JP2010282017A - Electrostatic charge image developing toner, method for manufacturing the same, developing method, developing device, image forming apparatus and method for evaluating electrostatic charge image developing toner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for evaluating an electrostatic charge image developing toner by which the fluidity and electrostatic chargeability of a toner can be properly evaluated. <P>SOLUTION: The surface shape of a toner particle is repeatedly photographed 5-30 times with an SEM; on the basis of the photographed images, the contour of the toner particle surface is divided by a square whose one side a corresponds to 1/6,000-1/20 of a particle diameter of the toner particle; the number N(a) of squares formed by the division is calculated; the relationship between N(a) and a satisfies expression (1): N(a)∝a<SP>-K</SP>; the relationship between an average value of K value obtained using expression (1) and toner charge quantity Q/d is established; and the surface shape of the toner particle is made optimum by evaluation by K value at which the Q/d becomes larger than a prescribed value, whereby it is made possible to obtain an electrostatic charge image developing toner giving high image quality with good dot reproducibility. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an electrostatic charge developing toner, a toner cartridge, a process cartridge, a method for producing an electrostatic charge developing toner, a developing method, a developing device, an image forming apparatus, and an electrostatic charge developing toner evaluation method.

  The image quality of copiers and printers has been improved, and recently, the reproducibility of fine dots has become very important. The dot reproducibility is greatly influenced by the charge amount of the toner and developer in addition to the fluidity of the toner and developer, and the toner layer or developer layer having a uniform and high development efficiency in the fine electrostatic latent image portion. It has become necessary to provide a stable supply. Furthermore, the speed of copying machines and printers has increased, and stable supply of toner and developer with high development efficiency to the development area has become more essential than ever.

  Further, as the image quality is improved, the toner used in the toner is becoming smaller in particle size and higher in function. Therefore, the structure of the toner has become complicated, and finer control at the time of toner production has become necessary than before. In particular, the chargeability and fluidity of toner affect the various image qualities in addition to the dot reproducibility, and are considered to be very important techniques.

  In addition, when the toner production method changes from the pulverization method to another method such as a polymerization method, the change in charging characteristics and flow characteristics with respect to the production conditions is large. Control and evaluation is required.

  For example, as a toner capable of forming a good image with good toner mobility in the development area and free from photoreceptor fogging and carrier adhesion, the average circularity> 0.96, the circularity standard deviation SD <0.04, and the toner It has been proposed to use a toner having a surface shape D / d50 ≧ 0.45 (see, for example, Patent Document 1). However, since the toner described in Patent Document 1 does not consider the chargeability of the toner, variations occur between the toners, and it is difficult to obtain high image quality with good dot reproducibility.

In addition, the present inventors previously have flow characteristics (fluidity) and charging characteristics that can cope with higher speeds of copying machines, printers, etc., and have good dot reproducibility and high quality images (high quality) even in repeated use. For the purpose of providing a toner for electrostatic charge development capable of obtaining an image quality stably, the particle surface shape of the toner containing the resin and the pigment is measured by SEM, and the outline of the toner particle surface is represented by the particle size of the toner particle. classified by one side of a square d becomes 1 / 6000-1 / 20, as an index the D value in formula N (d) .alpha.d ^-D that satisfied when the calculated number of square N (d) that can be at that time A method for evaluating an electrostatic charge developing toner has been proposed, characterized in that the electrostatic charge developing toner is evaluated. If the fluidity of the target toner is evaluated and managed by this evaluation method, it is possible to appropriately evaluate whether the toner has good dot reproducibility and a high-quality image (for example, patent document). 2).

  The present invention has been made in view of the above circumstances, and further improves the electrostatic charge developing toner described in Patent Document 2 and its evaluation method, so that the fluidity and chargeability of the toner are more appropriate. An object of the present invention is to provide an electrostatic charge developing toner capable of obtaining a high image quality with good dot reproducibility, and an electrostatic charge developing toner evaluation method capable of evaluating such a toner.

  Other objects include a toner cartridge containing the toner, a process cartridge, a method for producing a toner for developing electrostatic charge capable of stably providing the toner, a developing method using the toner, and a developing device. An image forming apparatus is also provided.

In order to solve the above-mentioned problem, the invention according to claim 1, the toner particles comprising at least a resin and a pigment are photographed with a scanning electron microscope, and the surface of the toner particles is based on a photographed image of the toner particles. Is divided into squares with a side of 1/600 to 1/20 of the particle size of the toner particles, and the number N (a) of the squares formed at that time is determined. N (a) and a The following relationship (1) is satisfied, and the average value of K values obtained by using the equation (1) and the toner charge amount Q / d (where d indicates the particle size of the toner): The electrostatic charge developing toner is characterized in that the relationship is determined and the value of K at which the Q / d is larger than a predetermined value is 1.031 to 1.040.
N (a) ∝a- ^K (1)

  According to a second aspect of the present invention, in the electrostatic charge developing toner according to the first aspect, the predetermined value of the toner charge amount Q / d is 0.5 (−fC / μm).

  Further, the invention of claim 3 is the electrostatic charge developing toner of claim 1 or 2, wherein when the interparticle force of the toner is measured by the AFM colloid probe method, the average value of the interparticle force of the toner is 1 nN to 30 nN.

  According to a fourth aspect of the present invention, in the electrostatic charge developing toner according to any one of the first to third aspects, the average circularity of the toner is 0.90 to 0.99.

  Further, the invention of claim 5 is the electrostatic charge developing toner according to any one of claims 1 to 4, wherein an additive composed of at least silicon dioxide having an average particle size of 10 nm to 200 nm is added to the surface of the toner. It is characterized by being adhered or fixed at a coverage of%.

  The invention according to claim 6 is the electrostatic charge developing toner according to any one of claims 1 to 5, wherein the additive adhered or fixed to the surface of the toner contains titanium dioxide having an average particle diameter of 10 nm to 200 nm. It is characterized by that.

  According to a seventh aspect of the present invention, in the electrostatic charge developing toner according to any one of the first to sixth aspects, the toner contains a charge control agent.

  An eighth aspect of the invention is the electrostatic charge developing toner according to any one of the first to seventh aspects, wherein the toner contains a release agent.

The invention of claim 9 is the electrostatic charge developing toner according to any one of claims 1 to 8, wherein at least one of the resins is a crystalline polyester represented by the following general formula (1). It is characterized by being.
^{[-O-CO-CR 1 =} CR 2 -CO-O- (CH 2) n-] m (1)
(In the formula, n and m are the number of repeating units, and R ¹ and R ² represent a hydrogen atom or a hydrocarbon group.)

  The invention according to claim 10 is the toner for electrostatic charge development according to any one of claims 1 to 9, wherein the interparticle force of the toner as measured by an atomic force microscope is 1 to 30 nN. Features.

  The invention according to claim 11 is the toner for electrostatic charge development according to any one of claims 1 to 10, wherein the toner is prepared by a polymerization method using a composition containing a monomer or a prepolymer and a pigment. It is characterized by being made.

  The invention of claim 12 is the electrostatic charge developing toner according to any one of claims 1 to 10, wherein the toner is kneaded with a composition containing a resin and a pigment, and then cooled and pulverized. It is manufactured.

  A thirteenth aspect of the invention is a developing method characterized in that contact or non-contact development is performed using the electrostatic charge developing toner according to any one of the first to twelfth aspects.

  A fourteenth aspect of the present invention is a two-component development method using a carrier having a particle diameter of 20 to 70 μm together with the electrostatic charge developing toner according to any one of the first to twelfth aspects. .

  According to a fifteenth aspect of the present invention, there is provided a toner cartridge containing the electrostatic charge developing toner according to any one of the first to twelfth aspects.

  A sixteenth aspect of the present invention is a process cartridge characterized by containing the electrostatic charge developing toner according to any one of the first to twelfth aspects.

  According to a seventeenth aspect of the invention, the electrostatic charge developing toner according to any one of the first to twelfth aspects is accommodated, and the toner is supplied to an electrostatic latent image formed on an image carrier. A developing device that forms an electrostatic latent image into a toner image.

  The invention according to claim 18 includes an image carrier and a developing device that supplies toner to the electrostatic latent image formed on the image carrier and converts the toner electrostatic latent image into a toner image. Further, in the image forming apparatus, the developing device is the developing device according to claim 17.

  According to the nineteenth aspect of the present invention, toner particles comprising at least a resin and a pigment are photographed with a scanning electron microscope, and the contour of the toner particle surface is defined based on the photographed image of the toner particles. The number N (a) of the squares formed at that time is determined by dividing the squares with a side of 1/6000 to 1/20 of the particle diameter, and the relationship between N (a) and a is the following (1) The relationship between the average value of K values obtained using the equation (1) and the toner charge amount Q / d (where d represents the particle size of the toner) is obtained, and the Q / d The toner evaluation method for electrostatic charge development is characterized in that the surface shape of the toner particles is evaluated based on a value of K that becomes greater than a predetermined value.

N (a) ∝a- ^K (1)

  According to a twentieth aspect of the present invention, in the toner evaluation method for electrostatic charge development according to the nineteenth aspect, the toner is determined by a value of K where the predetermined value of the toner charge amount Q / d is 0.5 (-fC / μm). It is characterized by evaluating the surface shape of the particles.

