toner

Abstract

To provide a toner excellent in low temperature fixability and image preservability.SOLUTION: A toner has a toner particle containing crystalline polyester including a monomer having a straight-chain hydrocarbon chain having 8-12 carbon atoms, and surface-treated silica fine particles on a surface of the toner particle. When peaks PD1, PD2, PQ which correspond to silicon atoms in a structure separately represented by the formula are observed, and the peak areas are defined as SD1, SD2, SQ, respectively, and when PD1w, PD2w, PQw which correspond to PD1 after washing with hexane are observed, and the peak areas are defined as SD1w, SD2w, SQw, respectively, 1.2≤(SD1+SD2) / SD1≤6.2, Ca=(SD1+SD2) / SQ×100 (a), Cb=(SD1w+SD2w) / SQw×100 (b), and (Ca-Cb) / Ca×100≤5.0 (c) are satisfied. When the silica BET specific surface area after washing with hexane is defined as S, 0.04≤Cb / {(SD1w+SD2w) / SD1w} / S≤0.20 (d) is satisfied.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present disclosure relates to toners for developing electrostatic images used in electrophotography, electrostatic recording, and the like. [Background technology]

[0002] In recent years, full-color electrophotographic copiers have become widespread and are beginning to be applied to the printing market. In the printing market, there is a growing demand for high speed, high image quality, and high productivity while being compatible with a wide range of media (paper types). For example, even when the paper type is changed from thick paper to thin paper, there is a demand for media uniformity, which means that printing can continue without changing the process speed or the heating temperature setting of the fixing unit to match the paper type. To meet media uniformity, there is a demand for toner that can complete fixing properly over a wide range of fixing temperatures, from low to high. In order to complete fixing over a wide range of fixing temperatures, crystalline polyesters having sharp melting properties are added to the toner to function as plasticizers for the binder resin, thereby improving low-temperature fixing performance, and various studies are being conducted to improve the storage stability of the toner, which is a drawback of the addition of such a plasticizer. For example, Patent Document 1 discloses a toner in which a crystalline polyester resin is mixed with an amorphous polyester resin to improve low-temperature fixing properties and a shell is formed on the toner surface to improve the storage stability of the toner. On the other hand, in the printing market, the image preservation of printed matter is also important. Images formed with toners that have good low-temperature fixing properties may adhere to each other in a high-temperature environment, even if the toner has good preservation properties, because the fixed image is softened. When the adhered printed matter is peeled off, uneven gloss may occur or the image may peel off. Patent Document 2 discloses a toner that improves image storage stability, which deteriorates due to low-temperature fixation, by adjusting the primary particle size, average circularity and average aspect ratio of secondary particles of silica particles contained as an external additive within specific ranges in order to improve both low-temperature fixability and image storage stability. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2016-167029 A [Patent Document 2] JP 2018-045112 A Summary of the Invention [Problem to be solved by the invention]

[0004] The toner described in Patent Document 1 has good toner storage stability, but the image storage stability is insufficient since the image is softened after fixing. Furthermore, the toner described in Patent Document 2 is disclosed to have good image preservation properties at a temperature of 30°C and a humidity of 60% RH. However, when printed materials are transported by car or ship, depending on the location where they are loaded, the temperature may become higher than the outside air temperature, leaving room for improvement in image preservation properties. The present disclosure provides a toner having excellent low-temperature fixing properties and image storage properties. [Means for solving the problem]

[0005] The present invention relates to a toner having toner particles containing a crystalline polyester and silica fine particles on the surfaces of the toner particles, The silica fine particles are surface-treated silica fine particles, The solid of the silica fine particles 29 In the Si-NMR DD / MAS measurement, the Si in the structure represented by the following formula (1) a and the peak PD1 corresponding to a silicon atom represented by the following formula (2): b and the peak PD2 corresponding to a silicon atom represented by the following formula (3): c Peaks P and Q corresponding to silicon atoms represented by the following formula are observed, the area of ​​peak PD1 is SD1, the area of ​​peak PD2 is SD2, and the area of ​​peak PQ is SQ; The silica microparticles solid after washing with hexane29 In the Si-NMR DD / MAS measurement, the Si in the structure represented by the following formula (1) a and the peak PD1w corresponding to a silicon atom represented by the following formula (2): b and the peak PD2w corresponding to the silicon atom represented by the following formula (3): c is observed, the area of ​​the peak PD1w is SD1w, the area of ​​the peak PD2w is SD2w, and the area of ​​the peak PQw is SQw. The SD1 and the SD2 are 1.2≦(SD1+SD2) / SD1≦6.2 Fulfilling Ca calculated from the following formula (a) using the SD1, the SD2, and the SQ, and Cb calculated from the following formula (b) using the SD1w, the SD2w, and the SQw satisfy the following formula (c), Ca = (SD1 + SD2) / SQ × 100 (a) Cb = (SD1w + SD2w) / SQw × 100 (b) (Ca-Cb) / Ca×100≦5.0 (c) When the BET specific surface area of ​​the silica fine particles after washing with hexane is S, the following formula (d) is satisfied: 0.04≦Cb / {(SD1w+SD2w) / SD1w} / S≦0.20 (d) The crystalline polyester relates to a toner characterized in that it contains a monomer having a linear hydrocarbon chain having 8 to 12 carbon atoms.

[0006] [ka]

[0007] [ka]

[0008] [ka] (In formula (1) and formula (2), each R independently represents a hydrogen atom, a methyl group, or an ethyl group.) Effect of the Invention

[0009] According to the present disclosure, a toner having excellent low-temperature fixing property and image storage property can be provided. [Brief description of the drawings]

[0010] [Figure 1] FIG. 2 is an explanatory diagram of a diameter a of a silica fine particle and a portion b where the silica fine particle is buried, which are necessary for calculating the buried ratio of the silica fine particle on the surface of a toner particle. [Diagram 2] FIG. 2 is a schematic diagram of a heat treatment device suitable for performing a surface treatment, with hot air, on toner particles to which silica fine particles are externally added. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] In the present disclosure, the description of a numerical range such as "XX or more and YY or less" or "XX to YY" means a numerical range including the lower and upper limits, which are the endpoints, unless otherwise specified. When a numerical range is described in stages, the upper and lower limits of each numerical range can be arbitrarily combined.

[0012] Further, the toner of the present invention has toner particles and silica fine particles, and the toner particles before the silica fine particles are externally added may be referred to as "toner base particles".

[0013] [Features of the present invention] As a result of investigations aimed at further improving low-temperature fixing ability and image storage stability, the present inventors have found that by using the following toner, unprecedentedly excellent low-temperature fixing ability and image storage stability can be obtained.

[0014] That is, the present invention provides a toner having toner particles containing a crystalline polyester and silica fine particles on the surfaces of the toner particles, The silica fine particles are surface-treated silica fine particles, The solid of the silica fine particles 29 In the Si-NMR DD / MAS measurement, the Si in the structure represented by the following formula (1) a and the peak PD1 corresponding to a silicon atom represented by the following formula (2): b and the peak PD2 corresponding to a silicon atom represented by the following formula (3): c Peaks P and Q corresponding to silicon atoms represented by the following formula are observed, the area of ​​peak PD1 is SD1, the area of ​​peak PD2 is SD2, and the area of ​​peak PQ is SQ; The silica microparticles solid after washing with hexane 29 In the Si-NMR DD / MAS measurement, the Si in the structure represented by the following formula (1) a and the peak PD1w corresponding to a silicon atom represented by the following formula (2): b and the peak PD2w corresponding to the silicon atom represented by the following formula (3): c is observed, the area of ​​the peak PD1w is SD1w, the area of ​​the peak PD2w is SD2w, and the area of ​​the peak PQw is SQw. The SD1 and the SD2 are 1.2≦(SD1+SD2) / SD1≦6.2 Fulfilling Ca calculated from the following formula (a) using the SD1, the SD2, and the SQ, and Cb calculated from the following formula (b) using the SD1w, the SD2w, and the SQw satisfy the following formula (c), Ca = (SD1 + SD2) / SQ × 100 (a) Cb = (SD1w + SD2w) / SQw × 100 (b) (Ca-Cb) / Ca×100≦5.0 (c) When the BET specific surface area of ​​the silica fine particles after washing with hexane is S, the following formula (d) is satisfied: 0.04≦Cb / {(SD1w+SD2w) / SD1w} / S≦0.20 (d)

[0015] The crystalline polyester is characterized by containing a monomer having a linear hydrocarbon chain having 8 to 12 carbon atoms.

[0016] [ka]

[0017] [ka]

[0018] [ka] (In formula (1) and formula (2), each R independently represents a hydrogen atom, a methyl group, or an ethyl group.)

[0019] The reason why the effects of the present invention are obtained is believed to be as follows.

[0020] In order to improve image preservation, it is effective to make silica particles exist on the surface of the fixed image as a spacer and prevent the toner resin from contacting each other between the images. In order to enhance the spacer effect of the silica fine particles existing on the image surface, it is possible to increase the amount of silica fine particles added to the toner base particles or to increase the particle size of the silica fine particles. However, the inventors have found that with the above-mentioned measures, it is difficult to fully exert the spacer effect of the silica fine particles on the fixed image surface, because a part of the silica fine particles added to the toner base particles is transferred to the fixing member during fixing.

[0021] The inventors have found that to address this problem, by incorporating a crystalline polyester containing a monomer having a linear hydrocarbon chain with 8 to 12 carbon atoms into the toner base particles and by having a siloxane chain of a specific length having a polar group OR at its end present on the surface of the silica fine particles, the migration of silica particles on the toner surface during fixing is suppressed, the spacer effect of the silica fine particles on the surface of the fixed image is fully exerted, and the image storage stability is improved.

[0022] The mechanism by which this is thought to occur is described in detail below.

[0023] The force that inhibits the silica fine particles from migrating from the toner surface during fixing is considered to be an attractive force due to the interaction between the polar group OR present at the end of the siloxane chain chemically bonded to the surface of the silica base of the silica fine particles and the ester group of the crystalline polyester. Therefore, it is important to increase the frequency of the above interaction. The frequency of the above interaction increases when the distance between the terminal ORs of the multiple siloxane chains present on the surface of the silica fine particles is equal to the distance between the ester groups of the crystalline polyester. The distance between the terminal ORs of the siloxane chains is related to the density of the multiple siloxane chains present on the surface of the silica fine particles, and when the density of the siloxane chains is high, the distance between the terminal ORs becomes small, and when the density of the siloxane chains is low, the distance between the terminal ORs becomes large. In addition, the distance between the terminal ORs of each siloxane chain is also related to the length of the siloxane chain, and when the siloxane chain is long, the distribution of the distance between the terminal ORs of multiple siloxane chains present on the surface of silica fine particles becomes wider, and when the siloxane chain is short, the distribution of the distance between the terminal ORs of multiple siloxane chains present on the surface of silica fine particles becomes narrower.In addition, the affinity between multiple siloxane chains present on the surface of silica fine particles and the linear hydrocarbon chain of crystalline polyester also increases the frequency of the above-mentioned interaction.From the viewpoint of increasing the frequency of the appropriate terminal OR distance, it is considered that the shorter the siloxane chain, the more preferable it is, but from the viewpoint of increasing the affinity with the linear hydrocarbon chain of the above-mentioned crystalline polyester, the average length of the siloxane chain needs to be within a certain appropriate range.

[0024] In other words, in order to increase the frequency of interaction between the polar group OR present at the end of the siloxane chain chemically bonded to the surface of the silica base of the silica microparticles and the ester group of the crystalline polyester, which is intended to prevent the silica microparticles from migrating from the toner surface during fixing, it is important to keep all three of the following within appropriate ranges: "average length of the siloxane chain," "density of the siloxane chains," and "distance between the ester groups of the crystalline polyester."

[0025] (average length of siloxane chain) The average length of the siloxane chain in the present invention is 29 In the Si-NMR DD / MAS measurement, the Si in the structure represented by the above formula (1) a and the area of ​​the peak corresponding to the silicon atom represented by formula (2) (SD1). b The area of ​​the peak corresponding to the silicon atom (SD2) can be expressed by (SD1+SD2) / SD1. a The silicon atom represented by the formula (2) is a silicon atom having a D1 unit structure. b The silicon atom represented by the formula (I) is a silicon atom having a D2 unit structure.

[0026] That is, the silica fine particles are solid 29 In the Si-NMR DD / MAS measurement, the Si a and the peak (PD1) corresponding to a silicon atom represented by the above formula (2). b A peak (PD2) corresponding to a silicon atom represented by the following formula is observed. When the area of ​​peak PD1 is SD1 and the area of ​​peak PD2 is SD2, (SD1+SD2) / SD1 is 1.2 or more and 6.2 or less. In addition, (SD1+SD2) / SD1 is preferably 1.2 or more and 3.8 or less.

[0027] It is preferable that (SD1+SD2) / SD1 is in the above range because it increases the frequency of interaction between the terminal OR of the siloxane chain and the ester group of the crystalline polyester, suppresses transfer of the silica fine particles to members, and improves image storage stability.

[0028] The value of (SD1+SD2) / SD1 can be adjusted by changing the type of surface treatment agent containing a siloxane bond, or by changing the temperature or time of the surface treatment.

[0029] (Density of siloxane chains) The density (d) of siloxane chains on the surface of the silica fine particles in the present invention is determined based on the solid 29 Using the results of Si-NMR DD / MAS measurement and BET specific surface area measurement, it can be expressed as follows.

[0030] First, solid 29 In the Si-NMR DD / MAS measurement, the Si in the structure represented by the following formula (3) c When the area of ​​the peak (PQ) corresponding to the silicon atom represented by the following formula (a) is defined as SQ, the amount of siloxane chains present (Ca) is calculated using SD1, SD2, and SQ by the following formula (a): Ca = (SD1 + SD2) / SQ × 100 (a)

[0031] [ka]

[0032] In addition, "Si in the structure represented by formula (3) c The "silicon atom represented by the formula (a)" refers to a silicon atom having a Q unit structure, and the above formula (a) means the ratio of the amount of silicon atoms having a D unit structure to the amount of silicon atoms having a Q unit structure. The silicon atoms in the silica microparticle substrate have a Q unit structure, and there are almost no silicon atoms having a D unit structure. Therefore, the silicon atoms having a D unit structure are considered to be derived from the surface treatment agent, and the above ratio represents the amount of siloxane chains derived from the surface treatment.

