toner

Abstract

To provide a toner that has reduced the occurrence of drop-off and streaks even after a long-term printing in a high temperature and high humidity environment.SOLUTION: A toner contains a toner particle containing a polyester resin and silica fine particles. In measurement in time-of-flight secondary ion mass spectroscopy of the silica fine particles, fragment ions corresponding to the D-unit structure are observed. When the silica fine particles are dispersed in a mixed solution of ethanol and a NaCl solution and a titration operation using sodium hydroxide is performed, a titration amount falls within a specific range. In solid 29Si-NMR measurement of the silica fine particles, when the area of a peak where a peak top is present within a range from -25 to -15 ppm is defined as D, and the area of a peak where a peak top is present within a range exceeding -19 ppm and -17 ppm or less is defined as D1, the specific surface area of the silica fine particles, D, and D1 are present in a specific relationship. The polyester resin is present on the surface of the toner particle.SELECTED DRAWING: None

Description

[Technical Field]

[0001] This disclosure relates to toner used in image forming methods such as electrophotography. [Background technology]

[0002] In recent years, efforts have been made to extend the lifespan and improve the environmental stability of copiers and printers. Toner cartridges are now required to have stress resistance to withstand friction within the cartridge during long-term printing, as well as static charge stability that prevents static charge loss even in high-temperature and high-humidity environments.

[0003] To date, in order to improve stress resistance, for example, Patent Document 1 has investigated methods of incorporating polyester resin into toner particles. Furthermore, with the aim of improving environmental stability, for example, Patent Document 2 describes a method of externally adding silica particles whose surfaces have been hydrophobized with cyclic siloxane or dimethyl silicone oil to toner particles. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2000-147831 [Patent Document 2] Japanese Patent Publication No. 2016-167029 [Overview of the project] [Problems that the invention aims to solve]

[0005] The toner described in Patent Document 1 improves stress resistance. However, polyester resin easily absorbs moisture in high-temperature, high-humidity environments, which tends to reduce the charge of the toner. As a result, it has been found that downstream of the toner regulating section of the developing roller, the toner is not retained by the developing roller and is printed on non-printable areas, a type of image defect known as "toner blotting." Furthermore, while the toner described in Patent Document 2 shows some effect on initial environmental stability, the surface treatment of the silica nanoparticles tends to deteriorate after prolonged printing, making it difficult to achieve stable electrostatic properties. For the reasons stated above, there is a need for the development of toners with superior stress resistance and environmental stability. This disclosure provides a toner that exhibits minimal blotting and streaking even after prolonged printing in high-temperature and high-humidity environments. [Means for solving the problem]

[0006] This disclosure relates to a toner containing polyester resin toner particles and silica fine particles on the surface of said toner particles, In time-of-flight secondary ion mass spectrometry measurements of the silica nanoparticles, fragment ions corresponding to the structure shown in equation (1) below were observed. [ka] In equation (1), n ​​represents an integer of 1 or greater, When 2.00 g of the silica fine particles were dispersed in a mixture of 25.0 g of ethanol and 75.0 g of a 20% by mass NaCl aqueous solution and titrated using sodium hydroxide, Sn, defined as Sn = {(ab) × c × NA} / (d × e), satisfies equation (2) below. 0.05 ≤ Sn ≤ 0.20 ···(2) In formula (2), a is the amount of NaOH titration (L) required to adjust the mixture containing the dispersed silica particles to pH 9.0. b is the amount of NaOH titration (L) required to adjust a mixture of 25.0 g of ethanol and 75.0 g of 20% by mass NaCl aqueous solution to pH 9.0. c is the concentration (mol / L) of the NaOH solution used in the titration. NA is Avogadro's number, d is the mass (g) of the silica fine particles, e is the BET specific surface area (nm) of the silica nanoparticles. 2 / g) Solid silica fine particles 29 In the chemical shift obtained by the Si-NMR DD / MAS method, D is the area of ​​the peaks with peak tops in the range of -25 to -15 ppm, S is the sum of the areas of the M, D, T, and Q unit peaks in the range of -140 to 100 ppm, and B is the specific surface area of ​​the silica nanoparticles. 2 When we set it to / g, The ratio of (D / S) to B, (D / S) / B, is 5.7 × 10 -4 ~4.9×10 -3 And, The (D / S) / B value measured after washing the silica microparticles with chloroform was 1.7 × 10⁻⁶. -4 ~4.9×10 -3 And, In the chemical shift, when D1 is defined as the area of ​​the peaks where the peak top is located in the range between -19 ppm and -17 ppm, the ratio of D1 to D (D1 / D) is between 0.09 and 0.32. This invention relates to a toner in which the polyester resin is present on the surface of the toner particles. [Effects of the Invention]

[0007] This disclosure makes it possible to provide toner that exhibits minimal blotting and streaking even after prolonged printing in high-temperature and high-humidity environments. [Modes for carrying out the invention]

[0008] In this disclosure, descriptions indicating numerical ranges such as "XX or more and YY or less" or "XX to YY" mean a numerical range that includes the lower and upper limits, unless otherwise specified. When numerical ranges are described in steps, the upper and lower limits of each numerical range can be combined in any way. Furthermore, a monomer unit refers to the reacted form of monomer substances in a polymer.

[0009] The inventors believe the above toner can solve the problem as follows: To improve durability, the toner particles must contain polyester resin, and the polyester resin must be present on the surface of the toner particles. This improves the elasticity of the toner, suppressing the occurrence of streaks even during long-term printing.

[0010] Furthermore, in time-of-flight secondary ion mass spectrometry (TOF-SIMS) measurements of silica nanoparticles, it is necessary to observe fragment ions corresponding to the structure shown in equation (1). The observation of fragment ions shown in equation (1) indicates that the silica nanoparticles have been surface-treated with a surface treatment agent having a polydimethylsiloxane structure. Polydimethylsiloxane is hydrophobic, and surface treatment with a treatment agent having a polydimethylsiloxane structure can prevent moisture adsorption onto toner in high-temperature, high-humidity environments of silica nanoparticles. [ka]

[0011] (In formula (1), n ​​is an integer of 1 or greater (preferably between 1 and 500, more preferably between 1 and 200, even more preferably between 1 and 100, and even more preferably between 1 and 80).) TOF-SIMS is a method for analyzing the surface composition of a sample 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 silica nanoparticles. The mass spectrum of secondary ions obtained by the measurement is a fragment ion that reflects the molecular structure of the surface treatment agent of the silica nanoparticles. In TOF-SIMS measurements, fragment ions corresponding to the structure shown in formula (1) are observed in silica nanoparticles. In this disclosure, structural units having this structure are defined as D units. When D unit fragment ions are observed by TOF-SIMS, it means that the silica nanoparticles have been surface-treated with a surface treatment agent containing D units.

[0012] In addition, it is necessary to control the amount of Si-OR groups (where R is a methyl group, an ethyl group, or a hydrogen atom) in the silica fine particles. The amount of Si-OR groups is the sum of the amount of Si-OR groups on the surface of the silica fine particle substrate (the silica fine particles before surface treatment) and the amount of Si-OR groups in the surface treatment agent of the silica fine particles. The Si-OR groups are polarized, and Si―O δ- ―R δ+ has polarity like this, so it is considered that the chargeability is controlled by the content. If the amount of Si-OR is small, chargeability cannot be obtained. If the amount of Si-OR is excessive, the chargeability is likely to decrease in a high-temperature and high-humidity environment. Among the Si-OR groups, the Si-OH groups on the surface of the silica fine particle substrate are likely to adsorb moisture, so it is considered that they have a particularly large influence on the chargeability. The amount of Si-OH groups can be evaluated by the value Sn (number / nm 2 ) obtained from the titration amount of sodium hydroxide. This is because the Si-OH groups of the silica fine particle substrate and the Si-OH groups of polydimethylsiloxane undergo a neutralization reaction with sodium hydroxide.

[0013] Specifically, when 2.00 g of silica fine particles are dispersed in a mixed solution of 25.0 g of ethanol and 75.0 g of a 20% by mass NaCl aqueous solution and a titration operation is performed using sodium hydroxide, it is necessary that Sn defined by Sn = {(a - b) × c × NA} / (d × e) satisfies the following formula (2). 0.05 ≦ Sn ≦ 0.20 ···(2) In the formula (2), a is the titration amount (L) of NaOH required to adjust the above mixed solution in which the silica fine particles are dispersed to pH 9.0, b is the titration amount (L) of NaOH required to adjust the mixed solution of 25.0 g of ethanol and 75.0 g of a 20% by mass NaCl aqueous solution to pH 9.0, c is the concentration (mol / L) of the NaOH solution used for titration, NA is Avogadro's number, d is the mass (g) of the silica fine particles, e is the BET specific surface area (nm 2 / g) of the silica fine particles.

[0014] As mentioned above, if Sn is less than 0.05, there are too few Si-OH groups, which are charging sites, resulting in reduced chargeability, and if Sn is greater than 0.20, it prevents moisture adsorption in high temperature and high humidity environments. This is not possible. Sn is preferably 0.08 to 0.19, and more preferably 0.10 to 0.18. The amount of Sn can be reduced by increasing the reaction time during the surface treatment of the silica nanoparticle substrate. Conversely, the amount of Sn can be increased by shortening the reaction time during the surface treatment of the silica nanoparticle substrate.

[0015] As mentioned above, among the Si-OR groups, the Si-OH groups on the surface of the silica nanoparticle substrate readily adsorb moisture and have a significant impact on electrostatic properties. In contrast, the Si-OH groups in the surface treatment agent for silica nanoparticles exist at a distance from the silica nanoparticle substrate, such as through the structure shown in formula (1) above or via the D2 units described later. Furthermore, because two highly hydrophobic methyl groups are bonded to Si, the effect of moisture adsorption is considered to be small.

[0016] Furthermore, to control the Si-OR group, it is necessary to control the surface treatment state of the silica nanoparticles ((D / S) / B, D1 / D). The surface treatment state of the silica nanoparticles is solid. 29 Si-NMR It is calculated using the DD / MAS method. In the DD / MAS measurement method, all Si atoms in the sample are observed, so quantitative information about the chemical bonding state of Si atoms in silica nanoparticles can be obtained.

[0017] Generally, solid 29 Si-NMR allows observation of four types of peaks for Si atoms in a solid sample: M-unit (Equation (4)), D-unit (Equation (5)), T-unit (Equation (6)), and Q-unit (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) R in equations (4), (5), and (6) i , R j , R k , R g , R h , R m This refers to alkyl groups such as hydrocarbon groups having 1 to 6 carbon atoms, halogen atoms, hydroxyl groups, acetoxy groups, or alkoxy groups that are bonded to silicon.

[0018] When silica nanoparticles are measured using DD / MAS, the Q unit indicates a peak corresponding to the Si atoms in the silica nanoparticle substrate before surface treatment. In this disclosure, when silica nanoparticles are surface-treated with a surface treatment agent such as silicone oil, the portion derived from the surface treatment agent is also referred to as silica nanoparticles. Furthermore, silica nanoparticles before surface treatment are also referred to as the silica nanoparticle substrate. The BET specific surface area of ​​the silica nanoparticles after surface treatment is given by B(m²). 2 Let it be / g). The M, D, and T units represent peaks corresponding to the structure of the surface treatment agent for silica fine particles, as shown in formulas (4) to (6) above. All are solids 29 Identification is possible by the chemical shift values ​​of the Si-NMR spectrum. Q units appear in the chemical shift range of -130 to -85 ppm, T units in the range of -65 to -51 ppm, D units in the range of -25 to -15 ppm, and M units in the range of 10 to 25 ppm, and each can be quantified by its integral value. The respective peak integral values ​​are denoted as Q, T, D, and M, and the sum of these integral values ​​is denoted as S.