According to the present invention, toner particles composed of at least a resin and a pigment are photographed by a scanning electron microscope, and based on the photographed image of the toner particles, the contour line of the toner particle surface is determined by the particle size of the toner particles. The number of squares N (a) formed at that time is obtained by dividing the square by a square of 1/6000 to 1/20, and the relationship between N (a) and a satisfies the following formula (1). Then, the relationship between the average value of K values obtained using the equation (1) and the toner charge amount Q / d (where d is the toner particle size) is obtained, and the Q / d is a predetermined value. By increasing the value of K to be 1.031 to 1.040, it is possible to provide a toner for developing an electrostatic charge that has good fluidity and good dot reproducibility even after repeated use.
N (a) ∝a- ^K (1)

  Further, toner particles composed of at least a resin and a pigment are photographed with a scanning electron microscope, and based on a photographed image of the toner particles, the contour line of the toner particle surface is 1/6000 to the particle diameter of the toner particles. The number N (a) of the squares formed at that time is divided by the square of one side a that is 1/20, and the relationship between N (a) and a satisfies the above expression (1). ) And the toner charge amount Q / d (where d is the particle size of the toner), and the value of K at which the Q / d is greater than a predetermined value is obtained. By evaluating the surface shape of the toner particles based on the value, it is possible to provide an evaluation method for an electrostatic charge developing toner capable of appropriately evaluating the fluidity and chargeability of the toner.

  Further, according to the present invention, in the electrostatic charge developing toner according to claim 2 or 20, or the evaluation method thereof, the value of K is adjusted to be 1.031 to 1.040, and the toner charge is By using an electrostatic charge developing toner having an amount Q / d of 0.5 (−fC / μm), an electrostatic charge developing toner capable of obtaining a high image quality with good dot reproducibility, the toner is stabilized. It is possible to provide a method for producing a toner for developing an electrostatic charge that can be provided, a developing device using the toner, and an image forming apparatus.

It is a figure which shows the covering square process image based on the SEM image of the toner for electrostatic charge development in this invention. Relationship between the side a of the square and the number N (a) of squares in the coated square processed image of the toner for developing electrostatic charge evaluated by the method for evaluating the toner for developing electrostatic charge according to the present invention (loga-logN (d) characteristic) FIG. FIG. 6 is a graph showing a relationship between a K value and a toner charge amount (Q / d) in the present invention. It is a graph which shows the relationship between K value in this invention, and dot reproducibility evaluation. It is a schematic diagram showing a mixing step of a method for producing a toner for developing electrostatic charge according to an embodiment of the present invention. 1 is a diagram illustrating a schematic configuration of a developing device according to an embodiment of the present invention. 1 is a diagram illustrating a schematic configuration of an image forming apparatus according to an embodiment of the present invention.

  In the study of appropriately evaluating the fluidity and chargeability of the toner, the present inventors directly measured by changing the scale, which is a unit for measuring the contour of the surface shape of the toner, and changing it directly. The change in periodicity of fine irregularities on the particle surface was investigated. Furthermore, as a result of examining the relationship between the change in periodicity of fine irregularities on the toner particle surface and the charging of the toner, it was found that the change in periodicity of fine irregularities on the toner particle surface is very important for the chargeability. By evaluating it, it was found that toner chargeability in the development area can be improved appropriately, uniform and high development efficiency toner can be realized, and high image quality with excellent dot reproducibility can be obtained. .

That is, the particle surface shape of the toner composed of at least a resin and a pigment is repeatedly photographed 5 to 30 times with a scanning electron microscope (SEM), and based on the photographed image, the outline of the toner particle surface is plotted on the toner particle surface. The number N (a) of the squares formed at that time is determined by dividing the squares with a side of 1/6000 to 1/20 of the particle diameter, and the relationship between N (a) and a is the following (1) The relationship between the average value of 5 to 30 times of the K value obtained using the equation (1) and the toner charge amount Q / d (where d indicates the particle size of the toner) is obtained. It is possible to obtain an electrostatic charge developing toner with high dot reproducibility and high image quality by optimizing the surface shape of the toner particles by evaluating the value of K where the Q / d is larger than a predetermined value. It is what.
N (a) ∝a- ^K (1)

In the toner of the present invention, a toner particle contour image is taken with an SEM, the image is binarized, further line-drawn, and the toner particle contour image is analyzed to form an irregular shape on the toner particle surface. To evaluate. When this evaluation method is used, the resolution is very high, and a fine surface irregularity shape of one toner particle can be evaluated. In the present invention, the contour line of the toner particle surface is divided by a square of one side a, the number N (a) of the squares formed at that time is obtained, and the relationship between N (a) and a is expressed by the following equation (1). The fine surface shape of the toner particles was evaluated based on the value of K when satisfied.
N (a) ∝a- ^K (1)

  Whether or not the above formula (1) is satisfied was evaluated by obtaining a relational characteristic between a and N (a) by changing a. The value of a was set to be 1/6000 to 1/20 of the particle diameter of the toner particles in order to evaluate the fine uneven state on the toner particle surface. In order to investigate whether or not the above formula (1) is satisfied, the value of a is changed by 3 points or more (preferably 5 points or more) within the range of 1/6000 to 1/20 of the particle diameter of the toner particles. The relationship characteristics between a and N (a) were obtained. When the value of a is less than 1/6000 of the particle size of the toner particles, the measurement scale becomes very fine, and the influence of blurring of the contour line becomes large, making accurate evaluation impossible and not suitable for analysis. . Further, when the value of a is larger than 1/20 of the particle size of the toner particles, it is not suitable for analysis because the change in fine irregularities on the toner particle surface cannot be evaluated and an erroneous result is generated. . Further, since the basis of the analysis is the SEM image of the toner particles, it is necessary to take a clear contour image of the particles. For this reason, it is better to use a high-resolution SEM such as an FE-SEM for the SEM, and the image is focused on the outline of the toner particles.

The flow of measuring the shape of the toner particle surface in this evaluation method is shown below based on FIG.
(1) A contour image of toner particles is taken by SEM (see FIG. 1A).
(2) The contour image is binarized (see FIG. 1B).
(3) The binarized contour image obtained in (2) above is used as a contour image (see FIG. 1C).
(4) The contour line is divided into squares with one side a, and the number N (a) of the squares at that time is obtained (see FIG. 1D).
(5) The measurement of the above (4) is repeated by changing the scale a.
(6) A relational characteristic between a and N (a) is obtained.
(7) From the log-log plot of the data in (6) above, determine the value of K using the above equation (1).

  The operations (1) to (7) are repeated to evaluate the fine uneven shape on the toner particle surface. The method of evaluating the uneven shape of the toner is an example, and the number of squares was determined by dividing the square by a side a. For example, the contour line is divided by a predetermined length contour line using a compass. You may make it obtain | require the number divided by.

  An example of the result of the relational characteristic between a and N (a) measured by this evaluation method is shown in FIG. When the relationship characteristic between a and N (a) is represented by a log-log graph, it can be seen that there is a very clean linear relationship and a negative correlation of the primary line. From this, it can be seen that the relational characteristic between a and N (a) satisfies the equation (1), and the value of K can be obtained from the slope of the primary straight line 1 in FIG.

  Using the K value thus obtained, the relationship with the chargeability of the toner was examined. FIG. 3 shows the result. In FIG. 3, Ex1 to Ex11 and ratios 1 and 2 plot the K values and Q / d values of the toners obtained in Examples 1 to 11 and Comparative Examples 1 and 2, which will be described later. It is what. In this case, the chargeability (Q / d) of the toner was evaluated using an E-spart device (manufactured by Hosokawa Micron). In this measurement method, a developer in which toner and carrier (fixed of the same type) are mixed is placed in a cylindrical container (25 mmφ × 30 mm length) with the same toner concentration and stirred for 10 minutes (280 rpm). The toner was magnetically deposited on the disk of the E-spart device, air was blown into the developer to separate the toner from the carrier, and the charge amount of the toner was measured. As a result, as shown in FIG. 3, the toner charge amount Q / d increases as the value of K increases, reaches a maximum at about 1.035, and then decreases. Assuming that the toner charge amount is good when the toner charge amount Q / d is 0.5 (−fC / μm) or more, the toner charge amount is obtained when the K value is 1.031 to 1.040. It was found that the amount Q / d was 0.5 (−fC / μm) or more, and the toner charge amount was optimized. (The total number of particles measured with an E-spart apparatus was 3000.)

  In addition, one toner particle is attached to the tip of the probe or its periphery with an adhesive, and the probe is pressed once against the surface of the toner powder phase composed of the same toner particles by an atomic force microscope (AFM). The force acting between the toner particles at that time is measured, and the interparticle force between the toner particles is determined by the difference in force when the probe is brought close to and separated from the toner powder phase. evaluated. At that time, measurement was repeated 10 to 50 times, and the average value was evaluated. As a result, when the value of K was 1.031 to 1.040, the average value of the interparticle force was 1 nN to 30 nN, indicating a small value.

  From the results of the above toner charge amount and interparticle force, when the K value is smaller than 1.031, the contact area between the particles is large, so the interparticle force between the toner particles is large, and the fluidity between the toner particles is high. As a result, the friction efficiency decreased and the toner charge amount decreased. When the K value is larger than 1.040, the number of contact points due to the unevenness of the toner particle surface increases, the interparticle force increases, the fluidity between the toner particles deteriorates, the friction efficiency decreases, and the toner charge amount decreases. It was. It seems that irregularities with random periods are effective for fluidity, but it is very important to have regular protrusions that are regular to a certain extent, and it is regular that pollen is very fluid. This is thought to be due to unevenness. Thus, if there are regular and moderate convex portions, even if the particles are partially deformed or adsorbed substances are present on the particle surface, the influence on the ease of movement becomes small. In the present invention, fine regular irregularities were evaluated by repeatedly measuring while changing the measurement scale finely.

