Toner, external additives for toner, and fine particles

Abstract

To provide a toner that is excellent in low temperature fixability and can maintain initial cleaning properties even after the toner continuously receives mechanical stress, an external additive for toner, and fine particles.SOLUTION: A toner has a toner particle containing a binder resin and a colorant and fine particles present on the surface of the toner particle. The fine particle is solid and has a substantially hemispherical shape and has a substantially flat surface and a curved surface. The number average value of the longest diameter w of the substantially flat surface is 10 nm or more and 400 nm or less. An external additive for toner is solid and has a substantially hemispherical shape and has a substantially flat surface and a curved surface. The number average value of the longest diameter w of the substantially flat surface is 10 nm or more and 400 nm or less. Fine particles are solid and have a substantially hemispherical shape and have a substantially flat surface and a curved surface. The number average value of the longest diameter w of the substantially flat surface is 10 nm or more and 400 nm or less.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a toner, an external additive for a toner, and fine particles for developing electrostatic images used in image forming methods such as electrophotography and electrostatic printing. [Background technology]

[0002] Laser printers and copiers are typical devices that use toner in electrophotography. In recent years, there has been an increasing demand for these devices to be more compact, consume less power, and produce higher image quality, and various studies are being conducted to develop superior toners that can meet these demands.

[0003] Among these, a widely known technique is to externally add various fine particles to the surface of toner particles in a toner. Patent Document 1 proposes a toner with superior transferability and cleanability by externally adding fine particles with a specific size, aspect ratio, and shape to highly circular toner particles. However, issues remain, such as the migration of the external additives from the surface of the toner particles to other components with continuous use, and the rolling or embedding of the external additives on the surface of the toner particles. In particular, in recent designs that minimize the amount of toner filled in a cartridge so that the toner is used up when the cartridge is replaced, the toner is repeatedly subjected to mechanical stress, and the above-mentioned issues become apparent.

[0004] Therefore, Patent Document 2 proposes a method of suppressing the detachment of external additives from the surface of toner particles and the rolling of external additives on the surface of toner particles by using large-diameter hemispherical microparticles as external additives in toner. However, the technology described in Patent Document 2 generates hollow hemispherical organic microparticles by rupturing hollow organic microparticles and releasing the internal gas, which poses a problem of functional degradation due to cracking of the microparticles themselves under conditions of strong external force. In addition, because the shape of the hemispheres retains air, there is an issue with the low-temperature fixability of the toner due to the heat insulating effect.

[0005] Furthermore, Patent Document 3 discloses a method for forming a coating layer of a silicon compound on the surface of toner particles to obtain a toner that has excellent development and transfer properties even after long-term use. However, compared to a method in which an external additive is added to fine particles, the inhibition of fixability due to the high degree of coating on the surface of the toner particles is not negligible. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2017-138482 [Patent Document 2] Patent No. 5223382 [Patent Document 3] Patent No. 3943781 Summary of the Invention [Problem to be solved by the invention]

[0007] An object of the present invention is to provide a toner, an external additive for a toner, and fine particles that have excellent low-temperature fixing properties and can maintain initial cleaning properties even after the toner has been subjected to continuous mechanical stress. [Means for solving the problem]

[0008] The present invention relates to a toner particle containing a binder resin and a colorant, fine particles present on the surface of the toner particles; A toner having the fine particles are solid and substantially hemispherical, and have substantially flat and curved surfaces; The toner has a number average value of the longest diameter w of the approximately flat surface of 10 nm or more and 400 nm or less.

[0009] The present invention also provides an external toner additive that is solid and substantially hemispherical and has substantially flat and curved surfaces, The external toner additive has a number average value of the longest diameter w of the approximately flat surface of 10 nm or more and 400 nm or less.

[0010] The present invention also provides a microparticle that is solid and approximately hemispherical and has approximately flat and curved surfaces, The particle has a number average value of the longest diameter w of the approximately flat surface of 10 nm or more and 400 nm or less. [Effects of the Invention]

[0011] According to the present invention, it is possible to provide a toner, an external toner additive, and fine particles that have excellent low-temperature fixing properties and can maintain their initial cleaning properties even after the toner has been subjected to continuous mechanical stress. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 10 is a diagram showing an example of a substantially hemispherical shape. [Figure 2A] 1 is a diagram showing an example of the maximum length df, maximum height h, and maximum width b when observing a cross section of a substantially hemispherical fine particle or external toner additive. FIG. [Figure 2B] 1 is a diagram showing an example of the maximum length df, maximum height h, and maximum width b when observing a cross section of a substantially hemispherical fine particle or external toner additive. FIG. [Figure 2C] 1 is a diagram showing an example of the maximum length df, maximum height h, and maximum width b when observing a cross section of a substantially hemispherical fine particle or external toner additive. FIG. [Figure 2D] 1 is a diagram showing an example of the maximum length df, maximum height h, and maximum width b when observing a cross section of a substantially hemispherical fine particle or external toner additive. FIG. [Figure 2E] 10A and 10B are diagrams showing examples of ellipses e1 and e2 when observing the cross section of a substantially hemispherical fine particle or external toner additive. [Figure 2F] 10A and 10B are diagrams showing examples of ellipses e1 and e2 when observing the cross section of a substantially hemispherical fine particle or external toner additive. [Figure 2G] FIG. 1 is a diagram showing an example of the major axis l1 of an ellipse e1, the major axis l2 of an ellipse e2, the minor axis s1 of the ellipse e1, and the minor axis s2 of the ellipse e2 when observing a cross section of a substantially hemispherical fine particle or external toner additive. [Figure 2H]FIG. 1 is a diagram showing an example of the major axis l1 of an ellipse e1, the major axis l2 of an ellipse e2, the minor axis s1 of the ellipse e1, and the minor axis s2 of the ellipse e2 when observing a cross section of a substantially hemispherical fine particle or external toner additive. [Figure 3] 1 is a diagram showing an example of the longest diameter w of a substantially hemispherical fine particle or external toner additive when observed from an arbitrary direction. [Figure 4] 10A and 10B are diagrams showing examples of angles of substantially hemispherical fine particles when the surface of a toner particle is observed from an arbitrary direction. DETAILED DESCRIPTION OF THE INVENTION

[0013] In the present invention, unless otherwise specified, the expression "XX to XX" representing a numerical range means a numerical range including the lower and upper limits, which are the endpoints. The present invention will be described in detail below.

[0014] The present invention relates to a toner particle containing a binder resin and a colorant, fine particles present on the surface of the toner particles; A toner having the fine particles are solid and substantially hemispherical, and have substantially flat and curved surfaces; The number average value of the longest diameter w of the approximately flat surface is 10 nm or more and 400 nm or less.

[0015] The present invention also provides an external toner additive that is solid and substantially hemispherical and has substantially flat and curved surfaces, The number average value of the longest diameter w of the approximately flat surface is 10 nm or more and 400 nm or less.

[0016] The present invention also provides a microparticle that is solid and approximately hemispherical and has approximately flat and curved surfaces, The number average value of the longest diameter w of the approximately flat surface is 10 nm or more and 400 nm or less.

[0017] The toner of the present invention has fine particles on the surface of toner particles containing a binder resin and a colorant, and it is essential that the fine particles are solid and approximately hemispherical. Furthermore, it is essential that the external toner additive of the present invention is solid and approximately hemispherical. Furthermore, it is essential that the fine particles of the present invention are solid and approximately hemispherical.

[0018] In this specification, "solid" means that the interior of the particle is filled with a solid and is not hollow. The state in which the interior of the particle is filled with a solid and is not hollow can be confirmed by observing the cross section of the particle.

[0019] If the particles are solid, they can remain on the surface of the toner particles without losing their approximately hemispherical shape, even when subjected to continuous mechanical stress. A typical example of a situation in which the particles on the surface of the toner particles are subjected to continuous mechanical stress is when the amount of toner filled in the cartridge is reduced to a minimum, so that the toner is used up by the time the cartridge is replaced. Hereinafter, this type of design will be referred to as a "toner use-up design." In a toner use-up design, when the amount of toner in the toner cartridge is low, i.e., when the cartridge is about to be replaced, the same toner particles are used for development and then returned without being developed, which is a cycle that is repeated more frequently. Therefore, the toner is subjected to repeated mechanical stress. Even under such conditions, if the particles are solid, they can remain on the surface of the toner particles without losing their approximately hemispherical shape, thereby maintaining the initial cleaning performance, which is one of the advantages of the present invention.

[0020] Furthermore, if the particles are solid, there is no air inside the particles, and the insulating effect of air does not inhibit heat conduction during fixing. It is generally known that the thermal conductivity of air is 0.023 [W / (m·K)], while the thermal conductivity of silicone resin is 0.13-0.14 [W / (m·K)], and that of silica is 1.38 [W / (m·K)]. Therefore, when particles are present on the surface of toner particles, solid particles with a solid interior conduct heat faster than hollow particles. As a result, this is effective in achieving low-temperature fixability.

[0021] In the present invention, it is also necessary that the fine particles present on the surface of the toner particles are approximately hemispherical and have approximately flat and curved surfaces. Furthermore, in another embodiment of the present invention, the external toner additive is required to be approximately hemispherical and have approximately flat and curved surfaces. Furthermore, in another aspect of the present invention, it is necessary that the fine particles are approximately hemispherical and have approximately flat and curved surfaces.

[0022] When the fine particles or external toner additives are substantially hemispherical and have substantially flat and curved surfaces, the fine particles or external toner additives adhere to the surfaces of the toner particles so that the substantially flat surfaces of the fine particles or external toner additives are in contact with the surfaces of the toner particles. This prevents the fine particles or external toner additives from migrating from the surfaces of the toner particles and from rolling on the surfaces of the toner particles. As a result, the fine particles or external toner additives present on the surfaces of the toner particles can maintain their initial cleaning properties even when they are repeatedly subjected to mechanical stress.

[0023] Furthermore, if the microparticles or external toner additives are approximately hemispherical and have approximately flat and curved surfaces, the curved surfaces of the microparticles or external toner additives adhered to the surfaces of the toner particles become the contact surfaces with the member, thereby reducing the contact area between the member and the toner particles and minimizing the adhesive force. For example, if the member is a photosensitive drum, the reduced adhesive force between the photosensitive drum and the toner particles improves the transferability of the toner. As a result, the amount of residual toner after transfer is reduced, thereby achieving the effect of improving initial cleaning performance.

[0024] In this specification, the term "approximately hemispherical" refers to a shape obtained by cutting an ellipsoid along an arbitrary plane. As shown in FIG. 1, when an ellipsoid is divided into two by an arbitrary plane, one of the two solid bodies (the solid body indicated by a dotted pattern in FIG. 1) is an example of the approximately hemispherical shape of the present invention. In this specification, the term "ellipsoid" includes a solid body that approximates a perfect sphere or an ellipsoid, and the arbitrary plane may or may not pass through the center of the ellipsoid. Note that the method for producing approximately hemispherical microparticles or external toner additives in this specification is not limited to a method for cutting an ellipsoid, but also includes a bottom-up method of forming the microparticles or external toner additives on a substrate having an approximately flat surface. In the bottom-up method of forming the microparticles or external toner additives on a substrate having an approximately flat surface, using particles as the substrate that have an approximately flat surface and a particle size several tens of times larger than the size of the microparticles or external toner additives facilitates the production of approximately hemispherical microparticles or external toner additives having approximately flat and curved surfaces.

[0025] The fact that a microparticle or an external toner additive is substantially hemispherical can be confirmed by observing a cross section of the microparticle or the external toner additive that intersects with a substantially flat surface. Specifically, when observing the cross section of the microparticle or the external toner additive, it is determined to be substantially hemispherical if the following two conditions are met: (1) In the cross section of the microparticle or the external toner additive that intersects with the substantially flat surface, the line connecting two intersection points Pa and Pb of the line Lf derived from the substantially flat surface and the line Lc derived from the curved surface is defined as an imaginary line Li, the longest distance between the imaginary line Li and the line Lf derived from the substantially flat surface is defined as a maximum length df, and in the line Ls1 that intersects perpendicularly with the imaginary line Li on the cross section, the distance Da between the intersection point Pc of the imaginary line Li and the line Ls1 and the intersection point Pe of the line Lc derived from the curved surface and the line Ls1, and the intersection point Pd of the line Lf derived from the substantially flat surface and the line Ls1 and the intersection point Pe of the line Lc derived from the curved surface and the line Ls1 are defined as (2) In a cross section of the fine particle or toner external additive intersecting with a substantially flat surface, in an ellipse e1 that passes through two intersections of the substantially flat surface and the curved surface and circumscribes the curved surface of the fine particle or toner external additive, and in an ellipse e2 that passes through two intersections of the substantially flat surface and the curved surface and inscribes the curved surface of the fine particle or toner external additive, the number average value of the ratio l1 / l2 of the major axis l1 of the ellipse e1 to the major axis l2 of the ellipse e2 is 0.90 to 1.10, and the number average value of the ratio s1 / s2 of the minor axis s1 of the ellipse e1 to the minor axis s2 of the ellipse e2 is 0.90 to 1.10. Examples of the maximum length df and the maximum height h are shown in Figures 2A to 2D. The number average value of the ratio df / h is preferably 0.00 or more and 0.05 or less, because the fine particles or external toner additives adhere more firmly to the surface of the toner particles, improving the cleaning properties of the toner after it has been subjected to continuous mechanical stress. Examples of the ellipse e1, the ellipse e2, the major axis l1 of the ellipse e1, the major axis l2 of the ellipse e2, the minor axis s1 of the ellipse e1, and the minor axis s2 of the ellipse e2 are shown in Figures 2E to 2H.

