Toner, toner cartridge, and image forming apparatus

Abstract

To provide a toner that has improved low temperature fixability, is excellent in low temperature fixability even under a high temperature and high humidity environment, and can maintain a sufficient electrification amount; a toner cartridge that stores the toner; and an image forming apparatus.SOLUTION: A toner of an embodiment has toner base particles. The toner base particles contain a crystalline polyester resin component and an amorphous polyester resin component. Of a plurality of amorphous polyester resins in the amorphous polyester resin component, a glass-transition temperature of an amorphous polyester resin A contained in the largest amount is 52°C or lower; a melting temperature of at least one type of amorphous polyester resin B other than the amorphous polyester resin A is 100°C or higher; a ratio of the amorphous polyester resin A is 80 mass% or more, and a ratio of the amorphous polyester resin B is 20 mass% or less. A ratio of the crystalline polyester resin component in the toner base particles is 10 mass% or less.SELECTED DRAWING: None

Description

[Technical field]

[0001] An embodiment of the present invention relates to a toner, a toner cartridge, and an image forming apparatus. [Background technology]

[0002] Toners containing crystalline polyester resins are known (for example, Patent Document 1). Crystalline polyester resins have a low glass transition temperature, and are therefore used in low-temperature fixing toners. Low-temperature fixing toners can be suitably applied to image forming apparatuses equipped with a heating fixing device.

[0003] For low-temperature fixing toners, further improvement in low-temperature fixing property is required from the viewpoint of power saving and the like. However, when a low-temperature fixing toner containing a crystalline polyester resin is left in a high-temperature and high-humidity environment, the glass transition temperature of the crystalline polyester resin in the toner increases rapidly, and therefore the low-temperature fixing property in the high-temperature and high-humidity environment decreases. In addition, since the crystalline polyester resin has high hygroscopicity, in a low-temperature fixing toner containing the crystalline polyester resin, the charge amount of the toner is likely to decrease in a high-temperature and high-humidity environment. For the above reasons, it is difficult for conventional low-temperature fixing toners to maintain excellent low-temperature fixing properties and chargeability in a high-temperature and high-humidity environment. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 3693327 Summary of the Invention [Problem to be solved by the invention]

[0005] The problem to be solved by the present invention is to provide a toner that has excellent low-temperature fixing properties at room temperature, and also has excellent low-temperature fixing properties and chargeability in a hot and humid environment; and toner cartridge and image forming apparatus containing said toner. [Means for solving the problem]

[0006] The toner of the embodiment has toner base particles. The toner base particles contain a crystalline polyester resin component and a non-crystalline polyester resin component. The non-crystalline polyester resin component contains at least two or more types of non-crystalline polyester resins. Of the multiple amorphous polyester resins, amorphous polyester resin A, which is the resin with the greatest content, has a glass transition temperature of 52° C. or lower. Among the plurality of amorphous polyester resins, at least one amorphous polyester resin B other than the amorphous polyester resin A has a melting temperature of 100° C. or higher. The proportion of the amorphous polyester resin A is 80% by mass or more relative to 100% by mass of the amorphous polyester resin component. The proportion of the amorphous polyester resin B is 20% by mass or less with respect to 100% by mass of the amorphous polyester resin component. The proportion of the crystalline polyester resin component is 10% by mass or less with respect to 100% by mass of the toner base particles. [Brief description of the drawings]

[0007] [Figure 1] 1 is a diagram illustrating an example of a schematic structure of an image forming apparatus according to an embodiment; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] First, the toner according to the embodiment of the first aspect will be described. The toner of the embodiment includes toner base particles. The toner of the embodiment may further include an external additive attached to the surface of the toner base particles.

[0009] The toner base particles will now be described. The toner base particles contain a crystalline polyester resin component and a non-crystalline polyester resin component. The toner base particles may further contain a colorant and a release agent in addition to the crystalline polyester resin component and the non-crystalline polyester resin component. The toner base particles may further contain other components in addition to the crystalline polyester resin component, the non-crystalline polyester resin component, the colorant, and the release agent, as long as the effects disclosed in the embodiment are obtained.

[0010] In the embodiment, a polyester resin having a ratio of softening temperature to melting temperature (softening temperature / melting temperature) of less than 0.8 or more than 1.2 is defined as a "non-crystalline polyester resin." A polyester resin having a ratio of softening temperature to melting temperature (softening temperature / melting temperature) of 0.8 to 1.2 is defined as a "crystalline polyester resin."

[0011] The non-crystalline polyester resin component will now be described. The amorphous polyester resin component contains at least two or more kinds of amorphous polyester resins. Among the amorphous polyester resins, the amorphous polyester resin with the largest content is amorphous polyester resin A. The glass transition temperature of amorphous polyester resin A is 52°C or lower. Among the plurality of amorphous polyester resins, a resin having a melting temperature of 100° C. or higher is amorphous polyester resin B. Amorphous polyester resin B is at least one resin other than amorphous polyester resin A.

[0012] The non-crystalline polyester resin A will be described. The glass transition temperature of the amorphous polyester resin A is 52° C. or less. Therefore, the toner of the embodiment has excellent low-temperature fixing properties, and also has excellent low-temperature fixing properties in a high-temperature and high-humidity environment. In the toner of the embodiment, the glass transition temperature of the amorphous polyester resin A is set to 52° C. or less, so that the toner has excellent offset resistance at low temperatures. As a result, the low-temperature fixing properties can be further improved compared to conventional low-temperature fixing toners. The glass transition temperature of the amorphous polyester resin A is preferably 42 to 52° C., more preferably 45 to 52° C., and even more preferably 47 to 50° C. When the glass transition temperature of the amorphous polyester resin A is equal to or higher than the lower limit of the above-mentioned range, the toner is less likely to adhere to the roller during fixing, and therefore the toner has excellent offset resistance. The glass transition temperature of the non-crystalline polyester resin A can be measured, for example, by a differential scanning calorimeter (DSC).

[0013] The mass average molecular weight of the amorphous polyester resin A is 5×10 3 ~9×10 3 is preferred, 5×10 3 ~8×10 3 is more preferable, and 6×10 3 ~8×10 3 When the mass average molecular weight of the amorphous polyester resin A is within the above range, the glass transition temperature of the amorphous polyester resin A tends to be 52° C. or lower. In addition, when the mass average molecular weight of the non-crystalline polyester resin A is equal to or greater than the lower limit, the viscosity of the toner during fixing is increased, and the low-temperature fixing property is further improved. When the mass average molecular weight of the non-crystalline polyester resin A is equal to or less than the upper limit, the viscosity of the toner during fixing is reduced. Therefore, the toner is less likely to adhere to the roller during fixing, and the offset resistance is excellent. The mass average molecular weight of the non-crystalline polyester resin A is a value calculated as polyethylene glycol by gel permeation chromatography.

[0014] The non-crystalline polyester resin A may be, for example, a condensation polymer of a divalent or higher carboxylic acid and a divalent or higher alcohol. Examples of divalent or higher carboxylic acids include divalent or higher carboxylic acids, acid anhydrides of divalent or higher carboxylic acids, esters of divalent or higher carboxylic acids, etc. Examples of esters of divalent or higher carboxylic acids include lower alkyl (carbon number 1 to 12) esters of divalent or higher carboxylic acids.

[0015] Examples of divalent carboxylic acids include maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, phthalic acid, isophthalic acid, terephthalic acid, cyclohexanedicarboxylic acid, succinic acid, adipic acid, sebacic acid, azelaic acid, malonic acid, and succinic acid substituted with an alkyl group or an alkenyl group, but the divalent carboxylic acid is not limited to these examples. The succinic acid substituted with an alkyl or alkenyl group includes succinic acid substituted with an alkyl or alkenyl group having 2 to 20 carbon atoms. Examples of the succinic acid include n-dodecenylsuccinic acid and n-dodecylsuccinic acid. In addition, an acid anhydride of the dicarboxylic acid or an ester of the dicarboxylic acid may be used. As the divalent carboxylic acid, maleic acid, fumaric acid, terephthalic acid, and succinic acid substituted with an alkenyl group having 2 to 20 carbon atoms are preferred. The divalent carboxylic acids may be used alone or in combination of two or more.

[0016] Examples of trivalent or higher carboxylic acids include 1,2,4-benzenetricarboxylic acid, 2,5,7-naphthalenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, 1,2,4-butanetricarboxylic acid, 1,2,5-hexanetricarboxylic acid, 1,3-dicarboxyl-2-methyl-2-methylenecarboxypropane, 1,2,4-cyclohexanetricarboxylic acid, tetra(methylenecarboxyl)methane, 1,2,7,8-octanetetracarboxylic acid, pyromellitic acid, empol trimer acid, acid anhydrides thereof, or esters thereof. However, the trivalent or higher carboxylic acid is not limited to these examples. As the trivalent or higher carboxylic acid, 1,2,4-benzenetricarboxylic acid (trimellitic acid), its acid anhydride or its lower alkyl (having 1 to 12 carbon atoms) ester is preferred. The trivalent or higher carboxylic acids may be used either individually or in combination of two or more.