[0033] Whether the siloxane chains are chemically bonded to the surface of the silica microparticles can be verified by washing the silica microparticles with a solvent (e.g., hexane) and confirming that there is little change in the amount of the above-mentioned treatment agent before and after washing.

[0034] The specific confirmation method is as follows:

[0035] 1.0 g of silica microparticles is weighed into a 50 ml screw tube and 20 ml of normal hexane is added. Then, extraction is performed for 10 minutes with an ultrasonic homogenizer (VP-050 manufactured by TAITEC) at intensity 20 (output 10 W). The obtained extract is separated with a centrifuge, the supernatant is removed, and the normal hexane is removed from the obtained wet sample with an evaporator to obtain silica microparticles after washing with hexane.

[0036] Using silica particles after washing with hexane, 29 Si-NMR DD / MAS measurement was performed to determine the Si in the structure represented by formula (1). a and the area SD1w of the peak PD1w corresponding to the silicon atom represented by formula (2). b and the area SD2w of the peak PD2w corresponding to the silicon atom represented by formula (3). c The area SQw of the peak PQw corresponding to the silicon atom represented by the formula (b) is obtained. Using the obtained areas SD1w, SD2w, and SQw, the amount of siloxane chains present after hexane washing (Cb) is calculated according to the following formula (b). Cb = (SD1w + SD2w) / SQw × 100 (b)

[0037] From the above Ca and Cb and the following formula (c1), the reduction rate ΔC of the amount of siloxane chains present after hexane washing relative to before hexane washing is calculated. ΔC(%)=(Ca-Cb) / Ca×100 (c1) This reduction rate ΔC is considered to be the ratio of the amount of siloxane chains that are not chemically bonded to the surface of the silica fine particles to the amount of siloxane chains present on the surface of the silica fine particle substrate, and in the present invention, it is 5.0% or less. That is, Ca and Cb satisfy the following formula (c). (Ca-Cb) / Ca×100≦5.0 (c)

[0038] Moreover, the decrease rate ΔC is preferably 0.0% or more and 5.0% or less, and more preferably 0.0% or more and 1.0% or less.

[0039] The density (d) of siloxane chains on the surface of silica microparticles is expressed by the following equation using the amount (Cb) of siloxane chains after the above-mentioned hexane washing, (SD1w+SD2w) / SD1w, which indicates the average length of the siloxane chains, and the BET specific surface area S of the silica microparticles. Cb / {(SD1w+SD2w) / SD1w} / S

[0040] In the present invention, the density (d) of siloxane chains is preferably 0.04 or more and 0.20 or less, and more preferably 0.06 or more and 0.12 or less.

[0041] It is preferable that the density of the siloxane chains is within the above range because it increases the frequency of interaction between the terminal OR of the siloxane chain and the ester group of the crystalline polyester, suppresses the transfer of the silica fine particles to members, and improves the image storage stability.

[0042] (Distance between ester groups in crystalline polyester) The distance between ester groups in the crystalline polyester is determined by the number of carbon atoms in the linear hydrocarbon chain of the monomer having a linear hydrocarbon chain, and the number of carbon atoms in the linear hydrocarbon chain of the monomer having a linear hydrocarbon chain that constitutes the crystalline polyester in the present invention is preferably 8 to 12, and more preferably 10.

[0043] It is preferable that the carbon number of the linear hydrocarbon chain of the monomer having a linear hydrocarbon chain that constitutes the crystalline polyester is within the above range, since this increases the frequency of interaction between the terminal OR of the siloxane chain and the ester group of the crystalline polyester, thereby suppressing the transfer of silica microparticles to materials and improving image storage stability.

[0044] When the physical properties of the silica fine particles described above need to be separated from the toner particles, they can be measured after separation by the method described below. In the separation method described below, the separation is performed in an aqueous medium, so that the silicon compound does not dissolve into the medium. As a result, the silica fine particles can be separated from the toner particles while maintaining the physical properties of the silica fine particles before the separation process. Therefore, the values ​​of each physical property measured using the silica fine particles separated from the toner particles are substantially the same as the values ​​of each physical property measured using the silica fine particles before external addition.

[0045] <Solid 29 Si-NMR measurement method> solid 29 Specifically, the Si-NMR measurement conditions are as follows: Equipment: JNM-ECA400 (JEOL RESONANCE) Calibration: TMS (tetramethylsilane) 0 ppm Temperature: room temperature Measurement method: DD / MAS method 29 Si 45° Sample tube: Zirconia 8.0mmφ Sample: Test tube filled with silica particles in powder form Sample rotation speed: 6kHz Relaxation delay: 90 seconds Scan:5640

[0046] In the NMR spectrum obtained by the above-mentioned measurement, the peak corresponding to the siloxane chain appearing around -20 ppm is separated to obtain a peak PD1 corresponding to the silicon atom having the D1 unit structure and a peak PD2 corresponding to the silicon atom having the D2 unit structure, and the peak areas SD1 and SD2 are calculated from each peak. The peak separation is performed as follows.

[0047] (Peak separation method) The NMR spectrum data obtained by the above method is analyzed to perform peak separation. Peak separation may be performed using commercially available software or a program created independently, as long as it is performed according to the procedure described below.

[0048] The positions of peak PD1 and peak PD2 are fixed at −18.2 ppm and −21.0 ppm, respectively, and peak separation processing is performed using a Voigt function.

[0049] <Measurement of BET specific surface area of ​​silica particles> The BET specific surface area of ​​silica microparticles can be determined by a low-temperature gas adsorption method using a dynamic constant pressure method in accordance with the BET method (BET multipoint method). A specific surface area measuring device (product name: Gemini 2375 Ver. 5.0, manufactured by Shimadzu Corporation) is used to adsorb nitrogen gas onto the surface of a sample, and the BET multipoint method is used to measure the BET specific surface area (m 2 / g) can be calculated.

[0050] <Method for separating silica fine particles from toner particles> 20 g of a 10% by weight aqueous solution of "Contaminon N" (a neutral detergent for cleaning precision measuring instruments with a pH of 7 consisting of a nonionic surfactant, an anionic surfactant, and an organic builder) is weighed into a 50 mL vial and mixed with 1 g of toner.

[0051] The mixture is placed in a KM Shaker (model: V.SX) manufactured by Iwaki Sangyo Co., Ltd., and shaken for 30 seconds at a speed of 50. This causes the silica fine particles to migrate from the toner particle surface to the aqueous solution. In the case of a magnetic toner containing a magnetic material, the silica fine particles that have migrated to the supernatant liquid are separated while the toner particles are restrained using a neodymium magnet, and the precipitated toner is dried in a vacuum (40°C / 24 hours) to obtain silica fine particles.

[0052] In the case of non-magnetic toner, the toner and the silica fine particles that have migrated to the supernatant are separated using a centrifuge (H-9R; manufactured by Kokusan Co., Ltd.) (1000 rpm for 5 minutes).

[0053] In addition, when an external additive other than silica fine particles is added to the toner, the silica fine particles can be separated from the other external additives by centrifuging the external additives separated from the toner by the above-mentioned method. Even when multiple types of silica fine particles are added to the toner, they can be separated by centrifuging as long as they have different particle size ranges. For example, separation can be performed using CS120FNX; manufactured by Hitachi Koki Co., Ltd., under conditions of 40,000 rpm and 20 minutes.

[0054] [Silica fine particles] The silica microparticles are considered to have a structure represented by the following formula (4). In the following formula (4), the silicon atom on the far left (Q unit structure) is the silicon of the silica microparticle substrate, and the moieties (D1 unit structure, D2 unit structure) bonded thereto are moieties (siloxane chains) derived from the surface treatment agent chemically bonded to the surface of the silica microparticle substrate. The value of n in formula (4) is not specified, but considering that (SD1+SD2) / SD1 is 1.2 or more and 6.2 or less, it is presumed that n=1, 2, 3, 4, or 5 is the center of the distribution of n values, and the distribution of n values ​​is within the range of about n=0 to 7.

[0055] [ka] (In the formula, each R independently represents a hydrogen atom, a methyl group, or an ethyl group, and n is an integer of 0 or more (preferably 0 to 7).)

[0056] The silica fine particles preferably have a compound having a siloxane structure on the surface thereof. Also, the silica fine particles are preferably obtained by treating the surface of a silica fine particle substrate with a surface treatment agent containing a siloxane bond. That is, the silica fine particles are preferably treated with a surface treatment agent containing a siloxane bond.

[0057] In the present disclosure, when silica fine particles are surface-treated with a surface treatment agent containing a siloxane bond, the part derived from the surface treatment agent is also referred to as the silica fine particles. The silica fine particles before surface treatment are sometimes referred to as the "silica fine particle substrate."

[0058] The surface treatment agent containing siloxane bonds is not particularly limited, and known materials can be used. In order to easily obtain the above physical properties, it is preferable to perform a surface treatment on the silica fine particle substrate.

[0059] Examples of surface treatment agents containing siloxane bonds include silicone oils such as dimethyl silicone oil; silicone oils in which the side chains or ends of dimethyl silicone oils are modified with organic groups, such as methylhydrogen 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, and fluorine-modified silicone oil; and cyclic siloxanes such as hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, and decamethylcyclopentasiloxane.

[0060] The surface treatment agent containing a siloxane bond is preferably a cyclic siloxane. More preferably, it is a cyclic siloxane having up to 10 ring members. The cyclic siloxane may have a substituent in part of the methyl group bonded to the silicon atom. In addition, among the cyclic siloxanes, it is preferable that the cyclic siloxane is at least one selected from the group consisting of hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, and dodecamethylcyclopentasiloxane. From the viewpoint of ease of control of the chain length and ease of purification, it is more preferable to include octamethylcyclotetrasiloxane.

[0061] The method of surface treatment of the silica microparticle substrate is not particularly limited, and can be carried out by contacting the silica microparticle substrate with a surface treatment agent containing siloxane bonds. From the viewpoint of uniformly treating the surface of the silica microparticle substrate and easily achieving the above-mentioned physical properties, it is preferable to contact the silica microparticle substrate with the surface treatment agent in a dry manner. As described later, examples of the method include a method of contacting the vapor of the surface treatment agent with the silica microparticle substrate, or a method of spraying the undiluted solution of the surface treatment agent or a diluted solution of the surface treatment agent with various solvents and contacting it with the silica microparticle substrate.

[0062] The treatment temperature is not particularly limited since it differs depending on the reactivity of the surface treatment agent used.

[0063] The amount of the surface treatment agent is preferably 40 parts by mass or more and 150 parts by mass or less, more preferably 70 parts by mass or more and 140 parts by mass or less, based on 100 parts by mass of the silica fine particle substrate. In particular, when the surface treatment is performed by contacting cyclic siloxane with steam, it is preferable to add 70 parts by mass or more, more preferably 100 parts by mass or more, based on 100 parts by mass of the silica fine particle substrate. This is preferable because the silica fine particle substrate can be surface-treated more uniformly.

[0064] In addition, within the scope of the present invention, after obtaining silica fine particles by the above-mentioned method, further treatment may be performed using the above-mentioned surface treatment agent containing siloxane bonds. The method of performing the treatment is not particularly limited, and for example, the treatment can be performed by contacting the silica fine particles with the surface treatment agent containing siloxane bonds.

[0065] The silica fine particles have a high hydrophobicity because the hydrogen atoms of the silanol groups of the silica fine particle substrate are replaced with the above-mentioned siloxane chains. The hydrophobicity of the silica fine particles can be estimated by measuring the amount of water adsorbed by the silica fine particles. The silica fine particles have a BET specific surface area of ​​1 m at a temperature of 30°C and a relative humidity of 80%. 2 The amount of water adsorbed per unit is 0.010 cm 3 / m 2 More than 0.100cm 3 / m 2 Preferably, it is less than 0.020 cm 3 / m 2 More than 0.070cm 3 / m 2 More preferably, it is 0.030 cm or less. 3 / m 2 More than 0.060cm 3 / m 2 It is even more preferable that:

[0066] <Method for measuring water adsorption amount> The amount of water adsorption of the silica fine particles is measured by an adsorption equilibrium measuring device (BELSORP-aqua3: manufactured by BEL Japan, Inc.) This device is a device that measures the amount of adsorption of a target gas (water vapor).

[0067] (Degassing) Before measurement, degas the moisture adsorbed in the sample. Attach the cell, filler rod, and cap, and weigh the empty sample. Weigh out 0.3 g of sample and place it in the cell. Place the filler rod in the cell, attach the cap, and attach it to the degassing port. Once all the cells to be measured are attached to the degassing port, open the helium valve. Turn on the button for the port to be degassed, and press the "VAC" button. Continue degassing in this manner for at least one day.

[0068] (measurement) Turn on the power to the main unit (there is a switch on the back of the unit). At the same time, start the vacuum pump. Turn on the power to the main unit for circulating water and the operation panel. Press the "BEL" button in the center of the PC screen. Start "aqua3.exe" (measurement software). Temperature control of the high temperature air chamber: Double-click "SV" in the "TIC1" frame on the "Flow path diagram" window to open the "Temperature setting" window. Enter the temperature (80°C) and click "Set".

[0069] Control of adsorption temperature: Double-click "SV" of "Adsorption temperature" in the "Flow path diagram" window and input the "SV value" (adsorption temperature). Click "Circulation start" and "External temperature control", and click setting.

[0070] Press the "PURGE" button to stop degassing, turn off the port button, remove the sample, attach cap 2, weigh the sample, and then attach the sample to the main body measurement section. On the PC, click "Measurement Conditions" to open the "Measurement Conditions Settings" window. The measurement conditions are as follows:

[0071] Air thermostat temperature: 80.0°C, adsorption temperature: 30.0°C, adsorbate name: H2O, equilibration time: 500 sec, temperature wait: 60 min, saturated vapor pressure: 4.245 kPa, sample tube exhaust speed: normal, chemical adsorption measurement: not performed, initial introduction amount: 0.20 cm 3 (STP)·g -1 , Number of measurement relative pressure ranges: 4

[0072] Select the number of samples to be measured, enter the "measurement data file name" and "sample weight." Start the measurement.

