Resin particle and method for producing the same

Abstract

To provide resin particles which are excellent in fixability and charging property.SOLUTION: Resin particles contain Mg and Na as metal elements, wherein a Mg content (mass%) in the resin particles measured by fluorescent X-ray analysis is smaller than an Na content (mass%) in the resin particles measured by the fluorescent X-ray analysis.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to resin particles and a method for producing the same. [Background technology]

[0002] Resin particles are widely used as toners for image forming devices such as multifunction peripherals (MFPs) and printers in various places, including offices. To reduce the environmental impact of toners, various approaches have been considered, including reducing power consumption by improving the low-temperature fixability of the toner itself, reducing energy consumption during production, using biomass (plant-derived) resins as binder resins, and using recycled materials as binder resins. In particular, given the increasing importance of resource conservation, energy conservation, and resource recycling, there is a growing demand for using recycled materials such as polyethylene terephthalate or polybutylene terephthalate as binder resins.

[0003] Patent Document 1 (JP 2022-181043 A) describes a binder resin having an acid value of 5 mgKOH / g or more and 25 mgKOH / g or less, and a pigment having an isoindoline skeleton, and the net strength N of the total of alkali metals and alkaline earth metals measured by fluorescent X-ray analysis. A The present invention discloses a toner for developing electrostatic images having toner particles with a viscosity of 1.50 kcps or more and 4.00 kcps or less. Patent Document 2 (Japanese Patent No. 4625386) describes a toner for developing electrostatic images, which has a structure with a core portion containing at least a colorant, a release agent, and a binder resin (A), and a shell portion made of a binder resin (B) that covers the core portion, and the shell portion made of the binder resin (B) is formed by aggregating fine particles made of a vinyl copolymer resin into the core portion using an aggregating agent, and the toner is characterized in that (1) the aggregating agent contains Mg2+, and the peak intensity of the Mg specific X-ray Kα measured with a fluorescent X-ray analyzer is in the range of 3 to 30 Kcps, or (2) the aggregating agent contains Ca 2+ (3) the aggregating agent contains Al, and the peak intensity of the Ca-specific X-ray Kα measured by a fluorescent X-ray analyzer for the toner is in the range of 45 to 500 Kcps;3+ The toner has a peak intensity of Al specific X-ray Kα of 3 to 30 Kcps when measured with a fluorescent X-ray analyzer, the binder resin (A) contains at least a resin having a polyester skeleton, the binder resin (B) is a vinyl copolymer resin, the weight ratio of the shell portion to the core portion is 0.05 to 0.5, and the volume average particle size of the toner is 3 to 8 μm. Patent Document 3 (Japanese Patent Publication No. 7069809) discloses toner particles in which the proportion of polyester resin in the binder resin is 60% by mass or more, the toner particles contain polyester resin having an acid value of 10 mgKOH / g or more and less than 15 mgKOH / g, the acid value of the surface of the toner particles is in the range of 0.3% or more and 1.7% or less of the acid value of the polyester resin, the melt viscosity of the toner particles at 100°C is 1800 Pa·s or more and 3800 Pa·s or less, and the glass transition temperature (Tg) of the toner particles is 30°C or more and 55°C or less, and the amounts of Na, S and Al in the toner particles are set within specific ranges. Patent Document 4 (JP 2010-145508 A) discloses a toner containing a binder resin and a colorant, having a glass transition temperature (Tg) of 50°C or higher, a sodium ion amount of 100 ppm or less in a dispersion liquid obtained by dispersing the toner in an aqueous medium at a temperature of the glass transition temperature (Tg) + 10°C, and a sodium ion amount of 800 ppm or more and 20,000 ppm or less in a dispersion liquid obtained by dispersing the toner in an aqueous medium at a temperature of the glass transition temperature (Tg) + 10°C. Summary of the Invention [Problem to be solved by the invention]

[0004] An object of the present invention is to provide resin particles that are excellent in fixability and chargeability. [Means for solving the problem]

[0005] The above problem is solved by the following configuration 1). 1) Resin particles containing Mg and Na as metal elements, Resin particles, characterized in that the Mg content (mass%) in the resin particles measured by fluorescent X-ray analysis is less than the Na content (mass%) in the resin particles measured by fluorescent X-ray analysis. [Effects of the Invention]

[0006] According to the present invention, it is possible to provide resin particles that are excellent in fixability and chargeability. DETAILED DESCRIPTION OF THE INVENTION

[0007] An embodiment of the present invention will be described. (1) The resin particles of the present invention are characterized in that they contain Mg and Na as metal elements, and the Mg content (mass%) in the resin particles measured by X-ray fluorescence analysis is less than the Na content (mass%) in the resin particles measured by X-ray fluorescence analysis. The above-mentioned requirement of the present invention can be met, for example, when resin particles are produced by a production method including a step of preparing a solution by dissolving or dispersing a resin in an organic solvent, a step of adding water to the solution to invert the phase from a water-in-oil dispersion to an oil-in-water dispersion, and an aggregation step of aggregating fine particles in the oil-in-water dispersion using an aggregating agent and terminating the aggregation at a predetermined point using a terminator, by weakening the stirring during the aggregation step. Examples of ways to weaken the stirring include using anchor blades that have less vertical convection as stirring blades or not providing baffles in the stirring tank. By weakening the agitation, the amount of aggregating agent (Mg) required to form resin particles can be reduced, and the liquid temperature can be lowered. Furthermore, because the amount of Mg used is small, chargeability, environmental anisotropy, and transferability can be improved. On the other hand, by weakening the agitation, the agglomeration cannot be stopped by relying on the agitation force, so the amount of terminator (Na) used must be increased. By increasing the amount of Na used, the agglomeration state of the resin particles can be controlled, undesired fusion of resin particles can be prevented, and the particle size distribution can be improved. From the above, in the resin particles of the present invention, the Mg content (mass %) in the resin particles measured by fluorescent X-ray analysis is lower than the Na content (mass %). Furthermore, if the stirring is strong during the flocculation process, the amount of flocculant increases, the liquid temperature rises, and the stirring time becomes longer. Since the terminator can stop the flocculation by stirring, the amount of terminator used decreases. For these reasons, when the stirring is strong, the flocculant (Mg) is more than the terminator (Na).

[0008] (Measurement method) In the present invention, the X-ray fluorescence analysis may be performed, for example, by quantitatively analyzing metal ions using an X-ray fluorescence analyzer (ZSX Primus IV (Rigaku Corporation)). The form of the resin particle sample to be measured is not particularly limited, but molding the sample into pellets or sheets using a general pressure molding machine or the like makes it easier to handle. For example, a sample is placed in a tablet molding die with a diameter of 15 mm and pressed under a load of 6 MPa for 1 minute to obtain a pellet tablet of resin particles with a thickness of approximately 2 mm. The obtained pellet tablet is placed in the sample holder of the X-ray fluorescence analyzer, and quantitative analysis (tube voltage 50 kV, tube current 30 mA) is performed to detect the metal elements contained in the sample. If an external additive is added to the resin particles, the external additive is removed from the resin particles and the amount of metal element is measured. Any method can be used to remove the external additive. For example, 3.75 g of resin particles are added to 50 ml of a surfactant (Noigen ET-165) diluted to 0.5% and stirred in a ball mill. After that, ultrasonic energy (40 W, 5 minutes) is applied using an ultrasonic homogenizer. The ultrasonically treated resin dispersion solution is centrifuged and then filtered to recover the precipitate. The above process is repeated until the supernatant liquid after centrifugation becomes transparent. The sample is then dried in a thermostatic bath and the amount of metal elements is measured.

[0009] (2) In one embodiment of the present invention, the resin particles are the resin particles according to (1) above, characterized in that the Mg content is 0.05 mass % or more and 0.30 mass % or less with respect to the entire resin particles. Mg is an aggregating agent, and if the resin particles form a core-shell structure, at a concentration of 0.05 mass% or more, the particle size distribution of the core particles becomes sharp during the core aggregation process in the emulsion aggregation method. Furthermore, shell formation to the core is likely to occur during the shell aggregation process. At a concentration of 0.30 mass% or less, the aggregating properties become moderate during the core aggregation process, making it easier to adjust the particle size distribution and resulting in a sharp particle size distribution. Furthermore, hetero-aggregation to the core is more likely to occur during the shell aggregation process, making it less likely for homo-aggregation between shells to occur, preventing poor shell formation. (amount) The Mg content of the resin particles is preferably 0.1 mass % or more and 0.25 mass % or less, and more preferably 0.12 mass % or more and 0.20 mass % or less. (kinds) Mg is a divalent flocculant. Other flocculants include monovalent Na and K, and trivalent Al. However, monovalent Na and K have inferior flocculation properties compared to divalent Mg, and require a larger amount for flocculation. Also, particle size control can be difficult. Trivalent Al has too strong aggregating properties, making particle size control difficult. This tendency is particularly pronounced in systems with weak agitation.

[0010] (3) In one embodiment of the present invention, the resin particles are the resin particles described in (1) or (2) above, characterized in that the Na content is 0.10 mass% or more and 0.40 mass% or less with respect to the entire resin particles. Na is a terminator, and if it is 0.10 mass% or more, it can effectively stop aggregation. If it is 0.40 mass% or less, shape control during fusion is good. In addition, by suppressing the increase in the total metal amount, the risk of adverse effects on resistance and charging can be reduced. (amount) The Na content of the resin particles is preferably 0.15 mass % or more and 0.35 mass % or less, and more preferably 0.20 mass % or more and 0.30 mass % or less. The total of the Mg content (mass%) and the Na content (mass%) is preferably 0.20 to 0.80 mass%, and more preferably 0.20 to 0.42 mass%. (kinds) In contrast to the divalent Mg that is the flocculating agent, a monovalent metal is better as the terminator, and Na is preferred.

[0011] (4) In one embodiment of the present invention, the resin particles are 14 The resin particles according to any one of (1) to (3) above are characterized in that they contain a C concentration of 10.8 pMC or more. (Radiocarbon isotopes 14 C concentration) Radiocarbon isotopes of resin particles according to one embodiment 14 C concentration (hereinafter referred to as “ 14 The carbon concentration (sometimes referred to as "carbon concentration") is 10.8 pMC or more, preferably 11 pMC or more, more preferably 20 pMC or more, and even more preferably 30 pMC or more. 14 When the carbon concentration is 10.8 pMC or more, it is generally considered to have a high biomass level, which will be described later, and this can reduce the burden on the environment. 14 C exists in nature (in the atmosphere) and is taken up by photosynthesis while plants are active, and exists in the atmosphere. 14 The 14C concentration is in equilibrium with the carbon concentration (107.5 pMC). However, once the organism ceases its life activities, the absorption of carbon through photosynthesis ceases, and the 14C concentration decreases in accordance with the 5,730-year half-life of 14C. Fossil resources derived from living organisms have been in existence for tens of thousands to hundreds of millions of years since the cessation of life activities, so the 14C concentration is barely detectable. Here, "pMC" stands for percent modern carbon, which is the carbon content of biomass in 1950. 14 C and 12 Ratio to C ( 14 C / 12 C) is defined as 100 pMC. 14 ( 14 C) Because concentrations are increasing year by year, it is stipulated that this value must be multiplied by a coefficient for correction. The correction coefficient to be used is the coefficient appropriate for that year. The aforementioned 14The C concentration can also be expressed as the biomass degree calculated by the following formula (1). Biomass ratio (%) = 14 C concentration (pMC) / 107.5×100...Equation (1) 14 A carbon concentration of 10.8 pMC or more means that the biomass ratio is 10% or more. A biomass ratio of 10% or more is a concentration that is desired from the perspective of carbon neutrality. 14 There are no particular limitations on the method for measuring the C concentration, and it can be selected appropriately depending on the purpose, but radiocarbon dating is particularly preferred. The procedure for radiocarbon dating involves burning resin particles, reducing the carbon dioxide (CO2) and obtaining graphite (C). 14 The carbon concentration is measured using an accelerator mass spectrometer (AMS, manufactured by BetaAnalytics). Measurement using AMS is disclosed in, for example, Japanese Patent No. 4050051.