[0019] Solid silica nanoparticles 29 In the chemical shift obtained by the Si-NMR DD / MAS method, D is the area of ​​the peaks with peak tops in the range of -25 to -15 ppm, and S is the sum of the areas of the M, D, T, and Q unit peaks in the range of -140 to 100 ppm. The BET specific surface area of ​​the silica nanoparticles is B(m²).2 Let (D / S) / B be 5.7 × 10 -4 ~4.9×10 -3 That is the case.

[0020] The parameter (D / S) / B represents the amount of Si atoms per unit surface area that constitutes the D unit relative to the total Si atomic amount of the silica nanoparticles. Here, in TOF-SIMS, The fragment shown by formula (1) is observed, and the solid 29 In Si-NMR measurements, silica nanoparticles exhibiting peaks in the D unit indicate that they have been surface-treated with a compound containing a dimethylsiloxane structure. In other words, the parameter (D / S) / B represents the amount of dimethylsiloxane on the surface of silica nanoparticles per unit surface area. A smaller (D / S) / B value indicates less dimethylsiloxane on the surface of the silica nanoparticles, meaning it does not inhibit fluidity as an external additive. However, silanol groups tend to remain on the surface of the silica nanoparticle substrate, making it prone to static charge reduction due to moisture in high-temperature, high-humidity environments.

[0021] Conversely, a larger (D / S) / B ratio results in a greater amount of dimethylsiloxane on the surface of the silica nanoparticles. However, an excess of D units inhibits fluidity as an external additive, which also tends to reduce electrostatic properties. Furthermore, if the dimethylsiloxane treatment is uneven, silanol groups remain on the surface of the silica nanoparticle substrate, which can lead to reduced electrostatic properties, especially in high-temperature and high-humidity environments when printing a large number of sheets. Therefore, (D / S) / B is 5.7 × 10 -4 ~4.9×10 -3 It is necessary that (D / S) / B is 5.7 × 10 -4 If it is less than 4.9 × 10, it cannot prevent moisture adsorption in a high-temperature, high-humidity environment. -3 If the value is too large, the toner's fluidity decreases and its chargeability decreases. (D / S) / B is preferably 6.1 × 10 -4 ~3.7×10 -3 And more preferably 7.5 × 10 -4 ~3.3×10 -3 That is the case.

[0022] (D / S) / B can be increased by increasing the amount of surface treatment agent used when treating the silica nanoparticle substrate, or by using a surface treatment agent that contains a large amount of components having a polydimethylsiloxane structure. On the other hand, (D / S) / B can be decreased by decreasing the amount of surface treatment agent used when treating the silica nanoparticle substrate, or by using a surface treatment agent that does not contain a large amount of components having a polydimethylsiloxane structure.

[0023] Furthermore, the (D / S) / B measured after washing the silica microparticles with chloroform was 1.7 × 10⁻⁶. -4 ~4.9×10 -3 This is necessary. The cleaning operation removes the surface treatment agent that has been physically adsorbed, leaving behind the chemically bonded surface treatment agent. Therefore, (D / S) / B after cleaning indicates the amount of chemically bonded D units. (D / S) / B is 1.7 × 10 -4 If it is less than 4.9 × 10, it cannot prevent moisture adsorption in high temperature and high humidity environments. -3 If the size is too large, the toner's fluidity decreases and its chargeability declines. The (D / S) / B ratio after washing silica microparticles with chloroform is preferably 2.5 × 10⁻⁶. -4 ~3.7×10 -3 And more preferably 3.5 × 10 -4 ~3.3×10 -3 That is the case.

[0024] Also, solid silica nanoparticles 29 In the chemical shift obtained by the Si-NMR DD / MAS method, D1 is defined as the area of ​​the peak whose peak top is in the range between -19 ppm and -17 ppm. In silica nanoparticles treated with D units, D1 represents the Si-OR group at the end of the D unit (more specifically, -Si(R2)-OR; R is a methyl group, an ethyl group, or a hydrogen atom, respectively). The highly hydrophobic D1 at the end of the D unit becomes polarized, causing the oxygen atom in the Si-OR group to acquire a negative charge δ-.

[0025] Therefore, the ends of structures derived from surface treatment agents containing such D1 are highly electron-donating, and have the effect of imparting electrostatic properties to hydrophobic group ends. Furthermore, as mentioned above, the Si-OH group of D1 at the end of the D unit has moderately high hydrophobicity compared to polar groups such as silanol groups in the Q unit present on the surface of the silica nanoparticle substrate. In addition, as expressed by (D / S) / B after washing with chloroform, the D unit is bound to the silica nanoparticle substrate to a certain extent, and the D1 at the end of the D unit is located away from the surface of the silica nanoparticle substrate. Therefore, the Si-OH group of D1 is less likely to reduce electrostatic properties and less likely to be affected by moisture in the silica nanoparticle substrate compared to the silanol groups present on the surface of the silica nanoparticle substrate.

[0026] Therefore, the surface of the silica nanoparticles is treated with a treatment agent containing D units to reduce the silanol groups on the surface of the silica nanoparticle substrate and introduce D1 at the D unit terminus, thereby adjusting (D / S) / B, and (D / S) / B and D1 / D after washing with chloroform to an appropriate range. By satisfying these conditions, the amount of charge can be improved even in high temperature and high humidity environments. Furthermore, the presence of D1 enhances the adhesion between the toner particles and the silica nanoparticles through dipole interaction with the ester portion of the polyester resin present on the toner particle surface. This further prevents moisture adsorption in high temperature and high humidity environments.

[0027] The ratio of D1 to D (D1 / D) must be between 0.09 and 0.32. If D1 is less than 0.09, the electrostatic properties of D1 cannot be exhibited, and if it is greater than 0.32, moisture adsorption in high-temperature, high-humidity environments cannot be prevented. D1 / D is preferably between 0.10 and 0.30, and more preferably between 0.15 and 0.25. The D1 / D ratio can be increased by increasing the content ratio of silanols and cyclic siloxanes in the treatment agent components used for surface treatment of silica microparticle substrates, or by lowering the treatment temperature. On the other hand, the D1 / D ratio can be decreased by lowering the content ratio of silanols and cyclic siloxanes in the treatment agent components used for surface treatment of silica microparticle substrates, or by increasing the treatment temperature.

[0028] Also, solid 29 In the chemical shift obtained by the Si-NMR DD / MAS method, D2 is defined as the area of ​​the peak whose peak top is in the range of -23 to -19 ppm. Among the D units measured in silica nanoparticles, it is known that the Si atoms bonded to the OR group at the end of the D unit correspond to peak D1. It is also known that the Si atoms within the dimethylsiloxane chain correspond to peak D2.

[0029] Furthermore, the ratio of D1 to D2 (D1 / D2) is preferably 0.15 to 0.42, more preferably 0.18 to 0.40, and even more preferably 0.30 to 0.39. When D1 / D2 is 0.15 or higher, the effect of exhibiting the electrostatic properties of D1 is enhanced, and when it is 0.42 or lower, the environmental stability in high-temperature and high-humidity environments is further improved. The D1 / D2 ratio can be increased by increasing the content ratio of silanols and cyclic siloxanes in the treatment agent components used for surface treatment of silica microparticle substrates. On the other hand, the D1 / D2 ratio can be decreased by decreasing the content ratio of silanols and cyclic siloxanes in the treatment agent components used for surface treatment of silica microparticle substrates.

[0030] Furthermore, the ratio of D2 to D (D2 / D) is preferably 0.30 to 0.90, more preferably 0.40 to 0.70, and even more preferably 0.45 to 0.60. A D2 / D of 0.30 or higher improves the electrostatic stability in high-temperature and high-humidity environments, while a D2 / D of 0.90 or lower improves fluidity and allows for higher electrostatic properties.

[0031] When Sp (area %) represents the percentage of polyester resin present on the surface of toner particles, Sp is preferably 50 area % or more. More preferably 60 area % or more, and even more preferably 70 area % or more. Having Sp of 50 area % or more can further improve durability during long-term printing. There is no particular upper limit to Sp, but it is preferably 100 area % or less, more preferably 98 area % or less, and even more preferably 95 area % or less. Sp can be controlled by the acid value of the polyester resin. Polyesters with a higher acid value are more hydrophilic and tend to exist on the toner surface, while polyesters with a lower acid value are more hydrophobic and tend to exist inside the toner.

[0032] Furthermore, the coverage rate (Ssi) of silica fine particles on the surface of toner particles, calculated from scanning electron microscope (SEM) images of the toner surface, is more preferably 30 area percent or more. More preferably 50 to 90 area percent, and even more preferably 60 to 85 area percent. Having an Ssi coverage rate of 30 area percent or more improves the electrostatic stability in high-temperature and high-humidity environments. Ssi can be controlled by the amount of silica nanoparticles added.

[0033] Furthermore, the ratio of the polyester resin content (Sp) to the silica fine particle coverage (Ssi) (Sp / Ssi) is preferably 0.70 to 2.50. More preferably, it is 0.40 to 2.00, and even more preferably, 0.50 to 1.50. An Sp / Ssi of 0.7 or higher can further improve durability during long-term printing, and an Sp / Ssi of 2.5 or lower can further improve electrostatic stability in high-temperature and high-humidity environments.

[0034] Furthermore, the silica fine particle content is preferably 0.3 to 2.0 parts by mass, more preferably 0.18 to 0.40 parts by mass, and even more preferably 0.30 to 0.39 parts by mass per 100 parts by mass of toner particles. A content of 0.3 parts by mass or more allows for higher electrostatic properties even during long-term printing, while a content of 2.0 parts by mass or less suppresses the detachment of excess silica fine particles from the toner, thereby improving electrostatic stability.

[0035] Furthermore, the number-average particle size of the primary particles of the silica nanoparticles is preferably 5 to 50 nm, more preferably 10 to 40 nm, and even more preferably 15 to 25 nm. A number-average particle size of 5 nm or more makes it easier to prevent moisture adsorption to the toner particles, thus improving the charge stability in high-temperature and high-humidity environments. A number-average particle size of 50 nm or less increases the surface area of ​​the silica nanoparticles, allowing for higher charge levels.

[0036] The silica microparticles preferably contain both small-particle and large-particle silica microparticles. The number-average particle size of the primary particles of the small-particle silica microparticles is preferably 5 to 25 nm, and more preferably 10 to 20 nm. The number-average particle size of the primary particles of the large-particle silica microparticles is preferably greater than 25 nm and 50 nm or less, and more preferably 30 to 40 nm. The BET specific surface area of ​​small-particle silica nanoparticles is 100-500 m². 2 It is preferable that the amount be / g, and 150-300m 2 It is more preferable that the amount is / g. Also, the BET specific surface area of ​​large-particle silica fine particles is 10 to 100 m². 2 It is preferable that the amount be / g, and 30-80m 2 It is more preferable that it be / g. The mass-based content ratio of small-particle silica particles to large-particle silica particles is preferably 20:1 to 5:1, and more preferably 15:1 to 7:1. Furthermore, the BET specific surface area B of the silica nanoparticles after surface treatment is 40-200 m². 2 It is preferable that the amount be / g, and 100-150m 2 It is more preferable that it be / g.

[0037] Furthermore, it is more preferable that the silica nanoparticles are surface-treated with at least the compound represented by formula (3) below. [ka]

[0038] In equation (3), R 1 , R 2 Each of these is independently a carbinol group, a hydroxyl group, an epoxy group, a carboxyl group, an alkyl group (preferably having 1 to 6 carbon atoms, more preferably 1 to 3 carbon atoms), or a hydrogen atom. m is the average number of repeating units and is an integer from 1 to 200 (preferably 30 to 150, more preferably 70 to 130).

