Method for manufacturing toner for electrostatic image development

Abstract

This invention relates to a method for producing electrostatic image developing toner that exhibits excellent low-temperature fixing properties and dot reproducibility. [Solution] A method for manufacturing toner for electrostatic image development, comprising the following steps 1 and 2 in this order. Step 1: A process to obtain aggregated particles by agglomerating resin particles containing amorphous polyester resin A and crystalline polyester C in the same or different particles in an aqueous medium containing an internal olefin sulfonate with 14 to 22 carbon atoms. Step 2: A step to obtain fused particles by fusing the obtained aggregated particles.

Description

[Technical Field]

[0001] This invention relates to a method for manufacturing toner for electrostatic image development. [Background technology]

[0002] In the field of electrophotography, the development of electrophotographic systems has led to a demand for the development of electrophotographic toners that can handle higher image quality and higher speeds. To meet the demand for higher image quality and obtain a toner with a narrow particle size distribution, small particle size, and fast fixation that can handle high speeds, so-called chemical toners are manufactured by agglomeration and fusion methods (emulsification agglomeration method, agglomeration and fusion method), in which fine emulsion resin particles are agglomerated and fused in an aqueous medium to obtain toner.

[0003] For example, Patent Document 1 discloses an electrostatic image developing toner that provides excellent low-temperature fixability, blocking resistance, and particle size uniformity, comprising toner particles containing a polyester resin (A) and a colorant, wherein the toner particles are formed by a process including the steps of dispersing resin particles with a volume average particle size of at least 1 μm or less in water and agglomerating the resin particles, and the polyester resin (A) has an acid value of 5 to 50 mg KOH / g, a hydroxyl value of 5 to 50 mg KOH / g, a titanium element content of 20 to 1000 ppm, and a turbidity of 5 or less in a 1 wt% tetrahydrofuran solution. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2010-72476 [Overview of the Initiative] [Problems that the invention aims to solve]

[0005] To accommodate faster printing speeds, a technology is known that incorporates crystalline polyester resin into toner to improve low-temperature fixation. However, it has become clear that there is room to further improve low-temperature fixation by maintaining the uniformity of the crystalline polyester resin within the emulsion particles from the aggregation process to the fusion process in the emulsification aggregation method. Furthermore, while adding a surfactant in the aggregation process can increase the stability of the emulsion particles in an aqueous medium and produce toner with a sharp particle size distribution, obtaining higher-quality printed materials requires toner with an even sharper particle size distribution to improve dot reproduction. The present invention relates to a method for producing electrostatic image developing toner that exhibits excellent low-temperature fixing properties and dot reproducibility. [Means for solving the problem]

[0006] In the aggregation process, using a more hydrophobic surfactant increases the adsorption of the surfactant to the surface of the emulsion particles, thereby improving the stability of the resin particles, i.e., the emulsion particles, in the aqueous medium. As a result, it is expected that the aggregation of emulsion particles will be suppressed, and the aggregation and fusion process will be carried out while maintaining the uniformity of the particle size of each emulsion particle. However, highly hydrophobic surfactants tend to have reduced water solubility, making their use difficult. The inventors have discovered that by using an internal olefin sulfonate having a specific number of carbon atoms as a surfactant, performing an aggregation step followed by a fusion step, a toner for electrostatic image development with excellent low-temperature fixability and dot reproducibility can be obtained. In other words, the present invention relates to the following [1]. [1] A method for manufacturing toner for electrostatic image development, comprising the following steps 1 and 2 in this order. Step 1: A process to obtain aggregated particles by agglomerating resin particles containing amorphous polyester resin A and crystalline polyester C in the same or different particles in an aqueous medium containing an internal olefin sulfonate with 14 to 22 carbon atoms. Step 2: A step to obtain fused particles by fusing the obtained aggregated particles. [Effects of the Invention]

[0007] The present invention provides a method for manufacturing an electrostatic image developing toner that exhibits excellent low-temperature fixing properties and dot reproducibility. [Modes for carrying out the invention]

[0008] [Manufacturing method for toner for electrostatic image development] The present invention's method for manufacturing toner for electrostatic image development (hereinafter also referred to as the "toner manufacturing method") includes the following steps 1 and 2 in this order. Step 1: A process to obtain aggregated particles by agglomerating resin particles containing amorphous polyester resin A and crystalline polyester C in the same or different particles in an aqueous medium containing an internal olefin sulfonate with 14 to 22 carbon atoms. Step 2: A step to obtain fused particles by fusing the obtained aggregated particles. The toner manufacturing method of the present invention makes it possible to obtain a toner for electrostatic image development (hereinafter also simply referred to as "toner") that has excellent low-temperature fixing properties and dot reproducibility. The toner obtained by the toner manufacturing method of the present invention contains toner particles. While the toner particles can be used as is, it is preferable to use toner that has been treated by adding a fluidizing agent or the like as an external additive to the surface of the toner particles.

[0009] The reason why the toner manufacturing method of the present invention can produce toner with excellent low-temperature fixing properties and dot reproducibility is not entirely clear, but it is thought to be as follows. The surfactant used in Step 1 of the method for manufacturing the toner of the present invention exhibits high water solubility by forming a large cyclic hydrophilic part through hydrogen bonding between the sulfo group and the hydroxyl group inside the molecule in an aqueous medium. Also, by fixing two alkyl groups in the same direction, a structure is formed that maintains the hydrophobicity of the alkyl groups in the aqueous medium. Therefore, an alkyl chain with 14 to 22 carbon atoms in the surfactant can enhance the adsorption property to the surface of emulsion particles and improve the stability of the emulsion particles in the aqueous medium. As a result, in Step 1, it becomes possible to suppress excessive aggregation of the same type of emulsion particles, and aggregated particles with relatively uniform particle sizes can be obtained. It is considered that toner particles having a sharp particle size distribution are obtained by fusing the aggregated particles with relatively uniform particle sizes in Step 2, and thus a toner with excellent dot reproducibility is obtained. Also, since the stability of the emulsion particles in the aqueous medium is high, it becomes possible to suppress the aggregation of crystalline polyester resins. Since the crystalline polyester resins do not aggregate excessively with each other even during aggregation, as a result, the dispersibility of the crystalline polyester resin in the toner is maintained. Therefore, it is considered that a toner with excellent low-temperature fixing property is obtained.

[0010] The definitions of various terms in this specification are shown below. Whether a resin is crystalline or amorphous is determined by the crystallinity index. The crystallinity index is defined as the ratio of the softening point of the resin to the maximum peak temperature of endotherm in the measurement method described in the examples below (softening point (°C) / maximum peak temperature of endotherm (°C)). A crystalline resin is one with a crystallinity index of 0.6 or more and 1.4 or less. An amorphous resin is one where no endothermic peak is observed, or if an endothermic peak is observed, the crystallinity index is less than 0.6 or more than 1.4. The crystallinity index can be appropriately adjusted according to the type and ratio of raw material monomers, and manufacturing conditions such as reaction temperature, reaction time, and cooling rate. The carboxylic acid component of the polyester resin includes not only the compound itself, but also anhydrides that decompose during the reaction to generate acids, and alkyl esters of each carboxylic acid (alkyl group having 1 to 3 carbon atoms).

[0011] [Step 1] In Step 1, resin particles containing amorphous polyester resin A and crystalline polyester resin C in the same or different particles are aggregated in an aqueous medium containing an internal olefin sulfonate having 14 to 22 carbon atoms to obtain aggregated particles. The internal olefin sulfonate having 14 to 22 carbon atoms contains a hydroxy form.

[0012] The aqueous medium is a medium mainly composed of water. The water content in the aqueous medium is preferably 70% by mass or more, more preferably 80% by mass or more, still more preferably 90% by mass or more, and 100% by mass or less. Deionized water or distilled water is preferable as the water. As components other than water that can constitute the aqueous medium together with water, organic solvents soluble in water such as alkyl alcohols having 1 to 5 carbon atoms; dialkyl ketones having 3 to 5 carbon atoms such as acetone and methyl ethyl ketone; cyclic ethers such as tetrahydrofuran are used.

[0013] The components contained in the toner particles may be used singly or in combination of two or more. Also, the raw materials of each component contained in the toner particles such as an alcohol component and a carboxylic acid component may be used singly or in combination of two or more.

[0014] <Internal olefin sulfonate having 14 to 22 carbon atoms> In the present invention, internal olefin sulfonates having 14 to 22 carbon atoms (hereinafter also simply referred to as "internal olefin sulfonates") are sulfonates obtained by sulfonating, neutralizing, and hydrolyzing an internal olefin (an olefin having a double bond inside the olefin chain) which is the raw material. That is, when an internal olefin is sulfonated, β-sartone is quantitatively produced, and a portion of the β-sartone is converted into γ-sartone and olefin sulfonic acid, which are further converted into hydroxyalkane sulfonates and olefin sulfonates in the neutralization and hydrolysis process (for example, J. Am. Oil Chem. Soc. 69, 39 (1992)). Note that "internal olefin" is a broad term that also includes cases where a trace amount of so-called α-olefin, in which the double bond is located at position 1 of the carbon chain, is present. Here, the hydroxyl group of the obtained hydroxyalkane sulfonate is inside the alkane chain, and the double bond of the olefin sulfonate is inside the olefin chain. Furthermore, the resulting product is mainly a mixture of these, and may also contain trace amounts of hydroxyalkanesulfonates having a hydroxyl group at the end of the carbon chain, or olefin sulfonates having a double bond at the end of the carbon chain. In this specification, each of these products and their mixtures are collectively referred to as internal olefin sulfonates. Hydroxyalkanesulfonates are also referred to as the hydroxy derivatives of internal olefin sulfonates, and olefin sulfonates are referred to as the olefin derivatives of internal olefin sulfonates. In the present invention, the internal olefin sulfonate contains a hydroxy compound, and may or may not contain an olefin compound.

[0015] The content of the hydroxy compound in the internal olefin sulfonate is preferably 50% by mass or more, more preferably 60% by mass or more, even more preferably 70% by mass or more, even more preferably 75% by mass or more, even more preferably 80% by mass or more, and 100% by mass or less, from the viewpoint of the toner's low-temperature fixability and dot reproducibility.

