toner

Abstract

To provide a toner that maintains good electrostatic stability and transferability, and provides stable image quality, even when used for a long period of time in a high-temperature, high-humidity environment with a low print density. [Solution] A toner having an external additive on the surface of toner particles, wherein the external additive comprises a metal titanate compound fine particle A, a silica fine particle B, and an inorganic fine particle C, and fragment ions corresponding to the dimethylsiloxane structure are observed in the metal titanate compound fine particle A, and furthermore, there are peaks D attributed to the D unit structure, X2 attributed to the X2 unit structure, and X3 attributed to the X3 unit structure, with the area S of peak D. D , area S of peak X2 X2 , area S of peak X3 X3 The given equation is satisfied, and peak 1, representing silica nanoparticles B, is observed in the region of minimum Ferret diameter 5 to 100 nm, while peak 2, representing inorganic nanoparticles C, is observed on the larger particle size side of peak 1 and in the region of minimum Ferret diameter 50 to 1000 nm.

Description

[Technical Field]

[0001] This disclosure relates to toner used in photocopiers and printers that use electrophotographic or electrostatic recording methods. [Background technology]

[0002] In recent years, there has been progress in increasing the speed, extending the lifespan, and improving the environmental stability of photocopiers and printers. Toner cartridges are now required to have stress resistance to withstand friction within the cartridge during long-term high-speed printing, as well as stable electrostatic properties regardless of the operating environment.

[0003] Conventionally, it has been known that adding hydrophobized metal titanate compound fine particles and large-particle inorganic fine particles to toner as external additives stabilizes the charge, imparts good transferability, and allows for the acquisition of high-quality images.

[0004] Patent Document 1 discloses strontium titanate-based fine particles treated with silicone oil or alkoxysilane as an external additive for toner. The above-disclosure strontium titanate-based fine particles are disclosed to be a toner charge control agent with excellent dispersibility, environmental properties, and charge properties.

[0005] Patent Document 2 discloses a two-component developer containing strontium titanate particles surface-treated with a hydrophobic treatment agent, which makes it difficult for pinholes to occur in the photoreceptor and provides excellent image density stability and resistance to fogging.

[0006] Patent Document 3 discloses that a two-component developer containing metal-doped strontium titanate particles having a surface hydrophobized with a silicon-containing organic compound can be used to suppress fogging that occurs in images immediately after the startup of an image forming apparatus. [Prior art documents] [Patent Documents]

[0007] [Patent Document 1] Japanese Patent Publication No. 2015-137208 [Patent Document 2] Japanese Patent Publication No. 2020-129029 [Patent Document 3] Japanese Patent Publication No. 2023-026551 [Overview of the Initiative] [Problems that the invention aims to solve]

[0008] However, even with the above-mentioned measures, there is still room for improvement in the long-term use of high-speed and long-lasting photocopiers and printers in high-temperature and high-humidity environments.

[0009] Metal titanate compound microparticles surface-treated with silane coupling agents alone or silicone oil alone (hereinafter referred to as conventional metal titanate compound microparticles) are prone to surface treatment degradation when used for long-term image output. Metal titanate compound microparticles with degraded surface treatment have a weak electrostatic repulsion force with negatively charged inorganic microparticles. Therefore, with long-term use in high-temperature and high-humidity environments in copiers and printers, the metal titanate compound microparticles with degraded surface treatment and the inorganic microparticles form aggregated particles via moisture, which easily detach from the toner particles. In particular, when images are output for a long period at a low print density, the toner remains in the developer unit for a longer period, making it easy for aggregated particles of metal titanate compound microparticles and inorganic microparticles to accumulate in the developer unit. These accumulated aggregated particles can scrape off components such as the developer carrier and photoreceptor, resulting in image defects (streaks in the paper transport direction). Furthermore, when the above-mentioned aggregated particles are formed, they accumulate in the development control section, causing control failures and resulting in image defects (density unevenness in halftone and solid images).

[0010] This disclosure solves the above problems and provides a toner that can maintain good charge stability and transferability, and obtain stable image quality, even when used for a long period of time in a high temperature and high humidity environment with a low print rate. [Means for solving the problem]

[0011] This disclosure relates to toner particles containing a binder resin and a release agent, and toner having an external additive on the surface of the toner particles, The external additive contains metal titanate compound fine particles A, silica fine particles B, and inorganic fine particles C. In a time-of-flight secondary ion mass spectrometry measurement using the titanate metal compound fine particles A as a sample, fragment ions corresponding to the structure represented by the following formula (1) were observed. Solid using the titanate metal compound fine particles A as a sample 29 Obtained by Si-NMR CP / MAS method 29 In the Si-NMR spectrum, (i) In the range of -25 ppm to -15 ppm, there is a peak D that is attributed to the D unit structure. (ii) In the range of -60 ppm to -50 ppm, there exists a peak X2 that belongs to the X2 unit structure represented by the following formula (2): (iii) In the range of -70 ppm to -60 ppm, there is a peak X3 that belongs to the X3 unit structure represented by the following formula (3), (iv) The area of ​​the peak D is S D The area of ​​the peak X2 is S X2 The area of ​​the peak X3 is S X3 When S D / (S X2 +S X3 ) is between 0.10 and 1.50, The inorganic fine particles C are fine particles selected from the group consisting of silica fine particles C, alumina fine particles C, and titania fine particles C. Based on the particle size distribution of silica microparticles obtained by combining SEM image analysis and EDX analysis of the toner surface, a graph with the minimum Ferret diameter of primary particles on the horizontal axis and frequency on the vertical axis shows a peak value in the region of minimum Ferret diameter 5 to 100 nm, and peak 1 is observed where the main constituent particles are silica microparticles B. Regarding a toner, in a graph having the minimum Feret diameter of primary particles on the horizontal axis and frequency on the vertical axis, based on the particle size distribution of the external additive obtained by combining SEM image analysis and EDX analysis of the surface of the toner, a peak 2 is observed which shows a peak value on the larger particle size side than the peak value of the peak 1 and in the region of a minimum Feret diameter of 50 to 1000 nm, and the main particles constituting it are the inorganic fine particles C.

[0012]

Chemical formula

[0013] (In formula (1), n represents an integer of 2 or more.)

[0014]

Chemical formula

[0015] (In formula (2), R1 represents a hydrocarbon group having 1 to 10 carbon atoms, R2 represents a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, and O 1 / 2 represents an oxygen atom shared with an adjacent Si atom or Ti atom.)

[0016]

Chemical formula

[0017] (In formula (3), R1 represents a hydrocarbon group having 1 to 10 carbon atoms, and O 1 / 2 represents an oxygen atom shared with an adjacent Si atom or Ti atom.)

Advantages of the Invention

[0018] According to the present disclosure, it is possible to provide a toner that can maintain charge stability and good transferability and achieve stable image quality even under high temperature and high humidity environments with low printing rates and long-term use.

Modes for Carrying Out the Invention

[0019] In this disclosure, descriptions of numerical ranges such as "greater than or equal to XX and less than or equal to XX" or "XX to XX" mean a numerical range that includes the lower and upper limits, which are the endpoints, unless otherwise specified. When numerical ranges are described in steps, the upper and lower limits of each numerical range can be combined in any way. In this disclosure, when the titanate metal compound fine particles A are surface-treated with a surface treatment agent, the titanate metal compound fine particles A include the structure derived from the surface treatment agent. The titanate metal compound fine particles A before surface treatment are called the titanate metal compound fine particle substrate.

[0020] First, the inventors focused on the surface of the titanate metal compound nanoparticles. On the surface of the titanate metal compound nanoparticles, some of the oxygen atoms bonded to the titanium atoms exist as hydroxyl groups. Therefore, the surface of the titanate metal compound nanoparticles is easily adsorbed with moisture from the air. In particular, under high temperature and high humidity conditions, the amount of moisture adsorbed on the surface of the titanate metal compound nanoparticles increases, which tends to reduce the electrostatic charge of the titanate metal compound nanoparticles. One method to suppress this reduction in electrostatic charge is to hydrophobize the surface of the titanate metal compound nanoparticles using a silane coupling agent or silicone oil. However, conventional hydrophobization methods have not been able to fully control the amount of hydroxyl groups on the surface of the titanate metal compound nanoparticles, resulting in insufficient electrostatic stability under high temperature and high humidity conditions.

[0021] When metal titanate compound nanoparticles are surface-treated with silane coupling agents alone, silanol groups derived from the silane coupling agent remain on the surface of the metal titanate compound nanoparticles, making it difficult to control the amount of hydroxyl groups on the surface. Therefore, it is difficult to maintain the hydrophobic state and control the charged state of metal titanate compound nanoparticles surface-treated with silane coupling agents alone over the long term. This tendency is also observed when two or more silane coupling agents with different alkyl group structures are used in combination.

[0022] When the surface of metal titanate compound nanoparticles is hydrophobized using only silicone oil, the hydroxyl groups present on the surface of the metal titanate compound nanoparticles are hardly chemically bonded to the silicone oil, making the silicone oil prone to peeling. Therefore, when outputting images at low print density over a long period, the substrate surface of the metal titanate compound nanoparticles becomes exposed, making it difficult to maintain the hydrophobic state and control the charge state of the metal titanate compound surface.

[0023] Increasing the amount of silane coupling agent or silicone oil applied to the metal titanate compound fine particles can reduce the hydroxyl groups present on the surface of the fine particles. However, increasing the amount of silane coupling agent or silicone oil applied to the metal titanate compound fine particles increases their powder resistivity, preventing the desired charging properties from being achieved. Furthermore, it reduces the fluidity of the toner, leading to image defects due to toner aggregation.

[0024] Conventional use of metal titanate compound microparticles and large-particle inorganic particles as external additives to toner improves the toner's charge stability and transferability because the large-particle inorganic particles act as spacer particles. However, when used for extended periods in high-temperature and high-humidity environments, the surface treatment of the metal titanate compound microparticles deteriorates, causing the metal titanate compound microparticles and large-particle inorganic particles to form aggregated particles that detach from the toner. This significantly reduces the toner's charge stability and transferability.

[0025] By adding silica nanoparticles with a large specific surface area and high negative charge to conventional metal titanate compound nanoparticles and large-diameter inorganic particles, the charge stability of the toner is further improved. However, when used for a long period in a high-temperature, high-humidity environment, aggregated particles of metal titanate compound nanoparticles and large-diameter inorganic particles are formed, as described above. Furthermore, electrostatic forces act between the positively charged metal titanate compound nanoparticles and the negatively charged silica nanoparticles, forming stronger and coarser aggregated particles.

[0026] Furthermore, when printing images at a low print density over a long period, the toner remains in the developer unit for a longer time, making it easier for the aforementioned aggregated particles to accumulate in the unit. These accumulated aggregated particles can scrape off components such as the developer carrier and photoreceptor, resulting in image defects (streaks in the paper transport direction). Also, when the aforementioned aggregated particles are formed, they can accumulate in the development control section, causing control failures and resulting in image defects (density unevenness in halftone and solid images).

[0027] As a result of diligent research by the inventors, we have found that by configuring the toner as follows, it is possible to maintain static stability and good transferability, and achieve stable image quality even under high temperature and high humidity conditions, low print yield, and long-term use.

[0028] The toner in this disclosure is Toner particles containing a binder resin and a release agent, and toner having an external additive on the surface of the toner particles, The external additive contains metal titanate compound fine particles A, silica fine particles B, and inorganic fine particles C. In a time-of-flight secondary ion mass spectrometry measurement using the titanate metal compound fine particles A as a sample, fragment ions corresponding to the structure represented by the following formula (1) were observed. Solid using the titanate metal compound fine particles A as a sample 29 Obtained by Si-NMR CP / MAS method 29 In the Si-NMR spectrum, (i) In the range of -25 ppm to -15 ppm, there is a peak D that is attributed to the D unit structure. (ii) In the range of -60 ppm to -50 ppm, there exists a peak X2 that belongs to the X2 unit structure represented by the following formula (2): (iii) In the range of -70 ppm to -60 ppm, there is a peak X3 that belongs to the X3 unit structure represented by the following formula (3), (iv) The area of ​​the peak D is S D The area of ​​the peak X2 is S X2 The area of ​​the peak X3 is S X3 When SD / (S X2 +S X3 ) is between 0.10 and 1.50, The inorganic fine particles C are fine particles selected from the group consisting of silica fine particles C, alumina fine particles C, and titania fine particles C. Based on the particle size distribution of silica microparticles obtained by combining SEM image analysis and EDX analysis of the toner surface, a graph with the minimum Ferret diameter of primary particles on the horizontal axis and frequency on the vertical axis shows a peak value in the region of minimum Ferret diameter 5 to 100 nm, and peak 1 is observed where the main constituent particles are silica microparticles B. The present invention relates to a toner characterized in that, in a graph based on the particle size distribution of the external additive obtained by combining SEM image analysis and EDX analysis of the surface of the toner, with the minimum Ferret diameter of primary particles on the horizontal axis and frequency on the vertical axis, a peak 2 is observed that is on the larger particle size side than the peak value of Peak 1 and in the region of minimum Ferret diameter of 50 to 1000 nm, and the main particles constituting it are the inorganic fine particles C.

[0029] [ka]

[0030] (In equation (1), n ​​represents an integer greater than or equal to 2.)

[0031] [ka]

[0032] (In formula (2), R1 represents a hydrocarbon group having 1 to 10 carbon atoms, R2 represents a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, O 1 / 2 (This represents an oxygen atom shared with an adjacent Si or Ti atom.)

[0033] [ka]

[0034] (In formula (3), R1 represents a hydrocarbon group having 1 to 10 carbon atoms, O 1 / 2 (This represents an oxygen atom shared with an adjacent Si or Ti atom.)

[0035] The requirements of this disclosure are described in detail below.

[0036] The toner of this disclosure contains metal titanate compound fine particles A as an external additive.

[0037] In time-of-flight secondary ion mass spectrometry (TOF-SIMS) measurements using titanate metal compound nanoparticles A as a sample, it is necessary to observe fragment ions corresponding to the structure represented by equation (1). TOF-SIMS is a method for analyzing the composition of a sample surface by irradiating the sample with ions and analyzing the mass of secondary ions emitted from the sample. Since secondary ions are emitted from a region several nanometers deep from the sample surface, it is possible to analyze the structure near the surface of titanate metal compound nanoparticles A. When titanate metal compound nanoparticles A are analyzed by TOF-SIMS, the observation of fragment ions represented by equation (1) indicates that the surface of titanate metal compound nanoparticles A has a polydimethylsiloxane structure.

[0038] [ka]

[0039] (In equation (1), n ​​represents an integer greater than or equal to 2.)

[0040] Furthermore, a solid sample using metal titanate compound fine particles A 29 Obtained by Si-NMR CP / MAS method 29 The following conditions (i) to (iv) must be met in the Si-NMR spectrum. (i) In the range of -25 ppm to -15 ppm, there is a peak D that is attributed to the D unit structure. (ii) In the range of -60 ppm to -50 ppm, there exists a peak X2 that belongs to the X2 unit structure represented by the following formula (2): (iii) In the range of -70 ppm to -60 ppm, there is a peak X3 that belongs to the X3 unit structure represented by the following formula (3), (iv) The area of ​​the peak D is S D The area of ​​the peak X2 is S X2 The area of ​​the peak X3 is S X3 When S D / (S X2 +S X3 The value is between 0.10 and 1.50.

[0041] [ka]

[0042] (In formula (2), R1 represents a hydrocarbon group having 1 to 10 carbon atoms, R2 represents a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, O 1 / 2 (This represents an oxygen atom shared with an adjacent Si or Ti atom.)

