggregates at the roller gap portion between the developing roller and the toner supply roller is excellent, which improves the coverage uniformity of the colorant supplied to the developing roller, and thus fogging is less likely to occur.

[0135] The domain of the crystalline resin component is a part where the crystalline resin component is in a crystalline state. In addition, the uncrystallized crystalline resin component is compatible around the domain of the crystalline resin component. Therefore, the resin around the domain of the crystalline resin component has a more deteriorated mechanical strength and heat resistance compared to the resin at the part where the domain does not exist. In the present disclosure, it is presumed that the crushability of the toner particles in the aggregated state is improved due to the absence of the domain of the crystalline resin component around the toner surface.

[0136] Therefore, by controlling the toner particles to be in a state where the domain of the crystalline resin component present near the surface of the toner particles does not exist near the surface layer, excellent crushing properties are exhibited under pressure while maintaining high agglomeration. At the same time, when As is greater than 1.0 area%, a large amount of crystals of the crystalline resin component are present in the surface layer, thereby reducing the agglomeration force. Therefore, the crushing properties are deteriorated. In addition, the crushing properties are further assisted by the amount of silica fine particles. In addition, As is, for example, 0.5 area% or less.

[0137] Furthermore, in the toner used in the cartridge according to the present disclosure, when the average area ratio of the toner particle surface portion not covered with silica fine particles when observed with a scanning electron microscope (SEM) is defined as an exposure rate Bs, the exposure rate Bs is, for example, 55.0 area % or more and 80.0 area % or less.

[0138] From the viewpoint of showing more satisfactory crushing property while controlling the aggregation degree of the toner within an appropriate range, the exposure ratio Bs may be within the above range. The exposure ratio Bs is, for example, 60.0 area % or more and 75.0 area % or less.

[0139] Furthermore, in order to achieve the above-mentioned external additive amount and exposure rate Bs, the number average value of the major diameter of the silica fine particles is, for example, 30 nm or more and 150 nm or less and, for example, 50 nm or more and 120 nm or less.

[0140] Next, the crystalline resin component will be described.

[0141] The crystalline resin component refers to a material having an endothermic peak when measured using a differential scanning calorimeter (eg, "Q1000", manufactured by TA Instruments) in accordance with ASTM D3418-82. The crystalline resin component refers to an additive containing a component that crystallizes in the resin contained in the toner particles.

[0142] The domain of the crystalline resin component can be controlled by the compatibility between the resin contained in the toner and the crystalline resin component, and the cooling conditions in the toner production step and the annealing step for promoting crystallization of the crystalline resin component.

[0143] Specifically, the crystalline resin component refers to known waxes and crystalline resins. In particular, crystalline resin components such as ester waxes or crystalline polyesters are suitable. These materials are compatible with resins such as styrene acrylic resins and polyester resins used in toner particles, and undergo phase separation in the toner to form a crystalline state. Both high agglomeration and excellent crushing properties are exhibited by eliminating the exposure of these crystalline components.

[0144] The toner particles may contain a non-crystalline polyester. The weight average molecular weight of the non-crystalline polyester is, for example, 25,000 or more and 75,000 or less.

[0145] The non-crystalline polyester can form a resin structure by the ester group by exhibiting cohesive force due to the interaction caused by the polarity of the ester group. When the weight average molecular weight is 25,000 or more, the crushing property is excellent, and when the weight average molecular weight is 75,000 or less, the cohesive force is increased, which is excellent.

[0146] Furthermore, the acid value of the non-crystalline polyester is, for example, 10.0 mgKOH / g or more and 30.0 mgKOH / g or less.

[0147] When the acid value of the non-crystalline polyester is 10.0 mgKOH / g or more, the charging stability is excellent, and when the acid value thereof is 30.0 mgKOH / g or less, electrostatic aggregation is suppressed and the crushing property of the aggregate is excellent. Therefore, more excellent fogging suppression performance can be obtained by setting the acid value of the non-crystalline polyester to 10.0 mgKOH / g or more and 30.0 mgKOH / g or less.

[0148] The toner particles may contain boron, and the amount of boron present in the toner particles is, for example, 0.1 ppm by mass or more and 100 ppm by mass or less from the viewpoint of obtaining toner particles having high aggregating force and excellent crushing property.

[0149] This is considered to be because the boron atom interacts with a large number of ester groups of the polyester resin, since the boron atom has a high ionization potential and thus easily forms a covalent bond. As a result, it is presumed that the polyester having the boron atom forms a pseudo-crosslinked state, and elasticity can be imparted while maintaining the viscosity of the resin. In particular, in the case where boron forms an oxide, the oxide is amphoteric, and therefore it is likely to strongly interact with the carboxylic acid of the polyester and enter a state that is satisfactory in terms of toner aggregating force due to adhesion and crushing property due to elasticity of the polyester resin.

[0150] The amount of boron atoms present in the toner particles is, for example, 1.0 mass ppm or more and 30.0 mass ppm or less.

[0151] Toner components

[0152] Each component constituting the toner and a method of producing the toner will be described in more detail below.

[0153] Resin

[0154] The toner particles contain a resin, and the content of the resin is, for example, 50% by mass or more relative to the total amount of the resin component in the toner particles.

[0155] The resin is not particularly limited, and examples thereof include styrene acrylic resins, epoxy resins, polyester resins, polyurethane resins, polyamide resins, cellulose resins, polyether resins, and mixed resins and composite resins of these resins. Among them, styrene acrylic resins and polyester resins are suitable from the viewpoints of low cost, availability, and excellent low-temperature fixability.

[0156] Polyester resin

[0157] The polyester resin can be obtained by selecting a suitable compound from polycarboxylic acid, polyol, hydroxycarboxylic acid, and the like, combining the compounds, and synthesizing the combined compounds by a known method in the art such as an ester exchange method or a polycondensation method.

[0158] The polycarboxylic acid is a compound containing two or more carboxyl groups in one molecule. Among examples of the polycarboxylic acid, a dicarboxylic acid is a compound containing two carboxyl groups in one molecule and can be used.

[0159] Examples of dicarboxylic acids include oxalic acid, succinic acid, glutaric acid, maleic acid, adipic acid, β-methyladipic acid, azelaic acid, sebacic acid, nonanedicarboxylic acid, decanedicarboxylic acid, undecanedicarboxylic acid, dodecanedicarboxylic acid, fumaric acid, citraconic acid, diglycolic acid, cyclohexane-3,5-diene-1,2-carboxylic acid, hexahydroterephthalic acid, malonic acid, pimelic acid, suberic acid, phthalic acid, isophthalic acid, terephthalic acid, tetrachlorophthalic acid, chlorophthalic acid, nitrophthalic acid, p-carboxyphenylacetic acid, terephthalic acid, isophthalic acid, phthalic acid, diphenylacetic acid, diphenyl-p,p'-dicarboxylic acid, naphthalene-1,4-dicarboxylic acid, naphthalene-1,5-dicarboxylic acid, naphthalene-2,6-dicarboxylic acid, anthracenedicarboxylic acid, and cyclohexanedicarboxylic acid.

[0160] Examples of polycarboxylic acids other than dicarboxylic acids include trimellitic acid, trimesic acid, pyromellitic acid, naphthalenetricarboxylic acid, naphthalenetetracarboxylic acid, pyrenetricarboxylic acid, pyrenetetracarboxylic acid, itaconic acid, glutaconic acid, n-dodecylsuccinic acid, n-dodecenylsuccinic acid, isododecylsuccinic acid, isododecenylsuccinic acid, n-octylsuccinic acid, and n-octenylsuccinic acid. These can be used alone or in combination of two or more thereof.

[0161] The polyol is a compound containing two or more hydroxyl groups in one molecule. In an example of the polyol, a diol is a compound containing two hydroxyl groups in one molecule and can be used.

[0162] Specific examples of the polyol include ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, 1,3-hexanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, 1,12-dodecanediol, 1,13-tridecanediol, 1,14-tetradecanediol, 1,18-octadecanediol, 1,19-hexadecanediol, 2,3-hexadecanediol, 2,4-hexadecanediol, 2,5-hexadecanediol, 2,6-hexadecanediol, 2,7-hexadecanediol, 2,8-octadecanediol, 2,9-hexadecanediol, 2,8-hexadecanediol, 2,9-hexadecanediol, 2,10-hexadecanediol, 2,11-hexadecanediol, 2,12-dodecanediol, 2,13-hexadecanediol, 2,14-hexadecanediol, 2,8 ... diol, 1,14-eicosandiol, diethylene glycol, triethylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene ether glycol, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, 1,4-butene diol, neopentyl glycol, 1,4-cyclohexanediol, polytetramethylene glycol, hydrogenated bisphenol A, bisphenol A, bisphenol F, bisphenol S, and alkylene oxide (ethylene oxide, propylene oxide and butylene oxide) adducts of the above bisphenols.

[0163] Among them, alkylene glycol having 2 to 12 carbon atoms and alkylene oxide adducts of bisphenols are suitable, and a combination of alkylene oxide adducts of bisphenols and alkylene glycol having 2 to 12 carbon atoms is particularly suitable.

[0164] Examples of trivalent or higher polyols include glycerol, trimethylolethane, trimethylolpropane, pentaerythritol, hexamethylolmelamine, hexaethylolmelamine, tetramethylolbenzoguanamine, tetraethylolbenzoguanamine, sorbitol, trisphenol PA, phenol novolac, cresol novolac, and alkylene oxide adducts of the above trivalent or higher polyphenols. These may be used alone or in combination of two or more thereof.

[0165] Styrene acrylic resin

[0166] Examples of the styrene acrylic resin include homopolymers formed of the following polymerizable monomers, copolymers obtained by combining two or more homopolymers, and mixtures thereof.

[0167] Examples of the styrene acrylic resin include styrene monomers such as styrene, α-methylstyrene, β-methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, 2,4-dimethylstyrene, p-n-butylstyrene, p-tert-butylstyrene, p-n-hexylstyrene, p-n-octylstyrene, p-n-nonylstyrene, p-n-decylstyrene, p-n-dodecylstyrene, p-methoxystyrene, or p-phenylstyrene;

[0168] (Meth)acrylic monomers, such as methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, n-pentyl (meth)acrylate, n-hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, n-octyl (meth)acrylate, n-nonyl (meth)acrylate, cyclohexyl (meth)acrylate, benzyl (meth)acrylate, dimethylethyl (meth)phosphate, diethylethyl (meth)phosphate, dibutylethyl (meth)phosphate, 2-benzoyloxyethyl (meth)acrylate, (meth)acrylonitrile, 2-hydroxyethyl (meth)acrylate, (meth)acrylic acid, or maleic acid;

[0169] Vinyl ether monomers, such as vinyl methyl ether or vinyl isobutyl ether; vinyl ketone monomers, such as vinyl methyl ketone, vinyl ethyl ketone or vinyl isopropenyl ketone; and

[0170] Polyolefins, such as ethylene, propylene and butadiene.

