JP6578903B2 - Toner, toner storage unit and image forming apparatus - Google Patents

Description

  The present invention relates to a toner, a toner storage unit, and an image forming apparatus.

  In electrophotographic image formation, an electrostatic charge image (latent image) is formed on an electrostatic latent image carrier, charged toner is conveyed by a developer carrier, and the latent image is developed to form a toner image. After the formation, the toner image is transferred onto a recording medium such as paper and fixed by a method such as heating to obtain an output image. Further, a technique is known in which toner remaining on an electrostatic latent image carrier after transfer is recovered from the electrostatic latent image carrier by a cleaning member and discharged to a waste toner storage unit.

  In the heat-fixing type image forming apparatus, since a large amount of electric power is required in the process of heat-melting the toner and fixing it on a recording medium such as paper, the toner has a low-temperature fixability from the viewpoint of energy saving. Is one of the important characteristics. In addition, stable charging characteristics and heat-resistant storage are required to continue outputting images with a constant image quality even under harsh usage conditions such as fluctuations in the operating temperature and humidity of the image forming apparatus and continuous output of a large number of images. It is also important to have sex.

In order to improve the low-temperature fixability of the toner, it is necessary to control the molecular weight, molecular weight distribution, and thermal characteristics of the binder resin that occupies most of the toner. For example, Patent Document 1 contains at least two kinds of resins having different softening points of 25 ° C. or more, and the molecular weight distribution by GPC determined by the THF-soluble content of each resin is between 1,000 and 10,000. In addition, the distribution has a half-value width of 15,000 or less and a distribution of chloroform insoluble content of 5 to 40%, thereby exhibiting excellent low-temperature fixability, and resistance to hot offset, and Toners excellent in heat-resistant storage stability have been proposed.
However, since the low molecular weight components increase due to the low molecular weight of the binder resin, these components contaminate the surface of the charging member and the carrier, or these components themselves absorb moisture under high humidity. There has been a problem of deteriorating the charging stability of the toner.

On the other hand, in order to improve the charging stability of the toner, in general, a hydrophobic additive is externally added to the toner surface to suppress a decrease in charging of the toner under high humidity. For example, a method for removing a component in the toner that lowers the toner property and a method for improving the contamination resistance of the toner component with respect to the charging member or the carrier are effective.
For example, in Patent Document 2, the odor caused by the low molecular weight component is controlled by controlling the component ratio of the molecular weight of 500 to 1,000 derived from the binder resin in the GPC of the toner and the component ratio of the molecular weight of 500 or less to a specific range. It has been proposed that it is possible to suppress the air pollution and the in-flight contamination. Patent Document 3 proposes that the contamination of the developing member or the like due to the low molecular weight component can be suppressed by controlling the content of the component having a molecular weight of 500 or less in the GPC of the binder resin.
However, in these proposals, low molecular weight components that work effectively on low temperature fixability are actively removed, so that the low temperature fixability is greatly deteriorated.

Further, in Patent Document 4, by specifying the glass transition temperature of the toner at a predetermined temperature increase rate in DSC measurement, both low-temperature fixability and storability are achieved, and at a specific wavelength of the toner ethyl acetate solution. By defining the relationship between absorbance and concentration, the composition of the polyester resin as the binder resin, and the acid value / hydroxyl value of the resin, the amount of the moisture absorbing component present on the toner surface and the moisture absorbing component derived from the binder resin can be reduced. It has been proposed that the charge stability of the toner can be improved by reducing the charge.
However, in this proposal, the low molecular weight component that works effectively for the low temperature fixability is removed, so that the level of the low temperature fixability is not yet reached, and the molecular weight 1000 to 2000 deteriorates the charging stability. Since acid dimers and acid trimers of a certain degree are not considered, the charging stability has not reached a sufficient level.

Thus, low-temperature fixability, heat-resistant storage stability, and charging stability are in a trade-off relationship, and a toner that can satisfy all of these conditions has not yet been achieved.
In addition, if the components such as unreacted residual monomer or low polymer dimer and trimer contained in the binder resin are simply reduced within the range where low temperature fixability can be maintained, the adhesive component between the toner particles during fixing As a result, some of the components that act will be removed, and there is a concern that the strength of the formed fixed image will be reduced. Therefore, both low-temperature fixability, heat-resistant storage stability, and charging stability are compatible. It is very difficult.

In Patent Document 5, by using hexafluoroisopropanol (HFIP) that is sufficiently soluble up to the highly crosslinked resin component, in addition to the relatively low molecular weight region that has been evaluated with conventional solvents such as tetrahydrofuran (THF), GPC makes it possible to evaluate molecular weight distribution up to highly crosslinked components (high molecular weight components) that were insoluble in any of these solvents, and by adjusting the toner formulation and manufacturing process based on this evaluation method, Corresponding, it has a sufficient fixing temperature range, good offset resistance and wrapping property, sufficient friction peeling strength after fixing, sufficient gloss, and fixing even after printing tens of thousands of sheets It has been proposed that a toner, a developer, an image forming apparatus, and an image forming method that do not contaminate the apparatus and the image can be provided.
However, in the evaluation method using hexafluoroisopropanol (HFIP), only the general ones such as Mn, Mw / Mn, and the ratio of molecular weight of 100,000 or more have attracted attention. And high-temperature storage stability, charging stability, fixed image strength, etc. have not been achieved at the same time.

  The present invention has been made in view of the above, and an object thereof is to provide a toner excellent in low-temperature fixability, heat-resistant storage stability, charging stability, and image quality.

In order to solve the above problems, the present invention is a toner containing at least a binder resin and a release agent, in a molecular weight distribution measured by GPC of a hexafluoroisopropanol (HFIP) soluble component of the toner, When the peak top molecular weight of the main peak (P0) is in the range of 3,000 to 10,000 and the molecular weight is in the range of 250 to 2,500, the peak top (P1) of any peak is selected. The difference between the maximum value and the minimum value of the peak intensity defined below in the range of the molecular weight ± 100 of the peak top (P1) is 30 or less, and the intensity is 30 in the molecular weight range of 15,000 to 35,000. There is a peak top (P2) or shoulder peak (P2 ′) of a peak of 80 or less, and the toner tetrahydro The molecular weight distribution measured by GPC of a furan (THF) soluble component is characterized by having no peak or shoulder peak with a peak top in the molecular weight range of 15,000 to 35,000.
Peak intensity: GPC measurement is plotted with a molecular weight distribution curve in which the vertical axis is the intensity and the horizontal axis is the molecular weight, and the peak intensity value that is maximum in the range of the molecular weight of 1,000 to 10,000 is 100. Relative value

  According to the present invention, it is possible to provide a toner excellent in low-temperature fixability, heat-resistant storage stability, charging stability and image quality.

It is a figure which shows an example of the flow curve of the toner measured using the elevated flow tester. 1 is a schematic diagram illustrating an example of an image forming apparatus according to the present invention. It is a schematic diagram which shows the other example of the image forming apparatus which concerns on this invention. It is a schematic diagram which shows the other example of the image forming apparatus which concerns on this invention. It is a schematic diagram which shows the other example of the image forming apparatus which concerns on this invention. FIG. 3 is a schematic explanatory diagram illustrating an example of a recording medium pressing force measuring apparatus for evaluating toner separation stability. It is a schematic diagram which shows an example of the evaluation chart in gloss unevenness evaluation. FIG. 6 is a diagram for explaining a main peak (P0), a peak top (P1), a peak top (P2), and a shoulder peak (P2 ′) of toner. FIG. 6 is a diagram for explaining a peak top (P1) of toner.

  Hereinafter, a toner, a toner storage unit, and an image forming apparatus according to the present invention will be described with reference to the drawings. The present invention is not limited to the embodiments described below, and other embodiments, additions, modifications, deletions, and the like can be changed within a range that can be conceived by those skilled in the art, and any aspect is possible. As long as the functions and effects of the present invention are exhibited, the scope of the present invention is included.

(toner)
The present invention relates to a toner containing at least a binder resin and a release agent, and a peak top of a main peak (P0) in a molecular weight distribution measured by GPC of a hexafluoroisopropanol (HFIP) soluble component of the toner. When the peak top (P1) of an arbitrary peak having a molecular weight in the range of 3,000 to 10,000 and a molecular weight in the range of 250 to 2,500 is selected, the molecular weight of the peak top (P1) The peak top (P2) or shoulder of the peak having a difference between the maximum value and the minimum value of the peak intensity in the range of ± 100 is 30 or less and the intensity is in the range of 15,000 to 35,000 in the molecular weight range of 30 to 80. Measured by GPC of tetrahydrofuran (THF) soluble component of the toner having a peak (P2 ′) The molecular weight distribution is characterized by having no peak or shoulder peak with a peak top in the molecular weight range of 15,000 or more and 35,000 or less.
Here, the intensity is plotted by a molecular weight distribution curve in which the vertical axis is intensity and the horizontal axis is molecular weight according to GPC measurement, and the peak intensity value that is maximum in a molecular weight range of 1,000 to 10,000 is 100. Means relative value.
Details will be described below.

  In the present invention, attention is paid to the characteristics of the molecular weight distribution of each soluble component of THF and hexafluoroisopropanol (HFIP).

  In order to improve the low-temperature fixability of the toner, it is necessary to control the toner to have a lower viscosity in a low-temperature region. In the present invention, in order to realize low-temperature fixability, in the hexafluoroisopropanol (HFIP) soluble component, the peak top molecular weight of the main peak (P0) is preferably 10,000 or less. When the peak top molecular weight (P0) of the main peak is larger than 10,000, the toner is not sufficiently lowered in viscosity, and the low-temperature fixability tends to be hindered. Further, when the peak top molecular weight (P0) of the main peak is less than 3,000, the heat resistant storage stability may be deteriorated.

  On the other hand, in order to improve the heat resistant storage stability and charging stability under high humidity of the toner, it is necessary to reduce the low heat characteristic component and the high hygroscopic component contained in the toner. Conventionally, for the purpose of improving heat-resistant storage stability and charging stability, the component ratio of the molecular weight of 500 to 1000 derived from the binder resin and the component ratio of the molecular weight of 500 or less in the gel permeation chromatography (GPC) of the toner have been reduced. .

  However, while studying low-temperature fixing of the toner by lowering the molecular weight of the binder resin, it has been found that it is not sufficient to reduce these low molecular weight components. And, in the molecular weight distribution obtained by GPC measurement of THF-soluble components and hexafluoroisopropanol (HFIP) -soluble components, when a large number of specific molecular weight components are detected as peaks, heat-resistant storage stability, charging stability under high humidity It was found that sex deteriorated.

  This is presumably because the specific peak component forms a domain for each peak, resulting in variations in characteristics in the toner, resulting in deterioration of heat storage stability and charging stability under high humidity. Further, the reduction in the molecular weight of the binder resin tends to cause deformation of the toner with respect to heat or mechanical pressure. In addition, since low molecular weight components in the toner increase, these components contaminate the surface of the charging member and the carrier, and these components themselves absorb moisture under high humidity. There was a problem of worsening.

  As a result of intensive studies in view of the above problems, the present inventors have found that the molecular weight is in the range of 250 to 2,500 in the molecular weight distribution measured by GPC of the hexafluoroisopropanol (HFIP) soluble component of the toner. When the peak top (P1) of an arbitrary peak to be selected is selected, it is important that the difference between the maximum value and the minimum value of the peak intensity in the range of the molecular weight ± 100 of the peak top (P1) is 30 or less. I found it. By doing so, it has been found that low-temperature fixability can be realized by lowering the viscosity of the binder resin, and further deterioration of heat-resistant storage stability and charging stability can be effectively suppressed.

  In the range of the molecular weight ± 100 of the peak top (P1), when the difference between the maximum value and the minimum value exceeds 30, the intensity difference means a peak mainly observed on the low molecular weight side. The peak seen on the low molecular weight side in the molecular weight distribution is mainly caused by low molecular weight components derived from raw materials. For example, the binder resin is derived from an unreacted residual monomer contained in the binder resin, or a dimer or trimer which is a low polymer.

  When the difference between the maximum value and the minimum value exceeds 30, that is, the toner contains a large amount of low molecular weight components, and the low molecular weight components have a characteristic that they are easily melted by heat from the outside. . Therefore, it is easily softened by heat generated from the machine being used, heat during storage, and the like. Therefore, a toner having a large amount of low molecular weight components has poor heat-resistant storage stability, and toner particles are easily aggregated by heat.

  In addition, since low molecular weight components are easily deformed and attached to external pressure, when toners with a large amount of low molecular weight components are used as developers, they can be used for a long time or under high temperature and high humidity. As a result, it adheres to the carrier or the developing member, and the chargeability over time is significantly reduced.

  Therefore, by adopting the present invention, low-temperature fixability can be realized, and further deterioration of heat-resistant storage stability and charging stability can be effectively suppressed. Furthermore, contamination resistance can be improved by appropriately controlling the low molecular weight component. In addition, according to the present invention, the separation stability of the toner can be improved, and both separation stability and high glossiness can be achieved.

  In the present invention, in the molecular weight distribution measured by GPC of the hexafluoroisopropanol (HFIP) soluble component of the toner, the peak top (P1) of an arbitrary peak having a molecular weight in the range of 250 to 2,500 is selected. The difference between the maximum value and the minimum value of the peak intensity in the range of ± 100 of the peak top (P1) molecular weight is 30 or less. The control method is not particularly limited, and examples thereof include a method of replacing the terminal hydrophilic group of the binder resin with a lipophilic group and a method of accelerating the reaction conditions for resin synthesis. The method for substituting the terminal hydrophilic group with a lipophilic group is not particularly limited, and examples thereof include a method of substituting the terminal hydroxyl group with phenoxyacetic acid or benzoic acid. The method for accelerating the reaction conditions for resin synthesis is not particularly limited, and examples include a method of reacting at a high temperature for a long time and increasing the degree of vacuum to remove the monomer.

  However, the present inventors have found that the peak top (P1) of an arbitrary peak having a molecular weight in the range of 250 to 2,500 in the molecular weight distribution measured by GPC of the hexafluoroisopropanol (HFIP) soluble component of the toner. Is selected, the difference between the maximum value and the minimum value of the peak intensity in the range of ± 100 of the peak top (P1) molecular weight is 30 or less to achieve low-temperature fixability by lowering the viscosity of the binder resin, Furthermore, while finding out that deterioration of heat-resistant storage stability and charging stability can be effectively suppressed, it has been newly confirmed that a decrease in strength of a fixed image formed may be reduced as a trade-off.

  As a result of intensive studies on this new problem, the present inventors have made a common monomer in the binder resin forming the main peak (P0), have the same molecular weight, and have high cohesiveness. It has been found that the inclusion of the components makes it possible to achieve both low-temperature fixability, heat-resistant storage stability, charge stability and securing the strength of the fixed image by lowering the viscosity of the binder resin. The characteristics of such a system are shown by the molecular weight distribution measured by GPC of the hexafluoroisopropanol (HFIP) soluble component and the THF soluble component as follows.

  That is, in the toner containing at least a binder resin and a release agent, the peak top molecular weight of the main peak (P0) in the molecular weight distribution measured by GPC of the hexafluoroisopropanol (HFIP) soluble component of the toner is When the peak top (P1) of an arbitrary peak that is in the range of 3,000 to 10,000 and the molecular weight is in the range of 250 to 2,500 is selected, the (P1) molecular weight of the peak top ± 100 The peak top (P2) or shoulder peak (P2) of the peak having a difference between the maximum value and the minimum value of the peak intensity in the range of 30 or less and a molecular weight in the range of 15,000 or more and 35,000 or less and 30 to 80 or less. P2 ') and in the molecular weight distribution measured by GPC of the THF soluble component of the toner The inventors have found that it is important to have no peak or shoulder peak in the molecular weight range of 15,000 or more and 35,000 or less.

  In the toner of the present invention, it is possible to dissolve a molecular weight component having a molecular weight in the range of 15,000 to 35,000 even in THF. Therefore, the THF-soluble component GPC does not have a peak top or shoulder peak in this range, while the hexafluoroisopropanol (HFIP) -soluble component GPC has an intensity of 30 or more and 80 or less. The peak top (P2) or the shoulder peak (P2 ') of this means that components having different states in which the molecular size and shape change due to the difference in solvation of the solvent species are contained.

  In GPC, even if the molecular weights are about the same, the apparent molecular weight differs for samples whose component size and shape change due to solvation in the solvent because the elution time changes. The difference in molecular weight distribution measured by GPC of hexafluoroisopropanol (HFIP) soluble component and THF soluble component having a molecular weight in the range of 15,000 to 35,000 in the present invention is the main peak in HFIP having high solubility. Among the binder resins forming (P0), it can be considered that the molecular size was increased by loosening the molecular chains that existed in a state of high cohesion and high density.

  The intensity of the peak top (P2) or shoulder peak (P2 ′) of the peak in the molecular weight range of 15,000 to 35,000 in GPC of the hexafluoroisopropanol (HFIP) soluble component is 30 to 80. More preferably, it is the range of 45-65. When the strength is less than 30, the amount of the component having high cohesive force is small, which is insufficient for improving the strength of the fixed image. Further, when the strength is greater than 80, the domain is composed only of components having high cohesive force, the physical properties of each toner particle are likely to be non-uniform, and the sharp melt property required for low-temperature fixing is impaired. The strength of the entire fixed image cannot be improved.