[0043] [ka]

[0044] (In formula (3), R1 represents a hydrocarbon group having 1 to 10 carbon atoms, O 1 / 2 (This represents an oxygen atom shared with an adjacent Si or Ti atom.)

[0045] solid 29 In the Si-NMR CP / MAS method, signals originating from low-mobility Si atoms (immobilized Si atoms) in the sample are observed. Therefore, when the titanate metal compound nanoparticles A are solid... 29 When measured using the Si-NMR CP / MAS method, a signal originating from Si atoms immobilized near the surface of the titanate metal compound nanoparticle A is observed. Therefore, solid 29 Obtained by Si-NMR CP / MAS method 29 By analyzing the Si-NMR spectrum, quantitative information about the chemical bonding state of Si atoms near the surface of the titanate metal compound nanoparticle A can be obtained.

[0046] Generally, solid 29 In Si-NMR, four types of peaks can be observed for Si atoms in a solid sample, each assigned to M units (Equation (4)), D units (Equation (5)), T units (Equation (6)), and Q units (Equation (7)). M unit: (R i )(R j )(R k )SiO 1 / 2 Formula (4) D unit: (R g )(R h )Si(O 1 / 2 )2 formula (5) T unit: R m si(O 1 / 2 )3 formula (6) Q unit: Si(O) 1 / 2 )4 formula (7)

[0047] In the above equations (4) to (7), R i , R j , R k , R g , R h , R m This refers to hydrocarbon groups with one or more carbon atoms, halogen atoms, etc., that are bonded to silicon.

[0048] If a solid sample has a D unit structure represented by formula (5), then the solid 29 In the NMR spectrum obtained by Si-NMR, a peak (peak D) attributed to the D unit structure is observed in the range of -25 ppm to -15 ppm. When a solid sample contains a T unit structure represented by formula (6), the solid 29 In the NMR spectrum obtained by Si-NMR, a peak T, attributed to the T unit structure, is observed in the range of -70 ppm to -50 ppm.

[0049] The chemical shift value of peak T, which is attributed to the T unit structure described above, shifts depending on the bonding state of the three oxygen atoms bonded to the Si atom in equation (6). In the case of the structure represented by equation (2) above (hereinafter referred to as the X2 unit structure), where two of the three oxygen atoms bonded to the Si atom in equation (6) are bonded to other Si atoms or Ti atoms, a peak (peak X2) is observed in the range of -60 ppm to -50 ppm. The chemical shift value of peak X2 is observed at -55 ± 3 ppm. In the case of the structure represented by equation (3) (hereinafter referred to as the X3 unit structure), where three of the three oxygen atoms bonded to the Si atom in equation (6) are bonded to other Si atoms or Ti atoms, a peak (peak X3) is observed in the range of -70 ppm to -60 ppm. The chemical shift value of peak X3 is observed at around -65 ± 3 ppm.

[0050] Solid sample containing metal titanate compound fine particles A 29 Obtained by Si-NMR CP / MAS method 29 The presence of peak D in the Si-NMR spectrum indicates that the surface of the titanate metal compound nanoparticle A has a D unit structure. Solid-state sample using titanate metal compound nanoparticle A. 29 Obtained by Si-NMR CP / MAS method 29 The presence of peaks X2 and X3 in the Si-NMR spectrum indicates that the surface of the titanate metal compound nanoparticle A has X2 and X3 unit structures.

[0051] Solid sample containing metal titanate compound fine particles A 29 Obtained by Si-NMR CP / MAS method 29 In the Si-NMR spectrum, the area of ​​peak D is S D The area of ​​the above peak X2 is S X2 The area of ​​the above peak X3 is S X3 When S D / (S X2 +S X3 ) is between 0.10 and 1.50. DThis refers to the amount of Si atoms constituting the D unit structure on the surface of the titanate metal compound nanoparticle A. X2 This represents the amount of Si atoms constituting the X2 unit structure on the surface of the titanate metal compound nanoparticle A. X3 This refers to the amount of Si atoms constituting the X3 unit structure on the surface of the titanate metal compound nanoparticle A.

[0052] By satisfying the above requirements, the surface treatment of the metal titanate compound fine particles A is less likely to deteriorate even when used for a long period of time in a high-temperature, high-humidity environment, and its charge stability can be maintained. Furthermore, the formation of aggregated particles with silica fine particles B and inorganic fine particles C, which will be described later, can be suppressed. The inventors speculate that the effects of this disclosure are obtained by satisfying the above requirements as follows.

[0053] Solid samples consisting of metal titanate compound nanoparticles surface-treated with only a silane coupling agent. 29 Obtained by Si-NMR CP / MAS method 29 In the Si-NMR spectrum, peaks attributed to the X2 unit structure are predominantly observed. From this result, it is inferred that the silane coupling agent present on the surface of the metal titanate compound nanoparticles is in the following state: Of the three alkoxy groups in the silane coupling agent, two react with the hydroxyl groups on the surface of the metal titanate compound, and a chemical bond is formed between the Si atom in the silane coupling agent and the Ti atom on the surface of the metal titanate compound via an oxygen atom. Of the three alkoxy groups in the silane coupling agent, the remaining alkoxy group is either unreacted or has been converted into a silanol group.

[0054] Solid samples consisting of metal titanate compound nanoparticles surface-treated with silicone oil alone. 29 Obtained by Si-NMR CP / MAS method 29In the Si-NMR spectrum, peaks attributed to the D unit structure derived from the dimethylsiloxane structure are predominantly observed. However, the intensity of the peaks attributed to the D unit structure is low. Therefore, it is inferred that the Si atoms in the silicone oil present on the surface of the metal titanate compound nanoparticles are hardly chemically bonded to the Ti atoms on the surface of the metal titanate compound nanoparticles.

[0055] As described above, the surface of the titanate metal compound nanoparticle A contains dimethylsiloxane structures, D unit structures, X2 unit structures, and X3 unit structures. The D unit structure also includes the dimethylsiloxane structure. Since the above effect was obtained when used for a long period of time in a high temperature and high humidity environment, it is thought that the Si atoms contained in the dimethylsiloxane structures, D unit structures, X2 unit structures, and X3 unit structures on the surface of the titanate metal compound nanoparticle A are chemically bonded with Ti atoms, oxygen atoms, etc., present on the surface of the titanate metal compound. D / (S X2 +S X3 By controlling the coefficient of the coefficient of the fine particles to a predetermined range, a strong surface layer can be formed on the surface of the metal titanate compound fine particles A, thereby maintaining charge stability. Furthermore, the formation of aggregated particles with silica fine particles B and inorganic fine particles C, which will be described later, can be suppressed.

[0056] The toner of this disclosure further contains silica fine particles B and inorganic fine particles C as external additives.

[0057] Based on the particle size distribution of silica microparticles obtained by combining SEM image analysis and EDX analysis of the toner surface, it is necessary to observe a peak value in the region of 5-100 nm in the minimum Ferret diameter of primary particles and a peak 1 in the graph where the frequency is on the vertical axis, where the main constituent particles are silica microparticles B.

[0058] By combining SEM image analysis and EDX analysis of the toner surface, the particle size distribution of silica microparticles obtained shows that the above-mentioned Peak 1 can be observed, thereby improving the charge stability of the toner. When the peak value of Peak 1 is 5 nm or greater, silica microparticles B are less likely to become embedded in the toner particles, especially during long-term use in high-temperature and high-humidity environments, and the chargeability and fluidity of the toner are maintained. In addition, since silica microparticles B are easily broken down to primary particles, they can sufficiently cover the surface of the toner particles. When the peak value of Peak 1 is 100 nm or less, silica microparticles B can sufficiently cover the surface of the toner particles, and low-temperature fixing can be maintained even in high-speed machines specialized for low-temperature fixing. It is more preferable that the peak value of Peak 1 is between 10 nm and 50 nm. The peak value of Peak 1 is the minimum Ferret diameter when the frequency in the above-mentioned particle size distribution of silica particles is maximum. Details on the measurement method of the minimum Ferret diameter of silica microparticles and the method for identifying Peak 1 will be described later.

[0059] Furthermore, in a graph based on the particle size distribution of the external additive obtained by combining SEM image analysis and EDX analysis of the toner surface, with the minimum Ferret diameter of primary particles on the horizontal axis and frequency on the vertical axis, it is necessary to observe peak 2, which is located on the larger particle size side than the peak value of peak 1 and in the region of minimum Ferret diameter of 50 to 1000 nm, and whose main constituent particles are inorganic fine particles C.

[0060] The observation of peak 2 in the particle size distribution of the external additive, obtained by combining SEM image analysis and EDX analysis of the toner surface, indicates that inorganic fine particles C have a larger particle size than silica fine particles B. The relationship between peak 1 and peak 2 satisfies the above-mentioned relationship, allowing inorganic fine particles C to act as spacer particles, thereby imparting charge stability and good transferability to the toner. The peak value of peak 2 represents the minimum Ferret diameter at which the frequency of the external additive's particle size distribution is maximized. Details regarding the measurement method for the minimum Ferret diameter of the external additive and the method for identifying peak 2 will be described later.

[0061] When the peak value of Peak 2 is 50 nm or higher, the inorganic fine particles C act as spacer particles, providing good fluidity to the toner. Furthermore, the inorganic fine particles C act as polishing particles, polishing toner deposits fused to the developer carrier or photoreceptor, thereby suppressing image defects caused by toner deposits over the long term. When the peak value of Peak 2 is 1000 nm or lower, the adhesion of the inorganic fine particles C to the toner particles is maintained, preserving the fluidity and transferability of the toner. The range of the peak value of Peak 2 is preferably 70 nm to 300 nm.

[0062] Inorganic fine particles C are fine particles selected from the group consisting of silica fine particles C, alumina fine particles C, and titania fine particles C. Because silica fine particles C, alumina fine particles C, and titania fine particles C have appropriate hardness, they can polish toner fused to the developer carrier or photoreceptor, thereby suppressing image defects caused by toner fused tones.

[0063] Based on the above, when toner contains metal titanate compound fine particles A, silica fine particles B, and inorganic fine particles C as external additives, the charge stability of the toner can be maintained even when used for a long period of time in a high-temperature, high-humidity environment. Furthermore, the formation of aggregated particles caused by metal titanate compound fine particles can be suppressed, thereby suppressing development restriction problems and resulting image defects caused by aggregated particles.

[0064] Based on the particle size distribution of metal titanate compound fine particles obtained by combining SEM image analysis and EDX analysis of the toner surface, a graph with the minimum Ferret diameter of primary particles on the horizontal axis and frequency on the vertical axis was observed, showing a peak value in the region of minimum Ferret diameter 0.5 to 1000 nm, with peak 3 being the main constituent particle of metal titanate compound A, and the peak value of peak 3 was set to D A When (nm), D A It is preferable that the value is 5 to 50 nm. A Having a wavelength of 5-50nm enhances the ability to adjust the amount of charge in the toner. A The more preferable value is 15 to 40 nm. Ais the minimum Feret diameter when the frequency in the particle size distribution of the above metal titanate compound fine particles is at its maximum.

[0065] Also, when the peak value of the above peak 1 is D B (nm) and the peak value of the above peak 2 is D C (nm), it is preferable that D A , D B , D C satisfy the following relational expressions. 0.10 ≦ D A / D B ≦ 10.00 0.01 ≦ D B / D C ≦ 0.80 0.01 ≦ D A / D C ≦ 1.00

[0066] D A / D B means the ratio of the minimum Feret diameter of the primary particles of the metal titanate compound fine particles A to the minimum Feret diameter of the primary particles of the silica fine particles B. D B / D C means the ratio of the minimum Feret diameter of the primary particles of the silica fine particles B to the minimum Feret diameter of the primary particles of the inorganic fine particles C. D A / D C means the ratio of the minimum Feret diameter of the primary particles of the metal titanate compound fine particles A to the minimum Feret diameter of the primary particles of the inorganic fine particles C. D A , D B , D C When D A / D B satisfies the above relational expressions, during long-term use in a high-temperature and high-humidity environment, charging stability and good transferability can be maintained, and the occurrence of development regulation failures due to aggregated particles and associated image defects can be suppressed. D B / D C is preferably 0.50 or more and 3.50 or less. D A / D C is preferably 0.10 or more and 0.43 or less. Also, D A , D B , D C When DB <D A <D C Satisfying this relationship is preferable because it allows for the maintenance of electrostatic stability and good transferability during long-term use in high-temperature and high-humidity environments, and suppresses the occurrence of development control failures and resulting image defects caused by aggregated particles.

[0067] The coverage area ratio (area %) of metal titanate compound fine particles A relative to toner particles is S A The coating area ratio (area %) of silica fine particles B relative to toner particles is S B The coverage area ratio (area %) of inorganic fine particles C relative to toner particles is S C When S A、 S B S C It is preferable that the following relation satisfies. 0.01≦S A / S B ≤0.30 1.00 ≤ S B / S C ≤80.00 0.30≦S A / S C ≤22.00

[0068] S A、 S B S C When the above relation is satisfied, it is possible to maintain electrostatic stability and good transferability during long-term use in high-temperature and high-humidity environments, and to suppress the occurrence of development control failures and resulting image defects caused by aggregated particles. A / S B It is preferably 0.04 or more and 0.21 or less. B / S C It is preferably 5.00 or more and 50.00 or less. A / S C It is preferably 0.70 or more and 12.60 or less. Also, S A S B S C From the viewpoint of toner durability and fixation, it is preferable that the total area percentage is between 10% and 75%. Details on the method for measuring the coverage area ratio of each fine particle relative to the toner particles will be described later.

[0069] <External additives> The toner of this disclosure contains metal titanate compound fine particles A, silica fine particles B, and inorganic fine particles C as external additives. Other external additives may be added as needed.

[0070] <Titanate metal compound fine particles A> As the titanate metal compound fine particles A in this disclosure, it is preferable to use barium titanate fine particles, strontium titanate fine particles, calcium titanate fine particles, etc. The content of titanate metal compound fine particles A in the toner is preferably 0.1 parts by mass or more and 5.0 parts by mass or less, and more preferably 0.3 parts by mass or more and 4.0 parts by mass or less, per 100 parts by mass of toner particles. By setting the content of titanate metal compound fine particles A within this range, the function of adjusting the charge amount of the toner is enhanced.

[0071] The titanate metal compound fine particles A are more preferably strontium titanate fine particles. The method for producing the strontium titanate fine particles is not particularly limited, but examples include wet methods and sintering methods, with the wet method being more preferable due to its high surface treatment efficiency.

[0072] Strontium titanate nanoparticles may contain dopants. For example, the dopants for strontium titanate nanoparticles are not particularly limited, but lanthanides, silica, aluminum, magnesium, calcium, barium, vanadium, chromium, manganese, iron, cobalt, nickel, copper, zinc, gallium, niobium, molybdenum, ruthenium, palladium, indium, antimony, tantalum, tungsten, rhenium, iridium, platinum, bismuth, yttrium, zirconium, niobium, silver, and tin are preferred. Lanthanides include lanthanum and cerium. Among these, lanthanum and silica are more preferred because they are of a size that easily fits into the crystal structure.

[0073] Strontium titanate nanoparticles can be obtained, for example, by a thermal reaction at atmospheric pressure. In this method, a mineral acid plastid product of a titanium compound hydrolysate is used as the titanium oxide source, and a water-soluble acidic metal compound is used as the strontium metal source. These can be reacted at a temperature of 60°C or higher while adding an alkaline aqueous solution, and then the mixture is treated with acid to produce the nanoparticles.