[0073] (analysis) Start the analysis software and perform the analysis to calculate the amount of water adsorption per unit mass (cm) at a relative water vapor pressure of 80%. 3The calculated water adsorption amount per unit mass is divided by the BET specific surface area of ​​the silica fine particles obtained by the method described below to calculate the water adsorption amount per surface area (cm 3 / m 2 ) is required.

[0074] Examples of silica fine particles include silicon compounds, particularly silicon halides, generally silicon chlorides, fumed silica produced by burning purified silicon tetrachloride in an oxyhydrogen flame, wet silica produced from water glass, sol-gel silica particles obtained by a wet method, gel silica particles, aqueous colloidal silica particles, alcoholic silica particles, fused silica particles obtained by a gas phase method, deflagration silica particles, etc. Fumed silica is preferred.

[0075] The silica fine particles are preferably, for example, spherical silica fine particles. The term "spherical" includes a shape that is slightly ellipsoidal or a shape that is slightly chipped, and is generally spherical. The average circularity of the silica fine particles is preferably 0.900 or more and 1.000 or less, and more preferably 0.930 or more and 0.990 or less.

[0076] <Measurement of the average circularity of silica particles> The silica microparticles are photographed using a scanning electron microscope (SEM) at a magnification of 25,000x and a pixel count of 1,280 x 960 (the size of one pixel is approximately 4 nm x 4 nm). The captured images are then analyzed using the image analysis software Image J (available from https: / / imagej.nih.gov / ij / ) to determine the circularity.

[0077] First, the outline of the silica microparticle is extracted and its projected area S and perimeter L are measured.

[0078] Next, the equivalent circle diameter and circularity are calculated using the above area S and perimeter L. The equivalent circle diameter is the diameter of a circle having the same area as the projected area of ​​the particle image, and the circularity is defined as the perimeter of the circle calculated from the equivalent circle diameter divided by the perimeter of the projected particle image, and is calculated using the following formula. Circularity = 2 × (π × S) 1 / 2 / L

[0079] The above circularity is calculated for at least 100 silica fine particles, and the arithmetic mean value is regarded as the average circularity of the silica fine particles.

[0080] As the silica microparticle substrate, which is the silica microparticle before surface treatment, known materials can be used.For example, silicon compounds, particularly silicon halides, generally silicon chlorides, usually purified silicon tetrachloride is burned in oxyhydrogen flame to produce fumed silica, wet silica produced from water glass, sol-gel method silica particles obtained by wet method, gel method silica particles, aqueous colloidal silica particles, alcoholic silica particles, fused silica particles obtained by gas phase method, deflagration method silica particles, etc. are listed.Preferably, fumed silica.

[0081] The number average particle diameter of the primary particles of the silica fine particles is preferably 5 nm or more and 500 nm or less, more preferably 50 nm or more and 300 nm or less, and particularly preferably 50 nm or more and 200 nm or less. This allows the silica fine particles to adequately cover the toner particles. As a result, it is preferable because it is possible to increase the frequency of interaction between the terminal OR of the siloxane chain on the surface of the silica fine particles and the ester group of the crystalline polyester, suppress the transfer of the silica fine particles to members, and improve the image storage stability.

[0082] <Number average particle diameter of silica particles> The toner particles are observed with a scanning electron microscope (SEM) and the number and particle diameter (maximum diameter) of the silica fine particles present on the surface of the toner particles are measured. At this time, it is possible to confirm that the object being measured is silica fine particles by using an energy dispersive X-ray analyzer (EDS) attached to the SEM. The number-average particle diameter is the average value measured for 100 toner particles.

[0083] [Crystalline polyester] The toner particles contain a crystalline polyester containing a monomer having a linear hydrocarbon chain with a carbon number of 8 to 12. As the monomer having a linear hydrocarbon chain with a carbon number of 8 to 12, the following alcohol components can be mentioned (the number C listed indicates the number of carbons in the linear hydrocarbon chain).

[0084] They are 1,8-octanediol (C8), 1,9-nonanediol (C9), 1,10-decanediol (C10), 1,11-undecanediol (C11), and 1,12-dodecanediol (C12).

[0085] Examples of carboxylic acid components include the following (the numbers "C" listed below are the number of carbon atoms in a linear hydrocarbon chain):

[0086] Sebacic acid (C8), 1,9-nonanedicarboxylic acid (C9), 1,10-decanedicarboxylic acid (C10), and 1,12-dodecanedicarboxylic acid (C12).

[0087] In the present invention, the crystalline polyester preferably contains the above-mentioned monomer component having a linear hydrocarbon chain in an amount of 40 mol % or more.

[0088] Examples of the other monomer components contained in the crystalline polyester include the following.

[0089] Examples of the alcohol component include aromatic diols such as ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,13-tridecanediol, 1,14-tetradecanediol, 1,18-octadecanediol, 1,20-icosanediol, polyoxypropylene adducts of 2,2-bis(4-hydroxyphenyl)propane, and alkylene oxide adducts of bisphenol A including polyoxyethylene adducts of 2,2-bis(4-hydroxyphenyl)propane; glycerin, pentaerythritol, and trimethylolpropane.

[0090] Examples of the carboxylic acid component include oxalic acid, succinic acid, glutaric acid, adipic acid, suberic acid, azelaic acid, 1,14-tetradecanedicarboxylic acid, 1,18-octadecanedicarboxylic acid, etc. Further examples include anhydrides of these acids and lower alkyl esters of these acids. Examples of the alkyl group in the lower alkyl esters include methyl, ethyl, propyl, and isopropyl groups.

[0091] Among these combinations of components, from the viewpoint of low-temperature fixability and image storage stability, a crystalline polyester containing 40 mol% or more of 1,10-decanedicarboxylic acid is preferred. More preferably, a crystalline polyester containing 40 mol% or more of 1,10-decanedicarboxylic acid and 40 mol% or more of 1,6-hexanediol is preferred. By using a crystalline polyester with such a composition, compatibility with other binder resins constituting the toner base particles is improved, and the crystalline polyester can be uniformly present within the toner base particles, making it possible to uniformly hold silica fine particles on the image surface, resulting in good image storage stability.

[0092] The weight average molecular weight of crystalline polyester is 1.0×10 4 Above 1.0×10 5 It is preferable that the value is less than 2.0×10 4 Above 5.0×10 4 It is more preferable that:

[0093] The melting point of the crystalline polyester is preferably 60° C. or higher and 85° C. or lower, and more preferably 62° C. or higher and 73° C. or lower.

[0094] When the weight average molecular weight and melting point of the crystalline polyester are within the above ranges, a plasticizing effect on the binder resin is exhibited during fixing, resulting in better low-temperature fixing properties.

[0095] <Measurement of weight average molecular weight of crystalline polyester> The measurement is carried out by gel permeation chromatography (GPC) as follows.

[0096] First, 50 mg of a sample is placed in 5 mL of chloroform and left at 25°C for several hours. After that, the sample is thoroughly shaken to mix well with the chloroform, and then left to stand for another 24 hours or more until no more of the sample remains.

[0097] The resulting solution is then filtered through a solvent-resistant membrane filter "Myshoridisc H-25-5" (manufactured by Tosoh Corporation) with a pore size of 0.5 μm to obtain a sample solution.

[0098] Using this sample solution, measurements are performed under the following conditions. Equipment: High-speed GPC equipment "Labsolutions GPC" (Shimadzu Corporation) Columns: PLgel 5μm MIXED-C 300mm×7.5mm (Agilent Technologies): 2 units, PLgel 5μm Guard 50mm×7.5mm (Agilent Technologies): 1 unit Eluent: Chloroform Flow rate: 1.0mL / min Oven temperature: 45℃ Sample injection volume: 60 μL Detector: RI (refractive index) detector

[0099] The weight average molecular weight (Mw) of the sample is calculated using a molecular weight calibration curve prepared using standard polystyrene resins (product names "TSK Standard Polystyrene F-850, F-450, F-288, F-128, F-80, F-40, F-20, F-10, F-4, F-2, F-1, A-5000, A-2500, A-1000, A-500" manufactured by Tosoh Corporation).

[0100] <Measurement of melting point of crystalline polyester> The melting point of the crystalline polyester is measured by the following method.

[0101] The measurement is carried out using a differential scanning calorimeter (DSC) MDSC-2920 (manufactured by TA Instruments) in accordance with ASTM D3418-82 under the following conditions.

[0102] First, a precisely weighed sample of about 3 mg is used as a measurement sample, which is placed in an aluminum pan, and an empty aluminum pan is used as a reference.

[0103] The measurement temperature range is 30°C to 200°C. The temperature is first raised from 30°C to 200°C at a rate of 10°C / min, and then lowered from 200°C to 30°C at a rate of 10°C / min.

[0104] Thereafter, the temperature is increased again from 30° C. to 200° C. at a rate of 10° C. / min.

[0105] The peak temperature of the maximum endothermic peak in the specific heat change curve obtained during this second heating process is taken as the melting point of the crystalline polyester.

[0106] [Binder Resin] The toner particles may contain a binder resin, and any known binder resin may be used. For example, the binder resin may be the following:

[0107] Styrene-based resins, styrene-based copolymer resins, polyester resins, polyol resins, polyvinyl chloride resins, phenolic resins, natural resin-modified phenolic resins, natural resin-modified maleic acid resins, acrylic resins, methacrylic resins, polyvinyl acetate, silicone resins, polyurethane resins, polyamide resins, furan resins, epoxy resins, xylene resins, polyvinyl butyral, terpene resins, coumarone-indene resins, and petroleum-based resins. Resins that are preferably used include styrene-based copolymer resins, polyester resins, and hybrid resins in which polyester resins and styrene-based copolymer resins are mixed or partially reacted with each other. Preferably, polyester resins are used.

[0108] The components constituting the polyester resin will be described in detail below. The following components may be used singly or in combination depending on the type and application.

[0109] Examples of the divalent carboxylic acid component constituting the polyester resin include the following dicarboxylic acids or derivatives thereof: 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; alkenylsuccinic acids or alkylsuccinic acids having an average carbon number 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.

[0110] The alkyl group in the lower alkyl esters includes a methyl group, an ethyl group, a propyl group, and an isopropyl group.

[0111] On the other hand, examples of the dihydric alcohol component constituting the polyester resin include the following.

[0112] 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, bisphenol and its derivatives represented by formula (I-1): and diols represented by formula (I-2).

[0113] [ka] (In formula (I-1), R is an ethylene group or a propylene group, x and y are each an integer of 0 or more, and the average value of x+y is 0 or more and 10 or less.)

[0114] [ka] (In formula (I-2), R' is an ethylene group or a propylene group, x' and y' are each an integer of 0 or more, and the average value of x'+y' is 0 or more and 10 or less.)

[0115] The components of the polyester resin may contain a trivalent or higher carboxylic acid component and a trivalent or higher alcohol component in addition to the above-mentioned divalent carboxylic acid component and divalent alcohol component.

[0116] The trivalent or higher carboxylic acid component is not particularly limited, but examples thereof include trimellitic acid, trimellitic anhydride, pyromellitic acid, etc. Furthermore, the trivalent or higher alcohol component includes trimethylolpropane, pentaerythritol, glycerin, etc.

[0117] The polyester resin may contain, in addition to the above-mentioned compounds, a monovalent carboxylic acid component and a monovalent alcohol component as constituents.Specific examples of the monovalent carboxylic acid component include palmitic acid, stearic acid, arachidic acid, behenic acid, cerotic acid, heptacosanoic acid, montanic acid, melissic acid, lactoseric acid, tetracontanoic acid, and pentacontanoic acid.

[0118] Examples of the monohydric alcohol component include behenyl alcohol, ceryl alcohol, melissyl alcohol, and tetracontanol.

[0119] Among these combinations of components, from the viewpoint of low-temperature fixing ability and image storage stability, a polyester resin containing 40 mol % or more of a benzenedicarboxylic acid such as phthalic acid, terephthalic acid, isophthalic acid, or phthalic anhydride, and 40 mol % or more of a diol component in which R of a bisphenol derivative represented by formula (I-1) is a propylene group, is preferred.

[0120] By using a polyester resin having such a configuration, the compatibility with the above-mentioned crystalline polyester is improved, and the crystalline polyester can be uniformly present within the toner base particles, and the silica fine particles can be uniformly held on the image surface, resulting in good image storage stability.

[0121] <Method for evaluating compatibility of crystalline polyester in toner> The compatibility of the crystalline polyester can be evaluated by the following method.

[0122] 0.1 g of the toner is pressed at 20 MPa for 1 minute using a powder molding tool with an inner diameter of 8 mm to prepare a toner pellet.

[0123] The infrared absorption spectrum of the toner base particle pellets thus prepared is obtained by the method described below. The toner pellets are then placed on an aluminum sheet heated to 130°C on a hot plate, covered with a 0.05mm thick PFA resin film, and subjected to a heat and pressure treatment at 0.05MPa for 2 minutes. The infrared absorption spectrum of the toner after the heat and pressure treatment is obtained by the method described below.

[0124] In the infrared absorption spectrum obtained, the absorption peak of the carbonyl group of the polyester resin, 1670 cm -1 ~1770cm -1 The maximum peak intensity in the range is Cp, and the absorption peak of the aromatic ring of polyester resin is 1500 cm -1 and 1540cm -1 The maximum value of the absorption intensity of the peak intensity in the range is defined as Bp, the value of Cp / Bp obtained from the infrared absorption spectrum before the heat and pressure treatment is defined as M0, and the value of Cp / Bp obtained from the infrared absorption spectrum after the heat and pressure treatment is defined as M1.

[0125] As an index of compatibility of the crystalline polyester in the toner, ΔM is calculated by the following formula. ΔM = (M1-M0) / M0

[0126] When the compatibility of the crystalline polyester in the toner is low, the crystalline polyester that is phase-separated by heat and pressure treatment migrates to the toner surface, so the value of M1 becomes larger than M0. The higher the compatibility of the crystalline polyester in the toner, the smaller the value of ΔM becomes.

[0127] In the present invention, ΔM is preferably 0.50 or less, more preferably 0.22 or less, and even more preferably 0.10 or less.