  The accuracy is higher than that of the conventional scanning probe microscope (SPM) analysis, and the evaluation corresponding to the characteristics such as the actual charging property and fluidity becomes possible. In the SPM method, the average particle diameter of the toner is as small as 4 μm to 8 μm, so that it is difficult to measure by bringing the probe close to or in contact with a part of the toner particle surface, and the evaluation area is smaller than 1000 nm × 1000 nm. Only partial evaluation of toner particles is possible. In addition, it is necessary to correct the curvature of the toner particle surface. Toner having good chargeability can be made by surface-treating the surface of the toner particles with fine particles to form a structure having irregularities with a certain regular period.

  However, it is difficult if the surface of the toner (base material) before adding the fine particles is a rough surface with severe irregularities, and the average circularity needs to be 0.9 to 0.99. If the average circularity is less than 0.9, it is difficult to control the surface irregularity shape even if fine particles are added, and it is difficult to obtain the optimum K value. This causes problems such as scattering other than the chargeability of the toner and poor cleaning properties. The circularity of this toner was measured using a flow type particle image analyzer (FPIA-2000; manufactured by Sysmex Corporation). As a method for controlling the shape of the toner particles, the toner particles after the classification process are put into a rotating body and rotated at a high speed (hybridizer, manufactured by Nara Machinery Co., Ltd.), or heat is instantaneously applied to the particle surface. It can be realized by passing through a simple process (Sufusion System, Nippon Pneumatic Industry Co., Ltd.).

  The fine uneven shape on the surface of the toner particles can be controlled by the kind of fine particles of the additive, the particle diameter, the mixing conditions at the time of addition and the fixing injection conditions. The fine particles to be added are optimally inorganic fine powder, and the average particle size is optimally a small particle size of 10 nm to 200 nm. In the case of additive fine particles having a particle size of less than 10 nm, it is difficult to produce the effect of unevenness, and in the case of a particle size of more than 200 nm, it is difficult to create appropriate unevenness. In this case, in addition to using only one kind of fine particles having a small particle diameter of 10 nm to 200 nm, at least two kinds of inorganic fine powder having an average particle diameter of 10 nm to 100 nm and inorganic fine powder having an average particle diameter of 100 to 200 nm are used in combination. Alternatively, it may be adhered or fixed to the surface of the toner made of resin or pigment.

  In the present invention, it is necessary to put the value of K on the surface of the toner particles in the condition range of 1.031 to 1.040, and the conditions for realizing it were examined. As a result, it was found that this can be realized when an additive comprising at least silicon dioxide (silica) having an average particle diameter of 10 to 200 nm is adhered or fixed to the surface of the toner at a coverage of 20 to 30%. The additive coverage on the toner particle surface was determined from the area occupied by the additive on the toner particle surface from the SEM image of the toner particle. In that case, silicon dioxide having an average particle diameter of 10 to 100 nm and silicon dioxide having an average particle diameter of 100 to 200 nm may be added in combination, or titanium dioxide having an average particle diameter of 10 to 200 nm may be included. Further, the following inorganic fine powder may be used.

  Inorganic fine powders as additive fine particles used in the present invention include Si, Ti, Al, Mg, Ca, Sr, Ba, In, Ga, Ni, Mn, W, Fe, Co, Zn, Cr, and Mo. , Cu, Ag, V, Zr, and other oxides and composite oxides. Of these, fine particles of silicon dioxide (silica), titanium dioxide (titania), and alumina are preferably used. Furthermore, it is effective to subject these fine particles to surface modification treatment with a hydrophobizing agent or the like. Typical examples of the hydrophobizing agent include the following.

  Dimethyldichlorosilane, trimethylchlorosilane, methyltrichlorosilane, allyldimethyldichlorosilane, allylphenyldichlorosilane, benzyldimethylchlorosilane, bromomethyldimethylchlorosilane, α-chloroethyltrichlorosilane, p-chloroethyltrichlorosilane, Examples include chloromethyldimethylchlorosilane, chloromethyltrichlorosilane, hexaphenyldisilazane, hexatolyldisilazane, and the like.

  The coverage of the inorganic fine powder on the surface of the toner particles is preferably 20 to 30% with respect to the toner surface. If it is less than 20%, the value of K on the surface of the toner particles becomes smaller than 1.031, and the effect of improving the toner fluidity becomes poor. On the other hand, if it exceeds 30%, the value of K on the surface of the toner particles becomes larger than 1.040, the toner fluidity is deteriorated, the toner scatters between fine lines of the image, the inside of the machine, the scratches and abrasion of the photoreceptor, etc. Problems tend to occur.

  Further, a fine particle charge control agent may be adhered or fixed to the surface of the toner composed of at least a resin or a pigment so that the toner surface has an appropriate unevenness. The average particle size is optimally as small as 10 nm to 200 nm. When the particle diameter is smaller than 10 nm, it is difficult to produce the unevenness effect, and when the particle diameter is larger than 200 nm, it is difficult to create appropriate unevenness. Examples of charge control agents include nigrosine and quaternary ammonium salts, triphenylmethane dyes, imidazole metal complexes and salts, salicylic acid metal complexes and salts, organoboron salts, calixarene compounds, etc. Also good.

  As the mixing or fixing injection conditions at the time of addition, the shape of the toner particle surface is controlled mainly by the mixing rotation speed during the mixing process of the toner and fine particles. That is, the mixing rotation speed can control the force for attaching the fine particles to the toner surface. The mixing rotation speed is optimally 1000 rpm to 6000 rpm. When the mixing rotation speed is lower than 1000 rpm, the fine powder adheres to the toner (base material) surface with a very weak force. Stability is lost, and toner scattering, internal contamination, etc. are likely to occur. When the mixing rotation speed is higher than 6000 rpm, the added fine powder is eaten into the surface of the toner (base material) before being added, and the surface unevenness is leveled to reduce the unevenness, and the fluidity is reversed. Deteriorate.

  These mixing conditions vary depending on the type of mixer. In the mixer, powder is mixed by rotating the container, etc., mixed by stirring blades, kneaded through a gap, etc., rotated at high speed to collide with the wall, charged into high-speed air current and collided with particles, etc. However, in the present invention, the fine particles adhering to the toner surface are finely dispersed and uniformly adhered to each other by passing through a gap between the walls to give shear energy between the particles, or by using a stirring blade. A method of giving collision energy to particles by rotating at high speed or throwing it into a high-speed air stream is suitable. In the case of such a mixer, since the shear energy acting on the particles and the collision energy between the particles are large, the energy acting between the toner (base material) and the fine particles before being added tends to be large. It is necessary to finely adjust the optimum conditions. That is, it is necessary to carry out the mixing under the optimum mixing condition of 1000 rpm to 6000 rpm. The mixing time is preferably short so that the temperature of the toner does not increase.

  The toner having this structure has a weight average particle diameter of preferably 4 μm to 8 μm, more preferably 5 μm to 7 μm, in order to realize a high quality image. If the weight average particle size is less than 4 μm, problems such as contamination inside the machine due to toner scattering during long-term use, image density reduction in a low-humidity environment, poor photoconductor cleaning, and the like are likely to occur, and there are concerns about the effects on the human body. Further, when the weight average particle diameter exceeds 8 μm, the resolution of minute spots of 100 μm or less is not sufficient, and the image quality tends to be inferior due to many scattering to non-image areas.

  When a two-component developer is used as a developer using this toner, the average particle size of the carrier is required to be 20 μm to 70 μm in order to realize a high quality image. When the average particle diameter of the carrier is in the range of 20 μm to 70 μm, the charge amount of the toner can be made more uniform when the toner concentration in the developing device is in the range of 2 to 10% by weight. If it is smaller than 20 μm, carrier particles are likely to adhere to the photosensitive member as an image carrier, and the stirring efficiency with the toner becomes poor, and it becomes difficult to obtain a uniform charge amount of the toner. On the other hand, when the average particle diameter of the carrier exceeds 70 μm, fine image reproducibility deteriorates and high image quality is difficult to obtain.

  FIG. 4 shows the result of examining the relationship between the above-described K value and dot reproducibility. The dot reproducibility was evaluated in five levels (rank 1: bad → rank 5: good) as the roughness of an image formed by an image forming apparatus described later. The K value was determined as an average of values measured repeatedly 10 times. In FIG. 4, Ex1 to Ex11 and ratios 1 to 3 are plots of the dot reproducibility and K value of the toners obtained in Examples 1 to 11 and Comparative Examples 1 to 3 described later. . From the results shown in FIG. 4, the dot reproducibility evaluation is less than rank 4 and the dot reproducibility is not good in the comparative examples having K values outside the range of 1.031 to 1.040. However, it is clear that the dot reproducibility evaluation of Rank 4 or higher shows good dot reproducibility in the examples in which the K value is in the range of 1.031 to 1.040.

  Next, details of the toner and developer according to the present invention are shown below.

  Component resins constituting the toner according to the present invention include polystyrene resin, epoxy resin, polyester resin, polyamide resin, styrene acrylic resin, styrene methacrylate resin, polyurethane resin, vinyl resin, polyolefin resin, styrene butadiene resin, phenol resin, polyethylene resin. , Silicon resin, butyral resin, terpene resin, polyol resin and the like.