[0074] (Atmospheric pressure heating reaction method) As the titanium oxide source, a mineral acid-disintegrated product of a titanium compound hydrolysate is used. Preferably, metatitanic acid with an SO3 content of 1.0% by mass or less, preferably 0.5% by mass or less, obtained by the sulfuric acid method, can be used after adjusting the pH to 0.8 to 1.5 with hydrochloric acid and disintegrating it. Metatitanic acid with an SO3 content exceeding 1.0% by mass is undesirable because disintegration does not proceed properly.

[0075] As a metal source other than titanium, metal nitrates, hydrochlorides, etc., can be used. For example, strontium nitrate can be used as a nitrate. For example, strontium chloride can be used as a hydrochloride. Among these, when manufactured using strontium nitrate or hydrochloride, the resulting strontium titanate fine particles adopt a perovskite crystal structure, which is preferable because it further improves the environmental stability of the charged state.

[0076] As the alkaline aqueous solution, a caustic alkali can be used, but a sodium hydroxide aqueous solution is preferred.

[0077] In the above-described manufacturing method, factors that affect the particle size of the resulting strontium titanate fine particles include the mixing ratio of the titanium dioxide source and the strontium source during the reaction, the concentration of the titanium dioxide source at the beginning of the reaction, and the temperature and rate of addition when the alkaline aqueous solution is added. These can be adjusted as appropriate to obtain the desired particle size and particle size distribution. It is preferable to prevent the introduction of carbon dioxide, such as by carrying out the reaction under a nitrogen gas atmosphere, to prevent the formation of carbonates during the reaction process.

[0078] In the above-mentioned manufacturing method, factors that affect the particle size distribution of the resulting strontium titanate fine particles include the pH when the metatitanic acid is gelatinized with hydrochloric acid, the initial concentration of the titanium dioxide source, the rate of addition and reaction time when adding the alkaline aqueous solution, and the stirring conditions. In particular, if the system temperature is rapidly lowered after the addition of the alkaline aqueous solution, such as by immersing it in ice water, the reaction can be forcibly stopped before crystal growth saturates, making it easier to broaden the particle size. Also, making the reaction system non-uniform by lowering the stirring speed or changing the stirring method tends to broaden the particle size distribution.

[0079] The mixing ratio of the titanium oxide source and the strontium source during the reaction is preferably 0.90 to 1.40, and more preferably 1.05 to 1.20, in terms of the molar ratio of MxO / TiO2, where M represents a metal other than titanium and its oxide is represented by MxO (where x is 1 when M is an alkaline earth metal and 2 when M is an alkali metal). When the MO / TiO2 molar ratio is 1 or less, the reaction product tends to consist not only of metal titanate but also of unreacted titanium oxide. Relatively speaking, the metal sources other than titanium have high solubility in water, while the titanium oxide source has low solubility in water. Therefore, when the MxO / TiO2 molar ratio is 1 or less, the reaction product tends to consist not only of metal titanate but also of unreacted titanium oxide. The appropriate concentration of the titanium oxide source at the start of the reaction is 0.05 to 1.30 mol / L, preferably 0.08 to 1.00 mol / L, as TiO2.

[0080] When adding the alkaline aqueous solution, a pressure vessel such as an autoclave is required at temperatures above 100°C, and a practical range of 60°C to 100°C is appropriate. Furthermore, the rate at which the alkaline aqueous solution is added determines the particle size of the strontium titanate nanoparticles obtained; a slower rate yields larger particle sizes, while a faster rate yields smaller particle sizes. An appropriate rate for adding the alkaline aqueous solution is 0.001 to 1.2 equivalents / h, preferably 0.002 to 1.1 equivalents / h, relative to the raw materials, and can be adjusted as appropriate depending on the desired particle size.

[0081] (Acid treatment) In the above manufacturing method, it is preferable to further acid-treat the strontium titanate fine particles obtained by the atmospheric pressure heating reaction. When synthesizing strontium titanate fine particles by performing the atmospheric pressure heating reaction, if the mixing ratio of the titanium oxide source and the strontium source exceeds 1.0 in terms of the molar ratio of MxO / TiO2, the unreacted strontium source remaining after the reaction will react with carbon dioxide in the air to generate impurities such as metal carbonates. Furthermore, if impurities such as metal carbonates remain on the surface, the organic surface treatment agent cannot adequately coat the surface when performing an organic surface treatment to impart hydrophobicity due to the influence of the impurities. Therefore, it is preferable to add an alkaline aqueous solution and then acid-treat to remove the unreacted metal source.

[0082] In the acid treatment, it is preferable to adjust the pH to 2.5 to 7.0, more preferably 4.5 to 6.0, using hydrochloric acid. In addition to hydrochloric acid, nitric acid, acetic acid, etc., can be used in the acid treatment. Using sulfuric acid is undesirable because it generates metal sulfates with low solubility in water.

[0083] The mixing of toner particles and metal titanate compound fine particles A can be performed using known mixers such as the Henschel mixer (manufactured by Mitsui Mining Co., Ltd.), Mechanohybrid (manufactured by Nippon Coke Industries Co., Ltd.), Supermixer (manufactured by Kawata Co., Ltd.), and Nobilta (manufactured by Hosokawa Micron Corporation), and the equipment is not particularly limited. Mixing conditions include, for example, the processing volume, the rotation speed of the stirring shaft, the stirring time, the shape of the stirring blades, and the temperature inside the tank.

[0084] The fine particles A of the titanate metal compound in this disclosure are preferably surface-treated in terms of hydrophobicity and electrostatic properties.

[0085] A silane compound may be used as the surface treatment for the metal titanate compound fine particles A. The silane compound is not particularly limited, but examples include alkoxysilanes such as methoxysilane, ethoxysilane, and propoxysilane; halosilanes such as chlorosilane, bromosilane, and iodosilane; hydrosilanes; alkylsilanes; arylsilanes; vinylsilanes; acrylicsilanes; epoxysilanes; silyl compounds; siloxanes; silylureas; silylacetamides; and silane compounds that simultaneously have different substituents as these silane compounds.

[0086] Specific examples include trimethylsilane, trimethylchlorsilane, trimethylethoxysilane, dimethyldichlorsilane, methyltrichlorsilane, trialkoxyalkylsilane, allyldimethylchlorsilane, α-chloroethyltrichlorsilane, β-chloroethyltrichlorsilane, chlormethyldimethylchlorsilane, dimethyldiethoxysilane, dimethyldimethoxysilane, hexamethyldisiloxane, etc.

[0087] Alkyltrialkoxysilanes are particularly preferred from the viewpoint of hydrophobicity and electrostatic properties. Among these, methyltriethoxysilane, ethyltrimethoxysilane, n-propyltrimethoxysilane, isobutyltrimethoxysilane, n-hexyltrimethoxysilane, and n-octyltriethoxysilane are preferably used. More preferably, the alkyl group has 3 to 6 carbon atoms, and isobutyltrimethoxysilane is even more preferred. Alkyltrialkoxysilanes having an alkyl group with 3 to 6 carbon atoms are preferred because they have good reactivity with the surface of the metal titanate compound fine particle substrate and with the silicone oil described later.

[0088] The treatment method with the silane coupling agent is not particularly limited, but examples include spraying the coupling agent onto the surface of the metal titanate compound microparticle substrate, or mixing the vaporized coupling agent with the metal titanate compound microparticle substrate and then heat-treating it. In this case, water, amines, or other catalysts may be used. Surface modification with the coupling agent is preferably carried out under an inert gas atmosphere such as nitrogen. Alternatively, the coupling agent, the metal titanate compound microparticle substrate, and a solvent may be mixed, and the mixture may be heated or dried. In this case, either the coupling agent or the metal titanate compound microparticle substrate may be dispersed in the solvent first, or all components may be mixed simultaneously.

[0089] When the primary particle size of the metal titanate compound microparticle substrate is 0.02 to 0.3 μm, coating it with a hydrophobic agent in an aqueous system is preferable because it exhibits even better dispersibility. While there are no particular limitations on the method of treatment in an aqueous system, a method of adsorbing a silane coupling agent onto the metal titanate compound microparticle substrate slurry in water is preferred.

[0090] For surface treatment of the titanate metal compound fine particles A, a silicone oil may be used. The silicone oil is not particularly limited, but examples include dimethyl silicone oil, alkyl-modified silicone oil, α-methylstyrene-modified silicone oil, chlorophenyl silicone oil, and fluorine-modified silicone oil. The above silicone oil has a viscosity of 1.0 × 10⁻⁶ at 25°C. -7 m 2 / s or more 0.1m 2 Items with a speed of / s or less are preferred.

[0091] Known techniques can be used for silicone oil treatment. For example, a powder of metal titanate compound fine particles and silicone oil can be mixed using a mixer. Alternatively, silicone oil can be sprayed onto the powder of metal titanate compound fine particles using a sprayer; or silicone oil can be dissolved in a solvent and then mixed. The treatment method is not limited to these.

[0092] When the primary particle size of the metal titanate compound microparticle substrate is 0.02 to 0.3 μm, coating it with a hydrophobic agent in an aqueous system is preferable because it exhibits even better dispersibility. While there are no particular limitations on the method of treatment in an aqueous system, a preferred method involves emulsifying silicone oil in water using an emulsifier and then adsorbing the resulting mixture onto the metal titanate compound microparticle substrate slurry.

[0093] As a surface treatment for the metal titanate compound fine particles A, it is more preferable to treat the surface with a silane coupling agent and a silicone oil, and even more preferable to treat the surface with a silane coupling agent followed by a silicone oil treatment. When a silicone oil is applied after a silane coupling treatment, the alkoxy or silanol groups derived from the silane coupling agent react readily with the silicone oil, making it easier to control the amount of dimethylsiloxane structure, D unit structure, X2 unit structure, X3 unit structure, and hydroxyl groups on the surface of the metal titanate compound fine particles A. In particular, when the silane coupling agent is an alkyltrialkoxysilane having an alkyl group with 3 to 6 carbon atoms, the amount of hydroxyl groups on the surface of the metal titanate compound fine particles A can be further controlled, and the effect of improving electrostatic stability can be further obtained. The inventors speculate that the reason for obtaining the above effect is as follows.

[0094] As described above, when a metal titanate compound nanoparticle substrate is surface-treated with a silane coupling agent, the silane coupling agent present on the surface of the metal titanate compound nanoparticles is presumed to be in the following state: Of the three alkoxy groups contained in the silane coupling agent, two alkoxy groups react with the hydroxyl groups on the surface of the metal titanate compound, and a chemical bond is formed between the Si atom in the silane coupling agent and the Ti atom on the surface of the metal titanate compound via an oxygen atom. Of the three alkoxy groups contained in the silane coupling agent, the remaining alkoxy group is either unreacted or exists as a silanol group.

[0095] When a metal titanate compound microparticle substrate, surface-treated with a silane coupling agent, is further surface-treated with silicone oil, a polyaddition reaction occurs between the dimethylsiloxane structure in the silicone oil and the unreacted alkoxy or silanol groups in the silane coupling agent, forming an X3 unit structure. By controlling the reaction state of the silane coupling agent and silicone oil, the amount of dimethylsiloxane structure, D unit structure, X2 unit structure, X3 unit structure, and hydroxyl groups on the surface of the metal titanate compound microparticle A can be controlled. As a result, a strong surface treatment layer can be formed on the surface of the metal titanate compound microparticle A, maintaining electrostatic stability. Furthermore, because the dimethylsiloxane structure is chemically fixed near the surface of the metal titanate compound microparticle A, slipperiness can be imparted to the metal titanate compound microparticle A. As a result, the formation of aggregated particles with silica microparticles B and inorganic microparticles C can be suppressed, maintaining electrostatic stability and suppressing the occurrence of image defects even during long-term use in high-temperature and high-humidity environments.

[0096] In fine particles A of a metal titanate compound surface-treated with a silane coupling agent and silicone oil, S D This refers to the amount of Si atoms constituting the dimethylsiloxane structure on the surface of the titanate metal compound nanoparticle A. X2 This refers to the amount of Si atoms constituting the X2 unit structure derived from the silane coupling agent on the surface of the titanate metal compound nanoparticle A. X3 This refers to the amount of Si atoms constituting the X3 unit structure derived from the silane coupling agent on the surface of the titanate metal compound nanoparticle A.

[0097] In fine particles A of a metal titanate compound surface-treated with a silane coupling agent and silicone oil, S D / (S X2 +S X3 ) represents the ratio of the amount of Si atoms derived from silicone oil to the amount of Si atoms derived from the silane coupling agent near the surface of the titanate metal compound nanoparticle A. D / (S X2 +S X3When the ratio is between 0.10 and 1.50, a robust surface treatment layer can be formed while a moderate amount of hydroxyl groups remain on the surface of the metal titanate compound fine particles. D / (S X2 +S X3 ) is preferably 0.30 or more and 1.00 or less.

[0098] Also, S X2 and S X3 is, S X2 ≤S X3 It is preferable that the relationship is satisfied. X2 and S X3 When the above relationship is satisfied, it is easier to obtain charge stability. In fine particles A of a metal titanate compound surface-treated with a silane coupling agent and silicone oil, S X2 ≤S X3 Satisfying this relationship indicates that more than half of the T unit structures derived from the silane coupling agent present on the surface of the titanate metal compound nanoparticle A undergo polyaddition reactions with dimethylsiloxane structures derived from silicone oil. X2 and S X3 By satisfying the above relationship, the amount of silanol groups (hydroxyl groups) derived from the silane coupling agent can be reduced, making it easier to obtain greater electrostatic stability.

[0099] In a silane coupling agent used for surface treatment of a metal titanate compound fine particle substrate, the length of the alkyl chain bonded to the Si atom is increased. X2 This can be made lower by shortening the alkyl chain length bonded to the Si atom. X2 This can increase the performance. Furthermore, by surface-treating the titanate metal compound fine particle substrate with a silane coupling agent, and then surface-treating it with a treatment agent such as silicone oil, S X2 It can be lowered.

[0100] <Carbon content in titanium oxide metal compound fine particles A> The amount of silane coupling agent or silicone oil applied to the surface treatment of the titanate metal compound fine particles A can be determined by measuring the carbon atom content (hereinafter referred to as C content) in the titanate metal compound fine particles A. The C content (mass%) in the titanate metal compound particles A is preferably 0.5 to 10.0 mass%.

[0101] When the C content is 10.0% by mass or less, the disintegration properties of the titanate metal compound fine particles A are good, suppressing the formation of aggregated particles with silica fine particles B and inorganic fine particles C, and providing good fluidity to the toner. When the C content is 0.5% by mass or more, a sufficient amount of surface treatment agent is present on the surface of the titanate metal compound fine particles A, suppressing the decrease in electrostatic properties even in high temperature and high humidity environments. Furthermore, by keeping the C content within the above range, the powder resistivity of the titanate metal compound particles A can also be controlled. By using titanate metal compound fine particles A, silica fine particles B, and inorganic fine particles C in combination as external additives, the electrostatic stability of the toner can be improved.

[0102] The amount (parts by mass) of silane coupling agent or silicone oil applied to metal titanate compound fine particles A is preferably 1.0 to 25.0 parts by mass, and more preferably 1.0 to 15.0 parts by mass, per 100 parts by mass of the metal titanate compound fine particle substrate. The silane coupling agent or silicone oil may be used individually, or two or more types may be used in combination.

[0103] <Silica microparticles B> As silica nanoparticles B, any silica nanoparticles obtained by known methods can be used without particular limitation. Examples include sol-gel silica nanoparticles produced by the sol-gel method, aqueous colloidal silica nanoparticles, alcoholic silica nanoparticles, fumed silica nanoparticles obtained by the gas phase method, and fused silica nanoparticles.

[0104] In particular, fumed silica is excellent at imparting fluidity to toner and is suitable as a silica fine particle substrate used as an external additive for electrophotographic toner.