  In addition, the GPC of the THF-soluble component has a peak top (P2) or shoulder peak (P2 ′) having a molecular weight in the range of 15,000 or more and 35,000 or less, thereby impairing the low-temperature fixability. As in the present invention, it is difficult to achieve both low-temperature fixability, heat-resistant storage stability, charging stability, and fixed image strength at a high level.

  In the binder resin forming the main peak (P0), there is no particular limitation as to the method of causing the toner to contain a resin component that is composed of a common monomer and has the same molecular weight but enhanced cohesiveness. However, for example, there is a method of using an aliphatic compound having a single bond of 2 to 4 carbon atoms as a main chain as one of the monomers at the time of synthesis of the binder resin. As a method, a toner is prepared from a polyester resin synthesized by using ethylene glycol, diethylene glycol, 1,3-propylene glycol, 1,4-butanediol, or the like.

  The molecular weight distribution measured by GPC of the hexafluoroisopropanol (HFIP) soluble component of the toner is measured as follows.

Gel permeation chromatography (GPC) measuring device: HLC-8220GPC (manufactured by Tosoh Corporation)
Column: TSK GMH _HR (manufactured by Tosoh Corporation)
Temperature: 40 ° C
Solvent: Hexafluoroisopropanol (HFIP) Solution flow rate: 0.2 mL / min
Sample: Hexafluoroisopropanol (HFIP) sample solution adjusted to 0.15% by mass Pretreatment of sample: Toner was dissolved in hexafluoroisopropanol (HFIP) at 0.15% by mass and filtered through a 0.45 μm filter, and the filtrate Is used as a sample.

  The measurement is performed by injecting 10 μL of the HFIP sample solution. The injection amount may be adjusted within a range of 10 to 200 μL, for example, within a range that does not hinder peak separation. In measuring the molecular weight of a sample, the molecular weight distribution of the sample is calculated from the relationship between the logarithmic value of a calibration curve prepared with several types of polymethyl methacrylate standard samples and toluene and the number of counts.

  As a polymethylmethacrylate standard sample for preparing a calibration curve, EasiVial PM polymethylmethacrylate (PL2020-0200) is used, and toluene manufactured by Wako Pure Chemical Industries, Ltd. is used. An RI (refractive index) detector is used as the detector.

  The molecular weight distribution measured by GPC of the THF soluble component of the toner is measured as follows.

Gel permeation chromatography (GPC) measuring device: GPC-8220GPC (manufactured by Tosoh Corporation)
Column: TSK-GEL SUPER HZ2000, TSK-GEL SUPER HZ2500, TSK-GEL SUPER HZ3000
Temperature: 40 ° C
Solvent: THF
Flow rate: 0.35 ml / min
Sample: THF sample solution adjusted to 0.15% by mass Sample pretreatment: The toner was dissolved in tetrahydrofuran THF (containing a stabilizer, manufactured by Wako Pure Chemical Industries, Ltd.) at 0.15 wt% and filtered through a 0.45 μm filter. The filtrate is used as a sample.

  The measurement is performed by injecting 10 μL of the THF sample solution. The injection amount may be adjusted within a range of 10 to 200 μL, for example, within a range that does not hinder peak separation. In measuring the molecular weight of a sample, the molecular weight distribution of the sample is calculated from the relationship between the logarithmic value of a calibration curve prepared from several types of monodisperse polystyrene standard samples and the number of counts.

  As a standard polystyrene sample for preparing a calibration curve, as a standard polystyrene sample for preparing a calibration curve, a TSK standard polystyrene manufactured by Tosoh Corporation having a molecular weight of 37200, 6200, 2500, 589, molecular weights 28400, 20298, 10900, 4782, 1689, 1309 Standard polystyrene and toluene manufactured by Showa Denko are used. An RI (refractive index) detector is used as the detector.

  About the measurement result of hexafluoroisopropanol (HFIP) and THF soluble GPC, the vertical axis is plotted with a molecular weight distribution curve with the intensity on the vertical axis and the molecular weight on the horizontal axis, and the peak intensity in the molecular weight range of 1,000 to 10,000. The intensity of the entire molecular weight distribution curve is corrected with 100 being the maximum value.

8 and 9 are diagrams for explaining the main peak (P0), peak top (P1), peak top (P2) and shoulder peak (P2 ') of toner, and the following P3.
FIG. 9 is a diagram for explaining the definition of the peak top (P1).
The toner of the present invention shown in FIG. 8 has a main peak (P0) near the molecular weight exceeding 3,000 in the molecular weight distribution measured by GPC of the hexafluoroisopropanol (HFIP) soluble component. I understand. The main peak (P0) may have a peak top molecular weight in the range of 3,000 to 10,000, and the graph shown in FIG. 8 is merely an example of the toner of the present invention.
The toner of the present invention has a peak top (P1) in a molecular weight range of 250 or more and 2,500 or less. This P1 is an arbitrary one existing within the molecular weight range, and can be present within the P1 target range in FIG. 8. With reference to FIG. 9, there is a peak top (P1) when the molecular weight exceeds 250. is doing. When this peak top (P1) is selected, the difference between the maximum value and the minimum value of the peak intensity in the range of the molecular weight ± 100 of the peak top (P1) is 30 or less. In the form of FIG. 9, the peak intensity obtained by subtracting 100 from the molecular weight of the peak top (P1) is the minimum value of the peak intensity, and the peak top (P1) itself is the maximum value of the peak intensity. The difference in peak intensity is 30 or less.
The toner of the present invention has a peak top (P2) or a shoulder peak (P2 ′) having a peak intensity of 30 to 80 in the molecular weight range of 15,000 to 35,000. Referring to FIG. 8, a peak top (P2) or a shoulder peak (P2 ′) is confirmed in the target range of P2 and P2 ′.
Further, in the toner of the present invention, as a preferred form, the molecular weight distribution measured by GPC of a hexafluoroisopropanol (HFIP) soluble component has an intensity in the range of molecular weight of 100,000 to 300,000 (P3) of 10 to 30. The range is as follows. Referring to FIG. 8, in the P3 target range, the intensity satisfies the range.

  In the present invention, in the molecular weight distribution measured by GPC of the hexafluoroisopropanol (HFIP) soluble component of the toner, the strength in the molecular weight range of 100,000 to 300,000 (P3) is in the range of 10 to 30. It is preferable to achieve both glossiness and separation resistance while ensuring low-temperature fixability.

  In general, in order to improve the separation resistance, it is necessary to contain a high molecular weight component having a large molecular weight, but as a side effect, there is a concern that the glossiness and low-temperature fixing performance are lowered. In addition, when the amount of the high molecular weight component is simply decreased so as to improve the low temperature fixability and the glossiness, it is difficult to maintain the separation resistance at a required level.

  In the present invention, in the molecular weight distribution measured by GPC of the hexafluoroisopropanol (HFIP) soluble component of the toner, the molecular weight range of 100,000 to 300,000 (P3) contains an intermediate molecular weight component. The low-temperature fixability, glossiness, and separation resistance are compatible at a desirable level. When the strength range is less than 10, an increase in separation resistance tends to be a problem, and when the strength range exceeds 30, the temperature is low. It tends to cause deterioration of fixing characteristics and glossiness.

  In the present invention, the glass transition temperature Tg of the toner is 45 ° C. to 60 ° C., and the weight average molecular weight Mw is 6,000 to 15,000 in the molecular weight distribution by GPC of the THF soluble component of the toner. The molecular weight (Mw) / number average molecular weight (Mn) is preferably 7.5 or less.

  The glass transition temperature Tg of the toner is preferably 45 to 60 ° C. When the Tg is less than 45 ° C., the storage stability in a high temperature and high humidity environment is deteriorated, and problems such as solidification or aggregation, and a decrease in electrification due to surface change are likely to occur. On the other hand, when Tg exceeds 60 ° C., low-temperature fixability may be inhibited. The glass transition temperature Tg is more preferably 50 to 55 ° C.

For example, a differential scanning calorimeter (for example, DSC-6220R: Seiko Instruments Inc.) can be used for measuring Tg of the toner used in the present invention.
As a specific example, after heating from room temperature to 150 ° C. at a temperature rising rate of 10 ° C./min, the sample is left at 150 ° C. for 10 minutes, cooled to room temperature, left for 10 minutes, and again heated to 150 ° C. at 10 ° C. It can be obtained from a curve portion corresponding to a half of the height of the base line below the glass transition point and the height of the base line above the glass transition point.

  In the molecular weight distribution by GPC of the THF soluble component of the toner, the weight average molecular weight Mw is preferably 6,000 to 15,000. When the weight average molecular weight Mw is less than 6,000, the heat resistant storage stability may be deteriorated. Furthermore, since the proportion of low molecular weight components in the toner increases, these components contaminate the surface of the charging member and the carrier, and these components themselves absorb moisture under high humidity, thereby stabilizing the charging of the toner. Sex is likely to deteriorate. When the weight average molecular weight Mw is larger than 15,000, the elasticity of the toner at the time of fixing becomes high and the low-temperature fixing property may be hindered. The weight average molecular weight Mw is more preferably 8,000 to 12,000.

In the molecular weight distribution by GPC of the THF soluble component of the toner, the weight average molecular weight (Mw) / number average molecular weight (Mn) (hereinafter sometimes simply referred to as Mw / Mn) is 7.5 or less. preferable.
In the present invention, it is important that Mw / Mn is 7.5 or less from the viewpoint of achieving both low-temperature fixability and heat-resistant storage stability. The molecular weight distribution by GPC of the toner extract means the molecular weight distribution of the binder resin, and has a heat melting characteristic that shows a sharp viscosity drop (sharp melt property) near the fixing start temperature by narrowing the distribution. Therefore, it is possible to design a toner having both good heat storage stability and low-temperature fixability. When Mw / Mn exceeds 7.5, low-temperature fixability is inhibited.

  In the viscoelastic properties of the toner, the value of the ratio tan δ (G ″ / G ′) between the storage elastic modulus G ′ (Pa) and the loss viscosity G ″ (Pa) is 120 ° C. or higher and 160 ° C. or lower. In the temperature region, it is preferably 0.40 or more and 1.00 or less, and more preferably 0.50 or more and 0.90 or less. When the value of tan δ is 0.40 or more, it is preferable because the glossiness of the fixed image becomes good, and when it is 1.00 or less, the occurrence of uneven gloss can be suppressed.

  The gloss unevenness is an image abnormality in which the gloss on the fixed image is not uniform and partially increases or decreases. This is particularly important in the field of product printing where high-quality and high-gloss images are required. There are various generation mechanisms. As an example, there is a case where the history of the immediately preceding image pattern appears as uneven gloss on the immediately following image due to adhesion and accumulation of the release agent on the fixing member. FIG. 7 shows an image chart in the case where the first image has an image portion and a non-image portion in the immediately preceding image, and the entire solid image comes in the immediately following second image chart. Since the release agent adheres to the fixing member in the image portion of the immediately preceding image, and no release agent adheres to the non-image portion, the history of the immediately preceding image pattern remains as the adhesion of the release agent on the fixing member. At the time of fixing all solid images immediately after, due to this history, there is a difference in the amount of release agent on the image. (Evaluation site | part 2) A part with few releasability is a normal grade, and in some cases it becomes inadequate and it becomes comparatively low glossiness (evaluation site | part 1), and a glossiness difference generate | occur | produces.

  The tan δ of the toner can be measured using a dynamic viscoelasticity measuring device (for example, ARES (manufactured by TA Instruments)). That is, the sample was formed into a pellet having a diameter of 8 mm and a thickness of 1 to 2 mm, fixed to a parallel plate having a diameter of 8 mm, stabilized at 40 ° C., a frequency of 1 Hz (6.28 rad / s), and a strain amount of 0.1. % (Strain amount control mode) was measured by increasing the temperature up to 200 ° C. at a rate of temperature increase of 2.0 ° C./min.

  As a method for controlling the tan δ of the toner, a method similar to the method for controlling the gel content, a method for adjusting the compatibility between the low molecular weight body and the high molecular weight body of the binder resin, the core-shell type toner Although the method etc. which adjust compatibility of a core part and a shell part are mentioned, in this invention, it does not specifically limit.

  The toner of the present invention preferably has an acid value AV of 5 to 20 KOHmg / g and a hydroxyl value of 20 KOHmg / g or less. When the acid value AV is less than 5 KOH mg / g, it means that the polarity of the toner is lowered, and there is a concern that the affinity for paper is lowered and the effect of low-temperature fixability is weakened. Further, since the polarity is low, for example, when toner is prepared by water-based granulation, the wettability with water is too low, and the granulation property may be deteriorated. When the acid value AV is larger than 20 KOHmg / g, because of high polarity, it becomes weak against humidity and sufficient storage stability and charge stability may not be obtained under high temperature and high humidity. When the hydroxyl value OHV is larger than 20 KOHmg / g, the thermal characteristics may be lowered due to the influence of moisture due to the high temperature and high humidity environment, and the heat resistant storage stability may be deteriorated.

The gel amount of the present invention refers to an ethyl acetate insoluble component in Soxhlet extraction using ethyl acetate. The ethyl acetate insoluble component can be controlled by the weight average molecular weight Mw of the binder resin and the degree of cross-linking, and the method for controlling the increase or decrease in the gel amount is to prepare an amount of Mw and a resin containing a high degree of cross-linking contained in the toner. A method of increasing the Mw and the degree of cross-linking by reacting a resin in the toner is conceivable. However, the present invention is not limited thereto.
The ethyl acetate insoluble component obtained by Soxhlet extraction with ethyl acetate of the toner of the present invention is preferably in the range of 10% by mass to 30% by mass, and more preferably in the range of 12% by mass to 23% by mass. . When the ethyl acetate insoluble component is within the above range, it is possible to suppress deterioration of separation stability due to excessive decrease in viscosity while maintaining low viscosity effective for low temperature fixability and high gloss. From this, it is possible to design a toner having good low-temperature fixability, gloss properties, and separation stability.

  An example of Soxhlet extraction of toner with ethyl acetate will be described. A general Soxhlet extraction apparatus can be used for Soxhlet extraction. In a soxhlet extraction cylindrical filter paper, the weight of which has been accurately measured, 0.5 g of toner is precisely weighed, 200 g of ethyl acetate is placed in a flat bottom flask (300 ml), and the cylindrical filter paper is mounted in a soxhlet extraction tube. A flat bottom flask, a Soxhlet extraction tube, and a cooling tube are connected, the flat bottom flask is heated with a mantle heater, and the extraction operation is performed for 10 hours after the ethyl acetate in the flask starts to boil. The cylindrical filter paper after extraction is thoroughly washed with ethyl acetate, and then ethyl acetate as a solvent is sufficiently dried. The content of the ethyl acetate insoluble component contained in the toner is calculated from the sample weight measured first, the weight of the cylindrical filter paper, and the amount of extraction residue after extraction and drying. The temperature and time are not particularly limited, and can be changed as appropriate.

  Next, the 1/2 method softening point (T1 / 2) of the toner will be described. From the viewpoint of granulation properties (particle size distribution control, particle shape control, etc.), when the toner is produced by the ester elongation method described later, in order to achieve both toner separation stability and high gloss, It is important that the two-method softening point (T1 / 2) is within an appropriate range. In the present invention, when obtained by an ester elongation method, the 1/2 method softening point (T1 / 2) in a flow curve measured using an elevated flow tester of the toner is preferably 110 ° C. or higher and 135 ° C. or lower. .

  In the molecular weight distribution measured by GPC of the hexafluoroisopropanol (HFIP) soluble component of the toner, which is a feature of the present invention, the peak top molecular weight of the main peak (P0) is in the range of 3,000 to 10,000. When the peak top (P1) of an arbitrary peak having a molecular weight in the range of 250 to 2,500 is selected, the maximum and minimum peak intensities in the range of the molecular weight ± 100 of the peak top (P1) When the difference was 30 or less and the ester elongation method was used, it was found that the range in which both the toner separation stability and high gloss can be achieved is different from the conventional one.

  In the ester elongation method, the main factor governing the melting characteristics of the toner is considered to be the degree of elongation reaction of the prepolymer. The content of the molecular weight component is greatly different from the conventional one and has been reduced. This is due to the progress of the prepolymer extension reaction and the resulting extended product characteristics being different from the conventional ones. Inferred.

  The half-method softening point (T1 / 2) of the toner is preferably 110 ° C. or higher and 135 ° C. or lower, and more preferably 115 to 125 ° C. When the half-method softening point (T1 / 2) of the toner is 110 ° C. or higher, it is preferable because the separation resistance of the toner can be controlled to an appropriate value and good separation stability can be maintained. When the temperature is 135 ° C. or lower, the glossiness of the toner can be maintained at a required level or higher. This is preferable. By setting the temperature within this range, both separation stability and high gloss can be achieved.

  As a method for controlling the 1/2 method softening point (T1 / 2) of the toner, for example, a binder resin precursor (reactive group-containing prepolymer) having a functional group capable of reacting with an active hydrogen group is used. Examples thereof include a method for adjusting the molecular weight and content, a method for adjusting the temperature and time when the active hydrogen group-containing compound and the reactive group-containing prepolymer are allowed to react and extend in the toner production process. It is done.

The 1/2 method softening point (T1 / 2) of the toner can be measured by an appropriately selected method. For example, it can be obtained from a flow curve measured using an elevated flow tester CFT500 type (manufactured by Shimadzu Corporation). Can do. An example of the flow curve is shown in FIGS. In FIG. 1, Ts indicates the softening temperature, Tfb indicates the outflow start temperature, and the melting temperature in the 1/2 method is the T1 / 2 temperature.
An example of measurement conditions is shown below.