  Examples of vinyl resins include styrene such as polystyrene, poly-p-chlorostyrene, and polyvinyl toluene, and homopolymers of substituted styrene, styrene-p-chlorostyrene copolymer, styrene-propylene copolymer, and styrene-vinyltoluene. Copolymer, Styrene-vinylnaphthalene copolymer, Styrene-methyl acrylate copolymer, Styrene-ethyl acrylate copolymer, Styrene-butyl acrylate copolymer, Styrene-octyl acrylate copolymer, Styrene- Methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate copolymer, styrene-α-chloromethyl methacrylate copolymer, styrene-acrylonitrile copolymer, styrene-vinyl methyl ether copolymer Polymer, styrene-vinyl ethyl ester Ter copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-acrylonitrile-indene copolymer, styrene-maleic acid copolymer, styrene-maleic acid ester Examples thereof include styrene copolymers such as copolymers, polymethyl methacrylate, polybutyl methacrylate, polyvinyl chloride, and polyvinyl acetate.

  The polyester resin is composed of a dihydric alcohol as shown in the following group A and a dibasic acid salt as shown in the group B, and further a trihydric or higher alcohol as shown in the group C. Alternatively, carboxylic acid may be added as a third component.

  Group A: ethylene glycol, triethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4 butanediol, neopentyl glycol, 1,4 butenediol, 1,4-bis (hydroxymethyl) cyclohexane Bisphenol A, hydrogenated bisphenol A, polyoxyethylenated bisphenol A, polyoxypropylene (2,2) -2,2′-bis (4-hydroxyphenyl) propane, polyoxypropylene (3,3) -2, 2-bis (4-hydroxyphenyl) propane, polyoxyethylene (2,0) -2,2-bis (4-hydroxyphenyl) propane, polyoxypropylene (2,0) -2,2′-bis (4 -Hydroxyphenyl) propane and the like.

  Group B: maleic acid, fumaric acid, mesaconic acid, citraconic acid, itaconic acid, glutaconic acid, phthalic acid, isophthalic acid, terephthalic acid, cyclohexanedicarboxylic acid, succinic acid, adipic acid, sebacic acid, malonic acid, linolenic acid, or These acid anhydrides or esters of lower alcohols.

  Group C: Trivalent or higher alcohols such as glycerin, trimethylolpropane and pentaerythritol, and trivalent or higher carboxylic acids such as trimellitic acid and pyromellitic acid.

  As the polyol resin, an alkylene oxide adduct of an epoxy resin and a dihydric phenol, or a compound having one active hydrogen in the molecule that reacts with the glycidyl ether and the epoxy group, and an active hydrogen that reacts with the epoxy resin in the molecule. There are those obtained by reacting two or more compounds.

  Further, crystalline polyester may be used as the component resin constituting the toner. It is an aliphatic polyester having crystallinity, having a sharp molecular weight distribution, and increasing the absolute amount of its low molecular weight as much as possible. This resin undergoes a crystal transition at the glass transition temperature (Tg), and at the same time, the melt viscosity is suddenly lowered from the solid state and exhibits a fixing function to paper. By using this crystalline polyester resin, low-temperature fixing can be achieved without excessively reducing the Tg and molecular weight of the resin. Therefore, there is no decrease in storage stability associated with a decrease in Tg. Further, there is no excessively high gloss and offset resistance deterioration due to the low molecular weight. Therefore, the introduction of the crystalline polyester resin is very effective for improving the low-temperature fixability of the toner.

  In the toner of the present invention, the content of the crystalline polyester is 1 to 50 with respect to the total amount of the resin and the release agent in the toner in order to exhibit low-temperature fixability and ensure hot offset resistance. The content of the release agent is preferably 2 to 15% by weight. When the content of the crystalline polyester is less than 1% by weight, there is no effect on the low-temperature fixability, and when it exceeds 50% by weight, the hot offset property is deteriorated. When the release agent content is less than 2% by weight, the offset resistance may not be effective, and when it exceeds 15% by weight, the toner fluidity decreases.

The molecular structure of the crystalline polyester resin is not limited, but from the viewpoint of the crystallinity and softening point of the polyester resin, a diol compound having 2 to 6 carbon atoms, particularly 1,4-butanediol and 1,6-hexanediol. And an aliphatic polyester represented by the following general formula (1) synthesized using an alcohol component containing these derivatives and maleic acid, fumaric acid, succinic acid, and an acid component containing these derivatives It is preferable to contain.
^{[-O-CO-CR 1 =} CR 2 -CO-O- (CH 2) n-] m (1)
(Here, n and m are the number of repeating units. R ¹ and R ² are hydrocarbon groups.)

  From the viewpoint of the crystallinity and softening point of the polyester resin, a trihydric or higher polyhydric alcohol such as glycerin is added to the alcohol component to synthesize a non-linear polyester, and trimellitic anhydride or the like is added to the acid component. Polycondensation may be performed by adding a trivalent or higher polyvalent carboxylic acid.

  The glass transition temperature (Tg) of the crystalline polyester resin is desirably low so long as the heat resistant storage stability does not deteriorate, and is preferably in the range of 80 to 130 ° C. When the glass transition temperature (Tg) is less than 80 ° C., the heat-resistant storage stability deteriorates, and blocking tends to occur at the temperature inside the developing device. Cannot be obtained. The glass transition temperature (Tg) of the crystalline polyester resin is an endothermic peak temperature at the time of 2nd temperature increase by differential scanning calorimetry (DSC).

The following are used as the pigment used in the present invention.
Examples of black pigments include azine dyes such as carbon black, oil furnace black, channel black, lamp black, acetylene black, and aniline black, metal salt azo dyes, metal oxides, and composite metal oxides.

  Examples of yellow pigments include cadmium yellow, mineral fast yellow, nickel titanium yellow, navel yellow, naphthol yellow S, hansa yellow G, hansa yellow 10G, benzidine yellow GR, quinoline yellow lake, permanent yellow NCG, and tartrazine lake. .

  Examples of the orange pigment include molybdenum orange, permanent orange GTR, pyrazolone orange, Vulcan orange, indanthrene brilliant orange RK, benzidine orange G, and indanthrene brilliant orange GK.

  Examples of red pigments include Bengala, Cadmium Red, Permanent Red 4R, Resol Red, Pyrazolone Red, Watching Red Calcium Salt, Lake Red D, Brilliant Carmine 6B, Eosin Lake, Rhodamine Lake B, Alizarin Lake, Brilliant Carmine 3B.

  Examples of purple pigments include fast violet B and methyl violet lake. Examples of blue pigments include cobalt blue, alkali blue, Victoria blue lake, phthalocyanine blue, metal-free phthalocyanine blue, phthalocyanine blue partially chlorinated, fast sky blue, and indanthrene blue BC. Examples of green pigments include chrome green, chromium oxide, pigment green B, and malachite green lake. These can use 1 type (s) or 2 or more types.

  In particular, in color toners, it is essential to uniformly disperse a good pigment. Instead of putting the pigment directly into a large amount of resin, a master batch in which the pigment is once dispersed at a high concentration is prepared and diluted. The method of throwing in the form is used. In this case, a solvent is generally used to assist dispersibility. However, there is a problem of environment and the like, and in the present invention, water is used for dispersion. When water is used, temperature control is important so that residual moisture in the masterbatch does not become a problem.

  In the toner of the present invention, a charge control agent can be blended (internally added) inside the toner particles. However, it may be used by mixing (external addition) with toner particles. The charge control agent makes it possible to control the optimum charge amount according to the development system. In particular, in the present invention, the balance between the particle size distribution and the charge amount can be further stabilized. For controlling the toner to be positively charged, nigrosine and quaternary ammonium salts, triphenylmethane dyes, imidazole metal complexes and salts can be used alone or in combination of two or more. Further, as a toner for controlling the toner to be negatively charged, salicylic acid metal complexes, salts, organic boron salts, calixarene compounds, and the like are used.

  Further, a release agent can be internally added to the toner in the present invention to prevent offset at the time of fixing. Release agents include natural waxes such as candelilla wax, carnauba wax and rice wax, montan wax and derivatives thereof, paraffin wax and derivatives thereof, polyolefin wax and derivatives thereof, sazol wax, low molecular weight polyethylene, and low molecular weight polypropylene. And alkyl phosphate esters. The melting point of these release agents is preferably 65 to 90 ° C. When the temperature is lower than this range, blocking during storage of the toner tends to occur, and when the temperature is higher than this range, an offset is likely to occur in a region where the fixing roller temperature is low.

  A dispersant may be added for the purpose of improving the dispersibility of a release agent or the like. As the dispersant, styrene acrylic resin, polyethylene resin, polystyrene resin, epoxy resin, polyester resin, polyamide resin, styrene methacrylate resin, polyurethane resin, vinyl resin, polyolefin resin, styrene butadiene resin, phenol resin, butyral resin, terpene resin, There is a polyol resin or the like, and a mixture of two or more of these resins may be used. The addition amount of the dispersant is suitably 10 parts by weight or less with respect to 100 parts by weight of the resin. Even if it exceeds 10 parts by weight, the effect of acidity of the release agent is not seen, and conversely, the fixing property and the image reproducibility are deteriorated.

  Examples of the method for producing the toner according to the present invention include a pulverization method and a polymerization method (suspension polymerization, emulsion polymerization dispersion polymerization, emulsion aggregation, emulsion association, etc.), but are not limited to these production methods.

  As an example of the pulverization method, first, the above-mentioned resin, pigment or dye as a colorant, charge control agent, release agent, other additives, etc. are sufficiently mixed by a mixer such as a Henschel mixer, and then batch type. The constituent materials are well kneaded using a two-roll, Banbury mixer, continuous twin-screw extruder, continuous single-screw kneader, or the like, and cut after rolling and cooling. The toner kneaded product after cutting is crushed, coarsely pulverized using a hammer mill, etc., and further pulverized by a fine pulverizer or mechanical pulverizer using a jet stream, and a classifier or Coanda effect using a swirling airflow Is classified to a predetermined particle size by a classifier using Thereafter, an additive composed of inorganic fine particles or the like is adhered or fixed to the particle surface by a mixer under the optimum mixing conditions. After this mixing step, the surface shape of the toner particles is evaluated using this evaluation method in order to evaluate whether or not a predetermined particle structure is obtained. As a result of the evaluation, when the numerical value is within a predetermined setting range, it is turned to the wind sieving step, passed through a sieve of 250 mesh or more, and after removing coarse particles and aggregated particles, the sample is turned to the filling step, The toner of the present invention is obtained.