[0039] The surface treatment agent of formula (3) can further improve the electrostatic stability in high-temperature and high-humidity environments. The surface treatment agent used is not particularly limited as long as it is a compound represented by formula (3), and known compounds can be used. These may be used alone or in combination of two or more. In addition, two or more surface treatment agents with different functional groups may be used sequentially or in mixture, or two or more surface treatment agents having the same functional group but different viscosity and molecular weight distribution may be used sequentially or in mixture.

[0040] In particular, the silica fine particles are preferably hydrophobized silica particles obtained by heat-treating a silica fine particle substrate with a cyclic siloxane, and then heat-treating it with silicone oil. When the amount of cyclic siloxane treated per 100 parts by mass of silica fine particles is X parts by mass and the amount of silicone oil treated is Y parts by mass, the ratio of X to Y (X / Y) is preferably 0.60 to 1.20. More preferably it is 0.65 to 1.15, and even more preferably 0.70 to 1.00. A X / Y ratio of 0.60 or higher allows for higher toner charging due to D1 derived from cyclic siloxanes, while an X / Y ratio of 1.20 or lower improves charging stability in high-temperature, high-humidity environments.

[0041] When the acid value of the polyester resin is expressed as Av (mgKOH / g), Av is preferably 2.0 to 30.0. Av is more preferably 2.5 to 15.0, and even more preferably 4.0 to 10.0. Furthermore, it is preferable that the value of (Av / Sp) / Sn calculated from Sp, Av, and Sn is between 0.20 and 7.00. More preferably, (Av / Sp) / Sn is between 0.40 and 2.00, and even more preferably between 0.70 and 0.80. When Av is 2.0 or higher and (Av / Sp) / Sn is 0.20 or higher, the adhesion between the polyester resin and silica nanoparticles due to dipole interaction is further enhanced. When Av is 30.0 or lower and (Av / Sp) / Sn is 7.00 or lower, the charge stability in high-temperature and high-humidity environments can be further improved.

[0042] The silica microparticle substrate that serves as the base material before surface treatment with silicone oil or the like can be any silica microparticle obtained by known methods without any particular limitations. For example, fumed silica, wet-process silica, and sol-gel silica are typical examples. Furthermore, these silica particles may be partially or entirely molten silica.

[0043] For the silica microparticle substrate, it is possible to appropriately select and use one from among fumed silica, wet silica, etc., according to the required characteristics of the individual toner. In particular, fumed silica has excellent fluidity-imparting effects and is used as an external additive for electrophotographic toners. It is suitable as a sub-substrate.

[0044] Silica nanoparticles are used in which the silica nanoparticle substrate has been surface-treated to impart hydrophobicity and fluidity. Surface treatment methods include chemical treatment with silicon compounds that react with or physically adsorb to the silica nanoparticle substrate. The method for surface treatment of the silica microparticle substrate is not particularly limited and can be performed by bringing a surface treatment agent containing siloxane bonds into contact with the silica microparticles. From the viewpoint of uniformly treating the surface of the silica microparticle substrate and easily achieving the above physical properties, it is preferable to bring the surface treatment agent into contact with the silica microparticle substrate in a dry manner. As will be described later, examples include bringing the vapor of the surface treatment agent into contact with the silica microparticle raw material, or spraying the undiluted solution of the surface treatment agent or a diluted solution with various solvents into contact with the silica microparticle substrate.

[0045] As a surface treatment method for a silica microparticle substrate, the method for producing silica microparticles preferably comprises a first step of surface treatment (dry treatment) of the silica microparticle substrate with a cyclic siloxane, and a second step of surface treatment (dry treatment) of the silica microparticle substrate after cyclic siloxane treatment with silicone oil. The silica microparticles are preferably the silicone oil-treated product of the silica microparticles treated with cyclic siloxane. The method for producing toner preferably includes a step of preparing silica microparticles obtained by the above method.

[0046] Regarding the first treatment, high-temperature treatment with a low molecular weight cyclic siloxane can efficiently reduce the silanol groups on the surface of the silica nanoparticle substrate, and short dimethylsiloxane chains with OH groups at their ends can be added to the surface of the silica nanoparticle substrate. The treatment temperature for cyclic siloxane on the surface of the silica nanoparticle substrate is preferably 300°C or higher. A temperature of 300°C or higher effectively reduces the silanol groups on the surface of the silica nanoparticle substrate. Furthermore, a treatment temperature of 300°C or higher allows for the formation and cleavage of siloxane bonds, enabling more uniform treatment of the silica nanoparticle substrate surface while uniformly controlling the siloxane chain length. The treatment temperature for the cyclic siloxane on the silica nanoparticle substrate surface is more preferably 310°C or higher, even more preferably 320°C or higher, and even more preferably 330°C or higher. There is no particular upper limit, but it is preferably 380°C or lower, and more preferably 350°C or lower.

[0047] After the above cyclic siloxane treatment, the silica nanoparticle substrate treated with the cyclic siloxane is heat-treated with silicone oil as a second treatment. The silicone oil binds to the terminal OH groups of the components reacted with the cyclic siloxane in the first treatment, allowing the long-chain dimethylsiloxane component to be introduced to the surface of the silica nanoparticles. The temperature during the silicone oil treatment of the silica nanoparticle substrate surface is preferably 300°C or higher, more preferably 320°C or higher, and even more preferably 330°C or higher. There is no particular upper limit, but it is preferably 380°C or lower, and more preferably 350°C or lower. By controlling the processing amount X of the cyclic siloxane and the processing amount Y of the silicone oil mentioned above, the silanol component on the surface of the silica microparticle substrate can be reduced, and the amounts of D units and D1 mentioned above can be controlled. This allows for improved electrostatic stability without reducing the fluidity of the toner with a small amount of surface treatment.

[0048] As the cyclic siloxane, at least one can be selected from the group consisting of low molecular weight cyclic siloxanes with up to 10 membered rings, such as hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, and decamethylcyclopentasiloxane. Among these, octamethylcyclotetrasiloxane is preferred. Furthermore, silicone oil refers to an oily substance having a molecular structure with siloxane bonds as its main chain, and any silicone oil that satisfies formula (3) above can be used without any particular restrictions as long as it is generally available. Specifically, examples include silicone oils consisting of a linear polysiloxane skeleton, such as dimethyl silicone oil, alkyl-modified silicone oil, olefin-modified silicone oil, fatty acid-modified silicone oil, alkoxy-modified silicone oil, polyether-modified silicone oil, and carbinol-modified silicone oil.

[0049] The processing time in the first and second processes varies depending on the processing temperature and the reactivity of the surface treatment agent used, but is preferably 5 minutes to 300 minutes, more preferably 30 minutes to 240 minutes, and even more preferably 50 minutes to 200 minutes. The above-mentioned processing temperature and processing time for the surface treatment are preferable from the viewpoint of allowing the treatment agent to react sufficiently with the silica fine particle substrate, and from the viewpoint of production efficiency.

[0050] In the first treatment, contact of the surface treatment agent with the silica microparticle substrate is preferably carried out by contacting the vapor of the surface treatment agent under reduced pressure or in an inert gas atmosphere such as a nitrogen atmosphere. By using the vapor contact method, it is possible to easily remove surface treatment agents that do not react with the silica microparticle surface and to appropriately coat the surface of the silica microparticles with modifying groups having appropriate polarity. When using the vapor contact method, it is preferable to perform the treatment at a treatment temperature above the boiling point of the surface treatment agent. The vapor contact may be carried out in multiple stages. When contacting a surface treatment agent vapor under an inert gas atmosphere such as a nitrogen atmosphere, it is preferable that the pressure (gauge pressure) due to the surface treatment agent vapor in the container be 50 to 300 kPa or less, and more preferably 150 to 250 kPa.

[0051] The toner particles may contain a binder resin. Examples of binder resins include vinyl resins and polyester resins, but there are no particular limitations, and any known resin can be used. Preferably, the toner particles contain a polyester resin as the binder resin. Specifically, styrene copolymers such as polystyrene, styrene-propylene copolymer, styrene-vinyltoluene copolymer, styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer, styrene-butyl acrylate copolymer, styrene-octyl acrylate copolymer, styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate copolymer, styrene-octyl methacrylate copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-maleic acid copolymer, and styrene-maleic acid ester copolymer, as well as polyacrylic acid esters, polymethacrylate esters, and polyvinyl acetate can be used, and these can be used individually or in combination. Among these, styrene copolymers and polyester resins are particularly preferred in terms of developing characteristics and fixing properties. Polyester resins are more preferred.

[0052] The components that make up polyester resin are described in detail. Note that depending on the type and application, one or more of the following components may be used. Examples of divalent carboxylic acid components constituting polyester resins include the following dicarboxylic acids or their derivatives: benzenedicarboxylic acids such as phthalic acid, terephthalic acid, isophthalic acid, and phthalic anhydride, or their anhydrides or lower alkyl esters; alkyldicarboxylic acids such as succinic acid, adipic acid, sebacic acid, and azelaic acid, or their anhydrides or lower alkyl esters; alkenyl succinic acids or alkyl succinic acids with an average number of carbon atoms of 1 to 50, or their anhydrides or lower alkyl esters; and unsaturated dicarboxylic acids such as fumaric acid, maleic acid, citraconic acid, and itaconic acid, or their anhydrides or lower alkyl esters. Examples of alkyl groups in the lower alkyl ester include methyl, ethyl, propyl, and isopropyl groups.

[0053] On the other hand, the following are examples of divalent alcohol components that make up polyester resin. It is possible. Ethylene glycol, polyethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, diethylene glycol, triethylene glycol, 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, 2-methyl-1,3-propanediol, 2-ethyl-1,3-hexanediol, 1,4-cyclohexanedimethanol (CHDM), hydrogenated bisphenol A, bisphenols represented by formula (I-1) and their derivatives: and diols represented by formula (I-2). [ka]

[0054] In equation (I-1), R is an ethylene group or a propylene group, x and y are integers greater than or equal to 0, and the average value of x + y is between 0 and 10. [ka]

[0055] In equation (I-2), R' is an ethylene group or a propylene group, x' and y' are integers greater than or equal to 0, and the average value of x'+y' is between 0 and 10.

[0056] In addition to the divalent carboxylic acid component and divalent alcohol component described above, the components of the polyester resin may also contain trivalent or higher carboxylic acid components and trivalent or higher alcohol components. There are no particular limitations on the trivalent or higher carboxylic acid components, but examples include trimellitic acid, trimellitic anhydride, and pyromellitic acid. Examples of trivalent or higher alcohol components include trimethylolpropane, pentaerythritol, and glycerin.

[0057] In addition to the compounds mentioned above, the polyester resin may also contain monovalent carboxylic acid components and monovalent alcohol components. Specifically, examples of monovalent carboxylic acid components include palmitic acid, stearic acid, arachidic acid, behenic acid, cerotic acid, heptacosanoic acid, montanic acid, melissic acid, laxeric acid, tetracontanoic acid, and pentacontanoic acid. Other examples of monohydric alcohol components include behenyl alcohol, ceryl alcohol, melicyl alcohol, and tetracontanol.

[0058] A charge control agent may be added to the toner particles. Effective charge control agents for negative charging include organometallic complex compounds and chelate compounds, such as monoazo metal complex compounds, acetylacetone metal complex compounds, and metal complex compounds of aromatic hydroxycarboxylic acids or aromatic dicarboxylic acids. Examples of commercially available products include Spilon Black TRH, T-77, T-95 (Hodogaya Chemical Co., Ltd.), and BONTRON® S-34, S-44, S-54, E-84, E-88, E-89 (Orient Chemical Co., Ltd.).