[0128] When the value of ΔM is within the above range, the crystalline polyester can be uniformly present within the toner base particles, and the silica fine particles can be uniformly held on the image surface, resulting in good image storage stability.

[0129] (Method of measuring infrared absorption spectrum) Fourier transform infrared spectrometer Spectrum One: PerkinElmer Measurement mode: ATR method Incident angle of infrared light (λ=5μm): 45° ATR crystal: Ge (refractive index: 4.0) Measurement range: 2000cm -1 From 600cm -1 Acquisition wavelength width: 4.00cm -1 Number of times: 16

[0130] The content of the crystalline polyester in the toner is preferably from 1.0 to 12.0 parts by mass, and more preferably from 3.0 to 9.0 parts by mass, based on 100 parts by mass of the binder resin.

[0131] By having the content of the crystalline polyester within the above range, an effective plasticizing effect can be obtained during fixing, improving low-temperature fixing properties, and increasing the frequency of interaction between the terminal OR of the siloxane chain on the surface of the silica fine particles and the ester group of the crystalline polyester, thereby suppressing transfer of the silica fine particles to materials and improving image storage properties, which is preferable.

[0132] [Other components of toner particles] The toner can be used as any of magnetic one-component toner, non-magnetic one-component toner, and non-magnetic two-component toner.

[0133] When used as a magnetic one-component toner, magnetic iron oxide particles are preferably used as a colorant. Examples of magnetic iron oxide particles contained in the magnetic one-component toner include magnetic iron oxides such as magnetite, maghemite, and ferrite, and magnetic iron oxides containing other metal oxides; metals such as Fe, Co, and Ni, or alloys of these metals with metals such as Al, Co, Cu, Pb, Mg, Ni, Sn, Zn, Sb, Be, Bi, Cd, Ca, Mn, Se, Ti, W, and V, and mixtures thereof. The content of the magnetic iron oxide particles is preferably 30 parts by mass or more and 150 parts by mass or less with respect to 100 parts by mass of the binder resin.

[0134] Examples of colorants for use in non-magnetic one-component toners and non-magnetic two-component toners include the following.

[0135] As black pigments, carbon blacks such as furnace black, channel black, acetylene black, thermal black, and lamp black are used, and magnetic powders such as magnetite and ferrite are also used.

[0136] As a colorant suitable for yellow color, a pigment or a dye can be used. Examples of pigments include CI Pigment Yellow 1, 2, 3, 4, 5, 6, 7, 10, 11, 12, 13, 14, 15, 17, 23, 62, 65, 73, 74, 81, 83, 93, 94, 95, 97, 98, 109, 110, 111, 117, 120, 127, 128, 129, 137, 138, 139, 147, 151, 154, 155, 167, 168, 173, 174, 176, 180, 181, 183, 191, and CI Bat Yellow 1, 3, and 20. Examples of dyes include CI Solvent Yellow 19, 44, 77, 79, 81, 82, 93, 98, 103, 104, 112, and 162. These may be used alone or in combination of two or more.

[0137] As a colorant suitable for cyan, a pigment or a dye can be used. Examples of pigments include CI Pigment Blue 1, 7, 15, 15:1, 15:2, 15:3, 15:4, 16, 17, 60, 62, 66, etc., CI Vat Blue 6, and CI Acid Blue 45. Examples of dyes include CI Solvent Blue 25, 36, 60, 70, 93, 95, etc. These can be used alone or in combination of two or more.

[0138] As a colorant suitable for magenta, a pigment or a dye can be used. Pigments include CI Pigment Red 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 21, 22, 23, 30, 31, 32, 37, 38, 39, 40, 41, 48, 48:2, 48:3, 48:4, 49, 50, 51, 52, 53, 54, 55, 57, 57;1, 58, 60, 63, 64, 68, 81, 81;1, 83, 87, 88, 89, 90, 112, 114, 122, 123, 144, 146, 150, 163, 166, 169, 177, 184, 185, 202, 206, 207, 209, 220, 221, 238, 254, etc.; CI Pigment Violet 19; CI Bat Red 1, 2, 10, 13, 15, 23, 29, 35.

[0139] Examples of dyes for magenta include oil-soluble dyes such as CI Solvent Red 1, 3, 8, 23, 24, 25, 27, 30, 49, 52, 58, 63, 81, 82, 83, 84, 100, 109, 111, 121, 122, CI Disperse Red 9, CI Solvent Violet 8, 13, 14, 21, 27, CI Disperse Violet 1, and basic dyes such as CI Basic Red 1, 2, 9, 12, 13, 14, 15, 17, 18, 22, 23, 24, 27, 29, 32, 34, 35, 36, 37, 38, 39, 40, CI Basic Violet 1, 3, 7, 10, 14, 15, 21, 25, 26, 27, 28. These dyes can be used alone or in combination of two or more.

[0140] The content of the colorant is preferably 1 part by mass or more and 20 parts by mass or less with respect to 100 parts by mass of the binder resin.

[0141] A release agent (wax) may be used to impart releasability to the toner.

[0142] Examples of waxes include the following: aliphatic hydrocarbon waxes such as low molecular weight polyethylene, low molecular weight polypropylene, olefin copolymers, microcrystalline wax, paraffin wax, and Fischer-Tropsch wax; oxidized waxes of aliphatic hydrocarbon waxes such as oxidized polyethylene wax; waxes mainly composed of fatty acid esters such as carnauba wax, behenyl behenate, and montan acid ester wax; and waxes in which fatty acid esters have been partially or completely deoxidized, such as deoxidized carnauba wax.

[0143] In addition, saturated straight-chain fatty acids such as palmitic acid, stearic acid, and montanic acid; unsaturated fatty acids such as brassidic acid, eleostearic acid, and valinaric acid; saturated alcohols such as stearyl alcohol, aralkyl alcohol, behenyl alcohol, carnaubyl alcohol, ceryl alcohol, and melissyl alcohol; polyhydric alcohols such as sorbitol; fatty acid amides such as linoleic acid amide, oleic acid amide, and lauric acid amide; saturated fatty acid bisamides such as methylene bisstearic acid amide, ethylene biscapric acid amide, ethylene bislauric acid amide, and hexamethylene bisstearic acid amide; ethylene bisoleic acid amide, hexamethylene bisoleic acid amide, N,N Examples of such compounds include unsaturated fatty acid amides such as N,N'-dioleyl adipamide and N,N'-dioleyl sebacic acid amide; aromatic bisamides such as m-xylene bisstearic acid amide and N,N'-distearyl isophthalic acid amide; fatty acid metal salts such as calcium stearate, calcium laurate, zinc stearate, and magnesium stearate (commonly known as metal soaps); waxes grafted onto aliphatic hydrocarbon waxes using vinyl copolymerizable monomers such as styrene and acrylic acid; partial esters of fatty acids and polyhydric alcohols, such as behenic acid monoglyceride; and methyl ester compounds having hydroxy groups obtained by hydrogenating vegetable oils and fats.

[0144] Particularly preferred waxes are aliphatic hydrocarbon waxes. For example, low molecular weight hydrocarbons obtained by radical polymerization of alkylene under high pressure or polymerization with a Ziegler catalyst or a metallocene catalyst under low pressure, Fischer-Tropsch wax synthesized from coal or natural gas, paraffin wax, olefin polymers obtained by pyrolysis of high molecular weight olefin polymers, synthetic hydrocarbon waxes obtained from distillation residues of hydrocarbons obtained by the Arge process from synthesis gas containing carbon monoxide and hydrogen, or synthetic hydrocarbon waxes obtained by hydrogenating these are preferred.

[0145] Further, those obtained by fractionating the hydrocarbon wax using the press sweating method, the solvent method, vacuum distillation, or fractional crystallization are more preferably used. In particular, among paraffin waxes, n-paraffin wax and Fischer-Tropsch wax, which are mainly composed of straight chain components, are preferred from the viewpoint of molecular weight distribution.

[0146] These waxes may be used alone or in combination of two or more kinds. The wax is preferably added in an amount of 1 part by mass to 20 parts by mass to 100 parts by mass of the binder resin.

[0147] A charge control agent may be used in the toner. A known charge control agent may be used. For example, an azo iron compound, an azo chromium compound, an azo manganese compound, an azo cobalt compound, an azo zirconium compound, a chromium compound of a carboxylic acid derivative, a zinc compound of a carboxylic acid derivative, an aluminum compound of a carboxylic acid derivative, and a zirconium compound of a carboxylic acid derivative may be used. The carboxylic acid derivative is preferably an aromatic hydroxycarboxylic acid. A charge control resin may also be used. One or more types of charge control agents may be used in combination as necessary. It is preferable to use 0.1 parts by mass or more and 10 parts by mass or less of the charge control agent with respect to 100 parts by mass of the binder resin.

[0148] [Magnetic Carrier] The toner may be mixed with a magnetic carrier to be used as a two-component developer. As the magnetic carrier, a magnetic carrier such as a normal ferrite or magnetite or a resin-coated carrier may be used. In addition, a magnetic material-dispersed resin particle in which a magnetic powder is dispersed in a resin component, or a porous magnetic core particle containing a resin in the void portion may be used.

[0149] Examples of the magnetic material component used in the magnetic material-dispersed resin particles include various magnetic iron compound particles such as magnetite particles, maghemite particles, or magnetic iron oxide particles containing at least one selected from silicon oxide, silicon hydroxide, aluminum oxide, and aluminum hydroxide; magnetoplumbite-type ferrite particles containing barium, strontium, or barium-strontium; and spinel-type ferrite particles containing at least one selected from manganese, nickel, zinc, lithium, and magnesium.

[0150] In addition to the magnetic component, non-magnetic inorganic compound particles such as non-magnetic iron oxide particles such as hematite particles, non-magnetic ferric oxide hydrous particles such as goethite particles, titanium oxide particles, silica particles, talc particles, alumina particles, barium sulfate particles, barium carbonate particles, cadmium yellow particles, calcium carbonate particles, and zinc oxide particles may be used in combination with the magnetic iron compound particles.

[0151] The material of the porous magnetic core particles may be magnetite or ferrite. A specific example of ferrite is represented by the following general formula: (M12O) x (M2O) y (Fe2O3) Z (In the above formula, M1 is a monovalent metal, M2 is a divalent metal, and when x+y+z=1.0, x and y are each 0≦(x,y)≦0.8, and z is 0.2 <z<1.0である。)

[0152] In the formula, it is preferable to use at least one metal atom selected from the group consisting of Li, Fe, Mn, Mg, Sr, Cu, Zn, and Ca as M1 and M2, as well as Ni, Co, Ba, Y, V, Bi, In, Ta, Zr, B, Mo, Na, Sn, Ti, Cr, Al, Si, and rare earth elements.

[0153] The magnetic carrier is preferably a resin-coated carrier having magnetic carrier core particles and a resin coating layer on the surface of the magnetic carrier core particles. The resin coating layer, for example, coats the surface of the magnetic carrier core particles. The magnetic carrier core particles are preferably porous magnetic core particles containing a resin in the void portion.

[0154] The resin to be filled into the voids of the porous magnetic core particles may be either a thermoplastic resin or a thermosetting resin.

[0155] Examples of the resin to be filled include the following thermoplastic resins: novolac resin, saturated alkyl polyester resin, polyarylate, polyamide resin, acrylic resin, and the like.

[0156] Examples of the thermosetting resin include phenolic resins, epoxy resins, unsaturated polyester resins, and silicone resins.

[0157] The method for coating the surfaces of the magnetic carrier core particles with a resin is not particularly limited, but includes coating methods using a coating method such as a dipping method, a spraying method, a brush coating method, and a fluidized bed coating method. Among these, the dipping method is preferred.

[0158] The amount of resin coating the surface of the magnetic carrier core particles (amount of resin coating layer) is preferably 0.1 parts by mass or more and 5.0 parts by mass or less per 100 parts by mass of the magnetic carrier core particles in order to control the charge imparting property to the toner.

[0159] Resins used in the resin coating layer include acrylic resins such as acrylic acid ester copolymers and methacrylic acid ester copolymers, styrene-acrylic resins such as styrene-acrylic acid ester copolymers and styrene-methacrylic acid ester copolymers, fluorine-containing resins such as polytetrafluoroethylene, tetrafluoroethylene-hexafluoropropylene copolymers, monochlorotrifluoroethylene polymers and polyvinylidene fluoride, silicone resins, polyester resins, polyamide resins, polyvinyl butyral, aminoacrylate resins, ionomer resins, and polyphenylene sulfide resins.

[0160] These resins can be used alone or in combination of two or more. Acrylic resins are preferred.

[0161] [Silica fine particles] The toner has toner particles and silica fine particles on the surface of the toner particles. The toner can be obtained by externally adding silica fine particles to the toner particles as an external additive. The content of the silica fine particles in the toner is preferably 0.01 parts by mass or more and 10.00 parts by mass or less, more preferably 3.00 parts by mass or more and 8.00 parts by mass or less, and even more preferably 5.00 parts by mass or more and 8.00 parts by mass or less, relative to 100 parts by mass of the toner particles.

[0162] This is preferable because it allows the silica fine particles to cover the toner particles more thoroughly, increases the frequency of interaction between the terminal OR of the siloxane chain on the surface of the silica fine particles and the ester group of the crystalline polyester, suppresses the transfer of the silica fine particles to components, and improves image storage stability.

[0163] The external addition of an external additive such as silica fine particles to the toner particles can be carried out by mixing the toner particles and the external additive with a mixer as described below.

[0164] Examples of mixers include the following: Henschel Mixer (manufactured by Mitsui Mining Co., Ltd.), Super Mixer (manufactured by Kawata Co., Ltd.), Ribocone (manufactured by Okawara Manufacturing Co., Ltd.), Nauta Mixer, Turbulizer, Cyclomix (manufactured by Hosokawa Micron Corporation), Spiral Pin Mixer (manufactured by Pacific Machinery Co., Ltd.), and Loedige Mixer (manufactured by Matsubo Co., Ltd.).

[0165] It is preferable that a part of the silica fine particles is embedded in the surface of the toner particle. In the silica fine particles embedded in the surface of the toner particle, the embedding ratio of the silica fine particles to the toner particle is preferably 5% to 50%, more preferably 5% to 40%, even more preferably 10% to 30%, particularly preferably 12% to 25%, and even more preferably 14% to 20%.