[0017] Examples of dihydric alcohols include ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, neopentyl glycol, 1,4-butenediol, 1,5-pentanediol, 1,6-hexanediol, 1,4-cyclohexanedimethanol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, bisphenol A, hydrogenated bisphenol A, and alkylene oxide adducts of bisphenol A. However, the dihydric alcohol is not limited to these examples. Examples of the alkylene oxide adduct of bisphenol A include compounds in which an average of 1 to 10 moles of alkylene oxide having 2 to 3 carbon atoms is added to bisphenol A. Examples of the alkylene oxide adduct of bisphenol A include polyoxypropylene (2.2)-2,2-bis(4-hydroxyphenyl)propane, polyoxypropylene (3.3)-2,2-bis(4-hydroxyphenyl)propane, polyoxyethylene (2.0)-2,2-bis(4-hydroxyphenyl)propane, polyoxypropylene (2.0)-polyoxyethylene (2.0)-2,2-bis(4-hydroxyphenyl)propane, and polyoxypropylene (6)-2,2-bis(4-hydroxyphenyl)propane. The dihydric alcohol is preferably an alkylene oxide adduct of bisphenol A. The dihydric alcohol may be used alone or in combination of two or more kinds.

[0018] Examples of trihydric or higher alcohols include sorbitol, 1,2,3,6-hexanetetrol, 1,4-sorbitan, pentaerythritol, dipentaerythritol, tripentaerythritol, 1,2,4-butanetriol, 1,2,5-pentanetriol, glycerol, 2-methylpropanetriol, 2-methyl-1,2,4-butanetriol, trimethylolethane, trimethylolpropane, 1,3,5-trihydroxymethylbenzene, etc. However, the trihydric or higher alcohol is not limited to these examples. As the trihydric or higher alcohol, sorbitol, 1,4-sorbitan, pentaerythritol, glycerol, and trimethylolpropane are preferred. The trihydric or higher alcohol may be used alone or in combination of two or more kinds.

[0019] Among these divalent or higher carboxylic acids and divalent or higher alcohols, the carboxylic acids and alcohols are selected so that the glass transition temperature of the non-crystalline polyester resin A becomes 52° C. or lower. The melting temperature and mass average molecular weight of the non-crystalline polyester resin A can be adjusted by, for example, selecting the type and composition of the divalent or higher carboxylic acid and divalent or higher alcohol, and changing the polymerization time.

[0020] When polycondensing dihydric or higher alcohols and dihydric or higher carboxylic acids, a commonly used catalyst may be used to promote the reaction. Examples of the catalyst include dibutyltin oxide, titanium compounds, dialkoxytin(II), tin(II) oxide, fatty acid tin(II), tin(II) dioctanoate, and tin(II) distearate.

[0021] The amorphous polyester resin B will now be described. The melting temperature of the amorphous polyester resin B is 100° C. or higher. Therefore, the toner of the embodiment is less likely to adhere to the roller during fixing, and has excellent offset resistance at high temperatures. The toner also has excellent storage stability. The melting temperature of the amorphous polyester resin B is preferably 100 to 160° C., more preferably 120 to 160° C., even more preferably 120 to 150° C., and particularly preferably 130 to 150° C. When the melting temperature of the amorphous polyester resin B is equal to or lower than the upper limit of the aforementioned numerical range, the toner has even more excellent low-temperature fixing property. The melting temperature of the non-crystalline polyester resin B can be measured, for example, by a constant test force extrusion type capillary rheometer (flow tester).

[0022] The mass average molecular weight of the amorphous polyester resin B is 1×10 4 ~9×10 4 is preferred, 2×10 4 ~7×10 4 is more preferable, and 2 × 10 4 ~6×10 4 When the mass average molecular weight of the amorphous polyester resin B is within the above range, the melting temperature of the amorphous polyester resin B tends to be 100° C. or higher. In addition, when the mass average molecular weight of the non-crystalline polyester resin B is equal to or higher than the lower limit, the viscosity of the toner during fixing is increased, and low-temperature fixing properties are further improved. When the mass average molecular weight of the non-crystalline polyester resin B is equal to or lower than the upper limit, the viscosity of the toner during fixing is decreased, and offset is less likely to occur. The mass average molecular weight of the non-crystalline polyester resin B is a value calculated as polyethylene glycol by gel permeation chromatography.

[0023] Examples of the non-crystalline polyester resin B include a condensation polymer of a divalent or higher carboxylic acid and a divalent or higher alcohol. Examples of the divalent or higher carboxylic acid and the divalent or higher alcohol include those similar to those explained for the non-crystalline polyester resin A. From these divalent or higher carboxylic acids and divalent or higher alcohols, carboxylic acids and alcohols are selected so that the melting temperature is 100° C. or higher. The melting temperature and mass average molecular weight of the non-crystalline polyester resin B can be adjusted by, for example, selecting the type and composition of the divalent or higher carboxylic acid and divalent or higher alcohol, and changing the polymerization time.

[0024] The amorphous polyester resin component may further contain an amorphous polyester resin other than the amorphous polyester resin A and the amorphous polyester resin B. Other examples of the amorphous polyester resin include amorphous polyester resins having a glass transition temperature of more than 52°C and amorphous polyester resins having a melting temperature of less than 100°C. The other amorphous polyester resins may be contained in the amorphous polyester resin component either alone or in combination of two or more.

[0025] The proportion of the amorphous polyester resin A is 80% by mass or more relative to 100% by mass of the amorphous polyester resin component, so that the toner of the embodiment has excellent low-temperature fixing property at room temperature. In the first embodiment, the proportion of the amorphous polyester resin A is preferably 80 to 90% by mass, and more preferably 80 to 85% by mass, relative to 100% by mass of the amorphous polyester resin component. When the proportion of the amorphous polyester resin A is equal to or less than the upper limit of the above numerical range, the toner has excellent storage stability.

[0026] The proportion of the amorphous polyester resin B is 20% by mass or less relative to 100% by mass of the amorphous polyester resin component, so that the toner of the embodiment has excellent low-temperature fixing property at room temperature. In the first embodiment, the proportion of the amorphous polyester resin B is preferably 10 to 20% by mass, and more preferably 15 to 20% by mass, relative to 100% by mass of the amorphous polyester resin component. When the proportion of the amorphous polyester resin B is equal to or more than the lower limit of the above numerical range, the toner has excellent storage stability.

[0027] In the toner of the embodiment, the ratio of the amorphous polyester resin A is 80% by mass or more and the ratio of the amorphous polyester resin B is 20% by mass or less with respect to 100% by mass of the amorphous polyester resin component. Since the ratios of the amorphous polyester resin A and the amorphous polyester resin B are within this range, the toner has excellent offset resistance at low temperatures and high temperatures. As a result, the fixing temperature range in which offset is unlikely to occur, i.e., the offset range, is secured. In addition, the toner of the embodiment also has excellent storage stability.

[0028] When the amorphous polyester resin component contains other amorphous polyester resins, the total proportion of the other amorphous polyester resins is preferably 5 to 20 mass%, and more preferably 10 to 15 mass%, relative to 100 mass% of the amorphous polyester resin component, from the viewpoint of low-temperature fixability.

[0029] The crystalline polyester resin component will now be described. The crystalline polyester resin component may contain one kind of crystalline polyester resin alone, or may contain two or more kinds of crystalline polyester resins. The melting point of the crystalline polyester resin is preferably 60 to 120° C., more preferably 70 to 115° C., and even more preferably 80 to 110° C. When the melting point of the crystalline polyester resin is equal to or higher than the lower limit, the toner has excellent storage stability. When the melting point of the crystalline polyester resin is equal to or lower than the upper limit, the toner has even more excellent low-temperature fixing property. The melting point of the crystalline polyester resin can be measured, for example, as the maximum endothermic peak temperature by a differential scanning calorimeter (DSC).

[0030] The mass average molecular weight of the crystalline polyester resin is 6×10 3 ~1.8×10 4 is preferred, 8×10 3 ~1.4×10 4When the mass average molecular weight of the crystalline polyester resin is equal to or more than the lower limit, the viscosity of the toner during fixing is increased, and low-temperature fixing property is further improved. When the mass average molecular weight of the crystalline polyester resin is equal to or less than the upper limit, the viscosity of the toner during fixing is decreased, and offset is less likely to occur. The mass average molecular weight of the crystalline polyester resin is a value calculated as polystyrene by gel permeation chromatography.

[0031] Examples of the crystalline polyester resin include condensation polymers of divalent or higher alcohols and divalent or higher carboxylic acids. Examples of the dihydric or higher alcohol include ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, 1,4-butenediol, polyoxypropylene, polyoxyethylene, glycerin, pentaerythritol, trimethylolpropane, etc. However, the dihydric or higher alcohol is not limited to these examples. As the dihydric or higher alcohol, 1,4-butanediol and 1,6-hexanediol are preferred. The dihydric or higher alcohol may be used alone or in combination of two or more kinds.

[0032] Examples of the divalent or higher carboxylic acid include adipic acid, oxalic acid, malonic acid, maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, succinic acid, phthalic acid, isophthalic acid, terephthalic acid, sebacic acid, azelaic acid, succinic acid substituted with an alkyl group or an alkenyl group, cyclohexanedicarboxylic acid, trimellitic acid, pyromellitic acid, acid anhydrides thereof, and esters thereof, but the divalent or higher carboxylic acid is not limited to these examples. Examples of succinic acid substituted with an alkyl group or an alkenyl group include succinic acid substituted with an alkyl group or an alkenyl group having 2 to 20 carbon atoms. Examples include n-dodecenylsuccinic acid and n-dodecylsuccinic acid. As the divalent or higher carboxylic acid, fumaric acid is preferred. The divalent or higher carboxylic acids may be used alone or in combination of two or more. However, the crystalline polyester resin is not limited to the condensation polymer of the divalent or higher alcohol and the divalent or higher carboxylic acid exemplified here. The crystalline polyester resin may be used alone or in combination of two or more kinds.

[0033] Other binder resins will now be described. Examples of the other binder resin include styrene-based resins, ethylene-based resins, acrylic-based resins, phenol-based resins, epoxy-based resins, allyl phthalate-based resins, polyamide-based resins, and maleic acid-based resins, but are not limited to these examples. The other binder resins may be used alone or in combination of two or more.