[Measurement condition]
Load: 10kg / cm ²
Temperature increase rate: 3.0 ° C / min
Die diameter: 0.50mm
Die length: 1.0mm
Measurement temperature: 40 ° C to 200 ° C

  The shape, size, etc. of the toner are not particularly limited and may be appropriately selected depending on the intended purpose. The average circularity, volume average particle size, volume average particle size and number average are as follows: It is preferable to have a ratio to the particle size (volume average particle size / number average particle size).

  The average circularity is a value obtained by dividing the circumference of an equivalent circle having the same projected shape as the shape of the toner by the circumference of the actual particles. For example, 0.950 to 0.980 is preferable, and 0.960 to 0 is preferable. .975 is more preferred. In addition, it is preferable that the particles having an average circularity of less than 0.95 are 15% or less.

  If the average circularity is less than 0.950, a satisfactory transferability and a high-quality image free from dust may not be obtained. On the other hand, if it exceeds 0.980, in an image forming system that employs blade cleaning or the like, a cleaning failure occurs on the photosensitive member and the transfer belt, and stains on the image, for example, an image area ratio such as a photographic image In the case of high image formation, the toner on which an untransferred image has been formed due to poor paper feeding or the like may become background smudges on the image accumulated as transfer residual toner on the photoreceptor. Alternatively, the charging roller that contacts and charges the photosensitive member may be contaminated, and the original charging ability may not be exhibited.

  The average circularity is measured using a flow type particle image analyzer (“FPIA-2100”, manufactured by Sysmex Corporation) and analyzed using analysis software (FPIA-2100 Data Processing Program for FPIA version 00-10). be able to.

  As a specific example, 0.1 to 0.5 ml of 10% by weight surfactant (alkylbenzene sulfonate, Neogen SC-A, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) was added to a glass 100 ml beaker, Add 1-0.5 g and stir with microspatel, then add 80 mL of ion exchanged water. The obtained dispersion is subjected to a dispersion treatment for 3 minutes with an ultrasonic disperser (manufactured by Honda Electronics Co., Ltd.). The shape and distribution of the toner are measured with the FPIA-2100 until the concentration of the dispersion reaches 5,000 to 15,000 / μL.

  In this measurement method, it is important that the concentration of the dispersion is 5,000 to 15,000 / μL from the viewpoint of measurement reproducibility of average circularity. In order to obtain the concentration of the dispersion, it is necessary to change the conditions of the dispersion, that is, the amount of surfactant to be added and the amount of toner. The amount of the surfactant varies depending on the hydrophobicity of the toner as in the measurement of the toner particle diameter described above. If it is added in a large amount, noise due to bubbles is generated, and if it is too small, the toner cannot be sufficiently wetted. It will be enough. The amount of toner added varies depending on the particle size, and is small when the particle size is small, and needs to be increased when the particle size is large. When the toner particle size is 3 μm to 10 μm, the toner amount is 0.1 g to 0.00 g. By adding 5 g, the dispersion concentration can be adjusted to 5,000 / μl to 15,000 / μl.

  There is no restriction | limiting in particular as a volume average particle diameter of the said toner, Although it can select suitably according to the objective, For example, 3 micrometers-10 micrometers are preferable, and 4 micrometers-7 micrometers are more preferable. When the volume average particle size is less than 3 μm, in the case of a two-component developer, the toner may be fused to the surface of the carrier during a long period of stirring in the developing device, and the charging ability of the carrier may be reduced. Therefore, it becomes difficult to obtain a high-resolution and high-quality image, and when the balance of the toner in the developer is performed, the variation in the toner particle size may increase.

The ratio of the volume average particle diameter to the number average particle diameter (volume average particle diameter / number average particle diameter) in the toner is preferably 1.00 to 1.25, and more preferably 1.00 to 1.15.
The volume average particle diameter and the ratio of the volume average particle diameter to the number average particle diameter (volume average particle diameter / number average particle diameter) are measured using a particle size measuring device (“Multisizer III”, manufactured by Beckman Coulter, Inc.). The measurement can be performed with an aperture diameter of 100 μm and the analysis can be performed with analysis software (Beckman Coulter Multisizer 3 Version 3.51).

  To give a specific example, 0.5 ml of 10% by weight surfactant (alkylbenzene sulfonate, Neogen SC-A, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) is added to a glass 100 ml beaker, and 0.5 g of each toner is added to make a micro. Stir with a spatula and then add 80 ml of ion-exchanged water. The obtained dispersion is subjected to a dispersion treatment for 10 minutes with an ultrasonic disperser (W-113MK-II, manufactured by Honda Electronics Co., Ltd.). The dispersion can be measured using the Multisizer III and Isoton III (manufactured by Beckman Coulter) as a measurement solution.

  In the measurement, the toner sample dispersion is dropped so that the concentration indicated by the apparatus is 8 ± 2%. In this measurement method, it is important that the concentration is 8 ± 2% from the viewpoint of the reproducibility of the particle size. Within this concentration range, no error occurs in the particle size.

<Toner raw material>
In the toner of the present invention, the toner base containing at least a binder resin and a release agent can contain other components as required, and an external additive is added as necessary.

<< Binder resin >>
There is no restriction | limiting in particular as said binder resin, According to the objective, it can select suitably. For example, polyester resin, silicone resin, styrene / acrylic resin, styrene resin, acrylic resin, epoxy resin, diene resin, phenol resin, terpene resin, coumarin resin, amidoimide resin, butyral resin, urethane resin, ethylene vinyl acetate resin, etc. Can be mentioned. These may be used individually by 1 type and may use 2 or more types together. Among these, polyester resins and resins obtained by combining polyester resins with the above other binder resins are preferable because they are excellent in low-temperature fixability and have sufficient flexibility even when the molecular weight is reduced.

-Polyester resin-
There is no restriction | limiting in particular as said polyester resin, Although it can select suitably according to the objective, An unmodified polyester resin and a modified polyester resin are preferable. These may be used individually by 1 type and may use 2 or more types together.

--Unmodified polyester resin--
There is no restriction | limiting in particular as said unmodified polyester resin, According to the objective, it can select suitably. Examples thereof include resins obtained by polyesterification of a polyol represented by the following general formula (1) and a polycarboxylic acid represented by the following general formula (2), a crystalline polyester resin, and the like.

However, in the said General formula (1), A represents the aromatic group or heterocyclic aromatic group which may have a C1-C20 alkyl group, an alkylene group, and a substituent, m is 2- Represents an integer of 4.
In the general formula (2), B represents an alkyl group having 1 to 20 carbon atoms, an alkylene group, an aromatic group that may have a substituent, or a heterocyclic aromatic group, and n represents 2 to 2 Represents an integer of 4.

  There is no restriction | limiting in particular as a polyol represented by the said General formula (1), According to the objective, it can select suitably. For example, ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, neopentyl glycol, 1,4-butenediol, 1,5-pentanediol, 1,6-hexanediol, 1,4-cyclohexanedimethanol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, sorbitol, 1,2,3,6-hexanetetrol, 1,4-sorbitan, Pentaerythritol, dipentaerythritol, tripentaerythritol, 1,2,4-butanetriol, 1,2,5-pentanetriol, glycerol, 2-methylpropanetriol, 2-methyl-1,2, -Butanetriol, trimethylolethane, trimethylolpropane, 1,3,5-trihydroxymethylbenzene, bisphenol A, bisphenol A ethylene oxide adduct, bisphenol A propylene oxide adduct, hydrogenated bisphenol A, hydrogenated bisphenol A oxidation Examples include ethylene adducts, hydrogenated bisphenol A propylene oxide adducts, and the like. These may be used alone or in combination of two or more.

  There is no restriction | limiting in particular as polycarboxylic acid represented by the said General formula (2), According to the objective, it can select suitably. For example, maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, phthalic acid, isophthalic acid, terephthalic acid, succinic acid, adipic acid, sebacic acid, azelaic acid, malonic acid, n-dodecenyl succinic acid, isooctyl succinic acid , Isododecenyl succinic acid, n-dodecyl succinic acid, isododecyl succinic acid, n-octenyl succinic acid, n-octyl succinic acid, isooctenyl succinic acid, isooctyl succinic acid, 1,2,4-benzenetricarboxylic acid, 2, , 5,7-Naphthalenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, 1,2,4-butanetricarboxylic acid, 1,2,5-hexanetricarboxylic acid, 1,3-dicarboxyl-2-methyl- 2-methylenecarboxypropane, 1,2,4-cyclohexanetricarboxylic acid, te La (methylenecarboxyl) methane, 1,2,7,8-octanetetracarboxylic acid, pyromellitic acid, empole trimer acid, etc., cyclohexanedicarboxylic acid, cyclohexenedicarboxylic acid, butanetetracarboxylic acid, diphenylsulfonetetracarboxylic acid, And ethylene glycol bis (trimellitic acid). These may be used alone or in combination of two or more.

--Modified polyester resin--
There is no restriction | limiting in particular as said modified polyester resin, According to the objective, it can select suitably. For example, an active hydrogen group-containing compound, a resin obtained by subjecting a polyester capable of reacting with the active hydrogen group-containing compound (hereinafter sometimes referred to as “polyester prepolymer”) to an extension reaction and / or a crosslinking reaction, etc. Can be mentioned. The extension reaction and / or the cross-linking reaction may be stopped by a reaction terminator (blocked monoamine such as diethylamine, dibutylamine, butylamine, laurylamine, ketimine compound, etc.) as necessary.

--- Active hydrogen group-containing compound ---
The active hydrogen group-containing compound acts as an elongation agent, a crosslinking agent or the like when the polyester prepolymer undergoes an elongation reaction, a crosslinking reaction, or the like in an aqueous phase.

  The active hydrogen group-containing compound is not particularly limited as long as it has an active hydrogen group, and can be appropriately selected according to the purpose. Especially, when the said polyester prepolymer is an isocyanate group containing polyester prepolymer mentioned later, amines are preferable at the point from which high molecular weight is attained.

  There is no restriction | limiting in particular as said active hydrogen group, According to the objective, it can select suitably. For example, a hydroxyl group (alcoholic hydroxyl group or phenolic hydroxyl group), an amino group, a carboxyl group, a mercapto group, etc. are mentioned. These may be contained singly or in combination of two or more.

  There is no restriction | limiting in particular as said amines which are the said active hydrogen group containing compound, According to the objective, it can select suitably. Examples thereof include diamine, trivalent or higher polyamine, amino alcohol, amino mercaptan, amino acid, and those obtained by blocking the amino group of these amines.

Examples of the diamine include aromatic diamines (phenylenediamine, diethyltoluenediamine, 4,4′diaminodiphenylmethane, etc.); alicyclic diamines (4,4′-diamino-3,3′dimethyldicyclohexylmethane, diaminecyclohexane, Isophorone diamine, etc.); aliphatic diamines (ethylene diamine, tetramethylene diamine, hexamethylene diamine, etc.) and the like.
Examples of the trivalent or higher polyamine include diethylenetriamine and triethylenetetramine.
Examples of the amino alcohol include ethanolamine and hydroxyethylaniline.
Examples of the amino mercaptan include aminoethyl mercaptan and aminopropyl mercaptan.
Examples of the amino acid include aminopropionic acid and aminocaproic acid.
Examples of the blocked amino groups of these amines include, for example, any of these amines (diamine, trivalent or higher polyamine, amino alcohol, amino mercaptan, amino acid, etc.) and ketones (acetone, methyl ethyl ketone, And ketimine compounds and oxazolyzone compounds obtained from methyl isobutyl ketone and the like.

  These may be used individually by 1 type and may use 2 or more types together. Among these, the amines are particularly preferably diamine and a mixture of a diamine and a small amount of a trivalent or higher polyamine.

--- Polymer capable of reacting with active hydrogen group-containing compound ---
The polymer that can react with the active hydrogen group-containing compound is not particularly limited as long as it is a polymer having at least a group that can react with the active hydrogen group-containing compound, and can be appropriately selected according to the purpose. Above all, it has excellent fluidity and transparency when melted, it is easy to adjust the molecular weight of the polymer component, and it is excellent in oil-less low-temperature fixability and releasability in dry toners. Is preferred, and an isocyanate group-containing polyester prepolymer is more preferred.

  There is no restriction | limiting in particular as said isocyanate group containing polyester prepolymer, According to the objective, it can select suitably. Examples thereof include polycondensates of polyols and polycarboxylic acids, and those obtained by reacting active hydrogen group-containing polyester resins with polyisocyanates.

  There is no restriction | limiting in particular as said polyol, According to the objective, it can select suitably. For example, alkylene glycol (ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,6-hexanediol, etc.), alkylene ether glycol (diethylene glycol, triethylene glycol, dipropylene) Glycol, polyethylene glycol, polypropylene glycol, polytetramethylene ether glycol, etc.), alicyclic diols (1,4-cyclohexanedimethanol, hydrogenated bisphenol A, etc.), bisphenols (bisphenol A, bisphenol F, bisphenol S, etc.), Alkylene oxide (ethylene oxide, propylene oxide, butylene oxide, etc.) adduct of the alicyclic diol, alkylene oxide of the bisphenol Diols such as adducts (ethylene oxide, propylene oxide, butylene oxide, etc.); polyhydric aliphatic alcohols (glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, sorbitol, etc.), trivalent or higher phenols (phenol novolac) , Cresol novolac, etc.) trihydric or higher polyols such as alkylene oxide adducts of trihydric or higher polyphenols; mixtures of diols and trihydric or higher polyols.

  These may be used individually by 1 type and may use 2 or more types together. Among these, the polyol is preferably the diol alone or a mixture of the diol and a small amount of the trivalent or higher polyol.

  Examples of the diol include alkylene glycols having 2 to 12 carbon atoms, alkylene oxide adducts of bisphenols (bisphenol A ethylene oxide 2 mol adduct, bisphenol A ethylene oxide 3 mol adduct, bisphenol A propylene oxide 2 mol adduct, bisphenol. A propylene oxide 3 mol adduct etc.) is preferred as the main component. In addition, alkylene glycol (ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, etc.) may be used for the purpose of adjusting the molecular weight and the mobility of the molecular weight.

  There is no restriction | limiting in particular as content in the isocyanate group containing polyester prepolymer of the said polyol, According to the objective, it can select suitably. For example, 0.5 mass%-40 mass% are preferable, 1 mass%-30 mass% are more preferable, and 2 mass%-20 mass% are especially preferable. When the content is less than 0.5% by mass, the hot offset resistance is deteriorated, and it may be difficult to achieve both the storage stability of the toner and the low-temperature fixability. Fixability may deteriorate.

  There is no restriction | limiting in particular as said polycarboxylic acid, According to the objective, it can select suitably. For example, alkylene dicarboxylic acid (succinic acid, adipic acid, sebacic acid, etc.); alkenylene dicarboxylic acid (maleic acid, fumaric acid, etc.); aromatic dicarboxylic acid (terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid, etc.); Examples thereof include polycarboxylic acids (such as aromatic polycarboxylic acids having 9 to 20 carbon atoms such as trimellitic acid and pyromellitic acid). These may be used individually by 1 type and may use 2 or more types together.

  Among these, the polycarboxylic acid is preferably an alkenylene dicarboxylic acid having 4 to 20 carbon atoms and an aromatic dicarboxylic acid having 8 to 20 carbon atoms. In place of the polycarboxylic acid, an anhydride of polycarboxylic acid, a lower alkyl ester (methyl ester, ethyl ester, isopropyl ester, etc.) may be used.

  There is no restriction | limiting in particular as a mixing ratio of the said polyol and the said polycarboxylic acid, According to the objective, it can select suitably. The equivalent ratio [OH] / [COOH] of the hydroxyl group [OH] of the polyol and the carboxyl group [COOH] of the polycarboxylic acid is preferably 2/1 to 1/1, and 1.5 / 1 to 1/1. Is more preferable, and 1.3 / 1 to 1.02 / 1 is particularly preferable.

  There is no restriction | limiting in particular as said polyisocyanate, According to the objective, it can select suitably. For example, aliphatic polyisocyanates (tetramethylene diisocyanate, hexamethylene diisocyanate, 2,6-diisocyanatomethylcaproate, octamethylene diisocyanate, decamethylene diisocyanate, dodecamethylene diisocyanate, tetradecamethylene diisocyanate, trimethylhexane diisocyanate, tetramethylhexane Diisocyanates, etc.); cycloaliphatic polyisocyanates (isophorone diisocyanate, cyclohexylmethane diisocyanate, etc.); aromatic diisocyanates (tolylene diisocyanate, diphenylmethane diisocyanate, 1,5-naphthylene diisocyanate, diphenylene-4,4′-diisocyanate, 4,4 '-Diisocyanato-3,3'-dimethyldiphenyl, 3-methyl Diphenylmethane-4,4′-diisocyanate, diphenyl ether-4,4′-diisocyanate, etc.); araliphatic diisocyanate (α, α, α ′, α′-tetramethylxylylene diisocyanate, etc.); isocyanurates (Tris-isocyanate) Natoalkyl-isocyanurate, triisocyanatocycloalkyl-isocyanurate, etc.); these phenol derivatives; those blocked with oxime, caprolactam and the like. These may be used alone or in combination of two or more.