[0105] For silica nanoparticles B, it is preferable to use a silica nanoparticle substrate that has been surface-treated. Surface treatment methods include chemical treatment with a silicon compound that reacts with or physically adsorbs to the silica nanoparticle substrate. The specific surface area of ​​the above-mentioned silica nanoparticle substrate due to nitrogen adsorption, as measured by the BET method, is 30 m². 2 / g or more 300m 2 It is preferable that the value be less than or equal to / g.

[0106] The content of silica fine particles B in the toner is preferably 0.1 parts by mass or more and 10.0 parts by mass or less per 100 parts by mass of toner particles, and more preferably 0.3 parts by mass or more and 4.0 parts by mass or less. By setting the content of silica fine particles B within this range, the function of adjusting the charge amount of the toner is enhanced.

[0107] <Inorganic fine particles C> The inorganic fine particles C are fine particles selected from the group consisting of silica fine particles C, alumina fine particles C, and titania fine particles C. Preferably, the inorganic fine particles C have a Vickers hardness of 5.0 GPa or more and 18.0 GPa or less.

[0108] Examples of silica nanoparticles C include sol-gel silica nanoparticles produced by the sol-gel method, aqueous colloidal silica nanoparticles, alcohol-based silica nanoparticles, fumed silica nanoparticles obtained by the gas-phase method, and fused silica nanoparticles.

[0109] The content of inorganic fine particles C in the toner is preferably 0.05 parts by mass or more and 3.00 parts by mass or less per 100 parts by mass of toner particles, and more preferably 0.10 parts by mass or more and 1.00 parts by mass or less.

[0110] <Other external additives> Other external additives include, specifically, inorganic fine particles such as hydrotalcite particles, and resin fine particles such as vinyl resins, polyester resins, and silicone resins. It is preferable to add these external additives by applying shear force, for example, in a dry state.

[0111] The hydrotalcite particles may be, for example, general hydrotalcite particles represented by the following structural formula (A). M 2+ y M 3+ x (OH)2A n- (x / n)·mH2O ···(A) Here, 0 <x≦0.5、y=1-x、m≧0である。

[0112] Also, M 2+ , and M 3+ These represent divalent and trivalent metal ions, respectively.

[0113] M 2+ It is preferable that is at least one divalent metal ion selected from the group consisting of Mg, Zn, Ca, Ba, Ni, Sr, Cu, and Fe. 3+ It is preferable that the element is at least one trivalent metal ion selected from the group consisting of Al, B, Ga, Fe, Co, and In.

[0114] A n- It is an n-valent anion, CO3 2- , OH - Cl - , I - F - , Br - SO4 2- , HCO3 - CH3COO - , and NO3 - These are examples, and there may be one or more species.

[0115] Hydrotalcite particles, 3+ It is preferable that it contains at least Al. Also, M 2+ It is preferable that it contains at least Mg. It is more preferable that the hydrotalcite particles contain Al and Mg. The hydrotalcite particles may be a solid solution containing multiple different elements. It may also contain trace amounts of monovalent metals.

[0116] <Binding resin> The toner particles contain a binder resin. Preferably, the binder resin content is 50% by mass or more of the total amount of resin components in the toner particles.

[0117] The binder resin is not particularly limited, but examples include styrene-acrylic resin, epoxy resin, polyester resin, polyurethane resin, polyamide resin, cellulose resin, polyether resin, and mixed resins or composite resins thereof. Preferably, the binder resin contains at least one selected from the group consisting of styrene-acrylic resin and polyester resin. More preferably, the binder resin contains styrene-acrylic resin.

[0118] Examples of styrene-acrylic resins include homopolymers composed of the following polymerizable monomers, copolymers obtained by combining two or more of these monomers, and mixtures thereof.

[0119] Styrene monomers such as styrene, 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 (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, iso-propyl (meth)acrylate, n-butyl (meth)acrylate, iso-butyl (meth)acrylate, tert-butyl (meth)acrylate, n-amyl (meth)acrylate, n-hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate (Meth)acrylic monomers such as rilate, n-octyl (meth)acrylate, n-nonyl (meth)acrylate, cyclohexyl (meth)acrylate, benzyl (meth)acrylate, dimethyl phosphate ethyl (meth)acrylate, diethyl phosphate ethyl (meth)acrylate, dibutyl phosphate ethyl (meth)acrylate and 2-benzoyloxyethyl (meth)acrylate, (meth)acrylonitrile, 2-hydroxyethyl (meth)acrylate, (meth)acrylic acid, maleic acid; vinyl ether monomers such as vinyl methyl ether and vinyl isobutyl ether; vinyl ketone monomers such as vinyl methyl ketone, vinyl ethyl ketone, and vinyl isopropenyl ketone; and polyolefins such as ethylene, propylene, and butadiene.

[0120] Styrene acrylic resin can use polyfunctional polymerizable monomers as needed. Examples of polyfunctional polymerizable monomers include diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, 2,2'-bis(4-(meth)acryloxydiethoxy)phenyl)propane, trimethylolpropane tri(meth)acrylate, tetramethylolmethane tetra(meth)acrylate, divinylbenzene, divinylnaphthalene, and divinyl ether.

[0121] Toner particles are preferable to have polyester resin D on their surface for better environmental stability.

[0122] The polyester resin D preferably has at least one monomer unit selected from the group consisting of monomer units corresponding to alcohols having an alicyclic structure and monomer units corresponding to carboxylic acids having an alicyclic structure as monomer units constituting the polymer chain. "Monomer unit" refers to a structure formed by the reaction of monomers in a polymer.

[0123] Polyester resin D is, for example, a polycondensate of an acid component and an alcohol component. A polymer chain is formed by this polycondensation. The polymer chain contains a structure in which monomer units obtained from the acid component and monomer units obtained from the alcohol component are linked by ester bonds. For example, these monomer units form repeating units. It is preferable that at least one of the monomer units obtained from the acid component and the monomer units obtained from the alcohol component of polyester resin D has an alicyclic structure. Furthermore, it is preferable that the alicyclic structure is incorporated into the main chain of the polyester resin.

[0124] The polyester resin D may have only a linear main chain, or it may have a branched chain consisting of a main chain and side chains. In the case of a branched chain, alicyclic structures can be incorporated as constituent units of the main chain and / or side chains.

[0125] The weight-average molecular weight (Mw) of polyester resin D is, for example, 5,000 to 50,000, preferably 8,000 to 20,000.

[0126] Furthermore, alicyclic compounds refer to compounds that contain a cyclic structure that does not possess aromaticity. In classification based on constituent elements, alicyclic structures include alicyclic hydrocarbon structures in which the cyclic structure that does not possess aromaticity consists only of carbon and hydrogen, and alicyclic heterocyclic structures in which the cyclic structure that does not possess aromaticity contains carbon, hydrogen, and other elements. Both of these alicyclic structures can be used.

[0127] Examples of monomers containing alicyclic hydrocarbon structures, such as acid monomers and alcohol monomers, include the following various monomers.

[0128] Examples of acid monomers include 1,4-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid, 4-methyl-1,2-cyclohexanedicarboxylic acid, cis-4-cyclohexene-1,2-dicarboxylic acid, cis-1-cyclohexene-1,2-dicarboxylic acid, norbornanedicarboxylic acid, norbornenedicarboxylic acid, 1,3-adamantanedicarboxylic acid, 1,3,5-cyclohexanetricarboxylic acid, 1,2,4-cyclohexanetricarboxylic acid, 1,2,4,5-cyclohexanetetracarboxylic acid, 1,2,3,4,5,6-cyclohexanehexacarboxylic acid, and methylcyclohexentricarboxylic acid.

[0129] Examples of alcohol monomers include 1,4-cyclohexanediol, hydrogenated bisphenol A, 1,4-cyclohexanediol, 1,2-cyclohexanediol, 1,3-cyclohexanediol, 4-(2-hydroxyethyl)cyclohexanol, 4-(hydroxymethyl)cyclohexanol, 4,4'-bicyclohexanol, and 1,3-adamantanediol. Examples of monomers having an alicyclic heterocyclic structure include isosorbide and spiroglycol as alcohol monomers.

[0130] In particular, it is more preferable that the main chain and / or side chains of the polyester resin have an isosorbide structure as a constituent unit of the polymer chain by using isosorbide as the alcohol monomer. Having an isosorbide structure makes the toner surface highly polar, making it easier to attract hydrotalcite electrostatically to an appropriate degree. As a result, the concentration of hydrotalcite can be suppressed. That is, it is preferable that the polyester resin D has a monomer unit corresponding to isosorbide.

[0131] The monomer unit corresponding to isosorbide is represented by the following formula (H).

[0132] [ka]

[0133] Polyester resin D can be prepared by dehydration condensation of, in addition to alcohols or carboxylic acids having an alicyclic structure, dibasic acids or their derivatives (carboxylic acid halides, esters, acid anhydrides) and dihydric alcohols, and optionally trifunctional or higher polybasic acids, their derivatives (carboxylic acid halides, esters, acid anhydrides), monobasic acids, trifunctional or higher alcohols, monohydric alcohols, etc.

[0134] Examples of dibasic acids include aliphatic dibasic acids such as maleic acid, fumaric acid, itaconic acid, oxalic acid, malonic acid, succinic acid, dodecylsuccinic acid, dodecenylsuccinic acid, adipic acid, azelaic acid, sebacic acid, and decane-1,10-dicarboxylic acid; and aromatic dibasic acids such as phthalic acid, tetrahydrophthalic acid, hexahydrophthalic acid, tetrabromophthalic acid, tetrachlorophthalic acid, hetic acid, hymic acid, isophthalic acid, terephthalic acid, and 2,6-naphthalenedicarboxylic acid. Derivatives of dibasic acids include carboxylic acid halides, esters, and acid anhydrides of the above-mentioned aliphatic dibasic acids and aromatic dibasic acids.

[0135] Examples of divalent alcohols include aliphatic diols such as ethylene glycol, 1,2-propylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, diethylene glycol, dipropylene glycol, triethylene glycol, and neopentyl glycol; bisphenols such as bisphenol A and bisphenol F; bisphenol A alkylene oxide adducts such as ethylene oxide adducts of bisphenol A and propylene oxide adducts of bisphenol A; and aralkylene glycols such as xylylene diglycol.

[0136] Examples of the above-mentioned polybasic acids with three or more functions and their anhydrides include trimellitic acid, trimellitic anhydride, 1,3,5-cyclohexanetricarboxylic acid, 1,2,4-cyclohexanetricarboxylic acid, 1,2,4,5-cyclohexanetetracarboxylic acid, 1,2,3,4,5,6-cyclohexanehexacarboxylic acid, methylcyclohexentricarboxylic acid, methylcyclohexentricarboxylic acid anhydride, pyromellitic acid, pyromellitic anhydride, and the like.

[0137] Polyolefins such as ethylene, propylene, and butadiene.

[0138] <Static control agents and static control resins> Toner particles may contain a charge control agent and / or a charge control resin. Known charge control agents can be used, and charge control agents that have a fast triboelectric charging speed and can stably maintain a constant amount of triboelectric charge are particularly preferred. Furthermore, when toner particles are manufactured by suspension polymerization, charge control agents that have low polymerization inhibitory properties and substantially no solubilizes in aqueous media are particularly preferred.

[0139] Examples of materials that control the toner's charge characteristics include monoazo metal compounds, acetylacetone metal compounds, aromatic oxycarboxylic acids, aromatic dicarboxylic acids, oxycarboxylic and dicarboxylic acid-based metal compounds, aromatic oxycarboxylic acids, aromatic mono and polycarboxylic acids and their metal salts, anhydrides, esters, phenol derivatives such as bisphenol, urea derivatives, metal-containing salicylic acid compounds, metal-containing naphthoic acid compounds, and charge-controlling resins.

[0140] The toner particles preferably have a charge-controlling resin on their surface that has an ionic functional group with a structure represented by the following formula (8). The charge-controlling resin is preferably a vinyl resin, and more preferably a styrene resin.

[0141] [ka]

[0142] In formula (8), R 1 Each of these independently represents an alkyl group having 1 to 18 carbon atoms, or an alkoxy group having 1 to 18 carbon atoms, where n is an integer from 0 to 3, and * is the bonding site with the polymer. 1 Examples of alkyl groups include methyl, ethyl, propyl, isopropyl, butyl, isobutyl, s-butyl, and t-butyl groups, while examples of alkoxy groups include methoxy, ethoxy, and propoxy groups.

[0143] The presence of the above-mentioned charge-controlling resin improves not only the charge rise time and charge stability but also the environmental stability. The content of the charge-controlling resin in the toner particles is preferably 0.1 to 3.0 parts by mass, and more preferably 0.2 to 1.0 parts by mass, per 100 parts by mass of the binder resin.

[0144] Any resin having an ionic functional group can be used, as long as it has an ionic functional group of formula (8). For example, polymers of vinyl salicylic acid and vinyl-1-phthalate are preferred. The electronically controlled resin is preferably a vinyl resin (more preferably a styrene resin) having a structure corresponding to the monomer shown in the following formula (9).

[0145] [ka]

[0146] There are no particular restrictions on the main chain structure of the polymer. Examples include vinyl polymers, polyester polymers, polyamide polymers, polyurethane polymers, and polyether polymers. Hybrid polymers, which are combinations of two or more of these, are also acceptable. Among these, vinyl polymers are preferred when considering adhesion to toner matrix particles.

[0147] Examples of substances that control the positive charge of toner include nigrosine and fatty acid metal salts; quaternary ammonium salts such as tributylbenzylammonium-1-hydroxy-4-naphthosulfonate and tetrabutylammonium tetrafluoroborate, and their analogues; onium salts such as phosphonium salts and their lake pigments; triphenylmethane dyes and their lake pigments (lakers include phosphotungstic acid, phosphomolybdic acid, phosphotungstenmolybdic acid, tannic acid, lauric acid, gallic acid, ferricyanic acid, and ferrocyanic compounds); metal salts of higher fatty acids; and charge-controlling resins.

[0148] The toner particles preferably contain a charge-controlling resin that controls the toner's positive charge. In particular, it is preferable that the toner particles contain a charge-controlling resin containing a quaternary ammonium salt and a quaternary ammonium base. By including the above, the adhesion to the hydrotalcite toner particles becomes appropriate, improving the charge rise time and charge stability.

[0149] <Release agent> The toner particles contain a release agent. Known waxes can be used as the release agent.

[0150] Specifically, these include petroleum-based waxes such as paraffin wax, microcrystalline wax, and petrolactam, and their derivatives; montan wax and its derivatives; hydrocarbon waxes and their derivatives produced by the Fischer-Tropsch process; polyolefin waxes represented by polyethylene and polypropylene, and their derivatives; natural waxes such as carnauba wax and candelilla wax, and their derivatives; and ester waxes. Here, derivatives include oxides, block copolymers with vinyl monomers, and graft-modified products.

[0151] Ester waxes can include monofunctional and difunctional ester waxes, as well as polyfunctional ester waxes such as tetrafunctional and hexafunctional waxes. Examples of aliphatic ester waxes are listed below. The number of functions indicates the number of ester groups contained in one molecule. For example, behenyl behenate is a monofunctional ester wax, while dipentaerythritol hexabehenate is called a hexafunctional ester wax.

[0152] As described above, the toner particles preferably contain ester wax. The ester wax is preferably a polyfunctional ester wax having two or more ester groups, and more preferably a bifunctional ester wax having two ester groups.