[0026] In the toner of the present invention, the fine particles present on the surface of the toner particles have a substantially flat surface and a curved surface, and the number average value of the longest diameter w of the substantially flat surface is 10 nm or more and 400 nm or less. Furthermore, in another aspect of the present invention, the external toner additive has a substantially flat surface and a curved surface, and the number average value of the longest diameter w of the substantially flat surface is 10 nm or more and 400 nm or less. In yet another aspect of the present invention, the fine particles have a substantially flat surface and a curved surface, and the number average value of the longest diameter w of the substantially flat surface is 10 nm or more and 400 nm or less.

[0027] The maximum diameter w of the approximate plane of the fine particle or external toner additive is calculated by observing the fine particle or external toner additive from above (the direction from which the approximate plane of the fine particle or external toner additive can be observed) and taking the longest distance between any two points on the periphery of the approximate plane. Figure 3 shows an example of the maximum diameter w.

[0028] When the number-average longest diameter w of the microparticles or external toner additives in the approximately flat surface is 10 nm or more and 400 nm or less, the initial cleanability and low-temperature fixability of the toner are improved. When the number-average longest diameter w is 10 nm or more, the probability that the microparticles or external toner additives present on the surface of the toner particles, rather than the surface of the toner particles, will come into contact with the component increases. Therefore, when the number-average longest diameter w is 10 nm or more, the adhesion force of the toner particles to the component can be maintained low. As a result, the amount of residual toner after transfer is reduced, which is advantageous for initial cleanability. When the number-average longest diameter w is 30 nm or more, preferably 50 nm or more, the initial cleanability is further improved. Furthermore, when the number-average longest diameter w is 400 nm or less, the surface area of ​​the toner particles covered by each microparticle or external toner additive can be prevented from becoming too large, which is advantageous for low-temperature fixability of the toner. When the number-average longest diameter w is 300 nm or less, preferably 250 nm or less, the low-temperature fixability of the toner is more effective.

[0029] The shape and number-average longest diameter w of the microparticles or external toner additives can be controlled by the type and number of parts of the monomer used in producing the microparticles or external toner additives, the reaction temperature during polymerization of the monomer, the reaction time, the pH of the reaction medium and reaction system, and the type and concentration of the dispersant. Furthermore, when microparticles or external toner additives are produced by a bottom-up formation method on a substrate, the shape and number-average w of the microparticles or external toner additives can also be controlled by the shape and size of the substrate.

[0030] In the toner of the present invention, when the surface of the toner particle is observed, it is preferable that the fine particles have an approximately flat surface. When observing the surface of a toner particle, if a roughly flat surface of the fine particles is observed, some of the fine particles are in a state where they can easily migrate from the surface of the toner particle to the surface of the member. The fine particles that have migrated to the surface of the member will adhere to the surface of the member so that the roughly flat surface comes into contact with the surface of the member. For example, if the member is a cleaning blade, some of the fine particles that have migrated to the cleaning blade will adhere to the surface of the cleaning blade so that the roughly flat surface comes into contact with the surface of the cleaning blade. Therefore, the curved surface of the fine particles on the cleaning blade becomes the contact surface with the photosensitive drum. As a result, torque during cleaning is reduced, making it less likely for particles to slip through, thereby improving initial cleaning performance.

[0031] Because the microparticles or external toner additives of the present invention have an approximately hemispherical shape, many of the microparticles or external toner additives adhere to the toner particle surface so that their approximately flat surface is in contact with the surface of the toner particle, thereby inhibiting migration from the toner particle surface. However, because there is no network between the microparticles or external toner additives or no chemical bonding between the microparticles or external toner additives and the toner particle, some of the microparticles or external toner additives migrate from the toner particle surface to the surface of the component. When the surface of the toner particles is observed to be approximately flat, this does not mean that all of the microparticles or external toner additives adhere to the toner particle surface so that their approximately flat surface is in contact with the surface of the toner particle, but rather that some of the microparticles or external toner additives are capable of migrating from the toner particle surface to the surface of the component. In this state, the microparticles or external toner additives that have migrated to the surface of the component contribute to improving initial cleaning performance, and the microparticles or external toner additives that have adhered to the surface of the toner particle contribute to maintaining initial cleaning performance. As a result, good cleaning performance can be achieved even when the toner is repeatedly subjected to mechanical stress.

[0032] In the toner of the present invention, when the surface of a toner particle is observed from any one direction, the angle of the particle when the substantially flat surface of the particle is in contact with the surface of the toner particle is defined as 0°. A substantially flat surface is defined as a particle having an angle of more than 90° but less than 270°. In the toner of the present invention, a substantially flat surface is defined as a particle when 1.0% or more of the particles present on the surface of the toner particle are substantially flat. Figure 4 shows an example of the angle of the particles when the surface of the toner particle is viewed from any one direction. From the viewpoint of preventing component contamination, the proportion of particles having a substantially flat surface is preferably 40.0% or less by number. Having a proportion of particles having a substantially flat surface of 40.0% or less by number results in a good balance between the particles adhering to the surface of the toner particle and the particles adhering to the surface of the component, improving the cleanability of the toner after repeated mechanical stress. It is more preferable that the proportion of particles having a substantially flat surface be 20.0% or less by number on the surface of the toner particle.

[0033] The proportion of fine particles that are observed to have a substantially flat surface when observing the surface of toner particles can be controlled by the shape of the fine particles, the number of fine particles added to the toner, and the conditions for adding the fine particles. As mentioned above, the shape of the fine particles can be controlled by the type and number of monomers for the fine particles, the reaction temperature and reaction time during particle polymerization, the pH of the reaction medium and reaction system, the type and concentration of the dispersant, and the shape and size of the substrate during the production of the fine particles.

[0034] Furthermore, in the toner of the present invention, when a cross section of a fine particle present on the surface of a toner particle intersecting with an approximate plane is observed, the imaginary line Li is a line connecting two intersection points Pa and Pb of a line Lf derived from the approximate plane and a line Lc derived from the curved surface, and on a line Ls1 that intersects perpendicularly with the imaginary line Li, the maximum height h is the distance at which either one of the distance Da between the intersection point Pc of the imaginary line Li and the line Ls1 and the intersection point Pe of the line Lc and the line Ls1, and the distance Db between the intersection point Pd of the line Lf and the line Ls1 and the intersection point Pe is the distance at which the distance Dc between the two intersection points Pf and Pg of the line Ls2 and the line Lc is the maximum on a line Ls2 that is parallel to the imaginary line Li is the distance at which the distance Dc between the two intersection points Pf and Pg of the line Ls2 and the line Lc is the maximum, and the number average value of the ratio h / b of the maximum height h to the maximum width b is preferably 0.33 or more and 0.80 or less.

[0035] Furthermore, in another aspect of the present invention, when a cross section of the external toner additive intersecting with an approximate plane of the external toner additive is observed, the virtual line Li is a line connecting two intersection points Pa and Pb of a line Lf derived from the approximate plane and a line Lc derived from the curved surface, and on a line Ls1 that intersects perpendicularly with the virtual line Li, the maximum height h is the distance at which one of the distance Da between the intersection point Pc of the virtual line Li and the line Ls1 and the intersection point Pe of the line Lc and the line Ls1, and the distance Db between the intersection point Pd of the line Lf and the line Ls1 and the intersection point Pe is the distance at which the distance Dc between the intersection points Pf and Pg of the line Ls2 and the line Lc is the maximum on a line Ls2 that is parallel to the virtual line Li is the distance at which the distance Dc between the two intersection points Pf and Pg of the line Ls2 and the line Lc is the maximum, and the number average value of the ratio h / b of the maximum height h to the maximum width b is preferably 0.33 or more and 0.80 or less.

[0036] Furthermore, in another aspect of the present invention, when a cross section of a microparticle intersecting an approximate plane of the microparticle is observed, it is preferable that the number average value of the ratio h / b of the maximum height h to the maximum width b is 0.33 or more and 0.80 or less, where the imaginary line Li is the line connecting two intersection points Pa and Pb between a line Lf derived from the approximate plane and a line Lc derived from the curved surface, and the maximum height h is the distance at which one of the distance Da between the intersection point Pc of the imaginary line Li and the line Ls1 and the intersection point Pe of the line Lc and the line Ls1 on a line Ls1 that intersects perpendicularly with the imaginary line Li is the maximum distance, and the maximum width b is the distance at which the distance Dc between the two intersection points Pf and Pg where the line Ls2 and the line Lc intersect is the maximum on a line Ls2 parallel to the imaginary line Li is the maximum distance.

[0037] The ratio h / b is calculated by measuring h and b for one particle or one external toner additive when observing the cross section of the particle or the external toner additive. Examples of h and b are shown in Figures 2A to 2D.

[0038] When the number-average value of the ratio h / b of the maximum height h to the maximum width b is 0.33 or more and 0.80 or less, the toner exhibits improved cleanability and low-temperature fixability even when subjected to continuous mechanical stress. When the number-average value of the ratio h / b is 0.33 or more, the contact area of ​​the fine particles or external toner additives adhered to the surface of the toner particles with the member can be reduced. In addition, it is possible to maintain a constant distance between the toner particles and the member. As a result, the adhesion force between the toner particles and the member is reduced, reducing residual toner, resulting in better initial cleanability. Furthermore, the area of ​​the toner particle surface covered by each fine particle or external toner additive can be reduced, resulting in better low-temperature fixability. Furthermore, when the number-average value of the ratio h / b is 0.80 or less, the fine particles or external toner additives present on the surface of the toner particles can remain adhered to the surface of the toner particles even when subjected to repeated mechanical stress. As a result, migration of the fine particles or external toner additives to the members is suppressed, and the cleaning properties are further maintained even when the fine particles or external toner additives are continuously subjected to mechanical stress.

[0039] The number average value of the ratio h / b can be controlled by the type and number of parts of the monomer of the fine particles or toner external additive, the reaction temperature during polymerization of the monomer, the reaction time, the pH of the reaction medium and reaction system, and the type of dispersant for the monomer and its concentration in the reaction system.

[0040] In the present invention, it is preferable that the fine particles present on the surface of the toner particles contain at least one structure selected from the group consisting of a structure represented by the following formula (D), a structure represented by the following formula (T), and a structure represented by the following formula (Q). (Ra)(Rb)Si(O 1 / 2 )2 formula (D) Rc-Si(O 1 / 2 )3 formula (T) Si(O 1 / 2 )4 formula (Q) (Ra, Rb, and Rc in formulas (D), (T), and (Q) represent organic groups bonded to silicon atoms.)

[0041] In another embodiment of the present invention, the external toner additive preferably contains at least one selected from the group consisting of structures represented by formula (D), formula (T), and formula (Q).

[0042] Furthermore, in another embodiment of the present invention, the fine particles preferably contain at least one structure selected from the group consisting of structures represented by formula (D), formula (T), and formula (Q).

[0043] When the fine particles or external toner additive contain at least one selected from the group consisting of structures represented by formula (D), formula (T), and formula (Q), the initial cleaning property becomes better.

[0044] Of the four valence electrons of the Si atom in formula (D), formula (T), and formula (Q), 0 to 2 are involved in bonding with Ra, Rb, and Rc, and the remaining 2 to 4 are involved in bonding with the O atom. The O atom has two valence electrons both involved in bonding with Si, that is, it forms a siloxane bond (Si-O-Si). Since two Si atoms have one O atom, the siloxane polymer moiety consisting of a siloxane bond is -Si(O 1 / 2 ) *(* is an integer of 2 to 4). The larger the *, the more siloxane bonds there are, and the lower the surface free energy of the microparticles or external toner additives can be maintained. On the other hand, since the organic groups represented by Ra, Rb, and Rc are hydrophobic, the presence of Ra, Rb, and Rc also lowers the surface free energy of the microparticles or external toner additives. In the present invention, the microparticles or external toner additives adhered to the surface of the toner particles come into contact with a member, and therefore, if the surface free energy of the microparticles or external toner additives is lowered, the adhesive force between the microparticles or external toner additives and the member can be maintained low. Therefore, when the microparticles or external toner additives contain at least one structure selected from the group consisting of structures represented by formula (D), formula (T), and formula (Q), the transferability of the toner is improved and initial cleanability is advantageous. More preferably, the microparticles or external toner additives contain a structure represented by formula (T). In this case, the balance between the siloxane polymer moiety and the organic group contained in the fine particles or the external toner additive is appropriate, and thus the initial cleaning property is more effectively exhibited.

[0045] Ra, Rb and Rc are preferably organic groups having 1 to 8 carbon atoms (preferably 1 to 6 carbon atoms), more preferably hydrocarbon groups, and even more preferably alkyl groups.