  As a method for producing the toner according to the present invention, methods other than the pulverization method are conceivable. As an example of the polymerization method, a monomer composition in which a colorant, a charge control agent and the like are added to a monomer is suspended in an aqueous medium. Toner particles are obtained by turbidity and polymerization. The granulation method is not particularly limited. For example, in the toner of the present invention, an oily dispersion in which at least a polyester-based prepolymer containing an isocyanate group is dissolved in an organic solvent, a pigment-based colorant is dispersed, and a release agent is dissolved or dispersed in an aqueous medium. A urea-modified polyester resin having a urea group by dispersing in the presence of inorganic fine particles and / or fine polymer particles and reacting the prepolymer with a polyamine and / or a monoamine having an active hydrogen-containing group in the dispersion. And a liquid medium contained in the dispersion containing the urea-modified polyester resin is removed.

  In the urea-modified polyester resin, the Tg is 40 to 65 ° C, preferably 45 to 60 ° C. The number average molecular weight Mn is 2500 to 50000, preferably 2500 to 30000. The weight average molecular weight Mw is 10,000 to 500,000, preferably 30,000 to 100,000. This toner contains, as a binder resin, a urea-modified polyester resin having a urea bond that has been increased in molecular weight by the reaction between the prepolymer and the amine. The colorant is highly dispersed in the binder resin.

  The obtained toner powder after drying is air-classified, and an additive composed of inorganic fine particles or the like is adhered or fixed to the particle surface by a mixer under the optimum mixing conditions. Alternatively, the charge control agent may be applied to the surface of the toner powder after drying and fixedly injected. Further, thereafter, an additive made from inorganic fine particles or the like may be adhered or fixed to the particle surface. By placing the charge control agent on the surface, the charge amount of the toner can be easily controlled.

  Specific means for mixing and fixing and injecting are as follows: a method of applying an impact force to the powder mixture with blades rotating at high speed; For example, there is a method of causing the particles to collide with an appropriate collision plate. As equipment, Ong mill (manufactured by Hosokawa Micron Co., Ltd.), I-type mill (manufactured by Nippon Pneumatic Co., Ltd.) has been modified to reduce the pulverization air pressure, hybridization system (manufactured by Nara Machinery Co., Ltd.), kryptron System (manufactured by Kawasaki Heavy Industries, Ltd.), automatic mortar, etc.

  In this mixing step, as shown in FIG. 5, the toner is supplied from the toner supply port 4 and the additive is supplied from the additive supply port 5 to the mixer 3, and after mixing, a predetermined mixing process is performed. The mixture thus mixed is discharged from the discharge port 7 and supplied to the next step. In this case, it is determined whether the particle structure of the mixture has a predetermined shape, and the valve 8 is opened and closed from the outlet 6 to separate the mixture into the container 9. Then, the surface shape of the toner particles of the mixture separated in the container 9 is evaluated using the evaluation device 2. As shown in FIG. 5, the evaluation device 2 includes an SEM device 2a and a device (personal computer) 2b for analyzing the value of K. As shown in FIG. 1, after the toner particle contour image is taken by the SEM apparatus, this image information is input to the K value analysis apparatus 2b, and the K value is calculated using the analysis software. As a result of the evaluation, when the numerical value is within a predetermined setting range, the mixture is supplied to the next step of the wind sieving step, passed through a sieve of 250 mesh or more, and after removing coarse particles and agglomerated particles, The sample can be sent to the filling step to produce an electrostatic charge developing toner.

  As described above, the relationship between the average value of 5 to 30 times of the K value obtained using the above equation (1) and the toner charge amount Q / d (where d indicates the particle diameter of the toner) is obtained. By evaluating the value of K where the Q / d is larger than a predetermined value and optimizing the surface shape of the toner particles, it is possible to stably and reliably obtain an electrostatic charge developing toner with high dot reproducibility and high image quality. It can be manufactured. The toner evaluation method for electrostatic charge development was performed in the toner and additive mixing step, but during the toner manufacturing process, the inspection after the charge control agent treatment, the inspection after the additive mixing step, and the mixing step It can be applied to the inspection after the wind sieving process, the inspection before filling, etc.

  Further, when used as a two-component developer, a two-component developer is obtained by mixing with a magnetic carrier described later at a predetermined mixing ratio.

  This toner can be used as a one-component developer used in a contact or non-contact development system. As the contact or non-contact development method, various known methods are used. For example, a contact development method using an aluminum sleeve, a contact development method using a conductive rubber belt, and a non-contact development method using a development sleeve in which a conductive resin layer containing carbon black or the like is formed on the surface of an aluminum base tube. . This toner is excellent in fluidity when developed using an AC bias voltage component during development, so that the toner vibrates faithfully according to the electric field, and can faithfully develop fine electrostatic latent images, thereby reproducing dots. Development with good characteristics becomes possible.

  For example, in the one-component development method, as shown in FIG. 6, a roller-shaped doctor roller 13 for supplying a toner layer uniformly at the outlet of the developing roller 12 serving as a toner supply unit in a case 18 containing toner or a supply. The toner of the present invention can be used in the developing device 11 provided with the roller 14. In FIG. 6, reference numeral 10 denotes a drum-shaped photoconductor as an image carrier, reference numeral 15 denotes a stirring roller for stirring the toner, and reference numeral 17 denotes a replenishing toner supplied from the toner replenishing hopper 16 to the stirring roller 15 as appropriate. A toner replenishing roller to be supplied. In such a system, the chargeability of the toner greatly affects the uniformity of the toner layer on the developing roller 12 and the durability characteristics. When the durability characteristics are poor, not only filming on the photosensitive member 10 but also filming on the doctor roller 13 and the supply roller 14 occurs. For this reason, the toner layer cannot be formed uniformly, the toner charge becomes non-uniform, and the toner charge amount becomes small. For this reason, poor development occurs.

  However, when the toner of the present invention is used, the toner is excellent in chargeability, so that a uniform thinning of the toner layer on the developing roller 12 via the supply roller 14 and the doctor roller 13 can be easily realized. The toner can be stably conveyed onto the developing roller 12 at all times. Further, filming on the doctor roller 13 and the supply roller 14 does not occur, stable development is performed, and the system has excellent durability characteristics.

  In addition, since the toner of the present invention is excellent in fluidity in addition to chargeability, it can be sufficiently stored in a cartridge container, and is configured to convey toner from the cartridge container to the developing device 11. Also suitable for. The cartridge container includes a toner cartridge that fills toner, at least the photoconductor 10 and the developing device 11, and can be used as a process cartridge that fills the toner storage portion of the developing device 11. Usually, these toner cartridges or process cartridges are mounted on an image forming apparatus to form an image.

  Further, when the magnetic toner is used, magnetic particles may be internally added to the toner particles. Examples of the magnetic material include ferromagnetic materials such as ferrite, magnetite, iron, nickel, cobalt, and alloys thereof. The average particle size of the magnetic material is preferably 0.1 μm to 1 μm. The content of the magnetic material is preferably 10 to 70 parts by weight with respect to 100 parts by weight of the toner.

  Further, as the carrier used in the two-component developer, known ones can be used, for example, magnetic particles such as iron powder, ferrite powder, nickel powder, magnetite powder, or the surface of these magnetic particles is a fluorine resin, Examples thereof include those treated with a vinyl resin, a silicone resin, or the like, or magnetic particle-dispersed resin particles in which magnetic particles are dispersed in the resin. The average particle size of these magnetic carriers is preferably 20 μm to 70 μm.

  Examples of the coating material on the carrier surface include amino resins such as urea-formaldehyde resin, melamine resin, benzoguanamine resin, urea resin, polyamide resin, and epoxy resin. Polyvinyl and polyvinylidene resins such as acrylic resins, polymethyl methacrylate resins, polyacrylonitrile resins, polyvinyl acetate resins, polyvinyl alcohol resins, polyvinyl butyral resins, polystyrene resins and styrene acrylic copolymer resins, Halogenated olefin resins such as vinyl, polyester resins such as polyethylene terephthalate resin and polybutylene terephthalate resin, polycarbonate resins, polyethylene resins, polyvinyl fluoride resins, polyvinylidene fluoride resins, polytrifluoroethylene resins, polyhexafluoro Propylene resin, copolymer of vinylidene fluoride and acrylic monomer, copolymer of vinylidene fluoride and vinyl fluoride, tetrafluoroethylene and vinylidene fluoride And fluoro such as terpolymers of non-fluoride monomers including, and silicone resins.

  Moreover, you may make conductive powder etc. contain in coating resin as needed. As the conductive powder, metal powder, carbon black, titanium oxide, tin oxide, zinc oxide or the like can be used. These conductive fine particles preferably have an average particle diameter of 1 μm or less. When the average particle diameter is larger than 1 μm, it becomes difficult to control electric resistance.

  As described above, the two-component developer of the present invention can be used by adding inorganic fine powder to the toner as a fluidity improver.

  Further, the developer of the present invention may further contain other additives, for example, a lubricant powder such as Teflon (registered trademark) powder, zinc stearate powder, polyvinylidene fluoride powder, or the like within a range that does not substantially adversely affect the developer. A small amount of a polishing agent such as cerium oxide powder, silicon carbide powder or strontium titanate powder, or a conductivity imparting agent such as carbon black powder, zinc oxide powder or tin oxide powder can be used as a developability improver.