[0153] As monofunctional aliphatic ester waxes, condensates of a monocarboxylic acid having 4 to 28 carbon atoms and a monoalcohol having 4 to 28 carbon atoms can be used. For example, at least one selected from the group consisting of stearyl stearate, behenyl stearate, stearyl behenate, and behenyl behenate is preferred, and at least one selected from the group consisting of behenyl behenate and behenyl stearate is more preferred.

[0154] As bifunctional aliphatic ester waxes, condensates of dicarboxylic acids and monoalcohols, or condensates of diols and monocarboxylic acids can be used.

[0155] Examples of dicarboxylic acids include adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, and dodecanediic acid.

[0156] Examples of diols include ethylene glycol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, and 1,12-dodecanediol.

[0157] Aliphatic alcohols are preferred as the monoalcohol to be condensed with the dicarboxylic acid. Specifically, examples include tetradecanol, pentadecanol, hexadecanol, heptadecanol, octadecanol, nonadecanol, eicosanol, docosanol, tricosanol, tetracosanol, pentacosanol, hexacosanol, octacosanol, and the like.

[0158] Examples of monocarboxylic acids that can be condensed with diols include lauric acid, myristic acid, palmitic acid, margaric acid, stearic acid, tubercurostearic acid, arachidic acid, behenic acid, lignoceric acid, and cerotic acid.

[0159] Examples of trifunctional SL waxes include condensates of glycerin compounds and monofunctional aliphatic carboxylic acids.

[0160] Examples of the tetrafunctional ester wax include condensates of pentaerythritol and monofunctional aliphatic carboxylic acids, and condensates of diglycerin and aliphatic carboxylic acids. Examples of the pentafunctional ester wax include condensates of triglycerin and monofunctional aliphatic carboxylic acids. Examples of the hexafunctional ester wax include condensates of dipentaerythritol and monofunctional aliphatic carboxylic acids, and condensates of tetraglycerin and monofunctional aliphatic carboxylic acids.

[0161] Also, the content of the release agent is preferably 1.0 part by mass or more and 30.0 parts by mass or less with respect to 100.0 parts by mass of the binder resin. The content of the ester wax in the toner particles is preferably 1.0 to 10.0 parts by mass, more preferably 2.0 to 8.0 parts by mass, with respect to 100 parts by mass of the binder resin.

[0162] <Colorant> The toner particles may contain a colorant. Known pigments and dyes can be used as the colorant. Pigments are preferred as the colorant in terms of excellent weather resistance.

[0163] Examples of the cyan-based colorant include copper phthalocyanine compounds and their derivatives, anthraquinone compounds, and basic dye lake compounds.

[0164] Specifically, the following can be mentioned. C.I. Pigment Blue 1, 7, 15, 15:1, 15:2, 15:3, 15:4, 60, 62 and 66.

[0165] Examples of the magenta-based colorant include condensed azo compounds, diketopyrrolopyrrole compounds, anthraquinone compounds, quinacridone compounds, basic dye lake compounds, naphthol compounds, benzimidazolone compounds, thioindigo compounds, and perylene compounds.

[0166] Specifically, the following are listed: CI Pigment Red 2, 3, 5, 6, 7, 23, 48:2, 48:3, 48:4, 57:1, 81:1, 122, 144, 146, 150, 166, 169, 177, 184, 185, 202, 206, 220, 221 and 254, and CI Pigment Violet 19.

[0167] Examples of yellow colorants include condensed azo compounds, isoindolinone compounds, anthraquinone compounds, azo metal complexes, methine compounds, and allylamide compounds.

[0168] Specifically, the following are listed: CI Pigment Yellow 12, 13, 14, 15, 17, 62, 74, 83, 93, 94, 95, 97, 109, 110, 111, 120, 127, 128, 129, 147, 151, 154, 155, 168, 174, 175, 176, 180, 181, 185, 191, and 194.

[0169] Examples of black colorants include those formulated to produce black using the above-mentioned yellow, magenta, and cyan colorants, as well as carbon black and magnetic materials.

[0170] These colorants can be used individually, in mixtures, or even in a solid solution. Preferably, the colorant is used in an amount of 1.0 part by mass to 20.0 parts by mass per 100.0 parts by mass of the binder resin. When using a magnetic material and applying the manufacturing method in an aqueous medium described later, a hydrophobic treatment may be performed to ensure stable inclusion of the magnetic material in the resin.

[0171] <Average circularity of toner particles> The average circularity of the toner particles is preferably between 0.960 and 0.995. When the average circularity of the toner particles is within this range, the charge rise time improves. The method for measuring the average circularity of the toner particles will be described later.

[0172] <Method for manufacturing toner particles> The method for producing toner particles is not particularly limited, and known methods such as grinding, suspension polymerization, dissolution-suspension, emulsification-coagulation, and dispersion polymerization can be used. Among these, suspension polymerization is preferred because it allows for high control of the average circularity of the toner particles and exhibits high fluidity and electrostatic properties.

[0173] The weight-average particle size (D4) of the toner particles is preferably 4.0 to 12.0 μm, and more preferably 5.0 to 10.0 μm.

[0174] [Measurement methods for each physical property] Next, we will describe the measurement methods for each physical property.

[0175] <Method for separating toner particles, metal titanate compound fine particles A, silica fine particles B, and inorganic fine particles C from toner> When measuring the physical properties of metal titanate compound fine particles A, silica fine particles B, inorganic fine particles C, and toner particles, they can be separated from the toner and measured using the following procedure.

[0176] Add 1.6 kg of sucrose (manufactured by Kishida Chemical Co., Ltd.) to 1 L of deionized water and dissolve it over a water bath to prepare a concentrated sucrose solution. Place 31 g of this concentrated sucrose solution and 6 mL of Contaminon N (a 10% by mass aqueous solution of a pH 7 neutral detergent for cleaning precision measuring instruments, consisting of a nonionic surfactant, anionic surfactant, and organic builder, manufactured by Wako Pure Chemical Industries, Ltd.) into a centrifuge tube to prepare a dispersion. Add 10 g of toner to this dispersion and break up any clumps of toner with a spatula or similar tool.

[0177] The centrifugation tube is placed in an Iwaki Sangyo Co., Ltd. "KM Shaker" (model: V.SX) and shaken for 20 minutes at a rate of 350 strokes per minute. After shaking, the solution is transferred to a 50 mL glass tube for the swing rotor and centrifuged in a centrifuge at 3500 rpm for 30 minutes.

[0178] After centrifugation, toner particles are present in the uppermost layer of the glass tube, while a mixture of fine particles containing metal titanate compound fine particles A, silica fine particles B, and inorganic fine particles C is present in the lower aqueous solution layer. The upper and lower aqueous solutions are separated and dried, obtaining toner particles from the upper layer and the mixture of fine particles from the lower layer. The centrifugation process is repeated until the total amount of the mixture of fine particles obtained from the lower layer is 10 g or more.

[0179] Next, 10 g of the obtained fine particle mixture is added to a dispersion containing 100 mL of deionized water and 6 mL of the above-mentioned Contaminon N and dispersed. The resulting dispersion is transferred to a 50 mL glass tube for a swing rotor and centrifuged in a centrifuge at 3500 rpm for 30 minutes.

[0180] After centrifugation, silica microparticles B and inorganic microparticles C are present in the uppermost layer of the glass tube, while metal titanate compound microparticles A are present in the lower aqueous solution layer. The lower aqueous solution is collected and dried, and metal titanate compound microparticles A are separated and collected. The upper aqueous solution is also collected, and centrifugation is repeated as needed to ensure sufficient separation. After the dispersion is dried, silica microparticles B and inorganic microparticles C are collected.

[0181] <Method for measuring the content of metal titanate compound fine particles A, silica fine particles B, and inorganic fine particles C> Toner particles, metal titanate compound fine particles A, silica fine particles B, and inorganic fine particles C are separated from the toner using the method described above. The masses of the obtained toner particles, metal titanate compound fine particles A, silica fine particles B, and inorganic fine particles C are measured. From the masses of the obtained toner particles, metal titanate compound fine particles A, silica fine particles B, and inorganic fine particles C, the content of each particle per 100 parts by mass of toner particles is calculated.

[0182] If inorganic nanoparticles C are silica nanoparticles and separation of silica nanoparticles B and inorganic nanoparticles C is difficult, the masses of silica nanoparticles B and inorganic nanoparticles C are calculated using the following method. The minimum Ferret diameter D of silica nanoparticles B obtained by the method described later. B and coverage area ratio SB The product X with B is defined as such, and the Feret minimum diameter D of silica particles C which are inorganic fine particles C C and the coating area ratio S C The product X with C is defined as X. B Using X and C the masses of silica particles B and inorganic fine particles C are calculated by the following formula. (Mass of silica particles B) =(Total mass of silica particles B and inorganic fine particles C) × X B / (X B + X C ) (Mass of inorganic fine particles C) =(Total mass of silica particles B and inorganic fine particles C) × X C / (X B + X C )

[0183] <Method for Calculating Feret Minimum Diameter and Coating Area Ratio of Primary Particles of Metal Titanate Compound Particles A, Silica Particles B, and Inorganic Fine Particles C> The Feret minimum diameter and coating area ratio of the primary particles of metal titanate compound particles A, silica particles B, and inorganic fine particles C are calculated from image analysis by combining secondary electron images and backscattered electron images obtained by SEM observation and elemental mapping images obtained by EDX measurement. Details are shown below.

[0184] (Method for Obtaining Secondary Electron Image and Backscattered Electron Image of Toner Particles) The secondary electron image and backscattered electron image of toner particles are simultaneously obtained in the same field of view using the following device. Device used: ULTRA PLUS manufactured by Carl Zeiss Microscopy Co., Ltd. Accelerating voltage: 0.7 kV WD: 2.5 mm Aperture Size: 30.0 μm Secondary electron image detection signal: SED (secondary electron) Backscattered electron image detection signal: EsB (energy - selected backscattered electron) EsB Grid: 400 V Observation magnification: 100,000 times Contrast: 63.0 ± 5.0% (reference value) Brightness: 38.0 ± 5.0% (reference value) Resolution: 1024 x 768 pixels Pre-treatment: Toner is sprayed onto carbon tape (Pt deposition is not performed).

[0185] Contrast and brightness should be set appropriately according to the condition of the equipment being used. The acceleration voltage and EsB grid should be set to achieve objectives such as acquiring structural information of the outermost surface of toner particles, preventing charge-up of undeposited samples, and selective detection of high-energy backscattered electrons. The observation field should be selected to cover areas where the curvature of the toner particles is small.

[0186] (Conditions for acquiring elemental mapping images of toner particles) After acquiring the secondary electron and backscattered electron images described above, an elemental mapping image of the toner particles was acquired using SEM-EDX in the same field of view as the secondary electron and backscattered electron images. The conditions for acquiring the elemental mapping image were as follows. EDX detector: JEOL JED-2300T Dry SD100GV detector (detection element area: 100mm²) 2 ) EDS analyzer: Thermo Fisher Scientific NORAN System 7 Drift correction coefficient: 4 Dwell Time: 30μs Total number of frames: 100 X-ray CountRate:4000~10000cps Elemental mapping image size: 256 x 256 pixels

[0187] The spectral mapping data collected under the above conditions was used to extract quantitative map images for each element (Ti, Sr, Ba, Ca, Si, Al, O) using the quantitative map mode in the NORAN System7 measurement command described above. The settings used were as follows: • Kernel size: 3x3 • Quantitative map setting: High (slow) • Filter fit type: High precision (slow)

[0188] (Method for calculating the minimum diameter and coverage area ratio of primary particles) First, secondary electron images and backscattered electron images of the toner particle surface are acquired in the same field of view. In the backscattered electron image acquired under the above conditions, fine particles present on the toner particle surface can be easily identified from the brightness threshold at each pixel. For example, • Brightness threshold of metal titanate compound nanoparticles (175-200 (256 gradations, reference value)) • Brightness threshold of silica microparticles (85-128 (256 gradations, reference value)) • Brightness threshold of titania particles (140-160 (256 gradations, reference value)) • Brightness threshold of alumina nanoparticles (75-115 (256 gradations, reference value))

[0189] Subsequently, elemental mapping images are acquired for each element within the same field of view as the secondary electron image and backscattered electron image, and these elemental mapping images are superimposed. In the superimposed elemental mapping image, areas where Ti and Sr, Ba and Ca, etc., overlap indicate that these are titanium titanate compound nanoparticles present on the toner particle surface. Next, nanoparticles other than titanium titanate compound nanoparticles present on the toner particle surface are identified. In the superimposed elemental mapping image, areas where Si and O overlap indicate silica nanoparticles, areas where Ti and O overlap indicate titania nanoparticles, and areas where Al and O overlap indicate alumina nanoparticles.

[0190] The minimum Ferret diameter of the primary particle in each microparticle can be calculated by analyzing the backscattered electron image of the toner particles obtained above using the image processing software ImageJ (developed by Wayne Rashand). The calculation procedure is shown below.

[0191] First, convert the backscattered electron image to 8-bit using the Type option in the Image menu. Next, reduce image noise by setting the Median diameter to 2.0 pixels using the Filters option in the Process menu. Then, select the entire backscattered electron image using the Rectangle Tool on the toolbar. Subsequently, select Threshold from the Adjust option in the Image menu and adjust it to match the brightness threshold for the backscattered electron image described above. Furthermore, select Analyze Particles from the Analyze menu, select Masks as the output image, and output a binarized image separated for each particle. If it is difficult to separate each particle using the brightness threshold in the backscattered electron image, identify the positions corresponding to the titanate metal compound particles, silica particles, titania particles, and alumina particles from the elemental mapping image and binarized image measured in the same field of view, and divide the binarized image for each particle. Overlay the obtained binarized image with the secondary electron image measured in the same field of view, identify the contours of the particles using the secondary electron image, and then output a binarized image separated for each particle.

[0192] Select the binarized image output above, then select Area and Ferret's diameter from Set Measurements in the Analyze menu, and run Measure in the Analyze menu to obtain the Ferret's minimum diameter (nm) and area (nm) of the primary particles in each microparticle. 2 The minimum Ferret diameter of primary particles in each obtained microparticle is counted at 2 nm intervals, and a particle size distribution graph is created with the minimum Ferret diameter of primary particles on the horizontal axis and frequency on the vertical axis. In the obtained particle size distribution graph, the median value of the minimum Ferret diameter at which the frequency is maximum is taken as the peak value (nm). In addition, the ratio of the total area of ​​primary particles in each microparticle present in the binarized image to the total area of ​​the binarized image is taken as the coverage area percentage (area %) of each microparticle.

[0193] If inorganic nanoparticle C is silica nanoparticle, the Ferret minimum diameter (nm) and area (nm) of the primary particles of silica nanoparticle B and inorganic nanoparticle C can be determined using the following procedure. 2) is calculated. In the particle size distribution of silica nanoparticles created by the above method, the peak value with the highest frequency and the peak value with the second highest frequency are identified. Of the above two peak values, the peak value with the smaller diameter is the minimum Ferret diameter D of the primary particle of silica nanoparticle B. B The peak value on the large diameter side is the minimum diameter D of the primary particle of inorganic fine particles C. C The following steps are taken. The minimum Ferret diameter at which the frequency is minimized between the two peak values ​​mentioned above is used as the threshold. Particles with a minimum Ferret diameter smaller than the threshold are defined as silica nanoparticles B, and particles with a minimum Ferret diameter greater than or equal to the threshold are defined as silica nanoparticles C (inorganic nanoparticles). After separating silica nanoparticles B and silica nanoparticles C (inorganic nanoparticles) using the above method, the area and coverage area ratio of each type of nanoparticle are calculated.

[0194] The above procedure is performed for each toner particle under evaluation across 20 fields of view. The arithmetic mean of the 20 calculated values ​​obtained is taken as the peak value for each microparticle and the coverage area ratio of each microparticle relative to the toner particle.