[0059] Furthermore, as positively charged charge control agents, modified products such as nigrosine and fatty acid metal salts; quaternary ammonium salts such as tributylbenzylammonium-1-hydroxy-4-naphthosulfonate and tetrabutylammonium tetrafluoroborate, and similar compounds. Examples include onium salts such as phosphonium salts, which are analogous to these, and lake pigments thereof; triphenylmethane dyes and lake pigments thereof (lake agents include phosphotungstic acid, phosphomolybdenic acid, phosphotungstenmolybdenic acid, tannic acid, lauric acid, gallic acid, ferricyanic acid, ferrocyanic acid, ferrocyanic compounds, etc.); metal salts of higher fatty acids; diorganostin oxides such as dibutyltin oxide, dioctyltin oxide, and dicyclohexyltin oxide; and organostin borates such as dibutyltin borate, dioctyltin borate, and dicyclohexyltin borate. Specific examples of commercially available products include TP-302, TP-415 (Hodogaya Chemical Co., Ltd.), BONTRON® N-01, N-04, N-07, P-51 (Orient Chemical Co., Ltd.), and Copy Blue PR (Clariant Co., Ltd.).

[0060] These charge control agents can be used individually or in combination of two or more. From the viewpoint of the toner's charge level, the amount of these charge control agents used is preferably 0.1 to 10.0 parts by mass per 100 parts by mass of binder resin, and more preferably 0.1 to 5.0 parts by mass.

[0061] A release agent may be added to the toner particles as needed to improve adhesion. The release agent is not particularly limited, and known release agents can be used. 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. Furthermore, as ester waxes, monofunctional ester waxes, difunctional ester waxes, and polyfunctional ester waxes such as tetrafunctional and hexafunctional waxes can be used.

[0062] Toner particles may contain a colorant. Examples of colorants include organic pigments, organic dyes, and inorganic pigments, but are not particularly limited and any known colorant can be used. Examples of cyanide-based colorants include copper phthalocyanine compounds and their derivatives, anthraquinone compounds, and basic dye lake compounds. Specifically, these include: CI Pigment Blue 1, 7, 15, 15:1, 15:2, 15:3, 15:4, 60, 62, and 66.

[0063] Examples of magenta-based colorants include: condensed azo compounds, diketopyrrolopyrrole compounds, anthraquinone compounds, quinacridone compounds, basic dye lake compounds, naphthol compounds, benzimidazolon compounds, thioindigo compounds, and perylene compounds. Specifically, these include the following: 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.

[0064] Examples of yellow colorants include condensed azo compounds, isoindolinone compounds, anthraquinone compounds, azo metal complexes, methine compounds, and allylamide compounds. Specifically, the following are examples: 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.

[0065] Examples of black colorants include carbon black, as well as those colored black using the aforementioned yellow colorants, magenta colorants, cyan colorants, and magnetic materials. These colorants can be used individually, in combination, or in solid solution form. The colorants used in the present invention are selected based on their hue angle, saturation, brightness, lightfastness, OHP transparency, and dispersibility in toner particles.

[0066] When a magnetic material is used as a colorant in toner, the magnetic material mainly consists of magnetic iron oxides such as iron(II,III) oxide and γ-iron oxide, and may also contain elements such as phosphorus, cobalt, nickel, copper, magnesium, manganese, aluminum, and silicon. These magnetic materials have a BET specific surface area of ​​2 to 30 m² obtained by nitrogen adsorption. 2 It is preferable that the amount be / g, which is 3 to 28m 2It is more preferable that the density is / g. Also, a Mohs hardness of 5 to 7 is preferred. As for the shape of the magnetic material, there are polyhedra, octahedra, hexahedrons, spheres, needle-like shapes, and flaky shapes, but those with less anisotropy, such as polyhedra, octahedra, hexahedrons, and spheres, are preferred for increasing image density.

[0067] The amount of colorant added is preferably 1 to 20 parts by mass per 100 parts by mass of the binder resin or polymerizable monomer constituting the binder resin. When magnetic powder is used, the amount is preferably 20 to 200 parts by mass, more preferably 40 to 150 parts by mass, per 100 parts by mass of the binder resin or polymerizable monomer constituting the binder resin.

[0068] The toner may contain other external additives, such as inorganic microparticles other than silica microparticles, in addition to silica microparticles. The toner can be obtained by externally adding silica microparticles and, if necessary, inorganic microparticles other than silica microparticles to the toner particles. Examples of inorganic microparticles include hydrotalcite compounds, strontium titanate, fatty acid metal salts, alumina, and metal oxide microparticles (inorganic microparticles) such as titanium dioxide, zinc oxide microparticles, cerium oxide microparticles, and calcium carbonate microparticles.

[0069] Furthermore, other external additives can include composite oxide nanoparticles using two or more metals, or two or more nanoparticles selected in any combination from this group. Furthermore, resin microparticles or organic-inorganic composite microparticles, which are a mixture of resin microparticles and inorganic microparticles, can also be used. Preferably, the toner contains titanium dioxide particles in addition to silica microparticles as an external additive. Other external additives may be hydrophobized using a hydrophobic treatment agent.

[0070] Examples of hydrophobic treatment agents include chlorosilanes such as methyltrichlorosilane, dimethyldichlorosilane, trimethylchlorosilane, phenyltrichlorosilane, diphenyldichlorosilane, t-butyldimethylchlorosilane, and vinyltrichlorosilane; Tetramethoxysilane, methyltrimethoxysilane, dimethyldimethoxysilane, phenyltrimethoxysilane, diphenyldimethoxysilane, o-methylphenyltrimethoxysilane, p-methylphenyltrimethoxysilane, n-butyltrimethoxysilane, i-butyltrimethoxysilane, hexyltrimethoxysilane, octyltrimethoxysilane, decyltrimethoxysilane, dodecyltrimethoxysilane, tetraethoxysilane, methyltriethoxysilane, dimethyldiethoxysilane, phenyltriethoxysilane, Diphenyldiethoxysilane, i-butyltriethoxysilane, decyltriethoxysilane, vinyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-chloropropyltrimethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-(2-aminoethyl)aminopropyltrimethoxysilane, γ-(2-aminoethyl) Alkoxysilanes such as (Tyl)aminopropylmethyldimethoxysilane; Silazanes such as hexaethyldisilazane, hexapropyldisilazane, hexabutyldisilazane, hexapentyldisilazane, hexahexyldisilazane, hexacyclohexyldisilazane, hexaphenyldisilazane, divinyltetramethyldisilazane, and dimethyltetravinyldisilazane; Silicone oils such as dimethyl silicone oil, methyl hydrogen silicone oil, methylphenyl silicone oil, alkyl-modified silicone oil, chloroalkyl-modified silicone oil, chlorophenyl-modified silicone oil, fatty acid-modified silicone oil, polyether-modified silicone oil, alkoxy-modified silicone oil, carbinol-modified silicone oil, amino-modified silicone oil, fluorine-modified silicone oil, and terminally reactive silicone oils; Siloxanes such as hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, hexamethyldisiloxane, and octamethyltrisiloxane; Examples of fatty acids and their metal salts include long-chain fatty acids such as undecylic acid, lauric acid, tridecylic acid, dodecylic acid, myristic acid, palmitic acid, pentadecylic acid, stearic acid, heptadecylic acid, arachidic acid, montanic acid, oleic acid, linoleic acid, and arachidonic acid, as well as salts of the above fatty acids with metals such as zinc, iron, magnesium, aluminum, calcium, sodium, and lithium.

[0071] Among these, alkoxysilanes, silazanes, and silicone oils are preferred because they facilitate hydrophobic treatment. These hydrophobic agents may be used individually or in combination of two or more. The content of the external additive is preferably 0.05 parts by mass or more and 20.0 parts by mass or less per 100 parts by mass of toner particles. The content of external additives other than silica fine particles is preferably 0.1 to 1.0 parts by mass, and more preferably 0.1 to 0.5 parts by mass, per 100 parts by mass of toner particles.

[0072] The weight-average particle size (D4) of the toner is preferably 3.0 μm to 12.0 μm, and more preferably 4.0 μm to 10.0 μm. A weight-average particle size (D4) of 3.0 μm to 12.0 μm provides good fluidity and allows for development that faithfully reproduces the latent image.

[0073] The complex modulus of elasticity G'(60°C) of the toner at 60°C is 4 × 10⁻⁶ 7 ~8×10 10 This is This is preferable, 4 × 10 8 ~1 × 10 10 It is more preferable that it be 4 × 10 9 ~8×10 9 It is even more preferable that G' (60℃) is suitable for cartridges during long-term printing. This indicates the durability of the toner when it is rubbed within the tumbler. Within the above range, the occurrence of developer streaks can be suppressed without hindering low-temperature fixing. G' (60℃) is for polyester. It can be controlled by adjusting the amount added.

[0074] The method for producing toner particles is not particularly limited, and known methods can be employed. For example, methods for directly producing toner in a hydrophilic medium include suspension polymerization, emulsification and agglutination, and dissolution and suspension. Alternatively, a grinding method may be used, and the toner obtained by the grinding method may be formed into hot spheres.

[0075] For example, suspension polymerization is a method for obtaining toner matrix particles by granulating a polymerizable monomer composition containing polymerizable monomers capable of producing resin, a release agent, and other additives as needed, in an aqueous medium, and polymerizing the polymerizable monomers contained in the polymerizable monomer composition. Furthermore, after the polymerization process is complete, the generated particles can be recovered by washing and filtration using known methods, and then dried to obtain toner matrix particles. The temperature may be increased during the latter half of the polymerization process. Furthermore, to remove unreacted polymerizable monomers or by-products, it is possible to partially remove the dispersion medium from the reaction system during the latter half of the polymerization process or after the polymerization process is completed.

[0076] Furthermore, toner can be obtained by adding silica fine particles to the obtained toner particles. Other external additives may be added as needed. From the viewpoint of the dispersibility of the external additive, the mixing time in the external additive step is preferably 0.5 minutes to 10.0 minutes, and more preferably 1.0 minute to 5.0 minutes.

[0077] Next, we will describe the measurement methods for each physical property. <Solid silica microparticles> 29 Methods for calculating D1 / D, D2 / D, D1 / D2, and (D / S) / B using Si-NMR DD / MAS measurements > Solid silica nanoparticles 29Si-NMR measurements are performed by separating silica nanoparticles from the toner surface. Below, we will discuss the method for separating silica nanoparticles from the toner surface and the solid-state method. 29 This document describes Si-NMR measurements.

[0078] <Method for separating silica microparticles from the toner surface> When using silica microparticles separated from the surface of the toner as the measurement sample, the separation of silica microparticles from the toner is performed using the following procedure. 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. 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.

[0079] After centrifugation, toner particles are present in the uppermost layer of the glass tube, while an inorganic microparticle mixture containing silica microparticles 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 inorganic microparticle mixture from the lower layer. The obtained toner particles are used to measure the surface abundance of the polyester resin, as described later. The centrifugation process is repeated so that the total amount of inorganic microparticle mixture obtained from the lower layer is 10 g or more.

[0080] Next, 10 g of the obtained inorganic fine particle mixture is added to a dispersion containing 100 mL of deionized water and 6 mL of 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. After centrifugation, silica microparticles are present in the uppermost layer of the glass tube, while other inorganic microparticles are present in the lower aqueous solution layer. The upper aqueous solution is collected, and centrifugation is repeated as needed to ensure sufficient separation. After drying the dispersion, the silica microparticles are collected. Next, the solid silica microparticles recovered from the toner particles. 29 The Si-NMR measurement will be performed under the measurement conditions shown below.

