toner

Abstract

To provide a toner that achieves a balance of low-temperature fixation, bend resistance, and image stacking performance, while also offering excellent abrasion resistance. [Solution] A toner having toner particles containing a resin component, wherein the resin component contains a crystalline vinyl resin, and in differential scanning calorimetry of the toner, in heating process 1 in which the temperature is raised from 20°C to 180°C at a heating rate of 10°C / min, there is one endothermic peak originating from the crystalline vinyl resin, and in heating process 2 following heating process 1, the temperature is lowered from 180°C to 20°C at a cooling rate of 10°C / min, and then the temperature is raised again from 20°C to 180°C at a heating rate of 10°C / min, there are two endothermic peaks originating from the crystalline vinyl resin, and the amount of heat absorbed by the endothermic peak originating from the crystalline vinyl resin in heating process 1 and the amount of heat absorbed by each of the two endothermic peaks originating from the crystalline vinyl resin in heating process 2 satisfy a specific relationship.

Description

[Technical Field]

[0001] This disclosure relates to toner. [Background technology]

[0002] Traditionally, energy conservation has been considered a major technical challenge in electrophotographic equipment, and significant reductions in the amount of heat required for the fuser have been explored. In toner, there is a growing need for so-called "low-temperature fixing," which enables fixing with low energy consumption.

[0003] To enable fixing at low temperatures, a method using crystalline resin as the binder resin is being considered. Amorphous resins, commonly used as binder resins for toner, do not show a clear endothermic peak in differential scanning calorimeter (DSC) measurements. However, when the toner contains crystalline resin components, an endothermic peak (melting point) appears in DSC measurements. Crystalline resins have the property of hardly softening at temperatures below their melting point due to the regular arrangement of their molecular chains. Furthermore, above the melting point, the crystals melt rapidly, resulting in a sharp decrease in viscosity. Because of these excellent sharp-melt properties, crystalline resins are attracting attention as useful materials for improving the low-temperature fixation of toners.

[0004] Examples of crystalline resins include toners using crystalline vinyl resins that have long-chain alkyl groups in their side chains. Typically, crystalline vinyl resins have a structure in which long-chain alkyl groups are bonded as side chains to the main chain. The long-chain alkyl groups in the side chains crystallize together, and the molecules form a lamellar structure in which they are regularly arranged, thus becoming a crystalline resin. While this type of structure allows molecules to easily unravel and is advantageous for low-temperature fixing, it also makes the material prone to brittle fracture when subjected to impact.

[0005] Brittle fracture can be broadly classified into cleavage fracture, which occurs along specific crystal planes within the crystal grains, and intergranular fracture, which occurs along the grain boundaries. Cracks that form due to impact tend to propagate in a limited direction: parallel to the lamellar structure in cleavage fractures, and along the direction of the crystal interface in intergranular fractures. In particular, in toners containing a large amount of crystalline resin, crack extension is significant because the crystal planes and crystal interfaces extend long in specific directions. For these reasons, toners containing a large amount of crystalline resin may have insufficient resistance to bending, as streaks and cracks caused by bending of the fixed image tend to spread easily.

[0006] Patent Document 1 discloses a toner that uses a crystalline resin and maximizes the compatibility of the crystalline resin with the amorphous resin after fixing, thereby exhibiting excellent low-temperature fixing properties. In the toner of Patent Document 1, the compatibility between the crystalline resin and the amorphous resin is very high, resulting in an extremely low degree of crystallinity of the crystalline resin on the fixed image. In such a toner, the cleavage characteristic of crystalline resins is not present on the fixed image, thus improving the bending resistance of the fixed image, which is a problem with toners using crystalline resins. [Prior art documents] [Patent Documents]

[0007] [Patent Document 1] Japanese Patent Publication No. 2014-106464 [Patent Document 2] Japanese Patent Publication No. 2022-163694 [Patent Document 3] Japanese Patent Publication No. 2021-140029 [Overview of the project] [Problems that the invention aims to solve]

[0008] On the other hand, the toners described above tend to become sticky in high-temperature and high-humidity environments due to their low degree of crystallinity. As a result, it has been found that when printed papers are stacked and left for a long time, the papers can stick together, and when they are separated, defects are likely to occur in the image, resulting in insufficient image stacking capacity.

[0009] Patent Document 2 discloses a toner that achieves both low-temperature fixability and bending resistance by adding amorphous vinyl resin with different polymerizable monomer ratios to a crystalline vinyl resin. In such a toner, the crystalline state is maintained even on the fixed image, resulting in good image stacking performance. Nevertheless, it has become clear that there are still challenges in image stacking performance in high-temperature and high-humidity environments and in the high-speed printing processes of recent years, due to the large amount of amorphous material remaining and insufficient control of the crystalline state. Patent Document 3 discloses a toner that improves the durability of the fixed image against external forces by using two types of crystalline resins in combination, thereby achieving both resistance to bending and image stacking. However, the toner described in Patent Document 3 uses two types of crystalline resin, resulting in two endothermic peaks with different melting points. When two endothermic peaks exist, the decrease in viscosity with increasing temperature occurs gradually from the lower endothermic peak to the higher endothermic peak. As a result, it has been found that the sharp melting properties and low-temperature fixing properties, which are characteristic of toners using crystalline resin, tend to decrease.

[0010] At least one aspect of this disclosure aims to provide a toner that achieves a balance of low-temperature fixability, bend resistance, and image stacking ability, and further exhibits excellent abrasion resistance. [Means for solving the problem]

[0011] At least one aspect of this disclosure is a toner having toner particles containing a resin component, The resin component contains crystalline vinyl resin, When the temperature at which the differential curve of the DSC endothermic curve shows a minimum value during heating in the differential scanning calorimetry of the toner is defined as the peak top temperature, In the temperature rising process 1 where the temperature is raised from 20°C to 180°C at a rate of 10°C / min, there is one endothermic peak derived from the crystalline vinyl resin, Following the temperature rising process 1, the temperature is lowered from 180°C to 20°C at a rate of 10°C / min, and then in the temperature rising process 2 where the temperature is raised again from 20°C to 180°C at a rate of 10°C / min, there are two endothermic peaks derived from the crystalline vinyl resin, In the temperature rising process 1, the endothermic peak derived from the crystalline vinyl resin is defined as endothermic peak P1, In the temperature rising process 2, among the two endothermic peaks derived from the crystalline vinyl resin, the endothermic peak having the peak top temperature on the low temperature side is defined as endothermic peak P21, and the endothermic peak having the peak top temperature on the high temperature side is defined as endothermic peak P22, [[ID=⑨]]When the heat absorption amount of the endothermic peak P1 is S1 (J / g), the heat absorption amount of the endothermic peak P21 is S21 (J / g), and the heat absorption amount of the endothermic peak P22 is S22 (J / g), the S1, the S21, and the S22 satisfy the following formulas (1) to (3), Formula (1) S1 ≥ (S21 + S22) ≥ S1 × 0.25 Formula (2) S21 ≥ S1 × 0.10 Formula (3) S22 ≥ S1 × 0.10 It relates to a toner characterized by the above.

Effect of the Invention

[0012] According to at least one aspect of the present disclosure, it is possible to provide a toner that achieves both low-temperature fixing property, bend resistance, and image loading property, and further has excellent abrasion resistance.

Mode for Carrying Out the Invention

[0013] The In this disclosure, descriptions of numerical ranges such as "XX or greater and YY or less" or "XX to YY" mean a numerical range that includes the lower and upper limits, unless otherwise specified. When numerical ranges are described in steps, the upper and lower limits of each numerical range can be any combination. In addition, in this disclosure, a description such as "at least one selected from the group consisting of XX, YY, and ZZ" means any of the following: XX, YY, ZZ, a combination of XX and YY, a combination of XX and ZZ, a combination of YY and ZZ, or a combination of XX, YY, and ZZ.

[0014] "(Meth)acrylic acid ester" means acrylic acid ester and / or methacrylic acid ester. A "monomer unit" refers to the reacted form of monomer substances in a polymer. For example, one carbon-carbon bond in the main chain formed by the polymerization of polymerizable monomers in a polymer is considered one unit. A polymerizable monomer can be represented, for example, by the following formula (C). [ka] In the above formula (C), R A R represents a hydrogen atom or an alkyl group (preferably an alkyl group having 1 to 3 carbon atoms, and more preferably a methyl group), B This represents a monovalent group. "Crystalline resin" refers to a resin that exhibits a clear endothermic peak in differential scanning calorimeter (DSC) measurements. "Endothermic peak" refers to a peak with a local minimum in the differential curve of the DSC endothermic curve during heating in differential scanning calorimeter measurements.

[0015] The inventors have found that the above problem can be solved by appropriately controlling the crystalline state of the crystalline vinyl resin in the toner on the fixed image, that is, by appropriately controlling the number of endothermic peaks and the amount of endothermic heat absorbed in the DSC endothermic curve during different heating processes when the toner undergoes different heating processes in differential scanning calorimetry.

[0016] The toner relating to this disclosure is a toner having toner particles containing a resin component, The resin component contains crystalline vinyl resin, When the temperature at which the differential curve of the DSC endothermic curve shows a minimum value during heating in the differential scanning calorimetry of the toner is defined as the peak top temperature, In heating process 1, where the temperature is raised from 20°C to 180°C at a heating rate of 10°C / min, there is one endothermic peak originating from the crystalline vinyl resin. In heating process 2, which follows heating process 1 by cooling from 180°C to 20°C at a rate of 10°C / min, and then heating again from 20°C to 180°C at a rate of 10°C / min, two endothermic peaks originating from the crystalline vinyl resin are present. In the heating process 1, the endothermic peak originating from the crystalline vinyl resin is defined as endothermic peak P1. In the heating process 2, of the two endothermic peaks originating from the crystalline vinyl resin, the endothermic peak with the lower temperature peak top temperature is defined as endothermic peak P21, and the endothermic peak with the higher temperature peak top temperature is defined as endothermic peak P22. When the amount of heat absorbed at the endothermic peak P1 is S1 (J / g), the amount of heat absorbed at the endothermic peak P21 is S21 (J / g), and the amount of heat absorbed at the endothermic peak P22 is S22 (J / g), S1, S21, and S22 satisfy the following formulas (1) to (3): Formula (1) S1≧(S21+S22)≧S1×0.25 Formula (2) S21≧S1×0.10 Formula (3) S22≧S1×0.10 It is characterized by the following:

[0017] The toner relating to this disclosure is a toner having toner particles containing a resin component, wherein the resin component contains a crystalline vinyl resin. In the differential scanning calorimetry of the toner, the temperature at which the differential curve of the DSC endothermic curve shows a minimum value during heating is defined as the peak top temperature. Furthermore, in the differential scanning calorimetry of the toner, the process of heating from 20°C to 180°C at a heating rate of 10°C / min is defined as heating process 1. During heating process 1, there is one endothermic peak originating from the crystalline vinyl resin.

[0018] During the heating process 1, the presence of a single endothermic peak originating from the crystalline vinyl resin results in good heat resistance at temperatures below the melting point, and above the melting point, the crystals rapidly melt, exhibiting the sharp melt properties characteristic of crystalline resins. As a result, the low-temperature fixation of the toner is improved. On the other hand, if there are two or more endothermic peaks in the heating process 1, the decrease in toner viscosity due to the temperature rise during fixing occurs gradually from the low-temperature endothermic peak to the high-temperature endothermic peak, resulting in a decrease in sharp meltability. As a result, low-temperature fixing performance tends to decrease.

[0019] To control the endothermic peak in the heating process 1 to a single peak, one method is to appropriately select the type and amount of crystalline vinyl resin used when using two or more types of crystalline vinyl resins, thereby controlling the affinity between the crystalline vinyl resins and facilitating the formation of a eutectic state. Furthermore, control can also be achieved in the toner particle manufacturing process by adjusting the cooling rate, annealing temperature after cooling, and duration. Specific examples of methods for controlling the endothermic peak to a single peak will be described later.

[0020] In the differential scanning calorimetry described above, the heating process 2 is defined as a process in which the temperature is lowered from 180°C to 20°C at a rate of 10°C / min following the heating process 1, and then raised again from 20°C to 180°C at a rate of 10°C / min. During this heating process 2, there are two endothermic peaks originating from the crystalline vinyl resin. The presence of two endothermic peaks originating from crystalline vinyl resin during the heating process 2 indicates that two different crystalline states coexist in the toner.

[0021] In the heating process 1 described above, the endothermic peak originating from the crystalline vinyl resin is denoted as P1. In the heating process 2 described above, of the two endothermic peaks originating from the crystalline vinyl resin, the endothermic peak on the lower temperature side is denoted as endothermic peak P21, and the endothermic peak on the higher temperature side is denoted as endothermic peak P22. That is, endothermic peak P21 is an endothermic peak with a peak top temperature on the lower temperature side, and endothermic peak P22 is an endothermic peak with a peak top temperature on the higher temperature side. When the amount of heat absorbed by the endothermic peak P1 is S1 (J / g), the amount of heat absorbed by the endothermic peak P21 is S21 (J / g), and the amount of heat absorbed by the endothermic peak P22 is S22 (J / g), then S1, S21, and S22 satisfy the following equation (1). Formula (1) S1≧(S21+S22)≧S1×0.25

[0022] As shown in equation (1), the amount of heat absorbed in heating process 2 (S21 + S22) is less than or equal to the amount of heat absorbed in heating process 1 (S1). This suggests that the amount of crystals in each peak in heating process 2 is smaller and the crystal diameters are smaller compared to heating process 1.

[0023] In summary, if two endothermic peaks originating from the crystalline vinyl resin exist in heating process 2, and the amount of heat absorbed in heating process 2 (S21 + S22) is less than or equal to the amount of heat absorbed in heating process 1 (S1), then it can be considered that two types of crystalline states with small crystal diameters are mixed in the toner in the fixed image.