[0034] Styrene-based resins, ethylene-based resins, acrylic-based resins, phenol-based resins, epoxy-based resins, allyl phthalate-based resins, polyamide-based resins, and maleic acid-based resins can be obtained, for example, by polymerizing a single vinyl polymerizable monomer or a plurality of types of vinyl polymerizable monomers. Examples of the vinyl polymerizable monomer include aromatic vinyl monomers, ester monomers, carboxylic acid-containing monomers, and amine monomers. Examples of aromatic vinyl monomers include styrene, methylstyrene, methoxystyrene, phenylstyrene, chlorostyrene, and derivatives thereof. Examples of the ester monomer include methyl acrylate, ethyl acrylate, butyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, and derivatives thereof. Examples of the carboxylic acid-containing monomer include acrylic acid, methacrylic acid, fumaric acid, maleic acid, and derivatives thereof. Examples of the amine monomer include aminoacrylate, acrylamide, methacrylamide, vinylpyridine, vinylpyrrolidone, and derivatives thereof.

[0035] Other binder resins may be obtained by polycondensation of a polymerizable monomer component consisting of an alcohol component and a carboxylic acid component. In polycondensation of the polymerizable monomer component, various assistants such as a chain transfer agent, a crosslinking agent, a polymerization initiator, a surfactant, a flocculating agent, a pH adjuster, and a defoaming agent may be used.

[0036] The release agent will now be described. When the toner base particles contain a releasing agent, the toner is more unlikely to adhere to the roller during fixing, and offset resistance is further improved. Examples of the release agent include aliphatic hydrocarbon waxes such as low molecular weight polyethylene, low molecular weight polypropylene, polyolefin copolymers, polyolefin wax, paraffin wax, Fischer-Tropsch wax, and modified products thereof; vegetable waxes such as candelilla wax, carnauba wax, Japan wax, jojoba wax, and rice wax; animal waxes such as beeswax, lanolin, and spermaceti; mineral waxes such as montan wax, ozokerite, and ceresin; ester waxes; fatty acid amides such as linoleic acid amide, oleic acid amide, and lauric acid amide; functional synthetic waxes; and silicone waxes. The release agents may be used alone or in combination of two or more.

[0037] Among these, the release agent is preferably an ester wax, and the following specific ester wax α is preferred from the viewpoint of the heat resistance and storage stability of the toner: The ester wax α is composed of two or more kinds of ester compounds having different carbon numbers. Ester wax α: a condensation polymer of a first monomer group consisting of at least three kinds of carboxylic acids and a second monomer group consisting of at least two kinds of alcohols.

[0038] Regarding the ester wax α, the first monomer group will be described. The number of types of carboxylic acids in the first monomer group is preferably 7 or less, more preferably 5 or less, and even more preferably 4 or less, in view of easy availability of the ester wax α. Here, the number of carbon atoms of the carboxylic acid having the maximum content in the first monomer group is C n The number of carbon atoms is C n is preferably 19 to 28, more preferably 19 to 24, and further preferably 20 to 24. n When the carbon number C is equal to or more than the lower limit, the heat resistance of the ester wax α is improved. n When it is equal to or less than the upper limit, the toner has further excellent low-temperature fixability.

[0039] Maximum carbon content C n The proportion of the carboxylic acid is preferably 70 to 95 mass%, more preferably 80 to 95 mass%, and even more preferably 85 to 95 mass%, based on 100 mass% of the first monomer group. n When the ratio of the carboxylic acid is equal to or greater than the lower limit, the maximum peak of the carbon number distribution of the ester wax α tends to be located on the high carbon number side, and therefore the toner has excellent heat resistance and storage stability. n When the ratio of the carboxylic acid is equal to or less than the upper limit, the ester wax α is easily available.

[0040] The ratio of the carboxylic acid having 18 or less carbon atoms in the first monomer group is preferably 0 to 5% by mass, and more preferably 0 to 1% by mass, relative to 100% by mass of the first monomer group. When the ratio of the carboxylic acid having 18 or less carbon atoms is equal to or greater than the lower limit, the ester wax α is easily available. When the ratio of the carboxylic acid having 18 or less carbon atoms is equal to or less than the upper limit, the ratio of the ester compound having a relatively low molecular weight in the ester wax α is reduced. As a result, the toner has excellent heat resistance and storage stability. The content of carboxylic acids having each carbon number in the first monomer group can be measured, for example, by mass spectrometry using FD-MS (Field Desorption Mass Spectrometry) for the product obtained after the methanolysis reaction of the ester wax α.

[0041] As the carboxylic acid in the first monomer group, a long-chain carboxylic acid is preferable because the ester wax α is easily available, and a long-chain alkyl carboxylic acid is preferable. The long-chain carboxylic acid is appropriately selected depending on the characteristics, performance, etc. required for the ester wax α. The long-chain carboxylic acid is preferably a long-chain carboxylic acid having 19 to 28 carbon atoms, and more preferably a long-chain carboxylic acid having 20 to 24 carbon atoms. When the carbon number of the long-chain carboxylic acid is equal to or more than the lower limit, the heat resistance of the ester wax α is improved. When the carbon number of the long-chain carboxylic acid is equal to or less than the upper limit, the toner has even better low-temperature fixability. Examples of long-chain alkyl carboxylic acids include palmitic acid, stearic acid, arachidic acid, behenic acid, lignoceric acid, cerotic acid, and montanic acid.

[0042] Regarding the ester wax α, the second monomer group will be described. The number of types of alcohols in the second monomer group is preferably 5 or less, more preferably 4 or less, and even more preferably 3 or less, in view of easy availability of the ester wax α. Here, the number of carbon atoms of the alcohol having the maximum content in the second monomer group is C m The number of carbon atoms is C m is preferably 19 to 28, more preferably 20 to 24, and further preferably 20 to 22. m When the carbon number C is equal to or more than the lower limit, the heat resistance of the ester wax α is improved. m When it is equal to or less than the upper limit, the toner has further excellent low-temperature fixability.

[0043] Maximum carbon content C mThe proportion of the alcohol is preferably 70 to 90% by mass, more preferably 80 to 90% by mass, and even more preferably 85 to 90% by mass, based on 100% by mass of the second monomer group. m When the ratio of the alcohol is equal to or greater than the lower limit, the maximum peak of the carbon number distribution of the ester wax α tends to be located on the high carbon number side. Therefore, the toner has excellent heat resistance and storage stability. m When the alcohol ratio is equal to or less than the upper limit, the ester wax α is easily available.

[0044] The proportion of the alcohol having 18 or less carbon atoms in the second monomer group is preferably 20% by mass or less, more preferably 10 to 20% by mass, and even more preferably 15 to 20% by mass, relative to 100% by mass of the second monomer group. When the proportion of the alcohol having 18 or less carbon atoms is equal to or greater than the lower limit, the ester wax α is easily available. When the proportion of the alcohol having 18 or less carbon atoms is equal to or less than the upper limit, the proportion of ester compounds having relatively low molecular weights in the ester wax α is reduced. As a result, the toner has excellent heat resistance and storage stability. The content of alcohols having each carbon number in the second monomer group can be measured, for example, by subjecting the ester wax α to a methanolysis reaction product and subjecting it to mass spectrometry using FD-MS.

[0045] As the alcohol in the second monomer group, a long-chain alcohol is preferable because the ester wax α is easily available, and a long-chain alkyl alcohol is more preferable. The long-chain alcohol is appropriately selected depending on the characteristics, performance, etc. required for the ester wax α. The long-chain alcohol is preferably a long-chain alcohol having 19 to 28 carbon atoms, and more preferably a long-chain alcohol having 20 to 22 carbon atoms. When the carbon number of the long-chain alcohol is equal to or more than the lower limit, the heat resistance of the ester wax α is improved. When the carbon number of the long-chain alcohol is equal to or less than the upper limit, the toner has even better low-temperature fixability. Examples of long-chain alkyl alcohols include palmityl alcohol, stearyl alcohol, arachidyl alcohol, behenyl alcohol, lignoceryl alcohol, ceryl alcohol, and montanyl alcohol.

[0046] In Ester Wax α, the maximum carbon number C of the ester compounds that make up Ester Wax α is l It is preferable that an ester compound having a carbon number C l is preferably 43 or more, more preferably 43 to 56, still more preferably 43 to 52, particularly preferably 44 to 46, and most preferably 44. l When the number of carbon atoms is equal to or more than the lower limit, the toner has excellent heat resistance and storage stability. l When the amount of the ester wax α is equal to or less than the upper limit, the ester wax α is easily available.

[0047] Carbon number C l The ester compound is represented by the following formula (I): R 1 COOR 2 (I) R in formula (I) 1 and R 2 is an alkyl group. 1 and R 2 The total number of carbon atoms in R is preferably 42 or more, more preferably 42 to 55, still more preferably 42 to 51, particularly preferably 43 to 45, and most preferably 43. 1 and R 2 When the total number of carbon atoms in R is equal to or greater than the lower limit, the toner has excellent heat resistance and storage stability. 1 and R 2 When the total number of carbon atoms of R is equal to or less than the upper limit, the ester wax α is easily available. 1 For example, the carbon number C n The number of carbon atoms in the carboxylic acid is C n It can be controlled by adjusting R 2 For example, the carbon number C m The number of carbon atoms in the alcohol m It can be controlled by adjusting

[0048] Carbon number C l The proportion of the ester compound is preferably 65% ​​by mass or more, more preferably 65 to 90% by mass, further preferably 70 to 90% by mass, and particularly preferably 80 to 90% by mass, based on 100% by mass of the ester wax α. l When the ratio of the ester compound is equal to or more than the lower limit, the maximum peak of the carbon number distribution of the ester wax α becomes sufficiently high, and as a result, the toner has excellent heat resistance and storage stability. Carbon number C l When the proportion of the ester compound is equal to or less than the upper limit, the ester wax α is easily available.