[0046] Furthermore, the content of the structure represented by formula (D), formula (T), and / or formula (Q) in the fine particles or external toner additive of the present invention is preferably 50 mol % or more, more preferably 70 mol % or more.

[0047] The siloxane polymer moiety (—Si(O 1 / 2 ) * (* is an integer of 2 to 4)) is present in the fine particles or external additives for toner. 29 The presence of Ra, Rb, and Rc in the formula (D) and the formula (T) can be confirmed by Si-NMR measurement. 13 This can be confirmed by C-NMR measurement.

[0048] The toner of the present invention preferably has approximately hemispherical fine particles on the surface of the toner particles in an amount of 0.1 parts by mass or more per 100 parts by mass of toner particles. This improves low-temperature fixability and cleaning properties of the toner before and after continuous mechanical stress. From the viewpoint of low-temperature fixability, it is more preferable that the toner particles have approximately hemispherical fine particles on the surface of the toner particles in an amount of less than 4.0 parts by mass per 100 parts by mass of toner particles. From the viewpoint of preventing component contamination, it is even more preferable that the toner particles have approximately hemispherical fine particles on the surface of the toner particles in an amount of less than 3.0 parts by mass per 100 parts by mass of toner particles.

[0049] The fine particles or toner external additive of the present invention preferably contain a condensation polymer of an organosilicon compound, wherein the organosilicon compound is at least one selected from the group consisting of organosilicon compounds having a structure represented by the following formula (ZD), organosilicon compounds having a structure represented by the following formula (ZT), and organosilicon compounds having a structure represented by the following formula (ZQ). [ka] (In formulas (ZD), (ZT), and (ZQ), Ra, Rb, and Rc represent organic groups bonded to silicon. R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 and R 9 each independently represents a halogen atom, a hydroxy group, an acetoxy group, or an alkoxy group.

[0050] By condensation polymerizing an organosilicon compound having Ra, Rb, and Rc, the hydrophobicity of the fine particles or external toner additive can be improved, and the toner exhibits excellent initial cleaning properties. Ra, Rb, and Rc are synonymous with Ra, Rb, and Rc in the structures represented by formula (D), formula (T), and formula (Q), and are preferably organic groups having 1 to 8 carbon atoms (preferably 1 to 6). Furthermore, Ra, Rb, and Rc are more preferably hydrocarbon groups having 1 to 8 carbon atoms (preferably 1 to 6), and even more preferably alkyl groups having 1 to 8 carbon atoms (preferably 1 to 6).

[0051] Also, R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , and R 9 are each independently a halogen atom, a hydroxy group, an acetoxy group, or an alkoxy group (hereinafter, these are also collectively referred to as "reactive groups"). These reactive groups undergo hydrolysis, addition polymerization, and condensation polymerization to form a crosslinked structure, thereby obtaining fine particles or external toner additives with excellent durability. From the viewpoints of the gentle progress of hydrolysis at room temperature and the ability to deposit on a substrate, R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , and R 9 R is preferably an alkoxy group, more preferably a methoxy group and / or an ethoxy group. 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , and R 9 The hydrolysis, addition polymerization, and condensation polymerization can be controlled by the reaction temperature, reaction time, reaction medium, and pH of the reaction system.

[0052] As a result of hydrolysis, addition polymerization, and condensation polymerization, the content of the condensation polymer of the above-mentioned organosilicon compound in the fine particles or toner external additive is preferably 50 mol% or more, more preferably 70 mol% or more. Furthermore, as described above, it is more preferable to contain a condensation polymer of an organosilicon compound having a structure represented by formula (ZT), because this provides an appropriate balance between the siloxane polymer moiety and the organic group. To obtain a fine particle or an external additive for a toner, two reactive groups (R 1 and R 2 ), an organosilicon compound (bifunctional silane) having three reactive groups (R 3 , R 4 and R 5 ), and an organosilicon compound (trifunctional silane) having four reactive groups (R 6 , R 7 , R 8 and R 9 ) may be used alone or in combination of two or more of the organosilicon compounds (tetrafunctional silanes).

[0053] Examples of organosilicon compounds having a structure represented by formula (ZD) include the following. Dimethyldimethoxysilane, dimethyldiethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane, 3-mercaptopropylmethyldimethoxysilane.

[0054] Examples of organosilicon compounds having a structure represented by formula (ZT) include the following. Trifunctional vinyl silanes such as vinyltrimethoxysilane, vinyltriethoxysilane, vinyldiethoxymethoxysilane, vinylethoxydimethoxysilane, vinyltrichlorosilane, vinylmethoxydichlorosilane, vinylethoxydichlorosilane, vinyldimethoxychlorosilane, vinylmethoxyethoxychlorosilane, vinyldiethoxychlorosilane, vinyltriacetoxysilane, vinyldiacetoxymethoxysilane, vinyldiacetoxyethoxysilane, vinylacetoxydimethoxysilane, vinylacetoxymethoxyethoxysilane, vinylacetoxydiethoxysilane, vinyltrihydroxysilane, vinylmethoxydihydroxysilane, vinylethoxydihydroxysilane, vinyldimethoxyhydroxysilane, vinylethoxymethoxyhydroxysilane, vinyldiethoxyhydroxysilane; allyltrimethoxysilane, allyl Trifunctional allylsilanes such as triethoxysilane, allyldiethoxymethoxysilane, allylethoxydimethoxysilane, allyltrichlorosilane, allylmethoxydichlorosilane, allylethoxydichlorosilane, allyldimethoxychlorosilane, allylmethoxyethoxychlorosilane, allyldiethoxychlorosilane, allyltriacetoxysilane, allyldiacetoxymethoxysilane, allyldiacetoxyethoxysilane, allylacetoxydimethoxysilane, allylacetoxymethoxyethoxysilane, allylacetoxydiethoxysilane, allyltrihydroxysilane, allylmethoxydihydroxysilane, allylethoxydihydroxysilane, allyldimethoxyhydroxysilane, allylethoxymethoxyhydroxysilane, and allyldiethoxyhydroxysilane; trifunctional styrylsilanes such as p-styryltrimethoxysilane;Methyltrimethoxysilane, methyltriethoxysilane, methyldiethoxymethoxysilane, methylethoxydimethoxysilane, methyltrichlorosilane, methylmethoxydichlorosilane, methylethoxydichlorosilane, methyldimethoxychlorosilane, methylmethoxyethoxychlorosilane, methyldiethoxychlorosilane, methyltriacetoxysilane, methyldiacetoxymethoxysilane, methyldiacetoxyethoxysilane, methylacetoxydimethoxysilane, methylacetoxymethoxyethoxysilane, methylacetoxydiethoxysilane Trifunctional methylsilanes such as methyltrihydroxysilane, methylmethoxydihydroxysilane, methylethoxydihydroxysilane, methyldimethoxyhydroxysilane, methylethoxymethoxyhydroxysilane, and methyldiethoxyhydroxysilane; trifunctional ethylsilanes such as ethyltrimethoxysilane, ethyltriethoxysilane, ethyltrichlorosilane, ethyltriacetoxysilane, and ethyltrihydroxysilane; propyltrimethoxysilane, propyltriethoxysilane, propyltrichlorosilane, and propyl Trifunctional propyl silanes such as triacetoxysilane and propyltrihydroxysilane; trifunctional butyl silanes such as butyltrimethoxysilane, butyltriethoxysilane, butyltrichlorosilane, butyltriacetoxysilane and butyltrihydroxysilane; trifunctional hexyl silanes such as hexyltrimethoxysilane, hexyltriethoxysilane, hexyltrichlorosilane, hexyltriacetoxysilane and hexyltrihydroxysilane; phenyltrimethoxysilane, phenyltriethoxysilane, phenyltri Trifunctional phenylsilanes such as chlorosilane, phenyltriacetoxysilane, and phenyltrihydroxysilane; trifunctional epoxysilanes such as 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, and 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane; trifunctional methacrylsilanes such as 3-methacryloxypropyltrimethoxysilane and 3-methacryloxypropyltriethoxysilane; trifunctional acrylicsilanes such as 3-acryloxypropyltrimethoxysilane;Trifunctional aminosilanes such as 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, N-2-(aminoethyl)-3-aminopropyltrimethoxysilane, N-2-(aminoethyl)-3-aminopropyltriethoxysilane, and N-phenyl-3-aminopropyltrimethoxysilane; trifunctional ureidosilanes such as 3-ureidopropyltriethoxysilane; trifunctional 3-chloropropylsilanes such as 3-chloropropyltrimethoxysilane; trifunctional mercaptosilanes such as 3-mercaptopropyltrimethoxysilane and 3-mercaptopropyltriethoxysilane; trifunctional sulfidosilanes such as bis(triethoxysilylpropyl)tetrasulfide; and trifunctional isocyanatesilanes such as 3-isocyanatopropyltriethoxysilane.

[0055] Examples of organosilicon compounds having a structure represented by formula (ZQ) include the following. Tetraalkoxysilanes such as tetramethoxysilane and tetraethoxysilane; tetraalkylcarboxysilanes such as tetraacetoxysilane; and tetrahalosilanes such as tetrachlorosilane.

[0056] In addition to the condensation polymers of the above-mentioned organosilicon compounds, the microparticles or toner external additives may also contain condensation polymers of organosilicon compounds having one reactive group per molecule (monofunctional silanes), and difunctional silanes, trifunctional silanes, and tetrafunctional silanes other than those mentioned above. Examples of these compounds include the following:

[0057] Hexamethyldisilazane, trimethylsilyl chloride, triethylsilyl chloride, triisopropylsilyl chloride, t-butyldimethylsilyl chloride, N,N'-bis(trimethylsilyl)urea, N,O-bis(trimethylsilyl)trifluoroacetamide, trimethylsilyl trifluoromethanesulfonate, 1,3-dichloro-1,1,3,3-tetraisopropyldisiloxane, trimethylsilylacetylene, hexamethyldisilane, tetraisocyanate silane, methyltriisocyanate silane, vinyltriisocyanate silane.

[0058] Furthermore, the fine particles or external toner additive may contain, in addition to the condensation polymer of the organosilicon compound, a condensation polymer of an organotitanium compound and an organoaluminum compound.

[0059] The organic titanium compounds include the following: Titanium methoxide, titanium ethoxide, titanium n-propoxide, tetra-i-propoxytitanium, tetra-n-butoxytitanium, titanium isobutoxide, titanium butoxide dimer, titanium tetra-2-ethylhexoxide, titanium diisopropoxybis(acetylacetonate), titanium tetraacetylacetonate, titanium di-2-ethylhexoxybis(2-ethyl-3-hydroxyhexoxide), titanium diisopropoxybis(ethylacetoacetate), tetrakis(2-ethylhexyloxy)titanium, di-i-propoxybis(acetylacetonato)titanium, titanium lactate, titanium methacrylate isopropoxide, triisopropoxytitanate, titanium methoxypropoxide, titanium stearyl oxide.

[0060] The organic aluminum compounds include the following: Aluminum(III) n-butoxide, aluminum(III) s-butoxide, aluminum(III) s-butoxide bis(ethyl acetoacetate), aluminum(III) t-butoxide, aluminum(III) di-s-butoxide ethyl acetoacetate, aluminum(III) diisopropoxide ethyl acetoacetate, aluminum(III) ethoxide, aluminum(III) ethoxyethoxyethoxide, aluminum hexafluoropentanedionate, aluminum(III) 3-hydroxy-2-methyl-4-pyronate, aluminum(III) isopropoxide, aluminum-9-octadecenyl acetoacetate diisopropoxide, aluminum(III) 2,4-pentanedionate, aluminum phenoxide, aluminum(III) 2,2,6,6-tetramethyl-3,5-heptanedionate.

[0061] These organosilicon compounds, organotitanium compounds, and organoaluminum compounds may be used alone or in combination.

[0062] Specific methods for producing the fine particles or external toner additive of the present invention will be described below, but the methods are not limited thereto.

[0063] The sol-gel process is an example of a method for producing microparticles or external toner additives. The sol-gel process uses metal alkoxides M(OR)n (M: metal, O: oxygen, R: hydrocarbon, n: oxidation state of the metal) as starting materials, which undergo hydrolysis and condensation polymerization in a medium, leading to a sol state and subsequent gelation. When the microparticles or external toner additives contain a structure represented by formula (D), (T), or (Q), an organosilicon compound having a structure represented by formula (ZD), (ZT), or (ZQ) can be used as the metal alkoxide M(OR)n. This process is used to synthesize glass, ceramics, organic-inorganic hybrids, and nanocomposites. This manufacturing method allows functional materials of various shapes, such as surface layers, fibers, bulk materials, and microparticles, to be produced from the liquid phase at low temperatures. Furthermore, because the sol-gel process starts from a solution and forms materials by gelling the solution, it is possible to create a variety of microstructures and shapes. The microstructure and shape can be adjusted by the type and number of parts of the monomer, the reaction temperature, the reaction time, the pH of the reaction medium and the reaction system, and the type and concentration of the dispersant.