  There is no restriction | limiting in particular as a mixing ratio of the said polyisocyanate and the said active hydrogen group containing polyester resin (hydroxyl group containing polyester resin), According to the objective, it can select suitably. The equivalent ratio [NCO] / [OH] of the isocyanate group [NCO] of the polyisocyanate and the hydroxyl group [OH] of the hydroxyl group-containing polyester resin is preferably 5/1 to 1/1, and 4/1 to 1.2. / 1 is more preferable, and 3/1 to 1.5 / 1 is particularly preferable. When the equivalent ratio [NCO] / [OH] is less than 1/1, the offset resistance may be deteriorated, and when it exceeds 5/1, the low-temperature fixability may be deteriorated.

  There is no restriction | limiting in particular as content of the said polyisocyanate in the said isocyanate group containing polyester prepolymer, According to the objective, it can select suitably. 0.5 mass%-40 mass% are preferable, 1 mass%-30 mass% are more preferable, 2 mass%-20 mass% are especially preferable. When the content is less than 0.5% by mass, the hot offset resistance is deteriorated, and it may be difficult to achieve both storage stability and low-temperature fixability. May get worse.

  The average number of isocyanate groups contained in one molecule of the isocyanate group-containing polyester prepolymer is preferably 1 or more, more preferably 1.2 to 5, and more preferably 1.5 to 4. When the average number is less than 1, the molecular weight of the polyester resin (RMPE) modified with a urea bond-forming group is lowered, and the hot offset resistance may be deteriorated.

  There is no restriction | limiting in particular as a mixing ratio of the said isocyanate group containing polyester prepolymer and the said amines, According to the objective, it can select suitably. The mixing equivalent ratio [NCO] / [NHx] of the isocyanate group [NCO] in the isocyanate group-containing polyester prepolymer and the amino group [NHx] in the amines is preferably 1/3 to 3/1. / 2 to 2/1 is more preferable, and 1 / 1.5 to 1.5 / 1 is particularly preferable. If the mixing equivalent ratio ([NCO] / [NHx]) is less than 1/3, the low-temperature fixability may be reduced. If it exceeds 3/1, the molecular weight of the urea-modified polyester resin is reduced. Hot offset resistance may deteriorate.

--- Method for synthesizing polymer capable of reacting with active hydrogen group-containing compound ---
There is no restriction | limiting in particular as a synthesis method of the polymer which can react with the said active hydrogen group containing compound, According to the objective, it can select suitably. For example, in the case of the isocyanate group-containing polyester prepolymer, the polyol and the polycarboxylic acid are heated to 150 ° C. to 280 ° C. in the presence of a known esterification catalyst (titanium tetrabutoxide, dibutyltin oxide, etc.). And a method of synthesizing by reacting the polyisocyanate with the hydroxyl group-containing polyester at 40 ° C. to 140 ° C. after the water is distilled off to obtain the hydroxyl group-containing polyester. .

  There is no restriction | limiting in particular as a weight average molecular weight (Mw) of the polymer which can react with the said active hydrogen group containing compound, According to the objective, it can select suitably. The molecular weight distribution by GPC (gel permeation chromatography) of the soluble portion of tetrahydrofuran (THF) is preferably 3,000 to 40,000, more preferably 4,000 to 30,000. When the weight average molecular weight (Mw) is less than 3,000, the storage stability may be deteriorated, and when it exceeds 40,000, the low temperature fixability may be deteriorated.

  The weight average molecular weight (Mw) can be measured, for example, as follows. First, the column was stabilized in a 40 ° C. heat chamber, and at this temperature, tetrahydrofuran (THF) as a column solvent was flowed at a flow rate of 1 mL / min, and the sample concentration was adjusted to 0.05 to 0.6% by mass. Measurement is performed by injecting 50 μL to 200 μL of a tetrahydrofuran sample solution. In measuring the molecular weight of the sample, the molecular weight distribution of the sample is calculated from the relationship between the logarithmic value of the calibration curve prepared by several monodisperse polystyrene standard samples and the number of counts.

As a standard polystyrene sample for preparing a calibration curve, Pressure Chemical Co. Or the molecular weight made by Toyo Soda Industry Co., Ltd. is 6 × 10, 2.1 × 10 ² , 4 × 10 ² , 1.75 × 10 ⁴ , 1.1 × 10 ⁵ , 3.9 × 10 ⁵ , 8.6 × It is preferable to use 10 ⁵ , 2 × 10 ⁶ , and 4.48 × 10 ⁶ , and use at least about 10 standard polystyrene samples. An RI (refractive index) detector can be used as the detector.

<< Releasing agent >>
There is no restriction | limiting in particular as said mold release agent, According to the objective, it can select suitably. For example, plant wax (carnauba wax, cotton wax, wood wax, rice wax, etc.), animal wax (beeswax, lanolin, etc.), mineral wax (ozokerite, cercin etc.), petroleum wax (paraffin, microcrystalline, petrolatum, etc.) ) Waxes and waxes; synthetic hydrocarbon waxes (Fischer-Tropsch wax, polyethylene wax, etc.), synthetic waxes other than natural waxes (esters, ketones, ethers, etc.); 1,2-hydroxystearic acid amide, Fatty acid amides such as stearic acid amide, phthalic anhydride imide, chlorinated hydrocarbons; homopolymers or copolymers of polyacrylates such as poly (n-stearyl methacrylate) and poly (n-lauryl methacrylate) which are low molecular weight crystalline polymers ( Acrylic acid n- Crystalline polymer having a stearyl over long chain alkyl group in the side chain of ethyl methacrylate copolymer, etc.) and the like; and the like.

  Among these, Fischer-Tropsch wax, paraffin wax, microcrystalline wax, monoester wax, and rice wax are preferable because less unnecessary volatile organic compounds are generated during fixing.

  A commercial item can be used for the mold release agent. Examples of the microcrystalline wax include “HI-MIC-1045”, “HI-MIC-1070”, “HI-MIC-1080”, “HI-MIC-1090” manufactured by Nippon Seiki Co., Ltd. “Bsquare 180 White”, “Bsquare 195” manufactured by WAX Petrolife, “CAREVALAC WN-1442” manufactured by Cray Valley, and the like.

  There is no restriction | limiting in particular as melting | fusing point of the said mold release agent, Although it can select suitably according to the objective, 60 to 100 degreeC is preferable and 65 to 90 degreeC is more preferable. When the melting point is 60 ° C. or more, even when stored at a high temperature of about 30 to 50 ° C., it is possible to suppress the exudation of the release agent from the toner base material and maintain good heat-resistant storage stability. When the temperature is 100 ° C. or lower, it is preferable because cold offset hardly occurs during fixing at a low temperature.

The melting point is measured by DSC. For example, it can be measured under the following measurement conditions using TA-60WS and DSC-60 manufactured by Shimadzu Corporation.
(Measurement condition)
Sample container: Aluminum sample pan (with lid)
Sample amount: 5mg
Reference: Aluminum sample pan (alumina 10mg)
Atmosphere: Nitrogen (flow rate 50 mL / min)
Temperature conditions 1st. Temperature rise Start temperature: 20 ° C., Temperature rise rate: 10 ° C./min, End temperature: 150 ° C., Holding time: None 1st. Temperature drop Temperature drop: 10 ° C./min, end temperature: 20 ° C., retention time: none 2nd. Temperature rise Temperature rise rate: 10 ° C / min, end temperature: 150 ° C
The measurement results are analyzed using data analysis software (TA-60, version 1.52) manufactured by Shimadzu Corporation.
The melting point is 2nd. The temperature at the top of the endothermic peak measured at elevated temperature is used.

  The release agent is preferably present in a dispersed state in the toner base particles, and for this purpose, the release agent and the binder resin are preferably incompatible with each other. The method for finely dispersing the release agent in the toner base particles is not particularly limited and may be appropriately selected depending on the purpose. For example, the release agent is dispersed by applying a kneading shear force during toner production. The method etc. are mentioned.

  The dispersion state of the release agent can be confirmed by observing a thin film slice of toner particles with a transmission electron microscope (TEM). The dispersion diameter of the release agent is preferably small, but if it is too small, there are cases where bleeding during fixing is insufficient. Therefore, if the release agent can be confirmed at a magnification of 10,000, the release agent is present in a dispersed state. When the release agent cannot be confirmed at 10,000 times, even when finely dispersed, the dyeing at the time of fixing becomes insufficient.

  There is no restriction | limiting in particular as content in the said toner of the said mold release agent, Although it can select suitably according to the objective, 3 mass%-15 mass% are preferable, and 5 mass%-10 mass% are more preferable. . When the content is less than 3% by mass, the hot offset resistance may be deteriorated, which is not preferable. When the content exceeds 15% by mass, the exudation amount of the release agent during fixing tends to be excessive. This is not preferable because the heat-resistant storage stability tends to deteriorate.

<< Other ingredients >>
-Colorant-
There is no restriction | limiting in particular as a coloring agent used for the said toner, According to the objective, it can select suitably from a well-known coloring agent.

  There is no restriction | limiting in particular as a color of the colorant of the said toner, According to the objective, it can select suitably. The toner can be at least one selected from black toner, cyan toner, magenta toner, and yellow toner, and each color toner can be obtained by appropriately selecting the type of colorant. preferable.

  Examples of black products include carbon blacks (CI pigment black 7) such as furnace black, lamp black, acetylene black, channel black, copper, iron (CI pigment black 11), titanium oxide, and the like. And organic pigments such as aniline black (CI Pigment Black 1).

  Examples of the magenta color pigment include C.I. I. Pigment Red 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 21, 22, 23, 30, 31, 32, 37, 38, 39, 40, 41, 48, 48: 1, 49, 50, 51, 52, 53, 53: 1, 54, 55, 57, 57: 1, 58, 60, 63, 64, 68, 81, 83, 87, 88, 89, 90, 112, 114, 122, 123, 150, 163, 177, 179, 184, 202, 206, 207, 209, 211, 269; I. Pigment violet 19; C.I. I. Bat red 1, 2, 10, 13, 15, 23, 29, 35, etc. are mentioned.

  Examples of the color pigment for cyan include C.I. I. Pigment Blue 2, 3, 15, 15: 1, 15: 2, 15: 3, 15: 4, 15: 6, 16, 17, 60; I. Bat Blue 6; C.I. I. Acid Blue 45 and copper phthalocyanine pigments having 1 to 5 phthalimidomethyl groups substituted on the phthalocyanine skeleton, Green 7, Green 36, and the like.

  Examples of the color pigment for yellow include C.I. I. Pigment Yellow 1, 2, 3, 4, 5, 6, 7, 10, 11, 12, 13, 14, 15, 16, 17, 23, 55, 65, 73, 74, 83, 97, 110, 139, 151, 154, 155, 180, 185; I. Bat yellow 1, 3, 20, orange 36 and the like.

  The content of the colorant in the toner is preferably 1% by mass to 15% by mass, and more preferably 3% by mass to 10% by mass. When the content is less than 1% by mass, the coloring power of the toner may be reduced. When the content is more than 15% by mass, poor dispersion of the pigment in the toner may occur. The characteristics may be degraded.

  The colorant may be used as a master batch combined with a resin. Such a resin is not particularly limited, but it is preferable to use a binder resin or a resin having a structure similar to the binder resin from the viewpoint of compatibility with the binder resin.

  The masterbatch can be produced by applying a high shear force and mixing or kneading the resin and the colorant. At this time, it is preferable to add an organic solvent in order to enhance the interaction between the colorant and the resin. Also, the so-called flushing method is preferable in that the wet cake of the colorant can be used as it is, and there is no need to dry it. The flushing method is a method in which an aqueous paste containing water of a colorant is mixed or kneaded together with a resin and an organic solvent, and the colorant is transferred to the resin side to remove water and the organic solvent. For mixing or kneading, for example, a high shear dispersion device such as a three-roll mill can be used.

-Charge control agent-
Further, in order to impart an appropriate charging ability to the toner, a charge control agent can be contained in the toner as necessary.
Any known charge control agent can be used as the charge control agent. Since the color tone may change when a colored material is used, a colorless or nearly white material is preferable. For example, a triphenylmethane dye, a molybdate chelate pigment, a rhodamine dye, an alkoxyamine, a quaternary ammonium salt (fluorine) Modified quaternary ammonium salts), alkylamides, phosphorus alone or compounds thereof, tungsten alone or compounds thereof, fluorine-based activators, metal salts of salicylic acid, metal salts of salicylic acid derivatives, and the like. These may be used individually by 1 type and may use 2 or more types together.

  The content of the charge control agent is determined by the toner production method including the type of the binder resin and the dispersion method, and is not uniquely limited. 01 mass%-5 mass% are preferable, and 0.02 mass%-2 mass% are more preferable. When the addition amount exceeds 5% by mass, the chargeability of the toner is too high, the effect of the charge control agent is reduced, the electrostatic attraction with the developing roller is increased, the developer fluidity is reduced, and the image The density may be lowered, and if it is less than 0.01% by mass, the charge start-up property and the charge amount are not sufficient, and the toner image may be easily affected.

<< External additive >>
There is no restriction | limiting in particular as said external additive, According to the objective, it can select suitably from well-known things. For example, silica fine particles, hydrophobized silica fine particles, fatty acid metal salts (eg, zinc stearate, aluminum stearate, etc.); metal oxides (eg, titania, alumina, tin oxide, antimony oxide, etc.) or their hydrophobized products, fluoro Examples thereof include polymers. Among these, hydrophobized silica fine particles, titania particles, and hydrophobized titania fine particles are preferable.

  Examples of the hydrophobized silica fine particles include HDK H2000T, HDK H2000 / 4, HDK H2050EP, HVK21, HDK H1303VP (all manufactured by Clariant Japan); R972, R974, RX200, RY200, R202, R805, R812, NX90G (all manufactured by Nippon Aerosil Co., Ltd.) and the like.

  Examples of the titania fine particles include P-25 (manufactured by Nippon Aerosil Co., Ltd.); STT-30, STT-65C-S (both manufactured by Titanium Industry Co., Ltd.); TAF-140 (manufactured by Fuji Titanium Industry Co., Ltd.); MT-150W. , MT-500B, MT-600B, MT-150A (all of which are manufactured by Teica).

  Examples of the hydrophobized titanium oxide fine particles include T-805 (manufactured by Nippon Aerosil Co., Ltd.); STT-30A, STT-65S-S (both manufactured by Titanium Industry Co., Ltd.); TAF-500T, TAF-1500T (any Also, manufactured by Fuji Titanium Industry Co., Ltd.); MT-100S, MT-100T (both manufactured by Teika); IT-S (produced by Ishihara Sangyo Co., Ltd.).

  There is no restriction | limiting in particular as content of the said external additive, Although it can select suitably according to the objective, 0.3 mass part-3.0 mass parts are preferable with respect to 100 mass parts of toner base particles. 0.5 parts by mass to 2.0 parts by mass is more preferable.

  The total coverage of the external additive with respect to the toner base particles is not particularly limited, but is preferably 50% to 90%, and more preferably 60% to 80%.

<Toner production method>
The toner production method and materials in the present invention can be any known ones as long as they satisfy the conditions, and are not particularly limited. For example, the toner particles may be mixed in a kneading and pulverization method or an aqueous medium. There is a so-called chemical method of granulating.

Examples of the chemical method include a suspension polymerization method, an emulsion polymerization method, a seed polymerization method, a dispersion polymerization method, etc., in which a monomer is used as a starting material; a resin or a resin precursor is dissolved in an organic solvent and the like in an aqueous medium. Dispersing or emulsifying dissolution suspension method; in the dissolution suspension method, an oil phase composition containing a resin precursor (reactive group-containing prepolymer) having a functional group capable of reacting with an active hydrogen group is contained in resin fine particles. A method of emulsifying or dispersing in an aqueous medium and reacting an active hydrogen group-containing compound and the reactive group-containing prepolymer in the aqueous medium (ester elongation method); from a resin or resin precursor and an appropriate emulsifier Phase inversion emulsification method in which water is added to the resulting solution for phase inversion; aggregation in which resin particles obtained by these methods are dispersed in an aqueous medium and granulated into particles of a desired size by heating and melting And the like. Among these, the toner obtained by the dissolution suspension method, the ester elongation method, and the aggregation method is preferable from the viewpoint of granulation properties (particle size distribution control, particle shape control, etc.), and the toner obtained by the ester elongation method is preferable. More preferred.
In the following, a detailed description of these production methods will be given.

  The kneading and pulverizing method is, for example, a method of producing the toner base particles by pulverizing and classifying a toner material having at least a colorant, a binder resin, and a release agent melted and kneaded.

  In the melt kneading, the toner materials are mixed, and the mixture is charged into a melt kneader and melt kneaded. As the melt kneader, for example, a uniaxial or biaxial continuous kneader or a batch kneader using a roll mill can be used. For example, a KTK type twin screw extruder manufactured by Kobe Steel, a TEM type extruder manufactured by Toshiba Machine Co., Ltd., a twin screw extruder manufactured by Casey Kay, a PCM type twin screw extruder manufactured by Ikegai Iron Works, and a Kneader manufactured by Buss Co., Ltd. are suitable. Used. This melt-kneading is preferably performed under appropriate conditions so as not to cause the molecular chains of the binder resin to be broken. Specifically, the melt-kneading temperature is determined with reference to the softening point of the binder resin. If the temperature is higher than the softening point, cutting is severe, and if the temperature is too low, dispersion may not proceed.

  In the pulverization, the kneaded product obtained by the kneading is pulverized. In this pulverization, it is preferable that the kneaded material is first coarsely pulverized and then finely pulverized. At this time, a method of pulverizing by colliding with a collision plate in a jet stream, pulverizing particles by colliding with each other in a jet stream, or pulverizing with a narrow gap between a mechanically rotating rotor and a stator is preferably used.