[0049] The carbon number distribution of the ester wax α preferably has only one maximum peak in the region of carbon number 43 or more. In this case, the proportion of ester compounds with relatively low molecular weights is reduced. As a result, the toner has excellent heat resistance and storage stability. In the carbon number distribution of the ester wax α, the position of the maximum peak is preferably in the region of 43 to 56 carbon atoms, more preferably in the region of 44 to 52 carbon atoms, even more preferably in the region of 44 to 46 carbon atoms, and most preferably in the region of 44 carbon atoms. When the position of the maximum peak is in the region of the carbon number equal to or greater than the lower limit, the toner has better heat resistance and storage stability. When the position of the maximum peak is in the region of the carbon number equal to or less than the upper limit, the ester wax α is easily available. The content of the ester compounds having each carbon number in the ester wax α can be measured, for example, by mass spectrometry using FD-MS.

[0050] The melting point of the ester wax α is preferably 60 to 85° C., more preferably 65 to 80° C., and even more preferably 65 to 75° C. When the melting point of the ester wax α is equal to or higher than the lower limit, the toner has excellent heat resistance and storage stability. In addition, offset is unlikely to occur in a high-temperature environment. When the melting point of the ester wax α is equal to or lower than the upper limit, the toner has even better low-temperature fixability. The melting point of the ester wax α can be measured, for example, as the maximum endothermic peak temperature by differential scanning calorimetry (DSC).

[0051] The ester wax α can be synthesized, for example, by esterifying a long-chain carboxylic acid with a long-chain alcohol. In the esterification reaction, it is preferable to use at least three or more types of long-chain alkyl carboxylic acids and at least two or more types of long-chain alkyl alcohols. The carbon number distribution of the ester compounds contained in the ester wax α can be adjusted by adjusting the carbon numbers of the long-chain alkyl carboxylic acids and the long-chain alkyl alcohols and the amounts of each used. The esterification reaction can be carried out, for example, while heating under a nitrogen stream. The esterification reaction product may be dissolved in a solvent containing ethanol, toluene, etc., and further purified by adding a basic aqueous solution such as an aqueous sodium hydroxide solution to separate the organic layer and the aqueous layer. The aqueous layer is removed to obtain the ester wax α. It is preferable to repeat the purification operation several times.

[0052] The colorant will now be described. The colorant is not particularly limited, and examples thereof include carbon black, cyan, yellow, and magenta pigments, dyes, and the like. Examples of carbon black include aniline black, lamp black, acetylene black, furnace black, thermal black, channel black, and ketjen black. Examples of pigments and dyes include Fast Yellow G, Benzidine Yellow, Chrome Yellow, Quinoline Yellow, India Fast Orange, Irgazin Red, Carmine FB, Permanent Bordeaux FRR, Pigment Orange R, Lithol Red 2G, Lake Red C, Rhodamine FB, Rhodamine B Lake, DuPont Oil Red, Phthalocyanine Blue, Pigment Blue, Aniline Blue, Chalcone Blue, Ultramarine Blue, Brilliant Green B, Phthalocyanine Green, Malachite Green Oxalate, Methylene Blue Chloride, Rose Bengal, and Quinacridone. Colorants are indicated by color index numbers, for example, CI Pigment Black 1, 6, 7, CI Pigment Yellow 1, 12, 14, 17, 34, 74, 83, 97, 155, 180, 185, CI Pigment Orange 48, 49, CI Pigment Red 5, 12, 31, 48, 48:1, 48:2, 48:3, 48:4, 48:5, 49, 53, 53:1, 53:2, 53:3 , 57, 57:1, 81, 81:4, 122, 146, 150, 177, 185, 202, 206, 207, 209, 238, 269, CI Pigment Blue 15, 15:1, 15:2, 15:3, 15:4, 15:5, 15:6, 75, 76, 79, CI Pigment Green 1, 7, 8, 36, 42, 58, CI Pigment Violet 1, 19, 42, CI Acid Red 52, etc.

[0053] The other ingredients will now be described. Examples of other components include additives such as charge control agents, surfactants, basic compounds, flocculants, pH adjusters, and antioxidants. However, the additives are not limited to these examples. Any one of the additives may be used alone, or two or more of them may be used in combination.

[0054] The charge control agent will now be described. When the toner base particles contain a charge control agent, the toner is easily transferred onto a recording medium such as paper. Examples of the charge control agent include a metal-containing azo compound, a metal-containing salicylic acid derivative compound, a hydrophobic metal oxide, and a polysaccharide clathrate compound. As the metal-containing azo compound, a complex or complex salt in which the metal is iron, cobalt, or chromium, or a mixture thereof is preferable. As the metal-containing salicylic acid derivative compound and the metal oxide hydrophobic metal, a complex or complex salt in which the metal is zirconium, zinc, chromium, or boron, or a mixture thereof is preferable. As the polysaccharide clathrate compound, a polysaccharide clathrate compound containing aluminum (Al) and magnesium (Mg) is preferable.

[0055] The composition of the toner base particles will be described. The proportion of the crystalline polyester resin component is 10% by mass or less relative to 100% by mass of the toner base particles, and therefore the toner of the embodiment has excellent low-temperature fixing property and charging property in a high-temperature and high-humidity environment. In the first embodiment, the ratio of the crystalline polyester resin component is preferably 5 to 10% by mass, more preferably 5 to 7% by mass, based on 100% by mass of the toner base particles. When the ratio of the crystalline polyester resin component is equal to or more than the lower limit, the low-temperature fixing property at room temperature is more excellent. When the ratio of the crystalline polyester resin component is equal to or less than the upper limit, the toner has more excellent low-temperature fixing property and charging property in a high-temperature and high-humidity environment.

[0056] The ratio of the non-crystalline polyester resin component is preferably 70 to 90% by mass, more preferably 70 to 85% by mass, and even more preferably 70 to 80% by mass, based on 100% by mass of the toner base particles. When the ratio of the non-crystalline polyester resin component is equal to or more than the lower limit, the toner has better low-temperature fixing property and chargeability in a high-temperature and high-humidity environment. When the ratio of the non-crystalline polyester resin component is equal to or less than the upper limit, the toner has better low-temperature fixing property at room temperature.

[0057] When the toner base particles contain a releasing agent, the ratio of the releasing agent is preferably 3 to 15% by mass, more preferably 3 to 13% by mass, and even more preferably 5 to 10% by mass, based on 100% by mass of the toner base particles. When the content of the releasing agent is equal to or more than the lower limit, the toner has better offset resistance. When the content of the releasing agent is equal to or less than the upper limit, the charge amount is easily maintained.

[0058] When the toner base particles contain a colorant, the content of the colorant is preferably 2 to 13% by mass, more preferably 3 to 8% by mass, based on 100% by mass of the toner base particles. When the content of the colorant is equal to or more than the lower limit, the toner has excellent color reproducibility. When the content of the colorant is equal to or less than the upper limit, the dispersibility of the colorant is improved, and the toner has further excellent low-temperature fixability. In addition, the charge amount of the toner is easily controlled.

[0059] The external additives will be described. The external additive may be particles made of an inorganic oxide. The particles made of an inorganic oxide may be surface-treated with a hydrophobizing agent to improve stability. Examples of inorganic oxides include silica, titania, alumina, strontium titanate, titanium oxide, and tin oxide. The external additives may be used alone or in combination of two or more.

[0060] From the viewpoint of the charge amount of the toner, the external additive preferably contains silica particles. From the viewpoint of the amount of toner scattering, the external additive preferably contains at least one selected from the group consisting of strontium titanate and titanium oxide.

[0061] As the silica particles, wet silica is preferred, and hydrophobic silica is more preferred. Wet silica can be produced, for example, by using sodium silicate made from silica sand as a raw material, neutralizing an aqueous solution containing sodium silicate to precipitate silica, which is then filtered and dried (liquid phase method). In contrast, calcined silica (dry silica) is known, which is obtained by reacting silicon tetrachloride in a high-temperature flame. When wet silica is used as an external additive for toner, the charge of the toner is more easily maintained than with calcined silica, which generally has a low moisture content. Hydrophobic silica particles can be obtained, for example, by subjecting surface silanol groups of wet silica to a hydrophobic treatment with silane, silicone, etc. When the hydrophobic silica particles are used as an external additive for a toner, they improve adhesion to the toner base particles.

[0062] The degree of hydrophobicity of the hydrophobic silica can be measured, for example, by the following method. Put 50 ml of ion-exchanged water and 0.2 g of sample into a beaker, and add methanol dropwise from a burette while stirring with a magnetic stirrer. Next, as the methanol concentration in the beaker increases, the powder gradually settles, and the volume percentage of methanol in the mixed solution of methanol and ion-exchanged water at the end point when the entire powder has settled is taken as the degree of hydrophobicity (%).

[0063] The particle size of the silica particles is preferably from 30 to 300 nm, more preferably from 30 to 200 nm, and even more preferably from 30 to 150 nm, from the viewpoint of the charge amount of the toner. The particle size of the silica particles can be measured, for example, by a laser diffraction type particle size distribution measuring device.