[0012] (5) In one embodiment of the present invention, the resin particles are the resin particles according to any one of (1) to (4) above, characterized in that they contain polyethylene terephthalate (PET) or polybutylene terephthalate (PBT).

[0013] [PET or PBT] The PET or PBT contained in the resin particles according to one embodiment is contained in the resin particles mainly to reduce the environmental load.

[0014] There are no particular restrictions on the PET or PBT, and it can be selected appropriately depending on the purpose. For example, recycled products, off-specification fiber waste, or pellets can be used. However, from the viewpoint of reducing the environmental load, recycled products (hereinafter sometimes referred to as "recycled resin") processed into flakes are preferred. There are no particular limitations on the molecular weight distribution, composition, production method, and form when used of PET or PBT, and they can be appropriately selected depending on the purpose. The weight average molecular weight (Mw) of PET or PBT is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 30,000 to 100,000.

[0015] The methods for analyzing and calculating the content of PET or PBT in the resin particles are not particularly limited, and a general method for calculating the blending amount of PET can be used. For example, the PET or PBT content can be separated from the resin particles by gel permeation chromatography (GPC) or the like, and the mass ratio of the constituent components of the resin particles can be calculated by subjecting each separated component to the analytical method described below.

[0016] Quantitative analysis can also be performed by using gas chromatography / mass spectrometry (GC / MS) at 300°C with a reaction reagent (10% tetramethyl ammonium hydroxide (TMAH) / methanol solution) to estimate the main components from the soft decomposition of the ester bonds in the resin particles due to methylation, and drawing a calibration curve of the total ion current chromatogram (TICC) intensity.

[0017] Separation of each component by GPC can be carried out, for example, by the following method.

[0018] In GPC measurement using tetrahydrofuran (THF) as the mobile phase, the eluate is fractionated using a fraction collector or the like, and fractions corresponding to the desired molecular weight portion of the full integral of the elution curve are collected.

[0019] The combined eluate is concentrated and dried using an evaporator or the like, and the solid content is then dissolved in a heavy solvent such as deuterated chloroform or deuterated THF, 1 H-NMR measurement is performed, and the ratio of constituent monomers of the resin in the eluted components is calculated from the integral ratio of each element.

[0020] Alternatively, the eluate may be concentrated, hydrolyzed with sodium hydroxide or the like, and the decomposition products may be subjected to qualitative and quantitative analysis by high performance liquid chromatography (HPLC) or the like to calculate the proportion of constituent monomers.

[0021] The content of PET or PBT is not particularly limited and can be selected appropriately depending on the purpose, but is preferably 5 to 70 parts by mass, more preferably 10 to 50 parts by mass, per 100 parts by mass of resin particles. When the content of PET or PBT is 70 parts by mass or less per 100 parts by mass of resin particles, low-temperature fixability can be exhibited. When the content of PET or PBT is 5 parts by mass or more per 100 parts by mass of resin particles, the effect of reducing the environmental load can be exhibited, and the resin particles can have an excellent particle size distribution. The content of PET or PBT within the above more preferred range is advantageous in that it can achieve both a reduced environmental load of the resin particles and an improved particle size distribution.

[0022] Another example of a method for separating components contained in resin particles when analyzing resin particles according to one embodiment is described in detail below. First, 1 g of resin particles is placed in 100 mL of THF and stirred at 25°C for 30 minutes to obtain a solution containing the soluble components. The solution is then filtered through a 0.2 μm membrane filter to obtain the THF-soluble components of the resin particles. This is then dissolved in THF to prepare a sample for GPC measurement and injected into the GPC used to measure the molecular weight of each of the resins described above. Meanwhile, a fraction collector is placed at the GPC eluate outlet, and eluate is collected at predetermined counts, obtaining eluate at 5% area fractions from the start of the elution curve (the rise of the curve). Next, for each eluate, 30 mg of sample is dissolved in 1 mL of deuterated chloroform, and 0.05% by volume of tetramethylsilane (TMS) is added as a reference substance. The solution is filled into a 5 mm diameter glass tube for NMR measurement, and a spectrum is obtained using a nuclear magnetic resonance spectrometer (JNM-AL400 manufactured by JEOL Ltd.) at a temperature of 23 to 25°C, with 128 integrations. The monomer composition and constituent ratio of the PET resin and other components contained in the resin particles can be determined from the peak integral ratio of the obtained spectrum.

[0023] (6) In one embodiment of the present invention, the resin particles are the resin particles described in any one of (1) to (5), characterized in that they contain the polyethylene terephthalate or polybutylene terephthalate and a biomass-derived resin, and the polyethylene terephthalate or polybutylene terephthalate content of the resin particles is greater than the biomass-derived resin content.

[0024] (Biomass-derived resin) The resin particles according to one embodiment preferably contain a biomass-derived resin, which may be contained in at least one of an amorphous resin, a non-crystalline resin, and a crystalline resin, which will be described later. The biomass-derived resin is a resin containing a plant-derived compound as a raw material. The biomass-derived resin may be contained in a crystalline resin described below, an amorphous resin, or other components such as a release agent. The resin particles can adjust the ratio of petroleum-derived components to plant-derived components in the alcohol component and acid component constituting the resin particles, thereby adjusting the environmental compatibility ratio described below and the toner quality when the resin particles are applied to a toner. In recent years, there has been a strong demand for biomass-derived resins and other materials that are environmentally friendly while also improving their functionality as toners. Many petroleum-based resins contain aromatic ring structures in their constituent monomers. However, when low-temperature fixability is required for biomass-derived resins, aliphatic monomers without aromatic ring structures are often used in their constituent monomers. This creates significant structural differences, leading to the problem of poor particle size distribution during resin particle production. To address the above-mentioned problems, resin particles according to one embodiment contain PET or PBT having an aromatic ring structure, thereby improving environmental friendliness while reducing the structural differences between biomass-derived resins. Furthermore, when a metal salt is used to aggregate resin particles during production, using a trivalent or higher metal salt with a high degree of crosslinking tends to result in differences in aggregation properties and a poor particle size distribution. Mild aggregation using a divalent metal salt allows for the production of resin particles with a good particle size distribution. Therefore, the resin particles according to one embodiment can reduce the environmental load and have an excellent particle size distribution. As described above, the resin particles according to one embodiment preferably contain at least one of an amorphous resin, an amorphous resin, and a crystalline resin in addition to PET or PBT, and more preferably contain an amorphous resin, an amorphous resin, and a crystalline resin. The total content of the biomass-derived resin and PET or PBT relative to the total mass of the resin particles is preferably 50% by mass or more, more preferably 60% by mass or more, and even more preferably 80% by mass or more. As described above, the resin particles according to one embodiment contain PET or PBT and a biomass-derived resin, but it is preferable that the amount of PET or PBT is greater than the amount of biomass-derived resin.

[0025] (7) In one embodiment of the present invention, the resin particles are those described in any one of (1) to (6) above, which form a core-shell structure and the shell layer contains at least a sulfonate group. The inclusion of a sulfonate group is expected to have effects on charging performance and heat-resistant storage stability, and in this embodiment, it is preferable to use a polyester resin containing a sulfonate group.

[0026] (Sulfonate group-containing polyester resin) The alcohol and carboxylic acid used in the synthesis of the sulfonate group-containing polyester resin are not particularly limited.

[0027] (diol) Examples of the alkylene oxide adducts of bisphenols include aliphatic diols such as ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, 1,8-octanediol, 1,10-decanediol, and 1,12-dodecanediol; diols having an oxyalkylene group such as diethylene glycol, triethylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol, and polytetramethylene glycol; alicyclic diols such as 1,4-cyclohexanedimethanol and hydrogenated bisphenol A; alicyclic diols to which alkylene oxides such as ethylene oxide, propylene oxide, and butylene oxide have been added; bisphenols such as bisphenol A, bisphenol F, and bisphenol S; and alkylene oxide adducts of bisphenols such as bisphenols to which alkylene oxides such as ethylene oxide, propylene oxide, and butylene oxide have been added.

[0028] (dicarboxylic acid) The dicarboxylic acid is not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include aliphatic dicarboxylic acids, aromatic dicarboxylic acids, etc. Furthermore, water, lower (1 to 3 carbon atoms) alkyl esters, or halides of these may also be used. The aliphatic dicarboxylic acid is not particularly limited and can be appropriately selected depending on the purpose. Examples thereof include succinic acid, adipic acid, sebacic acid, dodecanedioic acid, maleic acid, and fumaric acid. The aromatic dicarboxylic acid is not particularly limited and can be appropriately selected depending on the purpose. Examples thereof include phthalic acid, isophthalic acid, terephthalic acid, and naphthalenedicarboxylic acid. Among these, aliphatic dicarboxylic acids having 4 to 12 carbon atoms are preferred. These dicarboxylic acids may be used alone or in combination of two or more.

[0029] (trivalent or higher acid or alcohol) The above-mentioned trivalent or higher valent acids or alcohols may also be used. There are no particular limitations and they can be appropriately selected depending on the purpose, and examples thereof include glycerin, trimethylolethane, trimethylolpropane (TMP), pentaerythritol, sorbitol, dipentaerythritol, trimellitic acid (TMA), and pyromellitic acid.

[0030] (Sulfonic acid-containing monomer) The sulfonate group-containing polyester resin is synthesized using a monomer containing a sulfonate group. Examples of the sulfonate group-containing monomer include aromatic sulfonate group-containing monomers and aliphatic sulfonate group-containing monomers. Among these, aromatic sulfonate group-containing monomers having a divalent or higher carboxylic acid are preferred. Examples of aromatic dicarboxylic acids having a sulfonate group include sulfonates of 5-sulfoisophthalic acid, 2-sulfoisophthalic acid, 4-sulfoisophthalic acid, 4-sulfo-2,6-naphthalenedicarboxylic acid, and ester-forming derivatives thereof [lower alkyl (C1-4) esters (methyl esters, ethyl esters, etc.), acid anhydrides, etc.]. Examples of aliphatic dicarboxylic acids having a sulfo group include sulfonates of sulfosuccinic acid and its ester-forming derivatives [lower alkyl (C1-4) esters (methyl ester, ethyl ester, etc.), acid anhydrides, etc.]. Examples of sulfonates include salts of alkali metals (lithium, sodium, potassium, etc.), salts of alkaline earth metals (magnesium, calcium, etc.), ammonium salts, amine salts such as mono-, di-, and tri-amines having a hydroxyalkyl (C2-4) group (organic amine salts such as mono-, di-, and tri-ethylamine, mono-, di-, and tri-ethanolamine, diethylethanolamine, etc.), quaternary ammonium salts of these amines, and combinations of two or more of these. Among these, 5-sulfoisophthalic acid salts are preferred, and 5-sulfoisophthalic acid sodium salt and 5-sulfoisophthalic acid potassium salt are particularly preferred.

[0031] (8) One embodiment of the manufacturing method of the present invention is a manufacturing method including the steps of: preparing a solution by dissolving or dispersing a resin in an organic solvent; adding water to the solution to invert the phase from a water-in-oil dispersion to an oil-in-water dispersion; and aggregating fine particles in the oil-in-water dispersion using a flocculant and terminating the aggregation at a predetermined time point using a terminator, wherein the flocculant is a divalent metal element, Mg.

[0032] (9) One embodiment of the production method of the present invention is the production method described in (8) above, characterized in that the terminator is a monovalent metal element, Na. (10) The present invention also provides a toner containing the resin particles described in any one of (1) to (7) above.