[0171] As required, a multifunctional polymerizable monomer can be used as the styrene acrylic resin. Examples of multifunctional polymerizable monomers include diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, 2,2'-bis(4-((meth)acryloyloxydiethoxy)phenyl)propane, trimethylolpropane tri(meth)acrylate, tetramethylolmethane tetra(meth)acrylate, divinylbenzene, divinylnaphthalene, and divinyl ether.

[0172] Furthermore, a known chain transfer agent and a known polymerization inhibitor may be further added to the toner to control the degree of polymerization.

[0173] Examples of the polymerization initiator used for obtaining the styrene acrylic resin include organic peroxide-based initiators and azo-based polymerization initiators.

[0174] Examples of the organic peroxide-based initiator include benzoyl peroxide, lauroyl peroxide, di-α-cumyl peroxide, 2,5-dimethyl-2,5-bis(benzoylperoxy)hexane, bis(4-tert-butylcyclohexyl)peroxydicarbonate, 1,1-bis(tert-butylperoxy)cyclododecane, tert-butylperoxymaleic acid, bis(tert-butylperoxy)isophthalate, methyl ethyl ketone peroxide, tert-butyl peroxy-2-ethylhexanoate, diisopropyl peroxycarbonate, cumene hydroperoxide, 2,4-dichlorobenzoyl peroxide, and tert-butyl peroxypivalate.

[0175] Examples of the azo polymerization initiator include 2,2′-azobis-(2,4-dimethylvaleronitrile), 2,2′-azobisisobutyronitrile, 1,1′-azobis(cyclohexane-1-carbonitrile), 2,2′-azobis-4-methoxy-2,4-dimethylvaleronitrile, azobismethylbutyronitrile, and 2,2′-azobis-(methylisobutyrate).

[0176] Furthermore, as the polymerization initiator, a redox initiator obtained by combining an oxidizing substance and a reducing substance may also be used.

[0177] Examples of the oxidizing substance include hydrogen peroxide, inorganic peroxides of persulfates (sodium salts, potassium salts or ammonium salts), and oxidizing metal salts of tetravalent cerium salts.

[0178] Examples of reducing substances include reducing metal salts (ferrous salts, copper salts or trivalent chromium salts); ammonia; lower amines (amines having 1 or more and 6 or less carbon atoms, such as methylamine or ethylamine); amino compounds such as hydroxylamine; reducing sulfur compounds such as sodium thiosulfate, sodium dithionite, sodium bisulfite, sodium sulfite or sodium formaldehyde sulfoxylate; lower alcohols (having 1 or more and 6 or less carbon atoms); ascorbic acid or its salts; and lower aldehydes (having 1 or more and 6 or less carbon atoms).

[0179] The polymerization initiator is selected with reference to the 10-hour half-life temperature, and is used alone or in the form of a mixture.

[0180] The amount of the polymerization initiator added varies depending on the target degree of polymerization, but is usually 0.5 parts by mass or more and 20.0 parts by mass or less relative to 100.0 parts by mass of the polymerizable monomer.

[0181] Release agent

[0182] Known waxes can be used in toners as release agents.

[0183] Specific examples thereof include petroleum waxes such as paraffin, microcrystalline wax and vaseline and derivatives thereof, montan wax and derivatives thereof, hydrocarbon waxes obtained by using a Fischer-Tropsch process and derivatives thereof, polyolefin waxes such as polyethylene and derivatives thereof, and natural waxes such as carnauba wax and candelilla wax and derivatives thereof, and derivatives include oxides, block copolymers with vinyl monomers, and graft modified products.

[0184] In addition, examples of waxes include alcohols such as higher aliphatic alcohols; fatty acids such as stearic acid and palmitic acid, acid amides, esters and ketones thereof; hydrogenated castor oil and derivatives thereof, plant waxes and animal waxes. These may be used alone or in combination.

[0185] Among them, from the viewpoint that developability and transferability tend to be improved, polyolefin, hydrocarbon wax obtained by using the Fischer-Tropsch process, or petroleum-based wax can be used. In addition, an antioxidant can be added to these waxes within a range that does not affect the characteristics of the toner.

[0186] Furthermore, from the viewpoint of phase separation property and crystallization temperature with respect to the resin, suitable examples thereof include higher fatty acid esters such as behenyl behenate and dibehenyl sebacate.

[0187] The content of the release agent is, for example, 1.0 part by mass or more and 30.0 parts by mass or less relative to 100.0 parts by mass of the resin.

[0188] The melting point of the release agent is, for example, 30° C. to 120° C., and for example, 60° C. to 100° C. When a release agent having a melting point of 30° C. to 120° C. is used, the release effect is effectively exerted and a wider fixing area is ensured.

[0189] Plasticizers

[0190] A crystalline plasticizer may be used in the toner to improve sharp melting properties. The plasticizer is not particularly limited, and known plasticizers for toner as described below may be used.

[0191] Examples of plasticizers include esters of monohydric alcohols such as behenyl behenate, stearyl stearate and palmityl palmitate and aliphatic carboxylic acids, or esters of monohydric carboxylic acids and aliphatic alcohols; esters of dihydric alcohols such as ethylene glycol distearate, dibehenyl sebacate and hexylene glycol dibehenate and aliphatic carboxylic acids, or esters of dihydric carboxylic acids and aliphatic alcohols; esters of trihydric alcohols such as trimethoxyglyceryl and aliphatic carboxylic acids, or esters of trihydric carboxylic acids and aliphatic alcohols; esters of trihydric alcohols such as glyceryl tribehenate and aliphatic carboxylic acids, or esters of trihydric carboxylic acids and aliphatic alcohols; esters of dihydric alcohols such as ethylene glycol distearate, dibehenyl sebacate and hexylene glycol dibehenate and aliphatic carboxylic acids, or esters of dihydric ... trihydric alcohols; esters of dihydric alcohols such as ethylene glycol distearate, dibehenyl sebacate and hexylene glycol dibehenate and aliphatic carboxylic acids, or esters of dihydric alcohols; esters of dihydric alcohols such as ethylene glycol distearate, dibehenyl sebacate and hexylene glycol dibehenate and aliphatic carboxylic acids, or ester Such as esters of tetrahydric alcohols and aliphatic carboxylic acids, or esters of tetrahydric carboxylic acids and aliphatic alcohols, such as pentaerythritol tetrastearate and pentaerythritol tetrapalmitate; esters of hexahydric alcohols and aliphatic carboxylic acids, or esters of hexahydric carboxylic acids and aliphatic alcohols, such as dipentaerythritol hexastearate and dipentaerythritol palmitate; esters of polyhydric alcohols and aliphatic carboxylic acids, or esters of polyhydric carboxylic acids and aliphatic alcohols, such as polyglycerol behenate; and natural ester waxes such as carnauba wax and rice wax. These can be used alone or in combination.

[0192] Colorants

[0193] The toner particles may contain a colorant. A known pigment or a known dye may be used as the colorant. From the viewpoint of excellent weather resistance, a pigment is suitable as the colorant.

[0194] Examples of cyan colorants include copper phthalocyanine compounds and derivatives thereof, anthraquinone compounds, and basic dye lake compounds. Specific examples thereof include CI Pigment Blue 1, 7, 15, 15:1, 15:2, 15:3, 15:4, 60, 62, and 66.

[0195] Examples of magenta colorants include condensed azo compounds, diketopyrrolopyrrole compounds, anthraquinone compounds, quinacridone compounds, basic dye lake compounds, naphthol compounds, benzimidazolone compounds, thioindigo compounds, and perylene compounds. Specific examples thereof include CI Pigment Red 2, 3, 5, 6, 7, 23, 48:2, 48:3, 48:4, 57:1, 81:1, 122, 144, 146, 150, 166, 169, 177, 184, 185, 202, 206, 220, 221, and 254, and CI Pigment Violet 19.

[0196] Examples of yellow colorants include condensed azo compounds, isoindolinone compounds, anthraquinone compounds, azo metal complexes, methine compounds, and allylamide compounds. Specific examples thereof include CI Pigment Yellow 12, 13, 14, 15, 17, 62, 74, 83, 93, 94, 95, 97, 109, 110, 111, 120, 127, 128, 129, 147, 151, 154, 155, 168, 174, 175, 176, 180, 181, 185, 191, and 194.

[0197] Examples of the black colorant include colorants toned to black using the above-mentioned yellow-based colorant, magenta-based colorant, and cyan-based colorant, and carbon black.

[0198] These colorants may be used alone or in the form of a mixture, and may also be used as a solid solution.

[0199] The content of the colorant is, for example, 1.0 part by mass or more and 20.0 parts by mass or less relative to 100.00 parts by mass of the resin.

[0200] Charge control agent and charge control resin

[0201] The toner particles may contain a charge control agent or a charge control resin.

[0202] As the charge control agent, a known charge control agent can be used, and in particular, a charge control agent having a high friction charging speed and capable of stably maintaining a constant friction charging amount is suitable. In addition, in the case of producing toner particles by suspension polymerization, a charge control agent having low polymerization inhibition and substantially containing no soluble matter in an aqueous medium is particularly suitable.

[0203] Examples of charge control agents for controlling the negative charge of the colorant include monoazo metal compounds, acetylacetone metal compounds, aromatic hydroxycarboxylic acid metal compounds, aromatic dicarboxylic acid metal compounds, hydroxycarboxylic acid metal compounds, dicarboxylic acid metal compounds, aromatic hydroxycarboxylic acids, aromatic monocarboxylic acids, aromatic polycarboxylic acids and their metal salts, acid anhydrides, esters, phenol derivatives such as bisphenols, urea derivatives, metal-containing salicylic acid compounds, metal-containing naphthoic acid compounds, boron compounds, quaternary ammonium salts, calixarenes and charge control resins.

[0204] Examples of charge control resins include polymers or copolymers containing sulfonic acid groups, sulfonic acid radicals or sulfonic acid ester groups. In terms of copolymerization ratio, the polymer containing sulfonic acid groups, sulfonic acid radicals or sulfonic acid ester groups is particularly suitably a polymer containing 2% by mass or more of acrylamide monomers containing sulfonic acid groups or methacrylamide monomers containing sulfonic acid groups, and more suitably a polymer containing 5% by mass or more of acrylamide monomers containing sulfonic acid groups or methacrylamide monomers containing sulfonic acid groups.

[0205] The glass transition temperature (Tg) of the charge control resin is, for example, 35° C. or more and 90° C. or less, the peak molecular weight (Mp) is 10,000 or more and 30,000 or less, and the weight average molecular weight (Mw) is 25,000 or more and 50,000 or less. In the case of using such a charge control resin, suitable friction charging characteristics can be imparted to the toner particles without affecting the thermal characteristics required for the toner particles. In addition, in the case where the charge control resin contains a sulfonic acid group, for example, the dispersibility of the charge control resin in the polymerizable monomer composition and the dispersibility of the colorant are improved, and the coloring power, transparency and friction charging characteristics can be improved.

[0206] These charge control agents or charge control resins may be used each alone or added in combination of two or more thereof.