[0016] In the internal olefin sulfonate, the mass ratio of the hydroxyl compound to the olefin compound (hydroxyl compound / olefin compound) is preferably 50 / 50 or higher, more preferably 60 / 40 or higher, even more preferably 70 / 30 or higher, even more preferably 75 / 25 or higher, and even more preferably 80 / 20 or higher, from the viewpoint of the toner's low-temperature fixability and dot reproducibility. The upper limit of the mass ratio is 100 / 0 or less, and if the internal olefin sulfonate contains an olefin compound, it is less than 100 / 0, and may be 99 / 1 or less.

[0017] The above mass ratio (hydroxyl derivative / olefin derivative) can be measured by the method described in the examples.

[0018] As mentioned above, internal olefin sulfonates are obtained by sulfonating, neutralizing, and hydrolyzing internal olefins. Therefore, unreacted raw material internal olefins and inorganic compounds may remain in the internal olefin sulfonates. It is preferable to have low levels of these components. The content of the raw material internal olefin in the internal olefin sulfonate is preferably 5.0% by mass or less, more preferably 3.0% by mass or less, even more preferably 1.5% by mass or less, even more preferably 1.0% by mass or less, and even more preferably 0.05% by mass or less, from the viewpoint of the toner's low-temperature fixability and dot reproducibility. The content of unreacted olefins within the raw materials can be measured by the method described in the examples.

[0019] From the viewpoint of the toner's low-temperature fixability and dot reproducibility, the content of inorganic compounds in the internal olefin sulfonate is preferably less than 7.5% by mass, more preferably less than 5.0% by mass, even more preferably less than 3.0% by mass, and even more preferably less than 1.0% by mass.

[0020] Here, the inorganic compounds include sulfates and alkaline agents, and the content of these inorganic compounds can be measured by potentiometric titration. Specifically, it can be measured by the method described in the examples.

[0021] The internal olefin sulfonate of the present invention may also contain, as other components, water as a medium, pH adjusters, viscosity reducers, organic solvents, and polyhydric alcohols, in addition to the components mentioned above.

[0022] (Method for producing internal olefin sulfonates) Internal olefin sulfonates can be produced by sulfonating, neutralizing, and hydrolyzing a raw material internal olefin containing a raw material internal olefin with 14 to 22 carbon atoms (hereinafter, the number of carbon atoms may also be similarly described as "C and a number"). More specifically, they can be produced by methods described in, for example, Japanese Patent Publication No. 1633184, Japanese Patent Publication No. 2625150, and Tenside Surf. Det. 31(5)299 (1994).

[0023] As described above, an internal olefin in the raw material refers to an olefin having a double bond inside the olefin chain. From the viewpoint of low-temperature fixability and dot reproducibility of the toner, the content of α-olefins with a double bond at position 1 in the internal olefin in the raw material is preferably less than 2.8% by mass, more preferably 2.6% by mass or less, and from the viewpoint of cost and productivity, preferably 0.01% by mass or more, more preferably 0.1% by mass or more, and even more preferably 0.3% by mass or more.

[0024] The carbon number of the olefin inside the raw material is 14 or more, preferably 16 or more, more preferably 18 or more, and 22 or less, preferably 20 or less, from the viewpoint of the toner's low-temperature fixability and dot reproducibility. The carbon number of the olefin inside the raw material is particularly preferably 18 from the viewpoint of the toner's low-temperature fixability and dot reproducibility. Furthermore, the range of carbon atoms in the hydroxyl and olefinic derivatives is the same as the range of carbon atoms in the olefin within the raw material.

[0025] When obtaining an internal olefin sulfonate by sulfonating, neutralizing, and hydrolyzing a raw material internal olefin, the content of internal olefins in the raw material internal olefins where the double bond is located at the 2-position is preferably 10% by mass or more, more preferably 15% by mass or more, even more preferably 20% by mass or more, and preferably 40% by mass or less, more preferably 35% by mass or less, and even more preferably 30% by mass or less.

[0026] The olefin inside the raw material may contain paraffin components. From the viewpoint of the toner's low-temperature fixability and dot reproducibility, the paraffin component content in the olefin inside the raw material is preferably less than 5% by mass, more preferably less than 3% by mass, even more preferably 1% by mass or less, and even more preferably 0.1% by mass or less.

[0027] The sulfonation reaction can be carried out by reacting 1 mole to 1.2 moles of sulfur trioxide gas with 1 mole of internal olefin in the raw material. The reaction temperature can be between 20°C and 40°C.

[0028] Neutralization is carried out by reacting the sulfonic acid group with an alkaline aqueous solution of sodium hydroxide, potassium hydroxide, ammonia, 2-aminoethanol, etc., in an amount of 1 to 1.5 times the theoretical value of the sulfonic acid group.

[0029] The hydrolysis reaction can be carried out in the presence of water at a temperature between 90°C and 200°C for 30 minutes to 3 hours. These reactions can be carried out continuously. After the reaction is complete, the product can be purified by extraction, washing, etc.

[0030] Furthermore, in producing internal olefin sulfonates, internal olefins having a distribution of 14 to 22 carbon atoms may be used as raw material internal olefins, and the internal olefin sulfonates may be produced by sulfonation, neutralization, and hydrolysis. Alternatively, internal olefin sulfonates may be produced by sulfonation, neutralization, and hydrolysis of a raw material internal olefin having a single number of carbon atoms, and then mixing multiple types of internal olefin sulfonates having different numbers of carbon atoms.

[0031] In the aqueous medium of step 1, the amount of internal olefin sulfonate with 14 to 22 carbon atoms added is, from the viewpoint of low-temperature fixability and dot reproducibility of the toner, 0.1 parts by mass or more, more preferably 0.5 parts by mass or more, even more preferably 1.5 parts by mass or more, even more preferably 2.5 parts by mass or more, and preferably 15 parts by mass or less, more preferably 10 parts by mass or less, even more preferably 6 parts by mass or less, even more preferably 5 parts by mass or less, and even more preferably 3.5 parts by mass or less.

[0032] In the aqueous medium of step 1, the concentration of the internal olefin sulfonate with 14 to 22 carbon atoms is 0.2 g / L or more, more preferably 0.5 g / L or more, even more preferably 1.0 g / L or more, even more preferably 3.0 g / L or more, even more preferably 5.0 g / L or more, and 30.0 g / L or less, more preferably 20.0 g / L or less, even more preferably 15.0 g / L or less, even more preferably 13.0 g / L or less, even more preferably 11.0 g / L or less, and even more preferably 8.0 g / L or less.

[0033] <Amorphous polyester resin A> Amorphous polyester resin A (hereinafter also simply referred to as "resin A") contains a polycondensate of an alcohol component and a carboxylic acid component. The content of the polycondensate of the alcohol component and the carboxylic acid component in resin A is preferably 60% by mass or more, more preferably 80% by mass or more, even more preferably 90% by mass or more, even more preferably 95% by mass or more, and 100% by mass or less, and preferably 100% by mass, from the viewpoint of the toner's low-temperature fixability and dot reproducibility. Resin A may be a modified polyester resin. Examples of modified polyester resins include urethane-modified polyester resins, epoxy-modified polyester resins, and composite resins containing a polyester resin segment and an addition polymerization resin segment.

[0034] Examples of alcohol components include alkylene oxide adducts of aromatic diols, aliphatic diols, alicyclic diols, and polyhydric alcohols of trihydric or higher hydric value. Among these, alkylene oxide adducts of aromatic diols are preferred.

[0035] Examples of alkylene oxide adducts of aromatic diols include those of formula (I):

[0036] [ka] An example of an alkylene oxide adduct of bisphenol A is given by the formula (wherein OR and RO are oxyalkylene groups, R is independently an ethylene or propylene group, x and y represent the average number of moles of alkylene oxide added, each being a positive number, and the sum of x and y is 1 or more, preferably 1.5 or more, 16 or less, preferably 8 or less, and more preferably 4 or less). Examples of alkylene oxide adducts of bisphenol A represented by formula (I) include propylene oxide adducts of 2,2-bis(4-hydroxyphenyl)propane and ethylene oxide adducts of 2,2-bis(4-hydroxyphenyl)propane.

[0037] When the alcohol component contains an alkylene oxide adduct of an aromatic diol, the content of the alkylene oxide adduct of the aromatic diol in the alcohol component is preferably 70 mol% or more, more preferably 80 mol% or more, even more preferably 90 mol% or more, and 100 mol% or less, and preferably 100 mol%, from the viewpoint of the toner's low-temperature fixability and dot reproducibility.

[0038] The aliphatic diol has two or more carbon atoms, preferably 16 or fewer, more preferably 12 or fewer, and even more preferably 8 or fewer. Examples of aliphatic diols include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, 2-methyl-1,3-propanediol, 1,2-pentanediol, 1,3-pentanediol, 1,4-pentanediol, 2,3-pentanediol, 2,4-pentanediol, neopentyl glycol, 2-ethyl-2- Examples include methyl-1,3-propanediol, 2-methyl-1,4-butanediol, 2-ethyl-1,4-butanediol, 2,2-dimethyl-1,4-butanediol, 2,3-dimethyl-1,4-butanediol, 2-methyl-1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, and 1,12-dodecanediol.

[0039] Examples of alicyclic diols include hydrogenated bisphenol A [2,2-bis(4-hydroxycyclohexyl)propane] and alkylene oxide adducts of hydrogenated bisphenol A with 2 to 4 carbon atoms (average number of added moles: 2 to 12).

[0040] Examples of polyhydric alcohols with a valency of 3 or higher include glycerin, pentaerythritol, trimethylolpropane, and sorbitol.

[0041] Examples of carboxylic acid components include aromatic dicarboxylic acids, aliphatic dicarboxylic acids, alicyclic dicarboxylic acids, and trivalent or higher carboxylic acids. Among these, aromatic dicarboxylic acids, aliphatic dicarboxylic acids, and trivalent or higher carboxylic acids are preferred from the viewpoint of low-temperature fixability and dot reproducibility of the toner.

[0042] Examples of aromatic dicarboxylic acids include phthalic acid, isophthalic acid, and terephthalic acid. Among these, isophthalic acid and terephthalic acid are preferred, and terephthalic acid is more preferred. The content of aromatic dicarboxylic acid is preferably 65 mol% or more, more preferably 70 mol% or more, even more preferably 75 mol% or more, and 100 mol% or less, preferably 95 mol% or less, and more preferably 90 mol% or less, from the viewpoint of the toner's low-temperature fixability and dot reproducibility.