[0024] When the toner on the fixed image is in this state, the direction of the crystal planes and crystal interfaces is not limited. Therefore, even if cracks are generated inside the crystal or at the crystal interface, the progressing cracks will immediately reach crystal planes or crystal interfaces with different extension directions. Since cracks do not propagate through crystal planes or crystal interfaces with different extension directions, crack propagation is more likely to stop in such toner. As a result, the cleavage of the resin component in the toner decreases, and consequently, the bending resistance of the fixed image improves.

[0025] If there is no endothermic peak during the heating process 2, the control of the crystalline state in the toner is insufficient, making the image prone to stickiness in high-temperature, high-humidity environments. Furthermore, the heat resistance to frictional heat generated when the fixed image is rubbed is reduced, making the image density more likely to decrease when the image is rubbed. In other words, the abrasion resistance is reduced. On the other hand, if there is only one endothermic peak in the heating process 2, and the amount of heat absorbed is sufficient to ensure good image stacking, then there is no mixing of crystalline states in the toner in the fixed image, and large crystals with similar structures exist. In this case, the direction of crack extension becomes longer at the crystal planes and crystal interfaces, and when cracks form, they are more likely to lead to large fractures. Therefore, the bending resistance tends to decrease.

[0026] Furthermore, if there are three or more endothermic peaks in heating process 2, the area of ​​the crystal interface increases excessively due to the increase in crystalline states. Since the crystal interface is one of the causes of cleavage in crystalline resins, an excessive increase in the area of ​​the crystal interface tends to reduce bending resistance. In addition, it becomes difficult to control the endothermic peak in heating process 1 to one, and as sharp melt properties decrease, low-temperature fixing properties also tend to decrease.

[0027] To control the endothermic peaks in heating process 2 to two distinct peaks, one method is to appropriately select the monomer units used for each crystalline vinyl resin, for example, when using two or more types of crystalline vinyl resins. In heating process 2, the endothermic peak appears because it reflects the melting point characteristic of crystalline vinyl resins. Therefore, by adjusting the carbon chain length of the monomer units of two or more types of crystalline vinyl resins and the molecular weight of the crystalline vinyl resins, the melting point of each crystalline vinyl resin can be controlled, resulting in two distinct peaks. Specific examples of methods for controlling the endothermic peaks to two will be described later.

[0028] Furthermore, by controlling the affinity between the crystalline vinyl resin and other materials such as wax, it is possible to control the endothermic peaks in heating process 2 to two distinct peaks. Since the affinity between different crystalline vinyl resins and other materials varies, this difference can be used to change the melting point of a specific crystalline vinyl resin, thereby controlling the endothermic peaks to two distinct peaks.

[0029] As shown in equation (1), the total amount of endothermic heat absorbed by the endothermic peak originating from the crystalline vinyl resin in heating process 2 (S21 + S22) is 25% or more of the amount of endothermic heat absorbed by the endothermic peak originating from the crystalline vinyl resin in heating process 1 (S1). Meeting the above criteria indicates that the degree of crystallinity of the crystalline resin in the toner in the fixed image is sufficient. Therefore, stickiness of the image after fixing is less likely to occur, and the image stacking properties of the fixed image are good.

[0030] In terms of further improving image stacking performance, it is more preferable that the total amount of heat absorbed by the endothermic peak originating from the crystalline vinyl resin in heating process 2 is 30% or more of the amount of heat absorbed by the endothermic peak originating from the crystalline vinyl resin in heating process 1, and even more preferable that it is 45% or more. That is, it is more preferable that (S21+S22)≧S1×0.30 is satisfied, and even more preferable that (S21+S22)≧S1×0.45 is satisfied.

[0031] As mentioned above, the total amount of heat absorbed by the endothermic peak originating from the crystalline vinyl resin during heating process 2 ( S21 + S22) is less than or equal to the amount of heat absorbed by the endothermic peak derived from the crystalline vinyl resin during the heating process 1, S1. The upper limit of (S21 + S22) is not particularly limited as long as the above is satisfied, but it is preferably 95% or less of S1, and more preferably 90% or less. That is, it is preferable that S1 × 0.95 ≥ (S21 + S22), and more preferably that S1 × 0.90 ≥ (S21 + S22).

[0032] Furthermore, the toner satisfies the condition that the amount of heat absorbed by the two endothermic peaks originating from the crystalline vinyl resin in heating process 2 is 10.0% or more of the amount of heat absorbed by the endothermic peaks originating from the crystalline vinyl resin in heating process 1. That is, the toner satisfies the following equations (2) and (3). Formula (2) S21≧S1×0.10 Formula (3) S22≧S1×0.10

[0033] When the toner satisfies equations (2) and (3) above, the degree of crystallinity is sufficient in the crystalline state that exhibits each endothermic peak. As a result, the image stacking of the fixed image is improved. In terms of further improving image stacking performance, it is preferable that the endothermic amount of each peak originating from the crystalline vinyl resin in heating process 2 be 15.0% or more, and more preferably 25.0% or more, than the endothermic amount of the endothermic peak originating from the crystalline vinyl resin in heating process 1. That is, it is preferable that S21 ≥ S1 × 0.15 and S22 ≥ S1 × 0.15 are satisfied. Furthermore, it is more preferable that S21 ≥ S1 × 0.25 and S22 ≥ S1 × 0.25 are satisfied.

[0034] The upper limit of the endothermic amount of each peak originating from the crystalline vinyl resin in heating process 2 is not particularly limited as long as the above is satisfied, but for example, it is preferably 80.0% or less of the endothermic amount of the endothermic peak originating from the crystalline vinyl resin in heating process 1, more preferably 70.0% or less, and even more preferably 60.0% or less. For example, it is preferable that S1 × 0.80 ≥ S21, more preferably that S1 × 0.70 ≥ S21, and even more preferably that S1 × 0.60 ≥ S21. Also, it is preferable that S1 × 0.80 ≥ S22, more preferably that S1 × 0.70 ≥ S22, and even more preferably that S1 × 0.60 ≥ S22.

[0035] S1 is preferably 10.0 (J / g) or more and 30.0 (J / g) or less, in that it exhibits the sharp melt properties characteristic of crystalline resins while suppressing bending resistance. S1 is more preferably 13.0 (J / g) or more and 27.0 (J / g) or less, and even more preferably 20.0 (J / g) or more and 25.0 (J / g) or less.

[0036] Furthermore, in terms of achieving a high level of both bending resistance and image loading performance, S21 is preferably 2.0 (J / g) to 13.0 (J / g), more preferably 5.0 (J / g) to 10.0 (J / g), and even more preferably 7.3 (J / g) to 9.2 (J / g). From a similar viewpoint, S22 is preferably 2.0 (J / g) to 10.0 (J / g), more preferably 3.0 (J / g) to 7.0 (J / g), and even more preferably 4.2 (J / g) to 5.3 (J / g). From a similar viewpoint, S21 + S22 is preferably 5.0 (J / g) to 20.0 (J / g), more preferably 7.0 (J / g) to 17.0 (J / g), and even more preferably 11.5 (J / g) to 14.5 (J / g).

[0037] To control the amount of heat absorbed at each endothermic peak so that equations (1) to (3) are all satisfied, methods such as appropriately controlling the type of crystalline vinyl resin used, the amount of additives other than binder resins such as wax, and the cooling rate, annealing temperature, and time in the toner particle manufacturing process can be used. Specifically, the following methods can be used.

[0038] As a means of increasing S1, for example, in the toner manufacturing method described later, it is advisable to reduce the degree of crystallinity of the crystalline vinyl resin by increasing the cooling rate after polymerization is completed and performing annealing for a short time after cooling. To reduce S1, for example, one can increase the degree of crystallinity of the crystalline vinyl resin by slowing down the cooling rate and performing the annealing for a longer period of time. The cooling rate after polymerization and the specific conditions for the annealing process will be described later.

[0039] One way to increase S21 is, for example, in crystalline vinyl resins associated with the endothermic peak on the low-temperature side, to increase the polarity of the crystalline vinyl resin other than the long-chain alkyl moieties, thereby making it easier for the long-chain alkyl moieties to aggregate and increasing the degree of crystallinity. As a means of reducing S21, for example, in crystalline vinyl resins related to the endothermic peak on the low-temperature side, it is advisable to reduce the polarity of the crystalline vinyl resin other than the long-chain alkyl moieties, thereby making it difficult for the long-chain alkyl moieties to aggregate and lowering the degree of crystallinity.

[0040] One way to increase S22 is, for example, to increase the amount of wax added to the crystalline vinyl resin that has the effect of acting as a crystallization nucleating agent in relation to the endothermic peak on the high-temperature side. One way to reduce S22 is, for example, to reduce the amount of wax added that acts as a nucleating agent for crystallization in crystalline vinyl resins associated with the endothermic peak on the high-temperature side. The preferred range for the amount of wax to be added will be discussed later.

[0041] To increase the sum of S21 and S22, one can appropriately combine the methods for increasing S21 and S22 described above. To reduce S21+S22, one can appropriately combine the methods for reducing S21 and S22 described above.

[0042] When the peak top temperature of the endothermic peak P1 is denoted as T1 (°C), it is preferable that T1 is between 50.0°C and 80.0°C. Having a T1 of 50.0°C or higher suppresses a rapid decrease in toner viscosity in high-temperature, high-humidity storage environments, thereby further improving heat-resistant storage. A T1 of 53.0°C or higher is more preferable, and 55.0°C or higher is even more preferable.

[0043] Furthermore, when T1 is 80.0°C or lower, the viscosity of the toner decreases even when the fuser temperature is low, resulting in better low-temperature fixing performance. To further improve low-temperature fixing performance, T1 is more preferably 65.0°C or lower, and even more preferably 62.0°C or lower.

[0044] In other words, by having T1 within the above range, a toner that achieves both heat resistance and low-temperature fixing properties can be obtained. T1 is more preferably 53.0°C to 70.0°C, even more preferably 55.0°C to 65.0°C, and even more preferably 55.0°C to 62.0°C.

[0045] Methods for controlling the peak top temperature T1 within the above range include, for example, appropriately selecting the alkyl chain length of the monomer unit used in the crystalline vinyl resin and controlling the molecular weight of the crystalline vinyl resin.

[0046] When the peak top temperature of the endothermic peak P21 is denoted as T21 (°C), it is preferable that T21 is 45.0°C or higher. It is more preferable that T21 is 50.0°C or higher. Furthermore, a temperature of 55.0℃ or higher is even more preferable. Having a T21 temperature of 45.0°C or higher improves heat resistance to frictional heat generated when the fixed image is rubbed. This suppresses the decrease in image density before and after rubbing, further improving abrasion resistance. In addition, if the difference between T22 and T21 (T22-T21), described later, is within a specific range, abrasion resistance can be further improved.

[0047] The upper limit of T21 is not particularly limited, but it is usually 85.0°C or lower. That is, T21 is preferably 45.0°C or higher and 85.0°C or lower, more preferably 50.0°C or higher and 85.0°C or lower, and even more preferably 55.0°C or higher and 85.0°C or lower. Methods for controlling the peak top temperature T21 within the above range include, for example, appropriately selecting the alkyl chain length of the monomer unit used in the crystalline vinyl resin and controlling the molecular weight of the crystalline vinyl resin.

[0048] When the peak top temperature of the endothermic peak P21 is T21 (°C) and the peak top temperature of the endothermic peak P22 is T22 (°C), it is preferable that T21 and T22 satisfy the following formula (4). Formula (4) 20.0≧(T22-T21)≧3.0

[0049] A difference of 3.0°C or more between T22 and T21 (T22-T21) indicates that crystals in two different crystalline states are sufficiently separated within the resin component. In other words, it prevents the crystalline vinyl resin from partially forming a eutectic state and suppresses the formation of large crystal clusters. In such cases, cleavage can be suppressed, and bending resistance is further improved. A value of (T22-T21) of 3.5 or more is more preferable, and 4.0 or more is even more preferable.

[0050] Furthermore, when the difference between T22 and T21 is 20.0°C or less, it is easier to suppress the excessive formation of a eutectic state between high-melting-point materials such as wax and crystalline vinyl resin. As a result, the melting point of the high-melting-point material can be maintained at a high level, and the heat resistance to frictional heat generated when the fixed image is rubbed is further improved, thus improving abrasion resistance. The value of (T22-T21) is more preferably 15.0 or less, and even more preferably 10.0 or less.

[0051] Methods for controlling the relationship between T22 and T21 to satisfy equation (4) include, for example, appropriately selecting the alkyl chain length of the monomer unit used in the crystalline vinyl resin and controlling the molecular weight of the crystalline vinyl resin.

[0052] The toner particles contain a resin component. The resin component contains a crystalline vinyl resin. The resin component may contain crystalline vinyl resin A, crystalline vinyl resin B, amorphous polyester resin C, and styrene acrylic resin. The resin component can be a binder resin. The resin component is, for example, a resin other than wax.

[0053] The following describes crystalline vinyl resins. The content of crystalline vinyl resin in the resin component contained in the toner particles is preferably 30.0% by mass or more and 60.0% by mass or less. More preferably, the above percentage is 33.0% by mass or more and 55.0% by mass or less, and even more preferably 35.0% by mass or more and 50.0% by mass or less.

[0054] When the resin component contains 30.0% or more by mass of crystalline vinyl resin, the toner has a sufficient amount of crystalline components, resulting in a pronounced sharp melt property characteristic of crystalline resins. Therefore, low-temperature fixing performance is improved. Furthermore, the content of crystalline vinyl resin in the resin components is 60.0% by mass or less. Because the toner does not contain an excessive amount of crystalline components, cleavage, which is characteristic of crystalline resins, is suppressed, and bending resistance is further improved. In other words, by keeping the proportion of crystalline vinyl resin in the resin components within the above range, both excellent low-temperature fixation and bending resistance can be achieved.