[0064] It is generally known that the bonding state of the metalloxane bond (MOM) formed in a sol-gel reaction varies depending on the acidity of the reaction medium. Specifically, when the reaction medium is acidic, a hydrogen ion electrophilically attaches to the oxygen of one reactive group (e.g., an alkoxy group). Next, an oxygen atom in a water molecule coordinates to the metal atom, forming a hydroxyl group through a substitution reaction. When sufficient water is present, one hydrogen ion attacks one oxygen of a reactive group (e.g., an alkoxy group). Therefore, as the hydrogen ion content and reactive groups in the medium decrease as the reaction progresses, the substitution reaction to form a hydroxyl group slows. Therefore, a condensation polymerization reaction occurs before all of the reactive groups attached to the metal atom are hydrolyzed, making it relatively easy to form one-dimensional linear polymers or two-dimensional polymers.

[0065] On the other hand, when the medium is alkaline, hydroxide ions are added to the metal atom via a pentacoordinated intermediate. This allows all reactive groups (e.g., alkoxy groups) to be easily eliminated and replaced with hydroxy groups. In particular, when a metal compound with three or more reactive groups on the same metal atom is used, hydrolysis and condensation polymerization occur three-dimensionally, forming an organometallic polymer with many three-dimensional crosslinks. Furthermore, this reaction is completed in a short time.

[0066] Therefore, to form microparticles or external toner additives made of organometallic polymers, it is preferable to carry out the sol-gel reaction in an alkaline reaction medium, and when producing in an aqueous medium, specifically, a pH of 8.0 or higher is preferable, which allows the formation of microparticles or external toner additives with higher strength and durability.

[0067] Examples of aqueous media include the following: Water, or a mixed solvent of water and an alcohol such as methanol, ethanol, or propanol.

[0068] Furthermore, in order to give the fine particles or external toner additive of the present invention a solid and approximately hemispherical shape and to control the number average value of the longest diameter w of the approximately flat surface to 10 nm or more and 400 nm or less, it is preferable to produce them by dispersing an organometallic compound and a base material in a medium.

[0069] First, the substrate is dispersed in a medium to obtain a substrate dispersion. It is preferable to disperse the substrate at a concentration such that the solid content of the substrate is 5% by mass or more and 40% by mass or less relative to the total amount of the substrate dispersion. A dispersion stabilizer, as described below, may be used as appropriate. It is also preferable to adjust the temperature of the substrate dispersion to 35°C or higher. It is also preferable to adjust the pH of the substrate dispersion to a pH that does not favor condensation of the organometallic compound. The pH at which condensation of the organometallic compound favors condensation varies depending on the type of organometallic compound, but it is preferable to adjust the pH to within ±0.5 of the pH at which the reaction is most favorable. It is not necessary to completely disperse the substrate in the medium. For example, if the substrate is a flat plate, the plate may be propped up in a reaction vessel and condensation may proceed on the substrate.

[0070] Next, it is preferable to use an organometallic compound that has been subjected to hydrolysis treatment. For example, the hydrolysis treatment of the organometallic compound may be carried out in a separate vessel. The concentration of the organometallic compound charged in the hydrolysis treatment is preferably 40 to 500 parts by mass of water from which ions have been removed, such as ion-exchanged water or RO water, and more preferably 100 to 400 parts by mass of water, assuming that the amount of the organometallic compound is 100 parts by mass. The conditions for the hydrolysis treatment are preferably a pH of 1.0 to 7.0, a temperature of 15 to 80°C, and a time of 1 to 600 minutes.

[0071] The hydrolyzed organometallic compound is then added to the base dispersion. The base dispersion and the hydrolyzed solution of the organometallic compound are mixed by stirring and maintained at a temperature of preferably 35°C or higher for 3 to 120 minutes. The pH is then adjusted to a level suitable for condensation (preferably pH 6.0 or higher or pH 3.0 or lower, more preferably pH 8.0 or higher), and the organometallic compound is rapidly condensed. The temperature is then maintained at a temperature of preferably 35°C or higher for 60 minutes or longer, forming microparticles or external toner additives made of organometallic polymers such as organosilicon polymers on the surface of the base material.

[0072] The substrate with the microparticles or external toner additives formed on its surface is then stirred and mixed with a medium in which the substrate has a high solubility and the microparticles or external toner additives have a low solubility, thereby dissolving only the substrate. Because solubility varies depending on the substrate material and the type of medium, the solids concentration of the substrate, the stirring time, and the temperature are set within a range in which the substrate is sufficiently dissolved. The microparticles or external toner additives are then separated by a method such as centrifugation and dried to obtain solid, approximately hemispherical microparticles. If the substrate has a low solubility, the microparticles or external toner additives may be separated by simply lifting the substrate out of the reaction vessel and peeling them off the substrate.

[0073] The substrate used in producing the microparticles or external toner additive of the present invention is preferably a flat plate of metal, glass, ceramic, or the like, or resin particles, from the viewpoint of separability from the microparticles or external toner additive. Among these, resin particles with a low degree of crosslinking and solubility are particularly preferred. When the size of the resin particles is 1 to 100 μm, the particle size of the substrate is several tens of times or more the particle size of the microparticles or external toner additive, which facilitates the production of approximately hemispherical microparticles or external toner additives having approximately flat and curved surfaces, and is therefore preferred. The material of the resin particles is not particularly limited, but polymethyl methacrylate (PMMA) particles, polystyrene microparticles, etc., produced by soap-free emulsion polymerization or the like are preferred.

[0074] When dispersing the organometallic compound and the substrate in the medium, known surfactants, inorganic and organic dispersants may be used as dispersion stabilizers.

[0075] The surfactants include the following: (1) Anionic surfactants: alkyl sulfates such as sodium lauryl sulfate; polyoxyethylene alkyl ether sulfates such as sodium polyoxyethylene lauryl ether sulfate; sulfonates such as sodium dodecylbenzenesulfonate and sodium alkylnaphthalenesulfonate; higher fatty acid salts such as sodium stearate and sodium laurate. (2) Cationic surfactants: quaternary ammonium salts such as dodecyl ammonium bromide, dodecyl trimethyl ammonium bromide, dodecyl pyridinium chloride, dodecyl pyridinium bromide, hexadecyl trimethyl ammonium bromide, lauryl trimethyl ammonium chloride, and alkyl benzyl dimethyl ammonium chloride. (3) Nonionic surfactants: polyoxyethylene alkyl ethers such as polyoxyethylene lauryl ether and polyoxyethylene oleyl ether; polyoxyalkylene derivatives such as polyoxyethylene alkylene alkyl ethers; sorbitan fatty acid esters such as sorbitan monolaurate and sorbitan monostearate; glycerin fatty acid esters such as glycerol monostearate; polyoxyethylene fatty acid esters such as polyethylene glycol monolaurate.

[0076] Other examples of inorganic dispersants include the following: trivalent aluminum salts such as aluminum chloride, aluminum sulfate, aluminum hydroxide, aluminum phosphate, and polyaluminum chloride; trivalent and divalent iron salts such as iron(III) chloride, iron(III) sulfate, iron(III) hydroxide, iron(II) chloride, iron(II) sulfate, iron(II) hydroxide, polyiron sulfate, and polyiron silica; divalent magnesium salts such as magnesium chloride, magnesium sulfate, magnesium hydroxide, magnesium phosphate, and magnesium carbonate; divalent calcium salts such as calcium chloride, calcium sulfate, tricalcium phosphate, calcium hydrogen phosphate, calcium dihydrogen phosphate, calcium hydroxide, hydroxyapatite, calcium carbonate, and calcium metasilicate; divalent cobalt salts such as cobalt chloride and cobalt sulfate; divalent zinc salts such as zinc phosphate; divalent barium salts such as barium sulfate; silicate minerals such as bentonite; and metal oxides such as silica and alumina.

[0077] Examples of organic dispersants include the following: Polyvinyl alcohol, gelatin, methylcellulose, methylhydroxypropylcellulose, ethylcellulose, sodium salt of carboxymethylcellulose, starch.

[0078] These dispersion stabilizers are appropriately selected depending on the material of the substrate and the interaction with the organometallic compound. These dispersion stabilizers may be used alone or in combination.

[0079] Next, the components contained in the toner particles will be described. The toner particles contained in the toner of the present invention contain a binder resin, a colorant and other components.

[0080] The binder resin may be a resin (preferably amorphous) that is generally used as a binder resin for toner. Specifically, styrene-acrylic resins (styrene-acrylic acid ester copolymers, styrene-methacrylic acid ester copolymers, etc.), polyester resins, epoxy resins, polyurethane resins, polyamide resins, cellulose resins, polyether resins, styrene-butadiene copolymers, mixed resins or composite resins thereof, etc. may be used.

[0081] Examples of the polymerizable monomer in the styrene-acrylic resin include the vinyl polymerizable monomers shown below. Styrene; styrene derivatives such as α-methylstyrene, β-methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, 2,4-dimethylstyrene, pn-butylstyrene, p-tert-butylstyrene, pn-hexylstyrene, pn-octylstyrene, pn-nonylstyrene, pn-decylstyrene, pn-dodecylstyrene, p-methoxystyrene, and p-phenylstyrene; methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, tert-butyl acrylate, n-amyl acrylate, n-hexyl acrylate, 2-ethylhexyl acrylate, n-octyl acrylate, n-nonyl acrylate, cyclohexyl acrylate, benzyl acrylate, dimethyl phosphate ethyl acrylate, diethyl phosphate ethyl acrylate, and dibutyl phosphate ethyl acrylate. acrylate, 2-benzoyloxyethyl acrylate, and other acrylic polymerizable monomers; methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, tert-butyl methacrylate, n-amyl methacrylate, n-hexyl methacrylate, 2-ethylhexyl methacrylate, n-octyl methacrylate, n-nonyl methacrylate, diethyl phosphate ethyl methacrylate, and dibutyl phosphate ethyl methacrylate, and other methacrylic polymerizable monomers; methylene aliphatic monocarboxylic acid esters; vinyl esters such as vinyl acetate, vinyl propionate, vinyl benzoate, vinyl butyrate, vinyl benzoate, and vinyl formate; vinyl ethers such as vinyl methyl ether, vinyl ethyl ether, and vinyl isobutyl ether; vinyl methyl ketone, vinyl hexyl ketone, and vinyl isopropyl ketone.

[0082] A polymerization initiator may be added during polymerization of the polymerizable monomer. Examples of the polymerization initiator include azo or diazo polymerization initiators such as 2,2'-azobis-(2,4-dimethylvaleronitrile), 2,2'-azobisisobutyronitrile, 1,1'-azobis(cyclohexane-1-carbonitrile), 2,2'-azobis-4-methoxy-2,4-dimethylvaleronitrile, and azobisisobutyronitrile; and peroxide polymerization initiators such as benzoyl peroxide, methyl ethyl ketone peroxide, diisopropyl peroxycarbonate, cumene hydroperoxide, 2,4-dichlorobenzoyl peroxide, and lauroyl peroxide. These polymerization initiators are preferably added in an amount of 0.5 to 30.0 parts by mass per 100 parts by mass of the total of the polymerizable monomers, and may be used alone or in combination.

[0083] In order to control the molecular weight of the binder resin constituting the toner particles, a chain transfer agent may be added during polymerization of the polymerizable monomer. The weight average molecular weight of the binder resin is preferably 5,000 or more and 100,000 or less. The amount of the chain transfer agent added is preferably 0.001 to 15,000 parts by mass per 100 parts by mass of the total of the polymerizable monomers.

[0084] In order to control the molecular weight of the binder resin that constitutes the toner particles, a crosslinking agent may be added during polymerization of the polymerizable monomer. Examples of crosslinking agents include: divinylbenzene, bis(4-acryloxypolyethoxyphenyl)propane, ethylene glycol diacrylate, 1,3-butylene glycol diacrylate, 1,4-butanediol diacrylate, 1,5-pentanediol diacrylate, 1,6-hexanediol diacrylate, neopentyl glycol diacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol #200, #400, and #600 diacrylates, dipropylene glycol diacrylate, polypropylene glycol diacrylate, polyester-type diacrylates, and acrylates obtained by replacing the above acrylates with methacrylates. Examples of polyfunctional crosslinking monomers include: Pentaerythritol triacrylate, trimethylolethane triacrylate, trimethylolpropane triacrylate, tetramethylolmethane tetraacrylate, oligoester acrylate and its methacrylate, 2,2-bis(4-methacryloxypolyethoxyphenyl)propane, diallyl phthalate, triallyl cyanurate, triallyl isocyanurate, triallyl trimellitate, diaryl chlorendate. The preferred amount of crosslinking agent added is 0.001 to 15,000 parts by mass per 100 parts by mass of the total of the polymerizable monomers.

[0085] As the polyester resin, a resin obtained by polycondensation of a carboxylic acid component and an alcohol component can be used.