[0064] When the toner has an external additive, the content of the external additive is preferably 2 to 15 parts by mass, more preferably 4 to 10 parts by mass, and even more preferably 4 to 8 parts by mass, relative to 100 parts by mass of the toner base particles. When the content of the external additive is equal to or more than the lower limit, the charge amount of the toner is easily ensured to be sufficient. When the content of the external additive is equal to or less than the upper limit, the charge amount of the toner is unlikely to become excessively high. Therefore, the charge amount of the toner is easily maintained at an appropriate level.

[0065] The toner production method will be described. The toner base particles can be produced, for example, by a kneading and pulverizing method or a chemical method. The toner base particles can be used as a toner as they are. When producing a toner containing an external additive, the toner base particles and the external additive are mixed.

[0066] The kneading and pulverizing method will be described. The kneading and pulverizing method may, for example, be a production method including the following mixing step, kneading step, and pulverizing step. The kneading and pulverizing method may further include the following classification step, if necessary. Mixing step: a step of mixing at least a non-crystalline polyester resin A, a non-crystalline polyester resin B, and a crystalline polyester resin to obtain a mixture. Kneading step: a step of melt-kneading the mixture to obtain a kneaded product. Crushing step: a step of pulverizing the kneaded material to obtain a pulverized material. Classification step: a step of classifying the pulverized material.

[0067] In the mixing step, the raw materials of the toner are mixed to obtain a mixture. In the mixing step, a mixer may be used. The mixer is not particularly limited. In the mixing step, a release agent, a colorant, other binder resins, and additives may be used as necessary. In the kneading step, the mixture obtained in the mixing step is melt-kneaded to obtain a kneaded product. A kneader may be used in the kneading step. The kneader is not particularly limited. In the pulverization step, the kneaded product obtained in the kneading step is pulverized to obtain a pulverized product. A pulverizer may be used in the pulverization step. As the pulverizer, various pulverizers such as a hammer mill may be used. In addition, the pulverized product obtained by the pulverizer may be further pulverized. As the pulverizer for further pulverizing the pulverized product, various pulverizers may be used. The pulverized product obtained in the pulverization step may be used as it is as toner base particles, or may be used as toner base particles after a classification step as necessary. In the classification step, the pulverized product obtained in the pulverization step is classified. A classifier may be used in the classification step. The classifier is not particularly limited.

[0068] The chemical method will now be described. In the chemical method, amorphous polyester resin A, amorphous polyester resin B, crystalline polyester resin, and optionally release agents, colorants, other binder resins, and additives are mixed to obtain a mixture. The mixture is then melted and kneaded to obtain a kneaded product. The kneaded product is then pulverized to obtain coarsely granulated medium-sized particles. The medium-sized particles are then mixed with an aqueous medium to prepare a mixture. The mixture is then subjected to mechanical shearing to obtain a fine particle dispersion. Finally, the fine particles are aggregated in the fine particle dispersion to form toner base particles.

[0069] The method of mixing the external additives will be described. The external additive is mixed with the toner base particles by, for example, a mixer. The mixer is not particularly limited. By mixing the external additive with the toner base particles, the external additive adheres to the surfaces of the toner base particles. The external additive may be sieved using a sieving device as necessary. The sieving device is not particularly limited. Various sieving devices can be used.

[0070] The toner according to at least one embodiment of the first aspect described above has excellent low-temperature fixing ability even in a high-temperature and high-humidity environment, and can maintain a sufficient charge amount. In addition, the toner according to the embodiment is less likely to adhere to the roller during fixing, and has excellent offset resistance.

[0071] Next, the toner according to the second embodiment will be described. The toner according to the second embodiment differs from the toner according to the first embodiment mainly in the following points. The proportion of the crystalline polyester resin component is 5% by mass or less relative to 100% by mass of the toner base particles.

[0072] In the toner according to the second embodiment, the ratio of the crystalline polyester resin is 5% by mass or less relative to 100% by mass of the toner base particles, and therefore the chargeability in a high-temperature and high-humidity environment is even better than that of the first embodiment.

[0073] In addition, since the amount of the crystalline polyester resin, which is generally expensive, is reduced, the toner according to the embodiment of the second embodiment can be provided at a low cost. Therefore, the toner according to the embodiment of the second embodiment is advantageous in terms of cost.

[0074] The low temperature fixing property in the second embodiment is not as excellent as that in the first embodiment, but is still as excellent as that of a conventional low temperature fixing toner. It is also possible to achieve a low temperature fixing property superior to that of a conventional low temperature fixing toner. Although the storage stability in the second embodiment is not as excellent as that in the first embodiment, it is still possible to realize storage stability that is sufficiently excellent for practical use.

[0075] In the toner according to the embodiment related to the second implementation, in addition to the ratio of the crystalline polyester resin component, the ratios of the non-crystalline polyester resin A and the non-crystalline polyester resin B are different. Hereinafter, the respective proportions of the crystalline polyester resin component, the non-crystalline polyester resin A, and the non-crystalline polyester resin B in the second embodiment will be described.

[0076] In the second embodiment, the ratio of the amorphous polyester resin A is preferably 90 to 95% by mass relative to 100% by mass of the amorphous polyester resin component. When the ratio of the amorphous polyester resin A is equal to or greater than the lower limit of the above-mentioned numerical range, the toner has excellent low-temperature fixing properties at room temperature. When the ratio of the amorphous polyester resin A is equal to or less than the upper limit of the above-mentioned numerical range, the toner has excellent storage stability.

[0077] In the second embodiment, the ratio of the amorphous polyester resin B is preferably 5 to 10% by mass relative to 100% by mass of the amorphous polyester resin component. When the ratio of the amorphous polyester resin B is equal to or greater than the lower limit of the above-mentioned numerical range, the toner has excellent storage stability. When the ratio of the amorphous polyester resin B is equal to or greater than the lower limit of the above-mentioned numerical range, the toner has excellent low-temperature fixing property at room temperature.

[0078] In the second embodiment, the melting temperature of the amorphous polyester resin B is preferably 130 to 160° C., more preferably 130 to 150° C. When the melting temperature of the amorphous polyester resin B is equal to or higher than the lower limit of the above-mentioned numerical range, the toner has excellent offset resistance at high temperatures. The toner also has excellent storage stability. When the melting temperature of the amorphous polyester resin B is equal to or lower than the upper limit of the above-mentioned numerical range, the toner has even more excellent low-temperature fixing property.

[0079] Other configurations than those described in detail in the second embodiment above are common to the first and second embodiments. The toner according to the second embodiment can be manufactured in the same manner as the toner according to the first embodiment, except that the composition of the toner base particles is different. Therefore, the description of these common contents will be omitted in the second aspect.

[0080] A toner cartridge according to an embodiment will be described below. The toner cartridge of the embodiment contains the toner of the above-mentioned embodiment. The toner of this embodiment may be either the toner according to the first embodiment or the toner according to the second embodiment. For example, the toner cartridge has a container, and the toner of the embodiment is contained in the container. The container is not particularly limited, and various containers applicable to image forming apparatuses can be used. The toner of the embodiment may be used as a one-component developer, or may be used in combination with a carrier as a two-component developer.

[0081] Hereinafter, an image forming apparatus according to an embodiment will be described with reference to the drawings. FIG. 1 is a diagram illustrating an example of a schematic structure of an image forming apparatus according to an embodiment. Image forming apparatus 20 of the embodiment has an apparatus main body including intermediate transfer belt 7, first image forming unit 17A and second image forming unit 17B arranged in this order on intermediate transfer belt 7, and fixing device 21 arranged downstream thereof. Along the running direction X of intermediate transfer belt 7, i.e., along the proceeding direction of the image forming process, first image forming unit 17A is arranged downstream of second image forming unit 17B. Fixing device 21 is arranged downstream of first image forming unit 17A.

[0082] The first image forming unit 17A has a photoconductor drum 1a, a cleaning device 16a, a charging device 2a, an exposure device 3a, a first developing device 4a, and a primary transfer roller 8a. The cleaning device 16a, the charging device 2a, the exposure device 3a, and the first developing device 4a are provided in this order along the rotation direction of the photoconductor drum 1a. The primary transfer roller 8a is provided on the photoconductor drum 1a via the intermediate transfer belt 7 so as to face the photoconductor drum 1a. A primary transfer power source 14a is connected to the primary transfer roller 8a. The second image forming unit 17B has a photoconductor drum 1b, a cleaning device 16b, a charging device 2b, an exposure device 3b, a second developing device 4b, and a primary transfer roller 8b. The cleaning device 16b, the charging device 2b, the exposure device 3b, and the second developing device 4b are provided in this order along the rotation direction of the photoconductor drum 1b. The primary transfer roller 8b is provided on the photoconductor drum 1b via the intermediate transfer belt 7 so as to face the photoconductor drum 1b. A primary transfer power source 14b is connected to the primary transfer roller 8b.

[0083] The toner of the above-described embodiment is contained in the first developing device 4a and the second developing device 4b. The toner of this embodiment may be either the toner of the first embodiment or the toner of the second embodiment. In the image forming apparatus according to the other embodiment, the toner may be supplied from a toner cartridge (not shown). A secondary transfer roller 9 and a backup roller 10 are disposed downstream of the first image forming unit 17A so as to face each other across the intermediate transfer belt 7. A secondary transfer power source 15 is connected to the secondary transfer roller 9.

[0084] The fixing device 21 is provided downstream of the first image forming unit 17A. The fixing device 21 has a heat roller 11 and a press roller 12 arranged to face each other. The fixing device 21 is a device for fixing the toner onto the recording medium. The toner image is fixed onto the paper by applying heat and pressure by the heat roller 11 and the press roller 12.