[0166] By setting the embedding rate of the silica microparticles within the above-mentioned range, the frequency of interaction between the terminal OR of the siloxane chain on the surface of the silica microparticles and the ester group of the crystalline polyester is further increased, thereby suppressing the transfer of the silica microparticles to materials and improving the image storage stability, which is preferable.

[0167] <Calculation of the embedding rate of silica particles on the surface of toner particles> First, as a pretreatment, silica particles that are not embedded or have a low embedding rate are separated from the toner. 20 g of a 10% by weight aqueous solution of "Contaminon N" (a neutral detergent for cleaning precision measuring instruments with a pH of 7 consisting of a nonionic surfactant, an anionic surfactant, and an organic builder) is weighed out into a 50 mL vial and mixed with 1 g of toner.

[0168] Set it in a "KM Shaker" (model: V.SX) manufactured by Iwaki Sangyo Co., Ltd., set the speed to 50, and shake for 30 seconds. This causes the non-buried silica fine particles to move from the toner particle surface to the aqueous solution.

[0169] Then, in the case of magnetic toner containing a magnetic material, the toner particles are restrained using a neodymium magnet, the silica microparticles that have migrated to the supernatant liquid are separated, and the precipitated toner particles are dried in a vacuum (40°C / 24 hours) to dry them up and prepare a sample.

[0170] In the case of non-magnetic toner, the toner particles are separated from the silica fine particles that have not been buried in the supernatant liquid using a centrifuge (H-9R; manufactured by Kokusan Co., Ltd.) (1000 rpm for 5 minutes). The remaining toner particles are filtered by suction to collect the powder of the toner particles and dry them.

[0171] The toner particles are fixed to the specimen stage of the electron microscope using carbon tape, and the toner particles are observed under the following conditions: An image is taken at a location where the toner particle surface has a large inclination angle (for example, 70 to 110°, preferably about 90°). Equipment used: Hitachi High-Technologies Corporation SU8220 Acceleration voltage: 2 kV Emission current: 10μA Image acquisition: Secondary electron detector Image magnification: 50000x Number of pixels: 1280 x 960 (the size of one pixel is approximately 2 nm x 2 nm)

[0172] The acquired images are analyzed using the image analysis software Image J (available from https: / / imagej.nih.gov / ij / ). As shown in Figure 1, the silica microparticles are fitted with a perfect circle (a perfect circle is created using [Oval selections] (hold down the shift key while operating to fix the shape as a perfect circle)), and the buried rate is calculated using the following formula from the diameter a of the silica microparticle and the length b of the part where the silica microparticle is buried. Length b is measured on a straight line passing through the top of the buried side in the depth direction and the center of the silica microparticle in the silica microparticle fitted with a perfect circle. Burial rate (%) = length of buried silica particle b / diameter of silica particle a

[0173] The above embedment rate is calculated for at least 100 silica microparticles, and the arithmetic mean value is regarded as the embedment rate of the silica microparticles.

[0174] The embedding rate of the silica fine particles can be controlled, for example, by adjusting the temperature when the toner particles and the silica fine particles are mixed in a mixer as described above. Alternatively, after mixing the toner particles and the silica fine particles, the toner particles are subjected to a surface treatment (embedding treatment of the silica fine particles) and the conditions (temperature of the treatment atmosphere and exhaust air volume of the treatment space) are adjusted to control the embedding rate. The surface treatment is preferably a heat treatment. For example, a method of treating with hot air can be mentioned.

[0175] The surface treatment of toner particles can be performed using the following devices: Hybridization System (manufactured by Nara Machinery Works), Nobilta (manufactured by Hosokawa Micron Corporation), Mechanofusion System (manufactured by Hosokawa Micron Corporation), Faculty (manufactured by Hosokawa Micron Corporation), Innomizer (manufactured by Hosokawa Micron Corporation), Theta Composer (manufactured by Tokuju Manufacturing Co., Ltd.), Mechano Mill (manufactured by Okada Seiko Co., Ltd.), and Meteor Rainbow MR Type (manufactured by Nippon Pneumatic Co., Ltd.).

[0176] After the embedding treatment step of the silica fine particles is performed, the silica fine particles may be further added externally.

[0177] [Toner manufacturing method] The toner is preferably obtained by the following method.

[0178] That is, the method for producing the toner is as follows: obtaining toner particles; providing silica microparticles; a step of externally adding and mixing silica fine particles into the obtained toner particles; A step of heat-treating the toner particles to which the silica fine particles have been externally added; and a step of externally adding and mixing silica fine particles into the heat-treated toner particles; It is preferred that the compound has the formula:

[0179] <Surface treatment of toner particles> Hereinafter, a method of surface-treating toner particles (for example, toner particles to which silica fine particles are externally added) with hot air using the heat treatment apparatus shown in Fig. 2 will be specifically exemplified. In this example, the toner particles are referred to as the object to be treated.

[0180] The material to be treated, supplied at a fixed amount by the material fixed amount supplying means 1, is guided to an introduction pipe 3, which is installed on a vertical line of the material supplying means, by compressed gas adjusted by a compressed gas flow rate adjusting means 2. The material to be treated that passes through the introduction pipe 3 is uniformly dispersed by a conical protruding member 4 provided in the center of the material supplying means, and is guided to eight supply pipes 5 that radiate outward, and then to a processing chamber 6 where heat treatment is carried out.

[0181] At this time, the flow of the workpiece supplied to the processing chamber 6 is regulated by a regulating means 9 for regulating the flow of the workpiece provided in the processing chamber 6. Therefore, the workpiece supplied to the processing chamber 6 is heat-treated while swirling within the processing chamber 6, and then cooled.

[0182] The hot air for heat-treating the supplied object is supplied from hot air supplying means 7, distributed by distribution member 12, and introduced into treatment chamber 6 by swirling member 13 for swirling the hot air in a spiral shape. In terms of configuration, swirling member 13 for swirling the hot air has multiple blades, and the swirling of the hot air can be controlled by the number and angle of the blades (11 indicates the hot air supplying means outlet).

[0183] The hot air supplied into the treatment chamber 6 preferably has a temperature at the outlet of the hot air supplying means 7 of 100°C or more and 300°C or less, and more preferably 130°C or more and 190°C or less. If the temperature at the outlet of the hot air supplying means 7 is within the above range, it is possible to prevent fusion or coalescence of the workpiece due to excessive heating, while keeping the embedding rate of the silica microparticles within a preferred range. The hot air is supplied from the hot air supplying means 7.

[0184] The heat-treated resin particles are then cooled by cold air supplied from cold air supply means 8. The temperature of the cold air supplied from cold air supply means 8 is preferably -20°C or higher and 30°C or lower. If the temperature of the cold air is within the above range, it is possible to efficiently cool the heat-treated object to be treated, and it is believed that fusion or coalescence of the object to be treated is unlikely to occur. In addition, the absolute moisture content of the cold air is 0.5 g / m 3 More than 15.0g / m 3 It is preferable that:

[0185] Next, the cooled workpiece is collected by the collecting means 10 at the bottom end of the processing chamber 6. A blower (not shown) is provided ahead of the collecting means 10, so that the workpiece is transported by suction.

[0186] The powder particle supply port 14 is provided so that the swirling direction of the supplied workpiece and the swirling direction of the hot air are the same, and the recovery means 10 is also provided in a tangential direction on the outer periphery of the treatment chamber 6 so as to maintain the swirling direction of the swirled workpiece. Furthermore, the cold air supplied from the cold air supply means 8 is configured to be supplied horizontally and tangentially from the outer periphery of the apparatus to the circumferential surface inside the treatment chamber.

[0187] The swirling direction of the material to be treated supplied from powder particle supply port 14, the swirling direction of the cold air supplied from cold air supply means 8, and the swirling direction of the hot air supplied from hot air supply means 7 are all the same. Therefore, no turbulence occurs in the treatment chamber, the swirling flow in the device is strengthened, and a strong centrifugal force is applied to the material to be treated before the heat treatment, further improving dispersibility, making it easy to obtain toner particles with fewer coalesced particles.

[0188] <Method of manufacturing toner particles> In the step of obtaining toner particles, the method for producing the toner particles is not particularly limited, and the toner particles can be produced by a known method, such as a pulverization method, an emulsion aggregation method, or a dissolution suspension method.

[0189] (Crushing method) The toner particles produced by the pulverization method are produced, for example, as follows.

[0190] Crystalline polyester, binder resin, colorant, and other additives as required are thoroughly mixed using a mixer such as a Henschel mixer or ball mill. The mixture is melt-kneaded using a thermal kneader such as a twin-screw kneading extruder, a heating roll, a kneader, or an extruder. At this time, wax, magnetic iron oxide particles, and a metal-containing compound can also be added.

[0191] The molten mixture is cooled and solidified, then pulverized and classified to obtain toner particles. At this time, the embedding rate of silica fine particles on the surface of the toner particles can be controlled by adjusting the exhaust temperature during fine pulverization. The toner particles and external additives such as silica fine particles are mixed in a mixer such as a Henschel mixer to obtain the toner.

[0192] Examples of mixers include the following: Henschel Mixer (manufactured by Mitsui Mining Co., Ltd.), Super Mixer (manufactured by Kawata Co., Ltd.), Ribocone (manufactured by Okawara Manufacturing Co., Ltd.), Nauta Mixer, Turbulizer, Cyclomix (manufactured by Hosokawa Micron Corporation), Spiral Pin Mixer (manufactured by Pacific Machinery Co., Ltd.), and Loedige Mixer (manufactured by Matsubo Co., Ltd.).

[0193] Examples of kneading machines include the following: KRC kneader (Kurimoto Iron Works); Buss-Co kneader (Buss); TEM type extruder (Toshiba Machine); TEX twin-screw kneader (Japan Steel Works); PCM kneader (Ikegai Iron Works); three-roll mill, mixing roll mill, kneader (Inoue Seisakusho); Kneadex (Mitsui Mining); MS-type pressure kneader, kneader ruder (Moriyama Seisakusho); Banbury mixer (Kobe Steel, Ltd.).

[0194] Examples of pulverizers include the following: Counter Jet Mill, Micron Jet, Innomizer (manufactured by Hosokawa Micron Corporation); IDS type mill, PJM jet pulverizer (manufactured by Nippon Pneumatic Mfg. Co., Ltd.); Cross Jet Mill (manufactured by Kurimoto Iron Works Co., Ltd.); Urmax (manufactured by Nisso Engineering Co., Ltd.); SK Jet-O-Mill (manufactured by Seishin Enterprise Co., Ltd.); Cryptron (manufactured by Kawasaki Heavy Industries, Ltd.); Turbo Mill (manufactured by Turbo Kogyo Co., Ltd.); and Super Rotor (manufactured by Nisshin Engineering Co., Ltd.).

[0195] Furthermore, if necessary, after grinding, the toner particles can be surface-treated using a Hybridization System (manufactured by Nara Machinery Works), Nobilta (manufactured by Hosokawa Micron Corporation), Mechanofusion System (manufactured by Hosokawa Micron Corporation), Faculty (manufactured by Hosokawa Micron Corporation), Innomizer (manufactured by Hosokawa Micron Corporation), Theta Composer (manufactured by Tokuju Manufacturing Co., Ltd.), Mechano Mill (manufactured by Okada Seiko Co., Ltd.), or Meteor Rainbow MR Type (manufactured by Nippon Pneumatic Co., Ltd.) to control the embedding rate of silica microparticles on the surface of the toner particles.

[0196] Examples of classifiers include the following: Classeal, Micron Classifier, and Spedic Classifier (manufactured by Seishin Enterprise Co., Ltd.); Turbo Classifier (manufactured by Nisshin Engineering Co., Ltd.); Micron Separator, Turboplex (ATP), and TSP Separator (manufactured by Hosokawa Micron Corporation); Elbow Jet (manufactured by Nittetsu Mining Co., Ltd.), Dispersion Separator (manufactured by Nippon Pneumatic Mfg. Co., Ltd.); and YM Microcut (manufactured by Yaskawa Shoji Co., Ltd.).

[0197] Examples of sieving devices used to sift out coarse particles include the following: Ultrasonic (manufactured by Koei Sangyo Co., Ltd.); Resonaseave, Gyroshifter (manufactured by Tokuju Kogyo Co., Ltd.); Vibrasonic System (manufactured by Dalton Co., Ltd.); Soniclean (manufactured by Shinto Kogyo Co., Ltd.); Turbo Screener (manufactured by Turbo Industry Co., Ltd.); Microshifter (manufactured by Makino Sangyo Co., Ltd.); and circular vibrating sieve.

[0198] (Emulsification aggregation method) By the emulsion aggregation method, toner particles are produced, for example, as follows.

[0199] A process for preparing a resin particle dispersion (preparation process): The crystalline polyester and, for example, a polyester resin or a styrene-acrylic resin as a binder resin component are dissolved in an organic solvent to form a uniform solution. Then, a basic compound or a surfactant is added as necessary. An aqueous medium is slowly added to this solution while applying shear force using a homogenizer or the like to form resin particles of the binder resin. Finally, the organic solvent is removed to prepare a resin particle dispersion in which the resin particles are dispersed.

[0200] When preparing the resin microparticle dispersion, the amount of the resin component dissolved in the organic solvent is preferably 10 parts by mass or more and 50 parts by mass or less, and more preferably 30 parts by mass or more and 50 parts by mass or less, per 100 parts by mass of the organic solvent.

[0201] Any organic solvent can be used as long as it can dissolve the resin component, but solvents that have high solubility in olefin resins, such as toluene, xylene, and ethyl acetate, are preferred.

[0202] The surfactant is not particularly limited, and examples thereof include anionic surfactants such as sulfate salts, sulfonates, carboxylates, phosphates, and soaps, cationic surfactants such as amine salts and quaternary ammonium salts, and nonionic surfactants such as polyethylene glycols, alkylphenol ethylene oxide adducts, and polyhydric alcohols.