[0086] Examples of carboxylic acid components include oxalic acid, succinic acid, glutaric acid, maleic acid, adipic acid, β-methyladipic acid, azelaic acid, sebacic acid, nonanedicarboxylic acid, decanedicarboxylic acid, undecanedicarboxylic acid, dodecanedicarboxylic acid, fumaric acid, citraconic acid, diglycolic acid, cyclohexane-3,5-diene-1,2-carboxylic acid, hexahydroterephthalic acid, malonic acid, pimelic acid, suberic acid, phthalic acid, isophthalic acid, terephthalic acid, tetrachlorophthalic acid, chlorophthalic acid, nitrophthalic acid, p-carboxyphenylacetic acid, p-phenylenediacetic acid, m-phenylenediacetic acid, o-phenylenediacetic acid, diphenylacetic acid, di Dicarboxylic acids such as phenyl-p,p'-dicarboxylic acid, naphthalene-1,4-dicarboxylic acid, naphthalene-1,5-dicarboxylic acid, naphthalene-2,6-dicarboxylic acid, anthracenedicarboxylic acid, and cyclohexanedicarboxylic acid; and polycarboxylic acids such as trimellitic acid, trimesic acid, pyromellitic acid, naphthalenetricarboxylic acid, naphthalenetetracarboxylic acid, pyrenetricarboxylic acid, pyrenetetracarboxylic acid, itaconic acid, glutaconic acid, n-dodecylsuccinic acid, n-dodecenylsuccinic acid, isododecylsuccinic acid, isododecenylsuccinic acid, n-octylsuccinic acid, and n-octenylsuccinic acid. These may be used alone or in combination of two or more.

[0087] Examples of alcohol components include ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, 1,12-dodecanediol, 1,13-tridecanediol, 1,14-tetradecanediol, 1,18-octadecanediol, 1,14-eicosanedecanediol, diethylene glycol, triethylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene ether glycol, 1,4-cyclohexanediol ... Diols such as hexanedimethanol, 1,4-butenediol, neopentyl glycol, 1,4-cyclohexanediol, polytetramethylene glycol, hydrogenated bisphenol A, bisphenol A, bisphenol F, bisphenol S, and alkylene oxide (ethylene oxide, propylene oxide, butylene oxide, etc.) adducts of the above bisphenols; and polyols such as glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, hexamethylolmelamine, hexaethylolmelamine, tetramethylolbenzoguanamine, tetraethylolbenzoguanamine, sorbitol, trisphenol PA, phenol novolac, cresol novolac, and alkylene oxide adducts of the above trivalent or higher polyphenols. These may be used alone or in combination of two or more. The polyester resin may also be a polyester resin containing a urea group.

[0088] The colorant is not particularly limited, and the following known colorants can be used. Yellow pigments include condensed azo compounds such as yellow iron oxide, Naples Yellow, Naphthol Yellow S, Hansa Yellow G, Hansa Yellow 10G, Benzidine Yellow G, Benzidine Yellow GR, Quinoline Yellow Lake, Permanent Yellow NCG, and Tartrazine Lake, as well as isoindolinone compounds, anthraquinone compounds, azo metal complexes, methine compounds, and arylamide compounds. Specific examples include CI Pigment Yellow 12, 13, 14, 15, 17, 62, 74, 83, 93, 94, 95, 109, 110, 111, 128, 129, 147, 155, 168, and 180.

[0089] Orange pigments include: Permanent Orange GTR, Pyrazolone Orange, Balkan Orange, Benzidine Orange G, Induthrene Brilliant Orange RK, and Induthrene Brilliant Orange GK.

[0090] Red pigments include condensed azo compounds such as red iron oxide, permanent red 4R, lithol red, pyrazolone red, Watching Red calcium salt, lake red C, lake red D, brilliant carmine 6B, brilliant carmine 3B, eosin lake, rhodamine lake B, and alizarin lake, as well as diketopyrrolopyrrole compounds, anthraquinone compounds, quinacridone compounds, basic dye lake compounds, naphthol compounds, benzimidazolone compounds, thioindigo compounds, and perylene compounds. Specific examples include 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.

[0091] Examples of blue pigments include alkali blue lake, Victoria blue lake, phthalocyanine blue, metal-free phthalocyanine blue, phthalocyanine blue partial chloride, copper phthalocyanine compounds such as fast sky blue and indanthrene blue BG, and their derivatives, anthraquinone compounds, and basic dye lake compounds. Specific examples include CI Pigment Blue 1, 7, 15, 15:1, 15:2, 15:3, 15:4, 60, 62, and 66.

[0092] Purple pigments include Fast Violet B and Methyl Violet Lake. Green pigments include Pigment Green B, Malachite Green Lake, and Final Yellow Green G. White pigments include zinc white, titanium oxide, antimony white, and zinc sulfide. Examples of black pigments include carbon black, aniline black, non-magnetic ferrite, magnetite, and those toned to black using the above-mentioned yellow colorants, red colorants, and blue colorants. These colorants can be used alone or in combination, or in the form of a solid solution.

[0093] The content of the colorant is preferably 3.0 parts by mass or more and 15.0 parts by mass or less per 100 parts by mass of the binder resin or the polymerizable monomers that form the binder resin.

[0094] The toner may contain a release agent. The release agent is not particularly limited, and the following known release agents can be used: petroleum waxes and derivatives thereof, such as paraffin wax, microcrystalline wax, and petrolatum; montan wax and derivatives thereof; hydrocarbon waxes and derivatives thereof produced by the Fischer-Tropsch process; polyolefin waxes and derivatives thereof, such as polyethylene and polypropylene; natural waxes and derivatives thereof, such as carnauba wax and candelilla wax; higher aliphatic alcohols; fatty acids, such as stearic acid and palmitic acid, or compounds thereof; acid amide waxes; ester waxes; ketones; hydrogenated castor oil and derivatives thereof; vegetable waxes; animal waxes; and silicone resins. Derivatives include oxides, block copolymers with vinyl monomers, and graft-modified products. These can be used alone or in combination. The content of the release agent is preferably 5.0 parts by mass or more and 30.0 parts by mass or less relative to 100 parts by mass of the binder resin or the polymerizable monomers that form the binder resin.

[0095] The toner may contain a crystalline resin. The crystalline resin is not particularly limited, and known resins may be used. Specific examples include crystalline polyester resins and crystalline acrylic resins. The crystalline resin may be a block polymer having a crystalline portion and an amorphous portion.

[0096] The toner may contain a charge control agent, and known charge control agents can be used. The amount of the charge control agent added is preferably 0.01 to 10.00 parts by mass per 100 parts by mass of the binder resin or the polymerizable monomers that form the binder resin.

[0097] In addition to the fine particles of the present invention, various organic or inorganic fine powders may be externally added to the toner particles as required.

[0098] As the organic fine powder or inorganic fine powder, for example, the following can be used. (1) Fluidity imparting agents: silica, alumina, titanium oxide, carbon black and carbon fluoride. (2) Abrasives: metal oxides (e.g., strontium titanate, cerium oxide, alumina, magnesium oxide, chromium oxide), nitrides (e.g., silicon nitride), carbides (e.g., silicon carbide), metal salts (e.g., calcium sulfate, barium sulfate, calcium carbonate). (3) Lubricants: Fluorine-based resin powder (for example, vinylidene fluoride, polytetrafluoroethylene), fatty acid metal salts (for example, zinc stearate, calcium stearate). (4) Charge control particles: metal oxides (for example, tin oxide, titanium oxide, zinc oxide, silica, alumina), carbon black.

[0099] The organic or inorganic fine powder may be surface-treated to improve the fluidity of the toner and to uniformly charge the toner particles. Examples of the treatment agent for the hydrophobic treatment of the organic or inorganic fine powder include unmodified silicone varnish, various modified silicone varnishes, unmodified silicone oil, various modified silicone oils, silane compounds, silane coupling agents, other organosilicon compounds, and organotitanium compounds. These treatment agents may be used alone or in combination.

[0100] An example of a method for producing toner particles will be given below. (1) Suspension polymerization method: A polymerizable monomer composition containing a polymerizable monomer capable of producing a binder resin, a release agent, and, if necessary, a colorant, etc., is granulated in an aqueous medium, and the polymerizable monomer is polymerized to obtain toner particles. (2) Pulverization method: A binder resin, a release agent, and, if necessary, a colorant, etc. are melted and kneaded, and then pulverized to obtain toner particles. (3) Dissolution suspension method: A binder resin, a release agent, and, if necessary, a colorant, etc. are dissolved in an organic solvent to produce an organic phase dispersion, which is then suspended in an aqueous medium, granulated, and polymerized, followed by removal of the organic solvent to obtain toner particles. (4) Emulsion aggregation polymerization method: Binder resin particles, release agent particles, and optionally particles of a colorant, etc. are aggregated and associated in an aqueous medium to obtain toner particles. Examples of aqueous media include the following: water; mixed solvents of water and alcohols such as methanol, ethanol, and propanol;

[0101] Various measurement methods related to the present invention will be described below. <Method for confirming that fine particles or external toner additives are solid> The solidity of the fine particles or external toner additives can be confirmed using a scanning transmission electron microscope (STEM). The sample for STEM observation is prepared as follows. First, toner, fine particles, or external toner additives are spread onto a cover glass (Matsunami Glass Co., Ltd., square cover glass; square No. 1) to form a single layer. Then, using an osmium plasma coater (Filgen, OPC80T), an Os film (5 nm) and a naphthalene film (20 nm) are applied to the toner, fine particles, or external toner additives as a protective film. Next, a PTFE tube (Φ1.5mm x Φ3mm x 3mm) is filled with photocurable resin D800 (JEOL Ltd.), and a cover glass is gently placed on top of the tube so that the toner, fine particles, or external toner additive is in contact with the photocurable resin D800. After irradiating the resin with light in this state to cure it, the cover glass and tube are removed to form a cylindrical resin with the toner, fine particles, or external toner additive embedded in its outermost surface. Using an ultrasonic ultramicrotome (Leica, UC7), the cylindrical resin is cut from the outermost surface at a cutting speed of 0.6 mm / s to expose the cross section of the center of the microparticle or external toner additive. Next, it is cut to a film thickness of 100 nm to prepare a thin section sample of the cross section of the microparticle or external toner additive. By cutting in this manner, the cross section of the center of the microparticle or external toner additive can be obtained.

[0102] The STEM equipment used, as well as the observation method and conditions, are as follows. Equipment: FEI Tecnai TF20XT transmission electron microscope The STEM probe size is 1 nm, and images are acquired at an image size of 1024 x 1024 pixels. Also, for bright-field images, adjust the Contrast on the Detector Control panel to 1425, Brightness to 3750, and the Contrast on the Image Control panel to 0.0, Brightness to 0.5, and Gamma to 1.00. Images are acquired at a magnification of 100,000 to 200,000 times. If the STEM image shows that the interior of the particle or external toner additive is filled with solid and not hollow, it is determined to be solid. Furthermore, even if the particle or external toner additive is solid, in the present invention, the particle or external toner additive is considered hollow if the ratio df / h is greater than 0.10. For example, the particle or external toner additive shown in Figures 2A, 2B, and 2D is solid, while the particle or external toner additive shown in Figure 2C is hollow.

[0103] <Method for confirming that the fine particles or external toner additives are approximately hemispherical> The confirmation that the fine particles or external toner additives are substantially hemispherical is carried out using a scanning transmission electron microscope (STEM). The preparation of the sample for STEM observation, the STEM equipment, and the observation method and conditions are as described above. From the obtained STEM image, the number average values ​​of the ratio df / h, ratio l1 / l2, and ratio s1 / s2 of the fine particles or external toner additives are calculated using image processing software ImageJ (developed by Wayne Rasband). The calculation method is explained below with reference to Figures 2A to 2D.

[0104] First, use the straight line tool (Straight Line) on the toolbar to select the scale bar in the observation condition display area at the bottom of the image. Then, select Set Scale from the Analyze menu. A new window will open, and the pixel distance of the selected line will be entered in the Distance in Pixels field. Enter the scale bar value (e.g., 100) in the Known Distance field of the window, enter the scale bar unit (e.g., nm) in the Unit of Measurement field, and click OK to complete the scale setting.

[0105] Next, select ROI Manager from Tools in the Analyze menu, and check Show All and Labels in the newly opened ROI Manager window. Next, use the straight line tool (Straight Line) on the toolbar to draw an imaginary line Li connecting two intersections Pa and Pb of line Lf derived from the approximate plane of the particulate matter or toner external additive and line Lc derived from the curved surface, as shown in Figures 2A to 2D. In this state, select Add in the ROI Manager window. Next, draw a line that is perpendicular to imaginary line Li, such that the distance between the intersection with imaginary line Li and the intersection with line Lf derived from the approximate plane of the particulate matter or toner external additive is the maximum length df, and select Add. Furthermore, a line Ls1 perpendicular to the virtual line Li is drawn, and either one of the distance Da between the intersection Pc of the virtual line Li and the line Ls1 and the intersection Pe of the line Lc derived from the curved surface and the line Ls1, or the distance Db between the intersection Pd of the line Lf derived from the approximately flat surface and the line Ls1 and the intersection Pe of the line Lc derived from the curved surface and the line Ls1 is drawn, and after selecting Add, the analysis is performed by selecting Measure in the ROI Manager window. The length (Length) corresponding to the maximum length df and the maximum height h is obtained from the newly opened Results window, and the ratio df / h is calculated.