[0207] The amount of the charge control agent or the charge control resin added is, for example, 0.01 parts by mass or more and 20.0 parts by mass or less, and for example, 0.5 parts by mass or more and 10.0 parts by mass or less, relative to 100.0 parts by mass of the resin.

[0208] Silica fine particles

[0209] From the viewpoint of being easy to control the shape to have a large number of concave parts, dry process silica is suitable as a silica fine particle used as an external additive in the toner according to the present disclosure. Dry process silica is formed by a halogenated silicon compound as a raw material, etc. As a halogenated silicon compound, silicon tetrachloride is used, but silanes such as methyltrichlorosilane and trichlorosilane can be used alone, or silicon tetrachloride and silanes can be used as raw materials in a mixed state. After the raw material is evaporated, the target silica is obtained by reacting the raw material with water generated as an intermediate in a so-called flame hydrolysis reaction in an oxyhydrogen flame. For example, a thermal decomposition oxidation reaction of silicon tetrachloride gas in oxygen and hydrogen is used, and the reaction formula is as follows.

[0210] SiCl4+2H2+O2→SiO2+4HCl

[0211] Hereinafter, a method for producing silica will be described.

[0212] Oxygen is supplied to the burner to ignite the ignition burner, hydrogen is supplied to the burner to form a flame, and silicon tetrachloride as a raw material is added thereto to be gasified. A flame hydrolysis reaction is performed, and the generated silicon dioxide powder is recovered.

[0213] By appropriately changing the silicon tetrachloride flow rate, oxygen supply flow rate, hydrogen supply flow rate and the residence time of silicon dioxide in the flame, the average particle size and shape can be arbitrarily adjusted, thereby preparing silicon dioxide particles in a shape with a large number of recesses. The shape with a large number of recesses can be controlled by transferring the obtained silicon dioxide powder to an electric furnace, spreading the silicon dioxide powder in a thin layer and performing a heat treatment to sinter the silicon dioxide powder. When the silicon dioxide powder is sintered, the agglomeration strength of the silicon dioxide particles is improved.

[0214] Furthermore, the silica particles used in the present disclosure may be subjected to surface treatment such as hydrophobization treatment or silicone oil treatment.

[0215] The hydrophobization method is carried out by chemically treating with an organosilicon compound that reacts with or physically adsorbs on silica to impart hydrophobicity. As a suitable method, silica produced by gas phase oxidation of a halogenated silicon compound is treated with an organosilicon compound.

[0216] Examples of such organosilicon compounds include

[0217] Hexamethyldisilazane, trimethylsilane, trimethylchlorosilane, trimethylethoxysilane, dimethyldichlorosilane, methyltrichlorosilane, allyldimethylchlorosilane, allylphenyldichlorosilane, benzyldimethylchlorosilane,

[0218] Bromomethyldimethylchlorosilane, α-chloroethyltrichlorosilane, β-chloroethyltrichlorosilane, chloromethyldimethylchlorosilane, triorganosilylmercaptan, trimethylsilylmercaptan, triorganosilylacrylate,

[0219] Vinyldimethylacetoxysilane, dimethylethoxysilane, dimethyldimethoxysilane, diphenyldiethoxysilane, 1-hexamethyldisiloxane,

[0220] 1,3-divinyltetramethyldisiloxane, 1,3-diphenyltetramethyldisiloxane, and dimethylpolysiloxane.

[0221] These may be used alone or in the form of a mixture of two or more thereof.

[0222] In the silicone oil-treated silica, as the silicone oil, a silicone oil having a viscosity of 30 mm at 25° C. can be used. 2 / s or more and 1000mm 2 / s or less. Examples thereof include dimethyl silicone oil, methylphenyl silicone oil, α-methylstyrene-modified silicone oil, chlorophenyl silicone oil, and fluorine-modified silicone oil.

[0223] Examples of methods for performing silicone oil treatment include

[0224] A method of directly mixing silicone oil with silica treated with a silane coupling agent using a mixer such as a Henschel mixer,

[0225] A method of spraying silicone oil onto silica used as a base and a method of dissolving or dispersing silicone oil in an appropriate solvent, adding silica thereto, mixing the mixture and removing the solvent.

[0226] In the silicone oil-treated silica, the silicone oil-treated silica can be heated in an inert gas at a temperature of 200° C. or higher (eg, 250° C. or higher), and the coating on the surface is stabilized. Suitable examples of the silane coupling agent include hexamethyldisilazane (HMDS).

[0227] The amount of the silica fine particles added is 1.5 parts by mass or more and 5.0 parts by mass or less relative to 100 parts by mass of the toner particles.

[0228] The fixed state of the external additive and the covering state of the toner particles with the external additive can be arbitrarily controlled by adjusting the rotation speed (rpm) of the stirring blade provided in the external adding machine and the external adding time as external adding conditions.

[0229] In order to make the toner particles more firmly fixed, it is effective to increase the rotation speed and extend the external addition time, and in particular, the fixing strength can be further improved by increasing the rotation speed. In addition, since the external additive particles with a small particle size form aggregates, the toner particles are covered with the external additive while the crushing process is performed by controlling the external addition conditions. The crushing property can be improved by increasing the rotation speed and extending the external addition time, but in order to further promote the crushing while suppressing the fixing strength, it is effective to reduce the rotation speed and extend the external addition time.

[0230] Method for producing toner

[0231] The method of producing the toner is not particularly limited, and the toner may be produced by using a known method such as a pulverization method, a suspension polymerization method, a dissolution suspension method, an emulsion aggregation method, or a dispersion polymerization method. Here, the toner may be produced by an emulsion aggregation method.

[0232] The method for producing a toner comprises steps (1) to (3) in the following order:

[0233] (1) a dispersing step of preparing a resin fine particle dispersion liquid containing a resin,

[0234] (2) an aggregation step of aggregating the resin fine particles contained in the resin fine particle dispersion to form aggregates, and

[0235] (3) a fusing step of heating and fusing the aggregate,

[0236] Wherein, a boric acid source is added in at least one of the aggregation step and the fusion step.

[0237] Furthermore, during or after the fusing step, steps (4) to (6) may be arranged in the following order:

[0238] (4) a step of increasing the temperature and heating the aggregate to form a spheroid,

[0239] (5) a cooling step of cooling the aggregate at a cooling rate of 0.1°C / sec or more, and

[0240] (6) An annealing step in which the aggregate is heated and maintained at a temperature above the crystallization temperature of the resin or above the glass transition temperature of the resin.

[0241] From the viewpoint of controlling the toner shape and easily dispersing the boric acid uniformly near the toner surface, the toner may be produced by the emulsion aggregation method. Hereinafter, the emulsion aggregation method will be described in detail.

[0242] Emulsion aggregation method

[0243] The emulsion aggregation method is a method for producing colorant particles by pre-preparing an aqueous dispersion of fine particles formed by constituent materials of colorant particles that are relatively small relative to a target particle size, aggregating the fine particles in an aqueous medium until the particle size of the particles reaches the particle size of the colorant particles, and fusing the resin by heating or the like.

[0244] That is, according to the emulsion aggregation method, colorant particles are produced by performing the following steps: a dispersion step of preparing a fine particle dispersion formed from a constituent material of the colorant particles, an aggregation step of controlling the particle size until the particle size of the particles reaches the particle size of the colorant particles, a fusion step of subjecting the resin contained in the obtained aggregated particles to melt adhesion, a spheroidization step of heating the particles so that the particles are melted and the surface shape of the colorant is controlled, a subsequent cooling step, a metal removal step of separating the obtained colorant by filtering and removing excess polyvalent metal ions, a filtration washing step of washing the colorant with ion exchange water or the like, and a step of removing moisture from the washed colorant particles and drying the colorant particles.

[0245] Step of preparing a dispersion of resin fine particles (dispersion step)

[0246] The resin fine particle dispersion can be prepared by a known method, but the present disclosure is not limited thereto. Examples of the known methods include an emulsion polymerization method, a self-emulsification method, a phase inversion emulsification method in which an aqueous medium is added to a resin solution dissolved in an organic solvent to emulsify the resin, and a forced emulsification method in which a high temperature treatment is performed in an aqueous medium to force emulsify the resin without using an organic solvent.

[0247] Specifically, the resin is dissolved in an organic solvent that can dissolve the resin, and a surfactant and an alkaline compound are added thereto. In this case, when the resin is a crystalline resin with a melting point, the resin can be dissolved by heating above the melting point. Next, while stirring the mixture with a homogenizer, an aqueous medium is slowly added to the mixture so that the resin fine particles are precipitated. Thereafter, the solvent is removed by heating the mixture or reducing pressure, thereby preparing an aqueous dispersion of the resin fine particles. Any organic solvent can be used as the organic solvent for dissolving the resin, as long as the organic solvent can dissolve the resin, but, from the viewpoint of suppressing the generation of coarse powder, an organic solvent that forms a homogeneous phase with water, such as toluene, can be used.

[0248] The surfactant used for emulsification is not particularly limited, and examples thereof include anionic surfactants such as sulfate ester surfactants, sulfonate surfactants, carboxylate surfactants, phosphate surfactants, or soap surfactants; cationic surfactants such as amine salt surfactants or quaternary ammonium salt surfactants; and nonionic surfactants such as polyethylene glycol surfactants, alkylphenol ethylene oxide adduct surfactants, or polyol surfactants. The surfactant may be used alone or in combination of two or more thereof.

[0249] Examples of the basic compound used in the dispersion step include inorganic bases such as sodium hydroxide or potassium hydroxide; and organic bases such as ammonia, triethylamine, trimethylamine, dimethylaminoethanol or diethylaminoethanol. The basic compound may be used alone or in combination of two or more thereof.

[0250] In addition, the 50% particle size (D50) of the resin fine particles based on volume distribution in the aqueous dispersion of the resin fine particles is, for example, in the range of 0.05 μm to 1.0 μm, and, for example, in the range of 0.05 μm to 0.4 μm. Toner particles having an appropriate volume average particle size of 3 μm to 10 μm are easily obtained by adjusting the 50% particle size (D50) based on volume distribution thereof to be within the above range.

[0251] In addition, the 50% particle diameter (D50) of the particles based on volume distribution is measured using a dynamic light scattering particle size distribution meter NANOTRACUPA-EX150 (manufactured by Nikkiso Co., Ltd.).

[0252] Colorant fine particle dispersion

[0253] As required, colorant fine particle dispersion can be used. Colorant fine particle dispersion can be prepared by following known method, but the present disclosure is not limited thereto. Colorant fine particle dispersion can be prepared by using known mixer such as stirrer, emulsifier or disperser to mix colorant, aqueous medium and dispersant. As the dispersant used here, known dispersant such as surfactant or polymer dispersant can be used. Two kinds of dispersants (surfactant and polymer dispersant) can be removed in the following cleaning step, but, from the viewpoint of cleaning efficiency, surfactant is suitable.