[0081] <Solid 29 DD / MAS measurement conditions for Si-NMR > solid 29 The DD / MAS measurement conditions for Si-NMR are as follows: Equipment: JNM-ECX5002 (JEOL RESONANCE) Temperature: room temperature Measurement method: DD / MAS method 29 Si 45° Sample tube: Zirconia 3.2mmφ 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)

[0082] After the above measurement, the solid silica nanoparticles 29 From the Si-NMR spectrum, multiple silane components with different substituents and bonding groups are separated into peaks in M, D, T, and Q units as shown below by curve fitting. Curve fitting is performed using EXcalibur for Windows (registered trademark) version 4.2 (EX series), software for JNM-EX400 manufactured by JEOL Ltd. Click "1D Pro" from the menu icon to load the measurement data. Next, select "Curve fitting function" from "Command" in the menu bar to perform curve fitting. Curve fitting is performed for each component so that the difference (synthetic peak difference) between the synthetic peak obtained by synthesizing each peak obtained by curve fitting and the peak of the measurement result is minimized. Unit of M: (R i )(R j )(R k )SiO 1 / 2 Formula (4) Unit of D: (R g )(R h )Si(O 1 / 2 )2 Formula (5) Unit of T: R m Si(O 1 / 2 )3 Formula (6) Unit of Q: Si(O 1 / 2 )4 Formula (7) In the formulas (4), (5), and (6), R i , R j , R k , R g , R h , R m represents an alkyl group such as a hydrocarbon group having 1 to 6 carbon atoms bonded to silicon, a halogen atom, a hydroxy group, an acetoxy group, or an alkoxy group.

[0083] Also, for the D unit peak, waveform separation is performed using the Voigt function, and the areas of peak D1 in the range exceeding -19 ppm and not exceeding -17 ppm and peak D2 in the range of -23 ppm or more and -19 ppm or less are calculated. After peak separation, the integral value of the D unit existing in the range of chemical shift of -25 to -15 ppm is calculated. Also, the total sum S of all integral values of M, D, T, and Q units existing in the range of -140 to 100 ppm is calculated, and the BET specific surface area B (m 2The ratio (D / S) / B is calculated by determining the (g) value. Additionally, D1 / D, D2 / D, and D1 / D2 are calculated from the peaks D1 and D2 obtained by waveform separation and the integral value of D. Furthermore, after performing the chloroform washing procedure described below on the silica nanoparticles, the same NMR measurement is performed to calculate the (D / S) / B ratio after washing.

[0084] <Cleaning of silica microparticles with chloroform> Place 100 mL of chloroform and 1 g of silica microparticles into a centrifuge tube and stir with a spatula or similar tool. Set the centrifuge tube in a KM Shaker and shake for 20 minutes at a rate of 350 strokes per minute. After shaking, transfer to a glass tube for a swing rotor and centrifuge at 3500 rpm for 30 minutes. Discard the supernatant, add another 100 mL of chloroform and shake, then repeat the centrifugation process twice. Collect the precipitated silica microparticles and vacuum dry them at 40°C for 24 hours to obtain washed silica microparticles.

[0085] <Flash of silica nanoparticle surface by time-of-flight secondary ion mass spectrometry (TOF-SIMS) Method for measuring ion content > TOF-SIMS measurement of silica nanoparticles is performed using silica nanoparticles separated from the toner surface by the method described above. For fragment ion measurement of the silica nanoparticle surface using TOF-SIMS, ULVAC-PHI's TRIFT-IV is used. The analysis conditions are as follows: Sample preparation: Silica microparticles 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 From the obtained mass profile of secondary ion mass / secondary ion charge (m / z), we check whether fragment ions corresponding to the structure shown in equation (1) are observed. For example, if the surface treatment agent is polydimethylsiloxane or cyclic siloxane, fragment ions are observed at positions such as m / z = 147, 207, and 221.

[0086] <Method for analyzing monomers in polyester resin components> [Separation of resin components from toner] The toner is dissolved in tetrahydrofuran (THF), and the solvent is removed from the resulting soluble matter under reduced pressure to obtain the tetrahydrofuran (THF) soluble component of the toner. The obtained tetrahydrofuran (THF) soluble component of the toner is dissolved in chloroform to prepare a sample solution with a concentration of 25 mg / mL. 3.5 mL of the obtained sample solution is injected into the apparatus described below, and under the conditions described below, the low molecular weight component derived from the release agent (molecular weight less than 2000) and the high molecular weight component derived from the resin component (molecular weight 2000 or more) are separated. Preparative GPC device: Preparative HPLC LC-980 model manufactured by Japan Analytical Industry Co., Ltd. Preparative columns: JAIGEL 3H, JAIGEL 5H (manufactured by Japan Analytical Industry Co., Ltd.) Eluent: Chloroform Flow rate: 3.5mL / min After separating the high molecular weight components derived from the resin, the solvent is removed by vacuum distillation, and the mixture is then dried under reduced pressure in a 90°C atmosphere for 24 hours. If high molecular weight components other than polyester resin are present, it can be determined whether or not they are polyester resin by performing the monomer analysis of polyester resin as shown below. Repeat the above procedure until approximately 100 mg of polyester resin is obtained. Dry the obtained polyester resin under reduced pressure at 40°C for 24 hours.

[0087] [Monomer analysis of polyester resin components] The types of monomers in the polyester resin components are determined by analyzing samples of each resin component separated from the toner using a pyrolysis GC / MS instrument under the following conditions. Measurement device: "Voyager" (product name, manufactured by ThermoElectron) Pyrolysis temperature: 600℃ Column: HP-1 (15m x 0.25mm x 0.25μm) Inlet: 300℃, Split: 20.0 Injection volume: 1.2mL / min Heating: 50℃ (4 min) - 300℃ (20℃ / min)

[0088] <Method for measuring fragment ions of polyester resin on the surface of toner particles using time-of-flight secondary ion mass spectrometry (TOF-SIMS) and calculation of the polyester resin abundance Sp (area %)> TOF-SIMS measurement of the polyester resin on the surface of toner particles is performed using toner particles separated from the toner by the method described above for separating silica microparticles from the toner surface. For fragment ion measurement of polyester resins using TOF-SIMS, we use the TRIFT-IV from ULVAC-PHI. The analysis conditions are as follows: Sample preparation: Toner particles 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

[0089] From the obtained mass profile of secondary ion mass / secondary ion charge number (m / z), we confirm whether fragment ions of the monomer species identified by the above monomer analysis are observed. We then calculate the value At by dividing this value by the total amount of ions counted in the toner particle measurement. Similar measurements are performed on polyester resin separated and purified using the above method, and the value Ap is obtained by dividing the obtained secondary ion mass / secondary ion charge number (m / z) by the total ion amount. The ratio of At to Ap (At / Ap) is taken as the abundance Sp of polyester resin on the surface of the toner particles. The arithmetic mean of 100 toner particles is used. Furthermore, to determine whether polyester resin is present on the surface of the toner particles, if a peak of fragment ions derived from the monomer species identified by the above monomer analysis is detected, it is determined that polyester resin is present on the surface of the toner particles.

[0090] <Measurement of the acid value of polyester resin> The acid value is the number of milligrams of potassium hydroxide required to neutralize the acid contained in 1 g of the sample. The acid value is measured according to JIS K0070-1992, and specifically, it is measured according to the following procedure. Dissolve 1.0 g of phenolphthalein in 90 mL of ethyl alcohol (95% by volume), add deionized water to make a total volume of 100 mL, and obtain a phenolphthalein solution. Dissolve 7 g of special grade potassium hydroxide in 5 mL of water and add ethyl alcohol (95 vol%) to make 1 L. Place the solution in an alkali-resistant container, taking care not to allow it to come into contact with carbon dioxide, etc., and leave it for 3 days. Then filter the solution to obtain potassium hydroxide solution. Store the obtained potassium hydroxide solution in an alkali-resistant container. The factor of the above potassium hydroxide solution is determined by taking 25 mL of 0.1 mol / L hydrochloric acid in an Erlenmeyer flask, adding a few drops of the above phenolphthalein solution, titrating with the above potassium hydroxide solution, and determining the titer from the amount of potassium hydroxide solution required for neutralization. The above 0.1 mol / L hydrochloric acid should be prepared in accordance with JIS K8001-1998.

[0091] 2.0 g of the pulverized crystalline polyester sample is accurately weighed into a 200 mL Erlenmeyer flask, and 100 mL of a toluene / ethanol (2:1) mixture is added. The sample is dissolved over 5 hours. Then, a few drops of the phenolphthalein solution are added as an indicator, and the sample is titrated with the potassium hydroxide solution. The titration endpoint is reached when the indicator turns a pale pink color for approximately 30 seconds. The titration procedure is the same as described above, except that no sample is used for the blank test (i.e., only a mixed solution of toluene / ethanol (2:1) is used). (3) Substitute the obtained results into the following formula to calculate the acid value. A = [(CB) × f × 5.61] / S Here, A is the acid value (mgKOH / g), B is the volume of potassium hydroxide solution added in the blank test (mL), C is the volume of potassium hydroxide solution added in the main test (mL), f is the factor of the potassium hydroxide solution, and S is the mass of the sample (g).

[0092] <Method for measuring the complex modulus G' of toner> The hardness of the toner is evaluated by the complex modulus G' at 60°C. A rotating plate rheometer "ARES" (manufactured by TA INSTRUMENTS) is used as the measuring instrument. For the measurement sample, 0.1 g of toner was weighed and, under room temperature (25°C), was pressure-molded into a disc shape with a diameter of 8.0 mm and a thickness of 1.5 ± 0.3 mm using a tablet molder. The sample is mounted on an 8.0 mm diameter parallel plate, heated from room temperature (25°C) to 100°C in 5 minutes, held for 3 minutes, and then cooled to 25°C over 10 minutes. Afterward, the temperature is maintained at 25°C for 30 minutes before measurement begins. At this time, the sample is set so that the initial normal force is 0. Furthermore, as described below, the effect of the normal force can be canceled during subsequent measurements by enabling automatic tension adjustment (Auto Tension Adjustment ON). Measurements are performed under the following conditions.

[0093] (1) Use a parallel plate with a diameter of 8.0 mm. (2) Frequency: 1 Hz. (3) Set the initial applied strain value (Strain) to 0.05%. (4) Measurements shall be taken in a temperature range of 25°C to 70°C with a heating rate of 2.0°C / min. The measurements shall be taken under the following automatic adjustment mode settings: Measurements shall be taken in automatic strain adjustment mode (Auto Strain). (5) Set Max Applied Strain to 20.0%. (6) Set the maximum torque (Max Allowed Torque) to 200.0 [g·cm] and the minimum torque (Min Allowed Torque) to 0.2 [g·cm]. (7) Set the Strain Adjustment to 20.0% of Current Strain. For measurement, use the Auto Tension mode. (8) Set Auto Tension Direction to Compression. (9) Set the Initial Static Force to 10g and the Auto Tension Sensitivity to 10.0g. (10) The operating conditions for Auto Tension are: Sample Modulus: 1.00 × 10 6 The value must be Pa or higher. Under the above conditions, determine the complex modulus G' at 60°C when measured at a frequency of 1 Hz.