[0106] Also, using the elliptical selections on the toolbar, draw an ellipse e1 that passes through two intersections of the approximate flat surface and the curved surface of the microparticle or toner external additive, circumscribing the curved surface of the microparticle or toner external additive, and an ellipse e2 that passes through two intersections of the approximate flat surface and the curved surface of the microparticle or toner external additive, and inscribes the curved surface of the microparticle or toner external additive, as shown in Figures 2E and 2F. Then, select Add in the ROI Manager window. Next, use the straight line tool on the toolbar to draw a line that represents the major axis l1 and minor axis s1 of ellipse e1, and the major axis l2 and minor axis s2 of ellipse e2, as shown in Figures 2G and 2H, and select Add. Next, select Measure in the ROI Manager window to perform the analysis. From the newly opened Results window, obtain the lengths corresponding to the major axis l1 of ellipse e1, the major axis l2 of ellipse e2, the minor axis s1 of ellipse e1, and the minor axis s2 of ellipse e2, and calculate the ratios l1 / l2 and s1 / s2.

[0107] The above procedure is carried out for 100 particles of the fine particles or external toner additives to be evaluated, and the number average values ​​of the ratio df / h, the ratio l1 / l2, and the ratio s1 / s2 are calculated. Microparticles or external toner additives that have been confirmed by the above method to satisfy the following two conditions are determined to be approximately hemispherical: (1) the number average value of df / h is 0.00 or more and 0.10 or less, and (2) the number average value of l1 / l2 is 0.90 or more and 1.10 or less, and the number average value of s1 / s2 is 0.90 or more and 1.10 or less.

[0108] <Method for calculating the number average value of the longest diameter w of the approximately flat surface of fine particles or external toner additives> The number average value of the longest diameter w of the fine particles or external toner additives on the approximately flat surface is calculated using a scanning electron microscope (SEM). The SEM equipment, observation method and conditions are as follows: Apparatus: Ultra-high resolution field emission scanning electron microscope S-4800 manufactured by Hitachi High-Technologies Corporation (hereinafter referred to as "S-4800")

[0109] (1) Sample preparation A thin layer of conductive paste (product number 16053, manufactured by TED PELLA, Inc., PELCO Colloidal Graphite, isopropanol base) is applied to a sample stage (aluminum sample stage, 15 mm x 6 mm), and toner, fine particles, or external toner additives are sprayed onto it. After removing excess fine particles or external toner additives from the sample stage with air blowing, platinum is evaporated at 15 mA for 15 seconds. The sample stage is then placed in the sample holder, and the height of the sample stage is adjusted to 30 mm using the sample height gauge.

[0110] (2) S-4800 observation condition setting Pour liquid nitrogen into the anti-contamination trap attached to the S-4800 housing until it overflows and leave it for 30 minutes. Start the S-4800's "PC-SEM" and perform flushing (cleaning the FE chip, which is the electron source). Click the accelerating voltage display area on the control panel on the screen and press the [Flushing] button to open the flushing execution dialog. Confirm that the flushing intensity is 2 and execute it. Confirm that the emission current due to flushing is 20-40 μA. Insert the sample holder into the sample chamber of the S-4800 housing. Press [Origin] on the control panel to move the sample holder to the observation position. Click the accelerating voltage display to open the HV setting dialog, and set the accelerating voltage to [2.0 kV] and the emission current to [10 μA]. In the [Basic] tab of the operation panel, set the signal selection to [SE], select the SE detector to [Bottom (L)], and set the mode to observe backscattered electron images. Also in the [Basic] tab of the operation panel, set the probe current in the electron optical system condition block to [Normal], the focus mode to [UHR], and the WD to [8.0 mm]. Press the [ON] button in the accelerating voltage display on the control panel to apply the accelerating voltage.

[0111] (3) Focus adjustment Drag within the magnification display area on the control panel to set the magnification to 5000 (5k). Rotate the focus knob [COARSE] on the operation panel to adjust the aperture alignment once the image is in focus to a certain extent. Click [Align] on the control panel to display the alignment dialog and select [Beam]. Rotate the STIGMA / ALIGNMENT knobs (X, Y) on the operation panel to move the displayed beam to the center of the concentric circle. Next, select [Aperture] and turn the STIGMA / ALIGNMENT knobs (X, Y) one by one to stop the image movement or adjust it so that it moves as little as possible. Close the aperture dialog and use autofocus to adjust the focus. Repeat this operation two more times to adjust the focus. With the midpoint of the maximum diameter of the observed particle aligned with the center of the measurement screen, drag within the magnification display area on the control panel to set the magnification to 10,000 (10k). Rotate the focus knob [COARSE] on the operation panel to achieve a certain degree of focus, then adjust the aperture alignment. Click [Align] on the control panel to display the alignment dialog, and select [Beam]. Rotate the STIGMA / ALIGNMENT knobs (X, Y) on the operation panel to move the displayed beam to the center of the concentric circle. Next, select [Aperture] and turn the STIGMA / ALIGNMENT knobs (X, Y) one by one to stop the image movement or adjust it so that it moves as little as possible. Close the Aperture dialog and use autofocus to adjust the focus. Then, set the magnification to 50,000 (50k) and adjust the focus using the focus knob and STIGMA / ALIGNMENT knob as above, then use autofocus to adjust the focus again. Repeat this operation to adjust the focus.

[0112] (4) Save image Adjust the brightness in ABC mode, set the size to 640 x 480 pixels, and the magnification to 10,000 to 50,000 (10 to 50k) times, and capture and save an image of the fine particles or external toner additives on the surface of the toner particles, or the fine particles or external toner additives on the surface of the sample stage, from above (a direction in which a roughly flat projection of the fine particles or external toner additives can be observed). From the obtained SEM image, the number average value of the longest diameter w of the approximately flat surface of the fine particles or external toner additive is calculated using image processing software ImageJ (developed by Wayne Rasband). The scale is set as described above, and the number average value of the longest diameter w of the approximately flat surface of the fine particles or external toner additive is calculated using the following procedure. Select Set Measurements from the Analyze menu and check Feret's diameter. Also, select ROI Manager from Tools in the Analyze menu and check Show All and Labels in the newly opened ROI Manager window. Next, use the elliptical selections tool on the toolbar to approximate the approximate plane of one particle or toner additive with an ellipse, as shown in Figure 3. Then, select Add in the ROI Manager window. Similarly, approximate the approximate plane of other particles or toner additives with an ellipse and select Add. After repeating this process for all particles or toner additives in the image, select Measure in the ROI Manager window to perform the analysis. Obtain the longest diameter w(Feret) of the approximate plane of each particle or toner additive from the newly opened Results window. The longest diameter w of the approximate plane of each particle or toner additive obtained in this way is the distance between the longest straight line connecting any two points on the periphery of the approximate plane of the particle or toner additive. The above procedure is carried out for 100 particles to be evaluated, and the number average value of the longest diameter w of the approximately flat surface of the particles or external toner additive is calculated.

[0113] <Method for confirming whether or not roughly flat surfaces of fine particles are observed on the surface of toner particles> Whether or not a substantially flat surface of the fine particles is observed on the surface of the toner particles is determined using a scanning electron microscope (SEM). The SEM device, observation method and conditions are the same as those described above, except that the surface of the toner particles is observed from one arbitrary direction and an image is obtained. From the obtained SEM image, the angle of a microparticle when its approximate plane is in contact with the surface of a toner particle is defined as 0°, and the percentage of microparticles with an angle greater than 90° and less than 270° is calculated relative to the total number of microparticles present on the surface of a toner particle. 200 microparticles present on the surface of a toner particle are counted. Figure 4 shows an example of the angles of microparticles when the surface of a toner particle is viewed from any one direction. If it is confirmed using the above method that the number of microparticles with an angle greater than 90° but less than 270° is 1.0% or more of the microparticles present on the surface of the toner particles, it is determined that an approximately flat surface of the microparticles has been observed on the surface of the toner particles.

[0114] <Method for calculating the number average value of the ratio h / b of maximum height h to maximum width b> The number average value of the ratio h / b of the maximum height h to the maximum width b is calculated using a scanning transmission electron microscope (STEM). The preparation of the sample for STEM observation, the STEM equipment, and the observation method and conditions are as described above.

[0115] From the obtained STEM image, the number average value of the ratio h / b of the fine particles or external toner additives is calculated using the image processing software ImageJ (developed by Wayne Rasband). After setting the scale as described above, the subsequent procedure is as follows. Select ROI Manager from Tools in the Analyze menu and check Show All and Labels in the newly opened ROI Manager window. Next, use the straight line tool (Straight Line) on the toolbar to draw a line Ls1 that gives the maximum height h, as described above, as shown in Figures 2A-2D. In this state, select Add in the ROI Manager window. Next, as shown in Figures 2A-2D, draw a line Ls2 that is perpendicular to the line Ls1 that gives the maximum height h and parallel to the virtual line Li, such that the distance Dc between the two intersection points Pf and Pg where line Ls2 intersects with the line Lc derived from the curved surface is the maximum width b. Select Add, then select Measure in the ROI Manager window to perform the analysis. Obtain the lengths (Length) corresponding to the maximum height h and maximum width b from the newly opened Results window, and calculate the ratio h / b. The above procedure is carried out for 100 particles of the fine particles or external toner additives to be evaluated, and the number average value of the ratio h / b is calculated.

[0116] <Method for confirming the structures represented by formula (D), formula (T), and formula (Q)> Whether the fine particles or external toner additive of the present invention contain the structures represented by formula (D), formula (T), and formula (Q) can be confirmed using a nuclear magnetic resonance (NMR) spectrometer. The sample for NMR measurement is either fine particles or an external toner additive, which is used as is. In the case of toner, the sample is prepared by separating the fine particles, for example, as follows. A concentrated sucrose solution was prepared by adding 160 g of sucrose (Kishida Chemical) to 100 mL of ion-exchanged water and dissolving it in a hot water bath. A 50 mL centrifuge tube was charged with 31 g of the concentrated sucrose solution and 6 mL of Contaminon N (a 10% aqueous solution of a pH 7 neutral detergent for cleaning precision measuring instruments, consisting of nonionic surfactants, anionic surfactants, and organic builders, manufactured by Wako Pure Chemical Industries, Ltd.). 1.0 g of toner was added and the toner clumps were broken down using a spatula or similar tool. The centrifuge tube was shaken at 300 strokes per minute (spm) for 20 minutes in a shaker (product name: AS-1N, sold by AS ONE Corporation). After shaking, the solution was transferred to a 50 mL glass tube for a swing-out rotor and centrifuged at 3500 rpm for 30 minutes in a centrifuge (product name: H-9R, manufactured by Kokusan Co., Ltd.). This operation separates the toner particles from the fine particles. After visually confirming that the toner and aqueous solution have been sufficiently separated, the toner that has separated to the top layer is removed, and the aqueous solution is centrifuged to separate and collect the fine particles. The mixture is then dried in a dryer for at least one hour to obtain a sample for measurement. This operation is repeated several times to ensure the required amount.

[0117] In the structures represented by formula (D), formula (T), and formula (Q), Ra, Rb, and Rc bonded to the silicon atom are 13 The measurement conditions are as follows: " 13 C-NMR (solid state) measurement conditions Equipment: JEOL RESONANCE JNM-ECX500II Sample tube: 3.2 mm diameter Sample: 150 mg of fine particles or external additives for toner Measurement temperature: room temperature Pulse mode: CP / MAS Measurement nuclear frequency: 123.25MHz ( 13 C) Reference substance: Adamantane (external standard: 29.5ppm) Sample rotation speed: 20kHz Contact time: 2ms Delay time: 2 seconds Number of times accumulated: 1024

[0118] In the structures represented by formula (D), formula (T), and formula (Q), the presence of Ra, Rb, and Rc can be confirmed by the presence or absence of signals due to the following organic groups: methyl group (Si-CH3), ethyl group (Si-C2H5), propyl group (Si-C3H7), butyl group (Si-C4H9), pentyl group (Si-C5H), and the like, all of which are bonded to silicon atoms. 11 ), hexyl group (Si-CH 13 ), heptyl group (Si-CH 15 ), octyl group (Si-C8H 17 ), alkyl groups such as phenyl group (Si-C6H5-); aryl groups such as phenyl group (Si-C6H5-); alkylene groups such as methine group (>CH-Si), methylene group (Si-CH2-), ethylene group (Si-C2H4-), trimethylene group (Si-C3H6-); and arylene groups such as phenylene group (Si-C6H4-).