In the classification, the pulverized product obtained by the pulverization is classified and adjusted to particles having a predetermined particle diameter. The classification can be performed, for example, by removing the fine particle portion with a cyclone, a decanter, a centrifuge, or the like.
After the pulverization and classification are completed, the pulverized product is classified into an air stream by centrifugal force or the like, and toner base particles having a predetermined particle diameter can be produced.

  In the dissolution suspension method, for example, an oil phase composition in which a toner composition containing at least a binder resin or a resin precursor, a colorant, and a release agent is dissolved or dispersed in an organic solvent is used. This is a method for producing toner base particles by dispersing or emulsifying in a medium.

The organic solvent used for dissolving or dispersing the toner composition is preferably volatile with a boiling point of less than 100 ° C. from the viewpoint of easy removal of the solvent later.
Examples of the organic solvent include ester solvents such as ethyl acetate, butyl acetate, methoxybutyl acetate, methyl cellosolve acetate, ethyl cellosolve acetate, diethyl ether, tetrahydrofuran, dioxane, ethyl cellosolve, butyl cellosolve, and propylene glycol monomethyl. Ether solvents such as ether, ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, di-n-butyl ketone, cyclohexanone, methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, t-butanol, 2 -Alcohol solvents, such as ethyl hexyl alcohol and benzyl alcohol, and these 2 or more types of mixed solvents are mentioned.

In the dissolution suspension method, when the oil phase composition is dispersed or emulsified in an aqueous medium, an emulsifier or a dispersant may be used as necessary.
As the emulsifier or dispersant, known surfactants, water-soluble polymers and the like can be used. The surfactant is not particularly limited, and is an anionic surfactant (alkyl benzene sulfonic acid, phosphate ester, etc.), a cationic surfactant (quaternary ammonium salt type, amine salt type, etc.), an amphoteric surfactant (carbon carboxyl). Acid salt type, sulfate ester type, sulfonate salt type, phosphate ester salt type, etc.), nonionic surfactants (AO addition type, polyhydric alcohol type, etc.) and the like. One surfactant may be used alone, or two or more surfactants may be used in combination.

Examples of the water-soluble polymer include cellulose compounds (for example, methyl cellulose, ethyl cellulose, hydroxyethyl cellulose, ethyl hydroxyethyl cellulose, carboxymethyl cellulose, hydroxypropyl cellulose and saponified products thereof), gelatin, starch, dextrin, gum arabic, chitin, chitosan. , Polyvinyl alcohol, polyvinyl pyrrolidone, polyethylene glycol, polyethyleneimine, polyacrylamide, acrylic acid (salt) -containing polymer (sodium polyacrylate, potassium polyacrylate, ammonium polyacrylate, partially neutralized sodium hydroxide of polyacrylic acid) , Sodium acrylate-acrylic acid ester copolymer), sodium hydroxide of styrene-maleic anhydride copolymer ( Min) neutralized product water-soluble polyurethane (polyethylene glycol, reaction products of polycaprolactone diol with polyisocyanate and the like) and the like.
Moreover, said organic solvent, a plasticizer, etc. can also be used together as an auxiliary | assistant of emulsification or dispersion | distribution.

  The toner according to the present invention includes at least a binder resin, a binder resin precursor having a functional group capable of reacting with an active hydrogen group (reactive group-containing prepolymer), a colorant, and a release agent in a dissolution suspension method. An active phase group-containing prepolymer and an active hydrogen group-containing compound contained in the oil phase composition and / or the aqueous medium are dispersed or emulsified in an aqueous medium containing resin fine particles. It is preferable to obtain the toner base particles by a method of reacting with (the ester elongation method).

The resin fine particles can be formed using a known polymerization method, but is preferably obtained as an aqueous dispersion of resin fine particles. Examples of the method for preparing an aqueous dispersion of resin fine particles include the methods shown in the following (a) to (h).
(A) A method in which an aqueous dispersion of resin fine particles is directly prepared from a vinyl monomer as a starting material by any one of a suspension polymerization method, an emulsion polymerization method, a seed polymerization method and a dispersion polymerization method.
(B) After dispersing a precursor of polyaddition or condensation resin such as polyester resin, polyurethane resin, epoxy resin (monomer, oligomer, etc.) or a solvent solution thereof in an aqueous medium in an aqueous medium, A method of preparing an aqueous dispersion of resin fine particles by heating or adding a curing agent to cure.
(C) Polyaddition or condensation resin precursors (monomers, oligomers, etc.) such as polyester resins, polyurethane resins, and epoxy resins, or solvent solutions thereof (preferably liquids, which may be liquefied by heating). A method for preparing an aqueous dispersion of resin fine particles by dissolving a suitable emulsifier in the mixture and then adding water to effect phase inversion emulsification.
(D) A resin synthesized in advance by a polymerization reaction (for example, addition polymerization, ring-opening polymerization, polyaddition, addition condensation, condensation polymerization, etc.) is pulverized and classified using a mechanical rotary type or jet type fine pulverizer. A method of preparing an aqueous dispersion of resin fine particles by obtaining resin fine particles and then dispersing in water in the presence of an appropriate dispersant.
(E) Fine resin particles are formed by spraying a resin solution in which a resin synthesized in advance by a polymerization reaction (for example, addition polymerization, ring-opening polymerization, polyaddition, addition condensation, condensation polymerization, etc.) is dissolved in a solvent. Then, resin fine particles are dispersed in water in the presence of a suitable dispersant to prepare an aqueous dispersion of resin fine particles.
(F) A poor solvent is added to a resin solution prepared by previously dissolving a resin synthesized by a polymerization reaction (for example, addition polymerization, ring-opening polymerization, polyaddition, addition condensation, condensation polymerization, etc.) in a solvent, or heated to a solvent in advance. By cooling the dissolved resin solution, the resin fine particles are precipitated, the solvent is removed to form the resin fine particles, and then the resin fine particles are dispersed in water in the presence of an appropriate dispersant to disperse the resin fine particles in water. A method for preparing a liquid.
(G) A resin solution obtained by dissolving a resin previously synthesized by a polymerization reaction (for example, addition polymerization, ring-opening polymerization, polyaddition, addition condensation, condensation polymerization, etc.) in a solvent in the presence of an appropriate dispersant. A method of preparing an aqueous dispersion of resin fine particles by dispersing in a solvent and then removing the solvent by heating, decompression or the like.
(H) A suitable emulsifier is dissolved in a resin solution prepared by previously dissolving a resin synthesized by a polymerization reaction (for example, addition polymerization, ring-opening polymerization, polyaddition, addition condensation, condensation polymerization, etc.) in a solvent, and then water To prepare an aqueous dispersion of resin fine particles by phase inversion emulsification.

  The volume average particle diameter of the resin fine particles is preferably 10 nm or more and 300 nm or less, and more preferably 30 nm or more and 120 nm or less. When the volume average particle size of the resin fine particles is less than 10 nm or more than 300 nm, the particle size distribution of the toner may be deteriorated.

  The solid content concentration of the oil phase is preferably about 40 to 80%. If the concentration is too high, dissolution or dispersion becomes difficult, and the viscosity becomes high and difficult to handle. If the concentration is too low, the productivity of the toner decreases.

  The toner composition other than the binder resin such as the colorant and the release agent, and the masterbatch thereof are individually dissolved or dispersed in an organic solvent, and then mixed with the binder resin solution or dispersion. May be.

  As the aqueous medium, water alone may be used, but a solvent miscible with water may be used in combination. Examples of miscible solvents include alcohol (methanol, isopropanol, ethylene glycol, etc.), dimethylformamide, tetrahydrofuran, cellosolves (methyl cellosolve, etc.), lower ketones (acetone, methyl ethyl ketone, etc.) and the like.

  The dispersion or emulsification method in the aqueous medium is not particularly limited, and known equipment such as a low-speed shearing type, a high-speed shearing type, a friction type, a high-pressure jet type, and an ultrasonic wave can be applied. Among these, the high-speed shearing method is preferable from the viewpoint of reducing the particle size of the particles. When a high-speed shearing disperser is used, the rotational speed is not particularly limited, but is usually 1000 to 30000 rpm, preferably 5000 to 20000 rpm. The temperature during dispersion is usually 0 to 150 ° C. (under pressure), preferably 20 to 80 ° C.

  In order to remove the organic solvent from the obtained emulsified dispersion, there is no particular limitation, and a known method can be used. For example, the whole system is gradually raised while stirring the whole system under normal pressure or reduced pressure. A method of warming and completely evaporating and removing the organic solvent in the droplets can be employed.

  As a method of washing and drying the toner base particles dispersed in the aqueous medium, a known technique is used. That is, after solid-liquid separation with a centrifuge, a filter press, etc., the obtained toner cake is redispersed in ion-exchanged water at room temperature to about 40 ° C., and after pH adjustment with acid or alkali as necessary, After removing the impurities and surfactants by repeating the process of solid-liquid separation again and again, the toner powder is obtained by drying with an air dryer, circulating dryer, vacuum dryer, vibration fluid dryer, etc. . At this time, the fine particle component of the toner may be removed by centrifugation or the like, and a desired particle size distribution can be obtained using a known classifier after drying, if necessary.

  In the agglomeration method, for example, a toner base particle is produced by mixing and aggregating a resin fine particle dispersion comprising at least a binder resin, a colorant particle dispersion, and a release agent particle dispersion as necessary. is there. The resin fine particle dispersion is obtained by a known method such as emulsion polymerization, seed polymerization, phase inversion emulsification, and the like. The colorant particle dispersion and the release agent particle dispersion are obtained by a known wet dispersion method. It can be obtained by dispersing a colorant or a release agent in an aqueous medium.

For the control of the aggregation state, methods such as applying heat, adding a metal salt, and adjusting pH are preferably used.
There is no restriction | limiting in particular as said metal salt, The monovalent metal which comprises salts, such as sodium and potassium; The bivalent metal which comprises salts, such as calcium and magnesium; The trivalent metal which comprises salts, such as aluminum, etc. Is mentioned.
Examples of the anion constituting the salt include chloride ion, bromide ion, iodide ion, carbonate ion, and sulfate ion. Among these, magnesium chloride, aluminum chloride, and complexes and multimers thereof are preferable. .
Also, heating between the agglomeration and after completion of the agglomeration can promote fusion between the resin fine particles, which is preferable from the viewpoint of toner uniformity. Furthermore, the shape of the toner can be controlled by heating. Normally, the toner becomes more spherical when heated further.

  As the method for washing and drying the toner base particles dispersed in the aqueous medium, the above-described method and the like can be used.

Further, in order to improve the fluidity, storage stability, developability, and transferability of the toner, the coalesced particles are added to and mixed with the toner base particles produced as described above. Inorganic fine particles may be added and mixed.
For mixing the additives, a general powder mixer is used, but it is preferable to equip a jacket or the like to adjust the internal temperature. In order to change the load history applied to the additive, the additive may be added midway or gradually. In this case, you may change the rotation speed, rolling speed, time, temperature, etc. of a mixer. Alternatively, a strong load may be applied first, then a relatively weak load, or vice versa. Examples of the mixing equipment that can be used include a V-type mixer, a rocking mixer, a Ladige mixer, a Nauter mixer, and a Henschel mixer. Next, the toner is obtained by passing through a sieve of 250 mesh or more to remove coarse particles and aggregated particles.

(Developer)
The developer of the present invention contains at least the toner and contains other components such as a carrier selected as appropriate. The developer may be a one-component developer or a two-component developer. However, when it is used for a high-speed printer or the like corresponding to the recent improvement in information processing speed, the life is improved. In view of the above, the two-component developer is preferable.

  In the case of the one-component developer using the toner, toner aggregation does not easily occur over time against stress caused by the developing means, and toner filming on the developing roller as the developer carrying member In addition, there is no fusion of toner to a layer thickness regulating member such as a blade for thinning the toner, and good and stable image quality can be obtained by maintaining good image density stability and transferability. . In addition, in the case of the two-component developer using the toner, toner aggregation does not easily occur over time even with agitation stress caused by the developing means, and the occurrence of abnormal images is suppressed, and the image density is stable. Good and stable image quality can be obtained by maintaining good properties and transferability.

<Career>
There is no restriction | limiting in particular as said carrier, Although it can select suitably according to the objective, What has a core particle and the resin layer (coating layer) which coat | covers this core particle is preferable.

<< Core particle >>
The core particles are not particularly limited as long as they are magnetic core particles, and can be appropriately selected according to the purpose. For example, ferromagnetic metals such as iron and cobalt; oxidation of magnetite, hematite, ferrite, and the like Iron; resin particles in which magnetic materials such as various alloys and compounds are dispersed in a resin. Among these, Mn-based ferrite, Mn-Mg-based ferrite, Mn-Mg-Sr-based ferrite and the like are preferable from the viewpoint of environmental considerations.

-Weight average particle diameter Dw of core particles-
The weight average particle diameter Dw of the core particles refers to the particle diameter at an integrated value of 50% in the particle size distribution of the core particles obtained by a laser diffraction or scattering method. There is no restriction | limiting in particular as the weight average particle diameter Dw of the said core particle, Although it can select suitably according to the objective, 10 micrometers-80 micrometers are preferable, and 20 micrometers-65 micrometers are more preferable.

  The weight average particle diameter Dw of the core particles is measured by using a microtrac particle size distribution meter (HRA9320-X100, manufactured by Honeywell) as a particle diameter distribution (relationship between number frequency and particle diameter) of particles measured on a number basis. And measured under the conditions described below, and calculated using the following formula (I). Each channel represents a length for dividing the particle size range in the particle size distribution chart into measurement width units, and the lower limit value of the particle size stored in each channel is adopted as the representative particle size.

Dw = {1 / Σ (nD3)} × {Σ (nD4)} (I)
However, in said formula (I), D represents the representative particle size (micrometer) of the core particle which exists in each channel, and n represents the total number of the core particle which exists in each channel.

[Measurement condition]
[1] Particle size range: 100 μm to 8 μm
[2] Channel length (channel width): 2 μm
[3] Number of channels: 46
[4] Refractive index: 2.42

<< Coating layer >>
The coating layer contains at least a resin, and may contain other components such as a filler as necessary.

-Resin-
There is no restriction | limiting in particular as resin for forming the coating layer of a carrier, According to the objective, it can select suitably. For example, a crosslinkable copolymer containing polyolefin (for example, polyethylene, polypropylene, etc.) or a modified product thereof, polystyrene, acrylic resin, acrylonitrile, vinyl acetate, vinyl alcohol, vinyl chloride, vinyl carbazole, vinyl ether, etc .; consisting of an organosiloxane bond Silicone resins or modified products thereof (for example, modified products by alkyd resin, polyester resin, epoxy resin, polyurethane, polyimide, etc.); polyamide; polyester; polyurethane; polycarbonate; urea resin; melamine resin; benzoguanamine resin; Examples thereof include polyimide resins and derivatives thereof. These may be used individually by 1 type and may use 2 or more types together. Among these, a silicone resin is preferable.

  There is no restriction | limiting in particular as said silicone resin, According to the objective from the generally known silicone resin, it can select suitably, For example, straight silicone resin which consists only of organosiloxane bonds, alkyd, polyester , Silicone resins modified with epoxy, acrylic, urethane and the like.

  Examples of the straight silicone resin include KR271, KR272, KR282, KR252, KR255, KR152 (manufactured by Shin-Etsu Chemical Co., Ltd.), SR2400, SR2405, SR2406 (manufactured by Toray Dow Corning Silicone).

  Specific examples of the modified silicone resin include epoxy-modified product: ES-1001N, acrylic-modified silicone: KR-5208, polyester-modified product: KR-5203, alkyd-modified product: KR-206, and urethane-modified product: KR-. 305 (manufactured by Shin-Etsu Chemical Co., Ltd.), epoxy-modified product: SR2115, alkyd-modified product: SR2110 (manufactured by Toray Dow Corning Silicone), and the like.

  The silicone resin can be used alone, but a crosslinking reactive component, a charge amount adjusting component, and the like can be used at the same time. Examples of the crosslinking reactive component include a silane coupling agent. Examples of the silane coupling agent include methyltrimethoxysilane, methyltriethoxysilane, octyltrimethoxysilane, aminosilane coupling agent, and the like.

-Filler-
There is no restriction | limiting in particular as said filler, According to the objective, it can select suitably, For example, a conductive filler, a nonelectroconductive filler, etc. are mentioned. These may be used individually by 1 type and may use 2 or more types together. Among these, it is preferable to contain a conductive filler and a non-conductive filler in the coating layer.

The conductive filler refers to a filler having a powder specific resistance value of 100 Ω · cm or less.
The said nonelectroconductive filler points out the filler whose powder specific resistance value exceeds 100 ohm * cm.
The powder specific resistance value of the filler is measured by a powder resistance measurement system (MCP-PD51, manufactured by Dia Instruments) and a resistivity meter (4-terminal 4-probe system, Loresta GP, manufactured by Mitsubishi Chemical Analytech). Can be measured under the conditions of a sample of 1.0 g, an electrode interval of 3 mm, a sample radius of 10.0 mm, and a load of 20 kN.