[0195] <Solid form of metal titanate compound fine particles A> 29 Si-NMR CP-MAS measurement method> The titanate metal compound fine particles A separated above were used as a sample. 29 Si-NMR CP / MAS measurements will be performed. The measurement equipment and conditions are as follows. Equipment: JNM-ECX5002 (JEOL RESONANCE) Temperature: room temperature Measurement method: CP / MAS method 29 Si 45° Sample tube: Zirconia 8.0 mmφ Sample: Filled in a test tube in powder form. Sample rotation speed: 10kHz Relaxation delay: 180s Scan: 2000 Calibration standard material: DSS (3-(trimethylsilyl)-1-propanesulfonate sodium)

[0196] Solid sample using metal titanate compound fine particles A 29Solid obtained by Si-NMR CP / MAS measurement 29 The Si-NMR spectrum is separated by curve fitting to determine which peak D belongs to the D unit structure and which peak T belongs to the T unit structure, based on the different substituents and bonding groups of the silane components.

[0197] Curve fitting is performed using the NMR analysis software "Delta Software" manufactured by JEOL Ltd. First, load the measurement data by clicking "1D Pro" from the menu icon. Next, select "Curve fitting function" from the "Command" menu bar to perform curve fitting. Curve fitting is performed for each component so that the difference between the synthesized peak (the combined peak obtained by curve fitting) and the peak in the measurement data (synthesized peak difference) is minimized. D unit: (R g )(R h )Si(O 1 / 2 )2 formula (5) T unit: R m si(O 1 / 2 )3 formula (6)

[0198] In formulas (5) to (6), R g , R h , R m This indicates a hydrocarbon group with one or more carbon atoms, a halogen atom, etc., that is bonded to silicon.

[0199] Peak D is located in the chemical shift range of -25 ppm to -15 ppm. The area of ​​Peak D in the chemical shift range of -30 ppm to 0 ppm is defined as S. D Let it be so. Furthermore, S D is a solid 29 This is the integral value of the region between the Si-NMR spectrum and the baseline. The baseline is the line segment connecting the plot of intensity value B1 at a chemical shift of 50 ppm and the plot of intensity value B2 at a chemical shift of -110 ppm, where B1 is the arithmetic mean of intensity values ​​at chemical shifts of 40 ppm to 60 ppm, and B2 is the arithmetic mean of intensity values ​​at chemical shifts of -120 ppm to -100 ppm.

[0200] Peak T is located in the chemical shift range of -70 ppm to -50 ppm. Further using the Voigt function, peak T is separated into peak X2, located in the range of -60 ppm to -50 ppm, and peak X3, located in the range of -70 ppm to -60 ppm. For peaks X2 and X3, the area of ​​peak X2 in the chemical shift range of -60 ppm to -40 ppm is defined as S. X2 The integral value of peak X3 in the chemical shift range of -80 ppm to -60 ppm is S. X3 Let it be so. Furthermore, S X2 and S X3 is a solid 29 This is the integral value of the region between the Si-NMR spectrum and the baseline mentioned above. D S X2 S X3 From, S D / (S X2 +S X3 Calculate ).

[0201] <Method for measuring fragment ions on the surface of metal titanate compound nanoparticles using time-of-flight secondary ion mass spectrometry (TOF-SIMS)> In TOF-SIMS measurement, the titanate metal compound fine particles A, separated from the toner by the method described above, are used as the sample. The measurement device used is the TRIFT-IV manufactured by ULVAC-PHIE. The measurement conditions are as follows. Sample preparation: Fine particles of metal titanate compound A are attached to an indium sheet. Primary ion: Au ion Acceleration voltage: 30kV Charge neutralization mode: On Measurement mode: Positive Raster: 200 μm Measurement time: 60s

[0202] From the obtained mass profile of secondary ion mass / secondary ion charge number (m / z), we check whether fragment ions corresponding to the structure represented by equation (1) are observed. For example, if the surface treatment agent is polydimethylsiloxane, fragment ions are observed at positions such as m / z = 147, 207, and 221.

[0203] <Method for measuring the average circularity of toner> The average circularity of the toner is measured and analyzed using a flow-type particle image analyzer (product name: FPIA-3000, manufactured by Sysmex Corporation) under the following conditions. The specific measurement method is as follows.

[0204] First, put 20 mL of deionized water, from which impurities and other contaminants have been removed, into a glass container. Add 0.2 mL of a diluted solution of (product name: Contaminon N, manufactured by Wako Pure Chemical Industries, Ltd.: a 10% by mass aqueous solution of a pH 7 neutral detergent for cleaning precision measuring instruments consisting of a nonionic surfactant, anionic surfactant, and organic builder) diluted three times by mass with deionized water as a dispersant.

[0205] Furthermore, 0.02 g of the sample to be measured is added and dispersed for 2 minutes using an ultrasonic disperser to prepare the dispersion for measurement. During this process, the dispersion is cooled as appropriate so that its temperature is between 10°C and 40°C. As the ultrasonic disperser, a tabletop ultrasonic cleaner disperser with an oscillation frequency of 50 kHz and an electrical output of 150 W (for example, "VS-150" (manufactured by Velvo-Clear Co., Ltd.)) is used, and a predetermined amount of deionized water is placed in the water tank, to which 2 mL of the aforementioned Contaminon N is added.

[0206] For the measurement, a flow-type particle image analyzer equipped with a "UPlanApro" objective lens (magnification 10x, numerical aperture 0.40) was used, and a particle sheath (product name: PSE-900A, manufactured by Sysmex Corporation) was used as the sheath solution. The dispersion solution prepared according to the above procedure was introduced into the flow-type particle image analyzer, and 3000 toner particles were measured in HPF measurement mode and total count mode. Then, the binarization threshold for particle analysis was set to 85%, and the analyzed particle size was limited to an equivalent circle diameter of 1.985 μm or more and less than 39.69 μm, and the average circularity of the toner particles was determined.

[0207] Before starting the measurement, autofocus adjustment is performed using standard latex particles (for example, Duke Scientific's "RESEARCH AND TEST PARTICLES Latex Microsphere Suspensions 5200A" diluted with deionized water).

[0208] <Measurement of carbon atom content (C amount) of titanate metal compound fine particles A> The amount of carbon (C) derived from the treatment agent for the titanate metal compound fine particles A is measured using a carbon-sulfur analyzer (product name: EMIA-320) manufactured by HORIBA Corporation.

[0209] 0.3 g of the sample, metal titanate compound fine particles A, is accurately weighed and placed in the crucible for the carbon-sulfur analyzer described above. To this, 0.3 ± 0.05 g of tin (replacement part number 9052012500) and 1.5 ± 0.1 g of tungsten (replacement part number 9051104100) are added as combustion aids.

[0210] Subsequently, the titanate metal compound fine particles are heated at 1100°C in an oxygen atmosphere according to the instructions for use of the carbon-sulfur analyzer. This causes the hydrophobic groups derived from the hydrophobic treatment agent on the surface of the titanate metal compound fine particles A to decompose into CO2, and the amount of CO2 is measured. The amount of carbon (mass%) contained in the titanate metal compound fine particles A is determined from the amount of CO2 obtained. [Examples]

[0211] The toners of this disclosure will be described in detail below using examples and comparative examples, but this disclosure is not limited to these examples. In the following descriptions of examples, "parts" refers to mass unless otherwise specified.

[0212] <Example of manufacturing of metal titanate compound fine particles A1> Metatitanic acid produced by the sulfuric acid method was subjected to iron removal and bleaching treatment, then desulfurized by adding a 3 mol / L sodium hydroxide aqueous solution to bring the pH to 9.0, followed by neutralization to pH 5.6 with 5 mol / L hydrochloric acid and filtration and washing. Water was added to the washed cake to form a slurry of TiO2 with a pH of 1.90 mol / L, and then hydrochloric acid was added to bring the pH to 1.4 and perform gelatinization treatment.

[0213] 1.90 moles of desulfurized and disintegrated metatitanic acid were taken as TiO2 and placed in a 3 L reaction vessel. To the disintegrated metatitanic acid slurry, 2.185 moles of strontium chloride aqueous solution were added to achieve a SrO / TiO2 molar ratio of 1.15, and the TiO2 concentration was adjusted to 1.039 mol / L. Next, the mixture was heated to 90°C while stirring, and then 440 mL of 10 mol / L sodium hydroxide aqueous solution was added over 40 minutes. After that, stirring was continued at 95°C for 30 minutes, and then the mixture was rapidly cooled in ice water to terminate the reaction.

[0214] The reaction slurry was heated to 70°C, 12 mol / L hydrochloric acid was added until the pH reached 5.0, and stirring continued for 1 hour. The resulting precipitate was decanted. The slurry containing the precipitate was adjusted to 40°C, hydrochloric acid was added to adjust the pH to 2.5, and then 5.0% by mass of isobutyltrimethoxysilane relative to the solid content was added and the mixture was stirred for 10 hours. After that, the viscosity was 1.0 × 10⁻⁶. -3 m 2 Dimethyl silicone oil at a concentration of 2.0% by mass relative to the solid content was added, and the mixture was stirred for 10 hours. A 5 mol / L aqueous sodium hydroxide solution was added to adjust the pH to 6.5, and stirring was continued for 1 hour. After filtration and washing, the resulting cake was dried in air at 120°C for 8 hours to obtain metal titanate compound fine particles A1. The physical properties of the obtained metal titanate compound fine particles A1 are shown in Table 1.

[0215] <Manufacturing examples of metal titanate compound fine particles A2-A24> In the example of producing metal titanate compound nanoparticles A1, the production was carried out in the same manner except that the metal atoms of the metal titanate compound nanoparticle substrate, the type and amount of silane coupling agent, and the amount of silicone oil were changed as shown in Table 1, to obtain metal titanate compound nanoparticles A2 to A24. The physical properties are shown in Table 1.

[0216] <Examples of titanium dioxide nanoparticle manufacturing> 50 g of titanium dioxide nanoparticles (titanium dioxide nanoparticle substrate) with a number-average particle size of 30 nm was dispersed in 500 mL of deionized water. The pH of the resulting titanium dioxide nanoparticle dispersion was adjusted to between 3 and 4 by adding 5 mol / L hydrochloric acid. To the pH-adjusted titanium dioxide nanoparticle dispersion, 5.0% by mass of isobutyltrimethoxysilane relative to the solid content was added and the mixture was stirred for 10 hours. Afterward, the viscosity was adjusted to 1.0 × 10⁻⁶. -3 m 2 Dimethyl silicone oil at 2.0% by mass relative to the solid content was added, and the mixture was stirred for 10 hours. The dispersion of titanium dioxide nanoparticles after stirring was transferred to a 1 L separable flask. Subsequently, the dispersion of titanium dioxide nanoparticles in the flask was reacted at 70°C for 30 minutes. Then, a 5 mol / L sodium hydroxide aqueous solution was added to adjust the pH to 6.5, and stirring was continued for 1 hour. After filtration and washing, the resulting cake was dried in air at 120°C for 8 hours to obtain titanium dioxide nanoparticle 1. The physical properties of the obtained titanium dioxide nanoparticle 1 were as follows: C content 1.60 (mass%), S D 1.00, S X2 1.30, S X3 1.60, S D / (S X2 +S X3 The value was 0.34.

[0217] [Table 1]

[0218] The abbreviations in Table 1 are as follows: Sr: Strontium Ba: Barium

[0219] <Example of manufacturing silica microparticles B1> Untreated dry silica (fumed silica, BET specific surface area 200 m²) 2 The silica ( / g) was placed in a reactor and heated to 330°C while being stirred to a fluid state. Subsequently, as a surface treatment agent, 20 parts of dimethyl silicone oil (polydimethylsiloxane: KF-96-50CS, manufactured by Shin-Etsu Chemical Co., Ltd.) was sprayed onto 100 parts of untreated dry silica. After that, heating and stirring were continued for 1 hour to coat the silica, and silica fine particles B1 were obtained. The physical properties of the obtained silica fine particles B1 are shown in Table 2.

[0220] <Manufacturing examples of silica microparticles B2-B6> In the example of producing silica nanoparticles B1, the same procedure was followed except that the BET specific surface area of ​​untreated dry silica and the amount of surface treatment agent were changed as shown in Table 2, to obtain silica nanoparticles B2 to B6. The physical properties are shown in Table 2.

[0221] [Table 2]

[0222] <Example of manufacturing inorganic fine particles C1> Untreated dry silica (fumed silica, BET specific surface area 30 m²) 2 The silica ( / g) was placed in a reactor and heated to 330°C while being stirred to a fluid state. Subsequently, as a surface treatment agent, 20 parts of dimethyl silicone oil (polydimethylsiloxane: KF-96-50CS, manufactured by Shin-Etsu Chemical Co., Ltd.) were sprayed onto 100 parts of untreated dry silica. After that, heating and stirring were continued for 1 hour to coat the silica, and inorganic fine particles C1 were obtained. The physical properties of the obtained inorganic fine particles C1 are shown in Table 3.

[0223] <Examples of manufacturing inorganic fine particles C2-C7> In the example of producing inorganic fine particles C1, the properties of inorganic fine particles C2 to C7 were obtained in the same manner as in the example of producing inorganic fine particles C1, except that the type of fine particle substrate and the BET specific surface area were changed as shown in Table 3.

[0224] [Table 3]

[0225] <Example of Polyester Resin D1 Manufacturing> 100 parts by mass of a mixture of raw material monomers other than trimellitic anhydride, mixed in the charging ratios shown in Table 4, and 0.55 parts by mass of tin(II) 2-ethylhexanoate as a catalyst were placed in a 6-liter four-necked flask equipped with a nitrogen inlet tube, a dehydration tube, a stirrer, and a thermocouple, and reacted under a nitrogen atmosphere at 200°C for 6 hours. Furthermore, 1.8 parts by mass of trimellitic anhydride were added at 210°C, and the reaction was carried out under reduced pressure of 40 kPa until the weight-average molecular weight (Mw) reached 12100. The resulting polyester resin was designated as polyester resin D1.

[0226] <Example of Polyester Resin D2 Manufacturing> Polyester resin D2 was obtained in the same manner as the production example of polyester resin D1, except that the raw material monomers were changed as shown in Table 4. The physical properties are shown in Table 4.

[0227] [Table 4]

[0228] The abbreviations in Table 4 are as follows: TPA: Terephthalic acid TMA: Trimellitus anhydride BPA-PO: Propylene oxide adduct of bisphenol A (average number of moles added: 2.0 mol) EG: Ethylene glycol

[0229] <Manufacturing example of electrostatically controlled resin E> 9.2 g of the polymerizable monomer shown in structural formula (9) below and 60.1 g of styrene were dissolved in 42.0 ml of DMF, stirred for 1 hour while bubbling with nitrogen, and then heated to 110°C. To this reaction solution, a mixture of 2.1 g of tert-butyl peroxyisopropyl monocarbonate (manufactured by Nippon Oil & Fats Co., Ltd., trade name Perbutyl I) and 42 ml of toluene was added dropwise as an initiator. After the addition was complete, the reaction was carried out at 110°C for 4 hours. Subsequently, the cooled reaction solution was added dropwise to 1 L of methanol to obtain a precipitate. The obtained precipitate was dissolved in 120 ml of THF, then added dropwise to 1.80 L of methanol to precipitate a white precipitate, filtered, and dried under reduced pressure at 90°C to obtain the electrostatically controlled resin E.

[0230] [ka]

[0231] <Example of toner particle 1 manufacturing> Toner particles 1 were manufactured according to the following procedure.