[0033] (amorphous resin) The resin particles according to one embodiment preferably contain an amorphous resin. The amorphous resin is preferably a terpene resin or an amorphous (non-crystalline) polyester resin (hereinafter also referred to as "amorphous polyester resin B"). Among them, a linear polyester resin is preferable, and an unmodified polyester resin is also preferable. In this embodiment, the amorphous resin refers to a resin excluding PET or PBT. The unmodified polyester resin is a polyester resin obtained using a polyhydric alcohol and a polycarboxylic acid or a derivative thereof, such as a polycarboxylic acid, a polycarboxylic acid anhydride, or a polycarboxylic acid ester, and is not modified with an isocyanate compound or the like. The amorphous polyester resin preferably does not contain a urethane bond or a urea bond. The amorphous polyester resin preferably contains a dicarboxylic acid component as a constituent, and the dicarboxylic acid component preferably contains 50 mol % or more of terephthalic acid, which is advantageous in terms of heat-resistant storage stability. Examples of polyhydric alcohols include diols. Examples of diols include alkylene (carbon number 2 to 3) oxide (average number of added moles 1 to 10) adducts of bisphenol A such as polyoxypropylene(2.2)-2,2-bis(4-hydroxyphenyl)propane and polyoxyethylene(2.2)-2,2-bis(4-hydroxyphenyl)propane; ethylene glycol, neopentyl glycol, propylene glycol; hydrogenated bisphenol A, and alkylene (carbon number 2 to 3) oxide (average number of added moles 1 to 10) adducts of hydrogenated bisphenol A. These may be used alone or in combination of two or more. Among these, plant-derived ethylene glycol and propylene glycol are preferred. Examples of polycarboxylic acids include dicarboxylic acids. Examples of dicarboxylic acids include adipic acid, phthalic acid, isophthalic acid, terephthalic acid, fumaric acid, maleic acid, succinic acids substituted with an alkyl group having 1 to 20 carbon atoms or an alkenyl group having 2 to 20 carbon atoms, such as dodecenylsuccinic acid and octylsuccinic acid, and modified purified rosin. Preferred modified purified rosins are those modified with acrylic acid, fumaric acid, and maleic acid. Among these, succinic acid, a saturated aliphatic acid derived from a plant, and modified purified rosin are preferred. Being derived from a plant can enhance carbon neutrality. Saturated aliphatic acids have the effect of enhancing the recrystallization properties of crystalline polyester resins, increasing the aspect ratio of the crystalline polyester resins, and improving low-temperature fixability. These may be used alone or in combination of two or more. Furthermore, for the purpose of adjusting the acid value and hydroxyl value, the amorphous polyester resin may contain at least one of a trivalent or higher carboxylic acid and a trivalent or higher alcohol at the end of its resin chain. Examples of trivalent or higher carboxylic acids include trimellitic acid, pyromellitic acid, and acid anhydrides thereof. Examples of trihydric or higher alcohols include glycerin, pentaerythritol, and trimethylolpropane.

[0034] The molecular weight of the amorphous polyester resin is not particularly limited and can be appropriately selected depending on the purpose. The weight average molecular weight (Mw) measured by gel permeation chromatography (GPC) is preferably 3,000 to 10,000. The number average molecular weight (Mn) is preferably 1,000 to 4,000. The ratio of the weight average molecular weight (Mw) to the number average molecular weight (Mn), Mw / Mn, is preferably 1.0 to 4.0. When the molecular weight is equal to or greater than the lower limit, it is possible to prevent the resin particles from having a reduced heat-resistant storage stability and a reduced durability against stress caused by stirring in a developing machine, etc. When the molecular weight is equal to or less than the upper limit, it is possible to prevent the resin particles from having an increased viscoelasticity when melted, and to prevent a reduced low-temperature fixability. The weight average molecular weight (Mw) is more preferably 4,000 to 7,000. The number average molecular weight (Mn) is more preferably 1,500 to 3,000. The ratio Mw / Mn of the weight average molecular weight (Mw) to the number average molecular weight (Mn) is more preferably 1.0 to 3.5.

[0035] The acid value of the amorphous polyester resin is not particularly limited and can be appropriately selected depending on the purpose. It is preferably 1 mgKOH / g to 50 mgKOH / g, and more preferably 5 mgKOH / g to 30 mgKOH / g. An acid value of 1 mgKOH / g or more makes the resin particles more likely to be negatively charged, and further improves the affinity between the paper and the resin particles during fixation to paper, thereby improving low-temperature fixability. An acid value of 50 mgKOH / g or less can prevent a decrease in charging stability, particularly charging stability against environmental changes. The hydroxyl value of the amorphous polyester resin is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 5 mgKOH / g or more.

[0036] The glass transition temperature (Tg) of the amorphous polyester resin is preferably 40°C to 80°C, more preferably 50°C to 70°C. When the glass transition temperature (Tg) is 40°C or higher, the resin particles have sufficient heat-resistant storage stability and durability against stress such as stirring in a developing machine, and also have good filming resistance. When the glass transition temperature (Tg) is 80°C or lower, the resin particles are sufficiently resistant to deformation due to heat and pressure during fixing, and good low-temperature fixability is achieved.

[0037] The molecular structure of the amorphous polyester resin can be confirmed by NMR measurement in solution or solid, as well as X-ray diffraction, GC / MS, LC / MS, and IR measurement. -1 and 990±10cm -1 One method is to detect amorphous polyester resins that do not have absorption due to olefin δCH (out-of-plane bending vibration).

[0038] The content of the amorphous resin is not particularly limited and can be selected appropriately depending on the purpose, but is preferably 50 to 90 parts by weight, and more preferably 60 to 80 parts by weight, per 100 parts by weight of resin particles. A content of 50 parts by weight or more can prevent deterioration of the dispersibility of the pigment and release agent in the resin particles, thereby preventing image fogging and distortion. A content of 90 parts by weight or less can prevent a decrease in the contents of, for example, the following crystalline polyester resin C and amorphous polyester resin B, and suppress a decrease in low-temperature fixability. A content within the above-mentioned more preferred range is advantageous in that both high image quality and low-temperature fixability are excellent.

[0039] (prepolymer) The resin particles according to one embodiment may contain an amorphous resin (prepolymer) as the amorphous resin in order to improve low-temperature fixability, and the prepolymer is preferably modified with an isocyanate compound or the like. Reactive precursors include polyesters having groups capable of reacting with active hydrogen groups. Examples of the group capable of reacting with the active hydrogen group include an isocyanate group, an epoxy group, a carboxylic acid, an acid chloride group, etc. Among these, an isocyanate group is preferred because it can introduce a urethane bond or a urea bond into the amorphous polyester resin. The reactive precursor may have a branched structure imparted by at least one of a trivalent or higher alcohol and a trivalent or higher carboxylic acid. The polyester resin containing an isocyanate group is, for example, a polyester resin having an active hydrogen group. Examples include a reaction product of a polyester resin and a polyisocyanate (hereinafter, sometimes referred to as amorphous polyester resin A).

[0040] The polyester resin having an active hydrogen group can be obtained, for example, by polycondensation of a diol, a dicarboxylic acid, and at least one of a trivalent or higher alcohol and a trivalent or higher carboxylic acid. The trivalent or higher alcohol and the trivalent or higher carboxylic acid impart a branched structure to the polyester resin containing an isocyanate group. Examples of diols include aliphatic diols such as ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, 2-methyl-1,3-propanediol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, 1,8-octanediol, 1,10-decanediol, and 1,12-dodecanediol; diethylene glycol, triethylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol, and polytetramethyl Examples of suitable diols include diols having an oxyalkylene group such as ethylene glycol; alicyclic diols such as 1,4-cyclohexanedimethanol and hydrogenated bisphenol A; alicyclic diols to which alkylene oxides such as ethylene oxide, propylene oxide, and butylene oxide have been added; bisphenols such as bisphenol A, bisphenol F, and bisphenol S; and alkylene oxide adducts of bisphenols, such as bisphenols to which alkylene oxides such as ethylene oxide, propylene oxide, and butylene oxide have been added. Among these, from the viewpoint of controlling the glass transition temperature (Tg) of the amorphous polyester resin A to 20° C. or less, it is preferable to use aliphatic diols having 3 to 10 carbon atoms, such as 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, 2-methyl-1,3-propanediol, 1,5-pentanediol, and 3-methyl-1,5-pentanediol, and it is more preferable to use 50 mol% or more of the alcohol component in the resin. These diols may be used alone or in combination of two or more.

[0041] The amorphous polyester resin A has steric hindrance in the resin chain, which reduces the melt viscosity during fixing and makes it easier to achieve low-temperature fixability. For this reason, the main chain of the aliphatic diol preferably has a structure represented by the following general formula (1): HO-(CR1R2)n-OH General formula (1) where R1 and R2 each independently represent a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and n represents an odd number from 3 to 9. In the n repeating units, R1 and R2 may be the same or different. Here, the main chain of an aliphatic diol refers to the carbon chain that connects two hydroxyl groups of the aliphatic diol with the shortest number of carbon atoms. When the main chain has an odd number of carbon atoms, the crystallinity decreases due to the odd-even ratio, which is preferable. Furthermore, when the main chain has at least one alkyl group having 1 to 3 carbon atoms in the side chain, the interaction energy between the main chain molecules decreases due to the stericity, which is more preferable.

[0042] Examples of dicarboxylic acids include aliphatic dicarboxylic acids such as succinic acid, adipic acid, sebacic acid, dodecanedioic acid, maleic acid, and fumaric acid; and aromatic dicarboxylic acids such as phthalic acid, isophthalic acid, terephthalic acid, and naphthalenedicarboxylic acid. Furthermore, anhydrides, lower (C1-C3) alkyl esters, and halides of these dicarboxylic acids may also be used. Among these, aliphatic dicarboxylic acids having from 4 to 12 carbon atoms are preferred from the viewpoint of controlling the glass transition temperature (Tg) of the amorphous polyester resin A to 20°C or less, and it is more preferable to use them in an amount of 50% by mass or more of the carboxylic acid components in the resin. These dicarboxylic acids may be used alone or in combination of two or more.

[0043] Examples of trihydric or higher alcohols include trihydric or higher aliphatic alcohols such as glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, and sorbitol; trihydric or higher polyphenols such as trisphenol PA, phenol novolac, and cresol novolac; and alkylene oxide adducts of trihydric or higher polyphenols, such as those obtained by adding alkylene oxides such as ethylene oxide, propylene oxide, and butylene oxide to trihydric or higher polyphenols.

[0044] Examples of trivalent or higher carboxylic acids include trivalent or higher aromatic carboxylic acids, and particularly preferred are trivalent or higher aromatic carboxylic acids having 9 to 20 carbon atoms, such as trimellitic acid and pyromellitic acid. Furthermore, anhydrides, lower (1 to 3 carbon atoms) alkyl esters, and halides of these may also be used.

[0045] Examples of polyisocyanates include diisocyanates and tri- or higher valent isocyanates. The polyisocyanate is not particularly limited and can be appropriately selected depending on the purpose. Examples of the polyisocyanate include 1,3- and / or 1,4-phenylene diisocyanate, 2,4- and / or 2,6-tolylene diisocyanate (TDI), crude TDI, 2,4'- and / or 4,4'-diphenylmethane diisocyanate (MDI), crude MDI [crude diaminophenylmethane [condensation product of formaldehyde and aromatic amine (aniline) or a mixture thereof; diaminodiphenylmethane and a small amount (for example, 5 to 20% by mass) of a trifunctional or higher functional group], Phosgenates of polyallyl polyisocyanate (PAPI), aromatic diisocyanates such as 1,5-naphthylene diisocyanate, 4,4',4"-triphenylmethane triisocyanate, m- and p-isocyanatophenylsulfonyl isocyanate; ethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate (HDI), dodecamethylene diisocyanate, 1,6,11-undecane triisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, Aliphatic diisocyanates such as isocyanate, lysine diisocyanate, 2,6-diisocyanatomethyl caproate, bis(2-isocyanatoethyl) fumarate, bis(2-isocyanatoethyl) carbonate, 2-isocyanatoethyl-2,6-diisocyanatohexanoate; isophorone diisocyanate (IPDI), dicyclohexylmethane-4,4'-diisocyanate (hydrogenated MDI), cyclohexylene diisocyanate, methylcyclohexylene diisocyanate (hydrogenated TDI), bis(2-isocyanatoethyl) alicyclic diisocyanates such as m- and p-xylylene diisocyanate (XDI) and α,α,α',α'-tetramethylxylylene diisocyanate (TMXDI); trivalent or higher polyisocyanates such as lysine triisocyanate and diisocyanate-modified products of trivalent or higher alcohols; and modified products of these isocyanates, and mixtures of two or more of these may also be used.Examples of the modified isocyanate include modified products containing a urethane group, a carbodiimide group, an allophanate group, a urea group, a biuret group, a uretdione group, a uretoimine group, an isocyanurate group, and an oxazolidone group.