--Conductive filler--
There is no restriction | limiting in particular as said electroconductive filler, According to the objective, it can select suitably. For example, a conductive filler formed as a layer of tin dioxide or indium oxide on a substrate such as aluminum oxide, titanium oxide, zinc oxide, barium sulfate, silicon oxide, zirconium oxide, etc .; a conductive filler formed using carbon black, etc. It is done. Among these, a conductive filler containing aluminum oxide, titanium oxide, and barium sulfate is preferable.

--Non-conductive filler--
There is no restriction | limiting in particular as said nonelectroconductive filler, According to the objective, it can select suitably. For example, a non-conductive filler formed using aluminum oxide, titanium oxide, barium sulfate, zinc oxide, silicon dioxide, zirconium oxide, or the like can be given. Among these, non-conductive fillers containing aluminum oxide, titanium oxide, and barium sulfate are preferable.

<Carrier manufacturing method>
There is no restriction | limiting in particular as a manufacturing method of the said carrier, Although it can select suitably according to the objective, The said resin and the said filler are contained in the surface of the said core particle using a fluid bed type coating apparatus. The method of manufacturing by apply | coating a coating layer forming solution is preferable. In addition, when apply | coating the said coating layer forming solution, you may advance condensation of the resin contained in the said coating layer, and after apply | coating the said coating layer forming solution, condensation of the resin contained in the said coating layer You may proceed.

  There is no restriction | limiting in particular as the condensation method of the said resin, According to the objective, it can select suitably, For example, the method etc. which give a heat | fever, light, etc. to the said coating layer formation solution, etc. are mentioned. .

-Weight average particle diameter Dw of carrier-
The weight average particle diameter Dw of the carrier refers to the particle diameter at an integrated value of 50% in the particle size distribution of the core particles obtained by a laser diffraction / scattering method. There is no restriction | limiting in particular as the weight average particle diameter Dw of the said carrier, Although it can select suitably according to the objective, 10 micrometers-80 micrometers are preferable, and 20 micrometers-65 micrometers are more preferable.

  For the measurement of the weight average particle diameter Dw of the carrier, the particle size distribution (relationship between the number frequency and the particle diameter) of the particles measured on the basis of the number is used using a Microtrac particle size distribution meter (HRA9320-X100, manufactured by Honeywell). Measured under the conditions described below and calculated using the following formula (II). Each channel represents a length for dividing the particle size range in the particle size distribution chart into measurement width units, and the lower limit value of the particle size stored in each channel is adopted as the representative particle size.

Dw = {1 / Σ (nD3)} × {Σ (nD4)} (II)
However, in said formula (II), D represents the representative particle size (micrometer) of the carrier which exists in each channel, and n represents the total number of the carriers which exist in each channel.

[Measurement condition]
[1] Particle size range: 100 μm to 8 μm
[2] Channel length (channel width): 2 μm
[3] Number of channels: 46
[4] Refractive index: 2.42

  When the developer is a two-component developer, the mixing ratio of the toner and the carrier in the two-component developer is preferably such that the mass ratio of the toner to the carrier is 2.0 to 12.0% by mass, More preferably, it is 2.5-10.0 mass%.

(Toner storage unit)
The toner storage unit in the present invention refers to a unit in which toner is stored in a unit having a function of storing toner. Here, examples of the toner storage unit include a toner storage container, a developing device, and a process cartridge.
The toner container is a container that contains toner.
The developing device is a unit having a means for containing and developing toner.
The process cartridge is a cartridge in which at least the image carrier and the developing unit are integrated, accommodates toner, and is detachable from the image forming apparatus. The process cartridge may further include at least one selected from charging means, exposure means, and cleaning means.

  Since the toner storage unit of the present invention is mounted on an image forming apparatus to form an image, image formation is performed using the toner of the present invention, so that low-temperature fixability, heat-resistant storage stability, charging stability, and image quality are achieved. Has the effect of being excellent in.

(Image forming method and image forming apparatus)
The image forming method of the present invention includes an electrostatic latent image forming step of forming an electrostatic latent image on an electrostatic latent image carrier, and developing the electrostatic latent image using the toner or developer of the present invention. A developing process for forming a visible image, a transferring process for transferring the visible image onto a recording medium, and a fixing process for fixing the transferred image transferred onto the recording medium. Furthermore, it has other processes suitably selected as necessary, for example, a static elimination process, a cleaning process, a recycling process, a control process, and the like.

  The image forming apparatus of the present invention uses the electrostatic latent image carrier, the electrostatic latent image forming means for forming an electrostatic latent image on the electrostatic latent image carrier, and the toner or developer of the present invention. Developing means for developing the electrostatic latent image to form a visible image, transfer means for transferring the visible image onto a recording medium, and fixing means for fixing the transferred image transferred onto the recording medium And have. Furthermore, other means appropriately selected as necessary, for example, a static elimination means, a cleaning means, a recycling means, a control means and the like are provided. Details will be described below.

-Electrostatic latent image forming step and electrostatic latent image forming means-
The electrostatic latent image forming step is a step of forming an electrostatic latent image on the electrostatic latent image carrier.
The electrostatic latent image carrier (sometimes referred to as “electrophotographic photosensitive member” or “photosensitive member”) is not particularly limited in terms of material, shape, structure, size, etc. Although it can be selected as appropriate, the shape thereof is preferably a drum shape, and examples of the material thereof include inorganic photoreceptors such as amorphous silicon and selenium, organic photoreceptors (OPC) such as polysilane and phthalopolymethine, and the like. Is mentioned. Among these, an organic photoreceptor (OPC) is preferable in that a higher definition image can be obtained.

The formation of the electrostatic latent image can be performed, for example, by uniformly charging the surface of the electrostatic latent image carrier and then performing imagewise exposure, and is performed by electrostatic latent image forming means. Can do.
The electrostatic latent image forming unit includes, for example, a charging unit (charger) that uniformly charges the surface of the electrostatic latent image carrier, and an exposure that exposes the surface of the electrostatic latent image carrier imagewise. Means (exposure unit).

The charging can be performed, for example, by applying a voltage to the surface of the electrostatic latent image carrier using the charger.
The charger is not particularly limited and may be appropriately selected depending on the purpose. For example, a known contact charging device including a conductive or semiconductive roll, brush, film, rubber blade, etc. And non-contact chargers utilizing corona discharge such as corotrons and corotrons.
The charger is preferably one that is arranged in contact or non-contact with the electrostatic latent image carrier and charges the surface of the electrostatic latent image carrier by applying a direct current and an alternating voltage.
Further, the charger is a charging roller disposed in a non-contact proximity to the electrostatic latent image carrier via a gap tape, and the electrostatic latent image is carried by applying a direct current and an alternating voltage to the charging roller. Those that charge the body surface are preferred.

The exposure can be performed, for example, by exposing the surface of the latent electrostatic image bearing member imagewise using the exposure device.
The exposure device is not particularly limited as long as it can expose the surface of the electrostatic latent image carrier charged by the charger so as to form an image to be formed, and is appropriately selected according to the purpose. For example, various exposure devices such as a copying optical system, a rod lens array system, a laser optical system, and a liquid crystal shutter optical system can be used.
In the present invention, a back light system in which imagewise exposure is performed from the back side of the electrostatic latent image carrier may be employed.

-Development process and development means-
The developing step is a step of developing the electrostatic latent image with the toner to form a visible image.
The visible image can be formed, for example, by developing the electrostatic latent image using the toner, and can be performed by the developing unit.
The developing unit preferably includes, for example, at least a developing unit that accommodates the toner and can apply the toner to the electrostatic latent image in a contact or non-contact manner, and includes a toner-containing container. Etc. are more preferable.

The developing device may be a monochromatic developing device or a multi-color developing device, and has, for example, an agitator that frictionally agitates and charges the toner and a rotatable magnet roller. A thing etc. are mentioned suitably.
In the developing device, for example, the toner and the carrier are mixed and agitated, and the toner is charged by friction at that time, and held on the surface of the rotating magnet roller in a raised state to form a magnetic brush. . Since the magnet roller is disposed in the vicinity of the electrostatic latent image carrier (photoconductor), a part of the toner constituting the magnetic brush formed on the surface of the magnet roller is electrically attracted. It moves to the surface of the electrostatic latent image carrier (photoconductor) by force. As a result, the electrostatic latent image is developed with the toner, and a visible image is formed with the toner on the surface of the electrostatic latent image carrier (photoconductor).

-Transfer process and transfer means-
The transfer step is a step of transferring the visible image onto a recording medium. After the primary transfer of the visible image onto the intermediate transfer member using an intermediate transfer member, the visible image is transferred onto the recording medium. A primary transfer step of forming a composite transfer image by transferring a visible image onto an intermediate transfer body using two or more colors, preferably full color toner as the toner, and a composite transfer image; A mode including a secondary transfer step of transferring the transfer image onto the recording medium is more preferable.
The transfer can be performed, for example, by charging the latent electrostatic image bearing member (photoconductor) of the visible image using a transfer charger, and can be performed by the transfer unit. The transfer means includes a primary transfer means for transferring a visible image onto an intermediate transfer member to form a composite transfer image, and a secondary transfer means for transferring the composite transfer image onto a recording medium. Embodiments are preferred.
The intermediate transfer member is not particularly limited and may be appropriately selected from known transfer members according to the purpose. For example, a transfer belt and the like are preferable.

The transfer means (the primary transfer means and the secondary transfer means) is a transfer for peeling and charging the visible image formed on the electrostatic latent image carrier (photoconductor) to the recording medium side. It is preferable to have at least a vessel. The number of the transfer means may be one, or two or more.
Examples of the transfer device include a corona transfer device using corona discharge, a transfer belt, a transfer roller, a pressure transfer roller, and an adhesive transfer device.
The recording medium is not particularly limited and can be appropriately selected from known recording media (recording paper).

-Fixing process and fixing means-
The fixing step is a step of fixing the visible image transferred to the recording medium using a fixing device, and may be performed each time the developer of each color is transferred to the recording medium, or the developer of each color. On the other hand, it may be carried out at the same time in a state where these are laminated.
There is no restriction | limiting in particular as said fixing device, Although it can select suitably according to the objective, A well-known heating-pressing means is suitable. Examples of the heating and pressing means include a combination of a heating roller and a pressing roller, a combination of a heating roller, a pressing roller, and an endless belt.
The fixing device includes a heating body including a heating element, a film in contact with the heating body, and a pressure member in pressure contact with the heating body through the film, and the film and the pressure member It is preferably a unit that heats and fixes a recording medium on which an unfixed image is formed. The heating in the heating and pressing means is usually preferably 80 ° C to 200 ° C.
In the present invention, for example, a known optical fixing device may be used together with or in place of the fixing step and the fixing unit depending on the purpose.

The neutralization step is a step of performing neutralization by applying a neutralization bias to the electrostatic latent image carrier, and can be suitably performed by a neutralization unit.
The neutralization means is not particularly limited, and may be appropriately selected from known neutralizers as long as it can apply a neutralization bias to the electrostatic latent image carrier. Preferably mentioned.

The cleaning step is a step of removing the toner remaining on the electrostatic latent image carrier and can be suitably performed by a cleaning unit.
The cleaning unit is not particularly limited, and may be selected from known cleaners as long as it can remove the toner remaining on the electrostatic latent image carrier. For example, a magnetic brush cleaner Suitable examples include electrostatic brush cleaners, magnetic roller cleaners, blade cleaners, brush cleaners, web cleaners, and the like.

The recycling step is a step of recycling the toner removed by the cleaning step to the developing unit, and can be suitably performed by the recycling unit. There is no restriction | limiting in particular as said recycling means, A well-known conveyance means etc. are mentioned.
The control step is a step of controlling each step, and each step can be suitably performed by a control means.
The control means is not particularly limited as long as the movement of each means can be controlled, and can be appropriately selected according to the purpose. Examples thereof include devices such as a sequencer and a computer.

  FIG. 2 shows a first example of the image forming apparatus of the present invention. The image forming apparatus 100 </ b> A includes a photosensitive drum 10, a charging roller 20, an exposure device, a developing device 40, an intermediate transfer belt 50, a cleaning device 60 having a cleaning blade, and a static elimination lamp 70.

  The intermediate transfer belt 50 is an endless belt stretched by three rollers 51 arranged on the inner side, and can move in the direction of the arrow in the figure. A part of the three rollers 51 also functions as a transfer bias roller that can apply a transfer bias (primary transfer bias) to the intermediate transfer belt 50. Further, a cleaning device 90 having a cleaning blade is disposed in the vicinity of the intermediate transfer belt 50. Further, a transfer roller 80 capable of applying a transfer bias (secondary transfer bias) for transferring the toner image to the transfer paper 95 is disposed opposite to the intermediate transfer belt 50.

  Further, around the intermediate transfer belt 50, a corona charging device 58 for applying a charge to the toner image transferred to the intermediate transfer belt 50 is connected to the photosensitive drum 10 with respect to the rotation direction of the intermediate transfer belt 50. It is disposed between the contact portion of the intermediate transfer belt 50 and the contact portion of the intermediate transfer belt 50 and the transfer paper 95.

  The developing device 40 includes a developing belt 41 and a black developing unit 45K, a yellow developing unit 45Y, a magenta developing unit 45M, and a cyan developing unit 45C provided around the developing belt 41. Each color developing unit 45 includes a developer container 42, a developer supply roller 43, and a developing roller (developer carrier) 44. The developing belt 41 is an endless belt stretched by a plurality of belt rollers, and can move in the direction of the arrow in the figure. Further, a part of the developing belt 41 is in contact with the photosensitive drum 10.

  Next, a method for forming an image using the image forming apparatus 100A will be described. First, the charging roller 20 is used to uniformly charge the surface of the photosensitive drum 10, and then the exposure light L is exposed to the photosensitive drum 10 using an exposure device (not shown) to form an electrostatic latent image. Form. Next, the electrostatic latent image formed on the photosensitive drum 10 is developed with the toner supplied from the developing device 40 to form a toner image. Further, after the toner image formed on the photosensitive drum 10 is transferred (primary transfer) onto the intermediate transfer belt 50 by the transfer bias applied from the roller 51, the transfer bias applied from the transfer roller 80 is used. Then, it is transferred (secondary transfer) onto the transfer paper 95. On the other hand, the photosensitive drum 10 on which the toner image is transferred to the intermediate transfer belt 50 is discharged by the discharging lamp 70 after the toner remaining on the surface is removed by the cleaning device 60.

  FIG. 3 shows a second example of the image forming apparatus used in the present invention. In the image forming apparatus 100B, the black developing unit 45K, the yellow developing unit 45Y, the magenta developing unit 45M, and the cyan developing unit 45C are arranged directly facing each other around the photosensitive drum 10 without providing the developing belt 41. Other than that, the configuration is the same as that of the image forming apparatus 100A.

  FIG. 4 shows a third example of the image forming apparatus used in the present invention. The image forming apparatus 100 </ b> C is a tandem type color image forming apparatus, and includes a copying apparatus main body 150, a paper feed table 200, a scanner 300, and an automatic document feeder (ADF) 400.

  The intermediate transfer belt 50 provided at the center of the copying apparatus main body 150 is an endless belt stretched around three rollers 14, 15 and 16, and can move in the direction of the arrow in the figure. In the vicinity of the roller 15, a cleaning device 17 having a cleaning blade for removing toner remaining on the intermediate transfer belt 50 on which the toner image has been transferred onto the recording paper is disposed. While facing the intermediate transfer belt 50 stretched by the rollers 14 and 15, electrostatic latent image carriers 10Y, 10C, 10M and 10K of yellow, cyan, magenta and black are juxtaposed along the transport direction. .

  An exposure device 21 is disposed in the vicinity of the image forming unit 120. Further, the secondary transfer belt 24 is disposed on the side of the intermediate transfer belt 50 opposite to the side on which the image forming unit 120 is disposed. The secondary transfer belt 24 is an endless belt stretched around a pair of rollers 23, and the recording paper and the intermediate transfer belt 50 conveyed on the secondary transfer belt 24 are between the rollers 16 and 23. Can touch.

  Further, in the vicinity of the secondary transfer belt 24, a fixing device 25 is provided with a fixing belt 26 that is an endless belt stretched between a pair of rollers, and a pressure roller 27 that is arranged to be pressed against the fixing belt 26. Is arranged. A sheet reversing device 28 for reversing the recording paper when an image is formed on both sides of the recording paper is disposed in the vicinity of the secondary transfer belt 24 and the fixing device 25.

  Next, a method for forming a full-color image using the image forming apparatus 100C will be described. First, a color document is set on the document table 130 of the automatic document feeder (ADF) 400, or the automatic document feeder 400 is opened and a color document is set on the contact glass 32 of the scanner 300 to automatically convey the document. The device 400 is closed. When the start switch is pressed, when an original is set on the automatic document feeder 400, after the original is conveyed and moved onto the contact glass 32, on the other hand, when the original is set on the contact glass 32, Immediately, the scanner 300 is driven, and the first traveling body 33 including the light source and the second traveling body 34 including the mirror travel. At this time, the reflected light from the original surface of the light irradiated from the first traveling body 33 is reflected by the second traveling body 34 and then received by the reading sensor 36 via the imaging lens 35, whereby the original is received. It is read and image information of black, yellow, magenta and cyan is obtained.

  The image information for each color is transmitted to the image forming unit 120 for each color, and a toner image for each color is formed. As shown in FIG. 5, each color image forming unit 120 includes a photosensitive drum 10, a charging roller 160 that uniformly charges the photosensitive drum 10, and the image information of each color, respectively. An exposure device that exposes the exposure light L to form an electrostatic latent image of each color; a developing device 61 that develops the electrostatic latent image with a developer of each color to form a toner image of each color; A transfer roller 62 for transferring onto the transfer belt 50, a cleaning device 63 having a cleaning blade, and a static elimination lamp 64 are provided.