[0094] <Method for measuring the Si-OH content of silica microparticles> The Si-OH content of silica nanoparticles can be determined using the silica nanoparticles separated from the toner by the method described above, and by the following method. Prepare a sample solution 1 by mixing 25.0 g of ethanol and 75.0 g of a 20% by mass aqueous sodium chloride solution. Also, accurately weigh 2.00 g of silica microparticles into a glass bottle, and prepare a sample solution 2 by adding a solvent obtained by mixing 25.0 g of ethanol and 75.0 g of a 20% by mass aqueous sodium chloride solution. The sample solution 2 is stirred with a magnetic stirrer for 5 minutes or more to disperse the silica microparticles. Next, for each of the sample solutions 1 and 2, while dropping a 0.1 mol / L aqueous sodium hydroxide solution at 0.01 mL / min, measure the pH change of the sample solution. Record the titration volume (L) of the aqueous sodium hydroxide solution when the pH reaches 9.0. From the following formula, the amount of Si-OH per 1 nm 2 per Sn (number / nm 2 ) can be calculated. Sn = {(a - b) × c × NA} / (d × e) a: Titration volume (L) of NaOH for sample solution 2 b: Titration volume (L) of NaOH for sample solution 1 c: Concentration (mol / L) of the NaOH solution used for titration NA: Avogadro number d: Mass (g) of the silica microparticles e: BET specific surface area (nm 2 / g: Specific surface area (m 2 / g) obtained below, converted)

[0095] <Method for measuring the BET specific surface area of silica microparticles> The BET specific surface area of the silica microparticles is measured by the following procedure. As the measuring device, use the "Automatic Specific Surface Area and Pore Size Distribution Measuring Device Tri Star3000 (manufactured by Shimadzu Corporation)" which adopts the gas adsorption method by the constant volume method as the measuring method. The setting of the measuring conditions and the analysis of the measurement data are performed using the dedicated software "TriStar3000 Version 4.00" attached to this device. Also, a vacuum pump, a nitrogen gas pipe, and a helium gas pipe are connected to the device. Nitrogen gas is used as the adsorption gas, and the value calculated by the BET multi-point method is taken as the BET specific surface area. The BET specific surface area is calculated as follows: First, nitrogen gas is adsorbed onto silica nanoparticles, and the equilibrium pressure P(P) inside the sample cell at that time is calculated. a ) and the amount of nitrogen adsorbed by the magnetic material V a (mol·g -1 ) is measured. Then, the equilibrium pressure P(P) in the sample cell is measured. a ) is the saturated vapor pressure P of nitrogen o (P a The relative pressure P is the value obtained by dividing by ). r With the horizontal axis representing the amount of nitrogen adsorption V, a (mol·g -1 An adsorption isotherm is obtained with ) as the vertical axis. Next, the monolayer adsorption amount V is the amount of adsorption required to form a monolayer on the surface of silica nanoparticles. m (mol·g -1 ) is calculated by applying the following BET formula. P r / V a (1-P r ) = 1 / (V m ×C)+(C-1)×P r / (V m ×C) (Here, C is the BET parameter, which is a variable that varies depending on the type of sample being measured, the type of adsorbed gas, and the adsorption temperature.) The BET formula uses P as the X-axis. r , Y axis P r / V a (1-P r If we assume that the slope is (C-1) / (V m ×C), the intercept is 1 / (V m This can be interpreted as a straight line (×C) (this line is called a BET plot). The slope of a line = (C-1) / (V m ×C) Intercept of a straight line = 1 / (V m ×C) P r Measured values ​​and P r / V a (1-P r By plotting the measured values ​​of ) on a graph and drawing a straight line using the least squares method, the slope and intercept values ​​of that line can be calculated. Solving the simultaneous equations for the slope and intercept using these values, we get V mAnd C can be calculated. Furthermore, V calculated above m and the molecular occupied cross-section of a nitrogen molecule (0.162 nm 2 ) Based on the following formula, the BET specific surface area S(m²) of silica nanoparticles is calculated. 2 Calculate the value (per g). S=V m ×N×0.162×10 -18 (Here, N is Avogadro's number (mol) -1 ) is. )

[0096] Measurements using this device are performed specifically according to the following procedure. Thoroughly wash and dry a dedicated glass sample cell (stem diameter 3 / 8 inch, volume 5 mL) and accurately weigh its tare. Then, using a funnel, place 0.1 g of silica microparticles into the sample cell. Place the sample cell containing the silica microparticles into the "Vacuprep 061 (Shimadzu Corporation)" pretreatment device, which is connected to a vacuum pump and nitrogen gas piping, and continue vacuum degassing at 23°C for 10 hours. During vacuum degassing, the valve is adjusted to gradually remove the silica particles while preventing them from being drawn into the vacuum pump. The pressure inside the cell gradually decreases as degassing progresses, eventually reaching 0.4 Pa (approximately 3 mTorr). After vacuum degassing is complete, nitrogen gas is gradually injected to return the sample cell to atmospheric pressure, and the sample cell is removed from the pretreatment device. The mass of the sample cell is then accurately weighed, and the exact mass of the silica nanoparticles is calculated from the difference between the weighed mass and the tare weight. During this process, the sample cell is sealed with a rubber stopper to prevent contamination of the silica nanoparticles with moisture from the atmosphere.

[0097] Next, a special isothermal jacket is attached to the sample cell containing silica nanoparticles. Then, a special filler rod is inserted into the sample cell, and the sample cell is set into the analysis port of the apparatus. The isothermal jacket is a cylindrical component with a porous inner surface and an impermeable outer surface, capable of drawing up liquid nitrogen to a certain level by capillary action. Next, the free space of the sample cell, including the connecting device, is measured. The free space is calculated by first measuring the volume of the sample cell using helium gas at 23°C, then cooling the sample cell with liquid nitrogen and similarly measuring the volume of the sample cell using helium gas, and converting the difference between these volumes. The saturated vapor pressure of nitrogen P is also measured. o (P a ) is P built into the device o It is measured separately and automatically using a tube.

[0098] Next, after vacuum degassing the sample cell, the sample cell is cooled with liquid nitrogen while continuing vacuum degassing. Then, nitrogen gas is gradually introduced into the sample cell to adsorb nitrogen molecules onto the silica nanoparticles. At this time, the equilibrium pressure P(P) a By continuously measuring the adsorption isotherm, an adsorption isotherm can be obtained, and this adsorption isotherm is then converted into a BET plot. Note that the relative pressure P from which the data is collected r The points are set to a total of 6 points: 0.05, 0.10, 0.15, 0.20, 0.25, and 0.30. A straight line is drawn from the obtained measurement data using the least squares method, and the slope and intercept of that line are used to determine V m Calculate this V. m Using the value of , the BET specific surface area of ​​the silica nanoparticles is calculated as described above.

[0099] <Method for calculating the coverage ratio (Ssi) of toner particles by silica microparticles on the surface of toner particles> The coverage rate (Ssi) of silica microparticles on the surface of toner particles is calculated from backscattered electron images obtained by scanning electron microscopy (SEM). Backscattered electron images are also called "compositional images," and particles with smaller atomic numbers appear darker, while those with larger atomic numbers appear brighter. Backscattered electron images of toner are obtained under the following observation conditions. The method for obtaining backscattered electron images of toner and the method for calculating the coverage rate of silica microparticles on the surface of toner particles are described below.

[0100] <Method for obtaining backscattered electron images of toner> Equipment used: ULTRA PLUS manufactured by Carl Zeiss Microscopy Co., Ltd. Acceleration voltage: 1.0kV WD: 2.5mm Aperture Size: 30.0 μm Detection signal: EsB (Energy-selective backscattered electrons) EsB Grid: 700V Observation magnification: 20,000x 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). 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 toner's outermost surface, preventing charge-up of undeposited samples, and selectively detecting high-energy backscattered electrons. The observation field should be selected to cover areas with low toner curvature.

[0101] <Method for calculating the silica coating rate of toner> The silica coverage is obtained by analyzing the backscattered electron image of the toner surface obtained by the above method using the image processing software ImageJ (developed by Wayne Rashand). The procedure is as follows. First, convert the backscattered electron image to 8-bit using the Image menu's Type option. Next, reduce image noise by setting the Median diameter to 2.0 pixels using the Process menu's Filters option. Then, select the entire backscattered electron image using the Rectangle Tool on the toolbar. Subsequently, select Threshold from the Image menu's Adjust option and specify a luminance threshold (85-128 (256 gradations)) so that only luminance pixels originating from silica nanoparticles within the backscattered electrons are selected. Finally, select Measure from the Analyze menu to calculate the area percentage (area %) of the selected luminance portion in the backscattered electron image. The above procedure is performed for 20 fields of view for the toner to be evaluated, and the arithmetic mean is defined as the coverage rate (Ssi) of silica microparticles on the surface of the toner particles.

[0102] <Method for measuring the number-average particle size of silica microparticles> The number-average particle size of silica microparticles is measured from secondary electron images obtained by scanning electron microscopy (SEM) observation of the toner surface.

[0103] (Method for acquiring secondary electron images of toner) Equipment used: ULTRA PLUS manufactured by Carl Zeiss Microscopy Co., Ltd. Acceleration voltage: 1.0kV WD: 2.5mm Aperture Size: 30.0 μm Detection signal: SE2 (secondary electron image) Observation magnification: 50,000x Resolution: 1024 x 768 pixels Pre-treatment: Toner is sprayed onto carbon tape (Pt deposition is not performed). From the obtained secondary electron images, the longest diameter of 100 primary silica particles on the surface of the toner particles is measured, and the average value is taken as the number-average particle size of the silica particles.

[0104] <Measurement of silica microparticle content> The silica microparticle content is determined by measuring the mass of the silica microparticles and toner particles obtained by the above-described method of separating silica microparticles from the toner surface.

[0105] <Method for measuring the weight-average particle size (D4) of toner> The weight-average particle size (D4) of the toner is measured using the Coulter Multisizer, a precision particle size distribution analyzer with a pore electrical resistance method equipped with a 100 μm aperture tube. Using the "Beckman Coulter Multisizer 3" (registered trademark, manufactured by Beckman Coulter) and the accompanying dedicated software "Beckman Coulter Multisizer 3 Version 3.51" (manufactured by Beckman Coulter) for setting measurement conditions and analyzing measurement data, measurements are taken with an effective number of measurement channels of 25,000, and the measurement data is analyzed and calculated. The electrolytic aqueous solution used for measurement is prepared by dissolving special grade sodium chloride in deionized water to a concentration of approximately 1% by mass; for example, "ISOTON II" (manufactured by Beckman Coulter) can be used. Before performing measurements and analysis, configure the dedicated software as follows. In the dedicated software's "Change Standard Measurement Method (SOM)" screen, set the total count in control mode to 50,000 particles, the number of measurements to 1, and the Kd value to the value obtained using "Standard Particle 10.0 μm" (manufactured by Beckman Coulter). Pressing the Threshold / Noise Level measurement button will automatically set the threshold and noise level. Also, set the current to 1600 μA, the gain to 2, and the electrolyte to ISOTON II, and then the aperture after measurement. Check the "Flash" option in the CharTube settings. In the dedicated software's "Pulse to Particle Size Conversion Settings Screen," set the bin spacing to logarithmic particle size, the particle size bins to 256 particle size bins, and the particle size range to 2 μm or more and 60 μm or less.