[0046] (crystalline resin) In one embodiment, a crystalline resin is preferably added to the resin particles in order to improve low-temperature fixability.

[0047] The crystalline resin is not particularly limited as long as it has crystallinity and can be appropriately selected depending on the purpose. Examples include polyester resin, polyurethane resin, polyurea resin, polyamide resin, polyether resin, vinyl resin, modified crystalline resin, etc. These may be used alone or in combination of two or more.

[0048] The polyester resin used in the crystalline resin is a crystalline polyester resin (hereinafter, may be referred to as "crystalline polyester resin C"). Crystalline polyester resin C will be described below.

[0049] Crystalline polyester resin C has high crystallinity and therefore exhibits heat melting characteristics that result in a sudden change in viscosity near the fixing start temperature. Resin particles having good heat-resistant storage stability and low-temperature fixability can be obtained by using crystalline polyester resin C having such properties together with amorphous polyester resin B. For example, by using them together, the heat-resistant storage stability is good due to the crystallinity up to just before the melting start temperature, and at the melting start temperature, the crystalline polyester resin C melts, causing a sudden decrease in viscosity (sharp melt property), which in turn makes it compatible with the amorphous polyester resin B described above, and both resins rapidly decrease in viscosity, allowing for good fixation.

[0050] (crystalline polyester resin) The crystalline polyester resin is obtained from a polyhydric alcohol and a polycarboxylic acid or a derivative thereof, such as a polycarboxylic acid, a polycarboxylic acid anhydride, or a polycarboxylic acid ester.

[0051] In this embodiment, the crystalline polyester resin refers to a resin obtained by using a polyhydric alcohol and a polycarboxylic acid or a derivative thereof, such as a polycarboxylic acid, a polycarboxylic acid anhydride, or a polycarboxylic acid ester, as described above. Modified polyester resins, such as prepolymers, and resins obtained by subjecting such prepolymers to a crosslinking and / or elongation reaction, do not fall under the category of crystalline polyester resins.

[0052] ((Polyhydric alcohol)) The polyhydric alcohol is not particularly limited and can be appropriately selected depending on the purpose. Examples thereof include diols and trihydric or higher alcohols.

[0053] Examples of diols include saturated aliphatic diols. Examples of the saturated aliphatic diols include linear saturated aliphatic diols and branched saturated aliphatic diols. Among these, linear saturated aliphatic diols are preferred, and linear saturated aliphatic diols having 2 to 12 carbon atoms are more preferred. If the saturated aliphatic diol is branched, the crystallinity of the crystalline polyester resin may decrease, resulting in a lower melting point. Furthermore, if the saturated aliphatic diol has more than 12 carbon atoms, it may be difficult to obtain a practical material.

[0054] Examples of the saturated aliphatic diol 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, 1,14-tetradecanediol, 1,18-octadecanediol, 1,14-eicosanedecanediol, etc. Among these, ethylene glycol, 1,4-butanediol, 1,6-hexanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, and 1,12-dodecanediol are preferred in terms of the high crystallinity and excellent sharp melt properties of the crystalline polyester resin.

[0055] Examples of trihydric or higher alcohols include glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, etc. These may be used alone or in combination of two or more.

[0056] ((Polycarboxylic acid)) The polycarboxylic acid is not particularly limited and can be appropriately selected depending on the purpose. Examples thereof include dicarboxylic acids and tricarboxylic or higher carboxylic acids.

[0057] Examples of dicarboxylic acids include saturated aliphatic dicarboxylic acids such as oxalic acid, succinic acid, glutaric acid, adipic acid, suberic acid, azelaic acid, sebacic acid, 1,9-nonanedicarboxylic acid, 1,10-decanedicarboxylic acid, 1,12-dodecanedicarboxylic acid, 1,14-tetradecanedicarboxylic acid, and 1,18-octadecanedicarboxylic acid; and aromatic dicarboxylic acids such as phthalic acid, isophthalic acid, terephthalic acid, naphthalene-2,6-dicarboxylic acid, malonic acid, and mesaconic acid. Further examples include anhydrides of these dicarboxylic acids and their lower (1 to 3 carbon atoms) alkyl esters. Among these, saturated aliphatic dicarboxylic acids derived from plants and having 12 or fewer carbon atoms are preferred from the viewpoint of carbon neutrality.

[0058] Examples of trivalent or higher carboxylic acids include 1,2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, and the like, as well as anhydrides and lower (C1 to C3) alkyl esters of these.

[0059] These may be used alone or in combination of two or more.

[0060] The crystalline polyester resin is preferably composed of a linear saturated aliphatic dicarboxylic acid having 4 to 12 carbon atoms and a linear saturated aliphatic diol having 2 to 12 carbon atoms. This results in high crystallinity and excellent sharp melting properties, allowing for excellent low-temperature fixability. One method for controlling the crystallinity and softening point of the crystalline polyester resin is to design and use a non-linear polyester obtained by condensation polymerization of a trivalent or higher polyhydric alcohol such as glycerin to the alcohol component or a trivalent or higher polycarboxylic acid such as trimellitic anhydride to the acid component during polyester synthesis.

[0061] The molecular structure of crystalline polyester resin can be confirmed by NMR measurement of solution or solid, X-ray diffraction, GC / MS, LC / MS, IR measurement, etc., but it can be easily confirmed by infrared absorption spectroscopy at 965±10cm -1 Or 990±10cm -1 Examples include those that have absorption based on the δCH (out-of-plane bending vibration) of olefins.

[0062] Regarding molecular weight, a polymer with a sharp molecular weight distribution and low molecular weight has excellent low-temperature fixability, while a high content of low-molecular-weight components leads to poor heat-resistant storage stability. From this perspective, it is preferable that the molecular weight distribution of the o-dichlorobenzene-soluble fraction measured by GPC, in which the horizontal axis is log(M) and the vertical axis is mass%, has a peak position in the range of 3.5 to 4.0, a peak half-width of 1.5 or less, a weight-average molecular weight (Mw) of 3,000 to 30,000, a number-average molecular weight (Mn) of 1,000 to 10,000, and a ratio Mw / Mn of 1 to 10. Even more preferable is a weight-average molecular weight (Mw) of 5,000 to 15,000, a number-average molecular weight (Mn) of 2,000 to 10,000, and a ratio Mw / Mn of 1 to 5.

[0063] The acid value of the crystalline polyester resin is preferably 5 mgKOH / g or more to achieve the desired low-temperature fixability from the viewpoint of the affinity between the resin and paper. For the preparation of fine particles by the phase inversion emulsification method, the acid value of the crystalline polyester resin is more preferably 7 mgKOH / g or more. On the other hand, for improving hot offset resistance, the acid value of the crystalline polyester resin is preferably 45 mgKOH / g or less. The hydroxyl value of the crystalline polyester resin is preferably 0 to 50 mgKOH / g, more preferably 5 to 50 mgKOH / g, in order to achieve a predetermined low-temperature fixability and good charging characteristics.

[0064] The content of the crystalline polyester resin is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 5 to 30 parts by mass per 100 parts by mass of resin particles.

[0065] (Other ingredients) The resin particles according to an embodiment may contain other components, such as wax, external additives, colorants, charge control agents, cleaning improvers, and magnetic materials.

[0066] (wax) The wax is not particularly limited and can be selected appropriately depending on the purpose, but a low-melting release agent with a melting point of 50° C. to 120° C. is preferred. The low-melting release agent, when dispersed in the resin, effectively acts as a release agent at the interface between the fixing roller and the resin particles, thereby improving hot offset resistance even in an oil-less fixing roller (wherein a release agent such as oil is not applied to the fixing roller).

[0067] Suitable examples of release agents include waxes. Examples of waxes include natural waxes such as plant-based waxes such as carnauba wax, cotton wax, Japan wax, and rice wax; animal-based waxes such as beeswax and lanolin; mineral waxes such as ozokerite and cerusine; and petroleum waxes such as paraffin, microcrystalline wax, and petrolatum. In addition to these natural waxes, synthetic hydrocarbon waxes such as Fischer-Tropsch wax and polyethylene wax; and synthetic waxes such as esters, ketones, and ethers. Other examples include fatty acid amides such as 12-hydroxystearic acid amide, stearic acid amide, phthalimide anhydride, and chlorinated hydrocarbons; low-molecular-weight crystalline polymer resins such as polyacrylate homopolymers or copolymers (e.g., n-stearyl acrylate-ethyl methacrylate copolymers); and crystalline polymers having long alkyl groups in their side chains. These may be used alone or in combination of two or more. From the viewpoint of reducing the environmental load, vegetable waxes are preferred.

[0068] The melting point of the wax is not particularly limited and can be selected appropriately depending on the purpose, but is preferably 50°C to 120°C, more preferably 60°C to 90°C. A melting point of 50°C or higher can prevent the wax from adversely affecting heat-resistant storage stability, while a melting point of 120°C or lower can effectively prevent the problem of cold offset occurring during low-temperature fixing. The melt viscosity of the wax, measured at a temperature 20°C higher than the melting point of the wax, is preferably 5 cps to 1,000 cps, more preferably 10 cps to 100 cps. A melt viscosity of 5 cps or higher can prevent a decrease in release properties, while a melt viscosity of 1,000 cps or lower can fully exhibit the effects of hot offset resistance and low-temperature fixability. The content of the wax in the resin particles is not particularly limited and can be selected appropriately depending on the purpose, but is preferably 0% to 40% by mass, more preferably 3% to 30% by mass.

[0069] (external additives) As the external additive, inorganic fine particles, polymer fine particles, etc. can be used.

[0070] Examples of inorganic fine particles include silica, alumina, titanium oxide, barium titanate, magnesium titanate, calcium titanate, strontium titanate, iron oxide, copper oxide, zinc oxide, tin oxide, silica sand, clay, mica, wollastonite, diatomaceous earth, chromium oxide, cerium oxide, red iron oxide, antimony trioxide, magnesium oxide, zirconium oxide, barium sulfate, barium carbonate, calcium carbonate, silicon carbide, silicon nitride, etc. Among these, silica, alumina, and titanium oxide are preferred.

[0071] The inorganic fine particles may be surface-treated with a hydrophobic treatment agent to enhance their hydrophobicity and prevent deterioration of flowability and charging properties even under high humidity. Preferred examples of the hydrophobic treatment agent include silane coupling agents, silylating agents, silane coupling agents having a fluorinated alkyl group, organic titanate coupling agents, aluminum coupling agents, silicone oils, and modified silicone oils.

[0072] Examples of polymeric fine particles include polystyrene obtained by soap-free emulsion polymerization, suspension polymerization, or dispersion polymerization, methacrylic acid ester or acrylic acid ester copolymers, polycondensation systems such as silicone, benzoguanamine, and nylon, and polymer particles made from thermosetting resins. The average particle size of the primary particles of the inorganic fine particles is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 5 nm to 2 μm, and more preferably 10 nm to 500 nm. If the average particle size is 5 nm or more, aggregation of the inorganic fine particles is suppressed, and the inorganic fine particles can be uniformly dispersed in the resin particles. If the average particle size is 2 μm or less, the filler effect improves the heat-resistant storage stability.