[0055] The crystalline vinyl resin preferably has monomer units (a) represented by the following formula (5). [ka] (In formula (5), R 1 L represents a hydrogen atom or a methyl group. 1 (where m represents a single bond, ester bond, or amide bond. m is an integer between 15 and 30.) In other words, the monomer unit (a) of the crystalline vinyl resin has a long-chain alkyl group (alkyl group with 16 to 31 carbon atoms) as a side chain of the vinyl polymer crystalline vinyl resin. As a result, a toner is obtained in which the crystalline vinyl resin has crystalline properties and excellent low-temperature fixability and heat-resistant storage properties.

[0056] By polymerizing a (meth)acrylic acid ester having an alkyl group with 16 to 31 carbon atoms as a polymerizable monomer, it is possible to incorporate monomer unit (a) as a monomer unit in a crystalline vinyl resin. As a result, a crystalline vinyl resin having monomer unit (a) represented by formula (5) above can be obtained.

[0057] One method for introducing the monomer unit (a) into a crystalline vinyl resin is to polymerize a (meth)acrylic acid ester as follows. Examples include (meth)acrylic acid esters having an alkyl group with 16 to 31 carbon atoms [(meth)acrylate cetyl, (meth)acrylate stearyl, (meth)acrylate nonadecyl, (meth)acrylate eicosyl, (meth)acrylate heneicosanyl, (meth)acrylate behenyl, (meth)acrylate lignoceryl, (meth)acrylate ceryl, (meth)acrylate octacosyl, (meth)acrylate myricyl, etc.].

[0058] Of these, from the viewpoint of low-temperature fixability and heat-resistant storage of the toner, monomer unit (a) is preferably at least one selected from the group consisting of (meth)acrylic acid esters having a linear alkyl group having 16 to 31 carbon atoms, more preferably at least one selected from the group consisting of (meth)acrylic acid esters having an alkyl group having 18 to 30 carbon atoms, and even more preferably at least one selected from the group consisting of linear stearyl (meth)acrylate and behenyl (meth)acrylate.

[0059] That is, in formula (1) above, the number of carbon atoms (m) is preferably an integer between 15 and 29, more preferably an integer between 17 and 29, and even more preferably an integer between 17 and 21. Also, R 1 It is preferable that it is a hydrogen atom. The crystalline vinyl resin may have only one type of monomer unit (a), or it may have two or more types.

[0060] The content of monomer units (a) in the crystalline vinyl resin is preferably 40.0% to 100.0% by mass, more preferably 50.0% to 100.0% by mass, and even more preferably 60.0% to 100.0% by mass. The above-mentioned content ratio of monomer unit (a) in the crystalline vinyl resin represents the total content ratio of monomer unit (a) represented by formula (1) in the crystalline vinyl resin. If the crystalline vinyl resin contains two or more types of monomer unit (a), it represents the total content ratio of all monomer unit (a).

[0061] The crystalline vinyl resin preferably contains crystalline vinyl resin A, in which the content of monomer unit (a) is 50.0% by mass or more and 70.0% by mass or less, and crystalline vinyl resin B, in which the content of monomer unit (a) is 80.0% by mass or more and 100.0% by mass or less.

[0062] By using two types of crystalline vinyl resins A and B with different monomer unit (a) content ratios in combination, the phenomenon of the endothermic peak increasing from one to two (peak splitting) from heating process 1 to heating process 2 becomes more likely to occur in differential scanning calorimetry of toner. In other words, by using crystalline vinyl resin A and crystalline vinyl resin B in combination, it becomes easier to obtain the toner according to this disclosure.

[0063] When the difference in the content ratio of monomer unit (a) in crystalline vinyl resin A and crystalline vinyl resin B is 50.0% by mass or less, the molecular structures of the two types of crystalline vinyl resins become similar, allowing them to exhibit moderately similar crystallization behavior. Therefore, it becomes easier to control the heating process 1 so that there is one endothermic peak. In addition, by adjusting the cooling and annealing conditions, the control of the endothermic peak in the heating process 1 can be made more precise. The specific conditions for the cooling and annealing processes will be described later.

[0064] Furthermore, a difference of 10.0% by mass or more between the content ratio of monomer unit (a) in crystalline vinyl resin A and the content ratio of monomer unit (a) in crystalline vinyl resin B creates a sufficient difference, resulting in the presence of two types of crystalline vinyl resin with appropriately different crystallization behaviors. As a result, it becomes easier to control the heating process 2 so that there are two endothermic peaks. In addition, by adjusting the cooling and annealing conditions, and by using materials that can form a eutectic state, such as wax, it becomes easier to precisely control the endothermic peak during the heating process 2. The specific conditions for the cooling and annealing processes will be described later.

[0065] The monomer unit (a) content in crystalline vinyl resin A is more preferably 53.0% by mass or more and 67.0% by mass or less, and even more preferably 55.0% by mass or more and 65.0% by mass or less. Furthermore, the monomer unit (a) content in crystalline vinyl resin B is more preferably 85.0% by mass or more and 100.0% by mass or less, and even more preferably 90.0% by mass or more and 100.0% by mass or less.

[0066] It is more preferable that the combination of two types of crystalline vinyl resins includes crystalline vinyl resin A, in which the content of monomer unit (a) is 55.0% by mass or more and 65.0% by mass or less, and crystalline vinyl resin B, in which the mass content of monomer unit (a) is 90.0% by mass or more and 100.0% by mass or less.

[0067] With the above combination, the difference in the content ratio of monomer unit (a) between crystalline vinyl resin A and crystalline vinyl resin B will be 25.0% by mass or more and 45.0% by mass or less, and the above The effect of peak splitting can be more pronounced. As a result, it becomes easier to obtain toner that has one endothermic peak originating from the crystalline vinyl resin in heating process 1 and two endothermic peaks originating from the crystalline vinyl resin in heating process 2, thereby achieving low-temperature fixability and particularly excellent bending resistance.

[0068] The crystalline vinyl resin may have other monomer units in addition to the monomer unit (a). A method for introducing other monomer units into the crystalline vinyl resin is, for example, polymerizing the (meth)acrylic acid ester with other vinyl monomers.

[0069] Other vinyl monomers include, for example, the following: (Meth)acrylic acid esters such as styrene, α-methylstyrene, methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl (meth)acrylate, t-butyl (meth)acrylate, and 2-ethylhexyl (meth)acrylate. Monomers having a urea group: For example, monomers obtained by reacting a carbon 3-22 amine [primary amines (n-butylamine, t-butylamine, propylamine, isopropylamine, etc.), secondary amines (di-normal ethylamine, di-normal propylamine, di-normal butylamine, etc.), aniline, and cycloxylamine, etc.)] with a carbon 2-30 isocyanate having an ethylenically unsaturated bond by known methods. Monomers having a carboxyl group; for example, methacrylic acid, acrylic acid, and 2-carboxyethyl (meth)acrylate. Monomers having a hydroxyl group; for example, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, etc. Monomers having an amide group; for example, acrylamide, monomers obtained by reacting an amine having 1 to 30 carbon atoms with a carboxylic acid having 2 to 30 carbon atoms having an ethylenically unsaturated bond (such as acrylic acid and methacrylic acid) by known methods. Monomers having a lactam structure; for example, N-vinyl-2-pyrrolidone.

[0070] Among these, monomers having a lactam structure are preferred, and N-vinyl-2-pyrrolidone having a five-membered ring lactam structure is more preferred. That is, crystalline vinyl resins preferably have monomer units having a lactam structure. Monomer units having a lactam structure are preferably represented by the following formula (L) (more preferably formula (L-1)). [ka] (In formulas (L) and (L-1), R2 represents a hydrogen atom or a methyl group.)

[0071] The crystalline vinyl resin more preferably has monomer units having a five-membered ring lactam structure. The crystalline vinyl resin is even more preferably having monomer units corresponding to N-vinyl-2-pyrrolidone. When a monomer unit having a five-membered ring lactam structure is included, a weak hydrogen bond is formed between the pyrrolidonyl group in the lactam structure and the carboxylic acid in the crystalline resin. Because the bond is weak, While there are no adverse effects on adhesion, a force is generated that moderately connects the interfaces of the crystal masses.

[0072] As mentioned above, the toner according to this disclosure has the characteristic of having small crystal clusters. However, as the diameter of the crystal clusters decreases, the total interface area increases, which may lead to the toner being affected by interface brittleness. By having monomer units with a five-membered ring lactam structure in the crystalline vinyl resin, the effects of interface brittleness can be suppressed while maintaining low-temperature fixability. As a result, it becomes easier to achieve both low-temperature fixability and better bending resistance, image loading performance, and abrasion resistance.

[0073] In crystalline vinyl resin, the content of monomer units having a lactam structure is preferably 2.0% by mass or more and 15.0% by mass or less.

[0074] The crystalline vinyl resin preferably has a weight-average molecular weight (Mw) of tetrahydrofuran (THF) soluble content measured by gel permeation chromatography (GPC) of 30,000 to 200,000. Having the Mw of the crystalline vinyl resin within the above range makes it easier to adjust the peak top temperature T1 of the endothermic peak P1 to an appropriate range. In addition, the separation characteristics with wax become appropriate, making it easier to achieve both low-temperature fixation and heat-resistant storage. A more preferred range for the Mw of the crystalline vinyl resin is 40,000 to 180,000, and even more preferably 60,000 to 150,000.

[0075] The toner may contain amorphous resin as a resin component other than crystalline vinyl resin. Examples of amorphous resins include vinyl resins, polyester resins, polyurethane resins, and epoxy resins, but vinyl resins and polyester resins are preferred. When the amorphous resin is a vinyl resin, for example, vinyl monomers that can be used with the aforementioned crystalline vinyl resins can be used. The (meth)acrylic acid ester for introducing the monomer unit (a) can also be used as long as the amorphous resin does not exhibit crystallinity.

[0076] Furthermore, so-called crosslinking agents, which have multiple vinyl groups per monomer, can also be used. Examples of crosslinking agents include the following: Diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol diacrylate, 1,6-hexanediol diacrylate, neopentyl glycol diacrylate, tripropylene glycol diacrylate, polypropylene glycol diacrylate, 2,2'-bis(4-(acryloxydiethoxy)phenyl)propane, trimethylolpropane triacrylate, tetramethylolmethane tetraacrylate, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate Tetraethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, 1,3-butylene glycol dimethacrylate, 1,6-hexanediol dimethacrylate, neopentyl glycol dimethacrylate, polypropylene glycol dimethacrylate, 2,2'-bis(4-(methacryloxydiethoxy)phenyl)propane, 2,2'-bis(4-(methacryloxypolyethoxy)phenyl)propane, trimethylolpropane trimethacrylate, tetramethylolmethane tetramethacrylate, divinylbenzene, divinylnaphthalene, divinyl ether, 4,4'-divinylbiphenyl, etc.

[0077] When using polyester resin as the amorphous resin, polyester resins obtained by the reaction of a divalent or higher polycarboxylic acid with a polyhydric alcohol can be used.

[0078] Examples of polycarboxylic acids include the following: Succulent acid, adipic acid, sebacic acid, phthalic acid, isophthalic acid, terephthalic acid, malonic acid , dibasic acids such as dodecenyl succinic acid, and their anhydrides or lower alkyl esters, as well as aliphatic unsaturated dicarboxylic acids such as maleic acid, fumaric acid, itaconic acid and citraconic acid. 1,2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid, and their anhydrides or lower alkyl esters. These may be used individually or in combination of two or more.

[0079] Examples of polyhydric alcohols include the following: Alkylene glycols (ethylene glycol, 1,2-propylene glycol, and 1,3-propylene glycol); alkylene ether glycols (polyethylene glycol and polypropylene glycol); alicyclic diols (1,4-cyclohexanedimethanol); bisphenols (bisphenol A); alkylene oxide (ethylene oxide and propylene oxide) adducts of alicyclic diols. The alkyl portions of alkylene glycols and alkylene ether glycols may be linear or branched. Furthermore, glycerin, trimethylolethane, trimethylolpropane, and pentaerythritol, etc. These may be used individually or in combination of two or more.

[0080] Furthermore, monohydric acids such as acetic acid and benzoic acid, and monohydric alcohols such as cyclohexanol and benzyl alcohol may be used as needed to adjust the acid value and hydroxyl value. For example, the transesterification method and the direct polycondensation method can be used individually or in combination as methods for producing polyester resin.

[0081] The toner particles may have a core-shell structure comprising a core particle having a resin and a shell covering the core particle. From the viewpoint of electrostatic stability, the resin forming the shell is preferably a vinyl resin or a polyester resin. More preferably, it is an amorphous polyester resin. The shell does not necessarily have to cover the entire core, and there may be parts where the core is exposed. As the vinyl resin and polyester resin constituting the shell, vinyl resins and polyester resins that can be used as crystalline vinyl resins and amorphous resins as described above can be used.

[0082] The toner particles may contain wax. The wax is at least one selected from the group consisting of hydrocarbon waxes and ester waxes. Using hydrocarbon waxes and / or ester waxes makes it easier to ensure effective release properties.

[0083] Examples of hydrocarbon waxes include the following: Aliphatic hydrocarbon waxes: low molecular weight polyethylene, low molecular weight polypropylene, low molecular weight olefin copolymer, Fischer-Tropsch wax, or waxes obtained by oxidation or acid addition of these.

[0084] Ester waxes only need to have at least one ester bond in each molecule, and either natural or synthetic ester waxes may be used. Examples of ester waxes include the following: Esters of monohydric alcohols and monocarboxylic acids, such as behenyl behenate, stearyl stearate, and palmityl palmitate; Esters of divalent carboxylic acids and monoalcohols, such as dibehenyl sebacate; Esters of dihydric alcohols such as ethylene glycol distearate and hexanediol dibehenate with monocarboxylic acids; Esters of trihydric alcohols such as glycerol tribehenate and monocarboxylic acids; Esters of tetrahydric alcohols such as pentaerythritol tetrastearate and pentaerythritol tetrapalmitate with monocarboxylic acids; Esters of hexahydritol alcohols such as dipentaerythritol hexastearate, dipentaerythritol hexapalmitate, and dipentaerythritol hexabéhenate with monocarboxylic acids; Esters of polyfunctional alcohols such as polyglycerin behenates and monocarboxylic acids; natural ester waxes such as carnauba wax and rice wax.