[0119] In the structures represented by formula (D), formula (T), and formula (Q), the siloxane bond portion is 29 This was confirmed by Si-NMR (solid state) measurement under the following measurement conditions: " 29 Si-NMR (solid state) measurement conditions Equipment: JEOL RESONANCE JNM-ECX500II Sample tube: 3.2 mm diameter Sample: 150 mg of fine particles or external additives for toner Measurement temperature: room temperature Pulse mode: CP / MAS Measurement nuclear frequency: 97.38MHz ( 29 Si) Reference material: DSS (external standard: 1.534ppm) Sample rotation speed: 10kHz Contact time: 10ms Delay time: 2 seconds Accumulation times: 2000 to 8000 times

[0120] After the above measurement, the peaks of the multiple silane components of the fine particles or toner external additive, which have different substituents and bonding groups, are separated into X1 structure, X2 structure, X3 structure, and X4 structure by curve fitting, and the peak area of ​​each is calculated. X1 structure represented by formula (1): (Rd)(Re)(Rf)SiO 1 / 2 X2 structure represented by formula (2): (Rg)(Rh)Si(O 1 / 2 )2 X3 structure represented by formula (3): RiSi(O 1 / 2 )3 X4 structure represented by formula (4): Si(O 1 / 2 )4 [ka] (Rd, Re, Rf, Rg, Rh, and Ri in formulas (1) to (4) represent an organic group, a halogen atom, a hydroxy group, an acetoxy group, or an alkoxy group bonded to a silicon atom.) In the formulas (1) to (4), the structures enclosed by squares are the X1 structure to the X4 structure, respectively.

[0121] of fine particles or external additives for toner 29 In the chart obtained by Si-NMR measurement, the ratio of the peak area of ​​the X2 to X4 structures attributable to the structures of formulae (D), (T), and (Q) to the total peak area of ​​the organosilicon polymer is preferably 50 mol % or more, and more preferably 70 mol % or more. If you need to confirm the structures represented by formula (D), formula (T), and formula (Q) in more detail, 13 C-NMR and 29 Along with the Si-NMR measurement results 1 The identification may be performed using the results of H-NMR measurement. [Example]

[0122] The present invention will be described in more detail below with reference to specific production examples, examples, and comparative examples, but the present invention is not limited thereto. In the following formulations, "parts" are by mass unless otherwise specified.

[0123] [Production example of approximately hemispherical fine particles 1] <Preparation process of precursor aqueous solution 1> 60.0 parts of ion-exchanged water was weighed into a reaction vessel equipped with a stirrer and a thermometer, and the pH was adjusted to 3.0 using 10% by weight of hydrochloric acid. This was heated with stirring until the temperature reached 60°C. 40.0 parts of methyltrimethoxysilane was then added and stirred for 2 hours. After visually confirming that the oil layer and the aqueous layer had not separated and had become a single layer, the mixture was cooled to obtain aqueous precursor solution 1.

[0124] <Polymerization process> 1000.0 parts of ion-exchanged water were weighed into a reaction vessel equipped with a stirrer and thermometer, and 6.0 parts of Noigen EA177 (manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) and 380.0 parts of PMMA particles (non-crosslinked, number average particle size 10 μm) were added. The mixture was heated with stirring at 180 rpm, the temperature was raised to 50°C and maintained for 30 minutes. While continuing to stir, 34.0 parts of Precursor Aqueous Solution 1 were added. After maintaining this state for 30 minutes, the pH was adjusted to 9.0 using aqueous sodium hydroxide solution. The mixture was maintained for a further 300 minutes, forming roughly hemispherical microparticles made of organosilicon polymer on the surface of the PMMA particles.

[0125] <Cleaning process> After the polymerization process was completed, the reaction solution was cooled and subjected to solid-liquid separation using a pressure filter to obtain a cake of PMMA particles. This was reslurried in ion-exchanged water to form a dispersion again, and then subjected to solid-liquid separation again using a filter. After repeating the reslurrying and solid-liquid separation several times, a final solid-liquid separation was performed to obtain a cake of PMMA particles.

[0126] <Separation and drying process> After the washing step, the PMMA particle cake was added to 1,000 parts of acetone in a reaction vessel equipped with a stirrer and stirred at 180 rpm for 1 hour. After visually confirming that the PMMA particles had dissolved sufficiently, the mixture was centrifuged at 15,000 rpm for 10 minutes, and the precipitate was collected and dried in vacuum. If necessary, the mixture was crushed using a pulverizer (manufactured by Hosokawa Micron Corporation), and the roughly hemispherical particles were separated using an air classifier to obtain roughly hemispherical particles 1. The physical properties of the resulting roughly hemispherical particles 1 are shown in Table 2.

[0127] [Production Examples of Nearly Hemispherical Fine Particles 2 to 20 and Comparative Nearly Hemispherical Fine Particles 1 and 2] According to the formulation and production conditions shown in Table 1, and otherwise in the same manner as in the production example of substantially hemispherical fine particles 1, substantially hemispherical fine particles 2 to 20 and comparative substantially hemispherical fine particles 1 and 2 were obtained. The physical properties of the obtained fine particles are shown in Table 2.

[0128] [Table 1]

[0129] [Table 2] In Table 2, in the "Solid" column, "◯" indicates that the particles are solid, and "×" indicates that the particles are hollow. In the "Nearly Hemispherical" column, "◯" indicates that the particles are nearly hemispherical, and "×" indicates that the particles are not nearly hemispherical.

[0130] [Example of hollow microparticle manufacturing] A reaction vessel was charged with 500 g of ion-exchanged water, and 0.45 g of 48% aqueous sodium hydroxide solution was added to prepare an aqueous solution. 65 g of methyltrimethoxysilane and 50 g of tetraethoxysilane were added to this aqueous solution, and the mixture was stirred for 1 hour while maintaining the temperature at 13-15°C to carry out a hydrolysis reaction. 0.31 g of a 15% aqueous α-(p-nonylphenyl)-ω-hydroxy(polyoxyethylene) solution was then added, and the mixture was stirred at the same temperature for 3 hours to carry out a hydrolysis reaction, yielding a transparent reaction product containing a silanol compound. The resulting reaction product was then stirred for 5 hours while maintaining the pH at 70°C to carry out a condensation reaction, yielding an aqueous suspension containing hollow microparticles composed of an organosilicon compound. This aqueous suspension was filtered through a membrane filter, and the effluent liquid was centrifuged to separate white microparticles. The separated white microparticles were washed with water and then dried with hot air at 150°C for 5 hours to obtain hollow microparticles. The physical properties of the resulting hollow microparticles are shown in Table 2.

[0131] [Example of manufacturing spherical sol-gel silica particles] 500.0 g of methanol, 36.0 g of water, and 41.0 g of 28% by weight aqueous ammonia were added to a glass reactor equipped with a stirrer, dropping funnel, and thermometer and mixed. The temperature of the resulting solution was adjusted to 35°C, and while stirring, the addition of 932.0 g of tetramethoxysilane and 335.0 g of 5.5% by weight aqueous ammonia was simultaneously initiated. Tetramethoxysilane was added dropwise over 6 hours, and the aqueous ammonia was added dropwise over 5 hours. After the dropwise addition of tetramethoxysilane was completed, stirring was continued for an additional 0.5 hours to carry out hydrolysis, yielding a methanol-water dispersion of hydrophilic spherical sol-gel silica microparticles. Next, an ester adapter and a cooling tube were attached to the glass reactor, and the dispersion was thoroughly dried under reduced pressure at 80°C. The resulting silica microparticles were heated in a thermostatic chamber at 400°C for 10 minutes. The obtained silica fine particles were subjected to a crushing treatment using a Pulverizer (manufactured by Hosokawa Micron Corporation). Then, 500 g of silica particles were placed in a 1000 ml polytetrafluoroethylene inner cylinder stainless steel autoclave. After replacing the inside of the autoclave with nitrogen gas, the stirring blade attached to the autoclave was turned on for 6.6 seconds. -1 While rotating at rpm, 0.5 g of HMDS (hexamethyldisilazane) and 0.1 g of water were atomized using a two-fluid nozzle and sprayed uniformly onto the silica powder. After stirring for 30 minutes, the autoclave was sealed and heated at 220°C for 2 hours. Subsequently, the system was depressurized while still heated to perform a deammoniating treatment, yielding spherical sol-gel silica microparticles. The physical properties of the resulting spherical sol-gel silica microparticles are shown in Table 2.

[0132] [Production example of fumed silica fine particles] Commercially available BET30m 2 1 / g of silica particles were passed through an atmosphere heated to 1800°C using a burner at a rate of 0.5 kg / hour, and the silica particles were collected using a collection line and filter using a blower. The particles were then surface-treated with 8 parts by mass of hexamethyldimethalanine, and then separated using an air classifier to obtain fumed silica particles. The physical properties of the resulting particles are shown in Table 2.

[0133] [Production example of toner particle 1] <Aqueous medium preparation process> 14.0 parts of sodium phosphate (Rasa Kogyo Co., Ltd., 12-hydrate) was added to 1000.0 parts of ion-exchanged water in a reaction vessel, and the temperature was maintained at 65 ° C for 1 hour while purging with nitrogen. Using a TK homomixer (Tokushu Kika Kogyo Co., Ltd.), an aqueous calcium chloride solution containing 9.2 parts of calcium chloride (dihydrate) dissolved in 10.0 parts of ion-exchanged water was added all at once while stirring at 12,000 rpm to prepare an aqueous medium containing a dispersion stabilizer. Furthermore, 10% by mass of hydrochloric acid was added to the aqueous medium, and the pH was adjusted to 6.0 to obtain an aqueous medium.

[0134] <Preparation step of polymerizable monomer composition> Styrene: 60.0 parts CI Pigment Blue 15:3: 6.5 parts The above materials were placed in an attritor (manufactured by Mitsui Miike Chemical Engineering Co., Ltd.), and further dispersed using zirconia particles with a diameter of 1.7 mm at 220 rpm for 5 hours to prepare a pigment dispersion. The following materials were added to this pigment dispersion. Styrene: 11.0 parts n-Butyl acrylate: 29.0 parts Crosslinking agent (divinylbenzene): 0.2 parts Saturated polyester resin: 6.0 parts (Condensation polymer of propylene oxide-modified bisphenol A (2-mol adduct) and terephthalic acid (molar ratio 10:12), glass transition temperature Tg = 68°C, weight average molecular weight Mw = 10,000, molecular weight distribution Mw / Mn = 5.12) Fischer-Tropsch wax (melting point 78°C): 10.0 parts Charge control agent: 0.5 parts (Aluminum compound of 3,5-di-tert-butylsalicylic acid) The mixture was kept at 65°C and uniformly dissolved and dispersed at 500 rpm using a TK homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.) to prepare a polymerizable monomer composition.

[0135] <Granulation process> While maintaining the temperature of the aqueous medium at 70°C and the rotation speed of the stirrer at 12,000 rpm, the polymerizable monomer composition was added to the aqueous medium, and 9.0 parts of a polymerization initiator, t-butyl peroxypivalate, was added. Granulation was continued for 10 minutes while maintaining the rotation speed of the stirrer at 12,000 rpm.

[0136] <Polymerization process> The agitator was changed from the high-speed agitator to a propeller agitator blade, and polymerization was carried out for 5 hours while stirring at 150 rpm and maintaining the temperature at 70°C. The temperature was then raised to 95°C and heated for 5 hours to carry out the polymerization reaction, thereby obtaining a toner particle slurry.

[0137] <Cleaning and drying process> After the polymerization process was completed, the toner particle slurry was cooled, and hydrochloric acid was added to the toner particle slurry to adjust the pH of the system to 1.5 or less. After stirring for 1 hour, the toner cake was subjected to solid-liquid separation using a pressure filter. The toner cake was reslurried in ion-exchanged water to form a dispersion again, and then subjected to solid-liquid separation again using a pressure filter. The reslurrying and solid-liquid separation were repeated until the electrical conductivity of the filtrate reached 5.0 μS / cm or less, and finally solid-liquid separation was performed to obtain a toner cake. The obtained toner cake was dried in a flash jet dryer (manufactured by Seishin Enterprises), and further fine and coarse particles were removed using a multi-division classifier utilizing the Coanda effect to obtain toner particles 1. The drying conditions were an inlet temperature of 90°C, a dryer outlet temperature of 40°C, and the toner cake supply rate was adjusted according to the moisture content of the toner cake so that the outlet temperature did not deviate from 40°C. The weight average particle size of the obtained toner particles 1 was 6.2 μm.

[0138] [Production example of toner particles 2] <Preparation process of polyester resin 1> Terephthalic acid: 11.1 moles Bisphenol A-propylene oxide dimer (PO-BPA): 10.9 moles The above monomers were charged into an autoclave together with an esterification catalyst, and the autoclave was equipped with a pressure reducing device, a water separator, a nitrogen gas introducing device, a temperature measuring device, and a stirrer. Under a nitrogen atmosphere and while reducing the pressure, a reaction was carried out according to a conventional method at a temperature of 215°C until the Tg reached 70°C, yielding polyester resin 1. The resulting polyester resin 1 had a weight average molecular weight (Mw) of 7,930 and a number average molecular weight (Mn) of 3,090.

[0139] <Preparation step of polyester resin 2> Bisphenol A ethylene oxide 2 mole adduct 725 parts by mass Phthalic acid 285 parts by mass Dibutyltin oxide 2.5 parts by mass The above materials were stirred at 220°C and reacted for 7 hours, then further reacted under reduced pressure for 5 hours. The mixture was then cooled to 80°C and added to an ethyl acetate solution of 190 parts by weight of isophorone diisocyanate. The mixture was then reacted for 2 hours to obtain an isocyanate group-containing polyester resin. A portion of the resulting reaction solution was used as is to react 25 parts by weight of the isocyanate group-containing polyester resin with 1 part by weight of isophorone diamine at 50°C for 2 hours to obtain polyester resin 2, primarily composed of a urea group-containing polyester. The resulting polyester resin 2 had a weight average molecular weight (Mw) of 22,990, a number average molecular weight (Mn) of 3,020, and a peak molecular weight of 6,810.