[0254] Examples of surfactants include anionic surfactants such as sulfate ester surfactants, sulfonate surfactants, phosphate ester surfactants or soap surfactants; cationic surfactants such as amine salt surfactants or quaternary ammonium salt surfactants; and nonionic surfactants such as polyethylene glycol surfactants, alkylphenol ethylene oxide adduct surfactants or polyol surfactants. Among them, nonionic surfactants or anionic surfactants are suitable. In addition, nonionic surfactants and anionic surfactants can be used in combination. Surfactants can be used alone or in combination of two or more thereof. The concentration of the surfactant in the aqueous medium is, for example, in the range of 0.5 mass % to 5 mass %.

[0255] The content of the colorant fine particles in the colorant fine particle dispersion liquid is not particularly limited, but is, for example, in the range of 1% by mass to 30% by mass relative to the total mass of the colorant fine particle dispersion liquid.

[0256] In the dispersed particle size of the colorant fine particles in the aqueous dispersion of the colorant, from the viewpoint of the dispersibility of the colorant in the finally obtained toner, the 50% particle size (D50) based on the volume distribution is, for example, 0.5 μm or less. In addition, for the same reason, the 90% particle size (D90) based on the volume distribution is, for example, 2 μm or less. In addition, the dispersed particle size of the colorant fine particles dispersed in the aqueous medium is measured using a dynamic light scattering particle size distribution meter (NANOTRAC UPA-EX150, manufactured by Nikkiso Co., Ltd.).

[0257] Examples of mixers such as known stirrers, emulsifiers or dispersers used when dispersing the colorant in an aqueous medium include ultrasonic homogenizers, jet mills, pressure homogenizers, colloid mills, ball mills, sand mills and paint stirrers. These can be used alone or in combination.

[0258] Release agent (aliphatic hydrocarbon compound) fine particle dispersion

[0259] As necessary, a release agent fine particle dispersion may be used. The release agent fine particle dispersion may be prepared by a known method described below, but the present disclosure is not limited thereto.

[0260] The releasing agent fine particle dispersion can be prepared by adding the releasing agent to an aqueous medium containing a surfactant, heating the mixture at a temperature above the melting point of the releasing agent, dispersing the releasing agent in the form of particles using a homogenizer having a strong shearing ability (e.g., "CLEARMIX W-MOTION", manufactured by M Technique Co., Ltd.) or a pressure jet type disperser (e.g., "GAULIN homogenizer", manufactured by Gaulin Corporation), and cooling the mixture at a temperature below the melting point of the releasing agent.

[0261] In the dispersed particle size of the release agent fine particle dispersion in the aqueous dispersion of the release agent, the 50% particle size (D50) based on volume distribution is, for example, in the range of 0.03 μm to 1.0 μm, and, for example, in the range of 0.1 μm to 0.5 μm. In addition, coarse particles having a particle size of 1 μm or more may not exist.

[0262] When the dispersion particle size of the release agent fine particle dispersion liquid is within the above range, the release agent can exist in a finely dispersed state in the toner, the oozing effect during fixing can be maximized, and satisfactory separation can be obtained. In addition, the dispersion particle size of the release agent fine particle dispersion liquid dispersed in the aqueous medium can be measured using a dynamic light scattering particle size distribution meter NANOTRAC UPA-EX150 (manufactured by Nikkiso Co., Ltd.).

[0263] Mixing Steps

[0264] In the mixing step, a mixed liquid is prepared by mixing the resin fine particle dispersion with at least one of the releasing agent fine particle dispersion and the colorant fine particle dispersion as required. The mixed liquid can be prepared by using a known mixing device such as a homogenizer or a mixer.

[0265] Step of forming aggregate particles (aggregation step)

[0266] In the aggregation step, the fine particles contained in the mixed solution prepared in the mixing step are aggregated to form aggregates having a target particle size. Here, an aggregating agent is added and mixed into the mixture, and at least one of heating and mechanical force is appropriately applied to the mixture as needed to form aggregates in which the resin fine particles are aggregated with at least one of the release agent fine particles and the colorant fine particles.

[0267] Examples of the aggregating agent include organic aggregating agents such as quaternary salt cationic surfactants or polyethyleneimine; inorganic metal salts such as sodium sulfate, sodium nitrate, sodium chloride, calcium chloride or calcium nitrate; inorganic ammonium salts such as ammonium sulfate, ammonium chloride or ammonium nitrate; and inorganic aggregating agents such as divalent or higher metal complexes. In addition, an acid may be added to the mixed solution so that the pH is lowered and the particles are softly aggregated, and as the acid, sulfuric acid or nitric acid or the like may be used.

[0268] The aggregating agent can be added to the mixed solution in any form of a dry powder or an aqueous solution dissolved in an aqueous medium, but the aggregating agent can be added in the form of an aqueous solution so that the particles are uniformly aggregated. In addition, the aggregating agent can be added and mixed into the mixed solution at a temperature below the glass transition temperature or melting point of the resin contained in the mixed solution. When the aggregating agent is mixed into the mixed solution under the above temperature conditions, relatively uniform aggregation is performed. The aggregating agent can be mixed into the mixed solution using a known mixing device such as a homogenizer or a mixer. The aggregation step is a step of forming aggregates having a toner particle size in an aqueous medium. The volume average particle size of the aggregates produced in the aggregation step is, for example, in the range of 3μm to 10μm. The volume average particle size can be measured by the Coulter method using a particle size distribution analyzer (COULTER Multisizer III: manufactured by BeckmanCoulter, Inc.).

[0269] A shell forming step of further adding resin fine particles containing a resin for a shell to the dispersion containing the aggregates and aggregating the particles to form aggregates having a shell

[0270] A shell forming step of forming a shell by further adding fine resin particles containing a resin for a shell and aggregating the particles may be provided after forming aggregated particles (core particles) in the aggregation step. That is, the toner particles may include core particles containing a binder resin and a shell on the surface of the core particles. As the resin for the shell, the same resin as the binder resin may be used, or other resins may be used. The amount of the resin for the shell added is, for example, 5 parts by mass or more and 40 parts by mass or less relative to 100 parts by mass of the binder resin contained in the core particles, and, for example, 10 parts by mass or more and 30 parts by mass or less.

[0271] In this case, in order to make the toner particles easily contain boron, a boron compound may be added to the dispersion liquid containing the aggregates together with the resin fine particles containing the resin for the shell in the shell forming step.

[0272] The boron compound may be boric acid or a compound that can be changed to boric acid by controlling the pH in the production of the toner. Examples thereof include at least one selected from the group consisting of boric acid, borax, organic boric acid, borate and boric ester. For example, the pH may be controlled by adding a boric acid source to the mixed solution so that the aggregate contains boric acid. The shell forming step may be performed by controlling the pH under acidic conditions in the aggregation step.

[0273] Boric acid may be present in the aggregate in an unsubstituted state. At least one selected from the group consisting of boric acid and borax is suitable as the boric acid source. In the case of producing the toner in an aqueous medium, from the viewpoint of reactivity and production stability, a borate may be added to the mixed solution as a boric acid source. Specifically, the boric acid source more suitably includes at least one selected from the group consisting of sodium tetraborate, borax and ammonium borate, and further more suitably includes borax.

[0274] Borax is represented by sodium tetraborate decahydrate (Na2B4O7) and becomes boric acid in an acidic aqueous solution, so when used for an aqueous medium under an acidic environment, borax can be used. According to the addition method, borax can be added in any form of a dry powder or an aqueous solution dissolved in an aqueous medium, but borax can be added in the form of an aqueous solution so that the particles are uniformly aggregated. The concentration of the aqueous solution can be appropriately changed depending on the concentration to be contained in the toner, and is, for example, in the range of 1 mass % to 20 mass %. The pH can be controlled to be in an acidic condition before, during, or after the addition of borax, so that the borax becomes boric acid. The pH can be controlled, for example, in the range of 1.5 to 5.0 and, for example, in the range of 2.0 to 4.0.

[0275] Step of obtaining a dispersion liquid containing toner particles (fusion step)

[0276] In the fusion step, first, while stirring the dispersion containing the aggregates obtained in the aggregation step in the same manner as in the aggregation step, aggregation is terminated by adding an aggregation terminator capable of adjusting pH, such as an alkali, a chelate compound, or an inorganic salt compound such as sodium chloride.

[0277] The dispersion state of the aggregated particles in the dispersion liquid is stabilized by the action of the aggregation terminator, and the mixed liquid is heated at a temperature above the glass transition temperature or melting point of the resin to fuse the aggregated particles, thereby preparing particles having a desired particle size. In addition, the 50% particle size (D50) based on volume distribution of the toner particles is, for example, in the range of 3 μm to 10 μm.

[0278] Step of obtaining a desired toner surface shape (spheroidization step)

[0279] A spheroidization step of further increasing the temperature and maintaining the temperature until the toner particles have a desired circularity or surface shape may be performed during or after the fusing step. The temperature of a specific spheroidization step is, for example, 90° C. or higher, for example, 92° C. or higher, and, for example, 95° C. or lower. The heating time in the spheroidization step is, for example, 3 hours or more, 5 hours or more, or 8 hours or more. In this step, hydrogen bonds derived from boric acid are likely to be formed in the toner particles.

[0280] Cooling Steps

[0281] A cooling step of lowering the temperature of the dispersion containing the obtained toner particles to a temperature lower than the crystallization temperature or glass transition temperature of the resin and the crystalline resin component can be performed by controlling the cooling rate after the spheroidization step. Changes in the domain shape accompanying the crystallization of the crystalline resin component can be suppressed by performing the cooling step. As a result, the proportion of the domain area of ​​the crystalline resin component near the surface of the toner particles is easily controlled.

[0282] A specific cooling rate is 0.1° C. / second or more, for example, 0.5° C. / second or more, for example, 2° C. / second or more, and for example, 4° C. / second or more.

[0283] Annealing step

[0284] After the cooling step, an annealing step of heating the mixed solution at a temperature above the crystallization temperature or glass transition temperature of the resin or, if the mixed solution contains a release agent, at a temperature below the crystallization temperature of the release agent and maintaining the temperature may be performed.

[0285] The crystalline resin component compatible with the resin of the toner particles is crystallized by performing the annealing step and the change in the domain shape can be further suppressed.

[0286] Post-processing steps

[0287] In the method of producing the toner, post-processing steps such as a washing step, a solid-liquid separation step, a drying step, etc. may be performed, and toner particles in a dry state may be obtained by performing the post-processing steps.

[0288] External Addition Steps

[0289] In the external adding step, silica fine particles are externally added to the toner particles obtained in the drying step.

[0290] The fixed state of the external additive and the covering state of the toner particles with the external additive can be arbitrarily controlled by adjusting the rotation speed (rpm) of the stirring blade provided in the external adding machine and the external adding time as external adding conditions.

[0291] In order to make the toner particles more firmly fixed, it is effective to increase the rotation speed and extend the external addition time, and in particular, the fixing strength can be further improved by increasing the rotation speed. In addition, since the external additive particles with a small particle size form aggregates, the toner particles are covered with the external additive while the crushing process is performed by controlling the external addition conditions. The crushing property can be improved by increasing the rotation speed and extending the external addition time, but in order to further promote the crushing while suppressing the fixing strength, it is effective to reduce the rotation speed and extend the external addition time.