[0043] Examples of aliphatic dicarboxylic acids include oxalic acid, malonic acid, maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, adipic acid, succinic acid, and succinic acid which may be substituted with an aliphatic hydrocarbon group having 1 to 20 carbon atoms. Fumaric acid and adipic acid are preferred. Examples of succinic acid substituted with aliphatic hydrocarbon groups having 1 to 20 carbon atoms include octyl succinic acid and dodecenyl succinic acid (tetrapropenyl succinic acid). The aliphatic dicarboxylic acid content is preferably 0.5 mol% or more, more preferably 1 mol% or more, even more preferably 3 mol% or more, and preferably 30 mol% or less, more preferably 25 mol% or less, and even more preferably 20 mol% or less, from the viewpoint of the toner's low-temperature fixability and dot reproducibility.

[0044] Examples of alicyclic dicarboxylic acids include cyclohexanedicarboxylic acid.

[0045] Examples of trivalent or higher carboxylic acids include 1,2,4-benzenetricarboxylic acid (trimellitic acid), 2,5,7-naphthalentricarboxylic acid, and pyromellitic acid. Among these, trimellitic acid is preferred. When the carboxylic acid component contains a trivalent or higher carboxylic acid, the content of the trivalent or higher carboxylic acid in the carboxylic acid component is preferably 1 mol% or more, more preferably 3 mol% or more, even more preferably 5 mol% or more, and preferably 25 mol% or less, more preferably 20 mol% or less, and even more preferably 15 mol% or less, from the viewpoint of the toner's low-temperature fixability and dot reproducibility.

[0046] The alcohol component may contain a monohydric alcohol, and the carboxylic acid component may contain a monohydric carboxylic acid, as appropriate.

[0047] The equivalent ratio [COOH group / OH group] of the carboxyl group of the carboxylic acid component to the hydroxyl group of the alcohol component is preferably 0.7 or higher, more preferably 0.8 or higher, and preferably 1.3 or lower, more preferably 1.2 or lower.

[0048] (Method for producing amorphous polyester resin A) Resin A can be produced, for example, by polycondensation of raw material monomers containing an alcohol component and a carboxylic acid component.

[0049] The polycondensation of the alcohol component and the carboxylic acid component can be carried out, for example, in an inert gas atmosphere, at a temperature of approximately 120°C to 250°C, in the presence of an esterification catalyst, esterification co-catalyst, polymerization inhibitor, etc., as needed. Examples of esterification catalysts include tin compounds such as dibutyltin oxide and tin(II) di(2-ethylhexanoate), and titanium compounds such as titanium diisopropoxybis(triethanolamine). Examples of esterification co-catalysts that can be used together with the esterification catalyst include gallic acid. The amount of esterification catalyst used is preferably 0.01 parts by mass or more and 10 parts by mass or less, based on 100 parts by mass of the total amount of the alcohol component and carboxylic acid component, which are raw material monomers of resin A. The amount of esterification co-catalyst used is preferably 0.001 parts by mass or more and 1 part by mass or less, per 100 parts by mass of the total amount of the alcohol component and the carboxylic acid component. Examples of polymerization inhibitors include radical polymerization inhibitors such as 4-tert-butylcatechol. When a polymerization inhibitor is used, the amount of polymerization inhibitor used is preferably 0.001 parts by mass or more and 1 part by mass or less per 100 parts by mass of the total amount of the alcohol component and the carboxylic acid component.

[0050] (Physical properties of amorphous polyester resin A) The softening point of resin A is preferably 70°C or higher, more preferably 80°C or higher, and even more preferably 90°C or higher, from the viewpoint of heat-resistant storage, and preferably 120°C or lower, more preferably 125°C or lower, and even more preferably 120°C or lower, from the viewpoint of low-temperature fixing properties.

[0051] The glass transition temperature of resin A is preferably 30°C or higher, more preferably 35°C or higher, and even more preferably 40°C or higher, from the viewpoint of heat-resistant storage, and preferably 85°C or lower, more preferably 75°C or lower, and even more preferably 70°C or lower, from the viewpoint of low-temperature fixing properties.

[0052] The acid value of resin A is preferably 5 mg KOH / g or more, more preferably 10 mg KOH / g or more, even more preferably 15 mg KOH / g or more, and preferably 45 mg KOH / g or less, more preferably 35 mg KOH / g or less, and even more preferably 30 mg KOH / g or less.

[0053] The softening point, glass transition temperature, and acid value of resin A can be appropriately adjusted depending on the type and amount of raw material monomer used, as well as manufacturing conditions such as reaction temperature, reaction time, and cooling rate. Furthermore, the softening point, glass transition temperature, and acid value of resin A can be determined by the method described in the examples. Furthermore, when using two or more types of resin A in combination, it is preferable that at least one of them falls within the range of the above-mentioned physical properties. Moreover, it is even more preferable that the softening point, glass transition temperature, and acid value obtained as a mixture thereof are each within the above-mentioned range.

[0054] <Crystalline polyester resin C> Crystalline polyester resin C is, for example, a polycondensate of an alcohol component and a carboxylic acid component. As the alcohol component, α,ω-aliphatic diols are preferred. The number of carbon atoms in the α,ω-aliphatic diol is preferably 2 or more, preferably 16 or less, more preferably 14 or less, and even more preferably 12 or less. Examples of α,ω-aliphatic diols include ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, 1,12-dodecanediol, 1,13-tridecanediol, and 1,14-tetradecanediol. Among these, ethylene glycol and 1,6-hexanediol are preferred from the viewpoint of low-temperature fixability.

[0055] The amount of α,ω-aliphatic diol is preferably 80 mol% or more, more preferably 85 mol% or more, even more preferably 90 mol% or more, even more preferably 95 mol% or more, and 100 mol% or less, and preferably 100 mol%, in the alcohol component.

[0056] The alcohol component may contain other alcohol components other than α,ω-aliphatic diols. Examples of other alcohol components include aliphatic diols other than α,ω-aliphatic diols such as 1,2-propanediol and neopentyl glycol; aromatic diols such as alkylene oxide adducts of bisphenol A; and trivalent or higher alcohols such as glycerin, pentaerythritol, and trimethylolpropane.

[0057] As the carboxylic acid component, aliphatic dicarboxylic acids are preferred, and linear aliphatic dicarboxylic acids are more preferred. The number of carbon atoms in the aliphatic dicarboxylic acid is preferably 4 or more, more preferably 8 or more, even more preferably 10 or more, and preferably 14 or less, more preferably 12 or less. Examples of aliphatic dicarboxylic acids include fumaric acid, sebacic acid, dodecanediic acid, and tetradecanediic acid. Among these, sebacic acid and tetradecanediic acid are preferred from the viewpoint of low-temperature fixation.

[0058] The amount of aliphatic dicarboxylic acid is preferably 80 mol% or more, more preferably 85 mol% or more, even more preferably 90 mol% or more, even more preferably 95 mol% or more, and 100 mol% or less, and preferably 100 mol%, in the carboxylic acid component.

[0059] The carboxylic acid component may contain other carboxylic acid components other than aliphatic dicarboxylic acids. Examples of other carboxylic acid components include aromatic dicarboxylic acids such as terephthalic acid and isophthalic acid; and polycarboxylic acids with a valency of three or more.

[0060] The equivalent ratio [COOH group / OH group] of the carboxyl group of the carboxylic acid component to the hydroxyl group of the alcohol component is preferably 0.7 or higher, more preferably 0.8 or higher, and preferably 1.3 or lower, more preferably 1.2 or lower.

[0061] A method for manufacturing resin C can be similar to that of resin A mentioned above.

[0062] (Physical properties of crystalline polyester resin C) The softening point of resin C is preferably 60°C or higher, more preferably 65°C or higher, and even more preferably 70°C or higher, from the viewpoint of improving the heat resistance of the toner, and preferably 130°C or lower, more preferably 110°C or lower, and even more preferably 95°C or lower, from the viewpoint of further improving low-temperature fixation.

[0063] The melting point of resin C is preferably 50°C or higher, more preferably 55°C or higher, and even more preferably 60°C or higher, from the viewpoint of heat-resistant storage of the toner, and preferably 105°C or lower, more preferably 95°C or lower, and even more preferably 85°C or lower, from the viewpoint of further improving low-temperature fixing performance.

[0064] The acid value of resin C is preferably 5 mg KOH / g or more, more preferably 10 mg KOH / g or more, and more preferably 35 mg KOH / g or less, more preferably 25 mg KOH / g or less, and even more preferably 20 mg KOH / g or less.

[0065] The softening point, melting point, and acid value of resin C can be appropriately adjusted depending on the type and amount of raw material monomer used, as well as manufacturing conditions such as reaction temperature, reaction time, and cooling rate, and can be determined by the method described in the examples below. Furthermore, when using two or more types of resin C in combination, it is preferable that the softening point, melting point, and acid value obtained from the mixture thereof are all within the aforementioned ranges.

[0066] (Resin content, etc.) In the resin particles used in step 1, the mass ratio of resin C to resin A [resin C / resin A] is preferably 1 / 99 or more, more preferably 3 / 97 or more, even more preferably 5 / 95 or more, and preferably 25 / 75 or less, more preferably 20 / 80 or less, and even more preferably 15 / 85 or less.

[0067] The content of resin A in the toner particles is preferably 60% by mass or more, more preferably 65% ​​by mass or more, even more preferably 75% by mass or more, and preferably 98% by mass or less, more preferably 95% by mass or less, and even more preferably 90% by mass or less, from the viewpoint of improving the low-temperature fixability and dot reproducibility of the toner.

[0068] The content of resin C in the toner particles is preferably 1% by mass or more, more preferably 3% by mass or more, even more preferably 5% by mass or more, and preferably 25% by mass or less, more preferably 20% by mass or less, and even more preferably 15% by mass or less, from the viewpoint of the toner's low-temperature fixability and dot reproducibility.

[0069] In the toner particles, the mass ratio of resin C to resin A [resin C / resin A] is preferably 1 / 99 or more, more preferably 3 / 97 or more, even more preferably 5 / 95 or more, and preferably 25 / 75 or less, more preferably 20 / 80 or less, and even more preferably 15 / 85 or less.