[0140] <Toner particle preparation process> In a five-neck pressure vessel equipped with a reflux condenser, a stirrer, a thermometer, and a nitrogen inlet tube, 700 parts by mass of ion-exchanged water, 1,000 parts by mass of a 0.1 mol / L Na3PO4 aqueous solution, and 24.0 parts by mass of a 1.0 mol / L HCl aqueous solution were added, and the mixture was stirred at 12,000 rpm using a high-speed stirring device, TK Homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.), while the temperature was maintained at 63°C. 85 parts by mass of a 1.0 mol / L CaCl2 aqueous solution was gradually added to the mixture, preparing an aqueous dispersion medium containing the fine, poorly water-soluble dispersion stabilizer Ca3(PO4)2. A toner particle precursor composition was then prepared using the following materials: Polyester resin 1 60.0 parts by mass Polyester resin 2 40.0 parts by mass Copper phthalocyanine pigment (Pigment Blue 15:3) 6.5 parts by weight Charge control agent 0.5 parts by mass (Aluminum compound of 3,5-di-tert-butylsalicylic acid) Release agent (behenyl behenate) 10.0 parts by mass The above materials were dissolved in 400 parts by mass of toluene, and the temperature was raised to 63° C. to obtain a toner particle precursor composition. Next, the toner particle precursor composition was added to an aqueous dispersion medium containing a fine, poorly water-soluble dispersion stabilizer, Ca3(PO4)2, and granulated for 5 minutes while stirring at 12,000 rpm with a high-speed stirrer. The high-speed stirrer was then replaced with a propeller stirrer, and the internal temperature was raised to 70°C. The temperature increase took 10 minutes. The mixture was then allowed to react for 5 hours while slowly stirring. The temperature was then raised to 95°C and heated for 5 hours to continue the reaction, yielding a toner particle slurry. After the reaction was completed, washing and drying steps were carried out in the same manner as in the production example of toner particles 1, to obtain toner particles 2. The weight average particle size of the obtained toner particles 2 was 6.2 μm.

[0141] [Production example of toner particle 3] The step of preparing the aqueous medium, the step of preparing the polymerizable monomer composition, and the granulation step were carried out in the same manner as in the production example of toner particles 1.

[0142] <Preparation process of aqueous solution of organosilicon compound> 60.0 parts of ion-exchanged water was weighed into a reaction vessel equipped with a stirrer and a thermometer, and the pH was adjusted to 1.5 using 10% by mass of hydrochloric acid. This was heated with stirring until the temperature reached 80°C. 40.0 parts of methyltriethoxysilane was then added and stirred for 5 minutes to obtain an aqueous solution of an organosilicon compound.

[0143] <Polymerization process> The high-speed agitator was replaced with a propeller agitator, and the polymerization was carried out for 5 hours while stirring at 150 rpm and maintaining the temperature at 70°C. The temperature was then raised to 95°C and heated for 5 hours to produce a toner particle slurry. The slurry was then cooled to 60°C and the pH was measured, which was found to be 5.0. While continuing to stir at 60°C, 30.0 parts of organosilicon compound aqueous solution 1 were added. After maintaining the mixture in this state for 30 minutes, the pH of the slurry was adjusted to 9.0 using aqueous sodium hydroxide and maintained for a further 300 minutes to form an organosilicon polymer on the surface of the toner particles. The washing and drying steps after the polymerization step were carried out in the same manner as in the production example of toner particles 1, to obtain toner particles 3. The weight average particle size of the obtained toner particles 3 was 6.3 μm.

[0144] [Toner 1 manufacturing example] 100.0 parts of toner particles 1 were dry-mixed with 2.0 parts of approximately hemispherical fine particles 1 for 5 minutes in an FM mixer (manufactured by Nippon Coke and Engineering Co., Ltd.), and the externally added particles were then sieved through a mesh with 150 μm openings to obtain toner 1. The physical properties of the obtained toner are shown in Table 3.

[0145] [Production Examples of Toners 2 to 22 and Comparative Toners 1 to 4] Toners 2 to 22 and comparative toners 1 to 4 were obtained in the same manner as in the production example of toner 1, except for the formulation shown in Table 3. The physical properties of the obtained toners are shown in Table 3.

[0146] [Comparative Toner 5] For comparative toner 5, toner particles 3 were used as they were.

[0147] [Table 3]

[0148] [Image output evaluation] <Evaluation of cleaning ability> A tandem type Canon laser beam printer (product name: LBP9600C, hereinafter referred to as "LBP9600C") was modified so that printing was possible using only the cyan station. 120 g of the toner to be evaluated was filled into a toner cartridge for the LBP9600C, and the toner cartridge was left in a low temperature, low humidity L / L (10°C / 15% RH) environment for 24 hours. After leaving the toner cartridge for 24 hours, it was installed in the LBP9600C and the toner loading was 0.25 mg / cm. 2A halftone image of 1.0% was output onto the receiver paper 18. Then, an image with a printing ratio of 1.0% was printed out on 14,000 sheets of A4 paper in landscape orientation. The image output was carried out in a low temperature and low humidity environment (15°C / 10% RH). This condition is more difficult for cleaning because the hardness of the cleaning blade increases, reducing its ability to follow the photosensitive drum 1. After outputting 14,000 sheets, the toner loading amount was 0.25 mg / cm. 2 The halftone image was output onto the image receiving paper 18. The image and the dirt on the charging roller before 14,000 output (initial) and after 14,000 output (after durability evaluation) were evaluated based on the following criteria. The image receiving paper 18 was CS-680 (sold by Canon Marketing Japan Inc., basis weight 68 g / m 2 ) was used. A: No cleaning defects on the halftone image, no stains on the charging roller. B: No cleaning defects on halftone image, dirt on charging roller. C: Very thin vertical lines are observed on the halftone image as a result of poor cleaning. D: 1 to 9 clear vertical lines are observed on the halftone image as a cleaning defect. E: Ten or more clear vertical lines are observed on the halftone image as a result of poor cleaning. In the present invention, a grade of C or higher was judged to be good.

[0149] <Evaluation of low-temperature fixability> The fixing unit of the LBP9600C was modified so that the fixing temperature could be adjusted. Using this modified LBP9600C, the fixing temperature was changed in 5°C increments from 140°C at a process speed of 320 mm / sec. Image output was performed in a low-temperature, low-humidity environment (15°C / 10% RH), which is a difficult condition for low-temperature fixing, as the fixing device is difficult to heat up. The toner to be evaluated was used at a toner loading of 0.40 mg / cm. 2 A solid image was formed on the image receiving paper, and the image was fixed on the image receiving paper by heating and pressing in an oil-free manner. 2The fixed image was rubbed 10 times with a load of 1000 kJ / min., and the temperature at which the image density reduction rate before and after rubbing was less than 10% was taken as the fixing temperature, and evaluation was performed based on the following criteria. The receiving paper is A4 paper (product name: OceRedLabel, manufactured by Canon, weight 80 g / m 2 The image density was measured using a color reflection densitometer X-RITE 404A (manufactured by X-Rite Co.) to measure the relative density of the printout image in the white background area where the original density was 0.00, and the rate of decrease in image density after rubbing was calculated. A: Less than 150℃ B: 150℃ or higher and lower than 156℃ C: 156℃ or higher and lower than 162℃ D: 162℃ or higher and less than 170℃ E: 170℃ or higher In the present invention, a grade of D or higher was judged to be good.

[0150] <Evaluation of component contamination> In the same manner as in the evaluation of cleaning performance, 14,000 images with a printing ratio of 1.0% were printed on A4 paper in landscape orientation in a low temperature and low humidity environment (10°C / 15%RH). After printing 14,000 sheets, the toner loading was 0.25 mg / cm. 2 The halftone image was output onto a receiver paper. The density of the center and the left and right edges (positions 30 mm from the edge of the paper) of the halftone image was measured, and the density difference was calculated and evaluated based on the following criteria. It is known that if the charging member is contaminated, uneven charging occurs on the photosensitive member, resulting in uneven density in halftone images. The receiving paper was CS-680 (sold by Canon Marketing Japan Inc., basis weight 68 g / m 2 The image density was measured using a color reflection densitometer X-RITE 404A (manufactured by X-Rite Co.) to measure the relative density of the printout image in the white background area where the original density was 0.00, and the density difference between the center and edges of the image was calculated. A: The difference in halftone density after durability testing is less than 0.03 B: Halftone density difference after durability test is 0.03 or more and less than 0.05 C: Halftone density difference after durability test is 0.05 or more and less than 0.10 D: Halftone density difference after durability test is 0.10 or more In the present invention, a grade of C or higher was judged to be good.

[0151] [Examples 1 to 22, Comparative Examples 1 to 5] For each toner shown in Table 3, which has each of the fine particles shown in Tables 1 and 2 on the surface of the toner particles, the cleaning ability, low-temperature fixability, and component contamination were evaluated initially and after durability evaluation. The results are shown in Table 4.

[0152] [Table 4]

Claims

1. toner particles containing a binder resin and a colorant; fine particles externally added to the surfaces of the toner particles; A toner having the fine particles contain a condensation polymer of an organosilicon compound, the fine particles are solid and substantially hemispherical, and have substantially flat and curved surfaces; the number average value of the longest diameter w of the approximately flat surface is 10 nm or more and 400 nm or less, When a cross section of the fine particle intersecting with the approximately plane is observed, A line connecting two intersection points Pa and Pb between a line Lf derived from the approximately flat surface and a line Lc derived from the curved surface is defined as a virtual line Li, In a straight line Ls1 perpendicular to the virtual straight line Li, the distance at which either one of the distance Da between an intersection point Pc of the virtual straight line Li and the straight line Ls1 and an intersection point Pe of the line Lc and the straight line Ls1, and the distance Db between an intersection point Pd of the line Lf and the straight line Ls1 and the intersection point Pe is maximum is defined as a maximum height h, When the distance Dc between two intersection points Pf and Pg where the line Ls2 and the line Lc intersect on the line Ls2 parallel to the virtual line Li is the maximum width b, The toner is characterized in that the number average value of the ratio h / b of the maximum height h to the maximum width b is 0.33 or more and 0.80 or less.

2. toner particles containing a binder resin and a colorant; fine particles externally added to the surfaces of the toner particles; A toner having the fine particles contain a condensation polymer of an organosilicon compound, the fine particles are solid and substantially hemispherical, and have substantially flat and curved surfaces; the number average value of the longest diameter w of the approximately flat surface is 10 nm or more and 400 nm or less, The toner, wherein the fine particles contain at least one structure selected from the group consisting of a structure represented by the following formula (D), a structure represented by the following formula (T), and a structure represented by the following formula (Q): (Ra)(Rb)Si(O １／２ ) ２ Formula (D) Rc-Si(O １／２ ) ３ formula (T) Si(O １／２ ) ４ Formula (Q) (In formulas (D), (T), and (Q), Ra, Rb, and Rc represent organic groups bonded to a silicon atom.)

3. The toner according to claim 1 , wherein the substantially flat surface of the fine particles is observed when the surface of the toner particle is observed.

4. 4. The toner according to claim 1, wherein the fine particles are contained in an amount of 0.1 part by mass or more relative to 100 parts by mass of the toner particles.

5. An external toner additive that is solid and substantially hemispherical and has substantially flat and curved surfaces, the number average value of the longest diameter w of the approximately flat surface is 10 nm or more and 400 nm or less, When a cross section of the external toner additive intersecting the approximately flat surface is observed, A line connecting two intersection points Pa and Pb between a line Lf derived from the approximately flat surface and a line Lc derived from the curved surface is defined as a virtual line Li, In a straight line Ls1 perpendicular to the virtual straight line Li, the distance at which either one of the distance Da between an intersection point Pc of the virtual straight line Li and the straight line Ls1 and an intersection point Pe of the line Lc and the straight line Ls1, and the distance Db between an intersection point Pd of the line Lf and the straight line Ls1 and the intersection point Pe is maximum is defined as a maximum height h, When the distance Dc between two intersection points Pf and Pg where the line Ls2 and the line Lc intersect on the line Ls2 parallel to the virtual line Li is the maximum width b, The external toner additive, wherein the number average value of the ratio h / b of the maximum height h to the maximum width b is 0.33 or more and 0.80 or less.

6. 6. The external toner additive according to claim 5, wherein the external toner additive comprises at least one selected from the group consisting of a structure represented by the following formula (D), a structure represented by the following formula (T), and a structure represented by the following formula (Q): (Ra)(Rb)Si(O １／２ ) ２ Formula (D) Rc-Si(O １／２ ) ３ formula (T) Si(O １／２ ) ４ Formula (Q) (In formulas (D), (T), and (Q), Ra, Rb, and Rc represent organic groups bonded to a silicon atom.)

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