[0085] Among these, a bifunctional or more ester wax is preferred. In other words, it is preferable that the toner particles contain a bifunctional or more ester wax. In particular, ester waxes that are esters of an alcohol with a tetravalent or higher but no more than octavalent properties and an aliphatic monocarboxylic acid, or ester waxes that are esters of a carboxylic acid with a tetravalent or higher but no more than octavalent properties and an aliphatic monoalcohol are more preferred. When toner particles contain these ester waxes, their compatibility with the crystalline vinyl resin during fixing is reduced, which improves release properties during low-temperature fixing and enhances low-temperature fixing performance. Furthermore, by appropriately controlling the content ratio of the monomer unit (a) in the resin component, it becomes easier to partially form a eutectic state, which makes peak splitting in differential scanning calorimetry easier and further improves bending resistance.

[0086] Furthermore, it is even more preferable to use the following ester waxes. Esters of tetrahydric alcohols such as pentaerythritol tetrastearate, pentaerythritol tetrapalmitate, and pentaerythritol tetrabehenate with monocarboxylic acids; esters of hexahydric alcohols such as dipentaerythritol hexastearate, dipentaerythritol hexapalmitate, and dipentaerythritol hexabehenate with monocarboxylic acids; and esters of octahydric alcohols such as tripentaerythritol octastearate, tripentaerythritol octapalmitate, and tripentaerythritol octabehenate with monocarboxylic acids.

[0087] The wax content in the toner particles is preferably 1.0% by mass or more and 30.0% by mass or less, more preferably 2.0% by mass or more and 25.0% by mass or less. Having the wax content in the toner particles within this range makes it easier to ensure release properties during fixing. The melting point of the wax is preferably between 60°C and 120°C. A melting point within this range allows the wax to melt during fixing and easily seep onto the toner particle surface, thus facilitating the release properties of the wax. More preferably, the melting point of the wax is between 70°C and 100°C.

[0088] Toner particles may contain colorants. Examples of colorants include known organic pigments, organic dyes, inorganic pigments, carbon black as a black colorant, and magnetic particles. Other colorants conventionally used in toners may also be used.

[0089] Examples of yellow colorants include: condensed azo compounds, isoindolinone compounds, anthraquinone compounds, azo metal complexes, methine compounds, and allylamide compounds. Among these, CI Pigment Yellow 12, 13, 14, 15, 17, 62, 74, 83, 93, 94, 95, 109, 110, 111, 128, 129, 147, 155, 168, and 180 are preferred.

[0090] Examples of magenta colorants include: condensed azo compounds, diketopyrrolopyrrole compounds, anthraquinone compounds, quinacridone compounds, basic dye lake compounds, naphthol compounds, benzimidazolon compounds, thioindigo compounds, and perylene compounds. Among these, CI Pigment Red 2, 3, 5, 6, 7, 23, 48:2, 48:3, 48:4, 57:1, 81:1, 122, 144, 146, 166, 169, 177, 184, 185, 202, 206, 220, 221, and 254 are preferably used. It can be done.

[0091] Examples of cyanide colorants include: copper phthalocyanine compounds and their derivatives, anthraquinone compounds, and basic dye lake compounds. Among these, CI pigment blues 1, 7, 15, 15:1, 15:2, 15:3, 15:4, 60, 62, and 66 are preferably used. The colorants are selected based on their hue angle, saturation, brightness, lightfastness, OHP transparency, and dispersibility in toner.

[0092] The colorant content in the toner particles is preferably 1.0% by mass or more and 20.0% by mass or less. When magnetic particles are used as the colorant, their content is preferably 30.0% by mass or more and 60.0% by mass or less, based on the mass of the toner particles.

[0093] Toner particles may contain a charge control agent. Alternatively, a charge control agent may be added externally to the toner particles. Using a charge control agent stabilizes the charge characteristics and allows for optimal control of the amount of triboelectric charge according to the developing system. As a charge control agent, one that has a fast charging speed and can stably maintain a constant amount of charge is preferred.

[0094] Examples of charge control agents that control the toner's load charge include the following: Organometallic compounds and chelate compounds are effective, and examples include monoazo metal compounds, acetylacetone metal compounds, aromatic oxycarboxylic acids, aromatic dicarboxylic acids, oxycarboxylic acids, and dicarboxylic acid-based metal compounds. Examples of substances that control the toner's positive charge include: nigrosine, quaternary ammonium salts, metal salts of higher fatty acids, diorganostin borates, guanidine compounds, and imidazole compounds.

[0095] The content of the charge control agent in the toner particles is preferably 0.01% by mass or more and 20.0% by mass or less, and more preferably 0.5% by mass or more and 10.0% by mass or less.

[0096] The toner particles can be used as toner as is, or, if necessary, external additives can be mixed in and attached to the surface of the toner particles to create toner. Examples of external additives include inorganic fine particles selected from the group consisting of silica fine particles, alumina fine particles, and titania fine particles, or composite oxides thereof. Examples of composite oxides include silica-aluminum fine particles and strontium titanate fine particles. The content of the external additive is preferably 0.01 parts by mass or more and 8.0 parts by mass or less per 100 parts by mass of toner particles, and more preferably 0.1 parts by mass or more and 4.0 parts by mass or less.

[0097] Toner particles can be manufactured by methods such as suspension polymerization, emulsification and agglutination, dissolution and suspension, and pulverization. It is preferable to manufacture toner particles by suspension polymerization. The suspension polymerization method will be described in detail below.

[0098] For example, a pre-synthesized crystalline vinyl resin is added to a mixture of polymerizable monomers that produce resin components such as amorphous resins. If necessary, other materials such as colorants, waxes, and charge control agents are added and uniformly dissolved or dispersed to prepare a polymerizable monomer composition. Subsequently, the polymerizable monomer composition is dispersed in an aqueous medium using a stirrer or the like to prepare suspended particles of the polymerizable monomer composition. Then, the polymerizable monomers contained in the particles are polymerized with an initiator or the like, and the resulting toner particle dispersion is cooled to obtain a toner particle dispersion.

[0099] The degree of crystallinity of crystalline vinyl resin can be controlled by varying the cooling rate after polymerization. If the cooling rate is fast, the molecular motion stops before the alkyl groups in the side chains of the crystalline resin can orient regularly, resulting in a decrease in the degree of crystallinity.

[0100] The above cooling rate is preferably adjusted as appropriate depending on the type of monomer unit to be polymerized. For example, when vinyl polymerization is carried out using the above-mentioned alkyl group-containing (meth)acrylic acid ester as a polymerizable monomer, it is preferable to set the cooling rate after polymerization to a range of 0.030 to 2.500 °C / s. It is more preferable to set the cooling rate to 0.050 to 2.000 °C / s, and more preferably to 0.070 to 1.000 °C / s.

[0101] After the cooling process described above, the toner particle dispersion may be subjected to an annealing step, if necessary, in which it is maintained at a constant temperature. By thoroughly performing the annealing step, the molecular motion of polymers with misaligned orientations can be promoted, thereby advancing crystallization.

[0102] In the annealing process, the holding time and temperature of the toner particle dispersion are preferably adjusted as appropriate depending on the type of monomer unit to be polymerized. For example, when vinyl polymerization is carried out using the above-mentioned alkyl group-containing (meth)acrylic acid ester as a polymerizable monomer, the holding temperature is preferably 30 to 60°C, more preferably 35 to 55°C, and even more preferably 40 to 50°C. The holding time is preferably 0.5 to 15.0 hours, more preferably 3.0 to 10.0 hours, and even more preferably 5.0 to 10.0 hours.

[0103] After polymerization is complete, the toner particles are filtered, washed, and dried, and external additives are added as needed to obtain the toner. In other words, the toner manufacturing method preferably comprises the steps of: obtaining a polymerizable monomer composition containing a crystalline vinyl resin, an amorphous resin, and optionally a colorant, wax, etc.; dispersing the polymerizable monomer composition in an aqueous medium and polymerizing it to obtain a toner particle dispersion; cooling the toner particle dispersion at a cooling rate of 0.030 to 2.500 °C / s; and annealing the cooled toner particle dispersion at 30 to 60 °C for 30 minutes or more.

[0104] When the crystalline vinyl resin is a vinyl-based resin, it can be manufactured using the above-mentioned monomer units and polymerization initiators. Examples of polymerization initiators include the following: Azo or diazo polymerization initiators such as 2,2'-azobis-(2,4-dimethylvaleronitrile), 2,2'-azobisisobutyronitrile, 1,1'-azobis(cyclohexane-1-carbonnitrile), 2,2'-azobis-4-methoxy-2,4-dimethylvaleronitrile, and azobisisobutyronitrile; and peroxide polymerization initiators such as benzoyl peroxide, t-butyl peroxy 2-ethylhexanoate, t-butyl peroxypivalate, t-butyl peroxyisobutylate, t-butyl peroxyoctoate, t-butyl peroxyneodecanoate, methyl ethyl ketone peroxide, diisopropyl peroxycarbonate, cumenehydroperoxide, 2,4-dichlorobenzoyl peroxide, and lauroyl peroxide.

[0105] Among the above, peroxide-based polymerization initiators are preferred as they readily cause hydrogen abstraction reactions. Of these, initiators such as t-butyl peroxy 2-ethyl hexanoate, t-butyl peroxypivalate, t-butyl peroxyisobutyrate, t-butyl peroxyoctoate, and t-butyl peroxyneodecanoate are more preferably used. In addition, known chain transfer agents or polymerization inhibitors may be used.

[0106] The aqueous medium may contain an inorganic or organic dispersion stabilizer. Known dispersion stabilizers can be used as the dispersion stabilizer. Examples of inorganic dispersion stabilizers include phosphates such as hydroxyapatite, tricalcium phosphate, dicalcium phosphate, magnesium phosphate, aluminum phosphate, and zinc phosphate; carbonates such as calcium carbonate and magnesium carbonate; metal hydroxides such as calcium hydroxide, magnesium hydroxide, and aluminum hydroxide; sulfates such as calcium sulfate and barium sulfate; calcium metasilicate; bentonite; silica; and alumina. Examples of organic dispersion stabilizers include polyvinyl alcohol, gelatin, methylcellulose, methylhydroxypropylcellulose, ethylcellulose, sodium salts of carboxymethylcellulose, polyacrylic acid and its salts, and starch.

[0107] When using an inorganic compound as a dispersion stabilizer, commercially available products may be used as is, but in order to obtain finer particles, the inorganic compound may be generated in an aqueous medium before use. For example, in the case of calcium phosphate such as hydroxyapatite or tricalcium phosphate, it is best to mix the phosphate aqueous solution with the calcium salt aqueous solution under high stirring.

[0108] The aqueous medium may contain a surfactant. Known surfactants can be used as the surfactant. Examples include anionic surfactants such as sodium dodecylbenzene sulfate and sodium oleate; cationic surfactants; amphoteric surfactants; and nonionic surfactants.

[0109] Toner particles may also be manufactured by a pulverization method. For example, a pre-synthesized crystalline vinyl resin is mixed with resin components such as amorphous resin and, if necessary, colorants, release agents, etc., and then melt-kneaded. After the resulting melt-kneaded material is cooled, it is pulverized, and if necessary, toner particles can be obtained by performing processes such as classification. Known equipment can be used for melt-kneading and pulverization.

[0110] In other words, the toner manufacturing method may include a step of melting and kneading raw materials containing crystalline vinyl resin, amorphous resin, and optionally colorants, waxes, etc., and a step of pulverizing the resulting molten mixture to obtain toner particles.

[0111] In the case of the melt-mixing method, the following methods can be used to satisfy all of equations (1) to (3). For example, by controlling the type of crystalline vinyl resin used and the amount of additives other than binder resins such as wax as described above, toner that satisfies all of equations (1) to (3) can be obtained. Another method is to control the cooling rate after obtaining the molten mixture in the toner particle manufacturing process to within the above range. Furthermore, similar to the case of manufacturing toner by suspension polymerization, annealing may be performed after the above cooling, and methods such as controlling the annealing holding temperature and time to within the above range can also be used.

[0112] The following describes the calculation and measurement methods for various physical properties of toner and toner materials.

[0113] <Separation of toner particles from toner> The toner particles obtained by separating the toner particles from the external additive using the following method can be used for each analysis. Add 160g of sucrose (manufactured by Kishida Chemical) to 100mL of deionized water and dissolve it while heating in a water bath to prepare a sucrose aqueous solution. Place 31g of the sucrose aqueous solution and 6mL of Contaminon N (nonionic surfactant, anionic surfactant, organic bilder) into a centrifuge tube. Prepare a dispersion by adding a 10% by mass aqueous solution of a pH 7 neutral detergent for cleaning precision measuring instruments (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.). Add 1 g of toner to this dispersion and break up any clumps of toner with a spatula or similar tool. The centrifugation tube is placed in an Iwaki Sangyo Co., Ltd. "KM Shaker" (model: V.SX) and shaken for 20 minutes at a rate of 350 strokes per minute. After shaking, the solution is transferred to a 50 mL glass tube for the swing rotor and centrifuged in a centrifuge at 3500 rpm for 30 minutes. In the glass tube after centrifugation, toner particles are present in the uppermost layer, while external additives such as silica microparticles are present in the lower aqueous solution layer. The toner particles from the upper layer are collected, filtered, and washed with 2 liters of deionized water heated to 40°C. The washed toner particles are then removed.