[0073] The average particle size is a value obtained by directly determining the particle size from a photograph obtained by a transmission electron microscope, and it is preferable to observe at least 100 particles and use the average value of the major diameters thereof.

[0074] The specific surface area of ​​the external additive by the BET method is 20 to 500 m 2 / g is preferred.

[0075] The content of the external additive is preferably 0.01% by mass to 5% by mass of the resin particles.

[0076] (coloring agent) As the colorant, known dyes and pigments can be used, for example, carbon black, nigrosine dye, iron black, naphthol yellow S, Hansa yellow (10G, 5G, G), cadmium yellow, yellow iron oxide, yellow ochre, yellow lead, titanium yellow, polyazo yellow, oil yellow, Hansa yellow (GR, A, RN, R), pigment yellow L, benzidine yellow (G, GR), permanent yellow (NCG), Balkan fast yellow (5G, R), tartrazine lake, quinoline yellow lake, anthrazan yellow BGL, isoindolinone yellow -, red iron oxide, red lead, vermilion lead, cadmium red, cadmium mercury red, antimony vermilion, permanent red 4R, para red, faise red, parachlor orthonitroaniline red, Lithol Fast Scarlet G, Brilliant Fast Scarlet, Brilliant Carmine BS, permanent red (F2R, F4R, FRL, FRLL, F4RH), Fast Scarlet VD, Belcan Fast Rubin B, Brilliant Scarlet G, Lithol Rubin GX, permanent red F5R, Brilliant Carmine 6B, POG Mentos Scarlet 3B, Bordeaux 5B, Toluidine Maroon, Permanent Bordeaux F2K, Helio Bordeaux BL, Bordeaux 10B, Bon Maroon Light, Bon Maroon Medium, Eosin Lake, Rhodamine Lake B, Rhodamine Lake Y, Alizarin Lake, Thioindigo Red B, Thioindigo Maroon, Oil Red, Quinacridone Red, Pyrazolone Red, Polyazo Red, Chrome Vermilion, Benzidine Orange, Perinone Orange, Oil Orange, Cobalt Blue, Cerulean Blue, Alkaline Blue Lake, Peacock Blue Lake, Victoria Blue Lake, Metal-free Phthalocyanine Blue, Phthalocyanine Blue, Fast Sky Blue, Indanthrene Blue (RS, BC), Indigo, Ultramarine, Prussian Blue, Anthraquinone Blue, Fast Violet B, Methyl Violet Lake, Cobalt Purple, Manganese Purple, Dioxane Violet, Anthraquinone Violet, Chrome Green, Zinc Green, Chromium Oxide, Pyridian, Emerald Green, Pigment Green B, Naphthol Green B, Green Gold, Acid Green Lake, Malachite Green Lake,Phthalocyanine green, anthraquinone green, titanium oxide, zinc oxide, lithopone, and mixtures thereof can be used.

[0077] (Charge control agent) The charge control agent may be a general charge control agent, such as nigrosine dyes, triphenylmethane dyes, chromium-containing metal complex dyes, molybdate chelate pigments, rhodamine dyes, alkoxyamines, quaternary ammonium salts (including fluorine-modified quaternary ammonium salts), alkylamides, phosphorus simple substance or compounds, tungsten simple substance or compounds, fluorine-based activators, metal salicylate salts, and metal salts of salicylic acid derivatives. Specifically, these include the nigrosine dye Bontron 03, the quaternary ammonium salt Bontron P-51, the metal-containing azo dye Bontron S-34, the oxynaphthoic acid metal complex E-82, the salicylic acid metal complex E-84, and the phenol condensate E-89 (all manufactured by Orient Chemical Industry Co., Ltd.), the quaternary ammonium salt molybdenum complexes TP-302 and TP-415 (both manufactured by Hodogaya Chemical Co., Ltd.), the quaternary ammonium salt Copy Charge PSY VP2038, the triphenylmethane derivative Copy Blue PR, and the quaternary ammonium salt Copy Charge NEG VP2036 and Copy Charge NX. Examples include VP434 (all manufactured by Hoechst), LRA-901, the boron complex LR-147 (manufactured by Nippon Carlit), copper phthalocyanine, perylene, quinacridone, azo pigments, and other polymeric compounds having functional groups such as sulfonic acid groups, carboxyl groups, and quaternary ammonium salts.The charge control agent may be used in an amount that allows it to exhibit its performance without interfering with fixation properties, etc., and is contained in the resin particles in an amount of 0.5% to 5% by weight, and preferably 0.8% to 3% by weight.

[0078] (cleaning improver) The cleaning property improver is not particularly limited as long as it is added to resin particles to remove the developer remaining on the photosensitive member or primary transfer medium after transfer, and can be appropriately selected depending on the purpose. Examples of the cleaning property improver include fatty acid metal salts such as zinc stearate, calcium stearate, and stearic acid, and polymer fine particles produced by soap-free emulsion polymerization, such as polymethyl methacrylate fine particles and polystyrene fine particles. The polymer fine particles preferably have a relatively narrow particle size distribution, and are preferably those with a volume average particle size of 0.01 μm to 1 μm.

[0079] (Magnetic material) The magnetic material is not particularly limited and can be appropriately selected from known materials depending on the purpose, and examples thereof include iron powder, magnetite, ferrite, etc. Among these, white materials are preferred in terms of color tone.

[0080] <Characteristics of resin particles> (Particle diameter of resin particles) The particle size of resin particles according to one embodiment is measured using a Coulter Multisizer III (manufactured by Coulter). The particle size of resin particles is measured as follows: First, 2 mL of a surfactant (sodium dodecylbenzenesulfonate, manufactured by Tokyo Chemical Industry Co., Ltd.) is added as a dispersant to 100 mL of electrolyte. The electrolyte is prepared by using first-grade sodium chloride to prepare an approximately 1% NaCl aqueous solution, and ISOTON-II (manufactured by Coulter) can be used. 10 mg of a measurement sample (solid content) is added to the mixture of the electrolyte and surfactant to obtain an electrolyte solution in which the sample is suspended. The electrolyte solution in which the sample is suspended is dispersed using an ultrasonic disperser for approximately 1 to 3 minutes, and the volume and number of resin particles are measured using a Coulter Multisizer III with a 100 μm aperture, and the volume distribution and number distribution are calculated. The volume average particle size (Dv) and number average particle size (Dn) of the resin particles are determined from the obtained distributions. In the present invention, the volume average particle diameter (Dv) of the resin particles is preferably 4.5 to 7.5 μm, more preferably 5.0 to 6.0 μm, and the ratio Dv / Dn of the volume average particle diameter (Dv) to the number average particle diameter (Dn) of the resin particles is preferably 1.15 to 1.35, more preferably 1.20 to 1.30.

[0081] [Measuring method for melting point and glass transition temperature (Tg)] The melting point and glass transition temperature (Tg) of the resin particles according to one embodiment can be measured using, for example, a DSC system (differential scanning calorimeter) ("Q-200" manufactured by TA Instruments). Specifically, the melting point and glass transition temperature of a target sample can be measured by the following procedure. First, approximately 5.0 mg of the target sample is placed in an aluminum sample container, which is then placed on a holder unit and set in an electric furnace. Next, in a nitrogen atmosphere, the sample is heated from -80°C to 150°C at a heating rate of 10°C / min (first heating). Thereafter, the sample is cooled from 150°C to -80°C at a heating rate of 10°C / min, and further heated to 150°C at a heating rate of 10°C / min (second heating). During each of the first and second heatings, a DSC curve is measured using a differential scanning calorimeter ("Q-200" manufactured by TA Instruments). From the obtained DSC curves, the DSC curve at the first temperature rise can be selected using the analysis program in the Q-200 system, and the glass transition temperature (Tg) of the target sample at the first temperature rise can be determined. Similarly, the DSC curve at the second temperature rise can be selected, and the glass transition temperature (Tg) of the target sample at the second temperature rise can be determined.

[0082] Furthermore, the DSC curve obtained during the first heating run can be selected using the analysis program in the Q-200 system, and the endothermic peak top temperature during the first heating run of the target sample can be determined as the melting point. Similarly, the DSC curve during the second heating run can be selected, and the endothermic peak top temperature during the second heating run of the target sample can be determined as the melting point.

[0083] Furthermore, in this specification, unless otherwise specified, the glass transition temperature (Tg) and melting point of amorphous polyester resin A, amorphous polyester resin B, crystalline polyester resin C, and other constituent components such as a release agent are the endothermic peak top temperature and glass transition temperature (Tg) at the time of the second temperature rise, respectively, as the melting point and glass transition temperature (Tg) of each target sample.

[0084] [Average particle size, average circularity] The average particle size and average circularity can also be measured using, for example, a flow particle image analyzer (FPIA-3000, manufactured by Sysmex Corporation). Specifically, 0.1 to 0.5 ml of a surfactant, preferably an alkylbenzene sulfonate, is added as a dispersant to 100 to 150 ml of water from which solid impurities have been removed, and approximately 0.1 to 0.5 g of the sample to be measured is then added. The suspension containing the dispersed sample is subjected to a dispersion treatment using an ultrasonic disperser for approximately 1 to 3 minutes, and the dispersion concentration is adjusted to 3,000 particles / μl to 10,000 particles / μl. The average particle size and average circularity are measured using the flow particle image analyzer. The particle size is the equivalent circle diameter, and the average particle size is determined based on the equivalent circle diameter (number basis). The analysis conditions for the flow particle image analyzer are as follows: Particle size limit: 0.5 μm≦circle equivalent diameter (number basis)≦200.0 μm Particle shape limit: 0.93<circularity≦1.00 The average circularity is defined as follows. (Average circularity) = (perimeter of a circle equal to the projected area) / (perimeter of the projected image) In the present invention, the average circularity of the resin particles is preferably from 0.960 to 0.975, and more preferably from 0.964 to 0.970.

[0085] [Molecular weight measurement] The molecular weight of each component of the resin particles can be measured, for example, by the following method. Gel permeation chromatography (GPC) measurement device: GPC-8220GPC (Manufactured by Tosoh Corporation) Column: TSKgel SuperHZM-H 15cm triple column (Tosoh Corporation) ·Temperature: 40℃ Solvent: THF ·Flow rate: 0.35mL / min Sample: 100 μL of 0.15% by mass sample injected Sample pretreatment: Resin particles are dissolved in tetrahydrofuran (THF) (containing stabilizers, manufactured by Wako Pure Chemical Industries, Ltd.) at 0.15% by mass, then filtered through a 0.2 μm filter. The filtrate is used as the sample. 100 μL of the THF sample solution is injected and measured.

[0086] When measuring the molecular weight of a sample, the molecular weight distribution of the sample is calculated from the relationship between the logarithm of the calibration curve prepared using several monodisperse polystyrene standard samples and the count number. The standard polystyrene samples used to prepare the calibration curve are Showdex STANDARD (Showa Denko K.K.), Std. Nos. S-7300, S-210, S-390, S-875, S-1980, S-10.9, S-629, S-3.0, and S-0.580. An RI (refractive index) detector is used.

[0087] <Method of manufacturing resin particles> A method for producing resin particles according to an embodiment will be described. The method for producing resin particles according to an embodiment includes an oil phase preparation step, an aqueous phase preparation step, a phase inversion emulsification step, a solvent removal step, an aggregation step, and a fusion step, and may further include other steps such as a shell formation step, a washing step, a drying step, an annealing step, and an external addition step, as necessary.