[0085] The image forming apparatus 20 forms an image, for example, in the following manner. First, the photoconductor drum 1b is uniformly charged by the charging device 2b. Next, the exposure device 3b performs exposure to form an electrostatic latent image. Next, development is performed with the toner of the embodiment supplied from the developing device 4b to obtain a second toner image. Next, the photoconductor drum 1a is uniformly charged by the charging device 2a. Next, the exposure device 3a performs exposure based on the first image information (second toner image) to form an electrostatic latent image. Next, development is performed with the toner of the embodiment supplied from the developing device 4a to obtain a first toner image. The second toner image and the first toner image are transferred in this order onto the intermediate transfer belt 7 by primary transfer rollers 8a and 8b. The image in which the second toner image and the first toner image are layered in this order on the intermediate transfer belt 7 is secondarily transferred onto a recording medium (not shown) via a secondary transfer roller 9 and a backup roller 10. As a result, an image in which the first toner image and the second toner image are layered in this order is formed on the recording medium.

[0086] The image forming apparatus shown in Fig. 1 is a type that fixes a toner image. However, the image forming apparatus according to the embodiment is not limited to this type. The image forming apparatus according to other embodiments may be, for example, an inkjet type. EXAMPLES

[0087] The following examples are provided to more specifically explain the embodiments.

[0088] The glass transition temperature (Tg), melting temperature (Tm) and weight average molecular weight (Mw) of the amorphous polyester resin A used in each example are as follows. Amorphous polyester resin A1 (Tg: 50°C, Tm: 98°C, Mw: 7×10 3 ) Amorphous polyester resin A2 (Tg: 48°C, Tm: 95°C, Mw: 6×10 3 ) Amorphous polyester resin A3 (Tg: 54°C, Tm: 105°C, Mw: 1×10 4 ) Amorphous polyester resin A4 (Tg: 41°C, Tm: 90°C, Mw: 5×10 4 )

[0089] The melting temperature (Tm), glass transition temperature (Tg) and weight average molecular weight (Mw) of the amorphous polyester resin B used in each example are as follows. Amorphous polyester resin B1 (Tm: 135°C, Tg: 56°C, Mw: 4.5×10 4 ) Amorphous polyester resin B2 (Tm: 145°C, Tg: 57°C, Mw: 5×10 4 ) Amorphous polyester resin B3 (Tm: 120°C, Tg: 54°C, Mw: 3.5×10 4 ) Amorphous polyester resin B4 (Tm: 130°C, Tg: 55°C, Mw: 4×10 4 )

[0090] The glass transition temperature of the crystalline polyester resin C used in each example is 60° C. The melting point of the crystalline polyester resin C is 100° C. The mass average molecular weight (Mw) of the crystalline polyester resin C is 9.5×10 3 It is.

[0091] The release agents used in each example are as follows: Release agent A: Ester wax (melting point: 72°C). Release agent B: Ester wax (melting point: 70°C).

[0092] The toner of Example 1 was prepared as follows. First, the raw materials of the toner base particles listed below were put into a Henschel mixer (manufactured by Mitsui Mining Co., Ltd.) and mixed. Furthermore, the mixture of raw materials of the toner base particles was melted and kneaded in a twin-screw extruder. After cooling the melted and kneaded product, it was coarsely pulverized in a hammer mill. The coarsely pulverized product was finely pulverized in a jet pulverizer. The finely pulverized product was classified to obtain toner base particles. The volume average diameter of the toner base particles was 7 μm. The volume average diameter of the toner base particles was measured by a laser diffraction particle size distribution measuring device (manufactured by Shimadzu Corporation (SALD7000)). The composition of the raw materials for the toner base particles is shown below. Non-crystalline polyester resin A1 64 parts by mass Non-crystalline polyester resin B1 16 parts by mass Crystalline polyester resin C 10 parts by mass Release agent A 3 parts by weight Carbon black 6 parts by weight Charge control agent (polysaccharide inclusion compound containing Al and Mg) 1 part by mass

[0093] Next, external additives having the following composition were mixed with 100 parts by mass of the toner base particles of Example 1 using a Henschel mixer to produce the toner of Example 1. Silica particles 3.8 parts by weight Titanium oxide 0.5 parts by mass

[0094] The toner of Example 2 was prepared as follows. First, toner base particles of Example 2 were produced in the same manner as in Example 1, except that the composition of the raw materials for the toner base particles was changed as follows. Next, the toner base particles and external additives were mixed in the same manner as in Example 1, to produce the toner of Example 2. Non-crystalline polyester resin A2 64 parts by mass Non-crystalline polyester resin B2 16 parts by mass Crystalline polyester resin C 10 parts by mass Release agent A 3 parts by weight Carbon black 6 parts by weight Charge control agent (polysaccharide inclusion compound containing Al and Mg) 1 part by mass

[0095] The toner of Example 3 was prepared as follows. First, toner base particles of Example 3 were produced in the same manner as in Example 1, except that the composition of the raw materials for the toner base particles was changed as follows. Next, the toner base particles and external additives were mixed in the same manner as in Example 1, to produce the toner of Example 3. Non-crystalline polyester resin A2 68 parts by mass Non-crystalline polyester resin B2 12 parts by mass Crystalline polyester resin C 10 parts by mass Release agent A 3 parts by weight Carbon black 6 parts by weight Charge control agent (polysaccharide inclusion compound containing Al and Mg) 1 part by mass

[0096] The toner of Example 4 was prepared as follows. First, the toner base particles of Example 4 were produced in the same manner as in Example 1, except that the composition of the raw materials for the toner base particles was changed as follows. Next, the toner base particles and external additives were mixed in the same manner as in Example 1, to produce the toner of Example 4. Non-crystalline polyester resin A2 72 parts by mass Non-crystalline polyester resin B2 8 parts by mass Crystalline polyester resin C 10 parts by mass Release agent B 3 parts by weight Carbon black 6 parts by weight Charge control agent (polysaccharide inclusion compound containing Al and Mg) 1 part by mass

[0097] The toner of Example 5 was prepared as follows. First, the toner base particles of Example 5 were produced in the same manner as in Example 1, except that the composition of the raw materials for the toner base particles was changed as follows. Next, the toner base particles and external additives were mixed in the same manner as in Example 1, to produce the toner of Example 5. Non-crystalline polyester resin A2 76.5 parts by mass Non-crystalline polyester resin B2 8.5 parts by mass Crystalline polyester resin C 5 parts by mass Release agent B 3 parts by weight Carbon black 6 parts by weight Charge control agent (polysaccharide inclusion compound containing Al and Mg) 1 part by mass

[0098] The toner of Example 6 was prepared as follows. First, the toner base particles of Example 6 were produced in the same manner as in Example 1, except that the composition of the raw materials for the toner base particles was changed as follows. Next, the toner base particles and external additives were mixed in the same manner as in Example 1, to produce the toner of Example 6. Non-crystalline polyester resin A1 76 parts by mass Non-crystalline polyester resin B1 4 parts by mass Crystalline polyester resin C 10 parts by mass Release agent B 3 parts by weight Carbon black 6 parts by weight Charge control agent (polysaccharide inclusion compound containing Al and Mg) 1 part by mass

[0099] The toner of Example 7 was prepared as follows. First, toner base particles of Example 7 were produced in the same manner as in Example 1, except that the composition of the raw materials for the toner base particles was changed as follows. Next, the toner base particles and external additives were mixed in the same manner as in Example 1, to produce the toner of Example 7. Non-crystalline polyester resin A1 64 parts by mass Non-crystalline polyester resin B3 16 parts by weight Crystalline polyester resin C 10 parts by mass Release agent B 3 parts by weight Carbon black 6 parts by weight Charge control agent (polysaccharide inclusion compound containing Al and Mg) 1 part by mass

[0100] The toner of Example 8 was prepared as follows. First, the toner base particles of Example 8 were produced in the same manner as in Example 1, except that the composition of the raw materials for the toner base particles was changed as follows. Next, the toner base particles and external additives were mixed in the same manner as in Example 1, to produce the toner of Example 8. Non-crystalline polyester resin A1 76.5 parts by mass Non-crystalline polyester resin B1 8.5 parts by mass Crystalline polyester resin C 5 parts by mass Release agent A 3 parts by weight Carbon black 6 parts by weight Charge control agent (polysaccharide inclusion compound containing Al and Mg) 1 part by mass

[0101] The toner of Example 9 was prepared as follows. First, the toner base particles of Example 9 were produced in the same manner as in Example 1, except that the composition of the raw materials for the toner base particles was changed as follows. Next, the toner base particles and external additives were mixed in the same manner as in Example 1, to produce the toner of Example 9. Non-crystalline polyester resin A2 76.5 parts by mass Non-crystalline polyester resin B2 8.5 parts by mass Crystalline polyester resin C 5 parts by mass Release agent A 3 parts by weight Carbon black 6 parts by weight Charge control agent (polysaccharide inclusion compound containing Al and Mg) 1 part by mass

[0102] The toner of Example 10 was prepared as follows. First, the toner base particles of Example 10 were produced in the same manner as in Example 1, except that the composition of the raw materials for the toner base particles was changed as follows. Next, the toner base particles and external additives were mixed in the same manner as in Example 1, to produce the toner of Example 10. Non-crystalline polyester resin A2 78.3 parts by mass Non-crystalline polyester resin B2 8.7 parts by mass Crystalline polyester resin C 3 parts by mass Release agent A 3 parts by weight Carbon black 6 parts by weight Charge control agent (polysaccharide inclusion compound containing Al and Mg) 1 part by mass