[0114] <Method for measuring endothermic peak temperature and heat absorption amount> The endothermic peak temperature (melting point) and heat absorption of toner, resin, or wax are measured using a DSC Q2000 (TA Instruments) under the following conditions. Heating rate: 10℃ / min Measurement start temperature: 20℃ Measurement end temperature: 180℃ The temperature correction for the device's detection unit uses the melting points of indium and zinc, while the heat of fusion of indium is used for heat quantity correction. Specifically, 5 mg of the sample is accurately weighed, placed in an aluminum pan, and differential scanning calorimetry is performed. An empty silver pan is used as a reference.

[0115] The above sample is heated from 20°C to 180°C at a rate of 10°C / min to obtain the DSC endothermic curve during heating process 1. Then, it is held at 180°C for 10 minutes, and cooled from 180°C to 20°C at a rate of 10°C / min. Furthermore, it is held at 20°C for 10 minutes, and then heated again from 20°C to 180°C at a rate of 10°C / min to obtain the DSC endothermic curve during heating process 2. The temperature at which the differential curve of the obtained DSC endothermic curve shows a minimum value is defined as the peak-top temperature, and the peak-top temperature and heat absorption amount for each endothermic peak are calculated. The peak top temperature and heat absorption amount for each endothermic peak are calculated using the DSC endothermic curve analysis software "Universal Analysis 2000" (manufactured by TA Instruments Co., Ltd.).

[0116] In calculating the amount of heat absorbed, the baseline is defined as the line from the point where the derivative of the lowest temperature endothermic peak below the endothermic temperature becomes zero, to the point where the derivative of the highest temperature endothermic peak above the endothermic temperature becomes zero. In this disclosure, "endothermic peak originating from crystalline vinyl resin" refers to the endothermic peak obtained by measuring the endothermic peak position of a material other than crystalline resin, such as wax, that exhibits a melting point, and excluding the endothermic peak originating from the melting point of that material alone, when the toner contains such materials. Furthermore, an endothermic peak originating from the eutectic state between crystalline vinyl resin and other materials is also defined as an "endothermic peak originating from crystalline vinyl resin."

[0117] Furthermore, if a stable DSC endothermic curve cannot be obtained due to measurement accuracy limitations, minute peaks resulting from fluctuations in the apparatus will be excluded from the counting of endothermic peaks in this disclosure. If it is unclear whether the phenomenon is due to measurement accuracy limitations, peaks with an endothermic value of 0.1 J / g or more will be included in the counting of endothermic peaks in this disclosure. In heating process 1, a gentle peak originating from the relaxation of the crystalline vinyl resin may be present on the DSC endothermic curve. In this case, the peak originating from relaxation is identified by comparing it with the DSC endothermic curve in heating process 2, where the relaxation-derived peak disappears, and is excluded from the count of endothermic peaks.

[0118] When endothermic peaks originating from crystalline vinyl resin partially overlap, the above DSC endothermic curve The peaks are divided using linear analysis software, and then the amount of heat absorbed for each peak is calculated. When dividing, the DSC endothermic curve between the peak tops of each overlapping endothermic peak is divided vertically from the point of maximum value toward the baseline.

[0119] In DSC measurements using toner as a sample, if the endothermic peak originating from crystalline vinyl resin does not overlap with other endothermic peaks such as wax, the obtained endothermic peak is considered to be the "endothermic peak originating from crystalline vinyl resin."

[0120] On the other hand, if the endothermic peaks of other components such as wax overlap with the endothermic peaks derived from the crystalline vinyl resin, it is necessary to separate the endothermic peaks derived from the wax. For example, the endothermic peaks derived from the wax can be separated and the endothermic peaks derived from the crystalline vinyl resin can be obtained by the following method. First, DSC measurements of the wax alone are performed separately using the method described above to determine its endothermic properties. Next, the wax content in the toner is determined. The wax content in the toner can be measured using known structural analysis methods. Subsequently, the endothermic peak attributable to the wax is determined from the wax content in the toner, and by subtracting this from the peak attributable to the crystalline vinyl resin, the endothermic peak attributable to the crystalline vinyl resin can be identified.

[0121] <Method for separating crystalline vinyl resin from toner particles> The separation of crystalline vinyl resin from toner can be achieved by known methods. One example is shown below. Gradient polymer LC is used as a method for separating resin components from toner. This analysis allows for separation based on the polarity of the resin in the binder resin, regardless of molecular weight. First, the toner is dissolved in chloroform. The sample is prepared in chloroform to a sample concentration of 0.1% by mass, and the solution is filtered through a 0.45 μm PTFE filter before being used for measurement.

[0122] The measurement conditions for gradient polymer LC are shown below. Equipment: UlTIMATE3000 (manufactured by Thermo Fisher Scientific) Mobile phase: A. Chloroform (HPLC), B. Acetonitrile (HPLC) Gradient: 2 min (A / B=0 / 100) → 25 min (A / B=100 / 0) (Note that the gradient of the mobile phase change should be a straight line.) Flow rate: 1.0mL / min Injection: 0.1 mass% x 20 μL Column: Tosoh TSKgel ODS (4.6mmφ x 150mm x 5μm) Column temperature: 40℃ Detector: Corona Charged Particle Detector (Corona-CAD) (manufactured by Thermo Fisher Scientific) The time-intensity graph obtained from the above measurement allows for the separation of the resin component into two peaks depending on its polarity. Subsequently, by repeating the above measurement and separating the samples at the time of the trough of each peak, it is possible to separate the resin into two types. DSC measurements are performed on the separated resins, and the resin with a melting point peak is identified as the crystalline resin.

[0123] Furthermore, if the toner contains wax, it is necessary to separate the wax from the toner. Wax separation is performed by recycling HPLC, separating components with a molecular weight of 2000 or less as wax. The measurement method is shown below. First, prepare a chloroform solution of toner using the method described above. Then, use the obtained solution to create a solvent-resistant membrane filter "MyShoriDisk" (Tohsoh) with a pore diameter of 0.2 μm. The sample solution is obtained by filtering it using a filter (manufactured by company 1). The sample solution is adjusted so that the concentration of the chloroform-soluble component is 1.0% by mass.

[0124] This sample solution will be used for measurement under the following conditions. ·Equipment: LC-Sakura NEXT (manufactured by Nippon Analytical Industry Co., Ltd.) • Columns: JAIGEL2H, 4H (manufactured by Nippon Analytical Engineering Co., Ltd.) • Eluent: Chloroform ·Flow rate: 10.0ml / min Oven temperature: 40.0℃ • Sample injection volume: 1.0 ml When calculating the molecular weight of the sample, a molecular weight calibration curve prepared using a standard polystyrene resin (e.g., trade names "TSK Standard Polystyrene F-850, F-450, F-288, F-128, F-80, F-40, F-20, F-10, F-4, F-2, F-1, A-5000, A-2500, A-1000, A-500", manufactured by Tosoh Corporation) is used. From the molecular weight curve thus obtained, components with a molecular weight of 2000 or less are repeatedly fractionated to remove wax from the toner.

[0125] <Method for Measuring the Chain Length of the Alkyl Group of the Monomer Unit in the Crystalline Vinyl Resin> The measurement of the chain length of the monomer unit in the crystalline vinyl resin is 1 performed by 1H-NMR under the following conditions. As the measurement sample, the crystalline vinyl resin fractionated by the above method can be used. Measuring device: FT NMR device JNM-EX400 (manufactured by JEOL Ltd.) Measuring frequency: 400 MHz Pulse condition: 5.0 μs Frequency range: 10500 Hz Number of integrations: 64 times Measuring temperature: 30 °C Sample: 50 mg of the measurement sample is placed in a sample tube with an inner diameter of 5 mm, and deuterated chloroform (CDCl3) is added as a solvent, and this is dissolved in a constant temperature bath at 40 °C for preparation.

[0126] The obtained 1 1H-NMR chart is analyzed to identify the structure of each monomer unit. The chain length (number of carbon atoms m) of the alkyl group of the monomer unit can be 1 calculated from the integration ratio of the proton peaks in the 1H-NMR chart. In addition, when a polymerizable monomer that does not contain a hydrogen atom in components other than the vinyl group is used, 13 13C-NMR is used to measure the nuclei as 13 13C, and the measurement is performed in single pulse mode, 1The same calculation is performed using 1H-NMR. In addition, infrared absorption spectroscopy (IR) and gas chromatography-mass spectrometry (GC-MS) results may be used as needed.

[0127] <Method for measuring the content ratio of crystalline vinyl resin in resin components> In the method for separating crystalline vinyl resin from toner particles as described above, the proportion of crystalline vinyl resin in the toner is calculated based on the mass of the toner before dissolving it in chloroform and the mass of the crystalline vinyl resin separated from the toner particles.

[0128] <Method for measuring the content ratio of monomer units (a) in resin components> The measurement of the content ratio of monomer units (a) in the resin components is performed as follows: 1 The procedure is performed using H-NMR under the following conditions. Measuring device: FT NMR device JNM-EX400 (manufactured by JEOL Ltd.) Measurement frequency: 400MHz Pulse condition: 5.0 μs Frequency range: 10500Hz Total number of times: 64 Measurement temperature: 30℃ Sample: Prepared as follows 50 mg of the sample to be measured is placed in a sample tube with an inner diameter of 5 mm, deuterated chloroform (CDCl3) is added as a solvent, and the mixture is dissolved in a constant temperature bath at 40°C to prepare the sample. As the sample to be measured, crystalline vinyl resin separated from toner particles by the method described above can be used. obtained 1 The H-NMR chart is analyzed to identify the structure of each unit.

[0129] obtained 1 In the H-NMR chart, a peak independent of the peaks attributed to the monomer unit (a) is selected from among the peaks attributed to the components of the other units, and the integral value S1 of this peak is calculated. The integral values ​​are calculated similarly for the other units contained in the resin. When the resin component consists of monomer unit (a) and one other unit, the content ratio of monomer unit (a) is determined as follows using the integral value S1 and the integral value S2 of the peak of the other unit. Note that n1 and n2 are the number of hydrogen atoms in the constituent element to which the peak of interest belongs for each part. The content of monomer unit (a) (mol %) = {(S1 / n1) / ((S1 / n1)+(S2 / n2))} × 100 Similarly, even if there are two or more other units, the content ratio of monomer unit (a) can be calculated (using S3···Sx, n3···nx).

[0130] If monomers are used in which the components other than the vinyl group do not contain hydrogen atoms, 13 The atomic nuclei were measured using C-NMR. 13 Let C be used, and the measurement will be performed in single-pulse mode. 1 The same calculation can be performed using 1H-NMR. The percentage (mol%) of each unit calculated by the above method is multiplied by the molecular weight of each unit to convert the content of each unit into mass%.

[0131] Furthermore, when measuring NMR using toner as a sample, peaks from waxes and resins other than crystalline vinyl resin may overlap, preventing the observation of independent peaks. This can make it impossible to calculate the content ratio of each monomer unit in the crystalline vinyl resin. In such cases, resin A' can be produced by performing the same manufacturing process without using waxes or other resins, and then analyzed as if it were the crystalline vinyl resin.

[0132] <Method for measuring the weight-average molecular weight (Mw) of resins> The weight-average molecular weight (Mw) of the resin is measured by gel permeation chromatography (GPC) as follows: First, the sample is dissolved in tetrahydrofuran (THF) at room temperature for 24 hours. Then, the resulting solution is filtered through a solvent-resistant membrane filter, "Myshoridisk" (manufactured by Tosoh Corporation), with a pore diameter of 0.2 μm to obtain the sample solution. The sample solution is adjusted so that the concentration of components soluble in THF is 0.8% by mass. This sample solution is then measured under the following conditions. Equipment: HLC8120GPC (Detector: RI) (Manufactured by Tosoh Corporation) Columns: Shodex KF-801, 802, 803, 804, 805, 806, 807 (7 columns, manufactured by Showa Denko) Eluent: Tetrahydrofuran (THF) Flow rate: 1.0mL / min Oven temperature: 40.0℃ Sample injection volume: 0.10 mL When calculating the weight-average molecular weight of the sample, a standard polystyrene resin (for example, product name " A molecular weight calibration curve created using TSK Standard Polystyrene F-850, F-450, F-288, F-128, F-80, F-40, F-20, F-10, F-4, F-2, F-1, A-5000, A-2500, A-1000, A-500 (manufactured by Tosoh Corporation) will be used. [Examples]

[0133] The present disclosure will be described in detail below with reference to examples, but these examples are not intended to limit the present disclosure in any way. In the following formulations, "parts" refers to "parts by mass" unless otherwise specified.

[0134] (Preparation of resin A1) The following materials were added to a reaction vessel equipped with a reflux condenser, a stirrer, a thermometer, and a nitrogen inlet tube under a nitrogen atmosphere. • Toluene 100.0 parts • Monomer composition 100.0 parts (The monomer composition used was a mixture of the following monomers in the proportions shown below.) (Behenyl acrylate 60.0 parts) (Styrene 25.0 parts) (Methacrylonitrile 5.0 parts) (·N-vinyl-2-pyrrolidone 10.0 parts) • Polymerization initiator: t-butyl peroxypivalate (manufactured by NOF Corporation: Perbutyl PV) 2.0 parts by mass The materials were heated to 70°C in a reaction vessel while being stirred at 200 rpm, and a polymerization reaction was carried out for 12 hours to obtain a solution in which the polymer in the monomer composition was dissolved in toluene. Subsequently, the solution was cooled to 25°C, and then added to 1000.0 parts methanol while stirring to precipitate the methanol-insoluble components. The obtained methanol-insoluble components were filtered off, washed with methanol, and then vacuum-dried at 40°C for 24 hours to obtain resin A1.

[0135] When resin A1 was analyzed by NMR using the method described above, and the calculated percentage (mol%) of each unit was converted to mass%, resin A1 contained 60.0 mass% of monomer units polymerized from behenyl acrylate, 25.0 mass% of monomer units polymerized from styrene, 5.0 mass% of monomer units polymerized from methacrylonitrile, and 10.0 mass% of monomer units polymerized from N-vinyl-2-pyrrolidone.