  Next, an image forming apparatus using the electrostatic charge developing toner according to the present invention will be described with reference to FIG. FIG. 7 is a diagram showing a schematic configuration of an image forming apparatus according to an embodiment of the present invention.

  As shown in FIG. 7, drum-shaped photoconductors 10Y and 10M, which are image carriers for yellow (Y), magenta (M), cyan (C), and black (B), are included in the image forming unit 20. 10C and 10B are arranged in parallel. That is, the image forming unit 20 is a tandem color laser copying machine. The toner images of the respective colors formed by these photoconductors 10Y, 10M, 10C, and 10B are supported on an endless transport belt 22 that is stretched around support rollers 21A and 21B and transported in the direction of arrow A. A four-color toner image is formed by being superimposed and transferred onto a sheet P such as transfer paper conveyed in the direction of arrow A.

  A paper feed roller 23 is provided near the bottom of the image forming unit 20. When the paper feed roller 23 rotates, the sheets P are sent out from the paper feed cassette 24 one by one. The sheet P sent out from the paper feed cassette 24 is conveyed to the registration roller 25, temporarily stopped by the registration roller 25, and transferred to the conveyance belt 22 at the timing of transferring the toner images from the photoconductors 10Y, 10M, 10C, and 10B. Be transported.

  The sheet P conveyed along with the conveyance of the conveyance belt 22 is applied with a transfer bias from the transfer roller 26 at the transfer nip between the photoconductors 10Y, 10M, 10C, and 10B and the transfer roller 26, whereby the photoconductors 10Y, 10M, The toner images of the respective colors are stacked and transferred from 10C and 10B. In this way, the sheet P on which the color toner images transferred by stacking the four color toner images are transferred to the fixing device 27. In the fixing device 27, the color toner image is fixed on the sheet P by being heated and pressurized. Then, the sheet P that has been subjected to the fixing process by the fixing device 27 is discharged to the discharge stack portion H by the discharge roller pair 28.

  The optical writing unit 29 includes a light source, a polygon mirror, an f-θ lens, a reflection mirror, and the like, and outputs a laser beam LY, LM, LC, LB corresponding to each color image data based on the image data. Irradiate the surface of 10Y, 10M, 10C, 10B. Then, the surface potential of the photoreceptors 10Y, 10M, 10C, and 10B uniformly charged by the charging device 30 is attenuated at the portions irradiated with the laser beams LY, LM, LC, and LB. By this attenuation, electrostatic latent images corresponding to the respective color images are formed on the surfaces of the photoreceptors 10Y, 10M, 10C, and 10B. The electrostatic latent images formed in this way are developed by the developing devices 11Y, 11M, 11C, and 11B to form toner images of the respective colors. These developing devices 11Y, 11M, 11C, and 11B are provided with bottle-shaped toner cartridges 31Y, 31M, 31C, and 31B that supply the respective toners to the developing devices 11Y, 11M, 11C, and 11B, respectively.

  Further, as described above, the toner images formed on the photoconductors 10Y, 10M, 10C, and 10B remain on the surfaces of the photoconductors 10Y, 10M, 10C, and 10B after being transferred to the sheet P. Therefore, the surfaces of the photoconductors 10Y, 10M, 10C, and 10B are cleaned by the cleaning device 32. Then, after a lubricant is applied to the surfaces of the photoreceptors 10Y, 10M, 10C, and 10B by a lubricant application device (not shown) disposed in the cleaning device 32, the charge is removed by a charge remover (not shown) and charged again. The device 30 is uniformly charged and returns to the initial state.

  In the developing devices 11Y, 11M, 11C, and 11B in this image forming apparatus, the electrostatic charge developing toner manufactured as described above is used as the toner of the two-component developer. Therefore, the obtained toner image is a high-quality image with good dot reproducibility. In addition, the toner fluidity is good, and the toner is smoothly supplied from the toner cartridges 31Y, 31M, 31C, and 31B to the developing devices 11Y, 11M, 11C, and 11B.

  Examples of the electrostatic charge developing toner according to the present invention will be described below, but this does not limit the present invention. In addition, this time, the toner composition, the toner production method, and the toner with different mixing conditions were produced, and the particle surface shape of the obtained toner was evaluated using the above-described evaluation method (K value) used in the present invention. . In this case, the chargeability of the toner was evaluated using an E-spart device (manufactured by Hosokawa Micron Corporation), and the dot reproducibility was evaluated in five stages (rank 1: bad → rank 5: good) as the roughness of the image. The K value was determined as an average of values measured repeatedly 10 times. Further, running characteristics (toner transportability during running of 20,000 sheets) were evaluated based on the presence or absence of changes in image quality. The toner charge amount was measured under the following conditions, and the average value of the toner charge amount Q / d value under the same charge condition was measured.

-Carrier diameter during charging: 35 μm
-Toner density during charging: 7%
-Container size when charging: 25mmφ x 30mm length-Container rotation speed when charging: 280rpm
・ Charging container rotation time: 10 min
-Number of particles measured with E-spart device: 3000

  Further, the circularity of the toner (base material) before being treated with the additive was measured as an average circularity by a flow type particle image analyzer FPIA-1000 (manufactured by Toa Medical Electronics Co., Ltd.). Further, the coverage of the additive was obtained from the area occupied by the additive on the surface of the toner particle using an SEM image of the toner particle. All parts in the following formulations are parts by weight.

[Example 1]
Resin: Polyester resin (Propylene oxide adduct of bisphenol A, polyester synthesized from terephthalic acid, succinic acid derivative) 100 parts Colorant: Magenta pigment (CI Pigment Red 122) (Hostaperm Pink E; manufactured by Clariant) 3 5 parts Charge control agent: Zinc salicylate (Bontron E84, manufactured by Orient Chemical Co., Ltd.) 5 parts Release agent: Low molecular weight polyethylene 5 parts

  After sufficiently mixing the raw materials with a mixer, the raw materials were melt kneaded with a twin screw extruder at a barrel temperature of 110 ° C. and a kneader rotating speed of 100 rpm. The kneaded product is cooled and rolled, coarsely pulverized with a cutter mill, pulverized with a fine pulverizer using a jet stream, and then classified into a particle size distribution with an average particle size of 6.3 μm using a swirling air classifier. Particles were obtained. Further, an additive was mixed with 100 parts of the base colored particles under the following mixing conditions to produce a toner.

Additive: Silica fine powder 1.4 parts
(R972; manufactured by Nippon Aerosil Co., Ltd., average particle size 10 nm)
Titanium oxide fine powder 0.3 part
(MT-150A; manufactured by Teica, average particle size 50 nm)
Mixing rotation speed 2200rpm
Mixing time 150 sec
Mixer Q mixer

  After the toner was manufactured, the toner surface shape and the toner charge amount were measured by the E-Spart method according to the evaluation method of the present invention. The toner obtained by the above production method was mixed in a ratio of 3 parts to 97 parts of a carrier to produce a two-component developer. The obtained developer was an OPC drum photosensitive member as an image carrier, and set in a copying machine as blade cleaning as a cleaning device, and an image evaluation experiment and a running experiment were performed.

[Example 2]
Kneading, pulverization, and classification were carried out using the same raw materials and production method as in Example 1, and classification was made into a particle size distribution with an average particle size of 6.3 μm to obtain base colored particles. Further, an additive was mixed with 100 parts of the base colored particles under the following mixing conditions to produce a toner.

Additive Silica fine powder 1.6 parts
(R972; manufactured by Nippon Aerosil Co., Ltd.)
Titanium oxide fine powder 0.3 part
(MT-150A; manufactured by Teika)
Mixing rotation speed 2200rpm
Mixing time 150 sec
Mixer Q mixer

  After the toner was manufactured, the toner surface shape and the toner charge amount were measured by the E-Spart method according to the evaluation method of the present invention. The two-component developer was manufactured by mixing the toner obtained by the above production method in a ratio of 3 parts with respect to 97 parts of the carrier. The obtained developer was an OPC drum photosensitive member as an image carrier, and set in a copying machine as blade cleaning as a cleaning device, and an image evaluation experiment and a running experiment were performed.

Example 3
Kneading, pulverization, and classification were carried out using the same raw materials and production method as in Example 1, and classification was made into a particle size distribution with an average particle size of 6.3 μm to obtain base colored particles. Further, an additive was mixed with 100 parts of the base colored particles under the following mixing conditions to produce a toner.

Additive Silica fine powder 1.8 parts
(R972; manufactured by Nippon Aerosil Co., Ltd.)
Titanium oxide fine powder 0.3 part
(MT-150A; manufactured by Teika)
Mixing rotation speed 2200rpm
Mixing time 150 sec
Mixer Q mixer

  After the toner was manufactured, the toner surface shape and the toner charge amount were measured by the E-Spart method according to the evaluation method of the present invention. The toner obtained by the above production method was mixed in a ratio of 3 parts to 97 parts of a carrier to produce a two-component developer. The obtained developer was an OPC drum photosensitive member as an image carrier, and set in a copying machine as blade cleaning as a cleaning device, and an image evaluation experiment and a running experiment were performed.

Example 4
Kneading, pulverization, and classification were carried out using the same raw materials and production method as in Example 1, and classification was made into a particle size distribution with an average particle size of 6.3 μm to obtain base colored particles. Further, an additive was mixed with 100 parts of the base colored particles under the following mixing conditions to produce a toner.