[0070] In addition, the toner particles may contain additives such as release agents, colorants, charge control agents, magnetic powders, flow improvers, conductivity modifiers, reinforcing fillers such as fibrous materials, antioxidants, anti-aging agents, and cleaning performance improvers.

[0071] <Release agent> The aggregated particles obtained in step 1 preferably contain a release agent. Examples of release agents include hydrocarbon waxes or oxides thereof such as polypropylene wax, polyethylene wax, ethylene propylene copolymer wax, microcrystalline wax, paraffin wax, and Fischer-Tropsch wax; ester waxes such as carnauba wax, montane wax or their deoxidizing waxes, and fatty acid ester waxes; and fatty acid amides, fatty acids, higher alcohols, and fatty acid metal salts.

[0072] The melting point of the release agent is preferably 60°C or higher, more preferably 70°C or higher, and more preferably 160°C or lower, more preferably 140°C or lower, even more preferably 120°C or lower, and even more preferably 100°C or lower.

[0073] The release agent content in the toner particles is preferably 0.05% by mass or more, more preferably 1% by mass or more, even more preferably 2% by mass or more, and preferably 15% by mass or less, more preferably 10% by mass or less, and even more preferably 5% by mass or less.

[0074] <Coloring agent> The aggregated particles obtained in step 1 preferably contain a coloring agent. As the coloring agent, all dyes, pigments, etc. used as coloring agents for toners can be used. Examples of colorants include carbon black, phthalocyanine blue, permanent brown FG, brilliant first scarlet, pigment green B, rhodamine-B base, solvent red 49, solvent red 146, solvent blue 35, quinacridone, carmine 6B, and disazo yellow. The toner may be either black toner or a color toner other than black.

[0075] The colorant content in the toner particles is preferably 0.05% by mass or more, more preferably 1% by mass or more, even more preferably 2% by mass or more, and preferably 15% by mass or less, more preferably 10% by mass or less, and even more preferably 5% by mass or less.

[0076] <Agglutination> The aggregated particles obtained in the process of agglomerating resin particles include aggregated particles 1, which are obtained by agglomerating resin particles in an aqueous medium containing an internal olefin sulfonate, and aggregated particles 2, which are obtained by using aggregated particles 1 as a core and attaching and agglomerating shell resin particles to this core in an aqueous medium. When simply referred to as "aggregated particles," it means either aggregated particles 1 or 2.

[0077] In the step of agglomerating the resin particles, the resin particles are agglomerated in an aqueous medium containing an internal olefin sulfonate to obtain agglomerated particles 1. In the process of agglomerating the resin particles, it is preferable to further agglomerate the colorant and release agent in addition to the resin particles, and it is preferable to mix the resin particle dispersion, the release agent particle dispersion, and the colorant particle dispersion to agglomerate these particles and obtain agglomerated particles 1.

[0078] (Method for producing resin particle dispersion) The resin particles may be manufactured as a resin particle dispersion containing the same or different resins in the particles. Examples of a "resin particle dispersion containing the same or different resins in the particles" include an aqueous dispersion of resin particles containing amorphous polyester resin A and crystalline polyester resin C, an aqueous dispersion of resin particles containing amorphous polyester resin A, and an aqueous dispersion of resin particles containing crystalline polyester resin C. The dispersion of resin particles in an aqueous medium can be carried out using known methods, but dispersion by phase inversion emulsification is preferred. Examples of phase inversion emulsification methods include adding an aqueous medium to an organic solvent solution of the resin or to molten resin and then emulsifying it. The method of adding an aqueous medium to an organic solvent solution of the resin and then emulsifying it is preferred. The organic solvent used for phase inversion emulsification is not particularly limited as long as it dissolves the resin and is water-soluble, but an example is methyl ethyl ketone. A neutralizing agent may be added to the organic solvent solution of the resin. Examples of neutralizing agents include basic substances. Examples of basic substances include alkali metal hydroxides such as sodium hydroxide and potassium hydroxide; and nitrogen-containing basic substances such as ammonia, trimethylamine, and diethanolamine. Among these, alkali metal hydroxides such as sodium hydroxide and potassium hydroxide are preferred. The degree of neutralization of the resin constituting the resin particles is preferably 35 mol% or more, more preferably 45 mol% or more, even more preferably 55 mol% or more, and preferably 85 mol% or less, more preferably 75 mol% or less, and even more preferably 65 mol% or less. The degree of neutralization of the resin constituting the resin particles can be determined by the following formula. Degree of neutralization (mol%) = [{Amount of neutralizing agent added (g) / Equivalent amount of neutralizing agent} / [{Weighted average acid value of the resin constituting the resin particles (mgKOH / g) × Mass of the resin constituting the resin particles (g)} / (56 × 1000)]] × 100

[0079] While stirring the organic solvent solution of the resin or the molten resin, an aqueous medium is gradually added to cause phase inversion. When adding an aqueous medium, the temperature of the organic solvent solution is preferably above the glass transition temperature of the resin, more preferably above 60°C, even more preferably above 65°C, and preferably below 100°C, more preferably below 95°C, and even more preferably below 90°C, from the viewpoint of improving the dispersion stability of the resin particles containing the resin.

[0080] After phase inversion emulsification, the organic solvent may be removed from the resulting dispersion by distillation or other means, if necessary. Alternatively, the resin particles may be isolated by filtration or other means. It is preferable to use an aqueous dispersion of resin particles from which the organic solvent has been removed after phase inversion emulsification. In this case, the amount of residual organic solvent in the dispersion is preferably 1% by mass or less, more preferably 0.5% by mass or less, and even more preferably substantially 0% by mass.

[0081] Volume-intermediate particle size D of resin particles 50 The particle size is preferably 0.03 μm or larger, more preferably 0.06 μm or larger, even more preferably 0.09 μm or larger, and preferably 1 μm or smaller, more preferably 0.5 μm or smaller, and even more preferably 0.2 μm or smaller. The CV value of the resin particles is preferably 10% or more, more preferably 20% or more, and preferably 40% or less, more preferably 35% or less. Volume-intermediate particle size D of resin particles 50 The CV value is measured by the method described in the examples.

[0082] The solid content concentration of the resin particle dispersion is preferably 5% by mass or more, more preferably 10% by mass or more, even more preferably 15% by mass or more, and preferably 50% by mass or less, more preferably 40% by mass or less, and even more preferably 30% by mass or less, from the viewpoint of improving toner productivity and improving the dispersion stability of the resin particle dispersion.

[0083] (Method for manufacturing a release agent particle dispersion) The mold release agent particle dispersion may be obtained using a surfactant, or by mixing the mold release agent with resin particles. By preparing mold release agent particles using the mold release agent and resin particles, the mold release agent particles are stabilized by the resin constituting the resin particles, making it possible to disperse the mold release agent in an aqueous medium without using a surfactant. In the mold release agent particle dispersion, it is thought that the mold release agent particles have a structure in which many resin particles are attached to the surface. The resin constituting the resin particles that disperse the mold release agent is preferably a polyester resin, and more preferably a composite resin D having a polyester resin segment and an addition polymerization resin segment. For details on the mold release agent particle dispersion and composite resin D, please refer to Japanese Patent Application Publication No. 2024-25642. Alternatively, the aforementioned resin A may be used.

[0084] Release agent particle volume median particle size D 50 From the viewpoint of obtaining uniform aggregated particles 1 by aggregation, the particle size is preferably 0.05 μm or larger, more preferably 0.1 μm or larger, even more preferably 0.15 μm or larger, and preferably 1 μm or smaller, more preferably 0.7 μm or smaller, and even more preferably 0.5 μm or smaller. The CV value of the release agent particles is preferably 20% or more, more preferably 25% or more, and preferably 55% or less, more preferably 50% or less, and even more preferably 45% or less. Release agent particle volume median particle size D 50 The CV value is measured by the method described in the examples.

[0085] (Method for producing a dispersion of coloring agent particles) It is preferable to obtain the colorant particles as a dispersion of colorant particles by dispersing the colorant and an aqueous medium using a disperser such as a homogenizer or an ultrasonic disperser. From the viewpoint of improving the dispersion stability of the colorant, it is preferable to carry out this dispersion in the presence of a surfactant or an addition polymer (hereinafter, the addition polymer used for dispersing the colorant is also referred to as "addition polymer E"). Examples of such surfactants include nonionic surfactants, anionic surfactants, and cationic surfactants. The addition polymer E preferably has structural units derived from addition polymerizable monomer a having an aromatic group, and more preferably further contains at least one selected from the group consisting of addition polymerizable monomer b having an ionic group, addition polymerizable monomer c having a polyalkylene oxide group, and macromonomer d. For a colorant particle dispersion using the addition polymer E, see Japanese Patent Application Publication No. 2024-25642.

[0086] The amount of colorant in the colorant particle dispersion is preferably 1% by mass or more, more preferably 3% by mass or more, even more preferably 5% by mass or more, and preferably 40% by mass or less, more preferably 30% by mass or less, and even more preferably 20% by mass or less, from the viewpoint of the image density of the printed material.

[0087] The solid content concentration of the coloring agent particle dispersion is preferably 5% by mass or more, more preferably 10% by mass or more, even more preferably 15% by mass or more, and preferably 40% by mass or less, more preferably 30% by mass or less.

[0088] Volume-intermediate particle size D of colorant particles 50 From the viewpoint of improving the dispersibility of the colorant in the toner particles, the particle size is preferably 0.05 μm or more, more preferably 0.08 μm or more, and preferably 0.4 μm or less, more preferably 0.3 μm or less, and even more preferably 0.2 μm or less. The CV value of the colorant particles is preferably 10% or more, more preferably 15% or more, and preferably 40% or less, more preferably 35% or less, and even more preferably 30% or less, from the viewpoint of improving the dispersibility of the colorant in the toner particles. Volume-intermediate particle size D of colorant particles 50 The CV value is measured by the method of the example.