[0136] (Preparation of resin B1) The following materials were added to a reaction vessel equipped with a reflux condenser, a stirrer, a thermometer, and a nitrogen inlet tube under a nitrogen atmosphere. • Toluene 100.0 parts Behenyl acrylate 100.0 parts • Polymerization initiator: t-butyl peroxypivalate (manufactured by NOF Corporation: Perbutyl PV) 2.0 parts by mass The materials were heated to 70°C in a reaction vessel while being stirred at 200 rpm, and a polymerization reaction was carried out for 12 hours to obtain a solution in which the polymer in the monomer composition was dissolved in toluene. Subsequently, the solution was cooled to 25°C, and then added to 1000.0 parts methanol while stirring to precipitate the methanol-insoluble components. The obtained methanol-insoluble components were filtered off, washed with methanol, and then vacuum-dried at 40°C for 24 hours to obtain resin B1. When resin B1 was analyzed by NMR using the method described above, and the calculated percentage (mol%) of each unit was converted to mass%, it was found that resin B1 contained 100.0 mass% monomer units polymerized from behenyl acrylate.

[0137] (Preparation of resin C1) The following materials were added to an autoclave equipped with a vacuum device, a water separator, a nitrogen gas introduction device, a temperature measuring device, and a stirring device. Terephthalic acid 25.3 parts • Bisphenol A-propylene oxide 2 molar adduct 74.7 parts • Potassium titanium oxalate (catalyst) 0.02 parts Next, the reaction was carried out under a nitrogen atmosphere and atmospheric pressure at 220°C for 5 hours, and then under reduced pressure at 220°C for 3 hours. After cooling, the mixture was pulverized to obtain resin C1.

[0138] (Preparation of resins A2 to A20) Crystalline resins A2 to A20 were prepared in the same manner as resin A1, except that the type and amount of monomers used were changed as shown in Table 1. When resins A2 to A20 were analyzed by NMR using the method described above, monomer units polymerized from each monomer were found to be present in the same proportions as the monomers used.

[0139] (Preparation of resins B2 to B10) Crystalline resins B2 to B10 were prepared in the same manner as resin B1, except that the type and amount of monomers used and the amount of polymerization initiator added were changed as shown in Table 2. When resins B2 to B10 were analyzed by NMR using the method described above, the monomer units polymerized from each monomer were found to be present in the same proportions as the monomers used.

[0140] [Table 1] In the table, Mw represents the weight-average molecular weight (Mw) of tetrahydrofuran (THF) soluble content as measured by gel permeation chromatography (GPC).

[0141] [Table 2]

[0142] <Example 1> [Toner manufacturing by suspension polymerization method] (Manufacturing of toner particles 1) A mixture of the following materials was prepared. • Styrene 45.0 parts • n-butyl acrylate 15.0 parts Pigment blue 15:3 (coloring agent) 6.5 parts The mixture was placed in an attritor (manufactured by Nippon Coke Industries Co., Ltd.) and dispersed using 5 mm diameter zirconia beads at 200 rpm for 2 hours to obtain a raw material dispersion.

[0143] Meanwhile, 735.0 parts of deionized water and 16.0 parts of trisodium phosphate (dodecahydrate) were added to a container equipped with a high-speed stirring device homomixer (manufactured by Primix Co., Ltd.) and a thermometer, and the temperature was raised to 60°C while stirring at 12,000 rpm. Then, an aqueous calcium chloride solution, prepared by dissolving 9.0 parts of calcium chloride (dihydrate) in 65.0 parts of deionized water, was added, and the mixture was stirred at 12,000 rpm for 30 minutes while maintaining the temperature at 60°C. Then, 10% hydrochloric acid was added to adjust the pH to 6.0, and an aqueous medium in which an inorganic dispersion stabilizer containing hydroxyapatite was dispersed in water was obtained.

[0144] Next, the raw material dispersion was transferred to a container equipped with a stirrer and a thermometer, and heated to 60°C while stirring at 100 rpm. The following materials were then added, and the mixture was stirred at 100 rpm for 30 minutes while maintaining a temperature of 60°C. • Resin A1 30.0 parts ·Resin B1 10.0 parts ·Resin C1 4.0 parts • DP18 (Dipentaerythritol stearate wax, melting point 79°C, manufactured by Nisshin Oillio Group Ltd.) 9.0 parts • HDDA (Hexanediol diacrylate) 0.1 part Subsequently, 8.0 parts of t-butyl peroxypivalate (manufactured by NOF Corporation: Perbutyl PV) were added as a polymerization initiator and stirred for a further minute. The mixture was then added to an aqueous medium being stirred at 12,000 rpm using the high-speed stirring device. Stirring was continued at 12,000 rpm for 20 minutes while maintaining a temperature of 60°C using the high-speed stirring device to obtain a granulated liquid.

[0145] The granulated liquid was transferred to a reaction vessel equipped with a reflux condenser, stirrer, thermometer, and nitrogen inlet tube, and heated to 75°C while stirring at 150 rpm under a nitrogen atmosphere. The temperature was not maintained at 75°C. The polymerization reaction was carried out at 150 rpm for 6 hours to obtain a toner particle dispersion. The obtained toner particle dispersion was cooled to 48°C at a cooling rate of 0.083°C / s while stirring at 150 rpm, and then annealed for 8 hours while maintaining the temperature at 48°C. After that, while maintaining stirring, dilute hydrochloric acid was added until the pH reached 1.5 to dissolve the dispersion stabilizer. The solid components were filtered off, thoroughly washed with deionized water, and then vacuum dried at 30°C for 24 hours to obtain toner particle 1.

[0146] (Preparation of Toner 1) For every 1:98.0 parts of toner particles, an external additive is provided: silica microparticles (hydrophobically treated with hexamethyldisilazane, primary particle number average particle size: 10 nm, BET specific surface area: 170 m²). 22.0 parts of ( / g) were added and mixed for 15 minutes at 3000 rpm using a Henschel mixer (manufactured by Nippon Coke Industries Co., Ltd.) to obtain toner 1 containing resin A1 and resin B1. The physical properties of the obtained toner 1 are shown in Table 4, and the evaluation results are shown in Table 5.

[0147] <Examples 2-29> In Example 1, toner particles 2 to 29 were obtained in the same manner as in Example 1, except that the type and amount of resin used, the type and amount of wax added, the cooling rate after polymerization, the annealing temperature, and the annealing time were changed as shown in Table 3. Furthermore, toners 2-29 were obtained by performing the same external additive procedure as in Example 1. The physical properties of the toners are shown in Table 4, and the evaluation results are shown in Table 5.

[0148] <Example 30> [Toner manufacturing using the grinding method] (Preparation of amorphous vinyl resin 1) The following materials were added to a reaction vessel equipped with a reflux condenser, stirrer, thermometer, and nitrogen inlet tube under a nitrogen atmosphere. • Solvent (toluene) 100.0 parts • Styrene 45.0 parts • n-butyl acrylate 15.0 parts • HDDA (Hexanediol diacrylate) 0.1 part • Polymerization initiator: t-butyl peroxypivalate (manufactured by NOF Corporation: Perbutyl PV) 5.0 parts The reaction vessel was heated to 70°C while stirring at 200 rpm, and the polymerization reaction was carried out for 12 hours to obtain a solution in which the monomer polymer was dissolved in toluene. Subsequently, the solution was cooled to 25°C, and then added to 1000.0 parts methanol while stirring to precipitate the methanol-insoluble components. The obtained methanol-insoluble components were filtered off, washed with methanol, and then vacuum-dried at 40°C for 24 hours to obtain amorphous vinyl resin 1.

[0149] Amorphous vinyl resin 1 was analyzed by NMR using the method described above, and when the mole percentage was converted to mass percentage, it was found that monomer units formed by the polymerization of each monomer were present in the same proportions as the monomers used.

[0150] (Manufacturing of toner particles 30) Amorphous vinyl resin 1: 60.0 parts • Resin A1: 30.0 parts ·Resin B1: 10.0 parts ·Resin C1: 4.0 parts • DP18 (Dipentaerythritol stearate wax, melting point 79°C, manufactured by Nisshin Oillio Group Ltd.): 9.0 parts Pigment blue 15:3 (coloring agent): 6.5 parts The above materials were mixed using a Henschel mixer (FM-75 model, manufactured by Mitsui Mining Co., Ltd.) at a rotation speed of 1500 rpm for a rotation time of 5 min, and then kneaded in a twin-screw kneader (PCM-30 model, manufactured by Ikegai Co., Ltd.) set to a temperature of 130°C. The resulting kneaded material was cooled and coarsely ground to a size of 1 mm or less using a hammer mill to obtain coarse material. The obtained coarse material was finely ground using a mechanical crusher (T-250, manufactured by Turbo Industries Co., Ltd.). Further classification was performed using a Faculty (F-300, manufactured by Hosokawa Micron Corporation) to obtain toner particles 30. The operating conditions were a classification rotor speed of 11,000 rpm and a dispersion rotor speed of 7,200 rpm.

[0151] (Manufacturing of Toner 30) Toner 30 was obtained by adding toner particles 30 in the same manner as in Example 1. The physical properties of the toner are shown in Table 4, and the evaluation results are shown in Table 5.

[0152] <Comparative Examples 1-4> Comparative toner particles 1 to 4 were obtained in the same manner as in Example 1, except that the type and amount of resin used, the type and amount of wax added, the cooling rate after polymerization, the annealing temperature, and the annealing time were changed as shown in Table 3. Furthermore, comparative toners 1-4 were obtained by performing the same external additive procedure as in Example 1. The physical properties of the toners are shown in Table 4, and the evaluation results are shown in Table 5.

[0153] <Comparative Example 5> (Preparation of comparative amorphous vinyl resin 1) The following materials were added to a reaction vessel equipped with a reflux condenser, stirrer, thermometer, and nitrogen inlet tube under a nitrogen atmosphere. • Solvent (toluene) 100.0 parts • Styrene 64.0 parts Behenyl acrylate 28.0 parts • Acrylonitrile 5.0 parts • Methacrylic acid 3.0 parts • Polymerization initiator: t-butyl peroxypivalate (manufactured by NOF Corporation: Perbutyl PV) 5.0 parts The reaction vessel was heated to 70°C while stirring at 200 rpm, and the polymerization reaction was carried out for 12 hours to obtain a solution in which the monomer polymer was dissolved in toluene. Subsequently, the solution was cooled to 25°C, and then added to 1000.0 parts methanol while stirring to precipitate the methanol-insoluble components. The obtained methanol-insoluble components were filtered off, washed with methanol, and then vacuum-dried at 40°C for 24 hours to obtain comparative amorphous vinyl resin 1. Comparative amorphous vinyl resin 1 was analyzed by NMR using the method described above. When the molecular percentages were converted to mass percentages, comparative amorphous vinyl resin 1 contained 64.0 mass% of monomer units polymerized from styrene, 28.0 mass% of monomer units polymerized from behenyl acrylate, 5.0 mass% of monomer units polymerized from acrylonitrile, and 3.0 mass% of monomer units polymerized from methacrylic acid.

[0154] <Manufacturing example of comparative toner 5> [Toner manufacturing by suspension polymerization method] (Preparation of comparative toner particles 5) The following materials were added to an attritor (manufactured by Nippon Coke Co., Ltd.). • Methacrylonitrile 28.9 parts • Styrene 6.7 parts • Ethyl methacrylate 12.5 parts • Coloring agent: Pigment Blue 15: 36.0 parts A dispersion of raw materials was obtained by dispersing 5 mm diameter zirconia beads at 200 rpm for 2 hours.

[0155] Meanwhile, 735.0 parts of deionized water and 16.0 parts of trisodium phosphate dodecahydrate were added to a container equipped with a high-speed stirring device homomixer (manufactured by Primix) and a thermometer, and the temperature was raised to 60°C while stirring at 12,000 rpm. Subsequently, a calcium chloride aqueous solution, prepared by dissolving 9.0 parts of calcium chloride dihydrate in 65.0 parts of deionized water, was added to the above container, and the mixture was stirred at 12,000 rpm for 30 minutes while maintaining a temperature of 60°C, thereby obtaining an aqueous medium in which a dispersion stabilizer containing hydroxyapatite was dispersed in water.

[0156] Next, the above raw material dispersion was transferred to a container equipped with a stirring device and a thermometer, and heated to 60°C while stirring at 100 rpm. The following materials were then added. Behenyl acrylate 48.1 parts • Amorphous vinyl resin for comparison: 1 3.8 parts • DP18 (Dipentaerythritol stearate wax, melting point 79°C, manufactured by Nisshin Oillio Group Ltd.) 9.0 parts After stirring at 100 rpm for 30 minutes while maintaining a temperature of 60°C, 4.5 parts of t-butyl peroxypivalate (manufactured by NOF Corporation: Perbutyl PV) were added as a polymerization initiator and stirred for another minute. This mixture was then added to an aqueous medium being stirred at 12000 rpm using the high-speed stirring device described above. Stirring was continued at 12000 rpm for 20 minutes while maintaining a temperature of 60°C using the high-speed stirring device described above to obtain a granulated liquid.

[0157] The granulated liquid described above was transferred to a reaction vessel equipped with a reflux condenser, stirrer, thermometer, and nitrogen inlet tube, and heated to 70°C while stirring at 150 rpm under a nitrogen atmosphere. The polymerization reaction was carried out at 150 rpm for 12 hours while maintaining the temperature at 70°C to obtain a toner particle dispersion. The obtained toner particle dispersion was cooled to 48°C at a cooling rate of 0.083°C / s while stirring at 150 rpm, and then annealed for 8 hours while maintaining the temperature at 48°C. After annealing, the mixture was cooled to 30°C, and while maintaining stirring, dilute hydrochloric acid was added until the pH reached 1.5 to dissolve the above-mentioned dispersion stabilizer. Subsequently, the solid components were filtered off, thoroughly washed with deionized water, and then vacuum-dried at 30°C for 24 hours to obtain comparative toner particles 5 containing comparative amorphous vinyl resin 1.