[0203] Examples of the basic compound include inorganic bases such as sodium hydroxide and potassium hydroxide, and organic bases such as triethylamine, trimethylamine, dimethylaminoethanol, diethylaminoethanol, etc. The basic compound may be used alone or in combination of two or more kinds.

[0204] ·Agglomeration process: The aggregation process is a process in which, for example, a colorant microparticle dispersion, a wax microparticle dispersion, and a silicone oil emulsion are mixed with the above-mentioned resin microparticle dispersion as necessary to prepare a mixed liquid, and then the microparticles contained in the prepared mixed liquid are aggregated to form aggregate particles.

[0205] A suitable example of a method for forming aggregate particles is a method in which an aggregating agent is added to and mixed with the above-mentioned mixed liquid, and the temperature is increased or mechanical power is appropriately applied.

[0206] The colorant particle dispersion is prepared by dispersing the above-mentioned colorant. The colorant particles are dispersed by a known method, and for example, a media type dispersing machine such as a rotary shear type homogenizer, a ball mill, a sand mill, or an attritor, or a high pressure counter collision type dispersing machine is preferably used. In addition, a surfactant or a polymer dispersing agent that provides dispersion stability can be added as necessary.

[0207] Wax microparticle dispersion and silicone oil emulsion are prepared by dispersing each material in aqueous medium. Each material is dispersed by known methods, for example, a media type dispersing machine such as a rotary shear type homogenizer, a ball mill, a sand mill, an attritor, or a high pressure collision type dispersing machine is preferably used. In addition, surfactants or polymer dispersing agents that provide dispersion stability can be added as necessary.

[0208] Examples of the flocculant include metal salts of monovalent metals such as sodium and potassium, metal salts of divalent metals such as calcium and magnesium, metal salts of trivalent metals such as iron and aluminum, and polyvalent metal salts such as polyaluminum chloride. From the viewpoint of particle size controllability in the flocculation step, metal salts of divalent metals such as calcium chloride and magnesium sulfate are preferred.

[0209] The addition and mixing of the flocculant is preferably carried out in a temperature range of room temperature to 75° C. When the mixing is carried out under these temperature conditions, the flocculation proceeds in a stable state. The mixing can be carried out using a known mixing device, homogenizer, mixer, etc.

[0210] ·Fusion process: The fusion step is a step in which the aggregate particles are fused by heating, preferably to a temperature equal to or higher than the melting point of the olefin-based resin, to produce particles having smooth surfaces of the aggregate particles.

[0211] Before entering the fusion step, a chelating agent, a pH adjuster, a surfactant, etc. may be appropriately added in order to prevent fusion between the obtained resin particles.

[0212] Examples of chelating agents include ethylenediaminetetraacetic acid (EDTA) and its alkali metal salts such as the Na salt, sodium gluconate, sodium tartrate, potassium and sodium citrate, nitrilotriacetate (NTA) salts, and many water-soluble polymers containing both COOH and OH functionality (polyelectrolytes).

[0213] The time for the fusion process is short if the heating temperature is high, and long if the heating temperature is low. That is, the time for heat fusion depends on the heating temperature and cannot be generally specified, but is generally about 10 minutes to 10 hours.

[0214] ·Cooling process: This is a step of cooling the temperature of the aqueous medium containing the resin particles obtained in the fusion step. Although not particularly limited, the specific cooling rate is about 0.1 to 50° C. / min.

[0215] Cleaning process: The resin particles produced through the above steps can be repeatedly washed and filtered to remove impurities from the resin particles.

[0216] Specifically, it is preferable to wash the resin particles with an aqueous solution containing a chelating agent such as ethylenediaminetetraacetic acid (EDTA) and its Na salt, and then wash the resin particles with pure water.

[0217] By repeating washing with pure water and filtration several times, metal salts, surfactants, etc. in the resin particles can be removed. The number of filtrations is preferably 3 to 20 times, more preferably 3 to 10 times, from the viewpoint of production efficiency.

[0218] ·Drying and classification process: The washed resin particles are dried and appropriately classified to obtain toner particles.

[0219] (Dissolution suspension method) The toner particles produced by the solution suspension method are produced, for example, as follows.

[0220] In the solution suspension method, a resin composition obtained by dissolving a crystalline polyester and a binder resin component such as a polyester resin or a styrene-acrylic resin in an organic solvent is dispersed in an aqueous medium to granulate particles of the resin composition, and then the organic solvent contained in the particles of the resin composition is removed to produce toner particles.

[0221] The dissolution suspension method can be applied to any resin component that dissolves in an organic solvent, and the shape can be easily controlled by adjusting the conditions during desolvation.

[0222] A specific method for producing a toner using a solution suspension method will be described below, but the method is not limited thereto.

[0223] ·Resin component dissolution process: In the resin component dissolving step, the crystalline polyester and binder resin, and, if necessary, other components such as a colorant, wax and silicone oil are dissolved or dispersed in an organic solvent to prepare a resin composition.

[0224] The organic solvent used may be any solvent capable of dissolving the resin component. Specific examples include toluene, xylene, chloroform, methylene chloride, and ethyl acetate. Toluene and ethyl acetate are preferred because of their ability to promote crystallization of the crystalline resin and ease of solvent removal.

[0225] The amount of the organic solvent used is not limited, but may be an amount that allows the resin composition to be dispersed in a poor medium such as water and has a viscosity that allows granulation. Specifically, the mass ratio of the organic solvent to the resin component and, if necessary, other components such as a colorant, wax, and silicone oil is preferably 10 / 90 to 50 / 50 from the viewpoint of granulation property and production efficiency of toner particles described later.

[0226] On the other hand, the colorant, wax and silicone oil do not need to be dissolved in the organic solvent, and may be dispersed. When the colorant, wax and silicone oil are used in a dispersed state, it is preferable to disperse them using a dispersing machine such as a bead mill.

[0227] ·Granulation process: The granulation step is a step of preparing particles of the resin composition by dispersing the obtained resin composition in an aqueous medium using a dispersant so as to obtain a predetermined toner particle size.

[0228] As the aqueous medium, water is mainly used.

[0229] The aqueous medium preferably contains 1% by mass or more and 30% by mass or less of a monovalent metal salt, which inhibits the organic solvent in the resin composition from diffusing into the aqueous medium, thereby enhancing the crystallinity of the resin component contained in the obtained toner particles.

[0230] As a result, the toner tends to have good blocking resistance and good particle size distribution.

[0231] Examples of monovalent metal salts include sodium chloride, potassium chloride, lithium chloride, and potassium bromide, and among these, sodium chloride and potassium chloride are preferred.

[0232] The mixing ratio (mass ratio) of the aqueous medium to the resin composition is preferably aqueous medium / resin composition=90 / 10 to 50 / 50.

[0233] The dispersant is not particularly limited, but as the organic dispersant, a cationic, anionic or nonionic surfactant is used, with the anionic type being preferred.

[0234] Examples of the dispersing agent include sodium alkylbenzene sulfonate, sodium α-olefin sulfonate, sodium alkylsulfonate, sodium alkyldiphenyl ether disulfonate, etc. On the other hand, examples of the inorganic dispersing agent include tricalcium phosphate, hydroxyapatite, calcium carbonate fine particles, titanium oxide fine particles, silica fine particles, etc.

[0235] Of these, the inorganic dispersant tricalcium phosphate is preferred because it has very little adverse effect on the granulation properties and stability thereof, and further on the properties of the toner obtained.

[0236] The amount of dispersant added is determined according to the particle size of the granulated material, and the particle size decreases as the amount of dispersant added increases. Therefore, the amount of dispersant added varies depending on the desired particle size, but it is preferably used in the range of 0.1% by mass to 15.0% by mass based on the resin composition.

[0237] The preparation of particles of the resin composition in an aqueous medium is preferably carried out under high-speed shearing, and examples of devices for providing high-speed shearing include various high-speed dispersers and ultrasonic dispersers.

[0238] Desolvation process: In the solvent removal step, the organic solvent contained in the particles of the obtained resin composition is removed to produce toner particles. The removal of the organic solvent is preferably carried out while stirring.

[0239] Washing, drying and classification process: After the solvent removal step, a washing and drying step may be carried out in which the toner particles are washed several times with water or the like, and then filtered and dried. When a dispersant that dissolves under acidic conditions, such as tricalcium phosphate, is used as the dispersant, it is preferable to wash with hydrochloric acid or the like and then wash with water. By carrying out the washing, the dispersant used for granulation can be removed. After washing, the toner particles can be obtained by filtering and drying, and then appropriately classifying.

[0240] (Process of adding external additives to toner particles) The obtained toner particles and external additives (fine silica particles and other external additives as required) are mixed in a mixer such as a Henschel mixer to obtain a toner.

[0241] In the step of externally adding and mixing silica fine particles to the obtained toner particles, the silica fine particles may be mixed into the toner particles using a mixer such as a Henschel mixer.

[0242] Next, in the step of heat-treating the toner particles to which the silica fine particles have been externally added, it is preferable to use the toner particles to which the silica fine particles have been externally added as the material to be treated and heat-treat them using the heat treatment device described above.

[0243] In the step of externally adding and mixing silica fine particles with the heat-treated toner particles, the silica fine particles are mixed with the heat-treated toner particles using a mixer such as a Henschel mixer to obtain the toner.

[0244] The weight average particle diameter (D4) of the toner is from 4.0 μm to 15.0 μm, preferably from 4.0 μm to 9.0 μm, and more preferably from 6.0 μm to 8.0 μm.

[0245] This is preferable because it allows the silica fine particles to properly coat the toner particles, increases the frequency of interaction between the terminal OR of the siloxane chain on the surface of the silica fine particles and the ester group of the crystalline polyester, suppresses the transfer of the silica fine particles to components, and improves image storage stability.

[0246] The weight average particle size (D4) of the toner can be adjusted, for example, by classification of the toner particles.

[0247] <Method of measuring weight average particle size (D4) of toner> The weight average particle diameter (D4) of the toner is measured with an effective measurement channel count of 25,000 channels using a precision particle size distribution measuring device equipped with a 100 μm aperture tube and using the narrow hole electrical resistance method, called "Coulter Counter Multisizer3" (registered trademark, manufactured by Beckman Coulter, Inc.), and the accompanying dedicated software, "Beckman Coulter Multisizer 3 Version 3.51" (manufactured by Beckman Coulter, Inc.), for setting measurement conditions and analyzing measurement data. The weight average particle diameter (D4) of the toner is calculated by analyzing the measurement data.

[0248] The electrolyte solution used for the measurement is prepared by dissolving special grade sodium chloride in ion-exchanged water to a concentration of approximately 1% by mass, for example, "ISOTON II" (manufactured by Beckman Coulter).

[0249] Before performing measurements and analysis, the dedicated software is set up as follows.

[0250] In the "Change Standard Measurement Method (SOM) screen" of the dedicated software, set the total count number in the 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" (Beckman Coulter). Press the threshold / noise level measurement button to automatically set the threshold and noise level. In addition, set the current to 1600 μA, the gain to 2, the electrolyte to ISOTON II, and check the aperture tube flush after measurement.

[0251] In the "Pulse to particle size conversion setting screen" of the dedicated software, set the bin interval to logarithmic particle size, the particle size bin to 256 particle size bins, and the particle size range to 2 μm to 60 μm.

[0252] The specific measurement method is as follows. (1) Pour about 200 ml of the electrolyte solution into a 250 ml round-bottom glass beaker made exclusively for the Multisizer 3, set it on the sample stand, and stir the stirrer rod counterclockwise at 24 revolutions per second. Then, remove dirt and air bubbles from inside the aperture tube using the "Aperture Tube Flush" function of the dedicated software. (2) Approximately 30 ml of the above-mentioned aqueous electrolyte solution is placed in a 100 ml flat-bottom glass beaker, and approximately 0.3 ml of a solution prepared by diluting "Contaminon N" (a 10% by weight aqueous solution of a neutral detergent for cleaning precision measuring instruments, consisting of a nonionic surfactant, an anionic surfactant, and an organic builder, with a pH of 7, manufactured by Wako Pure Chemical Industries, Ltd.) three times by weight with ion-exchanged water is added as a dispersant. (3) A predetermined amount of ion-exchanged water is placed in the water tank of an ultrasonic disperser "Ultrasonic Dispersion System Tetora150" (manufactured by Nikkaki Bios Co., Ltd.) that has two oscillators with an oscillation frequency of 50 kHz built in with a phase shift of 180 degrees and an electrical output of 120 W, and approximately 2 ml of the Conaminon N is added to this water tank. (4) The beaker (2) is set in the beaker fixing hole of the ultrasonic disperser, and the ultrasonic disperser is operated. Then, the height position of the beaker is adjusted so that the resonance state of the liquid surface of the electrolyte solution in the beaker is maximized. (5) While the electrolyte solution in the beaker in (4) is irradiated with ultrasonic waves, about 10 mg of toner is added little by little to the electrolyte solution and dispersed. Then, ultrasonic dispersion treatment is continued for another 60 seconds. During ultrasonic dispersion, the water temperature in the water tank is appropriately adjusted to be 10°C or higher and 40°C or lower. (6) The (5) electrolyte solution in which the toner is dispersed is dropped into the (1) round-bottom beaker placed in the sample stand using a pipette to adjust the measurement concentration to about 5%. Then, measurements are continued until the number of particles measured reaches 50,000. (7) The measurement data is analyzed using the dedicated software that comes with the device, and the weight-average particle size (D4) is calculated. Note that when the dedicated software is set to Graph / Volume%, the "Average diameter" on the Analysis / Volume Statistics (Arithmetic Mean) screen is the weight-average particle size (D4).