  The toner images of the respective colors formed by the image forming units 120 of the respective colors are sequentially transferred (primary transfer) onto the intermediate transfer body 50 that is stretched and moved by the rollers 14, 15, and 16, and superimposed to form a composite toner image. It is formed.

  On the other hand, in the paper feed table 200, one of the paper feed rollers 142 is selectively rotated to feed recording paper from one of the paper feed cassettes 144 provided in multiple stages in the paper bank 143, and one sheet at a time by the separation roller 145. The paper is separated and sent to the paper feed path 146, transported by the transport roller 147, guided to the paper feed path 148 in the copying machine main body 150, and abutted against the registration roller 49 to stop. Alternatively, the paper feed roller is rotated to feed out the recording paper on the manual feed tray 18, separated one by one by the separation roller 52, guided to the manual paper feed path 53, and abutted against the registration roller 49 and stopped.

  The registration roller 49 is generally used while being grounded, but may be used in a state where a bias is applied in order to remove paper dust from the recording paper. Next, by rotating the registration roller 49 in synchronization with the composite toner image formed on the intermediate transfer belt 50, the recording paper is sent between the intermediate transfer belt 50 and the secondary transfer belt 24, and the composite toner image is sent. The toner image is transferred onto the recording paper (secondary transfer). The toner remaining on the intermediate transfer belt 50 to which the composite toner image has been transferred is removed by the cleaning device 17.

  The recording paper on which the composite toner image has been transferred is conveyed by the secondary transfer belt 24 and then the composite toner image is fixed by the fixing device 25. Next, the conveyance path of the recording paper is switched by the switching claw 55, and the recording paper is discharged onto the paper discharge tray 57 by the discharge roller 56. Alternatively, the recording path of the recording paper is switched by the switching claw 55, reversed by the sheet reversing device 28, an image is similarly formed on the back side, and then discharged onto the discharge tray 57 by the discharge roller 56. .

  According to the image forming method and the image forming apparatus of the present invention, high-quality images can be provided over a long period of time.

  EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, this invention is not limited to the following Example. In the description in the examples, [%] represents% by weight, and “part” represents “part by mass”.

(Synthesis Example A-1)
-Synthesis of polyester resin A-1-
Reaction 1: In a reaction vessel equipped with a nitrogen introduction tube, a dehydration tube, a stirrer and a thermocouple, bisphenol A ethylene oxide 3 mol adduct (EO) and bisphenol A propylene oxide 2 mol adduct (PO) and 1, 2-Propylene glycol (PG) in a molar ratio of 12/80/8, terephthalic acid (TPA) and adipic acid (ADA) in a molar ratio of 70/30, OH / COOH = 1.33, 500 ppm of titanium The reaction was carried out with tetraisopropoxide at 230 ° C. for 10 hours at normal pressure.
Reaction 2: Next, 25 parts of benzoic acid (BA) was added to the reaction vessel, and the reaction was carried out at a reduced pressure of 10 mmHg to 15 mmHg for 5 hours.
Reaction 3: Next, 10 parts of trimellitic anhydride (TMA) was placed in a reaction vessel and reacted at 180 ° C. and normal pressure for 3 hours to obtain [Polyester Resin A-1].

(Synthesis Examples A-2 to A-14)
-Synthesis of other polyester resin A-
[Polyester resin A-2] to [Polyester resin A-14] were obtained by Reaction 1 to Reaction 3 in the same manner as in Synthesis Example A-1. Table 1 shows the molar ratio of the alcohol component, the molar ratio of the carboxylic acid component, the OH / COOH ratio, the BA part, and the TMA part in each synthesis example.

(Synthesis Examples B-1 to B-7)
-Synthesis of polyester resin B-
[Polyester resin B-1] to [Polyester resin B-7] were obtained by Reaction 1 to Reaction 3 in the same manner as in Synthesis Example A-1. Table 2 shows the molar ratio of the alcohol component, the molar ratio of the carboxylic acid component, the OH / COOH ratio, the BA part, and the TMA part in each synthesis example. In Synthesis Example B-1, BA was not added in Reaction 2, and the reaction was performed at a reduced pressure of 10 mmHg to 15 mmHg for 5 hours.

(Synthesis Example C-1)
-Synthesis of polyester resin C-1-
In a reaction vessel equipped with a nitrogen introduction tube, a dehydration tube, a stirrer, and a thermocouple, bisphenol A ethylene oxide 2-mole adduct (EO) and bisphenol A propylene oxide 3-mole adduct (PO) in a molar ratio of 20 / 80, terephthalic acid (TPA), isophthalic acid (IPA) and trimellitic anhydride (TMA) in a molar ratio of 40/40/20, charged with OH / COOH = 1.1, together with 500 ppm of titanium tetraisopropoxide The reaction was carried out at 230 ° C. for 10 hours at normal pressure. Subsequently, after reacting under reduced pressure of 10 mmHg to 15 mmHg for 5 hours, 15 parts of trimellitic anhydride was added to the reaction vessel and reacted at 180 ° C. and normal pressure for 3 hours to obtain [Polyester Resin C-1].

-Preparation of masterbatch (MB)-
1,200 parts of water, carbon black (manufactured by Printex 35 Dexa) [DBP oil absorption = 42 mL / 100 mg, pH = 9.5] 540 parts and [polyester resin A-10] 1,200 parts were added, and a Henschel mixer (Mitsui (Mine Co., Ltd.), and the mixture was kneaded at 150 ° C. for 30 minutes using two rolls, rolled and cooled, and pulverized with a pulverizer to obtain [Masterbatch 1].

Example 1
<Preparation of toner>
-Raw material composition-
Binder resin 1: [Polyester resin A-1] 76 parts Binder resin 2: [Polyester resin C-1] 18 parts Colorant: [Masterbatch 1] 7 parts Charge control agent: Bontron E-84 (Orient Chemical Industries) 1 part Release agent: Carnauba wax (WA-05, manufactured by Celerica Noda) 6 parts

  The toner powder raw material was thoroughly mixed with a super mixer (SMV-200, manufactured by Kawata) to obtain a toner powder raw material mixture. This toner powder raw material mixture was supplied to a raw material supply hopper of a Busco kneader (TCS-100, manufactured by Buss Co.), and kneaded at a supply amount of 120 kg / h. The obtained kneaded product is rolled and cooled with a double belt cooler, coarsely pulverized with a hammer mill, finely pulverized with a jet airflow pulverizer (I-20 jet mill, manufactured by Nippon Pneumatic Co., Ltd.), and a wind classifier. Fine powder classification was performed using a DS-20 / DS-10 classifier (manufactured by Nippon Pneumatic Co., Ltd.) to prepare [Toner Base Particle 1].

-Mixed-
Hydrophobic silica (HDK-2000, manufactured by Wacker Chemie) is added to the above [toner base particle 1] in an amount of 1.5 parts with respect to 100 parts of the base particle, and a 20 L Henschel mixer (manufactured by Mitsui Mining). Mixing was performed at a peripheral speed of 33 m / s for 5 minutes. The above was air sieved with a 500 mesh sieve to obtain [Toner 1].

(Examples 2 to 19)
For Examples 2 to 19, [Toner 2] to [Toner 19] were obtained in the same manner as in Example 1 except for the type and number of binder resin 1 and the type and number of binder resin 2. Table 3 shows prescription conditions at the time of preparing each toner.

(Comparative Examples 1-6)
For Comparative Examples 1 to 6, [Toner 20] to [Toner 25] were obtained in the same manner as in Example 1 except for the type and number of binder resin 1 and the type and number of binder resin 2. Table 4 shows the prescription conditions at the time of preparation of the toner of each comparative example.

(Comparative Example 7)
“Toner 26” was obtained in the same manner as in Example 1 except that the raw material composition was changed as follows.
-Raw material composition-
Binder resin 1: [Polyester resin A-13] 46 parts Binder resin 2: [Polyester resin C-1] 18 parts Binder resin 3: [Polyester resin B-7] 30 parts Colorant: [Masterbatch 1] 7 parts Charge control agent: Bontron E-84 (manufactured by Orient Chemical Co., Ltd.) 1 part Mold release agent: Carnauba wax (WA-05, manufactured by Celalica Noda) 6 parts

(Synthesis Example D-1)
-Synthesis of polyester prepolymer-
In a reaction vessel equipped with a cooling tube, a stirrer and a nitrogen insertion tube, 720 parts by mass of bisphenol A ethylene oxide 2 mol adduct, 90 parts by mass of bisphenol A propylene oxide 2 mol adduct, 290 parts by mass of terephthalic acid, and tetrabutoxy titanate 1 A mass part was added, and the reaction was carried out for 8 hours while distilling off the generated water at 230 ° C. and normal pressure under a nitrogen stream. Subsequently, it was made to react under reduced pressure of 10-15 mmHg for 7 hours, and [intermediate polyester] was obtained. [Intermediate polyester] had a weight average molecular weight (Mw) of 9,300.

  Next, put 400 parts by mass of the obtained [intermediate polyester], 95 parts by mass of isophorone diisocyanate, and 500 parts by mass of ethyl acetate in a reaction vessel equipped with a cooling pipe, a stirrer, and a nitrogen insertion pipe. The mixture was reacted at 80 ° C. for 8 hours to obtain a 50% by mass ethyl acetate solution of [polyester prepolymer: D-1] having an isocyanate group at the terminal. [Polyester prepolymer: D-1] had a free isocyanate mass% of 1.47%.

(Example 20)
<Manufacture of toner 27 (ester elongation method)>
-Preparation of release agent dispersion-
70 parts by weight of Carnauba wax (WA-05, manufactured by Celerica Noda), 140 parts by weight of [Polyester Resin A-1], and 290 parts by weight of ethyl acetate are placed in a container equipped with a stirring bar and a thermometer. The temperature was raised to 75 ° C. and held at 75 ° C. for 1.5 hours, then cooled to 30 ° C. in 1 hour, and using a bead mill (Ultra Visco Mill, manufactured by IMEX), the liquid feeding speed was 5 kg / hr, the disk circumference Dispersion was carried out under the conditions of a filling rate of 6 m / sec, 0.5% zirconia beads at 80% by volume, and 3 passes to obtain [release agent dispersion].

-Production of oil phase 1-
In a container equipped with a thermometer and a stirrer, 113 parts by weight of [Polyester Resin A-1], 88 parts by weight of [Mold Release Agent Dispersion], 42 parts by weight of [Masterbatch 1], and 150 parts by weight of ethyl acetate are put. After pre-dispersing with a stirrer, the mixture was stirred with a TK homomixer (manufactured by Tokushu Kika Co., Ltd.) at a rotational speed of 5,000 rpm, and uniformly dissolved and dispersed to obtain [Oil Phase 1].

-Production of aqueous dispersion of resin fine particles-
In a reaction vessel equipped with a stirrer and a thermometer, 600 parts by mass of water, 120 parts by mass of styrene, 100 parts by mass of methacrylic acid, 45 parts by mass of butyl acrylate, sodium salt of alkylallylsulfosuccinate (Eleminol JS-2, Sanyo Chemical Industries) 10 parts by mass) and 1 part by mass of ammonium persulfate were charged and stirred for 20 minutes at 400 rpm, and a white emulsion was obtained. This emulsion was heated to raise the temperature in the system to 75 ° C. and reacted for 6 hours.

  Further, 30 parts by mass of a 1% ammonium persulfate aqueous solution was added and aged at 75 ° C. for 6 hours to obtain [Aqueous dispersion of resin fine particles]. The volume average particle diameter of the particles contained in this [resin fine particle aqueous dispersion] was 60 nm, the weight average molecular weight of the resin component was 140,000, and Tg was 73 ° C.

-Preparation of aqueous phase-
990 parts by mass of water, 83 parts by mass of an aqueous dispersion of resin fine particles, 37 parts by mass of a 48.5% by mass aqueous solution of sodium dodecyl diphenyl ether disulfonate (Eleminol MON-7, manufactured by Sanyo Chemical Industries), and 90 parts by mass of ethyl acetate Parts were mixed and stirred to obtain [Aqueous phase].

-Emulsification or dispersion-
To 393 parts by mass of [Oil Phase 1], 58 parts by mass of an ethyl acetate solution of [polyester prepolymer: D-1] and 3.5 parts by mass of a 50% by mass ethyl acetate solution of isophoronediamine are added, and a TK homomixer is added. The mixture was stirred at a rotational speed of 5,000 rpm (made by Tokushu Kika Co., Ltd.), and uniformly dissolved and dispersed to obtain [Oil Phase 1 ′]. Next, 550 parts by mass of [Aqueous Phase] is put in another container in which a stirrer and a thermometer are set, and while stirring at 11,000 rpm with a TK homomixer (made by Tokushu Kika Kogyo Co., Ltd.), 1 '] was added and emulsified for 1 minute to obtain [Emulsified slurry 1].

-Solvent removal-Washing-Drying-
[Emulsion slurry 1] was charged into a container equipped with a stirrer and a thermometer, and the solvent was removed at 30 ° C. under reduced pressure for 8 hours to obtain [Slurry 1]. The obtained [Slurry 1] was kept at 45 ° C. for 2 hours, then filtered under reduced pressure, and the following washing treatment was performed.
(1) 100 parts by mass of ion-exchanged water was added to the filter cake, mixed with a TK homomixer (5 minutes at a rotation speed of 6,000 rpm), and then filtered.
(2) After adding 100 parts by mass of ion-exchanged water to the filter cake of (1) and mixing with a TK homomixer (5 minutes at a rotation speed of 6,000 rpm), 1% by mass hydrochloric acid is about pH 3.3 with stirring. The mixture was added until the mixture was stirred, and stirring was continued for 1 hour in that state, followed by filtration.
(3) Add 300 parts by mass of ion-exchanged water to the filter cake of (2) above, mix with a TK homomixer (5 minutes at 6,000 rpm) and then filter twice to obtain filter cake 1 It was.

The obtained filter cake 1 was dried at 40 ° C. for 48 hours in a circulating dryer. Thereafter, the mixture was sieved with a 75 μm mesh to produce [Toner Base Particles 27].
The obtained [Toner Base Particles 27] were mixed and air sieved under the same conditions as in Example 1 to obtain [Toner 27].

(Examples 21 to 25)
<Production of Toner 28 to Toner 32 (Ester Elongation Method)>
In Examples 21 to 25, [Toner 28] to [Toner 32] were prepared in the same manner as in Example 20 except that the number of [polyester prepolymer: D-1] and the slurry heating and holding conditions after solvent removal were changed. Produced. Table 5 shows the production conditions of each toner.

(Measurement)
The following measurements were performed on the toners obtained in the above Examples and Comparative Examples. The measurement results are shown in Tables 6-8.

<GPC measurement>
The molecular weight distribution measured by GPC of the hexafluoroisopropanol (HFIP) soluble component of the toner was measured as follows.

Gel permeation chromatography (GPC) measuring device: HLC-8220GPC (manufactured by Tosoh Corporation)
Column: TSK GMH _HR (manufactured by Tosoh Corporation)
Temperature: 40 ° C
Solvent: Hexafluoroisopropanol (HFIP) Solution flow rate: 0.2 mL / min
Sample: Hexafluoroisopropanol (HFIP) sample solution adjusted to 0.15% by mass Pretreatment of sample: Toner was dissolved in hexafluoroisopropanol (HFIP) at 0.15% by mass and filtered through a 0.45 μm filter, and the filtrate Was used as a sample.

  The measurement was performed by injecting 10 μL of the HFIP sample solution. In measuring the molecular weight of the sample, the molecular weight distribution of the sample was calculated from the relationship between the logarithmic value of the calibration curve prepared with several types of polymethyl methacrylate standard samples and toluene and the number of counts.

  EasiVial PM polymethylmethacrylate (PL2020-0200) was used as a polymethylmethacrylate standard sample for preparing a calibration curve, and Wako Pure Chemical Industries, Ltd. was used as toluene. An RI (refractive index) detector was used as the detector.

  About the GPC measurement result of hexafluoroisopropanol (HFIP), the vertical axis is plotted with the molecular weight distribution curve with the intensity on the vertical axis and the molecular weight on the horizontal axis, and the maximum peak intensity in the range of the molecular weight of 1,000 to 10,000. The intensity of the entire molecular weight distribution curve was corrected with the following point as 100.

  The molecular weight distribution measured by GPC of the THF soluble component of the toner is measured as follows.

Gel permeation chromatography (GPC) measuring device: GPC-8220GPC (manufactured by Tosoh Corporation)
Column: TSK-GEL SUPER HZ2000, TSK-GEL SUPER HZ2500, TSK-GEL SUPER HZ3000
Temperature: 40 ° C
Solvent: THF
Flow rate: 0.35 ml / min
Sample: THF sample solution adjusted to 0.15% by mass Sample pretreatment: The toner was dissolved in tetrahydrofuran THF (containing a stabilizer, manufactured by Wako Pure Chemical Industries, Ltd.) at 0.15 wt% and filtered through a 0.45 μm filter. The filtrate was used as a sample.

  The measurement was performed by injecting 10 μL of the THF sample solution. In measuring the molecular weight of the sample, the molecular weight distribution of the sample was calculated from the relationship between the logarithmic value of the calibration curve prepared from several types of monodisperse polystyrene standard samples and the number of counts.