[0158] Furthermore, resin A1' was obtained in the same manner as the manufacturing method of comparative toner particles 5 described above, except that the pigment blue ratio was 15:3 and no wax was used. When resin A1' was analyzed by NMR and the mol% was converted to mass%, it was found that resin A1' contained 48.1 mass% of monomer units polymerized from behenyl acrylate, 28.9 mass% of monomer units polymerized from methacrylonitrile, 6.7 mass% of monomer units polymerized from styrene, and 12.5 mass% of monomer units polymerized from ethyl methacrylate.

[0159] To 100.0 parts of comparative toner particles 5, 2.0 parts of silica microparticles (dimethyl silicone treated, number-average particle size of primary particles: 10 nm) were added as an external additive, and the mixture was mixed for 15 minutes at 3000 rpm using an FM mixer (manufactured by Nippon Coke Industries Co., Ltd.) to obtain comparative toner 5.

[0160] <Comparative Example 6> [Toner manufacturing using the grinding method] (Preparation of comparative crystalline vinyl resin 1) • Solvent: Toluene 100.0 parts • Monomer composition 100.0 parts (The monomer composition used was a mixture of the following polymerizable monomers in the proportions shown below.) (Behenyl acrylate (first polymerizable monomer) 92.0 parts) (Acrylonitrile (second polymerizable monomer) 7.0 parts) (Styrene (third polymerizable monomer) 1.0 part) • Polymerization initiator: t-butyl peroxypivalate (manufactured by NOF Corporation: Perbutyl PV) 1.0 part The above materials were placed in a reaction vessel equipped with a reflux condenser, stirrer, thermometer, and nitrogen inlet tube under a nitrogen atmosphere. The reaction vessel was heated to 70°C while stirring at 200 rpm, and the polymerization reaction was carried out for 12 hours to obtain a solution in which the monomer composition polymer was dissolved in toluene. Subsequently, the solution was cooled to 25°C, and then added to 1000.0 parts methanol while stirring to precipitate the methanol-insoluble components. The obtained methanol-insoluble components were filtered off, washed with methanol, and then vacuum-dried at 40°C for 24 hours to obtain comparative crystalline vinyl resin 1.

[0161] Comparative crystalline vinyl resin 1 was analyzed by NMR using the method described above, and when the mol% was converted to mass%, comparative crystalline vinyl resin 1 contained 92.0 mass% of monomer units polymerized from behenyl acrylate, 7.0 mass% of monomer units polymerized from acrylonitrile, and 1.0 mass% of monomer units polymerized from styrene.

[0162] (Preparation of comparative crystalline polyester resin 1) • 1,3-Propanediol: 34.5 parts • Malonic acid: 65.5 parts • Tin 2-ethylhexanoate: 0.5 parts The above materials were weighed into a reaction vessel equipped with a condenser, stirrer, nitrogen inlet tube, and thermocouple. After replacing the flask with nitrogen gas, the temperature was gradually increased while stirring, and the reaction was carried out for 3 hours at a temperature of 140°C while stirring. Next, the pressure in the reaction vessel was reduced to 8.3 kPa, and the reaction was carried out for 4 hours while maintaining the temperature at 200°C. Subsequently, the reaction vessel was subjected to a reduced pressure of 5 kPa or less and reacted at 200°C for 3 hours to obtain comparative crystalline polyester resin 1.

[0163] (Preparation of comparative amorphous polyester resin 1) • Bisphenol A propylene oxide adduct (average number of moles added: 2.0): 36.0 parts • Ethylene glycol: 14.0 parts Terephthalic acid: 50.0 parts Titanium tetrabutoxide (esterification catalyst): 0.5 parts The above materials were weighed into a reaction vessel equipped with a condenser, stirrer, nitrogen inlet tube, and thermocouple. Next, the flask was purged with nitrogen gas, and the temperature was gradually increased while stirring. The mixture was then reacted at 200°C while stirring for 2 hours. Furthermore, the pressure in the reaction vessel was reduced to 8.3 kPa, and the reaction was carried out for 5 hours while maintaining the temperature at 200°C. After confirming that the softening point, measured according to ASTM D36-86, reached 100°C, the temperature was lowered to stop the reaction and comparative amorphous polyester resin 1 was obtained.

[0164] (Manufacturing of comparative toner particles 6) • Amorphous polyester resin for comparison: 1:100 parts • Comparative crystalline polyester resin 1: 50.0 parts • Comparative crystalline vinyl resin 1: 70.0 parts Fischer-Tropsch wax (peak temperature of maximum endothermic peak: 90°C): 5.0 parts • Carbon Black: 10 parts The above materials were mixed using a Henschel mixer (FM-75 model, manufactured by Mitsui Mining Co., Ltd.) at a rotation speed of 1500 rpm and a rotation time of 5 min, and then kneaded in a twin-shaft kneader (PCM-30 model, manufactured by Ikegai Co., Ltd.) set to a temperature of 130°C. The resulting kneaded product was cooled and then hammered. The material was coarsely crushed to a size of 1 mm or less using a mortar and pestle to obtain coarse material. The obtained coarse material was finely ground using a mechanical crusher (T-250, manufactured by Turbo Industries Co., Ltd.). Further classification was performed using a Faculty (F-300, manufactured by Hosokawa Micron Corporation) to obtain comparative toner particles 6. The operating conditions were a classification rotor speed of 11,000 rpm and a dispersion rotor speed of 7,200 rpm.

[0165] (Manufacturing of comparison toner 6) • Comparison toner particles 6: 100 copies • Hydrophobic silica microparticles (BET: 200m2 / g): 1.0 part • Titanium oxide nanoparticles surface-treated with isobutyltrimethoxysilane (BET: 80m) 2 / g):1.0 copies The above materials were mixed in a Henschel mixer (FM-75 model, manufactured by Mitsui Miike Chemical Machinery Co., Ltd.) at a rotation speed of 1900 rpm and a rotation time of 10 min to obtain comparative toner 6.

[0166] <Comparative Example 7> [Toner manufacturing by dissolution suspension method] (Preparation of comparative amorphous polyester resin 2) • Bisphenol A ethylene oxide 2 molar adduct: 119 parts • Bisphenol A propylene oxide 3 molar adduct: 300 copies Terephthalic acid: 90 parts • Adipic acid: 200 copies • Dibutyltin oxide: 1 part The above materials were placed in a reaction vessel equipped with a condenser, a stirrer, and a nitrogen inlet tube, and reacted at 230°C under atmospheric pressure for 8 hours, followed by a further reaction under reduced pressure of 10-15 mmHg for 5 hours. Then, 22 parts of trimellitic anhydride were added to the reaction vessel and reacted at 180°C and atmospheric pressure for 2 hours. The resulting resin was pulverized using a jet pulverizer (IDS: manufactured by Nippon Pneumatic Mfg. Co., Ltd.) until the volume-average particle size was 30 μm. 300 parts of ethanol were added to 100 parts by mass of the pulverized resin and mixed for 2 hours to obtain comparative amorphous polyester resin 2.

[0167] (Preparation of comparative amorphous polyester resin 3) • Bisphenol A ethylene oxide 2 molar adduct: 264 parts • Bisphenol A propylene oxide 2 molar adduct: 520 parts Terephthalic acid: 123 parts • Adipic acid: 173 parts • Dibutyltin oxide: 1 part The above materials were placed in a reaction vessel equipped with a condenser, a stirrer, and a nitrogen inlet tube, and reacted at 230°C under atmospheric pressure for 8 hours, followed by a further reaction under reduced pressure of 10-15 mmHg for 8 hours. Then, 26 parts of trimellitic anhydride were added to the reaction vessel and reacted at 180°C and atmospheric pressure for 2 hours. The resulting resin was pulverized in the same manner as comparative amorphous polyester resin 2 and treated with ethanol to obtain comparative amorphous polyester resin 3.

[0168] (Comparative Crystalline Polyester Resin 2) ·1,6 - hexanediol: 500 parts ·Succinic acid: 550 parts ·Dibutyltin oxide: 2.5 parts Put the above materials into a reaction vessel equipped with a cooling pipe, a stirrer and a nitrogen inlet pipe, react at 200 °C for 8 hours under normal pressure, and then react for 2 hours under a reduced pressure of 10 - 15 mmHg to obtain Comparative Crystalline Polyester Resin 2. The obtained Comparative Crystalline Polyester Resin 2 was pulverized in the same manner as Comparative Amorphous Polyester Resin 2 and ethanol-treated to obtain Comparative Crystalline Polyester Resin 2.

[0169] <Synthesis of Prepolymer> Put 366 parts of 1,2 - propylene glycol, 566 parts of terephthalic acid, 44 parts of trimellitic anhydride and 6 parts of titanium tetrabutoxide into a reaction vessel equipped with a cooling pipe, a stirrer and a nitrogen inlet pipe, react at 230 °C for 8 hours under normal pressure, and then react for 5 hours under a reduced pressure of 10 - 15 mmHg to obtain Intermediate Polyester 1. Next, put 420 parts of Intermediate Polyester 1, 80 parts of isophorone diisocyanate and 500 parts of ethyl acetate into a reaction vessel equipped with a cooling pipe, a stirrer and a nitrogen inlet pipe, and react at 100 °C for 5 hours to obtain a prepolymer. <(0000898)><(0000899)>(Crystalline Resin Dispersion 1) Put the following materials into a 5 L metal container, heat and dissolve them at 75 °C, and then rapidly cool them in an ice - water bath at a rate of 27 °C / min.<000090​​​​​​​​​​​​40 parts of carbon black (Cabot Regal 400R), 60 parts of comparative amorphous polyester resin 3 as a binder, and 30 parts of water were mixed in a Henschel mixer to obtain a mixture in which water permeated the pigment aggregates. This mixture was kneaded for 45 minutes using two rolls set to a roll surface temperature of 130°C, and then pulverized to a size of 1 mmφ in a pulverizer to obtain masterbatch 1.

[0172] (Manufacturing of comparative toner particles 7) <Preparation of the oil phase> Amorphous polyester resin 2: 100 parts ·Crystalline resin dispersion 1: 34.5 parts • Paraffin wax (HNP51 (Nippon Seiro Co., Ltd.)): 10 parts • Ethyl acetate: 96 parts The above materials were placed in a container equipped with a stirring rod and thermometer, and the temperature was raised to 80°C while stirring. The temperature was maintained at 80°C for 5 hours, and then cooled to 30°C over 1 hour. Next, 11 parts of masterbatch 1 were added and mixed for 1 hour. The mixture was then transferred to another container and dispersed using a bead mill (UltraViscomill, manufactured by AIMEX) under the following conditions: liquid transfer rate of 1 kg / hr, disk peripheral speed of 6 m / sec, 0.5 mm zirconia beads packed at 80 volume%, and 3 passes. Next, 30 parts of prepolymer were added and stirred with a three-one motor for 2 hours to obtain oil phase 1.

[0173] <Preparation of the aqueous phase> 472 parts of deionized water, 81 parts of a 50% aqueous solution of sodium dodecyldiphenyl ether disulfonate (Eleminol MON-7: manufactured by Sanyo Chemical Industries, Ltd.), 67 parts of a 1% aqueous solution of carboxymethylcellulose as a thickener, and 54 parts of ethyl acetate were mixed and stirred to obtain aqueous phase 1, which is a milky white liquid.

[0174] <Emulsification process> The entire amount of oil phase 1 was mixed at 5,000 rpm for 1 minute using a TK homomixer (manufactured by Tokushu Kika Co., Ltd.), then 321 parts of water phase 1 were added, and the mixture was mixed for 20 minutes using the TK homomixer while adjusting the rotation speed between 8,000 and 13,000 rpm to obtain slurry 1.

[0175] <Solvent removal> Slurry 1 was placed in a container equipped with a stirrer and thermometer, and the solvent was removed at 30°C for 8 hours to obtain dispersed slurry 1.

[0176] <Washing → Drying> (1): 100 parts of dispersion slurry 1 were filtered under reduced pressure, then 100 parts of deionized water were added to the filter cake, mixed with a TK homomixer (rotation speed 12,000 rpm for 10 minutes), and then filtered. (2): 100 parts of deionized water were added to the filtration cake from (1), and the mixture was mixed in a TK homomixer with ultrasonic vibration (at a rotation speed of 12,000 rpm for 30 minutes), followed by vacuum filtration. This procedure was repeated until the electrical conductivity of the slurry was 10 μS / cm or less. (3): Add 10% hydrochloric acid to the slurry solution from (2) so that the pH becomes 4, stir with a three-one motor, and filter after 30 minutes. (4): 100 parts of deionized water were added to the filtration cake from (3), mixed with a TK homomixer (at 12,000 rpm for 10 minutes), and then filtered. This operation was repeated until the electrical conductivity of the slurry was 10 μS / cm or less to obtain filtration cake 1. The remaining dispersion slurry 1 was washed in the same manner and added to the mixture as filtration cake 1. (5) The filtered cake 1 was dried in a circulating air dryer at 45°C for 48 hours, and then sieved with a 75 μm mesh to obtain comparative toner particles 7.

[0177] (Manufacturing of comparison toner 7) Comparative toner 7 was obtained by adding 1 part of hydrophobic silica with a primary particle size of 30 nm and 0.5 parts of hydrophobic silica with a primary particle size of 10 nm to 50 parts of comparative toner 7 and mixing them in a Henschel mixer.