Additive silica fine powder 2.0 parts
(R972; manufactured by Nippon Aerosil Co., Ltd.)
Titanium oxide fine powder 0.3 part
(MT-150A; manufactured by Teika)
Mixing rotation speed 2200rpm
Mixing time 150 sec
Mixer Q mixer

  After the toner was manufactured, the toner surface shape and the toner charge amount were measured by the E-Spart method according to the evaluation method of the present invention. The toner obtained by the above production method was mixed in a ratio of 3 parts to 97 parts of a carrier to produce a two-component developer. The obtained developer was an OPC drum photosensitive member as an image carrier, and set in a copying machine as blade cleaning as a cleaning device, and an image evaluation experiment and a running experiment were performed.

Example 5
(Toner binder synthesis)
724 parts of bisphenol A ethylene oxide 2-mole adduct, 276 parts of isophthalic acid and 2 parts of dibutyltin oxide were placed in a reaction vessel equipped with a cooling pipe, a stirrer and a nitrogen introduction pipe, and reacted at 230 ° C. under normal pressure for 8 hours. The reaction was further carried out at a reduced pressure of 10 to 15 mmHg for 5 hours, followed by cooling to 160 ° C., and 32 parts of phthalic anhydride was added thereto and reacted for 2 hours. Subsequently, it cooled to 80 degreeC and reacted with 188 parts of isophorone diisocyanate in ethyl acetate for 2 hours, and the isocyanate containing prepolymer I was obtained. Next, 267 parts of Prepolymer I and 14 parts of isophoronediamine were reacted at 50 ° C. for 2 hours to obtain a urea-modified polyester I having a weight average molecular weight of 64,000.

  In the same manner as above, 724 parts of bisphenol A ethylene oxide 2-mole adduct and 276 parts of terephthalic acid were polycondensed at 230 ° C. for 8 hours under normal pressure, and then reacted for 5 hours at a reduced pressure of 10 to 15 mmHg. An unfinished polyester (A) was obtained. 200 parts of urea-modified polyester I and 800 parts of unmodified polyester (A) are dissolved and mixed in 2000 parts of an ethyl acetate / MEK (1/1) mixed solvent to obtain an ethyl acetate / MEK solution of toner binder (1). It was. Part of the mixture was dried under reduced pressure to isolate toner binder (1). As a result of analysis, Tg was 62 ° C.

(Manufacture of toner)
Toner binder (1) in ethyl acetate / MEK solution 240 parts Pentaerythritol tetrabehenate (melt viscosity 25 cps) 20 parts Carbon black (# 44; manufactured by Mitsubishi Chemical Corporation) 7 parts

  The raw materials were stirred in a beaker at 12000 rpm with a TK homomixer at 60 ° C., and uniformly dissolved and dispersed to produce a toner material solution.

706 parts of ion-exchanged water 10% suspension of hydroxyapatite (Super Chemical 10 manufactured by Nippon Chemical Industry Co., Ltd.)
294 parts Sodium dodecylbenzenesulfonate 0.2 part The above raw materials were placed in a beaker and dissolved uniformly. Thereafter, the temperature was raised to 60 ° C., and the toner material solution was added and stirred for 10 minutes while stirring at 11000 rpm with a TK homomixer. Next, this mixed solution was transferred to a flask equipped with a stirrer and a thermometer, heated to 30 ° C., the solvent was removed under reduced pressure, filtered, washed, dried, and then subjected to air classification to obtain base colored particles. . The volume average particle diameter was 6.0 μm. To 100 parts of the base colored particles, an additive was mixed under the following mixing conditions to obtain a toner.

Additive Silica fine powder 1.4 parts
(R972; manufactured by Nippon Aerosil Co., Ltd.)
Titanium oxide fine powder 0.3 part
(MT-150A; manufactured by Teika)
Mixing rotation speed 2100rpm
Mixing time 150 sec
Mixer Q mixer

  After the toner was manufactured, the toner surface shape and the toner charge amount were measured by the E-Spart method according to the evaluation method of the present invention. The toner obtained by the above production method was mixed in a ratio of 3 parts to 97 parts of a carrier to produce a two-component developer. The obtained developer was an OPC drum photosensitive member as an image carrier, and set in a copying machine as blade cleaning as a cleaning device, and an image evaluation experiment and a running experiment were performed.

Example 6
Powders were produced and classified by the same raw materials and production method as in Example 5, and classified into a particle size distribution having an average particle size of 6.0 μm to obtain base colored particles. Further, an additive was mixed with 100 parts of the base colored particles under the following mixing conditions to produce a toner.

Additive Silica fine powder 1.6 parts
(R972; manufactured by Nippon Aerosil Co., Ltd.)
Titanium oxide fine powder 0.3 part
(MT-150A; manufactured by Teika)
Mixing rotation speed 2100rpm
Mixing time 150 sec
Mixer Q mixer

  After the toner was manufactured, the toner surface shape and the toner charge amount were measured by the E-Spart method according to the evaluation method of the present invention. The toner obtained by the above production method was mixed in a ratio of 3 parts to 97 parts of a carrier to produce a two-component developer. The obtained developer was an OPC drum photosensitive member as an image carrier, and set in a copying machine as blade cleaning as a cleaning device, and an image evaluation experiment and a running experiment were performed.

Example 7
Powders were produced and classified by the same raw materials and production methods as in Example 5, and classified into a particle size distribution with an average particle size of 6.0 μm. Further, an additive was mixed with 100 parts of the base colored particles under the following mixing conditions to produce a toner.

Additive Silica fine powder 1.8 parts
(R972; manufactured by Nippon Aerosil Co., Ltd.)
Titanium oxide fine powder 0.3 part
(MT-150A; manufactured by Teika)
Mixing rotation speed 2100rpm
Mixing time 150 sec
Mixer Q mixer

  After the toner was manufactured, the toner surface shape and the toner charge amount were measured by the E-Spart method according to the evaluation method of the present invention. The toner obtained by the above production method was mixed in a ratio of 3 parts to 97 parts of a carrier to produce a two-component developer. The obtained developer was an OPC drum photosensitive member as an image carrier, and set in a copying machine as blade cleaning as a cleaning device, and an image evaluation experiment and a running experiment were performed.

Example 8
Powders were produced and classified by the same raw materials and production method as in Example 5, and classified into a particle size distribution having an average particle size of 6.0 μm to obtain base colored particles. Further, an additive was mixed with 100 parts of the base colored particles under the following mixing conditions to produce a toner.

Additive silica fine powder 2.0 parts
(R972; manufactured by Nippon Aerosil Co., Ltd.)
Titanium oxide fine powder 0.3 part
(MT-150A; manufactured by Teika)
Mixing rotation speed 2100rpm
Mixing time 150 sec
Mixer Q mixer

  After the toner was manufactured, the toner surface shape and the toner charge amount were measured by the E-Spart method according to the evaluation method of the present invention. The toner obtained by the above production method was mixed in a ratio of 3 parts to 97 parts of a carrier to produce a two-component developer. The obtained developer was an OPC drum photosensitive member as an image carrier, and set in a copying machine as blade cleaning as a cleaning device, and an image evaluation experiment and a running experiment were performed.

Example 9
Resin: Polyester resin (Propylene oxide adduct of bisphenol A, polyester synthesized from terephthalic acid, succinic acid derivative) 100 parts Colorant: Copper phthalocyanine blue pigment (CI Pigment Blue 15: 3) (Lionol Blue FG-7351; Toyo Ink Co., Ltd.) 4 parts Charge control agent: Zinc salicylate (Bontron E84; Orient Chemical Co., Ltd.) 5 parts

  The raw materials were sufficiently mixed with a mixer, and then melt kneaded with a twin screw extruder at a barrel temperature of 110 ° C. and a kneader rotation speed of 100 rpm. The kneaded product is cooled and rolled, coarsely pulverized with a cutter mill, pulverized with a fine pulverizer using a jet stream, and then classified into a particle size distribution with an average particle size of 6.7 μm using a swirl type air classifier. Particles were obtained. Further, an additive was mixed with 100 parts of the base colored particles under the following mixing conditions to produce a toner.

Additive Silica fine powder 1.6 parts
(R972; manufactured by Nippon Aerosil Co., Ltd.)
Titanium oxide fine powder 0.3 part
(MT-150A; manufactured by Teika)
Mixing speed 1800rpm
Mixing time 150 sec
Blender θ Composer

  After the toner was manufactured, the toner surface shape and the toner charge amount were measured by the E-Spart method according to the evaluation method of the present invention. The obtained developer was an OPC drum photosensitive member as an image carrier, and set in a copying machine as blade cleaning as a cleaning device, and an image evaluation experiment and a running experiment were performed.

Example 10
Kneading, pulverization, and classification were carried out using the same raw materials and production method as in Example 9, and classification was performed to obtain a particle size distribution having an average particle diameter of 6.7 μm to obtain base colored particles. Further, an additive was mixed with 100 parts of the base colored particles under the following mixing conditions to produce a toner.

Additive Silica fine powder 1.8 parts
(R972; manufactured by Nippon Aerosil Co., Ltd.)
Titanium oxide fine powder 0.3 part
(MT-150A; manufactured by Teika)
Mixing speed 1800rpm
Mixing time 150 sec
Blender θ Composer

  After the toner was manufactured, the toner surface shape and the toner charge amount were measured by the E-Spart method according to the evaluation method of the present invention. The obtained developer was an OPC drum photosensitive member as an image carrier, and set in a copying machine as blade cleaning as a cleaning device, and an image evaluation experiment and a running experiment were performed.