[0292] Methods for measuring various physical properties

[0293] Next, a method of measuring various physical properties according to the present disclosure will be described.

[0294] Measurement of weight average particle size (D4) and number average particle size (D1) of toner or toner particles

[0295] The weight average particle diameter (D4) and number average particle diameter (D1) of the toner or toner particles are measured using a precision particle size distribution measuring device "COULTER COUNTER Multisizer 3" (registered trademark, manufactured by Beckman Coulter, Inc.) provided with an orifice tube having a diameter of 100 μm by a pore resistance method and dedicated software "BECKMAN COULTER Multisizer 3 Version 3.51" (manufactured by Beckman Coulter, Inc.) attached to the device through 25,000 effective measurement channels, and calculated by analyzing the measurement data.

[0296] As the electrolyte solution used for measurement, an electrolyte solution obtained by dissolving special grade sodium chloride in ion exchange water and adjusting the concentration thereof to about 1% by mass, such as “ISOTON II” (manufactured by Beckman Coulter, Inc.) can be used.

[0297] Furthermore, prior to measurement and analysis, the dedicated software was set in the following manner.

[0298] In the dedicated software "Change Standard Measurement Method (SOM) Interface", the total count in the control mode was set to 50,000 particles, the number of measurements was set to 1, and the value obtained by using "Standard Particles 10.0 μm" (manufactured by Beckman Coulter, Inc.) was set as the Kd value. The threshold and noise level were automatically set by pressing the measurement button of the threshold / noise level. In addition, the current was set to 1600 μA, the gain was set to 2, the electrolyte solution was set to ISOTON II, and the mouth tube flushing after measurement was checked.

[0299] In the dedicated software "Pulse to Particle Size Conversion Setting Screen", the element interval was set to the logarithmic particle size, the particle size element was set to 256 particle size elements, and the particle size range was set to 2 μm or more and 60 μm or less.

[0300] The specific measurement method is as follows.

[0301] (1) About 200 ml of electrolyte solution was placed in a 250 ml round-bottom glass beaker dedicated to Multisizer 3 and placed on the sample stage, and the solution was stirred in a counterclockwise direction at 24 rpm with a stirring rod. In addition, dirt and bubbles in the nozzle were removed by the dedicated software "Nozzle Rinse".

[0302] (2) A 100-ml flat-bottom glass beaker was charged with about 30 ml of the electrolyte solution, and about 0.3 ml of a dilution obtained by diluting "Contaminon N" (a 10% by mass aqueous solution of a neutral detergent for cleaning precision measuring instruments having a pH of 7, formed of a nonionic surfactant, anionic surfactant and an organic builder, manufactured by Wako Pure Chemical Industries, Ltd.) with ion-exchanged water to 3 times by mass was added thereto as a dispersant.

[0303] (3) A predetermined amount of ion-exchanged water was poured into a water tank of an ultrasonic disperser "Ultrasonic Dispersion System Tetoral 150" having two built-in oscillators with an oscillation frequency of 50 kHz and a power output of 120 W, which was provided with a phase shift of 180 degrees, and about 2 ml of Contaminon N was added to the water tank.

[0304] (4) The beaker of item (2) is placed in the beaker fixing hole of the ultrasonic disperser, and the ultrasonic disperser is started. In addition, the height position of the beaker is adjusted so that the resonance state of the liquid surface of the electrolyte solution in the beaker is maximized.

[0305] (5) The electrolyte solution in the beaker of item (4) is irradiated with ultrasonic waves, and about 10 mg of toner or toner particles are gradually added to the electrolyte solution and dispersed therein. Furthermore, the ultrasonic dispersion treatment is continued for another 60 seconds. Furthermore, in the ultrasonic dispersion treatment, the water temperature in the water tank is appropriately adjusted to 10° C. or more and 40° C. or less.

[0306] (6) The electrolyte solution of item (5) in which the toner or toner particles are dispersed is added dropwise to the round-bottom beaker of item (1) set in the sample stage using a pipette, and the measurement concentration is adjusted to about 5%. Furthermore, the measurement is performed until the number of measured particles reaches 50,000.

[0307] (7) The weight average particle diameter (D4) is calculated by analyzing the measurement data using the dedicated software attached to the device. In addition, when the dedicated software is set to graph / volume %, the "average diameter" of the analysis / volume statistics (arithmetic mean) interface is the weight average particle diameter (D4), and when the dedicated software is set to graph / number %, the "average diameter" of the "analysis / number statistics (arithmetic mean)" interface is the number average particle diameter (D1).

[0308] Method for measuring the amount of elements in toner

[0309] The fluorescent X-ray of each element is measured in accordance with JIS K 0119-1969, and the specific method thereof is as follows.

[0310] A wavelength dispersive X-ray fluorescence analyzer "Axios" (manufactured by PANalytical) was used as a measuring device, and a dedicated software "SuperQ Version 4.0F" (manufactured by PANalytical) attached to the device for setting measurement conditions and analyzing measurement data was used. In addition, Rh was used as the anode of the X-ray tube, the measurement was performed in a vacuum atmosphere, the measurement diameter (collimator mask diameter) was set to 27 mm, and the measurement time was set to 10 seconds. In addition, light elements were measured by detection with a proportional counter (PC), and heavy elements were measured by detection with a scintillation counter (SC).

[0311] As a measurement sample, a pellet having a thickness of about 2 mm and a diameter of about 39 mm is used, which is formed by pouring about 4 g of the toner into a dedicated aluminum pan for pressing, flattening its surface, and pressing the surface at 20 MPa for 60 seconds using a tablet forming press "BRE-32" (manufactured by Maekawa Testing Machine MFG Co., Ltd.).

[0312] The measurement was performed under the above conditions, the element was identified based on the peak position of the obtained X-ray, and the concentration thereof was calculated from the count rate (unit: cps) which is the number of X-ray photons per unit time.

[0313] Quantification of SiO2 in toner

[0314] Silica (SiO2) fine powder was added to the toner particles and fully mixed into the toner particles using a coffee grinder so that its amount reached 0.10 parts by mass relative to 100 parts by mass of the toner particles. Silica fine powder was mixed into the toner particles in the same manner as above so that its amount reached 0.20 parts by mass and 0.50 parts by mass, and these were used as samples for the calibration curve.

[0315] The pellets of each sample for the calibration curve were prepared in the same manner using a tablet forming press, and when PET was used as a spectroscopic crystal, the count rate (unit: cps) of Si-Kα rays observed at a diffraction angle (2θ) = 109.08° was measured. In this case, the acceleration voltage and current value of the X-ray generating device were set to 24 kV and 100 mA, respectively. A linear function calibration curve was obtained so that the vertical axis represented the count rate of the obtained X-rays and the horizontal axis represented the amount of SiO2 added in each sample for the calibration curve.

[0316] Next, the toner to be analyzed is formed into pellets as described above using a tablet forming press, and the count rate of Si-Kα rays is measured. In addition, the content of SiO2 in the toner is determined from the above calibration curve.

[0317] Method for measuring the degree of aggregation of toner

[0318] The degree of aggregation of the toner is measured in the following manner.

[0319] As a measuring device, a measuring device obtained by connecting a digital display vibration meter "DIGI-VIBRO MODEL 1332A" (manufactured by Showasokki Co., Ltd.) to the side part of the vibration table of "POWDER TESTER" (manufactured by Hosokawa Micron Corporation) was used. In addition, a sieve with a mesh size of 25 μm (635 mesh), a sieve with a mesh size of 38 μm (390 mesh), and a sieve with a mesh size of 75 μm (200 mesh) were arranged in an overlapping manner from the top. The measurement was performed in the following manner under an environment of 23°C and 60% RH.

[0320] (1) Pre-adjust the vibration amplitude of the vibration table so that the displacement value of the digital display vibration meter reaches 0.60 mm (peak to peak).

[0321] (2) 5 g of the toner left to stand for 24 hours under an environment of 23° C. and 60% RH is accurately weighed and lightly placed on a sieve having a mesh size of 150 μm at the uppermost stage.

[0322] (3) The sieves are vibrated for 15 seconds, the mass of the toner remaining on each sieve is measured, and the degree of aggregation is calculated based on the following equation.

[0323] Aggregation degree (%) = {(mass of sample on a sieve with a mesh size of 75 μm (g)) / 5 (g)}×100

[0324] + {(mass of the sample on the sieve with a mesh size of 38 μm (g)) / 5 (g)}×100×0.6

[0325] + {(mass of the sample on the sieve with a mesh size of 25 μm (g)) / 5 (g)}×100×0.2

[0326] Calculation of the average proportion As of the domain area of ​​the crystalline resin component in the surface layer region from the surface of the toner particle to a depth of 200 nm

[0327] The cross section of the toner particle is observed with a transmission electron microscope, the cross-sectional area As of the domain formed by the crystalline resin component is calculated, and the dispersion state of the crystalline resin component in the toner is evaluated based on the average value of 100 randomly selected toner particles.

[0328] Specifically, the toner is embedded in a visible light curable embedding resin (D-800, manufactured by Nisshin-EM), and cut to a thickness of 60nm with an ultrasonic ultrathin slicer (EM5, manufactured by Leica), and stained with Ru using a vacuum staining device (manufactured by Filgen, Inc.). Thereafter, a transmission electron microscope (H7500, manufactured by Hitachi, Ltd.) is used to observe the cross section at an accelerating voltage of 120kV. The cross section of 100 toner particles with a weight average particle size of ±2.0μm is selected and the image of the cross section is taken for observation. The image obtained is processed using image processing software (Photoshop (registered trademark) 5.0, manufactured by Adobe) to clearly distinguish the domain of the crystalline resin component and the region of the resin. Specifically, the domain of the crystalline resin component can be distinguished in the following manner. The captured TEM image is binarized by setting the threshold value of the brightness (hue: 255) to 160 using image processing software. Here, the crystalline resin component of the toner and the photocurable resin D800 are bright areas, and areas other than the crystalline resin component of the toner are dark areas. The outline of the toner can be distinguished by the lightness and darkness of the toner and the photocurable resin.

[0329] The cross section of the toner particle is masked except for the surface region from the surface (profile of the cross section) of the toner particle to a depth of 200nm. Specifically, a line is drawn from the center of gravity of the cross section of the toner particle to a point on the profile of the cross section of the toner particle. A position 200nm away from the profile in the direction of gravity is specified on the line. In addition, this operation is performed for one week on the profile of the cross section of the toner particle, and the surface region from the profile of the cross section of the toner particle to 200nm is clearly shown. The area percentage occupied by the domain of the crystalline resin component in the area of ​​the obtained surface region is calculated and defined as As.

[0330] Method for measuring the exposure rate Bs of toner particles

[0331] Hereinafter, the exposure rate Bs of the toner particles is measured by the following procedure.

[0332] Measurement of the major diameter of external additives

[0333] The reflected electron image and secondary electron image of the external additive on the toner particle surface were taken using a scanning electron microscope Gemini 560 (trade name, manufactured by Carl Zeiss AG) at an acceleration voltage of 0.7 kV and an observation magnification of 50000. Here, a field of view excluding the outline of the toner was selected using the secondary electron image and its image was taken.