[0088] (Oil phase preparation process) In the oil phase preparation step, the resin (amorphous resin, amorphous resin and crystalline resin, etc.) that is the raw material for the resin particles, and optionally PET or PBT, colorants, prepolymers (precursors of amorphous polyester resin A), wax, and other materials are dissolved or dispersed in an organic solvent to prepare the oil phase. Note that some of the materials may be added in the aggregation step described below. The method for preparing the oil phase is not particularly limited and can be appropriately selected depending on the purpose. For example, a method in which raw materials such as a resin are gradually added to an organic solvent while stirring, and dissolved or dispersed therein, can be mentioned. For dispersion, known dispersing machines such as a bead mill and a disk mill can be used. The raw materials used in the oil phase preparation step can be those described above in the section on <Resin Particles>. These may be used alone or in combination of two or more. At least one of the resins (amorphous resin, amorphous resin, and crystalline resin) is preferably a biomass-derived resin. The organic solvent is not particularly limited and can be appropriately selected depending on the purpose, but a volatile solvent with a boiling point of less than 100° C. is preferred because it makes it easier to remove the organic solvent later. Examples of such organic solvents include toluene, xylene, benzene, carbon tetrachloride, methylene chloride, 1,2-dichloroethane, 1,1,2-trichloroethane, trichloroethylene, chloroform, monochlorobenzene, dichloroethylidene, methyl acetate, ethyl acetate, butyl acetate, methyl ethyl ketone, methyl isobutyl ketone, methanol, ethanol, and isopropyl alcohol. These may be used alone or in combination of two or more. When the resin to be dissolved or dispersed in an organic solvent is a resin having a polyester skeleton, the organic solvent is preferably an ester solvent such as methyl acetate, ethyl acetate, or butyl acetate, or a ketone solvent such as methyl ethyl ketone or methyl isobutyl ketone, because of its high solubility. Among these, methyl acetate, ethyl acetate, or methyl ethyl ketone is preferred as the organic solvent, because of its high solvent removability.

[0089] The amount of organic solvent used is not particularly limited and can be selected appropriately depending on the purpose, but is preferably 40 to 300 parts by mass, more preferably 60 to 140 parts by mass, and even more preferably 80 to 120 parts by mass per 100 parts by mass of the raw material for the resin particles.

[0090] (Aqueous phase preparation process) In the aqueous phase preparation step, an aqueous phase (aqueous medium) is prepared. The aqueous medium is not particularly limited and can be appropriately selected from known aqueous media, and examples thereof include water, a water-miscible solvent, and a mixture thereof. From the viewpoint of granulation properties, the concentration of the water-miscible solvent is preferably equal to or lower than the saturation concentration of the ion-exchanged water used in the phase inversion emulsification step. The water-miscible solvent is not particularly limited and can be appropriately selected from known solvents, such as alcohol, dimethylformamide, tetrahydrofuran, cellosolves, lower ketones, and esters. Examples of alcohols include methanol, isopropanol, and ethylene glycol. Examples of lower ketones include acetone and methyl ethyl ketone. An example of the esters is ethyl acetate. These may be used alone or in combination of two or more.

[0091] (Phase inversion emulsification process) In the phase inversion emulsification step, the oil phase obtained in the oil phase preparation step is atomized. After neutralizing the oil phase, ion-exchanged water is added to the neutralized oil phase, and a fine particle dispersion is obtained by phase inversion emulsification, which inverts the water-in-oil dispersion into an oil-in-water dispersion. The phase inversion emulsification is carried out by stirring. This is done by uniformly mixing and dispersing using a conventional stirrer or dispersing device. The impeller is not particularly limited and can be appropriately selected depending on the viscosity of the solution. Examples include low-viscosity impellers such as paddles and propellers, medium-viscosity impellers such as anchors and maxblends, and high-viscosity impellers such as helical ribbons. The dispersing device is not particularly limited, and examples thereof include an ultrasonic disperser, a bead mill, a ball mill, a roll mill, a homomixer, an ultra mixer, a disperser mixer, a penetrating type high-pressure dispersing device, a collision type high-pressure dispersing device, a porous type high-pressure dispersing device, an ultra-high-pressure homogenizer, an ultrasonic homogenizer, etc. A conventional stirrer and a dispersing device may be used in combination.

[0092] Among these, paddle and anchor are preferred in that they can control the volume average particle size of the dispersion (oil droplets) within the above-mentioned preferred range.

[0093] The base used to neutralize the oil phase may be either a basic inorganic compound or a basic organic compound. Examples of basic inorganic compounds include sodium hydroxide, potassium hydroxide, lithium hydroxide, ammonia, sodium carbonate, sodium bicarbonate, potassium carbonate, potassium bicarbonate, and ammonia. Examples of basic organic compounds include N,N-dimethylethanolamine, N,N-diethylethanolamine, triethanolamine, tripropanolamine, tributanolamine, triethylamine, n-propylamine, n-butylamine, isopropylamine, monomethanolamine, morpholine, methoxypropylamine, pyridine, vinylpyridine, and isophoronediamine.

[0094] When using a stirring blade, the conditions such as the rotation speed, stirring time, and stirring temperature are not particularly limited and can be appropriately selected depending on the purpose. The rotation speed is not particularly limited, but is preferably 100 rpm to 1,000 rpm, and more preferably 200 rpm to 600 rpm. The stirring time and stirring temperature are not particularly limited and may be appropriately selected depending on the purpose.

[0095] A dispersant may also be used if necessary. The dispersant is not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include surfactants, poorly water-soluble inorganic compound dispersants, and polymeric protective colloids. These may be used alone or in combination of two or more. Among these, surfactants are preferred.

[0096] The surfactant is not particularly limited and can be appropriately selected depending on the purpose. For example, anionic surfactants, cationic surfactants, nonionic surfactants, amphoteric surfactants, etc. can be used.

[0097] The anionic surfactant is not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include alkylbenzene sulfonates, α-olefin sulfonates, phosphate esters, etc. Among these, those having a fluoroalkyl group are preferred.

[0098] (Desolvation process) In the solvent removal step, the organic solvent is removed from the resulting fine particle dispersion. To remove the organic solvent from the resulting fine particle dispersion, a method can be employed in which the temperature of the entire system is gradually increased while being stirred, and the organic solvent in the droplets is completely evaporated and removed.

[0099] Alternatively, the organic solvent in the droplets can be completely removed by spraying the obtained microparticle dispersion into a dry atmosphere while stirring. Furthermore, the organic solvent can be evaporated and removed by reducing the pressure while stirring the microparticle dispersion. Alternatively, the organic solvent can be evaporated and removed by blowing a gas onto the microparticle dispersion while stirring it. These means may be used alone or in combination.

[0100] The drying atmosphere in which the fine particle dispersion is sprayed is generally a gas such as air, nitrogen, carbon dioxide, or a heated combustion gas, particularly a gas stream heated to a temperature equal to or higher than the boiling point of the highest boiling point solvent used. The desired quality can be obtained by short-term processing using a spray dryer, belt dryer, rotary kiln, etc. By removing the organic solvent from the fine particle dispersion obtained by the above method, a fine particle dispersion liquid can be obtained.

[0101] (Agglutination process) In the aggregation step, the obtained fine particle dispersion is agitated to aggregate particles of a desired particle size, thereby obtaining aggregated particles.

[0102] Existing methods for flocculation, such as adding a flocculant or adjusting the pH, can be used. When adding a flocculant, it can be added directly, but it is preferable to use an aqueous solution of the flocculant, as this can prevent localized high concentrations. It is also preferable to add the flocculant gradually while monitoring the particle size of the fine particles. It is preferable to use Mg as the flocculant and perform the flocculation process under weak stirring. For example, methods such as using anchor blades with little vertical convection as stirring blades, stirring at a peripheral speed of 0.5 m / s to 3.0 m / s, or not installing baffles in the stirring tank can be adopted.

[0103] The temperature of the dispersion during aggregation is preferably near the glass transition temperature Tg of the resin used. If the liquid temperature of the microparticle dispersion is too low, aggregation does not proceed very well, resulting in poor efficiency. If the liquid temperature of the microparticle dispersion is too high, the aggregation rate increases, resulting in the generation of coarse particles and a deterioration in particle size distribution.

[0104] When the target particle size is reached, aggregation is stopped. Methods for stopping aggregation include adding a salt or a chelating agent with a low ionic valence, adjusting the pH, lowering the temperature of the dispersion, and adding a large amount of an aqueous medium to dilute the concentration. In the present invention, it is preferable to use Na as the aggregation stopper. By the above method, a dispersion of resin particles can be obtained.

[0105] In the aggregation step, a colorant, a crystalline resin, and a release agent may be added. In this case, the material is mixed with a dispersion in which the material is dispersed in an aqueous medium or the fine particle dispersion, and then aggregated to obtain aggregated particles in which the colorant, the crystalline resin, and the release agent are uniformly dispersed.

[0106] In this embodiment, it is preferable to use a metal salt of Na with a low ionic valence. By substituting Na for the metal used as the flocculant, flocculation can be stopped efficiently.

[0107] ((flocculant)) As the flocculant, a general flocculant can be used, and one flocculant may be used alone or two or more flocculants may be used in combination. However, in the present invention, it is preferable to use a divalent magnesium salt as the flocculant, as described above.

[0108] When a monovalent metal is used as a flocculant, the crosslinking effect is low. Furthermore, when using biomass resin, amorphous resin with many aromatic ring structures, and PET or PBT resin, there is a large difference in structure, and using a trivalent or higher metal salt with a fast crosslinking reaction rate results in a poor particle size distribution of the resin particles. Among divalent metals, Mg exhibited particularly good flocculation properties. Metals used as flocculants, etc., can worsen charging properties if they remain in the resin particles, so the amount of Mg in the resin particles is preferably 0.05 mass% or more and 0.30 mass% or less. Note that, in this specification, mass% and mass% are synonymous. The type and amount of metal in the resin particles can be adjusted by the type and amount of the flocculant and terminator, and the washing conditions in the washing process.

[0109] (fusion process) In the fusion step, the resulting aggregated particles are fused by heat treatment to reduce irregularities and to form spherical particles. Fusion can be achieved by heating the dispersion of aggregated particles while stirring. The temperature of the dispersion is preferably near a temperature above the glass transition temperature (Tg) of the resin used.

[0110] The method for forming the shell layer is not particularly limited and can be appropriately selected depending on the purpose. For example, the method for forming the shell layer includes a method in which spherical particles having a desired particle size are produced in a fusion step, an amorphous resin is added, and the aggregating step and the fusion step are repeated to form the shell layer.

[0111] (Washing and drying process) In the washing and drying step, only the resin particles are taken out from the resin particle dispersion obtained by the above method, washed, and dried.

[0112] The resin particle dispersion obtained by the above method contains secondary materials such as coagulated salts in addition to the resin particles, so washing is performed to extract only the resin particles from the dispersion. Methods for washing the resin particles include, but are not limited to, centrifugation, vacuum filtration, and filter press. While any of these methods produces a cake of resin particles, if the particles cannot be sufficiently washed in a single operation, the resulting cake may be dispersed again in an aqueous solvent to form a slurry, and the resin particles may be extracted by one of the above methods. Alternatively, if washing is performed by vacuum filtration or filter press, a method may be used in which the aqueous solvent is passed through the cake to wash away the secondary materials absorbed by the colored resin particles. The aqueous solvent used for this washing is water, or a mixed solvent of water and an alcohol such as methanol or ethanol. However, water is preferred from the standpoints of cost and environmental impact due to wastewater treatment. The washed resin particles contain a large amount of the aqueous medium, so the resin particles can be obtained by drying them to remove the aqueous medium.

[0113] Drying methods that can be used include dryers such as spray dryers, vacuum freeze dryers, reduced-pressure dryers, stationary shelf dryers, mobile shelf dryers, fluidized bed dryers, rotary dryers, and agitator dryers. The dried resin particles are preferably dried until the final moisture content is less than 1%. If the dried colored resin particles are in the form of soft agglomerates that cause inconvenience during use, they may be crushed using a device such as a jet mill, Henschel mixer, super mixer, coffee mill, Oster blender, or food processor to loosen the agglomerates.