[0089] <<Agglomerants>> In the process of agglomerating resin particles, it is preferable to add a flocculant from the viewpoint of efficiently carrying out the agglomeration. Examples of flocculants include cationic surfactants such as quaternary salts, organic flocculants such as polyethyleneimine, and inorganic flocculants. Examples of inorganic flocculants include inorganic metal salts such as sodium sulfate, sodium nitrate, sodium chloride, calcium chloride, and calcium nitrate; inorganic ammonium salts such as ammonium sulfate, ammonium chloride, and ammonium nitrate; and metal complexes with a valency of 2 or higher. From the viewpoint of improving cohesiveness and obtaining uniform aggregated particles 1, inorganic flocculants with a valency of 1 to 5 are preferred, inorganic metal salts and inorganic ammonium salts with a valency of 1 to 2 are more preferred, inorganic ammonium salts are even more preferred, and ammonium sulfate is even more preferred.

[0090] Using a flocculant, for example, 10 to 50 parts by mass of a flocculant per 100 parts by mass of resin particles is added to a mixed dispersion containing resin particles, release agent particles, and colorant particles at a temperature of 0°C to 40°C, and the resin particles, release agent particles, and colorant particles are flocculated in an aqueous medium to obtain flocculated particles 1. From the viewpoint of promoting flocculation, it is preferable to raise the temperature of the dispersion after adding the flocculant.

[0091] Volume-intermediate particle size D of aggregated particle 1 50 The particle size is preferably 2 μm or more, more preferably 3 μm or more, even more preferably 4 μm or more, and preferably 12 μm or less, more preferably 10 μm or less, and even more preferably 8 μm or less.

[0092] Step 1 preferably includes a step of attaching and agglomerating shell resin particles to the obtained agglomerated particle 1 as a core to obtain agglomerated particle 2. By including a step of agglomerating the shell resin particles, toner particles having a core-shell structure can be obtained. The resin particles for the shell are preferably the resin A described above.

[0093] The resin particle dispersion for the shell is obtained by the same method as the method for producing the resin particle dispersion described above.

[0094] The mass ratio of shell resin particles to the mass of aggregated particles 1 [shell resin particles / aggregated particles 1] is preferably 1 / 99 or more, more preferably 5 / 95 or more, even more preferably 10 / 90 or more, and preferably 25 / 75 or less, more preferably 20 / 80 or less, and even more preferably 15 / 85 or less, from the viewpoint of toner's low-temperature fixation.

[0095] Methods for stopping aggregation include cooling the dispersion, adding an aggregation inhibitor, and diluting the dispersion. From the viewpoint of reliably preventing unnecessary aggregation, adding an aggregation inhibitor to stop aggregation is preferred. Furthermore, if the process involves agglomerating shell resin particles for the purpose of manufacturing toner having a core-shell structure, the aggregation process may be carried out without stopping the aggregation, once the aggregated particles 1 have grown to an appropriate particle size.

[0096] If step 1 includes a step of agglomerating resin particles for the shell, it is preferable to stop the agglomeration in this step when the agglomerated particles 2 have grown to a suitable particle size for toner, and it is preferable to stop the agglomeration by adding an agglomeration inhibitor.

[0097] <<Agglomerating Agent>> As the flocculation inhibitor, surfactants are preferred, and anionic surfactants are more preferred. Examples of anionic surfactants include alkylbenzene sulfonates, alkyl sulfates, polyoxyalkylene alkyl ether sulfates, aryl sulfonates, and aryl sulfonic acid formalin condensates. One or more of these may be used. The flocculation inhibitor may be added in aqueous solution. From the viewpoint of reliably preventing unnecessary aggregation, the amount of aggregation inhibitor added is preferably 2 parts by mass or more, more preferably 5 parts by mass or more, per 100 parts by mass of aggregated particles immediately before adding the aggregation inhibitor, and from the viewpoint of reducing residue in the toner, it is preferably 15 parts by mass or less, more preferably 10 parts by mass or less.

[0098] <Process 2> In step 2, the aggregated particles obtained in step 1 are fused together in an aqueous medium. Fusion bonding fuses the individual particles contained within the aggregated particles, resulting in fused particles. In the fusion process, from the viewpoint of improving the fusion properties of the aggregated particles and improving the productivity of the toner, it is preferable to maintain the aggregated particles at a temperature above the glass transition temperature of the amorphous resin with the highest glass transition temperature among those contained in the aggregated particles. The holding temperature when fusing the aggregated particles is preferably 1°C or higher, more preferably 3°C or higher, than the glass transition temperature of the resin having the highest glass transition temperature among the amorphous resins contained in the aggregated particles, and more preferably 25°C or lower, more preferably 20°C or lower, and even more preferably 15°C or lower, than the glass transition temperature of the resin having the highest glass transition temperature among the amorphous resins. In this case, the time for holding the amorphous resin at a temperature above its glass transition temperature is preferably 1 minute or more, more preferably 10 minutes or more, even more preferably 30 minutes or more, and preferably 240 minutes or less, more preferably 180 minutes or less, even more preferably 120 minutes or less, and even more preferably 90 minutes or less, from the viewpoint of improving toner productivity. Furthermore, it is preferable to maintain the temperature mentioned above until the desired degree of circularity is achieved.

[0099] Volume median particle size D of fused particles obtained by fusion 50 The particle size is preferably 2 μm or more, more preferably 3 μm or more, even more preferably 4 μm or more, and preferably 10 μm or less, more preferably 8 μm or less, and even more preferably 7 μm or less.

[0100] The circularity of the fused particles obtained by fusion is preferably 0.955 or higher, more preferably 0.960 or higher, and more preferably 0.990 or lower, more preferably 0.985 or lower, and even more preferably 0.980 or lower. It is preferable to terminate the fusion process after achieving the desired degree of circularity described above. The roundness is measured by the method described in the examples.

[0101] [Post-processing steps] In the manufacturing method of the present invention, a post-processing step may be performed after step 2, and it is preferable to obtain toner particles by isolation. Since the fused particles obtained in step 2 are present in an aqueous medium, it is preferable to first perform solid-liquid separation. For solid-liquid separation, suction filtration or the like is preferably used. It is preferable to perform washing after solid-liquid separation. At this time, it is also preferable to remove any added surfactants, etc., so if the surfactant has a cloud point, it is preferable to wash with an aqueous medium at or below the cloud point of the surfactant. It is preferable to perform washing multiple times.

[0102] Next, drying is preferable. The drying temperature should preferably be such that the temperature of the fused particles themselves is lower than the glass transition temperature of amorphous resin A, and more preferably 10°C or more lower. Preferred drying methods include vacuum low-temperature drying, vibratory fluid drying, spray drying, freeze-drying, flash jet drying, etc.

[0103] [Toner particles] The volume median diameter D of toner particles 50 is preferably 2 μm or more, more preferably 3 μm or more, still more preferably 4 μm or more, and preferably 10 μm or less, more preferably 8 μm or less, still more preferably 7 μm or less, from the viewpoint of further improving the cleaning property of the toner.

[0104] The CV value of toner particles is preferably 5% or more, more preferably 10% or more, still more preferably 15% or more, and preferably 40% or less, more preferably 35% or less, still more preferably 30% or less, from the viewpoint of improving the productivity of the toner and from the viewpoint of obtaining a high-quality image.

[0105] The roundness of toner particles is preferably 0.955 or more, more preferably 0.960 or more, still more preferably 0.965 or more, and preferably 0.990 or less, more preferably 0.985 or less, still more preferably 0.980 or less. The volume median diameter D of toner particles 50 can be measured by the method described in the examples. The roundness of toner particles can be measured in the same manner as the roundness of fused particles.

[0106] [Toner for electrostatic charge image development] As described above, the toner for electrostatic charge image development obtained by the production method of the present invention contains toner particles. Although the toner particles can be used as they are as the toner, it is preferable to use those obtained by adding a fluidizing agent or the like as an external additive to the surface of the toner particles.

[0107] [External additive] Examples of the external additive include fine particles of inorganic materials such as hydrophobic silica, titanium oxide, alumina, cerium oxide, and carbon black, and polymer fine particles such as polycarbonate, polymethyl methacrylate, and silicone resin. Among these, hydrophobic silica is preferable. The external additive may be used alone or in combination of two or more. Also, two or more types of hydrophobic silica having different particle sizes may be used. When surface treatment of toner particles is performed using an external additive, the amount of external additive added is preferably 1 part by mass or more, more preferably 2 parts by mass or more, even more preferably 3 parts by mass or more, and preferably 5 parts by mass or less, more preferably 4.5 parts by mass or less, and even more preferably 4 parts by mass or less, per 100 parts by mass of toner particles.

[0108] Toner is used in electrophotographic printing for electrostatic image development. Toner can be used, for example, as a one-component developer, or mixed with a carrier to form a two-component developer. [Examples]

[0109] The present invention will be specifically described below with reference to examples, but the present invention is not limited in any way by these examples. Each property value was measured and evaluated by the following method. In notations such as "alkylene oxide (X)," the number X in parentheses represents the average number of moles of alkylene oxide added.