  As a standard polystyrene sample for preparing a calibration curve, as a standard polystyrene sample for preparing a calibration curve, TSK standard polystyrene manufactured by Tosoh Corporation having a molecular weight of 37200, 6200, 2500, 589, molecular weights 28400, 20298, 10900, 4782, 1689, 1309 Standard polystyrene and toluene manufactured by Showa Denko were used. An RI (refractive index) detector was used as the detector.

  Regarding the measurement result of THF-soluble GPC, the vertical axis is the intensity, the horizontal axis is the molecular weight distribution curve with the molecular weight, and the maximum peak intensity in the molecular weight range of 1,000 to 15,000 The intensity of the entire molecular weight distribution curve is corrected as 100.

  Moreover, the weight average molecular weight Mw and the weight average molecular weight (Mw) / number average molecular weight (Mn) of the THF-soluble component were determined from the obtained molecular weight distribution curve.

<Tg>
The glass transition temperature Tg was measured using DSC-6220R (manufactured by Seiko Instruments Inc.). First, after heating from room temperature to 150 degreeC with the temperature increase rate of 10 degree-C / min, it was left to stand at 150 degreeC for 10 minutes. Next, the sample was cooled to room temperature and allowed to stand for 10 minutes, and then again heated to 150 ° C. at a temperature increase rate of 10 ° C./min. As a result, a base line below the glass transition point and a curve portion corresponding to a height of the base line above the glass transition point being 1/2 were obtained, and Tg was obtained.

<Acid value AV, hydroxyl value OHV>
The acid value was determined according to JIS K0070-1992, and the hydroxyl value was determined according to JIS K0070-1966.

<Tan δ>
It measured using the dynamic-viscoelasticity measuring apparatus (ARES (made by TA Instruments)). The sample was molded into a pellet having a diameter of 8 mm and a thickness of 1 to 2 mm, fixed to a parallel plate having a diameter of 8 mm, stabilized at 40 ° C., a frequency of 1 Hz (6.28 rad / s), and a strain of 0.1% ( In the strain amount control mode), the temperature was raised to 200 ° C. at a rate of temperature rise of 2.0 ° C./min.

<Soxhlet extraction with ethyl acetate>
For the Soxhlet extraction, a general Soxhlet extraction apparatus was used. In a soxhlet extraction cylindrical filter paper whose exact weight was measured, 0.5 g of toner was precisely weighed, 200 g of ethyl acetate was placed in a flat bottom flask (300 ml), and the cylindrical filter paper was mounted in a soxhlet extraction tube. A flat bottom flask, a Soxhlet extraction tube, and a cooling tube were connected, the flat bottom flask was heated with a mantle heater, and extraction operation was performed for 10 hours after the ethyl acetate in the flask began to boil. The extracted cylindrical filter paper was sufficiently washed with ethyl acetate, and then ethyl acetate as a solvent was sufficiently dried. The content of the insoluble component gel amount of ethyl acetate contained in the toner was calculated from the sample weight measured first, the weight of the cylindrical filter paper, and the amount of extraction residue after extraction and drying.

<Flow tester>
The 1/2 method softening point (T1 / 2) was determined from a flow curve measured using an elevated flow tester CFT500 type (manufactured by Shimadzu Corporation). Measurement conditions were as follows.

[Measurement condition]
Load: 10kg / cm ²
Temperature increase rate: 3.0 ° C / min
Die diameter: 0.50mm
Die length: 1.0mm
Measurement temperature: 40 ° C to 200 ° C

  In Tables 6 to 8, the HFIP soluble component P0 (Mp) is the peak top of the main peak (P0) in the molecular weight distribution measured by GPC of the hexafluoroisopropanol (HFIP) soluble component of the toner. The molecular weight means the HFIP soluble component P1 intensity difference when the peak top (P1) of an arbitrary peak having a molecular weight in the range of 250 to 2,500 is selected. This means the difference between the maximum value and the minimum value of the peak intensity in the range of the molecular weight of ± 100, and the HFIP soluble component P2, P2 ′ intensity is the peak in the range of the molecular weight of 15,000 or more and 35,000 or less. Means the intensity of the peak top (P2) or shoulder peak (P2 '), and the THF soluble components P2 and P2' In the molecular weight distribution measured by GPC of the soluble component, it means a peak having a peak top or a shoulder peak in a molecular weight range of 15,000 to 35,000, and the HFIP soluble component P3 intensity range is the toner. In the molecular weight distribution measured by GPC of the hexafluoroisopropanol (HFIP) soluble component, it means an intensity in the range of a molecular weight of 100,000 to 300,000.

(Evaluation method and evaluation results)
The toners obtained in the above examples and comparative examples were evaluated as follows. The evaluation results are shown in Tables 9-11.

<Low temperature fixability>
The image is a cardboard ("copy printing paper <135>"; manufactured by NBS Ricoh Co., Ltd.) using an evaluation machine that was tuned by modifying the image forming apparatus ("IPSIO Color 8100"; manufactured by Ricoh Co., Ltd.) to an oilless fixing system. Was adjusted so that 1.0 ± 0.1 mg / cm ² of toner was developed with a solid image. The fixing roll temperature at which the residual ratio of the image density after rubbing the obtained fixed image with a pad was 70% or more was determined as the minimum fixing temperature.

[Evaluation criteria]
A: Fixing lower limit is less than 120 ° C. ○: Fixing lower limit is 120 ° C. or more and less than 135 Δ: Fixing lower limit is 135 ° C. or more and less than 150 ×: Fixing lower limit is 150 ° C. or more

<Heat resistant storage stability>
The toner was stored at 50 ° C. for 8 hours, and then sieved with a 42 mesh sieve for 2 minutes. The residual rate on the wire mesh was used as an index for heat resistant storage stability. The heat resistant storage stability was evaluated in the following four stages. “◎” and “◯” are levels that have no problem at all, “Δ” is a level that is slightly inferior in storage stability but is not problematic for practical use, and “×” is a level that is problematic for practical use.

[Evaluation criteria]
◎: Less than 10% ○: 10 or more and less than 20% △: 20 or more and less than 30% ×: 30% or more

<Charging stability>
Using each developer, an endurance test for outputting 100,000 sheets continuously was performed using a character image pattern having an image area ratio of 12%, and the change in the charge amount at that time was evaluated. A small amount of developer was collected from the sleeve, the change in charge amount was determined by the blow-off method, and evaluated according to the following criteria.

[Evaluation criteria]
A: Change in charge amount is less than 3 μc / g ○: Change in charge amount is 3 μc / g or more and less than 6 μc / g Δ: Change in charge amount is 6 μc / g or more and less than 10 μc / g ×: Change in charge amount is 10 μc / g greater than g

<Image intensity>
The state of scratches after a pencil scratch test using a pencil of hardness B in accordance with JIS K5600-5-4 for the test paper fixed at a fixing belt temperature of 160 ° C. in the low temperature fixability test. From the evaluation, the following criteria were used.
〔Evaluation criteria〕
◎: No scratch marks are seen, and no image is lost even when rubbed with an eraser. ○: No scratch marks are seen, but a slight image loss occurs when rubbed with an eraser. △: Scratch marks are almost seen. Although there is no image missing when rubbed with an eraser x: Scratches are seen, and there is an image missing that can be clearly seen without rubbing with an eraser

<Separation stability>
The separation resistance required to peel the recording medium from the fixing roller was measured using a recording medium pressing force measuring apparatus shown in FIG. 6 to evaluate the separation stability.
In the measuring device for the pressing force of the recording medium, the recording medium S is conveyed in a form of being pressed against the measuring claw 405 when a load 406 is applied as shown in the figure. At this time, the pressing force of the recording medium is read by the load cell 403 provided at the other end of the measurement claw 405 via the fulcrum 404. The value read by the load cell 403 is the separation resistance. The measurement claw 405 is provided on the side of the fixing roller 401 immediately after the nip portion between the fixing roller 401 and the pressure roller 402.

At this time, the measuring device for the pressing force of the recording medium was fixed to the fixing portion of the image forming apparatus so that the measuring claw 405 was at an appropriate position by a jig. Also, A4 paper type 6200 paper (manufactured by Ricoh) was used as the recording medium S, and a 3 cm × 10 cm unfixed solid image with a toner adhesion amount of 0.85 ± 0.01 mg / cm ² was measured 3 cm from the top to the left and right. Created in the center of the direction. The separation resistance generated when this unfixed solid image was fixed at a fixing temperature of 160 ° C. was measured and evaluated according to the following criteria. “◎” is very good, “◯” is good, “Δ” is an acceptable level, and “×” is a level that cannot be used practically.

[Evaluation criteria]
A: Separation resistance is less than 200 gf B: Separation resistance is 200 gf or more and 300 gf or less Δ: Separation resistance is greater than 300 gf, 400 gf or less ×: Separation resistance is more than 400 gf

<Glossiness>
Using an image forming apparatus, a copy test was performed on POD gloss coated paper (basis weight: 128 g / m ² ) manufactured by Oji Paper Co., Ltd. The evaluation image of glossiness is a 3 cm × 10 cm solid image with an adhesion amount of 0.40 ± 0.02 mg / cm ^{2 on} Oji Paper's POD gloss coated paper (basis weight: 128 g / m ² ), and 3 cm from the top to the left and right Formed in the center of the direction. This image was fixed in 5 ° C increments in the range of linear velocity of paper feed: 280 mm / sec, surface pressure: 1.2 kgf / cm ² , nip width: 11 mm, fixing temperature: 160 ° C to 180 ° C, and glossy. An evaluation image of degree was used. The glossiness was evaluated by measuring 60 ° glossiness at any 10 locations using a gloss meter VG-7000 (manufactured by Nippon Denshoku Industries Co., Ltd.), and calculating the average value as glossiness. Of the evaluation images at each fixing temperature, the value with the highest glossiness was taken as the maximum glossiness and evaluated according to the following criteria. “◎” is very good, “◯” is good, “Δ” is an acceptable level, and “×” is a level that cannot be used practically.

[Evaluation criteria]
◎: Maximum glossiness is 30% or more ○: Maximum glossiness is 25% or more and less than 30% △: Maximum glossiness is 20% or more and less than 25% ×: Maximum glossiness is less than 20%

<Gloss unevenness>
First, using the image forming apparatus, the evaluation chart (FIG. 7) was applied to a Mondi Color Copy 300 (basis weight: 300 g / m ² ) manufactured by mondi at an adhesion amount of 1.00 ± 0.03 mg / cm ² . The first image and the second solid image are formed in succession, and the fixing temperature is changed by changing the linear velocity of paper feed: 400 mm / second, surface pressure: 1.6 kgf / cm ² , and nip width: 15 mm. The second fixed image at each fixing temperature was used as an evaluation image for gloss unevenness. The evaluation of the gloss afterimage was carried out by measuring the 60 degree glossiness of each of the evaluation sites 1 and 2 of the evaluation image using a gloss meter VG-7000 (manufactured by Nippon Denshoku Industries Co., Ltd.). The average glossiness was determined, and the fixing temperature at which the difference in glossiness was 20% or more was examined. The fixing temperature at which the difference in glossiness is 20% or more is 190 ° C. or more, or the case where the difference in glossiness is not 20% or more is ◯, the case where it is 180 ° C. or more and less than 190 ° C. The case of less than Δ was judged as Δ, and the case of less than 170 ° C. was judged as ×.

<Comprehensive judgment>
The evaluation criteria for comprehensive judgment are as follows. “◎” is very good, “◎” is very good, “◯” is good, “Δ” is acceptable, and “×” is a level that cannot be used practically.
“◎◎”, “◎”, “○”, “△” were accepted, and “×” was rejected.

[Evaluation criteria]
◎◎: There are three or more ◎, and Δ and X are absent. ◎: ◎ are 1 and 2, and △ and X are absent. ○: The above “◎◎” and “◎” are not included, and Δ is within one. And x none △: two or more △ and x none x: one or more x

  As is clear from the evaluation results in Tables 9 to 10, Examples 1 to 25 are sufficiently excellent in low-temperature fixability, heat-resistant storage stability, charging stability, and image strength. On the other hand, with respect to Comparative Examples 1 to 7, at least one of low-temperature fixability, heat-resistant storage stability, and charging stability has a practically problematic result.

  Further, as is apparent from the evaluation results of Table 11, when a toner is produced by the ester elongation method, the 1/2 method softening point (T1 / 2) in the flow curve measured using the elevated flow tester of the toner In Examples 21 to 24, which are in the preferred range, in addition to good low-temperature fixability, heat-resistant storage stability, and charging stability, excellent separation stability and high gloss images can be obtained. Among them, Example 22 shows particularly excellent results.

10 Photosensitive drum 10K Electrostatic latent image carrier for black 10Y Electrostatic latent image carrier for yellow 10M Electrostatic latent image carrier for magenta 10C Electrostatic latent image carrier for cyan 14 Support roller 15 Support roller 16 Support roller 17 Cleaning device 18 Manual feed tray 20 Charging roller 21 Exposure device 22 Secondary transfer device 23 Roller 24 Secondary transfer belt 25 Fixing device 26 Fixing belt 27 Pressure roller 28 Sheet reversing device 32 Contact glass 33 First traveling body 34 Second traveling body 35 imaging lens 36 reading sensor 40 developing device 41 developing belt 42K developer accommodating portion 42Y developer accommodating portion 42M developer accommodating portion 42C developer accommodating portion 43K developer supplying roller 43Y developer supplying roller 43M developer supplying roller 43C developing Agent supply roller 44K Developing roller 44Y Developing roller 44M Developing roller 44C Developing roller 45K Black developing unit 45Y Yellow developing unit 45M Magenta developing unit 45C Cyan developing unit 49 Registration roller 50 Intermediate transfer belt 51 Roller 52 Separating roller 53 Manual feed path 54 Manual tray 55 Switching claw 56 Discharge roller 57 Discharge tray 57 60 Cleaning device 61 Developing device 62 Transfer roller 63 Cleaning device 64 Static elimination lamp 70 Static elimination lamp 80 Transfer roller 90 Cleaning device 95 Transfer paper 100A, 100B, 100C Image forming device 120 Image forming unit 130 Document table 142 Paper feed roller 143 Paper bank 144 Paper feed cassette 145 Separation roller 146 Paper feed path 147 Transport roller 148 Paper feed path 150 Copying apparatus main body 160 Charging roller 200 Paper feed table 300 Yana 400 Automatic document feeder (ADF)
401 fixing roller 402 pressure roller 403 load cell 404 fulcrum 405 measuring claw 406 load S recording medium N nip

Japanese Patent No. 4118498 Japanese Patent No. 4156759 Japanese Patent No. 4993533 Japanese Patent No. 4565054 Japanese Patent No. 4397038

Claims (9)

A toner containing at least a binder resin and a release agent,
In the molecular weight distribution measured by GPC of the hexafluoroisopropanol (HFIP) soluble component of the toner, the peak top molecular weight of the main peak (P0) is in the range of 3,000 to 10,000, and the molecular weight is 250 to 2. When the peak top (P1) of an arbitrary peak existing in the range of 500 or less is selected, the difference between the maximum value and the minimum value of the peak intensity defined below in the range of the molecular weight ± 100 of the peak top (P1) Is a peak top (P2) or shoulder peak (P2 ') of a peak having an intensity of 30 or more and 80 or less in a molecular weight range of 15,000 or more and 35,000 or less,
In addition, the molecular weight distribution measured by GPC of the tetrahydrofuran (THF) soluble component of the toner does not have a peak having a peak top or a shoulder peak in a molecular weight range of 15,000 to 35,000. toner.
Peak intensity: GPC measurement is plotted with a molecular weight distribution curve in which the vertical axis is the intensity and the horizontal axis is the molecular weight, and the peak intensity value that is maximum in the range of the molecular weight of 1,000 to 10,000 is 100. Relative value   2. The toner according to claim 1, wherein the difference between the maximum value and the minimum value of the peak intensity in the range of the molecular weight ± 100 of the peak top (P1) is 20 or less.   The molecular weight distribution measured by GPC of the hexafluoroisopropanol (HFIP) soluble component of the toner has a molecular weight range of 100,000 to 300,000 (P3) in the range of 10 to 30. The toner according to claim 1 or 2. The toner has a glass transition temperature Tg of 45 ° C. to 60 ° C .;
In the molecular weight distribution by GPC of the tetrahydrofuran (THF) soluble component of the toner, the weight average molecular weight Mw is 6,000 to 15,000, and the weight average molecular weight (Mw) / number average molecular weight (Mn) is 7.5 or less. The toner according to claim 1, wherein the toner is a toner.   The value of the ratio tan δ (G ″ / G ′) between the storage elastic modulus G ′ (Pa) and the loss viscosity G ″ (Pa) measured by measuring the viscoelasticity of the toner is 120 ° C. or higher and 160 ° C. or lower. The toner according to claim 1, wherein the toner has a temperature range of 0.40 to 0.90.   The toner according to claim 1, wherein the toner has a gel content of 10% by mass to 30% by mass obtained by Soxhlet extraction with ethyl acetate.   The toner according to claim 1, wherein the binder resin is a polyester resin.   A toner containing unit containing the toner according to claim 1. An electrostatic latent image carrier;
Electrostatic latent image forming means for forming an electrostatic latent image on the electrostatic latent image carrier;
Developing means for developing the electrostatic latent image to form a visible image using the toner according to claim 1;
Transfer means for transferring the visible image onto a recording medium;
An image forming apparatus comprising: fixing means for fixing the transferred image transferred onto the recording medium.