Example 11
Kneading, pulverization, and classification were carried out using the same raw materials and production method as in Example 9, and classification was performed to obtain a particle size distribution having an average particle diameter of 6.7 μm to obtain base colored particles. Further, an additive was mixed with 100 parts of the base colored particles under the following mixing conditions to produce a toner.

Additive silica fine powder 2.0 parts
(R972; manufactured by Nippon Aerosil Co., Ltd.)
Titanium oxide fine powder 0.3 part
(MT-150A; manufactured by Teika)
Mixing speed 1800rpm
Mixing time 150 sec
Blender θ Composer

  After the toner was manufactured, the toner surface shape and the toner charge amount were measured by the E-Spart method according to the evaluation method of the present invention. The obtained developer was an OPC drum photosensitive member as an image carrier, and set in a copying machine as blade cleaning as a cleaning device, and an image evaluation experiment and a running experiment were performed.

[Comparative Example 1]
Kneading, pulverization, and classification were carried out using the same raw materials and production method as in Example 1, and classification was made into a particle size distribution with an average particle size of 6.3 μm to obtain base colored particles. Further, an additive was mixed with 100 parts of the base colored particles under the following mixing conditions to produce a toner.

Additive Silica fine powder 1.0 part
(R972; manufactured by Nippon Aerosil Co., Ltd.)
Mixing speed 750rpm
Mixing time 120sec
Mixer super mixer

  After the toner was manufactured, the toner surface shape and the toner charge amount were measured by the E-Spart method according to the evaluation method of the present invention. The toner obtained by the above production method was mixed in a ratio of 3 parts to 97 parts of a carrier to produce a two-component developer. The obtained developer was an OPC drum photosensitive member as an image carrier, and set in a copying machine as blade cleaning as a cleaning device, and an image evaluation experiment and a running experiment were performed. The results are shown in Table 1.

[Comparative Example 2]
Powders were produced and classified by the same raw materials and production method as in Example 5, and classified into a particle size distribution having an average particle size of 6.0 μm to obtain base colored particles. Further, an additive was mixed with 100 parts of the base colored particles under the following mixing conditions to produce a toner.

Additive Silica fine powder 1.0 part
(R972; manufactured by Nippon Aerosil Co., Ltd.)
Mixing speed 750rpm
Mixing time 120sec
Mixer super mixer

  After the toner was manufactured, the toner surface shape and the toner charge amount were measured by the E-Spart method according to the evaluation method of the present invention. The toner obtained by the above production method was mixed in a ratio of 3 parts to 97 parts of a carrier to produce a two-component developer. The obtained developer was an OPC drum photosensitive member as an image carrier, and set in a copying machine as blade cleaning as a cleaning device, and an image evaluation experiment and a running experiment were performed.

[Comparative Example 3]
Kneading, pulverization, and classification were carried out using the same raw materials and production method as in Example 9, and classification was performed to obtain a particle size distribution having an average particle diameter of 6.7 μm to obtain base colored particles. Further, an additive was mixed with 100 parts of the base colored particles under the following mixing conditions to produce a toner.

Additives Silica fine powder 3.5 parts
(R972; manufactured by Nippon Aerosil Co., Ltd.)
Mixing speed 750rpm
Mixing time 120sec
Mixer super mixer

  After the toner was manufactured, the toner surface shape and the toner charge amount were measured by the E-Spart method according to the evaluation method of the present invention. The obtained developer was an OPC drum photosensitive member as an image carrier, and set in a copying machine as blade cleaning as a cleaning device, and an image evaluation experiment and a running experiment were performed.

  For the electrostatic charge developing toners obtained in the above Examples and Comparative Examples, the K value average value, the coverage average value, the particle shape (circularity) charging characteristics, the interparticle force average value, and these toners are used. Table 1 shows the evaluation results of the toner image dot reproducibility evaluation and toner transferability evaluation during running of 20,000 sheets.

  As apparent from the above results, in Comparative Examples 1 and 2, the K values are 1.0245, 1.0265, and less than 1.031, and the charging characteristics are 0.362 (−fC / μm) and 0. It is as low as 392 (−fC / μm). As a result, the dot reproducibility is evaluated as poor as rank 3, and the toner transportability during running of 20,000 sheets is also poor. Moreover, in the thing of the comparative example 3, K value exceeds 1.0556 and 1.040, and a charging characteristic is also as low as 0.285 (-fC / micrometer). As a result, the dot reproducibility is evaluated as poor as rank 3, and the toner transportability during running of 20,000 sheets is also poor.

  On the other hand, in each example according to the present invention, the K value is in the range of 1.031 to 1.040, and the charging characteristic is also good at 0.5 (−fC / μm) or more. As a result, it is apparent that the dot reproducibility evaluation is rank 4 or higher, and the toner transportability during 20,000-sheet running is also good.

2 Evaluation Device 2a SEM Device 2b K Value Analysis Device 3 Mixer 4 Toner Supply Port 5 Additive Supply Port 6 Extraction Port 7 Discharge Port 9 Container 10, 10Y, 10M, 10C, 10B Photoconductor 11, 11Y, 11M, 11C, 11B Developing device 12 Developing roller 13 Doctor roller 14 Supply roller 15 Stirring roller 16 Toner replenishment hopper 17 Toner replenishment roller 18 Case 20 Image forming unit 22 Conveying belt 25 Registration roller 26 Transfer roller 27 Fixing device 29 Optical unit 30 Charging device 31Y , 31M, 31C, 31B Toner cartridge 32 Cleaning device

Japanese Patent Laid-Open No. 11-295989 JP 2007-78966 A

Claims (20)

At least particles of toner composed of resin and pigment are photographed with a scanning electron microscope, and based on the photographed image of the toner particles, the contour line of the toner particle surface is 1/6000 to 1/1 / of the particle diameter of the toner particles. The number of squares N (a) formed at that time is determined by dividing the square by a on one side to be 20, and the relationship between N (a) and a satisfies the following expression (1), and the (1) The relationship between the average value of K values obtained using the equation and the toner charge amount Q / d (where d indicates the particle size of the toner) is obtained, and the K value at which the Q / d value is greater than a predetermined value. The toner for developing electrostatic charge, wherein the toner is 1.031 to 1.040.
N (a) ∝a- ^K (1)   2. The electrostatic charge developing toner according to claim 1, wherein a predetermined value of the toner charge amount Q / d is 0.5 (−fC / μm).   3. The electrostatic charge developing toner according to claim 1, wherein when the interparticle force of the toner is measured by an AFM colloid probe method, an average value of the interparticle force of the toner is 1 nN to 30 nN.   The electrostatic charge developing toner according to claim 1, wherein the toner has an average circularity of 0.90 to 0.99.   5. The toner according to claim 1, wherein an additive comprising at least silicon dioxide having an average particle diameter of 10 nm to 200 nm is adhered or fixed to the surface of the toner at a coverage of 20 to 30%. The toner for developing an electrostatic charge as described.   6. The electrostatic charge developing toner according to claim 1, wherein the additive adhered or fixed to the surface of the toner contains titanium dioxide having an average particle diameter of 10 nm to 200 nm.   The electrostatic charge developing toner according to claim 1, wherein the toner contains a charge control agent.   The electrostatic charge developing toner according to claim 1, wherein the toner contains a release agent. 9. The electrostatic charge developing toner according to claim 1, wherein at least one of the resins is a crystalline polyester represented by the following general formula (1).
^{[-O-CO-CR 1 =} CR 2 -CO-O- (CH 2) n-] m (1)
(In the formula, n and m are the number of repeating units, and R ¹ and R ² represent a hydrogen atom or a hydrocarbon group.)   The electrostatic charge developing toner according to claim 1, wherein the toner has an interparticle force of 1 to 30 nN as measured by an atomic force microscope.   The toner for electrostatic charge development according to claim 1, wherein the toner is produced by a polymerization method using a composition containing a monomer or a prepolymer and a pigment.   The electrostatic charge developing toner according to claim 1, wherein the toner is prepared by kneading a composition containing a resin and a pigment, then cooling and pulverizing the toner. .   A developing method comprising performing contact or non-contact development using the electrostatic charge developing toner according to claim 1.   A developing method comprising a two-component developing method using a carrier having a particle diameter of 20 to 70 µm together with the electrostatic charge developing toner according to any one of claims 1 to 12.   A toner cartridge containing the electrostatic charge developing toner according to claim 1.   A process cartridge containing the electrostatic charge developing toner according to claim 1.   An electrostatic charge developing toner according to claim 1 is accommodated, and the toner is supplied to an electrostatic latent image formed on an image carrier to form the electrostatic latent image into a toner image. A developing device.   An image forming apparatus comprising: an image carrier; and a developing device that supplies toner to the electrostatic latent image formed on the image carrier to convert the toner electrostatic latent image into a toner image. An image forming apparatus comprising the developing device according to claim 17. At least particles of toner composed of resin and pigment are photographed with a scanning electron microscope, and based on the photographed image of the toner particles, the contour line of the toner particle surface is 1/6000 to 1/1 / of the particle diameter of the toner particles. The number of squares N (a) formed at that time is determined by dividing the square by a on one side to be 20, and the relationship between N (a) and a satisfies the following expression (1), and the (1) The relationship between the average value of K values obtained using the equation and the toner charge amount Q / d (where d indicates the particle size of the toner) is obtained, and the K value at which the Q / d value is greater than a predetermined value. A toner evaluation method for electrostatic charge development, wherein the surface shape of toner particles is evaluated by:
N (a) ∝a- ^K (1) 20. The electrostatic charge developing toner according to claim 19, wherein the surface shape of the toner particles is evaluated based on a value of K where the predetermined value of the toner charge amount Q / d is 0.5 (−fC / μm). Evaluation methods.