[0110] [Measurement method] The properties of internal olefins, internal olefin sulfonates, polyester resins, resin particles, toners, etc., were measured and evaluated using the following methods. [Position of double bond in internal olefin] The double bond positions of the internal olefin were determined by gas chromatography (GC). Specifically, the internal olefin was reacted with dimethyl disulfide to form a dithiolated derivative, and then each component was separated by GC. The double bond positions of the internal olefin were determined from the peak areas of each component. The equipment and analytical conditions used for the measurement are as follows: • GC device: "HP6890" (manufactured by Hewlettpackard) • Column: "Ultra-Alloy-1HT Capillary Column (30m x 250μm x 0.15μm)" (Manufactured by Frontier Lab Co., Ltd.) • Detector: Flame Ion Detector (FID) Injection temperature: 300℃ Detector temperature: 350℃ ·He flow rate: 4.6mL / min

[0111] [Mass ratio of hydroxyl compound / olefin compound] The mass ratio of the hydroxyl derivative to the olefin derivative was measured by HPLC-MS. Specifically, the hydroxyl derivative and the olefin derivative were separated by HPLC and identified by MS. The proportion of each was determined from the GC-MS peak area. The equipment and conditions used for the measurement are as follows: • HPLC system: Agilent Technologies 1100 (manufactured by Agilent Technologies) • Column: "L-columnODS4.6×150mm" (manufactured by the Chemicals Evaluation and Research Institute) Sample preparation: Dilute 1000-fold with methanol. • Eluent A: Water with 10mM ammonium acetate added • Eluent B: Methanol with 10mM ammonium acetate added • Gradient: (0 min (A / B = 30 / 70 (volume ratio, same applies below)) → 10 min (30 / 70) → 55 min (0 / 100) → 65 min (0 / 100) → 66 min (30 / 70) → 75 min (30 / 70)) MS unit: Agilent Technologies 1100MS SL (G1946D) (manufactured by Agilent Technologies) MS detection: Anion detection (m / z 60~1600, UV 240nm)

[0112] [Olefin content within the raw material] The content of internal olefins in the raw materials was measured by GC. Specifically, ethanol and petroleum ether were added to an aqueous solution of internal olefin sulfonate, and then the mixture was extracted to obtain olefins in the petroleum ether phase. The amount of olefins was quantified from the GC peak area. The equipment and analytical conditions used for the measurement are as follows: • GC unit: "Agilent Technologies 6850" (manufactured by Agilent Technologies) • Column: "Ultra-Alloy-1HT Capillary Column 15m x 250μm x 0.15μm" (Manufactured by Frontier Labs Co., Ltd.) • Detector: Flame Ion Detector (FID) Injection temperature: 300℃ Detector temperature: 350℃ ·He flow rate: 3.8mL / min

[0113] [Content of inorganic compounds] The inorganic compound content was measured by potentiometric titration and neutralization titration. Specifically, the Na2SO4 content was measured by sulfate (SO4 2- The concentration was determined by potentiometric titration. The NaOH content was determined by neutralization titration with dilute hydrochloric acid.

[0114] [Softening point, crystallinity index, melting point, and glass transition temperature of resins] (1) Softening point Using a flow tester "CFT-500D" (manufactured by Shimadzu Corporation), 1 g of sample was heated at a heating rate of 6°C / min while a load of 1.96 MPa was applied by a plunger, and the sample was extruded from a nozzle with a diameter of 1 mm and a length of 1 mm. The amount of plunger descent of the flow tester was plotted against temperature, and the temperature at which half of the sample flowed out was defined as the softening point. (2) Crystallinity index Using a differential scanning calorimeter "Q100" (manufactured by T.A. Instruments Japan Co., Ltd.), 0.02 g of the sample was weighed into an aluminum pan and cooled to 0°C at a cooling rate of 10°C / min. The sample was then left to stand still for 1 minute, and then heated to 180°C at a heating rate of 10°C / min, and the amount of heat was measured. Among the observed endothermic peaks, the temperature of the peak with the largest peak area was defined as the maximum endothermic peak temperature (1), and the crystallinity index was determined by (softening point (°C)) / (maximum endothermic peak temperature (1) (°C)). (3) Melting point and glass transition temperature Using a differential scanning calorimeter "Q100" (manufactured by T.A. Instruments Japan Co., Ltd.), 0.02 g of the sample was weighed into an aluminum pan, heated to 200°C, and then cooled to 0°C at a rate of 10°C / min. The sample was then heated again at a rate of 10°C / min, and the amount of heat was measured. Among the observed endothermic peaks, the temperature of the peak with the largest peak area was defined as the maximum endothermic peak temperature (2). In the case of crystalline resins, this peak temperature was defined as the melting point. Furthermore, in the case of amorphous resins, if a peak was observed, the temperature of that peak was defined as the glass transition temperature. If no peak was observed but a step was observed, the temperature at the intersection of the tangent line showing the maximum slope of the curve in the step portion and the extension of the baseline on the low-temperature side of the step was defined as the glass transition temperature.

[0115] [Acid value of resins] The acid value of the resin was measured according to the neutralization titration method described in JIS K 0070:1992. However, the measurement solvent was a mixed solvent of acetone and toluene (acetone:toluene = 1:1 (volume ratio)).

[0116] [Melting point of release agent] Using a differential scanning calorimeter "Q100" (manufactured by T.A. Instruments Japan Co., Ltd.), 0.02 g of the sample was weighed into an aluminum pan, heated to 200°C, and then cooled from 200°C to 0°C at a rate of 10°C / min. Next, the sample was heated again at a rate of 10°C / min, the amount of heat was measured, and the maximum peak temperature of endothermic reaction was defined as the melting point.

[0117] [Volume median particle size D of resin particles, colorant particles, and mold release agent particles] 50 [and CV value] (1) Measuring device: Laser diffraction particle size analyzer "LA-920" (manufactured by Horiba, Ltd.) (2) Measurement conditions: Take the sample dispersion into a measuring cell, add distilled water, and adjust the concentration to the appropriate range for absorbance, using a volume-average particle size D. 50 The volume-average particle size Dv was also measured. Furthermore, the CV value was calculated according to the following formula. CV value (%) = (Standard deviation of particle size distribution / Volume-average particle size Dv) × 100

[0118] [Solid content concentration of resin particle dispersion, colorant particle dispersion, and mold release agent particle dispersion] The moisture content (mass%) of a 5g sample was measured using an infrared moisture meter "FD-230" (manufactured by Kett Scientific Research Institute Co., Ltd.) at a drying temperature of 150°C and measurement mode 96 (monitoring time 2.5 minutes, moisture content fluctuation range 0.05%). The solid content concentration was calculated according to the following formula. Solid concentration (mass%) = 100-moisture (mass%)

[0119] [Volume-intermediate particle size D of aggregated particles] 50 ] • Measuring instrument: "Coulter Multisizer (registered trademark) III" (manufactured by Beckman Coulter, Inc.) • Aperture diameter: 50 μm • Analysis software: "Multisizer (registered trademark) III version 3.51" (manufactured by Beckman Coulter, Inc.) • Electrolyte: "Isoton (registered trademark) II" (manufactured by Beckman Coulter, Inc.) • Measurement conditions: The sample dispersion was added to 100 mL of the electrolyte solution to adjust the concentration to a level that would allow for the measurement of 30,000 particle sizes in 20 seconds. Then, 30,000 particles were measured again, and the volume median particle size D was determined from the particle size distribution. 50 They sought it.

[0120] [Circularity of fused particles] • Measurement device: Flow-type particle image analyzer "FPIA-3000" (manufactured by Sysmex Corporation) • Preparation of dispersion: The dispersion of fused particles was prepared by diluting it with deionized water to a solid content concentration of 0.001 to 0.05% by mass. • Measurement mode: The circularity of the fused particles was measured using HPF measurement mode.

[0121] [Toner particle volume medium particle size D] 50 [and CV value] The measuring device, aperture diameter, analysis software, and electrolyte are the volume median particle size D of the aggregated particles as described above. 50 The same equipment used in the measurement was employed. • Dispersion: Polyoxyethylene lauryl ether "Emulgen® 109P" (manufactured by Kao Corporation, HLB (Hydrophile-Lipophile Balance) = 13.6) was dissolved in the electrolyte to obtain a dispersion with a concentration of 5% by mass. • Dispersion conditions: 10 mg of the measurement sample of dried toner particles was added to 5 mL of the dispersion, dispersed for 1 minute using an ultrasonic disperser, then 25 mL of the electrolyte was added, and dispersed for another minute using an ultrasonic disperser to prepare the sample dispersion. • Measurement conditions: The sample dispersion is added to 100 mL of the electrolyte to adjust the concentration to a level that allows for the measurement of 30,000 particle sizes in 20 seconds. Then, 30,000 particles are measured, and the volume median particle size D is determined from the particle size distribution. 50 and volume-average particle size D V They sought it. Furthermore, the CV value (%) was calculated according to the following formula. CV value (%) = (Standard deviation of particle size distribution / Volume average particle size D) V ) × 100

[0122] [Manufacturing of internal olefin sulfonates] Manufacturing example G1 (Synthesis of internal olefin sulfonate G-1 (18 carbon atoms)) 7,000 g (25.9 mol) of 1-octadecanol "Calcol 8098" (manufactured by Kao Corporation) and 700 g (10% by mass relative to the starting alcohol) of γ-alumina (STREM Chemicals, Inc.) as a solid acid catalyst were charged into a flask equipped with a stirring device. The reaction was carried out for 5 hours at 280°C with stirring while circulating nitrogen (7,000 mL / min) through the system. After the reaction, the alcohol conversion rate was 100% by mass, and the purity of the C18 internal olefin was 99.7% by mass. The obtained crude internal olefin was transferred to a distillation flask and distilled at 136-160°C / 4.0 mmHg to obtain a C18 internal olefin with an olefin purity of 100% by mass. The double bond distribution of the obtained internal olefin was as follows: C1 position 2.3 mass%, C2 position 26.3 mass%, C3 position 20.8 mass%, C4 position 17.2 mass%, C5 position 11.7 mass%, C6 position 8.3 mass%, C7 position 5.9 mass%, and the sum of C8 and C9 positions was 7.2 mass%.

[0123] The internal olefin of C18 was placed in a thin-film sulfonation reactor with an external jacket, and the sulfonation reaction was carried out using sulfur trioxide gas under conditions of passing 20°C cooling water through the reactor's external jacket. The molar ratio of SO3 / internal olefin during the sulfonation reaction was set to 1.09. The resulting sulfonate was added to an alkaline aqueous solution prepared with 1.5 molar times the theoretical acid value of sodium hydroxide, and neutralized at 30°C for 1 hour with stirring. The neutralized product was hydrolyzed by heating in an autoclave at 160°C for 1 hour to obtain the crude product of sodium C18 internal olefin sulfonate. 300 g of the crude product was transferred to a separatory funnel, 300 mL of ethanol was added, and then 300 mL of petroleum ether was added in each step to extract and remove oil-soluble impurities. At this time, inorganic compounds (main component being Glauber's salt) precipitated at the oil-water interface due to the addition of ethanol were also separated and removed from the aqueous phase by oil-water separation. This extraction and removal operation was performed three times. By evaporating the aqueous phase to dryness, we obtained C18 internal olefin sulfonate sodium (internal olefin sulfonate G-1). The mass ratio of the hydroxy compound (sodium hydroxyalkanesulfonate) to the olefin compound (sodium olefinsulfonate) in the obtained sodium internal olefin sulfonate was 84 / 16. Furthermore, the content of the raw material internal olefin in the obtained sodium internal olefin sulfonate was less than 100 ppm (less than the GC detection limit (100 ppm)), and the inorganic compounds were below the detection limits of potentiometric titration and neutralization titration.