[0114] (Annealing process) In the annealing process, when a crystalline resin is added, annealing after drying causes phase separation between the amorphous resin and the crystalline resin, improving fixability. Specifically, the toner is stored at a temperature near the glass transition temperature (Tg) for 10 hours or more.

[0115] (External addition process) To impart fluidity, chargeability, cleaning properties, etc. to the obtained resin particles, other components such as wax, external additives, colorants, charge control agents, and cleaning property improvers may be added and mixed. Specific mixing methods include a method in which an impact force is applied to the mixture using blades rotating at high speed, and a method in which the mixture is introduced into a high-speed air current, accelerated, and the particles or composite particles are caused to collide with an appropriate collision plate. Examples of equipment include an Ang Mill (manufactured by Hosokawa Micron Corporation), a modified I-type Mill (manufactured by Nippon Pneumatic Co., Ltd.) with reduced grinding air pressure, a Hybridization System (manufactured by Nara Machinery Works, Ltd.), a Cryptron System (manufactured by Kawasaki Heavy Industries, Ltd.), and an automatic mortar. [Example]

[0116] Examples of the present invention will be described below, but the present invention is not limited to the following examples. In the following description, "parts" and "%" represent "parts by mass" and "% by mass", respectively.

[0117] <Synthesis of amorphous polyester resin A-1> A four-neck flask equipped with a nitrogen inlet tube, a dehydration tube, a stirrer, and a thermocouple was charged with a mixture of 2-mol ethylene oxide adduct of bisphenol A, 3-mol propylene oxide adduct of bisphenol A, and biomass-derived propylene glycol in a molar ratio of 40 / 55 / 5, terephthalic acid / adipic acid in a molar ratio of 50 / 50, and a molar ratio of OH / COOH (hydroxyl group to carboxyl group) of 1.3. The mixture was reacted with titanium tetraisopropoxide (500 ppm relative to the resin components) at normal pressure and 230°C for 8 hours, and then further reacted at a reduced pressure of 10 to 15 mmHg for 4 hours. After that, trimellitic anhydride was added to the reaction vessel in an amount of 1 mol% relative to the total resin components, and the mixture was reacted at 18°C, normal pressure, and for 3 hours to obtain [Amorphous Polyester Resin A-1].

[0118] <Synthesis of amorphous polyester resin A-2> A four-neck flask equipped with a nitrogen inlet tube, a dehydration tube, a stirrer, and a thermocouple was charged with a mixture of 2-mol ethylene oxide adduct of bisphenol A, 3-mol propylene oxide adduct of bisphenol A, and biomass-derived propylene glycol in a molar ratio of 35 / 50 / 15, a mixture of terephthalic acid, adipic acid, and biomass-derived succinic acid in a molar ratio of 40 / 45 / 15, and a molar ratio of hydroxyl groups to carboxyl groups (OH / COOH) of 1.3. The mixture was reacted with titanium tetraisopropoxide (500 ppm relative to the resin components) at atmospheric pressure and 230°C for 8 hours, and then further reacted at a reduced pressure of 10 to 15 mmHg for 4 hours. After this, trimellitic anhydride was added to the reaction vessel in an amount of 1 mol% relative to the total resin components, and the mixture was reacted at 18°C, atmospheric pressure, and for 3 hours to obtain [Amorphous Polyester Resin A-2].

[0119] <Synthesis of amorphous polyester resin A-3> In a four-neck flask equipped with a nitrogen inlet tube, a dehydration tube, a stirrer, and a thermocouple, a mixture of bisphenol A ethylene oxide 2 mole adduct / bisphenol A propylene oxide 3 mole adduct / flake-form recycled PET (ethylene glycol unit unit) / biomass-derived propylene glycol in a molar ratio of 35 / 45 / 5 / 15, and a mixture of flake-form recycled PET (terephthalic acid unit unit) / terephthalic acid / adipic acid / biomass-derived amber was added. The mixture was charged with the acid in a molar ratio of 5 / 40 / 40 / 15, and the molar ratio of hydroxyl groups to carboxyl groups, OH / COOH, was 1.3. This was reacted with titanium tetraisopropoxide (500 ppm relative to the resin components) at normal pressure and 230°C for 8 hours, and then reacted for a further 4 hours at a reduced pressure of 10 mmHg to 15 mmHg. After that, trimellitic anhydride was added to the reaction vessel in an amount of 1 mol% relative to the total resin components, and this was reacted at 18°C, normal pressure, for 3 hours to obtain [Amorphous Polyester Resin A-3].

[0120] <Synthesis of amorphous polyester resin A-4> In a four-neck flask equipped with a nitrogen inlet tube, a dehydration tube, a stirrer, and a thermocouple, a mixture of 2 moles of bisphenol A ethylene oxide adduct, 3 moles of bisphenol A propylene oxide adduct, flake-form recycled PET (ethylene glycol unit unit), and biomass-derived propylene glycol in a molar ratio of 25 / 30 / 30 / 15, and a mixture of 2 moles of flake-form recycled PET (terephthalic acid unit unit), terephthalic acid, adipic acid, and biomass-derived amber was added. The mixture was charged with the acid in a molar ratio of 30 / 25 / 30 / 15, and the molar ratio of hydroxyl groups to carboxyl groups, OH / COOH, was 1.3. This was reacted with titanium tetraisopropoxide (500 ppm relative to the resin components) at normal pressure and 230°C for 8 hours, and then reacted for a further 4 hours at a reduced pressure of 10 to 15 mmHg. After that, trimellitic anhydride was added to the reaction vessel in an amount of 1 mol% relative to the total resin components, and this was reacted at 18°C, normal pressure, for 3 hours to obtain [Amorphous Polyester Resin A-4].

[0121] <Synthesis of amorphous polyester resin A-5> In a four-neck flask equipped with a nitrogen inlet tube, a dehydration tube, a stirrer, and a thermocouple, a mixture of 2-mol ethylene oxide adduct of bisphenol A, 3-mol propylene oxide adduct of bisphenol A, flaked recycled PET (ethylene glycol unit unit), and biomass-derived propylene glycol in a molar ratio of 15 / 20 / 50 / 15, and a mixture of 1-mol terephthalic acid, adipic acid, and biomass-derived amber in a molar ratio of 15 / 20 / 50 / 15, was added. The mixture was charged with the acid in a molar ratio of 50 / 15 / 20 / 15, and the molar ratio of hydroxyl groups to carboxyl groups, OH / COOH, was 1.3. This was reacted with titanium tetraisopropoxide (500 ppm relative to the resin components) at normal pressure and 230°C for 8 hours, and then reacted for a further 4 hours at a reduced pressure of 10 to 15 mmHg. After that, trimellitic anhydride was added to the reaction vessel in an amount of 1 mol% relative to the total resin components, and this was reacted at 18°C, normal pressure, for 3 hours to obtain [Amorphous Polyester Resin A-5].

[0122] <Synthesis of crystalline polyester resin C-1> Plant-derived sebacic acid and 1,6-hexanediol were placed in a 5 L four-neck flask equipped with a nitrogen inlet tube, a dehydration tube, a stirrer, and a thermocouple so that the molar ratio of hydroxyl groups to carboxyl groups, OH / COOH, was 0.9. The mixture was reacted with titanium tetraisopropoxide (500 ppm relative to the resin component) at 180°C for 10 hours, then heated to 200°C and reacted for 3 hours, and then further reacted at a pressure of 8.3 kPa for 2 hours to obtain [Crystalline Polyester Resin C-1].

[0123] <Preparation of Masterbatch (MB-1)> 1,200 parts of water, 500 parts of carbon black (Printex 35, manufactured by Degussa) [DBP oil absorption = 42 mL / 100 mg, pH = 9.5], and 500 parts of [amorphous polyester resin A-1] were added and mixed in a Henschel mixer (manufactured by Nippon Coke and Engineering Co., Ltd.). The resulting mixture was kneaded using two rolls at 150°C for 30 minutes, then rolled and cooled, and pulverized in a pulverizer to obtain [masterbatch MB-1].

[0124] <Preparation of WAX Dispersion> In a container equipped with a stirrer and a thermometer, 42 parts of carnauba wax (manufactured by Noda Ceramics Co., RN-5, plant-based wax, melting point 82°C) as a mold release agent and 420 parts of ethyl acetate were charged. The temperature was raised to 80°C with stirring and held at 80°C for 5 hours, then cooled to 30°C over 1 hour. Using a bead mill (Ultraviscomill, manufactured by Imex Co., Ltd.), dispersion was carried out under the conditions of a liquid feeding rate of 1 kg / hr, a disk peripheral speed of 6 m / sec, 80% by volume filling of zirconia beads with a diameter of 0.5 mm, and 3 passes to obtain [WAX Dispersion W-1]. The average particle size was 400 nm and the solid content concentration was 4%.

[0125] <Preparation of Crystalline Polyester Dispersion> In a container equipped with a stirrer and a thermometer, 308 parts of [Crystalline Polyester Resin C-1] and 1900 parts of ethyl acetate were charged. Next, while stirring, the temperature was raised to 80°C and held for 5 hours, then cooled to 30°C over 1 hour. Further, using the Ultraviscomill of the bead mill (manufactured by Imex Co., Ltd.), zirconia beads with a diameter of 0.5 mm were filled at 80% by volume and dispersed under the conditions of 3 passes to obtain [Crystalline Polyester Dispersion]. The volume average particle size was 450 nm and the solid content concentration was 11%.

[0126] <Production Example of Sulfonate Group-containing Resin S1> A 5 L four-neck flask equipped with a nitrogen inlet tube, a dehydration tube, a stirrer, and a thermocouple was charged with 35 parts of an ethylene oxide 2 mol adduct of bisphenol A, 80 parts of a propylene oxide 2 mol adduct of bisphenol A, 30 parts of recycled PET flakes (containing ethylene glycol units), 10 parts of biomass-derived glycerol, 100 parts of recycled PET flakes (containing terephthalic acid units), 22 parts of biomass-derived succinic acid, and 12.3 parts of sodium 5-sulfoisophthalate. Tetrabutyl orthotitanate was added as a condensation catalyst in an amount of 1000 ppm relative to the total amount of monomers. The mixture was heated to 230°C under a nitrogen stream over 2 hours, and the reaction was carried out for 5 hours while the generated water was distilled off. After that, the mixture was reacted for 4 hours under a reduced pressure of 5 mmHg to 15 mmHg, and cooled to 180°C. After that, 0.21 parts of trimellitic anhydride and 200 ppm of tetrabutyl orthotitanate relative to the total amount of monomers were added, and the mixture was reacted at 180°C under normal pressure for 1 hour, and then further reacted for 3 hours under a reduced pressure of 5 mmHg to 20 mmHg to obtain a sulfonic acid group-containing resin S1.

[0127] Example 1 <Preparation of oil phase 1> 1589 parts of [WAX Dispersion], 1628 parts of [Amorphous Polyester Resin A-1], 1437 parts of [Crystalline Polyester Dispersion], 637 parts of ethyl acetate, and 557 parts of [Masterbatch] were added and stirred to dissolve and disperse. 45 parts of ethyl acetate and 242 parts of 10% aqueous sodium hydroxide solution were added while stirring to obtain [Oil Phase 1]. The solids content of the obtained oil phase was 50%.

[0128] <Preparation of aqueous phase 1> 9283 parts of ion-exchanged water, 839 parts of ethyl acetate, and 520 parts of a surfactant (sodium dodecyl sulfate, solid content 30%) were mixed and stirred to obtain a milky white [aqueous phase 1].

[0129] <Preparation of Core Emulsion 1> [Water Phase 1] was gradually added to [Oil Phase 1] to perform phase inversion emulsification. After that, the solvent was removed to obtain [Core Emulsion 1]. The solid content of the obtained core emulsion was 20%.