[0106] The specific measurement method is as follows: (1) Pour approximately 200 ml of the electrolytic solution into a 250 ml round-bottom glass beaker specifically designed for the Multisizer 3, set it on the sample stand, and stir the mixture with the stirrer rod at 24 revolutions per second in a counterclockwise direction. Then, use the "Aperture Tube Flash" function of the dedicated software to remove any dirt and air bubbles from inside the aperture tube. (2) Place approximately 30 ml of the electrolytic aqueous solution into a 100 ml flat-bottomed glass beaker, and add approximately 0.3 ml of a diluted solution 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.) diluted three times by mass with deionized water as a dispersant. (3) Two oscillators with an oscillation frequency of 50 kHz are built in with their phases shifted by 180 degrees, and a predetermined amount of deionized water is placed in the water tank of an ultrasonic dispersion device called "Ultrasonic Dispersion System Tetora150" (manufactured by Nikko Bios Co., Ltd.) with an electrical output of 120 W. Approximately 2 ml of the aforementioned Contaminon N is added to this water tank. (4) Place the beaker from (2) into the beaker fixing hole of the ultrasonic disperser and operate the ultrasonic disperser. Then, adjust the height of the beaker so that the resonance state of the liquid surface of the electrolytic aqueous solution inside the beaker is maximized. (5) While irradiating the electrolytic aqueous solution in the beaker described in (4) with ultrasound, add approximately 10 mg of toner to the electrolytic aqueous solution in small amounts and disperse it. Continue the ultrasonic dispersion treatment for another 60 seconds. During ultrasonic dispersion, adjust the water temperature in the tank to be between 10°C and 40°C as appropriate. (6) Using a pipette, the electrolytic aqueous solution (5) containing the dispersed toner is dropped into the round-bottom beaker (1) placed in the sample stand, and the concentration is adjusted to approximately 5%. The measurement is then continued until the number of particles measured reaches 50,000. (7) The measurement data is analyzed using the dedicated software attached to the device, and the weight-average particle size (D4) is calculated. Note that the "Average Diameter" on the Analysis / Volume Statistics (Arithmetic Mean) screen when the dedicated software is set to Graph / Volume % is the weight-average particle size (D4). [Examples]

[0107] The present invention will be described in more detail below with reference to manufacturing examples and embodiments, but these are not intended to limit the present invention in any way. Note that all parts in the following formulations are in parts by mass.

[0108] <Example of silica nanoparticle production> Untreated dry silica as small-particle inorganic fine particles (number-average particle size of primary particles: 15 nm, BET specific surface area: 200 m²) 2 ( / g) and untreated dry silica as large-particle inorganic fine particles (number average particle size of primary particles 35 nm, BET specific surface area 50 m²) 2 The material ( / g) was added in a mass ratio of 10:1 and heated to 330°C while being stirred to a fluid state. The reactor was sealed by purging the inside with nitrogen gas, and octamethylcyclotetrasiloxane was sprayed using a spray nozzle as the first surface treatment agent until the gauge pressure reached 200 kPa, and then mixed. After that, heating and stirring were continued for 1 hour to allow the reaction to proceed and complete the coating treatment. After the treatment, the reaction system was replaced with a nitrogen atmosphere and heated again to 330°C. Subsequently, as a second surface treatment agent, 10 parts of dimethyl silicone oil (Shin-Etsu Chemical Co., Ltd. KF-96-50CS) was sprayed onto 100 parts of untreated dry silica, and a similar coating treatment was carried out for 1 hour to obtain silica fine particles 1. The physical properties of silica fine particles 1 are shown in Table 1-2.

[0109] <Manufacturing examples of silica microparticles 2-5, 12, 14, 19> The reaction time of the first surface treatment agent and the amount of the second surface treatment agent and the treatment temperature are shown in Table 1-1. Silica nanoparticles 2-5, 12, 14, and 19 were obtained in the same manner as the manufacturing example of silica nanoparticle 1, except for the change to [specific component]. Table 1-1 shows the structure of the substituents of the compound represented by formula (3).

[0110] <Manufacturing examples of silica microparticles 6-11, 13, 15, 18, and 20> As shown in Table 1-1, silica nanoparticle substrates were introduced, and the second surface treatment agent was a carbinol-modified silicone oil (KF-6002, manufactured by Shin-Etsu Chemical Co., Ltd.). Except for changing the BET specific surface area of ​​the untreated dry silica introduced, the reaction time of the first surface treatment agent, the amount of the second surface treatment agent, and the treatment temperature of the second surface treatment agent as shown in Table 1-1, silica nanoparticles 6-11, 13, 15, 18, and 20 were obtained in the same manner as the production example of silica nanoparticle 1.

[0111] <Example of manufacturing silica microparticles 21> Untreated dry silica as inorganic fine particles (BET specific surface area 200 m²) 2 The silica ( / g) was added and heated to 250°C while being stirred to a fluid state. The reactor was sealed by purging the inside with nitrogen gas, and 25 parts hexamethyldisilazane was sprayed using a spray nozzle as the first surface treatment agent for 100 parts untreated dry silica. Then, heating and stirring were continued for 1 hour to coat the silica, and silica fine particles 21 were obtained.

[0112] [Table 1-1] In Table 1-1, base BET / m 2 / g represents the BET specific surface area of ​​the silica nanoparticle substrate. For silica nanoparticles 1-5 and 12-20, the substrate BET / m 2 The / g column shows the BET specific surface area of ​​200m². 2 / g small particle size silica microparticles and 50m 2 This indicates that large-particle silica nanoparticles were used in a mass ratio of small-particle silica to large-particle silica of 10:1. D4 represents octamethylcyclotetrasiloxane, and HMDS represents hexamethyldisilazane. Regarding the quantity, HMDS indicates parts.

[0113] [Table 1-2] In Table 1-2, B is the specific surface area B(m²) of the silica nanoparticles. 2 The value is ( / g). Before washing (D / S) / B is the solid silica fine particles. 29 The ratio value (D / S) / B is the ratio value obtained in the Si-NMR DD / MAS method analysis. The value after washing (D / S) / B is the ratio value (D / S) / B after washing the silica nanoparticles with chloroform. For example, the value of "1.5E-03" is "1.5 × 10 -3 This indicates that it is ".

[0114] <Manufacturing of Polyester Resin 1> Terephthalic acid: 75 parts Bisphenol A-propylene oxide 2 molar adduct: 100 parts Tetrabutoxytitanate: 0.125 parts The above polyester monomer was charged into an autoclave equipped with a vacuum device, water separator, nitrogen gas introduction device, temperature measuring device, and stirring device, and the reaction was carried out at 200°C for 5 hours under a nitrogen atmosphere and atmospheric pressure. Then, 2.1 parts of trimellitic acid and 0.120 parts of tetrabutoxytitanate were added, and the reaction was carried out at 220°C for 3 hours, and further reacted under reduced pressure of 10-20 mmHg for 2 hours to obtain polyester resin 1. The properties of the obtained polyester resin 1 were as follows: acid value = 8.3 mg KOH / g, weight-average molecular weight (Mw) = 11000, and glass transition temperature = 72.5°C.

[0115] <Examples of manufacturing polyester resins 2-5> Polyester resins 2-5 were obtained in the same manner as in Polyester Resin Production Example 1, except that the types and amounts of raw materials such as terephthalic acid and bisphenol A-propylene oxide 2 molar adduct were changed as shown in Table 2. The physical properties are shown in Table 2. [Table 2] In the table, TPA represents terephthalic acid, BPA-PO represents bisphenol A-propylene oxide 2-mol adduct, and TMA represents trimellitic acid. The unit of acid value is mgKOH / g.

[0116] <Example of Toner 1 manufacturing> 900 parts of deionized water heated to 60°C were mixed with 2.3 parts of tricalcium phosphate, and stirred at 10,000 rpm using a TK homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.) to obtain an aqueous medium. In addition, the following materials were uniformly dissolved and mixed at 100 rpm using a propeller-type stirrer to prepare a resin-containing monomer. • Styrene 45.0 parts n-butyl acrylate 25.0 parts • Polyester resin 1 4.0 parts

[0117] Furthermore, the following materials were dispersed in an attritor (manufactured by Mitsui Miike Chemical Machinery Co., Ltd.) to obtain a monomer containing fine colorants. • Styrene 30.0 parts • Carbon Black 7.4 parts • Charge control agent Bontron E-88 (manufactured by Orient Chemical Co., Ltd.) 1.0 part • Wax HNP-51 (manufactured by Nippon Seiro Co., Ltd.) 9.0 parts

[0118] Next, the finely particulate colorant-containing monomer and the resin-containing monomer were uniformly mixed to obtain a polymerizable monomer composition. Then, the polymerizable monomer composition was heated to 60°C, and subsequently, the polymerizable monomer composition was added to the aqueous medium to granulate the polymerizable monomer composition and form particles of the polymerizable monomer composition. Then, 10.0 parts of the polymerization initiator tert-butyl peroxypivalate were added, and granulation was continued for 10 minutes. Subsequently, the mixture was transferred to a propeller-type stirrer and stirred at 100 rpm while reacting at 75°C for 5 hours. After that, the temperature was raised to 85°C and the reaction was continued for another 5 hours to carry out the polymerization reaction. After the polymerization reaction was complete, the slurry containing the particles was cooled to room temperature (25°C), and hydrochloric acid was added to the slurry to form phosphorus. acid Tricalcium was dissolved, filtered, and washed with water to obtain wet colored particles. These wet colored particles were then dried at 40°C for 72 hours to obtain toner particles 1.

[0119] <Manufacturing of Toner 1> Using an FM mixer (FM-10B manufactured by Nippon Coke Industries Co., Ltd.), a toner mixture was obtained by mixing toner particles (1:100 parts), silica fine particles (1:0.6 parts), and titanium dioxide particles (average particle size 1.2 μm) (0.2 parts) for 180 seconds at a rotation speed of 3500 rpm. Subsequently, coarse particles were removed using a 300-mesh (48 μm opening) sieve to obtain toner 1. The manufacturing conditions and physical properties are shown in Table 3.

[0120] <Toner 2-33> Toners 2 through 33 were manufactured using the same procedure as in the manufacturing example of Toner 1, except that the type of polyester resin, the amount of polyester resin particles added, the type of silica microparticles, and the number of silica microparticles added were changed as shown in Table 3. The manufacturing conditions and physical properties are shown in Table 3.

[0121] [Table 3]

[0122] The following evaluations were performed using the obtained toner. <Evaluation of image streaks in the initial and post-endurance state> Image streaks are vertical streaks approximately 0.5 mm long that occur when toner cracks due to friction within the cartridge during prolonged printing. This image defect is more easily observed when printing full-screen halftone images. A modified Canon LBP712Ci was used as the image forming machine. The process speed of the main unit was modified to 250 mm / sec. Necessary adjustments were made to enable image forming under these conditions. In addition, the toner was removed from the black and cyan cartridges and replaced with 50g each of the toner to be evaluated. The toner load was 1.0 mg / cm². 2 That's what I decided.

[0123] Image streaking during continuous use under normal temperature and humidity conditions (23°C, 60%RH) was evaluated. Xerox 4200 paper (Xerox Corporation, 75g / m²) was used as the evaluation paper. 2 ) was used. Under normal temperature and humidity conditions, 1000 images were printed using an intermittent continuous operation method, outputting two "E" character images with a print density of 1% every 4 seconds. Afterward, a 50% halftone image was printed across the entire surface, and the presence or absence of streaks was observed. The evaluation results at this stage were defined as the initial image streaks (initial streaks). Furthermore, after 14000 more images were printed using the intermittent continuous operation method, a 50% halftone image was printed across the entire surface, and the presence or absence of streaks was observed. The following was observed. The evaluation results at this time were defined as the image streaks after endurance (endurance streaks). A to C were judged to be good. The evaluation results are shown in Table 4. (Evaluation criteria for development streaks) A: No streaks or toner lumps occurred. B: There are no streaks in a spotted pattern, but there are 1 - 2 small toner lumps. C: There are 1 - 2 spotted streaks at the ends, or there are 3 - 4 small toner lumps. D: There are 1 - 2 spotted streaks over the entire surface, or there are 5 - 6 small toner lumps. E: There are 3 or more spotted streaks over the entire surface, or there are 7 or more small toner lumps.