[0124] Manufacturing example G2 (Synthesis of internal olefin sulfonate G-2 (16 carbon atoms)) Except for using 7,000 g (28.9 mol) of 1-hexadecanol "Calcol 6098" (manufactured by Kao Corporation) instead of 1-octadecanol, the same procedure as in Production Example G1 was used to obtain an internal olefin with 16 carbon atoms and a purity of 100% by mass. The double bond distribution of the obtained internal olefin was as follows: C1 position 2.3 mass%, C2 position 23.6 mass%, C3 position 18.9 mass%, C4 position 17.5 mass%, C5 position 13.7 mass%, C6 position 11.2 mass%, and the sum of C7 and C8 positions was 12.8 mass%.

[0125] C16 internal olefin sulfonate sodium (internal olefin sulfonate G-2) was obtained in the same manner as in production example G1, except that C16 internal olefin was used instead of C18 internal olefin. The mass ratio of the hydroxy compound (sodium hydroxyalkanesulfonate) to the olefin compound (sodium olefinsulfonate) in the obtained internal olefin sulfonate sodium was 88 / 12. Furthermore, the content of the raw material internal olefin in the obtained internal olefin sulfonate sodium was less than 100 ppm (less than the GC detection limit (100 ppm)), and the inorganic compounds were below the detection limits of potentiometric titration and neutralization titration.

[0126] Manufacturing example G3 (Synthesis of internal olefin sulfonate G-3 (20 carbon atoms)) An internal olefin with 20 carbon atoms and an olefin purity of 100% by mass was obtained in the same manner as in Production Example G1, except that 7,000 g (23.4 mol) of 1-eicosanol (product name: 1-Eicosanol, manufactured by Tokyo Chemical Industry Co., Ltd.) was used instead of 1-octadecanol. The double bond distribution of the obtained internal olefin was as follows: C1 position 2.5 mass%, C2 position 25.2 mass%, C3 position 20.5 mass%, C4 position 16.1 mass%, C5 position 11.1 mass%, C6 position 8.8 mass%, C7 position 6.9 mass%, C8 position 4.3 mass%, and the sum of C9 and C10 positions was 4.6 mass%.

[0127] C20 internal olefin sulfonate sodium (internal olefin sulfonate G-3) was obtained in the same manner as in production example G1, except that C20 internal olefin was used instead of C18 internal olefin. The mass ratio of the hydroxy compound (sodium hydroxyalkanesulfonate) to the olefin compound (sodium olefinsulfonate) in the obtained sodium internal olefin sulfonate was 84 / 16. Furthermore, the content of the raw material internal olefin in the obtained sodium internal olefin sulfonate was less than 100 ppm (less than the GC detection limit (100 ppm)), and the inorganic compounds were below the detection limits of potentiometric titration and neutralization titration.

[0128] [Resin manufacturing] Manufacturing Example A1 (Manufacturing of Amorphous Polyester Resin A-1) As shown in Table 1, the raw material monomers for polyester resins other than trimellitic anhydride, the esterification catalyst, and the esterification co-catalyst were placed in a 10-liter four-necked flask equipped with a nitrogen inlet tube, a dehydration tube, a stirrer, and a thermocouple. The mixture was heated to 235°C under a nitrogen atmosphere, and then polycondensed at 235°C for 6 hours. After that, the temperature was lowered to 210°C, trimellitic anhydride was added, and the mixture was reacted at 210°C for 1 hour. The reaction was then carried out at 210°C under reduced pressure of 10 kPa until the softening point shown in Table 1 was reached to obtain amorphous polyester resin A-1. The physical properties are shown in Table 1.

[0129] Manufacturing Example B1 (Manufacturing of Amorphous Polyester Resin B-1) The polyester resin raw material monomers other than fumaric acid and trimellitic anhydride shown in Table 1, along with the esterification catalyst and esterification co-catalyst, were placed in a 10 L four-necked flask equipped with a nitrogen inlet tube, dehydration tube, stirrer, and thermocouple. The mixture was heated in a mantle heater under a nitrogen atmosphere from 180°C to 230°C over 6 hours, and the reaction was carried out at 230°C for 3 hours. After cooling to 180°C, fumaric acid, trimellitic anhydride, and a radical polymerization inhibitor were added, the temperature was raised to 220°C, and then the pressure in the flask was reduced to 10 kPa. The reaction was carried out under reduced pressure to the softening point shown in Table 1 to obtain amorphous polyester resin B-1. The physical properties are shown in Table 1. Although amorphous polyester resin B-1 is resin A, it is designated as "B-1" for convenience because it is used for shell formation.

[0130] [Table 1]

[0131] Manufacturing Example C1 (Manufacturing of Crystalline Polyester Resin C-1) As shown in Table 2, the raw material monomers for the polyester resin were placed in a 10-liter four-necked flask equipped with a nitrogen inlet tube, dehydration tube, stirrer, and thermocouple. The flask was purged with nitrogen, stirred, and heated to 135°C. After holding at 135°C for 3 hours, the temperature was raised from 135°C to 200°C over 10 hours. Subsequently, an esterification catalyst was added, and the flask was held at 200°C for another hour. The pressure inside the flask was then reduced to 8 kPa, and the reaction was carried out under reduced pressure until the softening point shown in Table 2 was obtained, yielding crystalline polyester resin C-1. The physical properties are shown in Table 2.

[0132] Manufacturing Example C2 (Manufacturing of Crystalline Polyester Resin C-2) As shown in Table 2, crystalline polyester resin C-2 was obtained in the same manner as in Production Example C1, except that the raw material monomers and esterification catalyst for the polyester resin were used. The physical properties are shown in Table 2.

[0133] [Table 2]

[0134] [Manufacturing of resin particle dispersions] Manufacturing Example X1 (Manufacturing of Resin Particle Dispersion X-1) In a 3L container equipped with a stirrer, reflux condenser, dropping funnel, thermometer, and nitrogen inlet tube, 180g of resin A-1, 20g of resin C-1, and 200g of methyl ethyl ketone were placed, and the resins were dissolved at 73°C for 2 hours. To the resulting solution, a 5% by mass aqueous sodium hydroxide solution was added to achieve a degree of neutralization of 60 mol% relative to the acid value of the resin, and the mixture was stirred for 30 minutes. Next, while maintaining the temperature at 73°C, 700 g of deionized water was added over 50 minutes while stirring at 280 r / min to induce phase inversion emulsification. While continuing to maintain the temperature at 73°C, methyl ethyl ketone was removed under reduced pressure to obtain an aqueous dispersion of resin particles. Subsequently, the aqueous dispersion was cooled to 30°C while continuing to stir, and then deionized water was added to achieve a solid content concentration of 20% by mass to obtain resin particle dispersion X-1. The median particle size of the resin particles was D. 50 The CV values ​​are shown in Table 3.

[0135] Manufacturing Examples X2, X'3 (Manufacturing of resin particle dispersions X-2 and X'-3) Resin particle dispersions X-2 and X'-3 were obtained in the same manner as in production example X1, except that the type and amount of resin used were changed as shown in Table 3. The volume-median particle size D of the resin particles 50 The corresponding CV values ​​are shown in Table 3.

[0136] [Table 3]

[0137] Manufacturing Example Y1 (Manufacturing of resin particle dispersion Y-1) In a 3L container equipped with a stirrer, reflux condenser, dropping funnel, thermometer, and nitrogen inlet tube, 200g of resin B-1 and 200g of methyl ethyl ketone were placed, and the resin was dissolved at 73°C for 2 hours. To the resulting solution, a 5% by mass aqueous sodium hydroxide solution was added to achieve a degree of neutralization of 60 mol% relative to the acid value of the resin, and the mixture was stirred for 30 minutes. Next, while maintaining the temperature at 73°C, 700 g of deionized water was added over 50 minutes while stirring at 280 r / min to induce phase inversion emulsification. While continuing to maintain the temperature at 73°C, methyl ethyl ketone was removed under reduced pressure to obtain an aqueous dispersion of resin particles. Subsequently, the aqueous dispersion was cooled to 30°C while continuing to stir, and then deionized water was added to achieve a solid content concentration of 20% by mass to obtain resin particle dispersion Y-1. The median particle size of the resin particles was D. 50 The particle size was 0.10 μm, and the CV value was 26%.

[0138] Manufacturing example D1 (Manufacturing of composite resin D-1) A 10L four-necked flask equipped with a nitrogen inlet tube, dehydration tube, stirrer, and thermocouple was purged with nitrogen. 4313g of bisphenol A propylene oxide (2,2) adduct, 818g of terephthalic acid, 30g of tin(II) di(2-ethylhexanoate), and 3.0g of gallic acid were added. Under a nitrogen atmosphere, the reaction system was stirred and heated to 235°C, where it was maintained for 5 hours. After that, the pressure inside the flask was reduced and maintained at 8kPa for 1 hour. After returning to atmospheric pressure, it was cooled to 160°C and maintained at 160°C. A mixture of 2756g of styrene, 689g of stearyl methacrylate, 142g of acrylic acid, and 413g of dibutyl peroxide was added dropwise to the reaction system over 3 hours. The reaction system was then maintained at 160°C for 30 minutes, then the temperature was raised to 200°C, the pressure in the flask was further reduced to 8 kPa, and it was maintained under reduced pressure for 1 hour. After returning to atmospheric pressure, it was cooled to 190°C, 727 g of succinic acid was added, the temperature was raised to 210°C at a rate of 10°C / hr, and then the reaction was carried out at 4 kPa until the softening point shown in Table 4 was reached to obtain composite resin D-1. The physical properties are shown in Table 4.

[0139] [Table 4]

[0140] Manufacturing Example S1 (Manufacturing of Resin Particle Dispersion S-1) In a 3L container equipped with a stirrer, reflux condenser, dropping funnel, thermometer, and nitrogen inlet tube, 200g of resin D-1 and 200g of methyl ethyl ketone were placed, and the resin was dissolved at 73°C for 2 hours. To the resulting solution, a 5% by mass aqueous sodium hydroxide solution was added to achieve a degree of neutralization of 60 mol% relative to the acid value of resin D-1, and the mixture was stirred for 30 minutes. Next, while maintaining the temperature at 73°C, 700 g of deionized water was added over 50 minutes while stirring at 280 r / min to induce phase inversion emulsification. While continuing to maintain the temperature at 73°C, methyl ethyl ketone was removed under reduced pressure to obtain an aqueous dispersion of resin particles. Subsequently, the aqueous dispersion was cooled to 30°C while stirring at 280 r / min, and then deionized water was added to achieve a solid content concentration of 20% by mass to obtain resin particle dispersion S-1. The medium volume particle size D of the resin particles... 50 The particle size was 0.09 μm, and the CV value was 23%.