[0130] <Aggregation and shell formation process> 15,000 parts of [Core Emulsion 1] and 15,000 parts of ion-exchanged water were placed in a container (without baffles and anchor blades) and stirred for 5 minutes. Next, 1,575 parts of a 10% aqueous magnesium sulfate solution were added dropwise and stirred for another 5 minutes, after which the temperature was raised to 44°C. After that, the particle size reached 5.0 μm.

[0131] <Stopping and fusing process> 6696 parts of a 10% aqueous sodium sulfate solution was added, and the temperature was raised to 70°C. When the desired circularity of 0.960 to 0.970 was reached, the mixture was cooled to obtain [Dispersion Slurry 1].

[0132] <Annealing process, cleaning, drying process> [Dispersion Slurry 1] was stored at 45°C for 10 hours, filtered under reduced pressure, and washed and dried as follows. (1) 100 parts of ion-exchanged water was added to the filter cake, and the mixture was mixed with a TK homomixer (at 12,000 rpm for 10 minutes) and then filtered. (2): 900 parts of ion-exchanged water was added to the filter cake of (1), and the mixture was mixed with ultrasonic vibrations in a TK homomixer (at 12,000 rpm for 30 minutes), followed by vacuum filtration. This process was repeated until the electrical conductivity of the reslurry liquid reached 10 μC / cm or less, and then filtered to obtain [Filter Cake 1]. The filter cake was dried in a circulating air dryer at 45°C for 48 hours and sieved through a 75 μm mesh to obtain [Toner Base Particles 1].

[0133] <External additive processing process> 100 parts of [toner base particles 1] and 2.0 parts of hydrophobic silica (HDK-2000, manufactured by Clariant KK) were mixed in a Henschel mixer, and the mixture was passed through a 500 mesh sieve to obtain [toner 1].

[0134] Example 2 Toner 2 was obtained in the same manner as in Example 1, except that the amount of 10% magnesium sulfate was changed to 734 parts and the amount of 10% sodium sulfate was changed to 6822 parts.

[0135] Example 3 Toner 3 was obtained in the same manner as in Example 1, except that the amount of 10% magnesium sulfate was changed to 324 parts and the amount of 10% sodium sulfate was changed to 6883 parts.

[0136] Example 4 Toner 4 was obtained in the same manner as in Example 1, except that the amount of 10% sodium sulfate in Example 1 was changed to 1,180 parts and the amount of 10% sodium sulfate was changed to 6,755 parts.

[0137] Example 5 Toner 4 was obtained in the same manner as in Example 1, except that the amount of 10% magnesium sulfate was changed to 734 parts and the amount of 10% sodium sulfate was changed to 3941 parts.

[0138] Example 6 Toner 6 was obtained in the same manner as in Example 1, except that the amount of 10% magnesium sulfate was changed to 324 parts and the amount of 10% sodium sulfate was changed to 1988 parts.

[0139] Example 7 Toner 7 was obtained in the same manner as in Example 1, except that the amount of 10% magnesium sulfate was changed to 1,180 parts and the amount of 10% sodium sulfate was changed to 5,704 parts.

[0140] Example 8 [Toner 8] was obtained in the same manner as in Example 1, except that the [Amorphous Polyester Resin A-1] in Example 1 was changed to [Amorphous Polyester Resin A-2], 734 parts of 10% magnesium sulfate, and 3941 parts of 10% sodium sulfate.

[0141] Example 9 [Toner 9] was obtained in the same manner as in Example 1, except that the [Amorphous Polyester Resin A-1] in Example 1 was changed to [Amorphous Polyester Resin A-3], 734 parts of 10% magnesium sulfate, and 3941 parts of 10% sodium sulfate.

[0142] Example 10 [Toner 10] was obtained in the same manner as in Example 1, except that the [Amorphous Polyester Resin A-1] in Example 1 was changed to [Amorphous Polyester Resin A-4], 734 parts of 10% magnesium sulfate, and 3941 parts of 10% sodium sulfate.

[0143] Example 11 [Toner 11] was obtained in the same manner as in Example 1, except that the [Amorphous Polyester Resin A-1] in Example 1 was changed to [Amorphous Polyester Resin A-5], 734 parts of 10% magnesium sulfate, and 3941 parts of 10% sodium sulfate.

[0144] Example 12 <Preparation of oil phase 2> 1843 parts of [WAX Dispersion], 1412 parts of [Amorphous Polyester Resin A-1], 1667 parts of [Crystalline Polyester Dispersion], 637 parts of ethyl acetate, and 646 parts of [Masterbatch] were added and stirred to dissolve and disperse. 45 parts of ethyl acetate and 242 parts of 10% aqueous sodium hydroxide solution were added while stirring to obtain [Oil Phase 1]. The solids content of the obtained oil phase was 50%.

[0145] <Preparation of Shell Emulsion 1> <Preparation of shell resin solution 1> 4,200 parts of [sulfonate group-containing resin S1] and 4,200 parts of methyl ethyl ketone were placed in a container and mixed at 5,000 rpm for 60 minutes using a TK Homomixer (manufactured by Primix Corporation) to obtain [shell resin solution 1]. The solid content of the resulting oil phase was 50%. <Preparation of shell aqueous phase 1> 9828 parts of ion-exchanged water and 2772 parts of methyl ethyl ketone were mixed and stirred to obtain [shell aqueous phase 1]. <Preparation of Shell Emulsion 1> While stirring 8,400 parts of [Shell Resin Solution 1] at 8,000 rpm with a TK Homomixer, 124 parts of 28% aqueous ammonia was added and mixed for 10 minutes, after which 12,600 parts of [Shell Aqueous Phase 1] was gradually added to carry out phase inversion emulsification. The solvent was then removed to obtain [Shell Emulsion 1].

[0146] [Toner 12] was obtained in the same manner as in Example 1, except that Oil Phase 1 in Example 1 was changed to Oil Phase 2, 1411 parts of 10% magnesium sulfate, and 6605 parts of 10% sodium sulfate were changed, and 3968 parts of [Shell Emulsion 1] was added.

[0147] (Comparative Example 1) Toner 13 was obtained in the same manner as in Example 1, except that the amount of 10% magnesium sulfate was changed to 2025 parts and the amount of 10% sodium sulfate was changed to 5208 parts.

[0148] Table 1 shows the formulations of the above examples.

[0149] <Evaluation> (High temperature fixability) Using the fixing unit of a color multifunction printer (imagio MP C5503, manufactured by Ricoh Co., Ltd.), a 0.6 mg / cm 2 The temperature at which hot offset occurred was measured and evaluated according to the following criteria. [Evaluation criteria] ◎: 190℃ or higher ○: 180℃ or higher but lower than 190℃ △: 170℃ or more and less than 180℃ ×: Less than 170℃ ◎, ◯ and △ ratings are passing.

[0150] (low temperature fixability) Using the fixing unit of a color multifunction printer (imagio MP C5503, manufactured by Ricoh Co., Ltd.), a 0.6 mg / cm 2 The temperature at which cold offset occurred was measured and evaluated according to the following criteria. [Evaluation criteria] ◎: Less than 120℃ ○: 120℃ or higher but lower than 125℃ △: 125℃ or higher but lower than 130℃ ×: 130℃ or higher ◎, ◯ and △ ratings are passing.

[0151] (Charging property) Six grams of two-component developer was weighed and placed in a sealed metal cylinder. The developer was stirred at 280 rpm, and the charge amount was measured using the blow-off method. The stirring time was 60 seconds (TA60) and 600 seconds (TA600). The carrier used was TEFV200 / 300 (manufactured by Powder Tech Co., Ltd.). ◎: 36 or more ○: 33 or more and less than 36 △: 30 or more and less than 33 ×: Less than 30 ◎, ◯ and △ ratings are passing.

[0152] Table 1 shows the evaluation results of the toners of the examples and comparative examples. Table 1 also shows the radioactive carbon isotopes of the toners. 14 The C concentration, Dv, Dv / Dn and circularity are also shown.

[0153] [Table 1]

[0154] The embodiments of the present invention are as follows, for example. <1> Resin particles containing Mg and Na as metal elements, Resin particles, characterized in that the Mg content (mass%) in the resin particles measured by fluorescent X-ray analysis is less than the Na content (mass%) in the resin particles measured by fluorescent X-ray analysis. <2> The Mg content is 0.05 mass% or more and 0.30 mass% or less with respect to the entire resin particles. <1> The resin particles according to claim 1. <3> The Na content is 0.10 mass% or more and 0.40 mass% or less with respect to the entire resin particles. <1> or <2> The resin particles according to claim 1. <4> Radiocarbon isotopes of the resin particles 14 C concentration is 10.8 pMC or more, <1> ~ <3> 1. The resin particles according to any one of the above. <5> The resin particles contain polyethylene terephthalate or polybutylene terephthalate. <1> ~ <4> 1. The resin particles according to any one of the above. <6> The resin particles contain the polyethylene terephthalate or polybutylene terephthalate and a biomass-derived resin, and the content of the polyethylene terephthalate or polybutylene terephthalate in the resin particles is greater than the content of the biomass-derived resin. <1> ~ <5> 1. The resin particles according to any one of the above. <7> The resin particles form a core-shell structure, and the shell layer contains at least a sulfonate group. <1> ~ <6> 1. The resin particles according to any one of the above. <8> <1> ~ <7> A method for producing the resin particles according to any one of the above items, The method includes a step of preparing a solution by dissolving or dispersing a resin in an organic solvent, a step of adding water to the solution to invert the phase from a water-in-oil dispersion to an oil-in-water dispersion, and an aggregating step of aggregating fine particles in the oil-in-water dispersion using an aggregating agent and terminating the aggregating at a predetermined time point using a terminator, The method for producing the agglomerate is characterized in that the agglomerant is a divalent metal element, Mg. <9> The terminator is a monovalent metal element, Na. <8> 1. A method for producing resin particles according to claim 1. <10> <1> ~ <7> 1. A toner containing the resin particles according to any one of 1 to 8. [Prior art documents] [Patent documents]

[0155] [Patent Document 1] Japanese Patent Publication No. 2022-181043 [Patent Document 2] Patent No. 4625386 [Patent Document 3] Patent No. 7069809 [Patent Document 4] Japanese Patent Application Laid-Open No. 2010-145508

Claims

1. Resin particles containing Mg and Na as metal elements, Resin particles, characterized in that the Mg content (mass %) in the resin particles measured by fluorescent X-ray analysis is less than the Na content (mass %) in the resin particles measured by fluorescent X-ray analysis.

2. The resin particles according to claim 1, wherein the Mg content is 0.05 mass% or more and 0.30 mass% or less with respect to the entire resin particles.

3. The resin particles according to claim 1, wherein the Na content is 0.10 mass % or more and 0.40 mass % or less with respect to the entire resin particles.

4. Radioactive carbon isotopes of the resin particles １４ The resin particles according to claim 1, wherein the C concentration is 10.8 pMC or more.

5. The resin particles according to claim 1 , wherein the resin particles contain polyethylene terephthalate or polybutylene terephthalate.

6. The resin particles described in claim 1, characterized in that the resin particles contain the polyethylene terephthalate or polybutylene terephthalate and a biomass-derived resin, and the polyethylene terephthalate or polybutylene terephthalate content of the resin particles is greater than the biomass-derived resin content.

7. 2. The resin particles according to claim 1, wherein the resin particles form a core-shell structure, and the shell layer contains at least a sulfonate group.

8. A method for producing the resin particles according to claim 1, comprising: The method includes a step of preparing a solution by dissolving or dispersing a resin in an organic solvent, a step of adding water to the solution to invert the phase from a water-in-oil dispersion to an oil-in-water dispersion, and an aggregating step of aggregating fine particles in the oil-in-water dispersion using an aggregating agent and terminating the aggregating at a predetermined time point using a terminator, The method for producing the present invention is characterized in that the flocculant is a divalent metal element, Mg.

9. 9. The method according to claim 8, wherein the terminator is a monovalent metal element, Na.

10. A toner containing the resin particles according to claim 1.

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