[0124] <Chargeability and toner scattering evaluation in high - temperature and high - humidity environment> Considering the fixing performance evaluation on a high - speed machine, the HP LaserJet Enterprise M609dn was modified to a process speed of 500 mm / sec for use. Also, it was modified so that an external power supply could be connected to change the transfer bias, and the charge stability and toner scattering were evaluated. After leaving the above - mentioned image - forming tester and the toner cartridge filled with the evaluation toner in a high - temperature and high - humidity environment of 32.5°C / 80%RH for 20 or 30 days, a test was conducted to print 20,000 sheets of a horizontal line pattern in which 4 - dot horizontal lines were printed every 176 dots using the above - mentioned image - forming tester.

[0125] Before and after the above - mentioned test, the charge amount (μC / g) of the toner on the developing carrier in the toner cartridge was measured using a blow - off powder charge amount measuring device TB - 200 (manufactured by Toshiba Chemical Corporation), and the chargeability in the high - temperature and high - humidity environment was evaluated. The larger the absolute value of the chargeability numerical value, the higher the chargeability and the better the environmental stability. Also, the 20,000th image sample in the above - mentioned test was visually inspected and the toner scattering was evaluated according to the following criteria. The evaluation ranks of the charge amount and toner scattering were determined and evaluated as follows. (Evaluation criteria for charge amount) S: Charge amount is less than - 25.0 μC / g A: Charge amount is - 25.0 μC / g or more and less than - 20.0 μC / g B: Charge amount is - 20.0 μC / g or more and less than - 15.0 μC / g C: Charge amount is - 15.0 μC / g or more and less than - 10.0 μC / g D: Charge amount is -10.0 μC / g or more

[0126] (Evaluation criteria for toner scattering) S: No toner scattering occurs in the developing unit in the evaluation after 30 days of leaving A: No toner scattering occurs in the developing unit in the evaluation after 20 days of leaving B: Although toner drops are observed on the developing blade in the evaluation after 20 days of leaving, there is no problem with the image. C: One toner scatter occurs on the image in the evaluation after 20 days of leaving D: Two or more toner scatters occur on the image in the evaluation after 20 days of leaving The occurrence of "toner scattering" in this evaluation means that in the downstream part from the toner regulating part of the developing roller, the toner is not held on the developing roller and the toner drops on the developing blade. If image formation continues in the state where toner scattering occurs, it will develop into contamination of the image forming body and the recording paper, resulting in a decrease in image quality.

[0127]

Table 4

[0128] The present disclosure relates to the following configuration. (Configuration 1) A toner containing toner particles containing a polyester resin and silica fine particles on the surface of the toner particles, In the measurement by time-of-flight secondary ion mass spectrometry of the silica fine particles, fragment ions corresponding to the structure represented by the following formula (1) are observed, TIFF0007881370000011.tif37153 In the formula (1), n represents an integer of 1 or more, When 2.00 g of the silica fine particles are dispersed in a mixed solution of 25.0 g of ethanol and 75.0 g of a 20 mass% NaCl aqueous solution and a titration operation is performed using sodium hydroxide, Sn defined by Sn = {(a - b) × c × NA} / (d × e) satisfies the following formula (2), 0.05 ≤ Sn ≤ 0.20 ···(2) In formula (2), a is the amount of NaOH titration (L) required to adjust the mixture containing the dispersed silica particles to pH 9.0. b is the amount of NaOH titration (L) required to adjust a mixture of 25.0 g of ethanol and 75.0 g of 20% by mass NaCl aqueous solution to pH 9.0. c is the concentration (mol / L) of the NaOH solution used in the titration. NA is Avogadro's number, d is the mass (g) of the silica fine particles, e is the BET specific surface area (nm) of the silica nanoparticles. 2 / g) Solid silica fine particles 29 In the chemical shift obtained by the Si-NMR DD / MAS method, D is the area of ​​the peaks with peak tops in the range of -25 to -15 ppm, S is the sum of the areas of the M, D, T, and Q unit peaks in the range of -140 to 100 ppm, and B is the specific surface area of ​​the silica nanoparticles. 2 When (D / S) is set to (g), the ratio of (D / S) to B, (D / S) / B, is 5.7 × 10 -4 ~4.9×10 -3 And, The (D / S) / B value measured after washing the silica microparticles with chloroform was 1.7 × 10⁻⁶. -4 ~4.9×10 -3 And, In the chemical shift, when D1 is defined as the area of ​​the peaks where the peak top is located in the range between -19 ppm and -17 ppm, the ratio of D1 to D (D1 / D) is between 0.09 and 0.32. The polyester resin is present on the surface of the toner particles. A toner characterized by the following features. (Configuration 2) The toner according to configuration 1, wherein when the proportion of the polyester resin on the surface of the toner particles is defined as Sp (area %), Sp is 50 area % or more. (Composition 3) The toner according to configuration 1 or 2, wherein, in the chemical shift, when D2 is the area of ​​the peaks where the peak top is in the range of -23 to -19 ppm, the ratio of D1 to D2 (D1 / D2) is 0.15 to 0.42. (Composition 4) The toner according to any of configurations 1 to 3, wherein the ratio of D2 to D (D2 / D) is between 0.30 and 0.90. (Composition 5) When the coverage rate of the toner particles by the silica fine particles on the surface of the toner is calculated from the scanning electron microscope image of the toner surface, and this is denoted as Ssi, The toner according to any of configurations 1 to 4, wherein the Ssi is 30 area % or more. (Composition 6) Let Sp (area %) be the percentage of the polyester resin present on the surface of the toner particles. When the coverage rate of the toner particles by the silica fine particles on the surface of the toner is calculated from the scanning electron microscope image of the toner surface, and this is denoted as Ssi, A toner according to any of configurations 1 to 5, wherein the ratio of Sp to Ssi (Sp / Ssi) is between 0.70 and 2.50. (Composition 7) The toner according to any one of configurations 1 to 6, wherein the content of the silica fine particles is 0.3 to 2.0 parts by mass per 100 parts by mass of the toner particles. (Composition 8) The toner according to any one of configurations 1 to 7, wherein the number-average particle size of the primary particles of the silica fine particles is 5 to 50 nm. (Composition 9) The toner according to any one of configurations 1 to 8, wherein the silica fine particles are surface-treated with at least the compound represented by the following formula (3). TIFF0007881370000012.tif37153 (R in equation (3)) 1 , R 2 Each of these is independently a carbinol group, a hydroxyl group, an epoxy group, a carboxyl group, an alkyl group, or a hydrogen atom, and m is an integer from 1 to 200. (Composition 10) Let Sp (area %) be the percentage of the polyester resin present on the surface of the toner particles. When the acid value of the polyester resin is Av(mgKOH / g), The Av is between 2.0 and 30.0. The toner according to any of configurations 1 to 9, wherein (Av / Sp) / Sn, calculated from Sp, Av, and Sn, is between 0.20 and 7.00. (Composition 11) The toner according to any one of configurations 1 to 10, wherein the silica fine particles are a silicone oil-treated product of silica fine particles treated with a cyclic siloxane.

Claims

1. A toner containing polyester resin toner particles and silica fine particles on the surface of the toner particles, In time-of-flight secondary ion mass spectrometry measurements of the silica nanoparticles, fragment ions corresponding to the structure shown in the following formula (1) were observed. In formula (1), n ​​represents an integer of 1 or more, When 2.00 g of the silica fine particles were dispersed in a mixture of 25.0 g of ethanol and 75.0 g of a 20% by mass NaCl aqueous solution and titrated using sodium hydroxide, Sn, defined as Sn = {(a-b) × c × NA} / (d × e), satisfies the following equation (2): 0.05 ≤ Sn ≤ 0.20 ... (2) In formula (2), a is the amount of NaOH titration (L) required to adjust the mixture containing the dispersed silica fine particles to pH 9.

0. b is the amount of NaOH titration (L) required to adjust the pH of a mixture of 25.0 g of ethanol and 75.0 g of 20% by mass NaCl aqueous solution to 9.

0. c is the concentration (mol / L) of the NaOH solution used in the titration. NA is Avogadro's number, d is the mass (g) of the silica fine particles, e is the BET specific surface area (nm) of the silica nanoparticles. ２ / g) and Solid silica fine particles ２９ In the chemical shift obtained by the Si-NMR DD / MAS method, D is the area of ​​the peaks with peak tops in the range of -25 to -15 ppm, S is the sum of the areas of the M, D, T, and Q units of the peaks in the range of -140 to 100 ppm, and B is the specific surface area of ​​the silica nanoparticles (m²). ２ When / g) The ratio of (D / S) to B, (D / S) / B, is 5.7 × 10 －４ ~4.9 x 10 －３ And, The (D / S) / B value measured after washing the silica microparticles with chloroform was 1.7 × 10⁻⁶. －４ ~4.9 x 10 －３ And, In the chemical shift, when D1 is defined as the area of ​​the peaks where the peak top is located in the range of -19 ppm to -17 ppm, the ratio of D1 to D (D1 / D) is between 0.09 and 0.

32. The polyester resin is present on the surface of the toner particles. A toner characterized by the following features.

2. The toner according to claim 1, wherein when the percentage of the polyester resin present on the surface of the toner particles is denoted as Sp (area %), Sp is 50 area % or more.

3. The toner according to claim 1 or 2, wherein, in the chemical shift, when D2 is the area of ​​the peaks where the peak top is in the range of -23 to -19 ppm, the ratio of D1 to D2 (D1 / D2) is 0.15 to 0.

42.

4. The toner according to claim 3, wherein the ratio of D2 to D (D2 / D) is 0.30 to 0.

90.

5. The toner according to claim 4, wherein the ratio of D2 to D (D2 / D) is 0.37 to 0.

66.

6. When the coverage rate of the silica fine particles on the surface of the toner particles, calculated from the scanning electron microscope observation image of the toner surface, is denoted as Ssi, The toner according to claim 1 or 2, wherein the Si is 30 area percent or more.

7. The percentage of the polyester resin on the surface of the toner particles is defined as Sp (area %). When the coverage rate of the silica fine particles on the surface of the toner particles, calculated from the scanning electron microscope observation image of the toner surface, is denoted as Ssi, The toner according to claim 1 or 2, wherein the ratio of Sp to Si (Sp / Si) is 0.70 to 2.

50.

8. The toner according to claim 1 or 2, wherein the content of the silica fine particles is 0.3 to 2.0 parts by mass per 100 parts by mass of the toner particles.

9. The toner according to claim 1 or 2, wherein the number-average particle size of the primary particles of the silica fine particles is 5 to 50 nm.

10. The toner according to claim 1 or 2, wherein the silica fine particles are surface-treated with at least a compound represented by the following formula (3). (R in formula (3) １ , R ２ is each independently a carbinol group, a hydroxy group, an epoxy group, a carboxy group, an alkyl group, or a hydrogen atom, and m is an integer of 1 to 200.)

11. The percentage of the polyester resin on the surface of the toner particles is defined as Sp (area %). When the acid value of the polyester resin is Av (mg KOH / g), The Av is between 2.0 and 30.

0. The toner according to claim 1 or 2, wherein (Av / Sp) / Sn, calculated from Sp, Av, and Sn, is between 0.20 and 7.

00.

12. The toner according to claim 1 or 2, wherein the silica fine particles are a silicone oil-treated product of silica fine particles treated with a cyclic siloxane.

13. The silica fine particles contain small-particle silica fine particles and large-particle silica fine particles, The number-average particle size of the primary particles of the small-particle silica nanoparticles is 5 to 25 nm. The number-average particle size of the primary particles of the large-particle silica nanoparticles is greater than 25 nm and less than or equal to 50 nm. The toner according to claim 1 or 2, wherein the mass-based content ratio of the small-particle silica microparticles and the large-particle silica microparticles (small-particle silica microparticles:large-particle silica microparticles) is 20:1 to 5:1.

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