[0232] (Preparation of pigment masterbatch) The following materials were placed in an attritor (Mitsui Miike Chemical Machinery Co., Ltd.), and then dispersed using 1.7 mm diameter zirconia particles at 220 rpm for 5 hours to obtain a pigment masterbatch. • Styrene 60.0 parts • Cyan pigment (manufactured by Dainichi Seika Co., Ltd., CIPigment Blue 15:3) 7 parts

[0233] (Preparation of the first water system medium) 353.8 parts of deionized water were mixed with 2.9 parts of sodium phosphate dodecahydrate and heated to 60°C while stirring using a TK-type homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.). Then, a calcium chloride aqueous solution was prepared by adding 1.7 parts of calcium chloride dihydrate to 11.7 parts of deionized water, and a magnesium chloride aqueous solution was prepared by adding 0.5 parts of magnesium chloride to 15.0 parts of deionized water. The mixture was stirred to obtain a first aqueous medium containing a dispersion stabilizer.

[0234] (Preparation of polymerizable monomer compositions) • Styrene 15.0 parts n-butyl acrylate 25.0 parts • Bifunctional ester wax (ethylene glycol distearate) 5.0 parts • Hydrocarbon wax (melting point: 79°C) 5.0 parts • Pigment masterbatch 67.0 units • Polyester resin D1 3.0 parts • Charging control resin E 0.5 part

[0235] The above materials were uniformly dispersed and mixed using an attritor (manufactured by Mitsui Miike Chemical Machinery Co., Ltd.), then heated to 60°C and dissolved to obtain a polymerizable monomer composition.

[0236] (Preparation of the second water system medium) 166.8 parts of deionized water were mixed with 0.6 parts of sodium phosphate dodecahydrate and heated to 60°C while stirring with a paddle agitator. Then, a calcium chloride aqueous solution was added by adding 0.3 parts of calcium chloride dihydrate to 2.3 parts of deionized water and stirring was continued to obtain a second aqueous medium containing a dispersion stabilizer.

[0237] (granulation) The polymerizable monomer composition was added to the first aqueous medium described above. This granulated liquid was processed using a Cavitron (manufactured by Eurotech) at a rotor speed of 29 m / s for 1 hour to uniformly disperse and mix the mixture. Further, 7.0 parts of t-butyl peroxypivalate were added as a polymerization initiator, and the mixture was granulated at 60°C under an N2 atmosphere using a Creamix (manufactured by M-Technic) at a peripheral speed of 22 m / s for 10 minutes while stirring, to obtain a granulated liquid containing droplets of the polymerizable monomer composition.

[0238] (polymerization / distillation / drying) The granulated liquid was added to the second aqueous medium described above, and the mixture was reacted at 74°C for 3 hours while being stirred with a paddle agitator. After the reaction was complete, the temperature was raised to 98°C and the mixture was distilled for 3 hours to obtain a reaction slurry. Subsequently, as a cooling step, water at 0°C was added to the reaction slurry, and the slurry was cooled from 98°C to 45°C at a rate of 100°C / min. After that, the temperature was raised further and the mixture was held at 50°C for 3 hours.

[0239] The reaction slurry was then allowed to cool to room temperature at 25°C. The cooled reaction slurry was washed with hydrochloric acid, filtered, and dried to obtain toner particles 1 with a weight-average particle size of 7.5 μm.

[0240] <Example of toner particle 2 manufacturing> In the example of manufacturing toner particle 1, toner particle 2 with a weight-average particle size of 7.6 μm was obtained in the same manner as toner particle 1, except that polyester resin D1 was changed to polyester resin D2.

[0241] <Example of toner particle 3 manufacturing> (Preparation of styrene-acrylic resin particle dispersion) • Styrene 75 units n-butyl acrylate 25 parts

[0242] To the mixture of the above materials, a solution of 1.0 part of anionic surfactant (Dowfax, manufactured by Dow Chemical) dissolved in 60 parts of deionized water was added and dispersed in a flask to create an emulsion of monomers. Subsequently, 2.0 parts of anionic surfactant (Dowfax, manufactured by Dow Chemical) was dissolved in 90 parts of deionized water, and 2.0 parts of the monomer emulsion was added to it. Furthermore, 10 parts of deionized water in which 1.0 part of ammonium persulfate was dissolved was added.

[0243] Subsequently, the remaining monomer emulsion was added over 3 hours, and the flask was purged with nitrogen. The solution in the flask was then heated in an oil bath to 65°C while stirring, and emulsion polymerization was continued for 5 hours to obtain a styrene-acrylic resin particle dispersion. The solid content of the styrene-acrylic resin particle dispersion was adjusted to 20% by mass by adding ion-exchanged water.

[0244] (Preparation of a dispersion of coloring agent particles) • Cyan pigment (manufactured by Dainichi Seika Co., Ltd., CIPigment Blue 15:3) 35 parts • Anionic surfactant (manufactured by Daiichi Kogyo Seiyaku Co., Ltd., Neogen®) 2 parts 250 bottles of deionized water

[0245] The above materials were mixed and dissolved, and dispersed for about 1 hour using a high-pressure impact disperser Ultimizer (HJP30006, manufactured by Sugino Machine Co., Ltd.) to obtain a colorant particle dispersion. The volume-average particle size of the particles in this colorant particle dispersion was 150 nm. Subsequently, deionized water was added to adjust the solid content concentration to 20% by mass.

[0246] (Preparation of mold release agent particle dispersion) • Paraffin wax (manufactured by Nippon Seiro Co., Ltd., HNP-9) 200 copies • Anionic surfactant (Neogen RK, manufactured by Daiichi Kogyo Seiyaku) 10.0 parts • Ion-exchanged water 20.0 parts

[0247] The above materials were mixed, and the release agent was dissolved in a pressure-discharge homogenizer (Gorin homogenizer, manufactured by Gorin Corporation) at an internal liquid temperature of 120°C. The mixture was then dispersed at a dispersion pressure of 5 MPa for 120 minutes, followed by 40 MPa for 360 minutes, and then cooled to obtain a dispersion. Deionized water was added to adjust the solid content to 20% by mass, and this was used as the release agent particle dispersion.

[0248] (Manufacturing of toner particles 3) • Styrene-acrylic resin particle dispersion, 375 parts • Coloring agent particle dispersion 75 parts • Release agent particle dispersion 15 parts • 750 units of deionized water • Anionic surfactant (Dowfax 2A1, manufactured by Dow Chemical) 3.2 parts

[0249] The above materials were placed in a 3-liter reaction vessel equipped with a thermometer, pH meter, and stirrer as the core-forming material. After adjusting the pH to 3.0 by adding 1.0% nitric acid at a temperature of 25°C, the mixture was dispersed at 5,000 rpm using a homogenizer (IKA Ultra-Turrax T50) while 100 parts of a 2.0% by mass aqueous magnesium chloride solution were added as a flocculant and dispersed for 6 minutes.

[0250] Subsequently, the mixture was heated to 53°C in a heating water bath, with the rotation speed adjusted as needed to ensure proper agitation. The volume-average particle size of the formed aggregated particles was checked periodically using a Coulter Multisizer III. When the volume-average particle size reached 5.0 μm, the temperature was maintained, and the pH was adjusted to 9.0 using a 5% sodium hydroxide aqueous solution. The temperature was then raised to 90°C and maintained at 90°C for 1 hour to fuse the aggregated particles.

[0251] Subsequently, hydrochloric acid was added to adjust the pH to 5.0 at 90°C, and the mixture was stirred for another 30 minutes. Next, a 0.9 mol / L Na2CO3 aqueous solution was added to adjust the pH to 5.5, and the mixture was held for 30 minutes. After cooling to 25°C, the mixture was filtered and solid-liquid separated, followed by washing with deionized water. After washing, the mixture was dried using a vacuum dryer to obtain toner particles 3 with a weight-average particle size of 7.3 μm.

[0252] <Example of manufacturing of binder resin L> Polyoxypropylene (2,2)-2,2-bis(4-hydroxyphenyl)propane: 72.0 parts by mass (0.20 moles; 100.0 mol% of the total number of moles of polyhydric alcohols) Terephthalic acid: 28.0 parts by mass (0.17 moles; 100.0 mol% of the total number of moles of polycarboxylic acid) • Tin 2-ethylhexanoate (esterification catalyst): 0.5 parts by mass

[0253] The above materials were weighed into a reaction vessel equipped with a condenser, stirrer, nitrogen inlet tube, and thermocouple. Next, the flask was purged with nitrogen gas, and the temperature was gradually increased while stirring. The reaction was carried out at 200°C for 4 hours while stirring. Furthermore, the pressure in the reaction vessel was reduced to 8.3 kPa and maintained for 1 hour, after which it was cooled to 180°C and returned to atmospheric pressure. • Trimellitus anhydride: 1.3 parts by mass (0.01 moles; 4.0 mol% of the total number of moles of polycarboxylic acid) • tert-butylcatechol (polymerization inhibitor): 0.1 parts by mass

[0254] Subsequently, the above materials were added, the pressure in the reaction vessel was reduced to 8.3 kPa, and the reaction was allowed to proceed for 1 hour while maintaining the temperature at 180°C. After confirming that the softening point, measured according to ASTM D36-86, reached 90°C, the temperature was lowered to stop the reaction and obtain the binder resin L.

[0255] <Example of manufacturing of binder resin H> Polyoxypropylene (2,2)-2,2-bis(4-hydroxyphenyl)propane: 72.3 parts by mass (0.20 moles; 100.0 mol% of the total number of moles of polyhydric alcohols) Terephthalic acid: 18.3 parts by mass (0.11 molar parts; 65.0 mol% of the total number of moles of polycarboxylic acid) Fumaric acid: 2.9 parts by mass (0.03 molar parts; 15.0 mol% of the total number of moles of polycarboxylic acid) • Tin 2-ethylhexanoate (esterification catalyst): 0.5 parts by mass

[0256] The above materials were weighed into a reaction vessel equipped with a condenser, stirrer, nitrogen inlet tube, and thermocouple. Next, the flask was purged with nitrogen gas, and the temperature was gradually increased while stirring. The mixture was then reacted at 200°C while stirring for 2 hours.

[0257] Furthermore, the pressure inside the reaction vessel was reduced to 8.3 kPa and maintained for one hour, then cooled to 180°C and returned to atmospheric pressure. • Trimellitus anhydride: 6.5 parts by mass (0.03 molar parts; 20.0 mol% of the total number of moles of polycarboxylic acid) • tert-butylcatechol (polymerization inhibitor): 0.1 parts by mass

[0258] Subsequently, the above materials were added, the pressure in the reaction vessel was reduced to 8.3 kPa, and the reaction was carried out for 15 hours while maintaining the temperature at 160°C. After confirming that the softening point, measured according to ASTM D36-86, reached 137°C, the temperature was lowered to stop the reaction and obtain the binder resin H.

[0259] <Example of toner particle 4 manufacturing> • Binding resin L 70 parts by mass • Binding resin H 30 parts by mass Fischer-Tropsch wax (Hydroxide wax, peak temperature of maximum endothermic peak 90°C) 5 parts by mass CI Pigment Blue 15:3 5 parts by mass

[0260] First, the above materials were pre-mixed in a Henschel mixer, and then melt-kneaded using a twin-screw extruder. At this time, the residence time was adjusted so that the temperature of the kneaded resin reached 140°C. The resulting kneaded material was cooled, coarsely ground in a hammer mill, and then ground in a turbo mill. The resulting fine particles were classified using a multi-part classifier utilizing the Coanda effect (product name: Elbow Jet Classifier, manufactured by Nippon Steel Mining Co., Ltd.) to obtain toner particles 4 with a weight-average particle size of 6.5 μm.

[0261] <Example of Toner 1 manufacturing> For every 100.0 parts of toner particles, 0.30 parts of metal titanate compound fine particles A1, 0.80 parts of silica fine particles B1, and 0.25 parts of inorganic fine particles C2 were added and mixed externally using FM10C (manufactured by Nippon Coke Industries Co., Ltd.). The external addition conditions were as follows: the upper blade was set to Y0, the lower blade to S0, the distance from the deflector wall was set to 20 mm, and the rotation speed was 66.6 s. -1 The toner was added for 10 minutes using cooling water at a temperature of 20°C and a flow rate of 10 L / min. Afterwards, it was sieved through a mesh with a mesh size of 200 μm to obtain toner 1. The physical properties of the obtained toner 1 are shown in Tables 5-1 and 5-2.

[0262] Furthermore, SEM image analysis and EDX analysis of Toner 1 confirmed that the main particles constituting peak 1 are silica microparticles B, the main particles constituting peak 2 are inorganic microparticles C, and the main particles constituting peak 3 are metal titanate compound microparticles A.

[0263] <Manufacturing examples for toners 2-40 and 42> Except for changing the combination of toner particles and external additives as shown in Tables 5-1 and 5-2, toners 2-40 and 42 were obtained in the same manner as in the manufacturing example of toner 1. The physical properties are shown in Tables 5-1 and 5-2.

[0264] Furthermore, SEM image analysis and EDX analysis of toners 2-37, 40, and 42 confirmed that the main particles constituting peak 1 are silica microparticles B, the main particles constituting peak 2 are inorganic microparticles C, and the main particles constituting peak 3 are metal titanate compound microparticles A. SEM image analysis and EDX analysis of toner 38 confirmed that the main particles constituting peak 1 are silica microparticles B, and the main particles constituting peak 3 are metal titanate compound microparticles A. SEM image analysis and EDX analysis of toner 39 confirmed that the main particles constituting peak 2 are inorganic microparticles C, and the main particles constituting peak 3 are metal titanate compound microparticles A.

[0265] <Example of Toner 41 Manufacturing> For every 100.0 parts of toner particles, titanium dioxide fine particles 1 (0.30 parts), silica fine particles B1 (0.80 parts), and inorganic fine particles C1 (0.25 parts) were added and mixed externally using FM10C (manufactured by Nippon Coke Industries Co., Ltd.). The external addition conditions were as follows: the lower blade was set to A0, the distance from the deflector wall was set to 20 mm, the amount of toner particles 1 added was 2.0 kg, and the rotation speed was 66.6 s. -1 The toner was added for 10 minutes using cooling water at a temperature of 20°C and a flow rate of 10 L / min. Afterward, the mixture was sieved through a 200 μm mesh to obtain toner 41. The physical properties of the obtained toner 41 are shown in Tables 5-1 and 5-2.

[0266] Furthermore, SEM image analysis and EDX analysis of toner 41 confirmed that the main particles constituting peak 1 are silica microparticles B, and the main particles constituting peak 2 are inorganic microparticles C.

[0267] [Table 5-1]

[0268] [Table 5-2]

[0269] <Examples 1-33, Comparative Examples 1-9> Evaluation was performed using toners 1-42 under the conditions described below. The evaluation results are shown in Table 6. A modified HP Color LaserJet Enterprise M653 with a process speed of 410 mm / sec was used as the evaluation machine. Vitality paper (manufactured by Xerox, basis weight 75 g / cm²) was used as the evaluation paper. 2 (Letter size) was used.

[0270] <Evaluation of static charge build-up in high-temperature, high-humidity environments> The evaluation machine and a toner cartridge filled with evaluation toner were left in a high-temperature, high-humidity environment of 32.5℃ / 80%RH for more than one day. Then, 1000 test charts (vertical letter format) with a print ratio of 1% were printed using the evaluation machine. After printing 1000 sheets, the charge amount (μC / g) of the toner on the developer carrier inside the toner cartridge was measured using a blow-off powder charge amount measuring device TB-200 (manufactured by Toshiba Chemical Co., Ltd.). The obtained toner charge amount is defined as C1 (μC / g).