[0103] The toner of Example 11 was prepared as follows. First, toner base particles of Example 11 were produced in the same manner as in Example 1, except that the composition of the raw materials for the toner base particles was changed as follows. Next, the toner base particles and external additives were mixed in the same manner as in Example 1, to produce the toner of Example 11. Non-crystalline polyester resin A2 78.3 parts by mass Non-crystalline polyester resin B2 8.7 parts by mass Crystalline polyester resin C 3 parts by mass Release agent A 3 parts by weight Carbon black 6 parts by weight Charge control agent (polysaccharide inclusion compound containing Al and Mg) 1 part by mass

[0104] The toner of Example 12 was prepared as follows. First, toner base particles of Example 12 were produced in the same manner as in Example 1, except that the composition of the raw materials for the toner base particles was changed as follows. Next, the toner base particles and external additives were mixed in the same manner as in Example 1, to produce the toner of Example 12. Non-crystalline polyester resin A2 80.8 parts by mass Non-crystalline polyester resin B2 4.2 parts by mass Crystalline polyester resin C 5 parts by mass Release agent A 3 parts by weight Carbon black 6 parts by weight Charge control agent (polysaccharide inclusion compound containing Al and Mg) 1 part by mass

[0105] The toner of Example 13 was prepared as follows. First, toner base particles of Example 13 were produced in the same manner as in Example 1, except that the composition of the raw materials for the toner base particles was changed as follows. Next, the toner base particles and external additives were mixed in the same manner as in Example 1 to produce the toner of Example 13. Non-crystalline polyester resin A1 76 parts by mass Non-crystalline polyester resin B1 4 parts by mass Crystalline polyester resin C 10 parts by mass Release agent A 3 parts by weight Carbon black 6 parts by weight Charge control agent (polysaccharide inclusion compound containing Al and Mg) 1 part by mass

[0106] The toner of Example 14 was prepared as follows. First, toner base particles of Example 14 were produced in the same manner as in Example 1, except that the composition of the raw materials for the toner base particles was changed as follows. Next, the toner base particles and external additives were mixed in the same manner as in Example 1, to produce the toner of Example 14. Non-crystalline polyester resin A4 68 parts by weight Non-crystalline polyester resin B3 17 parts by mass Crystalline polyester resin C 5 parts by mass Release agent A 3 parts by weight Carbon black 6 parts by weight Charge control agent (polysaccharide inclusion compound containing Al and Mg) 1 part by mass

[0107] The toner of Comparative Example 1 was produced as follows. First, toner base particles of Comparative Example 1 were produced in the same manner as in Example 1, except that the composition of the raw materials for the toner base particles was changed as follows. Next, the toner base particles and external additives were mixed in the same manner as in Example 1, to produce the toner of Comparative Example 1. Non-crystalline polyester resin A2 60 parts by mass Non-crystalline polyester resin B1 15 parts by mass Crystalline polyester resin C 15 parts by mass Release agent B 3 parts by weight Carbon black 6 parts by weight Charge control agent (polysaccharide inclusion compound containing Al and Mg) 1 part by mass

[0108] The toner of Comparative Example 2 was produced as follows. First, toner base particles of Comparative Example 2 were produced in the same manner as in Example 1, except that the composition of the raw materials for the toner base particles was changed as follows. Next, the toner base particles and external additives were mixed in the same manner as in Example 1, to produce the toner of Comparative Example 2. Non-crystalline polyester resin A2 56 parts by mass Non-crystalline polyester resin B2 14 parts by mass Crystalline polyester resin C 20 parts by mass Release agent B 3 parts by weight Carbon black 6 parts by weight Charge control agent (polysaccharide inclusion compound containing Al and Mg) 1 part by mass

[0109] The toner of Comparative Example 3 was produced as follows. First, toner base particles of Comparative Example 3 were produced in the same manner as in Example 1, except that the composition of the raw materials for the toner base particles was changed as follows. Next, the toner base particles and external additives were mixed in the same manner as in Example 1, to produce the toner of Comparative Example 3. Non-crystalline polyester resin A1 56 parts by mass Non-crystalline polyester resin B1 24 parts by mass Crystalline polyester resin C 10 parts by mass Release agent B 3 parts by weight Carbon black 6 parts by weight Charge control agent (polysaccharide inclusion compound containing Al and Mg) 1 part by mass

[0110] The toner of Comparative Example 4 was produced as follows. First, toner base particles of Comparative Example 4 were produced in the same manner as in Example 1, except that the composition of the raw materials for the toner base particles was changed as follows. Next, the toner base particles and external additives were mixed in the same manner as in Example 1, to produce the toner of Comparative Example 4. Non-crystalline polyester resin A3 64 parts by weight Non-crystalline polyester resin B4 16 parts by weight Crystalline polyester resin C 10 parts by mass Release agent B 3 parts by weight Carbon black 6 parts by weight Charge control agent (polysaccharide inclusion compound containing Al and Mg) 1 part by mass

[0111] The toner of Comparative Example 5 was produced as follows. First, toner base particles of Comparative Example 5 were produced in the same manner as in Example 1, except that the composition of the raw materials for the toner base particles was changed as follows. Next, the toner base particles and external additives were mixed in the same manner as in Example 1, to produce the toner of Comparative Example 5. Non-crystalline polyester resin A2 60 parts by mass Non-crystalline polyester resin B4 15 parts by mass Crystalline polyester resin C 15 parts by mass Release agent A 3 parts by weight Carbon black 6 parts by weight Charge control agent (polysaccharide inclusion compound containing Al and Mg) 1 part by mass

[0112] The toner of Comparative Example 6 was produced as follows. First, toner base particles of Comparative Example 6 were produced in the same manner as in Example 1, except that the composition of the raw materials for the toner base particles was changed as follows. Next, the toner base particles and external additives were mixed in the same manner as in Example 1, to produce the toner of Comparative Example 6. Non-crystalline polyester resin A3 68 parts by mass Non-crystalline polyester resin B4 17 parts by weight Crystalline polyester resin C 5 parts by mass Release agent A 3 parts by weight Carbon black 6 parts by weight Charge control agent (polysaccharide inclusion compound containing Al and Mg) 1 part by mass

[0113] The method for measuring the glass transition temperature (Tg) of non-crystalline polyester resins A and B will be explained. The glass transition temperature (Tg) was measured using a DSC Q2000 (manufactured by TA Instruments) under the following measurement conditions: Sample size: 5 mg. Lid and pan: Alumina. Heating rate: 10℃ / min. Measurement method: The sample is heated from 20°C to 160°C at a heating rate of 10°C / min. The sample heated to 160°C is then cooled to below 20°C. The sample is heated again to obtain a curve observed in the temperature range of 30 to 60°C. Tangents are drawn to both the low-temperature and high-temperature sides of this curve, and the temperature at the intersection of the two tangents is taken as the glass transition temperature (Tg).

[0114] The method for measuring the melting temperature (Tm) of the amorphous polyester resins A and B will be described. The toner of each example was pressed with a pressure machine and molded into pellets. The melting temperatures (Tm) of the amorphous polyester resins A and B were measured for the pellets using a flow tester "CFT-500D (manufactured by Shimadzu Corporation)" under the following conditions. Measurement start temperature: 30℃ End of measurement temperature: 200℃ Load: 10kgf Heating rate: 10℃ / min In the flow tester, the temperature corresponding to the midpoint (1 / 2) between the flow start temperature at which melting and flowing begins and the flow end temperature at which the entire sample melts and flows was defined as the melting temperature (Tm).

[0115] The method for measuring the melting point of the release agent, crystalline polyester resin C, will be described. The melting point of the release agent was measured using a DSC Q2000 (manufactured by TA Instruments) under the following measurement conditions: Sample size: 5 mg. Lid and pan: Alumina. Heating rate: 10℃ / min. Measurement method: The sample was heated from 20°C to 200°C. The sample was then cooled to below 20°C. The sample was heated again, and the maximum endothermic peak temperature measured in the temperature range of about 55 to 80°C was taken as the melting point. The melting point of the crystalline polyester resin C was also measured in the same manner as above. However, the sample was heated again, and the maximum endothermic peak temperature measured in the temperature range of about 75 to 120° C. was taken as the melting point of the crystalline polyester resin C.

[0116] The release agent A corresponds to the ester wax α described in the embodiment, whereas the release agent B does not correspond to the ester wax α described in the embodiment. The synthesis of release agent A, which is an example of the ester wax α, will be described. Into a four-neck flask equipped with a stirrer, a thermocouple, and a nitrogen inlet tube, 80 parts by mass of at least three or more long-chain alkyl carboxylic acids and 20 parts by mass of at least three or more long-chain alkyl alcohols were put. Under a nitrogen gas flow, an esterification reaction was carried out at 220°C to obtain a reaction product. A mixed solvent of toluene and ethanol was added to the obtained reaction product to dissolve the reaction product. Furthermore, an aqueous sodium hydroxide solution was added to the flask and stirred at 70°C for 30 minutes. After standing for another 30 minutes, the contents of the flask were separated into an organic layer and an aqueous layer, and the aqueous layer was removed from the contents. Thereafter, ion-exchanged water was added to the flask and stirred at 70°C for 30 minutes. The flask was left standing for 30 minutes, the contents in the flask were separated into an aqueous layer and an organic layer, and the aqueous layer was removed from the contents. This operation was repeated five times. The solvent was distilled off from the organic layer of the contents in the flask under reduced pressure conditions to obtain an ester wax, i.e., a release agent A.