[0253] [Configuration included in the embodiment of the present invention] The disclosure of this embodiment includes the following configuration. (Configuration 1) A toner having toner particles containing a crystalline polyester and silica fine particles on the surfaces of the toner particles, The silica fine particles are surface-treated silica fine particles, The solid of the silica fine particles 29 In the Si-NMR DD / MAS measurement, the Si a and the peak PD1 corresponding to the silicon atom represented by the above formula (2). b and the peak PD2 corresponding to the silicon atom represented by the above formula (3). c Peaks P and Q corresponding to silicon atoms represented by the following formula are observed, the area of ​​peak PD1 is SD1, the area of ​​peak PD2 is SD2, and the area of ​​peak PQ is SQ; The silica microparticles solid after washing with hexane 29 In the Si-NMR DD / MAS measurement, the Si in the structure represented by the following formula (1) a and the peak PD1w corresponding to a silicon atom represented by the following formula (2): b and the peak PD2w corresponding to the silicon atom represented by the following formula (3): c is observed, the area of ​​the peak PD1w is SD1w, the area of ​​the peak PD2w is SD2w, and the area of ​​the peak PQw is SQw. The SD1 and the SD2 satisfy 1.2≦(SD1+SD2) / SD1≦6.2, Ca calculated from the following formula (a) using the SD1, the SD2, and the SQ, and Cb calculated from the following formula (b) using the SD1w, the SD2w, and the SQw satisfy the following formula (c), Ca = (SD1 + SD2) / SQ × 100 (a) Cb = (SD1w + SD2w) / SQw × 100 (b) (Ca-Cb) / Ca×100≦5.0 (c) When the BET specific surface area of ​​the silica fine particles A after washing with hexane is S, the following formula (d) is satisfied: 0.04≦Cb / {(SD1w+SD2w) / SD1w} / S≦0.20 (d) The crystalline polyester contains a monomer having a linear hydrocarbon chain having 8 to 12 carbon atoms. (Configuration 2) The toner according to Configuration 1, wherein the SD1 and the SD2 satisfy 1.2≦(SD1+SD2) / SD1≦3.8 and 0.06≦Cb / {(SD1w+SD2w) / SD1w}≦0.12. (Configuration 3) The toner according to configuration 1 or 2, wherein the crystalline polyester contains a monomer having a linear hydrocarbon chain having 10 carbon atoms. (Configuration 4) The toner according to any one of Configurations 1 to 3, wherein the toner particles contain a binder resin, and the content of the crystalline polyester is 1.0 part by mass or more and 12.0 parts by mass or less per 100 parts by mass of the binder resin. (Configuration 5) The binder resin is a polyester resin, In the infrared absorption spectrum of the toner, the absorption peak of the carbonyl group is 1670 cm -1 From 1770cm -1 The maximum peak intensity in the range is Cp, and the absorption peak of the aromatic ring is 1500 cm -1 From 1540cm -1 the maximum value of absorption intensity of the peak intensity in the range is Bp, the value of Cp / Bp obtained from the infrared absorption spectrum before the heat and pressure treatment is M0, and the value of Cp / Bp obtained from the infrared absorption spectrum after the heat and pressure treatment is M1, ΔM calculated by the following formula (e) is 0.50 or less. ΔM = (M1-M0) / M0 (e) (Configuration 6) The toner according to any one of Configurations 1 to 5, wherein the number average particle size of the primary particles of the silica fine particles is 5 nm or more and 500 nm or less. (Configuration 7) The silica fine particles have a BET specific surface area of ​​1 m at a temperature of 30° C. and a relative humidity of 80%. 2 The amount of water adsorbed per unit is 0.010 cm 3 / m 2 More than 0.100cm 3 / m 2 The toner according to any one of configurations 1 to 6, which is as follows: (Configuration 8) The toner according to any one of Configurations 1 to 7, wherein the content of the silica fine particles is from 0.01 parts by mass to 10.00 parts by mass per 100 parts by mass of the toner particles. (Configuration 9) The toner according to any one of Configurations 1 to 8, wherein the silica fine particles are partly embedded in the toner particles, and an embedding ratio of the silica fine particles to the toner particles is 5% or more and 50% or less. EXAMPLES

[0254] The basic configuration and features of the present invention have been described above, and the present invention will be specifically described below based on examples. However, the present disclosure is not limited to these. Note that parts and % are based on mass unless otherwise specified.

[0255] <Production Example of Polyester Resin 1> Bisphenol A ethylene oxide (2.2 mole adduct): 100.0 mole parts Terephthalic acid: 95.0 parts by mole Trimellitic anhydride: 5.0 mol parts 100 parts of the monomer constituting the above polyester unit was mixed together with 500 ppm of titanium tetrabutoxide in a 5-liter autoclave.

[0256] A reflux condenser, a moisture separator, an N2 gas inlet tube, a thermometer and a stirrer were attached to the autoclave, and a condensation polymerization reaction was carried out at 230°C while introducing N2 gas into the autoclave. The reaction time was adjusted to obtain the desired softening point, and after the reaction was completed, the resin was removed from the vessel, cooled and pulverized to obtain polyester resin 1. The softening point of polyester resin 1 was 130°C, and the Tg was 59°C.

[0257] The softening point was measured as follows.

[0258] (Softening point measurement) The softening point is measured using a constant load extrusion type capillary rheometer "Flow property evaluation device Flow Tester CFT-500D" (Shimadzu Corporation) according to the manual that comes with the device. With this device, a constant load is applied from above the measurement sample by a piston while the measurement sample filled in a cylinder is heated and melted, and the molten measurement sample is extruded from a die at the bottom of the cylinder, and a flow curve showing the relationship between the piston descent amount and temperature can be obtained.

[0259] The softening point is the "melting temperature in the 1 / 2 method" described in the manual attached to the "flow property evaluation device, flow tester CFT-500D."

[0260] The melting temperature in the 1 / 2 method is calculated as follows.

[0261] First, calculate half the difference between the amount of piston descent Smax when the outflow ends and the amount of piston descent Smin when the outflow starts (this is called X. X=(Smax-Smin) / 2). Then, the temperature on the flow curve when the amount of piston descent on the flow curve is the sum of X and Smin is the melting temperature in the 1 / 2 method.

[0262] The measurement sample is a cylindrical sample of about 8 mm in diameter, compressed at 10 MPa for 60 seconds using a tablet press (e.g., NT-100H, manufactured by NPA Systems Co., Ltd.) at 25°C. The measurement conditions for the CFT-500D are as follows. Test mode: Temperature rise method Starting temperature: 50℃ Achieved temperature: 200℃ Measurement interval: 1.0℃ Heating rate: 4.0℃ / min Piston cross-sectional area: 1.000cm 2 Test load (piston load): 10.0kgf / cm 2 (0.9807MPa) Preheat time: 300 seconds Die hole diameter: 1.0mm Die length: 1.0mm

[0263] (Measurement of glass transition temperature Tg) The glass transition temperature (Tg) of the toner is measured by the following method.

[0264] The measurement is carried out using a differential scanning calorimeter (DSC) MDSC-2920 (manufactured by TA Instruments) in accordance with ASTM D3418-82 under the following conditions.

[0265] First, a precisely weighed sample of about 3 mg is used as a measurement sample, which is placed in an aluminum pan, and an empty aluminum pan is used as a reference.

[0266] The measurement temperature range is 30°C to 200°C. The temperature is first raised from 30°C to 200°C at a rate of 10°C / min, and then lowered from 200°C to 30°C at a rate of 10°C / min.

[0267] Thereafter, the temperature is increased again from 30° C. to 200° C. at a rate of 10° C. / min.

[0268] In the specific heat change curve obtained during this second heating process, the glass transition temperature (Tg) is the temperature at which a line equidistant in the vertical direction from the extended lines of each baseline before and after the specific heat change intersects with the curve of the stepwise change in the glass transition.

[0269] <Production Example of Crystalline Polyester 1> In a reaction vessel equipped with a nitrogen inlet tube, a dehydration tube, a stirrer, and a thermocouple, 100.0 mol parts of 1,10-decanedicarboxylic acid as a carboxylic acid monomer and 100.0 mol parts of 1,6-hexanediol as an alcohol monomer were charged. The temperature was raised to 140°C with stirring, and the mixture was heated to 140°C under a nitrogen atmosphere and reacted for 8 hours while distilling off water under normal pressure.

[0270] Next, 0.57 parts of tin dioctylate was added to 100 parts of the combined carboxylic acid monomer and alcohol monomer, and the mixture was reacted while heating to 200°C at a rate of 10°C / hour. After the reaction was continued for 2 hours after reaching 200°C, the pressure in the reaction vessel was reduced to 5 kPa or less, and the reaction was continued at 200°C while monitoring the molecular weight, to obtain crystalline polyester 1. Crystalline polyester 1 had a melting point of 67°C and a weight average molecular weight of 2.4×10 4 It was.

[0271] <Production Example of Crystalline Polyester 2> Crystalline polyester 2 was obtained in the same manner as in the production example of crystalline polyester 1, except that the alcohol monomer was changed to 1,10-decanediol and the reaction time was changed. The melting point of crystalline polyester 2 was 80° C. and the weight average molecular weight was 2.1×10 4 It was.

[0272] <Production Example of Crystalline Polyester 3> Crystalline polyester 3 was obtained in the same manner as in the production example of crystalline polyester 1, except that the carboxylic acid monomer was changed to 1,12-dodecanedicarboxylic acid, the alcohol monomer was changed to 1,10-decanediol, and the reaction time was changed. The melting point of crystalline polyester 3 was 78° C., and the weight average molecular weight was 2.3×10 4 It was.

[0273] <Production Example of Crystalline Polyester 4> Crystalline polyester 4 was obtained in the same manner as in the production example of crystalline polyester 1, except that 1,18-octadecanedicarboxylic acid was used instead of the carboxylic acid monomer and the reaction time was changed. The linear hydrocarbon chain of the 1,18-octadecanedicarboxylic acid used here had 18 carbon atoms, and the melting point of crystalline polyester 4 was 75° C. and the weight average molecular weight was 2.0×10 4 It was.

[0274] <Production Example of Silica Microparticle 1> 500 g of fumed silica (silica fine particle substrate) having a number-average particle size of 120 nm was placed in a reaction vessel, which was then heated and stirred under a nitrogen purge while the temperature inside the reaction vessel was controlled to 330°C.

[0275] Next, vapor of octamethylcyclotetrasiloxane was supplied as a surface treatment agent into the reaction vessel at 10 g / min for 60 minutes, and then the mixture was heated and stirred for 180 minutes to perform surface treatment of the silica fine particle substrate.

[0276] Thereafter, the reaction vessel was purged with nitrogen to remove unreacted surface treatment agent, thereby obtaining silica fine particles 1. The physical properties of the obtained silica fine particles 1 are shown in Table 1.

[0277] <Production Examples of Silica Microparticles 2 to 8> Fumed silica having a number-average particle diameter as shown in Table 1 was produced in the same manner as for silica microparticles 1, except that the surface treatment agent and treatment conditions were changed as shown in Table 1. The physical properties of the obtained silica microparticles 2 to 8 are shown in Table 1.

[0278] <Production Example of Silica Microparticle 9> 500 g of fumed silica (silica fine particle substrate) having a number-average particle size of 120 nm was placed in a reaction vessel, which was then heated and stirred under a nitrogen purge while the temperature inside the reaction vessel was controlled to 330°C.

[0279] Next, polydimethylsiloxane (dynamic viscosity at 25°C: 50 mm 2 A solution prepared by diluting 50 g of silica nanoparticles (average repeating unit number n=60) with 500 g of hexane was supplied by spraying. The solution was then heated and stirred for 60 minutes to treat the surface of the silica nanoparticle substrate, thereby obtaining silica nanoparticles 9. The physical properties of the obtained silica nanoparticles 9 are shown in Table 1.

[0280] <Production Examples of Silica Microparticles 10 and 11> The silica particles were produced in the same manner as for silica particles 9, except that the surface treatment agent and treatment conditions were changed as shown in Table 1. The physical properties of the obtained silica particles 10 and 11 are shown in Table 1.

[0281] [Table 1]

[0282] In Table 1, "amount of treatment agent (parts)" indicates the number of parts by mass of the surface treatment agent relative to 100 parts by mass of the silica fine particle substrate, "SD1" indicates the area of ​​the peak corresponding to silicon atoms having a D1 unit structure, and "SD2" indicates the area of ​​the peak corresponding to silicon atoms having a D2 unit structure. "Existence density d" indicates the existence density of siloxane chains having OR groups at their ends, and "reduction rate ΔC (%)" indicates the reduction rate of the amount of siloxane chains after hexane washing compared to before hexane washing.

[0283] <Production Example of Toner Base Particle 1> 100 parts polyester resin 1 Crystalline polyester 18 parts Paraffin wax (melting point 90°C) 5 parts CI Pigment Blue 15:3 4 parts The above materials were premixed in a Henschel mixer (product name: FM-10C, manufactured by Nippon Coke Co.), and then melt-kneaded at 160° C. using a twin-screw kneading extruder.

[0284] The resulting kneaded product was cooled, coarsely pulverized in a hammer mill, and then finely pulverized in a turbo mill.

[0285] The resulting finely pulverized product was classified using a multi-division classifier utilizing the Coanda effect to obtain toner base particles 1 having a weight average particle size (D4) of 6.5 μm. The physical properties of the obtained toner base particles 1 are shown in Table 2.

[0286] <Production Examples of Toner Base Particles 2 to 8> Toner base particles 2 to 8 were obtained in the same manner as in the production example of toner base particles 1, except that the type and content of the crystalline polyester were changed as shown in Table 2. The physical properties of the obtained toner base particles 2 to 8 are also shown in Table 2.

[0287] [Table 2]

[0288] <Toner 1 Manufacturing Example> Next, to the obtained toner base particles 1, silica fine particles 1 were externally added as a first external addition treatment as described below. Toner base particles 1:100 parts Silica fine particles 1:4.0 parts The above materials were mixed in a Henschel mixer. The operating conditions of the Henschel mixer were a rotation speed of 4000 rpm, a rotation time of 2 min, and a heating temperature of room temperature.

[0289] Then, the toner particles were subjected to a heat treatment using the surface heat treatment device shown in FIG. 2, so that some of the silica fine particles were embedded in the surface of the toner base particles. The operating conditions of the surface heat treatment device were feed rate=1.0 kg / hr, hot air temperature=180° C., and hot air flow rate=1.4 m 3 / min., cold air temperature E=3℃, cold air flow rate=1.2m 3 / min.

[0290] Next, fine and coarse powders were simultaneously classified and removed using a wind classifier utilizing the Coanda effect ("Elbow Jet Lab EJ-L3", manufactured by Nittetsu Mining Co., Ltd.), toner particles 1 having silica fine particles 1 embedded in the surface were obtained. Silica fine particles 1 and 7 were externally added to the heat-treated toner particles 1 thus obtained as the second external addition treatment, as described below.