[0271] After leaving the samples in the same environment for 72 hours, 100 test charts (letter portrait orientation) with a print ratio of 1% were printed using the evaluation machine. After printing the 100 sheets, the charge amount (μC / g) of the toner on the developer carrier inside the toner cartridge was measured using a blow-off powder charge amount measuring device TB-200 (manufactured by Toshiba Chemical Co., Ltd.). The obtained toner charge amount was defined as C2 (μC / g).

[0272] Using the obtained C1 and C2 values, the ratio of C2 to C1 (%) was calculated, and the charge rise performance was evaluated according to the following criteria. A higher ratio of C2 to C1 (%) indicates a toner with better charge rise performance.

[0273] [Evaluation Criteria] A: Over 95% B: 90% or more but less than 95% C: 85% to less than 90% D: Less than 85%

[0274] <Evaluation of static charge retention in high-temperature, high-humidity environments> The evaluation machine and a toner cartridge filled with evaluation toner were left in a high-temperature, high-humidity environment of 32.5°C / 80%RH for more than one day. Then, 100 test charts (vertical letter format) with a print ratio of 1% were printed using the evaluation machine. After printing 100 sheets, the charge amount (μC / g) of the toner on the developer carrier inside the toner cartridge was measured using a blow-off powder charge amount measuring device TB-200 (manufactured by Toshiba Chemical Co., Ltd.). The obtained toner charge amount was defined as the initial charge amount C3 (μC / g).

[0275] Next, 50,000 test charts (letter portrait orientation) with a print ratio of 1% were printed using the evaluation machine. After printing 50,000 sheets, the charge amount (μC / g) of the toner on the developer carrier inside the toner cartridge was measured using a blow-off powder charge amount measuring device TB-200 (manufactured by Toshiba Chemical Co., Ltd.). The obtained toner charge amount was defined as the endurance charge amount C4 (μC / g).

[0276] Using the obtained C3 and C4 values, the difference between the initial charge and the charge after durability (C3-C4) was calculated, and the charge retention performance was evaluated according to the following criteria.

[0277] [Evaluation Criteria] AA: Difference between initial charge and charge after endurance is less than 1.0 μC / g A: The difference between the initial charge and the charge after endurance is 1.0 μC / g or more and less than 1.5 μC / g. B: The difference between the initial charge and the charge after endurance is 1.5 μC / g or more, and less than 2.5 μC / g. C: The difference between the initial charge and the charge after endurance is 2.5 μC / g or more, and less than 4.5 μC / g. D: The difference between the initial charge and the charge after endurance is 4.5 μC / g or more.

[0278] <Evaluation of streaks in paper transport direction in high temperature and high humidity environments> After leaving the evaluation machine and toner cartridge filled with evaluation toner in a high-temperature, high-humidity environment of 32.5℃ / 80%RH for more than one day, the evaluation machine printed 100,000 horizontal line images with a print density of 0.1%. During this process, one full-color image (letter portrait) was printed for every 5,000 horizontal line images with a print density of 0.1%. The printed full-color images were visually observed, and streaks in the paper transport direction were evaluated according to the following criteria.

[0279] [Evaluation Criteria] A: No streaks appear in solid images in the paper transport direction even after printing 100,000 horizontal line images. B: No streaks in the paper transport direction appeared on solid images until 80,000 horizontal line images were printed, but streaks appeared on solid images after 85,000 to 100,000 prints. C: No streaks in the paper transport direction appeared on solid images until 50,000 horizontal line images were printed, but streaks appeared on solid images after 55,000 to 80,000 prints. D: No streaks in the paper transport direction appeared on solid images until 10,000 horizontal line images were printed, but streaks appeared on solid images after 15,000 to 50,000 prints.

[0280] <Evaluation of density unevenness and solid uniformity in paper transport direction> After leaving the evaluation unit and a toner cartridge filled with evaluation toner in a high-temperature, high-humidity environment of 32.5℃ / 80%RH for more than one day, the evaluation unit was used to print 4000 horizontal line images (letter portrait orientation) in intermittent mode (8-second pause after every two prints). The horizontal line image is an image in which three-dot line images perpendicular to the paper transport direction are placed at 180-dot intervals in the paper transport direction.

[0281] Immediately after the above output was completed, a halftone image (vertical letter, 30H image) and a solid color image (horizontal letter) were output. The 30H image is a halftone image where 256 gradations are represented in hexadecimal, with 00H representing solid white (no image) and FFH representing a solid color image. The output halftone image was visually inspected for density unevenness in the paper transport direction (areas where the density is lighter in a band-like pattern in the paper transport direction). Furthermore, the output solid color image was divided into nine sections (three long and three short), and the image density of the central part of each area was measured using a color reflection densitometer (X-Rite 404A: manufactured by X-Rite). The difference between the maximum and minimum image density values ​​for the nine points was calculated and defined as the maximum density difference. Density unevenness in the paper transport direction and solid color uniformity were evaluated according to the following criteria.

[0282] [Evaluation Criteria for Density Unevenness in Paper Conveyance Direction] A: No density variations occur in the paper transport direction in halftone images. B: One area of ​​density unevenness occurred in the halftone image in the direction of paper transport. C: Two to three areas of density unevenness occurred in the halftone image in the direction of paper transport. D: Four or more areas of density unevenness occurred in the paper transport direction in the halftone image.

[0283] [Evaluation Criteria for Solid Uniformity] A: The maximum density difference in the solid color image is less than 0.04. B: The maximum density difference in the solid image is 0.04 or greater and less than 0.15. C: Maximum density difference in solid color image is 0.15 or greater and less than 0.30. D: Maximum density difference in solid color image is 0.30 or greater.

[0284] [Table 6]

[0285] This disclosure relates to the following configuration.

[0286] (Composition 1) Toner particles containing a binder resin and a release agent, and toner having an external additive on the surface of the toner particles, The external additive contains metal titanate compound fine particles A, silica fine particles B, and inorganic fine particles C. In a time-of-flight secondary ion mass spectrometry measurement using the titanate metal compound fine particles A as a sample, fragment ions corresponding to the structure represented by the following formula (1) were observed. Solid using the titanate metal compound fine particles A as a sample 29 Obtained by Si-NMR CP / MAS method 29 In the Si-NMR spectrum, (i) In the range of -25 ppm to -15 ppm, there is a peak D that is attributed to the D unit structure. (ii) In the range of -60 ppm to -50 ppm, there exists a peak X2 that belongs to the X2 unit structure represented by the following formula (2): (iii) In the range of -70 ppm to -60 ppm, there is a peak X3 that belongs to the X3 unit structure represented by the following formula (3), (iv) The area of ​​the peak D is S D The area of ​​the peak X2 is S X2 The area of ​​the peak X3 is S X3 When S D / (S X2 +S X3 ) is between 0.10 and 1.50, The inorganic fine particles C are fine particles selected from the group consisting of silica fine particles C, alumina fine particles C, and titania fine particles C. Based on the particle size distribution of silica microparticles obtained by combining SEM image analysis and EDX analysis of the toner surface, a graph with the minimum Ferret diameter of primary particles on the horizontal axis and frequency on the vertical axis shows a peak value in the region of minimum Ferret diameter 5 to 100 nm, and peak 1 is observed where the main constituent particles are silica microparticles B. A toner characterized in that, in a graph based on the particle size distribution of the external additive obtained by combining SEM image analysis and EDX analysis of the surface of the toner, with the minimum Ferret diameter of primary particles on the horizontal axis and frequency on the vertical axis, a peak 2 is observed that is on the larger particle size side than the peak value of Peak 1 and in the region of minimum Ferret diameter of 50 to 1000 nm, and the main constituent particles are the inorganic fine particles C.

[0287] [ka]

[0288] (In equation (1), n ​​represents an integer greater than or equal to 2.)

[0289] [ka]

[0290] (In formula (2), R1 represents a hydrocarbon group having 1 to 10 carbon atoms, R2 represents a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, O 1 / 2 (This represents an oxygen atom shared with an adjacent Si or Ti atom.)

[0291] [ka]

[0292] (In formula (3), R1 represents a hydrocarbon group having 1 to 10 carbon atoms, O 1 / 2 (This represents an oxygen atom shared with an adjacent Si or Ti atom.)

[0293] (Configuration 2) Based on the particle size distribution of the metal titanate compound fine particles obtained by combining SEM image analysis and EDX analysis of the surface of the toner, a graph with the minimum Ferret diameter of primary particles on the horizontal axis and frequency on the vertical axis shows a peak value in the region of minimum Ferret diameter 0.5 to 1000 nm, and peak 3 is observed where the main constituent particles are the metal titanate compound fine particles A. The peak value of peak 3 is DA (nm), the peak value of peak 1 is D B (nm), the peak value of peak 2 is D C When (nm), the D A , the D B , the D C The toner described in Configuration 1 satisfies the following relational expression. 0.10≦D A / D B ≤10.00 0.01≦D B / D C ≤0.80 0.01≦D A / D C ≤1.00

[0294] (Composition 3) The coating area ratio (area %) of the metal titanate compound fine particles A relative to the toner particles is S A The coating area ratio (area %) of the silica fine particles B relative to the toner particles is S B The coating area ratio (area %) of the inorganic fine particles C relative to the toner particles is S C When S A、 The S B , the S C The toner described in configuration 1 or 2 satisfies the following relational expression. 0.01≦S A / S B ≤0.30 1.00 ≤ S B / S C ≤80.00 0.30≦S A / S C ≤22.00

[0295] (Composition 4) The aforementioned S X2 and the aforementioned S X3 The toner described in one of the configurations 1 to 3 below satisfies the following relationship. S X2 ≤S X3

[0296] (Composition 5) The toner according to any one of configurations 1 to 4, wherein the titanate metal compound fine particles A are strontium titanate fine particles.

[0297] (Composition 6) The toner according to any one of the configurations 1 to 5, wherein the titanate metal compound fine particles A are fine particles surface-treated with a silane coupling agent and silicone oil.

[0298] (Composition 7) The toner according to configuration 6, wherein the silane coupling agent is an alkyltrialkoxysilane having an alkyl group having 3 to 6 carbon atoms.

[0299] (Composition 8) Based on the particle size distribution of the metal titanate compound fine particles obtained by combining SEM image analysis and EDX analysis of the surface of the toner, a graph with the minimum Ferret diameter of primary particles on the horizontal axis and frequency on the vertical axis shows a peak value in the region of minimum Ferret diameter 0.5 to 1000 nm, and peak 3 is observed where the main constituent particles are the metal titanate compound fine particles A. The peak value of peak 3 is D A When (nm), the D A A toner described in any one of configurations 1 to 7, wherein the wavelength is 5 to 50 nm.

Claims

1. Toner particles containing a binder resin and a release agent, and toner having an external additive on the surface of the toner particles, The external additive contains metal titanate compound fine particles A, silica fine particles B, and inorganic fine particles C. In a time-of-flight secondary ion mass spectrometry measurement using the titanate metal compound fine particles A as a sample, fragment ions corresponding to the structure represented by the following formula (1) were observed. Solid using the titanate metal compound fine particles A as a sample ２９ Obtained by Si-NMR CP / MAS method ２９ In Si-NMR spectra, (i) In the range of -25 ppm to -15 ppm, there is a peak D that is attributed to the D unit structure. (ii) In the range of -60 ppm to -50 ppm, there exists a peak X2 that belongs to the X2 unit structure represented by the following formula (2), (iii) In the range of -70 ppm to -60 ppm, there exists a peak X3 that belongs to the X3 unit structure represented by the following formula (3), (iv) The area of ​​peak D is S Ｄ The area of ​​the peak X2 is S Ｘ２ The area of ​​the peak X3 is S Ｘ３ When this is the case, S Ｄ / ( S Ｘ２ +S Ｘ３ ) is between 0.10 and 1.50, The inorganic fine particles C are fine particles selected from the group consisting of silica fine particles C, alumina fine particles C, and titania fine particles C. Based on the particle size distribution of silica microparticles obtained by combining SEM image analysis and EDX analysis of the toner surface, a graph with the minimum Ferret diameter of primary particles on the horizontal axis and frequency on the vertical axis shows a peak value in the region of minimum Ferret diameter 5 to 100 nm, and peak 1 is observed where the main constituent particles are silica microparticles B. A toner characterized in that, in a graph based on the particle size distribution of the external additive obtained by combining SEM image analysis and EDX analysis of the surface of the toner, with the minimum ferret diameter of primary particles on the horizontal axis and frequency on the vertical axis, a peak 2 is observed that is on the larger particle size side than the peak value of Peak 1 and in the region of minimum ferret diameter of 50 to 1000 nm, and whose main constituent particles are the inorganic fine particles C. 【Chemistry 1】 (In equation (1), n ​​represents an integer greater than or equal to 2.) 【Chemistry 2】 (In formula (2), R1 represents a hydrocarbon group having 1 to 10 carbon atoms, R2 represents a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, and O １／２ represents an oxygen atom shared with an adjacent Si atom or Ti atom.) 【Transformation 3】 (In formula (3), R1 represents a hydrocarbon group having 1 to 10 carbon atoms, O １／２ (This represents an oxygen atom shared with an adjacent Si or Ti atom.)

2. Based on the particle size distribution of the metal titanate compound fine particles obtained by combining SEM image analysis and EDX analysis of the surface of the toner, a graph with the minimum Ferret diameter of primary particles on the horizontal axis and frequency on the vertical axis shows a peak value in the region of minimum Ferret diameter 0.5 to 1000 nm, and peak 3 is observed where the main constituent particles are the metal titanate compound fine particles A. The peak value of peak 3 is D Ａ (nm), the peak value of peak 1 is D Ｂ (nm), the peak value of peak 2 is D Ｃ When (nm), the D Ａ , the D Ｂ , the D Ｃ The toner according to claim 1, wherein the following relational expression is satisfied. 0.10≦D Ａ / D Ｂ ≦10.00 0.01≦D Ｂ / D Ｃ ≦0.80 0.01≦D Ａ / D Ｃ ≦1.00

3. The coating area ratio (area %) of the metal titanate compound fine particles A relative to the toner particles is S Ａ The coating area ratio (area %) of the silica fine particles B relative to the toner particles is S Ｂ The coating area ratio (area %) of the inorganic fine particles C relative to the toner particles is S Ｃ In that case, S Ａ、 The S Ｂ , the S Ｃ The toner according to claim 1 or 2, wherein the following relational expression is satisfied. 0.01≦S Ａ / S Ｂ ≦0.30 1.00≦S Ｂ / S Ｃ ≦80.00 0.30≦S Ａ / S Ｃ ≦22.00

4. The aforementioned S Ｘ２ and the aforementioned S Ｘ３ The toner according to claim 1 or 2, wherein the following relation satisfies the given equation. S Ｘ２ ≦S Ｘ３

5. The toner according to claim 1 or 2, wherein the titanate metal compound fine particles A are strontium titanate fine particles.

6. The toner according to claim 1 or 2, wherein the titanate metal compound fine particles A are fine particles surface-treated with a silane coupling agent and silicone oil.

7. The toner according to claim 6, wherein the silane coupling agent is an alkyltrialkoxysilane having an alkyl group having 3 to 6 carbon atoms.

8. Based on the particle size distribution of the metal titanate compound fine particles obtained by combining SEM image analysis and EDX analysis of the surface of the toner, a graph with the minimum Ferret diameter of primary particles on the horizontal axis and frequency on the vertical axis shows a peak value in the region of minimum Ferret diameter 0.5 to 1000 nm, and peak 3 is observed where the main constituent particles are the metal titanate compound fine particles A. The peak value of peak 3 is D Ａ When (nm), the D Ａ The toner according to claim 1 or 2, wherein the wavelength is 5 to 50 nm.

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