[0334] The toner is fixed to a sample stage using a carbon ribbon or the like and observed as it is.

[0335] The major diameter of the external additive was measured by using the obtained reflected electron image, and an external additive having a major diameter of 5 nm or more was used as the external additive.

[0336] In addition, the same process as above can be performed on a toner containing a plurality of external additives on the surface of the toner particles. When the reflected electron image is observed with Gemini 560, the element of each fine particle can be determined by performing elemental analysis at an accelerating voltage of 10 kV using an energy dispersive X-ray spectroscopic detector. In the case where the accelerating voltage is high, when the toner is overcharged, the element of each fine particle can be determined by previously evaporating platinum on the toner surface and performing elemental analysis.

[0337] Furthermore, fine particles of the same kind may be selected based on the characteristics of the shape. The major diameters of various fine particles may be calculated by performing the above-mentioned measurement on fine particles of the same kind.

[0338] Method for measuring coverage of external additives and exposure of toner particles

[0339] The coverage of the external additive according to the present disclosure is measured by an observed image in which the major diameter of the external additive has been determined. The coverage is calculated from the observed image using the image processing software "ImageJ" in the following manner.

[0340] Select only particles derived from external additives on the software by particle analysis. Next, display the area of ​​the selection interface by performing measurement settings. Obtain the coverage (area %) of the external additive in the visual field by dividing this value by the area of ​​the entire visual field. Perform this measurement on 100 visual fields, and define the average value of the obtained values ​​as the coverage of the external additive. In addition, "100-(coverage of external additives)" is defined as the exposure rate (area %) of the toner particles.

[0341] Methods for measuring molecular weight

[0342] The molecular weight distribution of THF-soluble matter of the toner is measured according to gel permeation chromatography (GPC) in the following manner.

[0343] First, the toner was dissolved in tetrahydrofuran (THF) at room temperature for 24 hours. In addition, the obtained solution was filtered through a solvent-resistant membrane filter "MYSHORIDISC" (manufactured by Tosoh Corporation) with a pore size of 0.2 μm to obtain a sample solution. In addition, the sample solution was prepared so that the concentration of the component soluble in THF was about 0.8% by mass. The sample solution was used for measurement under the following conditions.

[0344] Apparatus: HLC8320 GPC (detector: RI) (manufactured by Tosoh Corporation)

[0345] Column: Two units of Shodex LF-404 (manufactured by Showa Denko KK)

[0346] Eluent: Tetrahydrofuran (THF)

[0347] Flow rate: 1.0ml / min

[0348] Column oven temperature: 40.0°C

[0349] Sample injection volume: 0.10ml

[0350] The molecular weight of the sample is calculated by using a molecular weight calibration curve prepared using a standard polystyrene resin (for example, trade name "EasiVial PS-H polystyrene", manufactured by Agilent Technologies Japan, Ltd.).

[0351] Acid value measurement

[0352] The acid value is the number of milligrams of potassium hydroxide required to neutralize the acid contained in 1 g of a sample.

[0353] The acid value of the resin is measured in accordance with JIS K 0070-1992, and specifically, the acid value is measured by the following procedure.

[0354] (1) Preparation of reagents

[0355] 1.0 g of phenolphthalein was dissolved in 90 ml of ethanol (95% by volume), and ion-exchanged water was added thereto to adjust the amount of the solution to 100 ml, thereby obtaining a phenolphthalein solution.

[0356] 7g special grade potassium hydroxide is dissolved in 5ml water, and ethanol (95 volume %) is added thereto so that the amount of solution is adjusted to 1L. Thus solution is poured into an alkali-resistant container to avoid contact with carbon dioxide etc., and the resulting solution is left standstill for 3 days and filtered, thus obtaining potassium hydroxide solution. The potassium hydroxide solution obtained is kept in an alkali-resistant container. The coefficient of potassium hydroxide solution is determined by placing 25ml 0.1mol / L hydrochloric acid in a conical flask, adding a few drops of phenolphthalein solution thereto, titrating with potassium hydroxide solution and calculating the amount of potassium hydroxide solution required for neutralization. Prepare the hydrochloric acid of 0.1mol / L and use according to JIS K8001-1998.

[0357] (2) Operation

[0358] (A) This test

[0359] The sample of 2.0g pulverized resin is accurately weighed in a 200ml conical flask, and a mixed solution of 100ml toluene and ethanol (2:1) is added thereto to be dissolved therein for 5 hours. Next, a few drops of phenolphthalein solution are added thereto as an indicator, and the solution is titrated using potassium hydroxide solution. In addition, the time point when the light red of the indicator lasts for about 30 seconds is defined as the endpoint of the titration.

[0360] (B) Blank test

[0361] Titration was performed in the same manner as in the above operation, except that no sample was used (ie, only a mixed solution of toluene / ethanol (2:1) was used).

[0362] (3) The acid value was calculated by substituting the obtained result into the following equation.

[0363] A=[(CB)×f×5.61] / S

[0364] Here, A represents the acid value (mgKOH / g), B represents the amount of potassium hydroxide solution added in the blank test (ml), C represents the amount of potassium hydroxide solution added in the present test (ml), f represents the coefficient of the potassium hydroxide solution, and S represents the sample (g).

[0365] Method for quantifying boron atoms contained in toner particles

[0366] The content of boron (B) atoms in the toner particles is quantified by an inductively coupled plasma atomic emission spectrometer (ICP-AES (manufactured by Seiko Instruments Inc.)). As a pretreatment, 100.0 mg of the toner particles are acid-decomposed by using 8.00 ml of 60% nitric acid (for atomic absorption spectrometry, manufactured by KANTO CHEMICAL CO., INC.).

[0367] Method for removing external additives from toner to obtain toner particles

[0368] 160g of sucrose (manufactured by Kishida Chemical Co., Ltd.) is added to 100ml of ion exchange water and dissolved in a hot water bath to prepare a thick sucrose solution. 31g of a thick sucrose solution and 6ml of Contaminon N (a 10% aqueous solution of a neutral detergent for cleaning precision measuring instruments with a pH of 7, formed by a nonionic surfactant, an anionic surfactant and an organic builder, manufactured by Wako Pure Chemical Industries, Ltd.) are poured into a centrifuge tube (volume of 50ml). 1.0g of toner is added thereto, and toner lumps are broken up with a spatula or the like. The centrifuge tube is shaken at 300spm (round trips per minute) for 20 minutes in a shaking table (AS-1N, sold by AS ONE CORPORATION).

[0369] After shaking the centrifuge tube, the solution was transferred to a glass tube (50 mL) for a swing rotor and separated at 3500 rpm for 30 minutes by means of a centrifuge (H-9R, manufactured by KOKUSAN Co., Ltd.).

[0370] The toner particles and the external additive are separated from each other by performing this operation. After visually confirming that the toner particles are sufficiently separated from the aqueous solution, the toner particles separated into the uppermost layer are collected by a spatula or the like. The collected toner particles are filtered through a vacuum filter and dried by a dryer for more than 1 hour, thereby obtaining a sample for measurement. This operation is performed multiple times to ensure the required amount.

[0371] Example

[0372] Hereinafter, the present disclosure will be described in more detail with reference to Examples and Comparative Examples. Unless it exceeds the gist of the present disclosure, the present disclosure is not limited to the following Examples. In the description of the following Examples, unless otherwise stated, "parts" are based on mass.

[0373] Synthesis of polyester resin 1

[0374] Bisphenol A-ethylene oxide 2 mole adduct: 48 mole parts

[0375] Bisphenol A-propylene oxide 2 mole adduct: 48 mole parts

[0376] Terephthalic acid: 65 mol parts

[0377] Dodecenylsuccinic acid: 30 mol parts

[0378] The above monomers were put into a flask equipped with a stirring device, a nitrogen introduction tube, a temperature sensor, and a distillation column and heated to 195° C. for 1 hour, and it was confirmed that the mixture in the reaction system was uniformly stirred.

[0379] To 100 parts of these monomers, 0.7 parts of tin distearate was added. While further generated water was distilled off, the temperature was raised from 195° C. to 240° C. over 5 hours, and a dehydration condensation reaction was further performed at 240° C. for 2 hours. Next, the temperature was lowered to 190° C., 5 parts by mole of trimellitic anhydride were gradually added thereto, and the reaction was continued at 190° C. for 1 hour.

[0380] As a result, a non-crystalline polyester resin 1 having a glass transition temperature of 55.2° C., an acid value of 14.3 mgKOH / g, a hydroxyl value of 24.1 mgKOH / g, a weight average molecular weight of 43600, and a number average molecular weight of 6200 was obtained.

[0381] Synthesis of polyester resin 2

[0382] Bisphenol A-ethylene oxide 2 mole adduct: 48 mole parts

[0383] Bisphenol A-propylene oxide 2 mole adduct: 48 mole parts

[0384] Terephthalic acid: 65 mol parts

[0385] Dodecenylsuccinic acid: 30 mol parts

[0386] The above monomers were put into a flask equipped with a stirring device, a nitrogen introduction tube, a temperature sensor, and a distillation column and heated to 195° C. for 1 hour, and it was confirmed that the mixture in the reaction system was uniformly stirred.

[0387] To 100 parts of these monomers, 0.7 parts of tin distearate was added. While further generated water was distilled off, the temperature was raised from 195° C. to 240° C. over 5 hours, and a dehydration condensation reaction was further performed at 240° C. for 2 hours. Next, the temperature was lowered to 190° C., 5 parts by mole of trimellitic anhydride were gradually added thereto, and the reaction was continued at 190° C. for 4 hours.

[0388] As a result, a non-crystalline polyester resin 2 having a glass transition temperature of 56.2° C., an acid value of 10.0 mgKOH / g, a hydroxyl value of 20.1 mgKOH / g, a weight average molecular weight of 74,800, and a number average molecular weight of 10,200 was obtained.

[0389] Synthesis of polyester resin 3

[0390] Bisphenol A-ethylene oxide 2 mole adduct: 48 mole parts

[0391] Bisphenol A-propylene oxide 2 mole adduct: 48 mole parts

[0392] Terephthalic acid: 65 mol parts

[0393] Dodecenylsuccinic acid: 30 mol parts

[0394] The above monomers were put into a flask equipped with a stirring device, a nitrogen introduction tube, a temperature sensor, and a distillation column and heated to 195° C. for 1 hour, and it was confirmed that the mixture in the reaction system was uniformly stirred.

[0395] To 100 parts of these monomers, 0.7 parts of tin distearate was added. While further generated water was distilled off, the temperature was raised from 195° C. to 240° C. over 5 hours, and a dehydration condensation reaction was further performed at 240° C. for 2 hours. Next, the temperature was lowered to 190° C., 5 parts by mole of trimellitic anhydride were gradually added thereto, and the reaction was continued at 190° C. for 6 hours.