[0178] The physical properties of the obtained comparative toners 5-7 are shown in Table 4, and the evaluation results are shown in Table 5. [Table 3] In the table, the paraffin wax used for toner 29 and comparative toner 7 is HNP51 (Nippon Seiro Co., Ltd.). [Table 4]

[0179] In Table 4, (A) shows the number of endothermic peaks observed during heating process 1. (B) shows the number of endothermic peaks observed during heating process 2. The endothermic peaks observed during each heating process in Examples 1-30 and Comparative Examples 1-5 are all "endothermic peaks originating from crystalline vinyl resin" measured by the method described above. In Comparative Example 6, two endothermic peaks were observed in both heating processes 1 and 2. These peaks are thought to be endothermic peaks originating from the crystalline vinyl resin and the crystalline polyester resin, respectively. In Comparative Example 7, one endothermic peak was observed during heating process 1. This peak is thought to be an endothermic peak originating from the crystalline polyester resin.

[0180] <Toner Evaluation Method> The toners for Examples 1-30 and Comparative Examples 1-7 were evaluated as follows. The evaluation results are shown in Table 5.

[0181] <1> Evaluation of low-temperature fixation properties A toner-filled process cartridge (a process cartridge for a laser beam printer (LBP-712Ci, manufactured by Canon Inc.)) was left at 25°C and 40% RH humidity for 48 hours. Using a modified Canon LBP-712Ci laser beam printer, modified to operate even without the fuser unit, an unfixed image of a 10mm x 10mm square image pattern, evenly distributed at 9 points across the entire transfer paper, was output. The toner amount on the transfer paper was 0.80 mg / cm². 2 The fixing start temperature was then evaluated. The transfer paper used was A4 paper (Proverbond paper: 105 g / m²). 2 (Fox River Industries) was used. The fixing device used was an external fixing device obtained by removing the fixing device of a laser beam printer (LBP-712Ci, manufactured by Canon Inc.) from the printer and modifying it to operate outside the laser beam printer. The external fixing device was used to increase the fixing temperature in 5°C increments from 90°C and perform fixing under the condition of a process speed of 360 mm / s. The fixing images were visually inspected, and the low-temperature fixing property was evaluated with the lowest temperature at which no cold offset occurred as the fixing start temperature.

[0182] <2>Evaluation of folding resistance Using a commercially available Canon printer LBP-712Ci, the folding resistance was evaluated. The process cartridge filled with toner was left in an environment of 25°C and 40% RH for 48 hours. Using the above printer, two solid images of 50 mm × 50 mm with a toner loading of 0.8 mg / cm 2 were printed at the fixing start temperature + 10°C measured in the above evaluation of low-temperature fixing property at the center of the transfer paper.

[0183] Of the printed solid images, one was subjected to the following folding operation. For the folding operation, the transfer paper was folded so that the valley fold line traced the diagonal of the solid image, and the transfer paper was folded so that the mountain fold line bisected each side of the transfer image and traced a cross at the center of the solid image. That is, after one folding operation, two valley fold lines and two mountain fold lines were formed on the solid image. The folding operation was performed five times. That is, after performing the above folding, the transfer paper was unfolded and folded again at the same location, repeating a total of five folds. After the folding operation was completed, the transfer paper was unfolded, covered with a soft thin paper (product name "Dasper", manufactured by Otsu Sangyo Co., Ltd.), and rubbed back and forth eight times while applying a load of 4.9 kPa from above the thin paper. The image density was measured with the intersection of the four folding lines as the center of the solid image. Of the printed solid images, the other one was not subjected to the folding operation and only the above rubbing operation was performed, and the image density was measured at the center of the solid image.

[0184] Image density was measured using a color reflection densitometer (X-Rite 404A, manufactured by X-Rite). The image density at the center of solid images on transfer paper that had been folded and transfer paper that had not been folded was compared, and the rate of image density reduction was evaluated. The image density reduction rate was calculated using the following formula. A smaller image density reduction rate indicates better bending resistance. Image density reduction rate (%) = {(Image density of unfolded transfer paper) - (Image density of folded transfer paper)} / (Image density of unfolded transfer paper) × 100

[0185] <3> Evaluation of image loading capacity Using the aforementioned modified LBP-712Ci, the image paper (Canon Office Planner 64g / m²) was used. 2 ) Above is an unfixed toner image measuring 2.0 cm vertically and 15.0 cm horizontally (0.6 mg / cm²). 2 A ) was formed at a point 1.0 cm from the top edge in the paper feeding direction. Next, the obtained unfixed image was fixed at a temperature 20°C higher than the fixing start temperature measured in the evaluation of low-temperature fixing performance above to obtain a fixed image paper. The following evaluations were performed on the resulting fixed image paper. Unused paper (Canon Office Planner 64g / m²) 2 500 sheets of paper were stacked, and a sheet of fixing image paper was placed on top of the 500th sheet, with the image portion facing downwards and touching the paper. Furthermore, 700 sheets of unused paper of the same type were stacked on top of the fixing image paper, sandwiching it between them. This was then placed in a temperature-controlled chamber at 45°C and 70% RH for 72 hours before being removed from the chamber. Subsequently, the fixed image of the unused paper (the 500th sheet of paper mentioned above) that had been in contact with the fixed image paper, The reflectance of the portion of the paper that was in contact with the image was measured. The reflectance of the portion of the unused paper that was not in contact with the image was subtracted from the measured reflectance to determine the reflectance of the image that had been color-transferred from the fixed image.

[0186] The image stacking capability was evaluated based on the measured reflectance. The reflectance was measured using a TC-6DS (manufactured by Tokyo Denshoku). A smaller reflectance value indicates better image stacking capability.

[0187] <4> Evaluation of abrasion resistance The fixed image was printed using the same method as described above for evaluating low-temperature fixability. The fixation temperature was set to 5°C higher than the fixation start temperature measured in the evaluation of low-temperature fixability above. A soft, thin sheet of paper (Dasper, manufactured by Ozu Sangyo Co., Ltd.) was placed over the image area of ​​the obtained fixed image, and the image area was rubbed back and forth five times while applying a load of 4.9 kPa from above the thin sheet of paper. The image density was measured before and after rubbing, and the rate of decrease in image density ΔD (%) was calculated using the following formula. This ΔD (%) was used as an indicator of abrasion resistance. ΔD(%) = {(Image density before rubbing - Image density after rubbing) / Image density before rubbing} × 100 Image density was measured using a color reflection densitometer (X-Rite 404A, manufactured by X-Rite). A smaller value of ΔD(%) indicates better abrasion resistance.

[0188] <5> Evaluation of heat resistance and preservation properties To evaluate the stability during storage, we conducted an evaluation of its heat resistance. 5g of toner was placed in a 100ml plastic cup and left for 3 days at a temperature of 50°C and a humidity of 70%RH. The degree of toner aggregation was then measured and evaluated as follows. As the measuring device, a "Powder Tester" (manufactured by Hosokawa Micron Corporation) was used, with a digital display vibration meter "DigiVibro MODEL 1332A" (manufactured by Showa Sokki Co., Ltd.) connected to the side of the vibration table. Then, on the vibration table of the Powder Tester, sieves with a mesh size of 38 μm (400 mesh), 75 μm (200 mesh), and 150 μm (100 mesh) were stacked in that order from bottom to top. The measurements were performed in an environment of 23°C and 60% RH as follows. (1) The vibration amplitude of the vibration table was pre-adjusted so that the displacement value of the digital display vibration meter was 0.60 mm (peak-to-peak). (2) The toner that had been left for 3 days as described above was then left for 24 hours in an environment of 23°C and 60% RH. Then, 5.00 g of toner was weighed and gently placed on the top sieve with a mesh size of 150 μm. (3) After vibrating the sieves for 15 seconds, the mass of toner remaining on each sieve was measured, and the degree of cohesion was calculated based on the following formula. The evaluation results are shown in Table 5. Cohesion (%) = {(Sample mass on a sieve with a mesh size of 150 μm (g)) / 5.00 (g)} × 100 + {(Sample mass on a sieve with a mesh size of 75 μm (g)) / 5.00 (g)} × 100 × 0.6 + {(Sample mass on a sieve with a mesh size of 38 μm (g)) / 5.00 (g)} × 100 × 0.2 A lower cohesiveness (%) value indicates superior heat resistance and storage properties.

[0189] [Table 5]

[0190] This disclosure relates to the following configuration. (Composition 1) A toner having toner particles containing a resin component, The resin component contains crystalline vinyl resin, When the temperature at which the differential curve of the DSC endothermic curve shows a minimum value during heating in the differential scanning calorimetry of the toner is defined as the peak top temperature, In heating process 1, where the temperature is raised from 20°C to 180°C at a heating rate of 10°C / min, there is one endothermic peak originating from the crystalline vinyl resin. In heating process 2, which follows heating process 1 by cooling from 180°C to 20°C at a rate of 10°C / min, and then heating again from 20°C to 180°C at a rate of 10°C / min, two endothermic peaks originating from the crystalline vinyl resin are present. In the heating process 1, the endothermic peak originating from the crystalline vinyl resin is defined as endothermic peak P1. In the heating process 2, of the two endothermic peaks originating from the crystalline vinyl resin, the endothermic peak with the lower temperature peak top temperature is defined as endothermic peak P21, and the endothermic peak with the higher temperature peak top temperature is defined as endothermic peak P22. When the amount of heat absorbed at the endothermic peak P1 is S1 (J / g), the amount of heat absorbed at the endothermic peak P21 is S21 (J / g), and the amount of heat absorbed at the endothermic peak P22 is S22 (J / g), S1, S21, and S22 satisfy the following formulas (1) to (3): Formula (1) S1≧(S21+S22)≧S1×0.25 Formula (2) S21≧S1×0.10 Formula (3) S22≧S1×0.10 A toner characterized by the following features. (Configuration 2) The toner according to configuration 1, wherein when the peak top temperature of the endothermic peak P1 is denoted as T1 (°C), T1 is 50.0°C or higher and 80.0°C or lower. (Composition 3) The toner according to configuration 1 or 2, wherein when the peak top temperature of the endothermic peak P21 is defined as T21 (°C), T21 is 45.0°C or higher. (Composition 4) The toner according to any one of configurations 1 to 3, wherein when the peak top temperature of the endothermic peak P21 is T21 (°C) and the peak top temperature of the endothermic peak P22 is T22 (°C), T21 and T22 satisfy the following formula (4). Formula (4) 20.0≧(T22-T21)≧3.0 (Composition 5) The toner according to any one of configurations 1 to 4, wherein the crystalline vinyl resin has monomer units (a) represented by the following formula (5). TIFF2026049870000009.tif52153 (in formula (5), R 1 L represents a hydrogen atom or a methyl group. 1 (where m represents a single bond, ester bond, or amide bond, and m is an integer between 15 and 30.) (Composition 6) The toner according to any one of configurations 1 to 5, wherein the mass ratio of the crystalline vinyl resin in the resin component is 30.0% by mass or more. (Composition 7) The crystalline vinyl resin is A crystalline vinyl resin A having a monomer unit (a) content of 50.0% by mass or more and 70.0% by mass or less, A crystalline vinyl resin B having a monomer unit (a) content of 80.0% by mass or more and 100.0% by mass or less, The toner according to configuration 5 or 6, which contains the toner described in configuration 5 or 6. (Composition 8) The toner according to any one of configurations 1 to 7, wherein the toner particles contain a bifunctional or more functional ester wax.

Claims

1. A toner having toner particles containing a resin component, The resin component contains crystalline vinyl resin, When the temperature at which the differential curve of the DSC endothermic curve shows a minimum value during heating in the differential scanning calorimetry of the toner is defined as the peak top temperature, In heating process 1, where the temperature is raised from 20°C to 180°C at a heating rate of 10°C / min, there is one endothermic peak originating from the crystalline vinyl resin. In heating process 2, which follows heating process 1 by cooling from 180°C to 20°C at a rate of 10°C / min, and then heating again from 20°C to 180°C at a rate of 10°C / min, two endothermic peaks originating from the crystalline vinyl resin are present. In the heating process 1, the endothermic peak originating from the crystalline vinyl resin is defined as endothermic peak P1. In the heating process 2, of the two endothermic peaks originating from the crystalline vinyl resin, the endothermic peak with the lower temperature peak top temperature is defined as endothermic peak P21, and the endothermic peak with the higher temperature peak top temperature is defined as endothermic peak P22. When the amount of heat absorbed at the endothermic peak P1 is S1 (J / g), the amount of heat absorbed at the endothermic peak P21 is S21 (J / g), and the amount of heat absorbed at the endothermic peak P22 is S22 (J / g), S1, S21 and S22 satisfy the following formulas (1) to (3): Formula (1) S1≧(S21+S22)≧S1×0.25 Formula (2) S21≧S1×0.10 Formula (3) S22≧S1×0.10 A toner characterized by the following features.

2. The toner according to claim 1, wherein when the peak top temperature of the endothermic peak P1 is denoted as T1 (°C), T1 is 50.0°C or higher and 80.0°C or lower.

3. The toner according to claim 1, wherein when the peak top temperature of the endothermic peak P21 is T21 (°C), T21 is 45.0°C or higher.

4. The toner according to claim 1, wherein when the peak top temperature of the endothermic peak P21 is T21 (°C) and the peak top temperature of the endothermic peak P22 is T22 (°C), T21 and T22 satisfy the following formula (4). Formula (4) 20.0≧(T22-T21)≧3.0

5. The toner according to any one of claims 1 to 4, wherein the crystalline vinyl resin has monomer units (a) represented by the following formula (5). (In formula (5), R １ L represents a hydrogen atom or a methyl group. １ (where m represents a single bond, ester bond, or amide bond, and m is an integer between 15 and 30.)

6. The toner according to any one of claims 1 to 4, wherein the mass ratio of the crystalline vinyl resin in the resin component is 30.0% by mass or more.

7. The crystalline vinyl resin is A crystalline vinyl resin A having a monomer unit (a) content of 50.0% by mass or more and 70.0% by mass or less, A crystalline vinyl resin B having a monomer unit (a) content of 80.0% by mass or more and 100.0% by mass or less, The toner according to claim 5, comprising the same toner.

8. The toner according to any one of claims 1 to 4, wherein the toner particles contain a bifunctional or more functional ester wax.

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