[0141] [Manufacturing of mold release agent particle dispersion] Manufacturing Example W1 (Manufacturing of Release Agent Particle Dispersion W-1) In a 1L beaker, 120g of deionized water, 86g of resin particle dispersion S-1, and 40g of paraffin wax "HNP-9" (manufactured by Nippon Seiro Co., Ltd., melting point 75℃) were added, and the mixture was stirred while maintaining a temperature of 90-95℃ to melt it, obtaining a molten mixture. The obtained molten mixture was subjected to dispersion treatment for 20 minutes using an ultrasonic homogenizer "US-600T" (manufactured by Nippon Seiki Seisakusho Co., Ltd.) while maintaining the temperature at 90-95°C, and then cooled to room temperature (20°C). Deionized water was added to the obtained dispersion to adjust the solid content concentration to 20% by mass, and release agent particle dispersion W-1 was obtained. The volume-median particle size D of the release agent particles 50 The particle size was 0.47 μm, and the CV value was 27%.

[0142] [Manufacturing of colorant particle dispersion] Manufacturing Example Z1 (Manufacturing of Colorant Particle Dispersion Z-1) In a 1L beaker, 116.2g of copper phthalocyanine pigment "ECB-301" (manufactured by Dainichi Seika Kogyo Co., Ltd.), 154.9g of anionic surfactant "Neoperex® G-15" (manufactured by Kao Corporation, 16% by mass sodium dodecylbenzenesulfonate aqueous solution), and 340g of deionized water were mixed and dispersed at room temperature for 3 hours using an ultrasonic homogenizer "US-600T" (manufactured by Nippon Seiki Seisakusho Co., Ltd.). Then, deionized water was added to obtain a colorant particle dispersion Z-1 by reducing the solid content concentration to 20% by mass. Medium volume particle size D of the colorant particles50 The particle size was 0.12 μm, and the CV value was 22%.

[0143] Example 1 (Manufacturing of Toner 1) In a 3L four-necked flask equipped with a dehydration tube, a stirrer, and a thermocouple, 500g of resin particle dispersion X-1, 25g of mold release agent particle dispersion W-1, 25g of coloring agent particle dispersion Z-1, and an aqueous solution of 3g of internal olefin sulfonate G-1 dissolved in 12g of deionized water were added and mixed at a temperature of 25°C. Next, while stirring the mixture, an aqueous solution of 43g of ammonium sulfate dissolved in 980g of deionized water, to which a 4.8% by mass potassium hydroxide aqueous solution was added to adjust the pH to 8.2 was added dropwise over 10 minutes at 25°C, and the temperature was raised to 55°C over 2 hours to determine the volume-median particle size D of the aggregated particles. 50 The mixture was kept at 55°C until it reached a size of 6.8 μm, and a dispersion of aggregated particles 1 was obtained. The dispersion of aggregated particles 1 was cooled to 50°C, and while maintaining the temperature at 50°C, 75 g of resin particle dispersion Y-1 was added over 90 minutes to obtain a dispersion of aggregated particles 2, in which resin particles aggregated onto aggregated particles 1. To the resulting dispersion of aggregated particles 2, 22 g of polyoxyethylene lauryl ether sodium sulfate "Emal E-27C" (manufactured by Kao Corporation, anionic surfactant, effective concentration 27% by mass) and 1100 g of deionized water were added. The mixture was then heated to 75°C over 1 hour and maintained at 75°C until the circularity reached 0.970, thereby obtaining a dispersion of fused particles in which the aggregated particles 2 had fused together. The resulting dispersion of fused particles was cooled to 30°C, and the dispersion was filtered by suction to separate the solid components. The mixture was then washed with deionized water at 25°C and filtered by suction at 25°C for 2 hours. Subsequently, toner particles 1 were obtained by vacuum drying at 33°C for 24 hours using a vacuum constant-temperature dryer "DRV622DA" (manufactured by ADVANTEC). The physical properties of toner particles 1 are shown in Table 5. 100 parts by mass of toner particles 1, 2.5 parts by mass of hydrophobic silica "RY50" (manufactured by Nippon Aerosil Co., Ltd., average particle size: 0.04 μm), and 1.0 part by mass of hydrophobic silica "Cabosil® TS720" (manufactured by Cabot Japan Co., Ltd., average particle size: 0.012 μm) were placed in a Henschel mixer and stirred. The mixture was then passed through a 150-mesh sieve to obtain toner 1, which was then evaluated as follows. The results are shown in Table 5.

[0144] [evaluation] [Low temperature retention] Using high-quality paper "J Paper A4 size" (manufactured by Fujifilm Business Innovation Co., Ltd.) and a commercially available printer "Microline® 5400" (manufactured by Oki Electric Industry Co., Ltd.), the amount of toner adhering to the paper was 0.60 ± 0.01 mg / cm². 2 The resulting solid image was printed on A4 paper, leaving a 5mm margin at the top edge, and extending to a length of 50mm without being fixed. Next, a printer of the same model with a modified fuser unit that allows for variable temperature control was prepared. The fuser unit temperature was set to 90°C, and toner was fixed at a speed of 1.2 seconds per sheet in the A4 portrait direction to obtain a printed document. Using a similar method, the fuser temperature was increased by 5°C increments to fix the toner and obtain printed materials. From the top margin of the printed image to the solid image, lightly attach a 50mm length of Scotch® Mending Tape 810 (manufactured by 3M Japan Ltd., 18mm wide), then place a 500g weight (contact area 1,963mm²) on top. 2 A sample was placed on top and pressed back and forth once at a speed of 10 mm / s. Then, the attached tape was peeled off from the bottom end at a peeling angle of 180° and a speed of 10 mm / s to obtain the printed material after tape removal. Thirty sheets of high-quality paper "Excellent White Paper A4 size" (manufactured by OKI Electric Industry Co., Ltd.) were placed under the printed material before and after tape application, and the reflected image density of the fixed image portion of each printed material before and after tape application was measured using a colorimeter "SpectroEye" (manufactured by X-Rite, lighting conditions: standard light source D50, observation field of view 2°, density standard DINNB, absolute white standard), and the fixing rate was calculated from each reflected image density according to the following formula. Fixation rate (%) = (Reflective image density after tape removal / Reflective image density before tape application) × 100 The lowest temperature at which a fixation rate of 90% or higher was defined as the minimum fixation temperature. A lower minimum fixation temperature indicates superior low-temperature fixation performance.

[0145] [Dot Reproducibility] A 2-dot, 2-space halftone image was printed on high-quality paper "J Paper A4 size" (manufactured by Fujifilm Business Innovation Co., Ltd.) using a commercially available printer "Microline® 5400" (manufactured by Oki Electric Industry Co., Ltd.) at a resolution of 1200 dpi. This was visually evaluated on the following five-point scale. A higher number indicates less toner scattering around the dots and less white space within the dots, resulting in clearer dots. 5: Almost no toner splatter was observed around the dots, the dots were very clear, and there were no white gaps within the dots. 4: Although a small amount of scattered toner is visible around the dot, the dot is clear and there are no white gaps within the dot. 3: Although some toner splatter is visible around the dots, making them slightly indistinct, no white areas are observed within the dots. 2: Toner splatter is visible around the dots, making the dots somewhat indistinct, and white areas within the dots can also be observed. 1: Toner splatter is noticeable around the dots, making the dots unclear, and white areas within the dots are also noticeable.

[0146] Examples 2-6, Comparative Examples 1-3 (Manufacturing of toners 2-6 and c1-c3) Except for changing the type of resin particle dispersion, the type and amount of surfactant used, as shown in Table 5, toner particles 2-6, c1-c3, and toners 2-6, c1-c3 were manufactured in the same manner as in Example 1. The physical properties of toner particles 2-6, c1-c3, and the evaluation results of toners 2-6, c1-c3 are shown in Table 5.

[0147] [Table 5]

[0148] Table 5 shows that the toner obtained by the toner manufacturing method of the present invention exhibits excellent low-temperature fixing properties and dot reproducibility (Examples 1-6). In contrast, the toner produced using sodium 1-octadecanesulfonate instead of the internal olefin sulfonate exhibits poor low-temperature fixing properties and dot reproducibility (Comparative Example 1). Furthermore, the toner produced using sodium dodecyl sulfate instead of the internal olefin sulfonate and the toner produced without using resin C also exhibit poor low-temperature fixing properties (Comparative Examples 2 and 3).

Claims

1. A method for manufacturing toner for electrostatic image development, comprising the following steps 1 and 2 in this order. Step 1: A process to obtain aggregated particles by agglomerating resin particles containing amorphous polyester resin A and crystalline polyester resin C in the same or different particles in an aqueous medium containing an internal olefin sulfonate with 14 to 22 carbon atoms. Step 2: A step to obtain fused particles by fusing the obtained aggregated particles.

2. A method for producing electrostatic image developing toner according to claim 1, wherein the content of the hydroxyl derivative in the internal olefin sulfonate having 14 to 22 carbon atoms is 50% by mass or more.

3. A method for producing electrostatic image developing toner according to claim 1 or 2, wherein the mass ratio of the hydroxyl compound to the olefin compound (hydroxyl compound / olefin compound) in the internal olefin sulfonate having 14 to 22 carbon atoms is 50 / 50 or more.

4. A method for producing a toner for electrostatic image developing according to claim 1 or 2, wherein the amount of internal olefin sulfonate having 14 to 22 carbon atoms added to the aqueous medium in step 1 is 0.1 parts by mass to 15 parts by mass per 100 parts by mass of resin particles.

5. A method for producing electrostatic image developing toner according to claim 1 or 2, wherein the concentration of an internal olefin sulfonate having 14 to 22 carbon atoms in the aqueous medium of step 1 is 0.5 g / L or more and 15.0 g / L or less.

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