[0396] As a result, a non-crystalline polyester resin 3 having a glass transition temperature of 57.2° C., an acid value of 9.0 mgKOH / g, a hydroxyl value of 18.1 mgKOH / g, a weight average molecular weight of 81,000, and a number average molecular weight of 13,200 was obtained.

[0397] Synthesis of polyester resin 4

[0398] Bisphenol A-ethylene oxide 2 mole adduct: 48 mole parts

[0399] Bisphenol A-propylene oxide 2 mole adduct: 48 mole parts

[0400] Terephthalic acid: 65 mol parts

[0401] Dodecenylsuccinic acid: 30 mol parts

[0402] The above monomers were put into a flask equipped with a stirring device, a nitrogen introduction tube, a temperature sensor, and a distillation column and heated to 195° C. for 1 hour, and it was confirmed that the mixture in the reaction system was uniformly stirred.

[0403] To 100 parts of these monomers, 0.7 parts of tin distearate was added. While further generated water was distilled off, the temperature was raised from 195° C. to 240° C. over 5 hours, and a dehydration condensation reaction was further performed at 240° C. for 2 hours. Next, the temperature was lowered to 190° C., 8 mol parts of trimellitic anhydride were gradually added thereto, and the reaction was continued at 190° C. for 1 hour.

[0404] As a result, a non-crystalline polyester resin 4 having a glass transition temperature of 58.5° C., an acid value of 30.0 mgKOH / g, a hydroxyl value of 18.1 mgKOH / g, a weight average molecular weight of 38,000, and a number average molecular weight of 9,200 was obtained.

[0405] Synthesis of polyester resin 5

[0406] Bisphenol A-ethylene oxide 2 mole adduct: 48 mole parts

[0407] Bisphenol A-propylene oxide 2 mole adduct: 48 mole parts

[0408] Terephthalic acid: 65 mol parts

[0409] Dodecenylsuccinic acid: 30 mol parts

[0410] The above monomers were put into a flask equipped with a stirring device, a nitrogen introduction tube, a temperature sensor, and a distillation column and heated to 195° C. for 1 hour, and it was confirmed that the mixture in the reaction system was uniformly stirred.

[0411] To 100 parts of these monomers, 0.7 parts of tin distearate was added. While further generated water was distilled off, the temperature was raised from 195° C. to 240° C. over 5 hours, and a dehydration condensation reaction was further performed at 240° C. for 2 hours. Next, the temperature was lowered to 190° C., 10 parts by mole of trimellitic anhydride was gradually added thereto, and the reaction was continued at 190° C. for 1 hour.

[0412] As a result, a non-crystalline polyester resin 5 having a glass transition temperature of 58.5° C., an acid value of 34.0 mgKOH / g, a hydroxyl value of 16.1 mgKOH / g, a weight average molecular weight of 36,000, and a number average molecular weight of 8,700 was obtained.

[0413] Synthesis of polyester resin 6

[0414] Bisphenol A-ethylene oxide 2 mole adduct: 9 mole parts

[0415] Bisphenol A-propylene oxide 2 mole adduct: 95 mole parts

[0416] Terephthalic acid: 50 mol parts

[0417] Fumaric acid: 30 mol parts

[0418] Dodecenylsuccinic acid: 25 mol parts

[0419] The above monomers were added to a flask equipped with a stirring device, a nitrogen inlet pipe, a temperature sensor and a distillation tower and heated to 195° C. for 1 hour, and it was confirmed that the mixture in the reaction system was uniformly stirred. For 100 parts of these monomers, 1.0 part of tin distearate was added thereto. While further generated water was distilled off, the temperature was raised from 195° C. to 250° C. over 5 hours, and a dehydration condensation reaction was further performed at 250° C. for 4 hours.

[0420] As a result, a non-crystalline polyester resin 6 having a glass transition temperature of 61.5° C., an acid value of 16.0 mgKOH / g, a hydroxyl value of 25.2 mgKOH / g, a weight average molecular weight of 25,200, and a number average molecular weight of 6,100 was obtained.

[0421] Synthesis of polyester resin 7

[0422] Bisphenol A-ethylene oxide 2 mole adduct: 9 mole parts

[0423] Bisphenol A-propylene oxide 2 mole adduct: 95 mole parts

[0424] Terephthalic acid: 50 mol parts

[0425] Fumaric acid: 30 mol parts

[0426] Dodecenylsuccinic acid: 25 mol parts

[0427] The above monomers were added to a flask equipped with a stirring device, a nitrogen inlet pipe, a temperature sensor and a distillation tower and heated to 195° C. for 1 hour, and it was confirmed that the mixture in the reaction system was uniformly stirred. 1.0 part of tin distearate was added thereto with respect to 100 parts of these monomers. While further generated water was distilled off, the temperature was raised from 195° C. to 250° C. over 5 hours, and a dehydration condensation reaction was further performed at 250° C. for 2 hours.

[0428] As a result, a non-crystalline polyester resin 7 having a glass transition temperature of 60.2° C., an acid value of 19.8 mgKOH / g, a hydroxyl value of 28.2 mgKOH / g, a weight average molecular weight of 11200, and a number average molecular weight of 4100 was obtained.

[0429] Preparation of resin particle dispersion 1

[0430] Polyester resin 1: 100 parts

[0431] Methyl ethyl ketone: 50 parts

[0432] Isopropyl alcohol: 20 parts

[0433] Methyl ethyl ketone and isopropanol are added to a container. Thereafter, polyester resin 1 is gradually added thereto, and the mixture is stirred so that it is completely dissolved, thereby obtaining a polyester resin 1 solution. The temperature of the container containing the polyester resin 1 solution is set to 65°C, and while stirring the mixture, a 10% ammonia aqueous solution is gradually added dropwise to the container so that the total amount of the solution reaches 5 parts, and 230 parts of ion exchange water are further gradually added dropwise thereto at a rate of 10 ml / min to cause phase inversion emulsification. In addition, desolventizing is performed under reduced pressure using an evaporator, thereby obtaining a resin particle dispersion 1 of polyester resin 1. The particle size of the resin particle dispersion 1 is measured using a particle size measuring device (LA-950, manufactured by Horiba, Ltd.), and the volume average particle size of the resin particle dispersion 1 is 135 nm. In addition, the solid content of the resin particles is adjusted to 20% with ion exchange water.

[0434] Preparation of resin particle dispersions 2 to 7

[0435] Resin particle dispersions 2 to 7 were obtained in the same manner as above, except that polyester resins 2 to 7 were used instead of polyester resin 1 in the preparation of resin particle dispersion 1. The obtained resin particle dispersions are listed in Table 1.

[0436] Table 1

[0437] Resin particle dispersion Polyester resin Number average particle size (nm) Resin particle dispersion 1 Polyester resin 1 135 Resin particle dispersion 2 Polyester resin 2 140 Resin particle dispersion 3 Polyester resin 3 145 Resin particle dispersion 4 Polyester resin 4 135 Resin particle dispersion 5 Polyester resin 5 130 Resin particle dispersion 6 Polyester resin 6 130 Resin particle dispersion 7 Polyester resin 7 135

[0438] Preparation of colorant particle dispersion

[0439] Copper phthalocyanine (pigment blue 15:3): 45 parts

[0440] Anionic surfactant NEOGEN RK (manufactured by DKS Co., Ltd.): 5 parts

[0441] Ion exchange water: 190 parts

[0442] An aqueous dispersion having a colorant fine particle concentration of 20% (colorant fine particle dispersion) is prepared by mixing the above components, dispersing the components for about 1 hour using a high-pressure impact disperser NANOMIZER (manufactured by YOSHIDA KIKAICO., LTD.), and dispersing the colorant.

[0443] Preparation of release agent particle dispersion 1

[0444] Release agent (HNP-51, manufactured by NIPPON SEIRO CO., LTD., melting point 78°C): 45 parts

[0445] Anionic surfactant NEOGEN RK (manufactured by DKS Co., Ltd.): 5 parts

[0446] Ion exchange water: 190 parts

[0447] The above components were put into a mixing container equipped with a stirring device, and the mixture was heated to 90° C., circulated through CLEARMIX W-MOTION (manufactured by M Technique Co., Ltd.), and subjected to dispersion treatment for 60 minutes. The dispersion treatment was performed under the following conditions.

[0448] Rotor outer diameter: 3cm

[0449] Gap: 0.3mm

[0450] Rotor speed: 19000r / min

[0451] Screen rotation speed: 19000r / min

[0452] After the dispersion treatment, the mixture was cooled to 40°C under cooling treatment conditions of a rotor rotation speed of 1000 r / min, a screen rotation speed of 0 r / min and a cooling rate of 10°C / min, thereby obtaining a release agent particle dispersion having a volume average particle size of 160 nm and a solid content of 20%.

[0453] Preparation of release agent particle dispersion 2

[0454] Release agent (behenyl behenate, melting point 74°C): 45 parts

[0455] Anionic surfactant NEOGEN RK (manufactured by DKS Co., Ltd.): 5 parts

[0456] Ion exchange water: 190 parts

[0457] The above components were put into a mixing container equipped with a stirring device, and the mixture was heated to 90° C., circulated through CLEARMIX W-MOTION (manufactured by M Technique Co., Ltd.), and subjected to dispersion treatment for 60 minutes. The dispersion treatment was performed under the following conditions.

[0458] Rotor outer diameter: 3cm

[0459] Gap: 0.3mm

[0460] Rotor speed: 19000r / min

[0461] Screen rotation speed: 19000r / min

[0462] After the dispersion treatment, the mixture was cooled to 40°C under cooling treatment conditions of a rotor rotation speed of 1000 r / min, a screen rotation speed of 0 r / min and a cooling rate of 10°C / min, thereby obtaining a release agent particle dispersion having a volume average particle size of 170 nm and a solid content of 20%.

[0463] Production of toner particles 1

[0464] Resin particle dispersion 1: 700 parts

[0465] Colorant particle dispersion 1: 80 parts

[0466] Release agent particle dispersion 1: 30 parts

[0467] Release agent particle dispersion 2: 90 parts

[0468] Ion exchange water: 1000 parts

[0469] First, each of the above materials was added to a round stainless steel flask and mixed in the core forming step. Next, the mixture was dispersed at 5000 r / min for 10 minutes using a homogenizer ULTRA-TURRAX T50 (manufactured by IKA). A 1.0% nitric acid aqueous solution was added thereto to adjust the pH to 3.0, and the mixed solution was heated to 45° C. while appropriately adjusting the rotation speed of the mixed solution stirred with a stirring blade in a heating water bath.

[0470] The volume average particle diameter of the formed aggregated particles was appropriately confirmed by using COULTER Multisizer III, and in the case where aggregated particles (cores) having a diameter of 5.0 μm were formed, each of the following materials was added thereto in the shell forming step and further stirred for 1 hour, thereby forming a shell.

[0471] Resin particle dispersion 1: 300 parts

[0472] Ion exchange water: 300 parts

[0473] 2.0 mass% borax aqueous solution: 50 parts

[0474] Borax: manufactured by Wako Pure Chemical Industries, Ltd., sodium tetraborate decahydrate

[0475] Thereafter, in the spheronization step, the pH of the mixture was adjusted to 9.0 by using a 5% sodium hydroxide aqueous solution, stirring was continued, and heating was performed to 90°C.