[0291] Toner particles with silica particles embedded in the surface: 1: 100 parts Silica microparticles 1: 2.4 parts Silica microparticles 7: 1.0 parts The above materials were mixed in a Henschel mixer (product name: FM-10C, manufactured by Nippon Coke Co., Ltd.) at a rotation speed of 67 s -1 After mixing at room temperature at a rotation speed of 4000 rpm for 2 minutes, the mixture was passed through an ultrasonic vibration sieve with a mesh size of 54 μm to obtain Toner 1. The embedding rate of the silica fine particles in the obtained toner is shown in Table 3.

[0292] <Production Examples of Toners 2 to 22> Toners 2 to 22 were obtained in the same manner as in the production example of Toner 1, except that the type of toner base particles, the type and content of silica fine particles, and the toner surface treatment temperature were changed as shown in Table 3.

[0293] [Table 3]

[0294] <Magnetic Carrier 1 Manufacturing Example> (Production of Magnetic Carrier Core Particles 1) Process 1 (weighing and mixing process): Fe2O368.3% by mass MnCO328.5% by mass Mg(OH)22.0% by mass SrCO31.2% by mass The above ferrite raw material was weighed, 80 parts of the ferrite raw material was mixed with 20 parts of water, and then wet-mixed in a ball mill using zirconia having a diameter (φ) of 10 mm for 3 hours to prepare a slurry. The solid content of the slurry was 80 mass %.

[0295] Step 2 (pre-firing step): The mixed slurry was dried using a spray dryer (manufactured by Okawara Kakoki Co., Ltd.) and then fired in a batch-type electric furnace in a nitrogen atmosphere (oxygen concentration 1.0% by volume) at a temperature of 1050° C. for 3.0 hours to produce calcined ferrite.

[0296] Step 3 (Crushing step): The calcined ferrite was crushed to about 0.5 mm using a crusher, and water was added to prepare a slurry. The solid content of the slurry was set to 70 mass %. The slurry was crushed for 3 hours using a wet ball mill with 1 / 8 inch stainless steel beads to obtain a slurry. The slurry was further crushed for 4 hours using a wet bead mill with 1 mm diameter zirconia to obtain a calcined ferrite slurry with a volume-based 50% particle size (D50) of 1.3 μm.

[0297] Process 4 (granulation process): To 100 parts of the calcined ferrite slurry, 1.0 part of ammonium polycarboxylate as a dispersant and 1.5 parts of polyvinyl alcohol as a binder were added, and the mixture was granulated into spherical particles using a spray dryer (manufactured by Okawara Kakoki Co., Ltd.) and dried. The resulting granulated material was subjected to particle size adjustment, and then heated at 700°C for 2 hours using a rotary electric furnace to remove organic substances such as the dispersant and binder.

[0298] Step 5 (firing): The material was fired in a nitrogen atmosphere (oxygen concentration 1.0% by volume) for 2 hours from room temperature to the firing temperature (1100°C), and then held at 1100°C for 4 hours. The material was then cooled to 60°C over 8 hours, returned from the nitrogen atmosphere to the air, and taken out at a temperature of 40°C or less.

[0299] Step 6 (sorting step): After the agglomerated particles were crushed, they were sieved through a sieve with 150 μm openings to remove coarse particles, air classification to remove fine powder, and magnetic separation to remove low magnetic force particles to obtain porous magnetic core particles.

[0300] Process 7 (filling process): 100 parts of porous magnetic core particles 1 were placed in a stirring vessel of a mixer (Dalton's universal stirrer NDMV type), the temperature was kept at 60°C, and 5 parts of a filling resin consisting of 95.0 mass% methyl silicone oligomer and 5.0 mass% γ-aminopropyltrimethoxysilane was added dropwise at normal pressure.

[0301] After the dropwise addition was completed, stirring was continued while adjusting the time, and the temperature was raised to 70° C., thereby filling the inside of each porous magnetic core particle with the resin composition.

[0302] After cooling, the resin-filled magnetic core particles obtained were transferred to a mixer (a UD-AT drum mixer manufactured by Sugiyama Heavy Industries Co., Ltd.) equipped with a spiral blade in a rotatable mixing vessel, and the temperature was raised to 140°C at a rate of 2°C / min under a nitrogen atmosphere while stirring. Heating and stirring were then continued at 140°C for 50 minutes.

[0303] After that, the mixture was cooled to room temperature, and the ferrite particles filled with the resin and hardened were taken out, and non-magnetic materials were removed using a magnetic separator. Furthermore, coarse particles were removed using a vibrating sieve to obtain magnetic carrier core particles 1 filled with the resin.

[0304] (Manufacturing of coating resins) Methyl methacrylate monomer 35.4% by mass Toluene 31.3% by mass Methyl ethyl ketone 31.3% by mass Azobisisobutyronitrile 2.0% by mass Of the above materials, methyl methacrylate monomer, toluene, and methyl ethyl ketone were placed in a four-necked separable flask equipped with a reflux condenser, a thermometer, a nitrogen inlet tube, and a stirrer. Nitrogen gas was introduced into the separable flask to create a sufficient nitrogen atmosphere, and the flask was then heated to 80°C, azobisisobutyronitrile was added, and the mixture was refluxed for 5 hours to polymerize.

[0305] Hexane was poured into the reaction product to precipitate the copolymer, which was then filtered and dried in vacuum to obtain a resin.

[0306] 30 parts of the resin was dissolved in a mixed solvent of 40 parts of toluene and 30 parts of methyl ethyl ketone to obtain a resin solution (solid content concentration: 30%).

[0307] (Preparation of Coating Resin Solution) ·Resin solution (solid content concentration 30%) 33.3% by mass Toluene 66.4% by mass Carbon black (Regal 330; Cabot Corporation) 0.3% by mass (Number average particle size of primary particles: 25 nm, Nitrogen adsorption specific surface area: 94 m 2 / g, DBP oil absorption: 75ml / 100g) The above materials were placed in a paint shaker and dispersed for 1 hour using zirconia beads having a diameter of 0.5 mm. The resulting dispersion was filtered through a 5.0 μm membrane filter to obtain a coating resin solution.

[0308] (Magnetic carrier manufacturing) The coating resin solution and magnetic carrier core particles were added to a vacuum degassing kneader maintained at room temperature (the amount of the coating resin solution added was 2.5 parts as a resin component per 100 parts of magnetic carrier core particles 1).

[0309] After the addition, the mixture was stirred at a rotation speed of 30 rpm for 15 minutes. After a certain amount of the solvent had evaporated (80%), the mixture was heated to 80°C while mixing under reduced pressure, and the toluene was distilled off over 2 hours, after which the mixture was cooled.

[0310] The obtained magnetic carrier was subjected to magnetic separation to separate out low magnetic particles, which were passed through a sieve with 70 μm openings and then classified with an air classifier to obtain magnetic carrier 1 having a volume distribution standard 50% particle size (D50) of 38.2 μm.

[0311] <Production Example of Two-Component Developer 1> Toner 1 and magnetic carrier 1 were added so that the toner concentration was 8.0% by mass, and mixed for 0.5 s using a V-type mixer (V-10 type: Tokuju Manufacturing Co., Ltd.). -1 The developer was mixed under the conditions of 1000 g for 1 minute and a rotation time of 5 minutes to prepare two-component developer 1.

[0312] <Production Examples of Two-Component Developers 2 to 22> Except for changing the toner as shown in Table 4, the same procedure as in the production example of two-component developer 1 was carried out to obtain two-component developers 2 to 22.

[0313] [Table 4]

[0314] [Examples 1 to 17, Comparative Examples 1 to 5] The two-component developers thus obtained were each used for the following evaluations.

[0315] <Evaluation of low-temperature fixability> As an image forming device, a Canon digital commercial printing printer imageRUNNER ADVANCE C5051 was used, which was modified so that the fixing temperature and process speed could be freely set. A developer was placed in the developer unit in the cyan position of this modified machine, and the DC voltage VDC of the developer carrier, the charging voltage VD of the electrostatic latent image carrier, and the laser power were adjusted so that the amount of toner on the electrostatic latent image carrier or paper was as desired, and the evaluation described below was performed. ·Paper:CS-680(A4:68.0g / m 2 ) (Sold by Canon Marketing Japan Inc.) Toner load on paper: 0.90mg / cm 2 Evaluation image: 10cm from the center of the A4 paper 2 Place the image Fixing test environment: Low temperature and low humidity environment: Temperature 15℃ / Humidity 10%RH (hereinafter referred to as "L / L")

[0316] The process speed was set to 500 mm / sec, and the fixing temperature was adjusted to output a fixed image, and the state of the fixed image was visually evaluated.

[0317] (Evaluation Criteria) A: Fixing is possible in the temperature range below 115℃. B: Fixing is possible in the temperature range of 115°C or higher and less than 120°C. C: Fixing is possible in the temperature range of 120°C or higher and less than 125°C. D: Fixing is possible in the temperature range of 125°C or higher and less than 130°C. E: Fixable only in the temperature range of 130° C. or higher.

[0318] <Evaluation of image preservation> The optimum fixing temperature is set to 20°C higher than the lowest fixing temperature. 2 ) (sold by Canon Marketing Japan Inc.), with a toner coverage of 0.90 mg / cm on one side of A4 paper. 2The recording sheets on which the solid images were formed were stacked face to face so that the solid images were in contact with each other, and a vertical load of 100 g / cm was applied. 2 The sample was then left to stand for one day in an environment of 65°C and 50% RH. The two images were then separated and the surface defects of the image due to image adhesion (presence or absence of gloss unevenness) were evaluated. The area ratio where the gloss level had changed (i.e., the area ratio where gloss unevenness existed) was determined by binarizing the image through image processing.

[0319] (Evaluation Criteria) A: There are no image defects. B: Uneven gloss of the image occurs. (Gloss change area ratio is less than 2%) C: Image gloss unevenness occurs. (Gloss change area ratio is 2% or more but less than 5%) D: Uneven gloss of the image occurs. (The area ratio where gloss has changed is 5% or more but less than 10%) E: The image peels off.

[0320] The results of the above evaluations are shown in Table 5. In each of the above evaluation items, those that did not receive an E rating were judged to be good.

[0321] [Table 5] In the table, D4 ​​indicates the weight average particle diameter D4 (μm) of the toner.

Claims

1. A toner having toner particles containing a crystalline polyester and silica fine particles on the surfaces of the toner particles, The silica fine particles are surface-treated silica fine particles, The solid of the silica fine particles 29 In the Si-NMR DD / MAS measurement, Si in the structure represented by the following formula (1) a and a peak PD1 corresponding to a silicon atom represented by the following formula (2): b and a peak PD2 corresponding to a silicon atom represented by the following formula (3): c and a peak PQ corresponding to a silicon atom represented by the formula: The silica fine particle solid after washing with hexane 29 In the Si-NMR DD / MAS measurement, Si in the structure represented by the following formula (1) a and the peak PD1w corresponding to the silicon atom represented by the following formula (2): b and the peak PD2w corresponding to the silicon atom represented by the following formula (3): c and a peak PQw corresponding to a silicon atom represented by the formula: The SD1 and the SD2 satisfy 1.2≦(SD1+SD2) / SD1≦6.2, Ca calculated from the following formula (a) using the SD1, SD2, and SQ, and Cb calculated from the following formula (b) using the SD1w, SD2w, and SQw satisfy the following formula (c), Ca=(SD1+SD2) / SQ×100 (a) Cb=(SD1w+SD2w) / SQw×100 (b) (Ca-Cb) / Ca×100≦5.0 (c) When the BET specific surface area of ​​the silica fine particles A after washing with hexane is S, the following formula (d) is satisfied: 0.04≦Cb / {(SD1w+SD2w) / SD1w} / S≦0.20 (d) The crystalline polyester is a polyester synthesized using a monomer having a linear hydrocarbon chain having 8 to 12 carbon atoms. 【Chemical 1】 (In formula (1) and formula (2), each R independently represents a hydrogen atom, a methyl group, or an ethyl group.)

2. 2. The toner according to claim 1, wherein the SD1 and the SD2 satisfy 1.2≦(SD1+SD2) / SD1≦3.8 and 0.06≦Cb / {(SD1w+SD2w) / SD1w}≦0.

12.

3. 3. The toner according to claim 1, wherein the crystalline polyester contains a monomer having a linear hydrocarbon chain having 10 carbon atoms.

4. 3. The toner according to claim 1, wherein the toner particles contain a binder resin, and the content of the crystalline polyester is 1.0 part by mass or more and 12.0 parts by mass or less per 100 parts by mass of the binder resin.

5. the binder resin is a polyester resin, In the infrared absorption spectrum of the toner, the absorption peak of the carbonyl group is 1670 cm -1 From 1770 cm -1 The maximum peak intensity in the range of 1500 cm is taken as Cp, and the absorption peak of the aromatic ring is taken as 1500 cm. -1 From 1540 cm -1 5. The toner according to claim 4, wherein ΔM calculated by the following formula (e) is 0.50 or less, where Bp is the maximum value of absorption intensity of peak intensities in the range, M0 is the value of Cp / Bp obtained from the infrared absorption spectrum before the heat and pressure treatment, and M1 is the value of Cp / Bp obtained from the infrared absorption spectrum after the heat and pressure treatment: ΔM=(M1-M0) / M0 (e)

6. 3. The toner according to claim 1, wherein the number average particle size of the primary particles of the silica fine particles is 5 nm or more and 500 nm or less.

7. The silica fine particles have a BET specific surface area of ​​1 m at a temperature of 30° C. and a relative humidity of 80%. 2 The amount of water adsorbed per unit is 0.010 cm 3 / m 2 More than 0.100cm 3 / m 2 3. The toner according to claim 1, wherein:

8. 3. The toner according to claim 1, wherein the content of the silica fine particles is 0.01 parts by mass or more and 10.00 parts by mass or less with respect to 100 parts by mass of the toner particles.

9. 3. The toner according to claim 1, wherein the silica fine particles are partly embedded in the toner particles, and the embedding ratio of the silica fine particles to the toner particles is 5% or more and 50% or less.

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