[0476] Thereafter, the average circularity of the formed aggregated particles is appropriately measured by a flow-type particle image analyzer "FPIA-3000" (manufactured by Sysmex Corporation).

[0477] The aggregated particles were heated (heating time: 3 hours) until their average circularity reached 0.970. Next, the particles were cooled to 25° C. in a cooling step by rapidly adding ice thereto so as to set the cooling rate to 10° C. / sec or more, thereby obtaining a toner particle dispersion liquid 1.

[0478] Production of Toner Particles 2 to 14

[0479] Toner particles 2 to 14 were obtained in the same manner as described above, except that the conditions were changed as listed in Table 2 in the production of Toner particle 1.

[0480] Table 2

[0481]

[0482] Silica fine particles

[0483] The following silica fine particles were prepared as an external additive to be externally added to the toner particles. Silica fine particles 1: RX50 (manufactured by NIPPON AEROSIL CO., LTD.) Silica fine particles 2: TGC191 (manufactured by Cabot Corporation)

[0484] Silica fine particles 3: RX200 (manufactured by NIPPON AEROSIL CO., LTD.) Production Example of Toner 1

[0485] Toner particles 1: 100.0 parts

[0486] Silica fine particles 1: 2.2 parts

[0487] Silicon dioxide fine particles 3: 1.0 parts

[0488] The above materials were mixed at 3000 rpm for 7.5 minutes using a Henschel mixer FM10C (manufactured by NIPPON COKE & ENGINEERING CO., LTD.), thereby obtaining Toner 1. External addition conditions for Toner 1 are listed in Table 3. In addition, results obtained by performing various analyses on Toner 1 are listed in Table 4-1 and Table 4-2.

[0489] Production Examples of Toners 2 to 22 and Comparative Toners 1 to 5

[0490] Toners 2 to 22 and Comparative Toners 1 to 5 were obtained in the same manner as above except that the conditions were changed as listed in Table 3 in Production Example of Toner 1. The results obtained by subjecting these toners to the above-mentioned various analyses are listed in Table 4-1 and Table 4-2.

[0491] Table 3

[0492]

[0493]

[0494] Table 4-1

[0495]

[0496]

[0497] Table 4-2

[0498]

[0499]

[0500] Example 1

[0501] Color Laser Jet Enterprise 6701dn (manufactured by HP) was prepared as an evaluation machine and modified so that its printing speed was changeable. In addition, a process cartridge of the present disclosure which can be mounted on the above evaluation machine and set to a peripheral speed ratio R of 1.2 (the moving direction of the surface of the developing roller is opposite to the moving direction of the surface of the toner supply roller) and filled with 200 g of toner 1 was prepared, and a durability test was conducted by continuously feeding (printing) 15,000 sheets of horizontal lines with an image ratio of 1% at a printing speed of 75 sheets / min in a high temperature and high humidity environment (temperature of 30°C and humidity of 80% RH), and evaluating the concentration, concentration stability and fogging. The evaluation results are listed in Table 5.

[0502] Concentration evaluation and concentration stability evaluation

[0503] The density evaluation and density stability evaluation were performed by outputting a solid black image after the durability test. For each of the upper transfer material and the lower transfer material in the solid black image, the average value of the solid black image density at three points in the left, central, and right parts of the print section was measured. In addition, the image density stability was evaluated based on the difference in the average value of the image density between the upper and lower parts. In addition, an A4-sized GF-C081 (manufactured by Canon Inc., 81.4 g / m 2) was used as a transfer material, and the density was measured by using X-rite exact advance (manufactured by X-rite, Inc.).

[0504] The evaluation criteria are as follows.

[0505] · Judgment criteria for concentration evaluation

[0506] In the case where the average values ​​of the image densities in the upper and lower portions of the printed portion of the transfer material are both 1.20 or more, the density is excellent.

[0507] In the case where the average values ​​of the image density in both the upper and lower portions of the printed portion of the transfer material are less than 1.20, the density is problematic.

[0508] · Criteria for concentration stability evaluation

[0509] In the case where the difference in the average value of the image density between the upper portion and the lower portion of the transfer material is less than 0.20, the density stability is excellent.

[0510] In the case where the difference in the average value of the image density between the upper and lower portions of the transfer material is 0.20 or more, the density stability is problematic.

[0511] Fogging evaluation

[0512] The fogging was measured by using REFLECTOMETER MODEL TC-6DS (manufactured by Tokyo Denshoku Co., Ltd.). A green filter was used as a filter. When a solid white image was output, a drum (electrostatic latent image bearing member) was pasted with a Mylar tape, and the fogging was calculated by subtracting the reflectivity of the Mylar tape attached to the paper from the Macbeth density of the Mylar tape directly attached to the paper, and evaluated according to the following criteria.

[0513] Fogging (%) = reflectivity of the tape directly attached to the paper (%) - reflectivity of the tape attached to the drum (%)

[0514] · Criteria for evaluating fogging

[0515] When the fogging (%) is less than 2.0%, the fogging is excellent.

[0516] When the fogging (%) is 2.0% or more, the fogging is problematic.

[0517] Examples 2 to 25 and Comparative Examples 1 to 7

[0518] Examples 2 to 25 and Comparative Examples 1 to 7 were performed in the same manner as in Example 1 except that the peripheral speed ratio R and the toner in the evaluation of Example 1 were changed as listed in Table 5. The evaluation conditions and the evaluation results are listed in Table 5.

[0519] Table 5

[0520]

[0521]

[0522] While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments.The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions.

Claims

1. A process cartridge, which can be mounted on an image forming device, the process cartridge comprising: Development room, Wherein, the developing chamber comprises a developing roller that develops the electrostatic latent image formed on the surface of the photosensitive drum using a toner to form a toner image, a toner supplying roller that supplies the toner to the developing roller, a toner regulating member that regulates a layer thickness of toner on the developing roller, and Toner, The surface of the developing roller contacts the surface of the toner supply roller, and the moving direction of the surface of the developing roller is opposite to the moving direction of the surface of the toner supply roller at a position where the surface of the developing roller contacts the surface of the toner supply roller, In a mounted state in which the process cartridge is mounted on the apparatus main body of the image forming apparatus, at a position where the surface of the developing roller contacts the surface of the toner supplying roller, the moving direction of the surface of the toner supplying roller includes an upward component, The developing roller and the toner supplying roller are formed so that the peripheral speed ratio R represented by the formula (E1) satisfies 1.1≤R≤2.5， R=V RS / V D (E1) In formula (E1), V RS represents the absolute value of the peripheral speed of the toner supply roller surface in m / s, and V D represents the absolute value of the peripheral speed of the developing roller surface in m / s, The toner comprises toner particles and silica fine particles, The toner particles contain a crystalline resin component, The content of the silica fine particles is 1.5 parts by mass or more and 5.0 parts by mass or less relative to 100 parts by mass of the toner particles, The toner has a degree of aggregation of 70.0% or more and 99.0% or less, and When a cross section of the toner particle is observed using a transmission electron microscope, when an average area ratio of the domains of the crystalline resin component in a surface layer region from the surface of the toner particle to a depth of 200 nm is defined as As, As is 1.0 area % or less.

2. The process cartridge according to claim 1, in, When the processing box is installed on the device body of the image forming device, on the plane perpendicular to the rotation axis of the colorant supply roller, the angle between the horizontal line H in the cross section of the processing box and the straight line A connecting the centers of the rotation axes of the colorant supply roller and the developing roller is in the range of 9.5° to 10.3°.

3. A process cartridge according to claim 1 or 2, in, When the average area ratio of the toner particle surface portions not covered with the silica fine particles in the toner is defined as an exposure rate Bs, the exposure rate Bs is 55.0 area % or more and 80.0 area % or less.

4. A process cartridge according to claim 1 or 2, in, The toner particles include a non-crystalline polyester, and The non-crystalline polyester has a weight average molecular weight of 25,000 or more and 75,000 or less.

5. A process cartridge according to claim 4, in, The acid value of the non-crystalline polyester is 10.0 mgKOH / g or more and 30.0 mgKOH / g or less.

6. A process cartridge according to claim 1 or 2, in, The toner particles contain boron, and The boron content is 0.1 mass ppm or more and 100.0 mass ppm or less.

7. A process cartridge according to claim 1 or 2, in, The process cartridge includes a toner containing unit for containing the toner, The developing chamber has a communication port communicating with the toner containing unit, The toner containing unit is arranged below the developing chamber in the vertical direction, and The process cartridge includes a toner conveying member that conveys the toner contained in the toner containing unit to the toner supplying roller through the communication port provided in the developing chamber.

8. A process cartridge according to claim 7, in, The toner conveying member is a member having elasticity and rotating to convey the toner, The toner conveying member is configured such that In a region A on the upstream side of the communication port in the rotation direction of the toner conveying member, the free end of the toner conveying member contacts the wall surface of the toner containing unit, and as the toner conveying member rotates, the toner conveying member deforms against the elasticity so that the free end side, rather than the rotation axis side, is on the upstream side in the rotation direction of the toner conveying member, and At a position B which is the downstream side of the region A in the rotation direction of the toner conveying member and which is the upstream side of the communication port in the rotation direction of the toner conveying member, the free end of the toner conveying member is released from contact with the wall surface of the toner containing unit, and the deformed toner conveying member is elastically restored, so that the conveyed toner flies toward the communication port. The position B is arranged below the lower end of the communication port, When viewed in the axial direction of the developing roller, the rotation center of the toner conveying member and the rotation center of the developing roller are located on the same side with respect to a vertical line passing through the position B, and A maximum value of a rotation radius of the toner conveying member is larger than a distance between a rotation center of the conveying member and a lower end of the communication port.

9. The process cartridge according to claim 1 or 2, further comprising: a driving force receiving unit provided at an end portion of a shaft of the toner supply roller; a first driving force transmitting unit for transmitting the driving force from the driving force receiving unit to the toner supplying roller; a second driving force transmission unit provided in the toner supply roller and configured to transmit the driving force received by the first driving force transmission unit to the developing roller; and A third driving force transmission unit is provided in the developing roller and is used to transmit the driving force from the second driving force transmission unit to the developing roller.

10. A process cartridge according to claim 9, in, With the radius of the developing roller defined as rD in mm and the radius of the toner supplying roller defined as rRS in mm, the second driving force transmission unit and the third driving force transmission unit are connected to be driven so that the rotational angular velocity ratio λ represented by the formula (E2) satisfies 1.1≤λ×rRS / rD≤2.5, λ=ωRS / ωD(E2) In formula (E2), ωRS represents the rotational angular velocity of the toner supply roller in rad / second, and ωD represents the rotational angular velocity of the developing roller in rad / second.

11. A process cartridge according to claim 1 or 2, in, The peripheral speed ratio R satisfies 1.2≤R≤1.5.

Images