[0117] The long chain alkyl carboxylic acids used were as follows: Palmitic acid (C 16 H 32 O2) Stearic acid (C 18 H 36 O2) Arachidic acid (C 20 H 40 O2) Behenic acid (C 22 H 44 O2) Lignoceric acid (C 24 H 48 O2) Cerotin acid (C 26 H 52 O2) Montanic acid (C 28 H 56 O2)

[0118] The long chain alkyl alcohols used were as follows: Palmityl alcohol (C 16 H 34 O) Stearyl alcohol (C 18 H 38 O) Arachidyl alcohol (C 20 H 42 O) Behenyl alcohol (C 22 H 46 O) Lignoceryl alcohol (C 24 H 50 O) Seryl alcohol (C 26 H 54 O) Montanyl alcohol (C 28 H 58 O)

[0119] A method for measuring the carbon number distribution (proportion of ester compounds with each carbon number) of ester compounds constituting the ester wax will be described. 0.5 g of the toner of each example was weighed and placed in an Erlenmeyer flask. Next, 2 mL of methylene chloride was added to the Erlenmeyer flask to dissolve the toner. Furthermore, 4 mL of hexane was added to the Erlenmeyer flask to obtain a mixed liquid. The mixed liquid was filtered to separate into a filtrate and an insoluble matter. The solvent was distilled off from the filtrate under a nitrogen stream to obtain a precipitate. For this precipitate, the carbon number distribution of the ester compound in the ester wax extracted from the toner was measured.

[0120] The proportion of ester compounds with each carbon number was measured using an FD-MS "JMS-T100GC (manufactured by JEOL Ltd.)" under the following measurement conditions. Sample concentration: 1 mg / ml (solvent: chloroform). Cathode voltage:-10kv. Spectral recording interval: 0.4 s. Measurement mass range (m / z): 10 to 2000.

[0121] The total ionic strength of the ester compounds with each carbon number obtained in the measurement was set to 100. The relative value of the ionic strength of the ester compound with each carbon number to the total was calculated. This relative value was taken as the proportion of the ester compounds with each carbon number in the ester wax. The number of carbon atoms in the ester compound with the maximum relative value was determined as C l It was decided.

[0122] The analytical methods for the first and second monomer groups will be described. Methanolysis reaction was carried out for 3 hours at 70°C for 1 g of each ester wax. Mass spectrometry was carried out on the products after the methanolysis reaction to determine the content of long-chain alkyl carboxylic acids with each carbon number and the content of long-chain alkyl alcohols with each carbon number.

[0123] A method for measuring the carbon number distribution of the carboxylic acids constituting the first monomer group and the alcohols constituting the second monomer group will be described. The proportion of carboxylic acids with each carbon number and the proportion of alcohols with each carbon number were measured using an FD-MS "JMS-T100GC (manufactured by JEOL Ltd.)" under the following measurement conditions. Sample concentration: 1 mg / ml (solvent: chloroform). Cathode voltage:-10kv. Spectral recording interval: 0.4 s. Measurement mass range (m / z): 10 to 2000.

[0124] The sum of the ionic intensities of the carboxylic acids with each carbon number obtained in the measurement was set to 100. The relative values ​​of the ionic intensities of the carboxylic acids with each carbon number to the total were calculated. These relative values ​​were taken as the proportions of the carboxylic acids with each carbon number in the ester wax. The number of carbon atoms in the carboxylic acid with the maximum relative value was designated as C n It was decided. Similarly, the total ion intensity of the alcohols with each carbon number obtained in the measurement was set to 100. The relative value of the ion intensity of the alcohols with each carbon number to the total was calculated. This relative value was taken as the proportion of the alcohols with each carbon number in the ester wax. The carbon number in the alcohol with the carbon number that gave the maximum relative value was designated as C m It was decided.

[0125] For release agent A, the carbon number distribution of the ester wax had only one maximum peak in the region of carbon numbers 43 or more. l is 44, and the carbon number C of the carboxylic acid, which is the maximum content in the first monomer group, is n is 22, and the carbon number C of the alcohol with the maximum content in the second monomer group is m was 22.

[0126] The developer of the embodiment will be described. 100 parts by mass of the ferrite carrier and 9 parts by mass of the toner of each example were stirred in a Turbula mixer to obtain a developer of each example.

[0127] A method for evaluating the low-temperature fixability at room temperature will be described. Each developer was left to stand overnight (at least 8 hours) in a room temperature environment, and then housed in a toner cartridge. This toner cartridge was placed in an image forming apparatus for evaluating low-temperature fixing properties. The image forming apparatus for evaluating low-temperature fixing properties was a commercially available e-studio6530c (manufactured by Toshiba Tec) with the following two modifications: The fixing temperature can be adjusted from 100°C to 200°C in 0.1°C increments. -The fixing speed can be changed and set. Using an image forming apparatus for evaluating low-temperature fixing properties, the fixing temperature was set to 150° C., the fixing speed was set to 75 mm / sec, and the toner adhesion amount was set to 1.5 mg / cm 2 Then, the fixing speed was sequentially set to 150 mm / sec and 225 mm / sec, and the toner adhesion amount was 1.5 mg / cm under each fixing speed condition. 2 Ten solid images were obtained. When no offset or image peeling due to non-fixing occurred in any of the 10 solid images at each fixing speed, the fixing temperature was lowered by 5°C, and a solid image was obtained in the same manner as above. This operation was repeated to determine the lowest fixing temperature at which image peeling did not occur in the solid image, and this lowest temperature was determined as the minimum fixing temperature of the toner. When the minimum fixing temperature was 125°C or lower, the low-temperature fixability at room temperature was evaluated as pass (○). When the minimum fixing temperature was higher than 125°C, the low-temperature fixability at room temperature was evaluated as fail (×).

[0128] A method for evaluating low-temperature fixability under a high-temperature and high-humidity environment will be described. The minimum fixing temperature was determined at each fixing speed in the same manner as in the evaluation method for low-temperature fixing property at room temperature, except that the developer of each example was left to stand overnight (at least 8 hours or more) in an environment with a temperature of 30°C and a humidity of 85%, and then housed in a toner cartridge. When the minimum fixing temperature was 125°C or lower, the low-temperature fixing property in a high-temperature and high-humidity environment was evaluated as pass (○). When the minimum fixing temperature was higher than 125°C, the low-temperature fixing property in a high-temperature and high-humidity environment was evaluated as fail (×).

[0129] A method for evaluating the electrostatic charge property under a high temperature and high humidity environment will be described. 100 g of each developer was placed in a polyethylene bottle and left to stand overnight (at least 8 hours) in an environment with a temperature of 30°C and humidity of 85%. After that, the charge amount was measured using a suction blow-off immediately after stirring for 5 minutes with a Turbula mixer. When the charge amount was -6.0 μC / g or less, the chargeability was evaluated as pass (◯). When the charge amount was in the range of more than -6.0 μC / g to -3.0 μC / g or less, the chargeability was evaluated as pass (△). When the charge amount was higher than -3.0 μC / g, the chargeability was evaluated as fail (×).

[0130] The method for evaluating the storage stability will be described. The toner of each example was left to stand at 55°C for 10 hours. After being left to stand at 55°C for 10 hours, 15 g of the toner of each example was sieved through a mesh with 355 μm openings, and the toner remaining on the mesh was weighed. The smaller the amount of toner remaining on the mesh, the better the storage stability. When the amount of toner remaining on the mesh was 3 g or less, the storage stability was evaluated as acceptable (○). When the amount of toner remaining on the mesh was in the range of more than 3 g and not more than 5 g, the storage stability was evaluated as acceptable (△). When the amount of toner remaining on the mesh was more than 5 g, the storage stability was evaluated as unacceptable (×).

[0131] Tables 1 and 2 show the evaluation results of the low-temperature fixing property at room temperature, the low-temperature fixing property in a hot and humid environment, the electrostatic property, and the storage stability of each example of the toner.

[0132] [Table 1]

[0133] [Table 2]

[0134] In Tables 1 and 2, Tg is the glass transition temperature of amorphous polyester resin A. Tm is the melting temperature of amorphous polyester resin B. a is the ratio of amorphous polyester resin A to 100% by mass of the amorphous polyester resin component. b is the ratio of amorphous polyester resin B to 100% by mass of the amorphous polyester resin component. c is the ratio of the crystalline polyester resin component to 100% by mass of the toner base particles.

[0135] The toners of Examples 1 to 14 were all excellent in the evaluation results of low-temperature fixability at room temperature, low-temperature fixability in a high-temperature and high-humidity environment, and chargeability. The toners of Examples 1 to 5 also had excellent storage stability. In contrast, the toners of Comparative Examples 1 to 6 did not reach the pass standard simultaneously for all of the low-temperature fixability at room temperature, the low-temperature fixability in a hot and humid environment, and the chargeability.

[0136] The toners of Examples 8 to 12 and 14 all have a ratio of 5% by mass or less of the crystalline polyester resin component relative to 100% by mass of the toner base particles. Therefore, the chargeability in a high temperature and high humidity environment was better than that of the toners of Examples 1 to 7. The storage stability of Example 14 was inferior to that of the other Examples, but was still at a level sufficient for practical use.

[0137] Although some embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included in the scope of the invention and its equivalents described in the claims, as well as in the scope and spirit of the invention. [Explanation of symbols]

[0138] 1a...photosensitive drum, 2a...charging device, 3a...exposure device, 4a...first developing device, 5...heat source, 7...intermediate transfer belt, 8a...primary transfer roller, 9...secondary transfer roller, 10...backup roller, 11...heat roller, 12...press roller, 14a...primary transfer power supply, 15...secondary transfer power supply, 16a...cleaning device, 17A...first image forming unit, 20...image forming device, 21...fixing device.

Claims

1. The toner has base particles containing a crystalline polyester resin component, a non-crystalline polyester resin component, and an ester wax, The amorphous polyester resin component contains at least two or more types of amorphous polyester resins, Among the plurality of non-crystalline polyester resins, the non-crystalline polyester resin A having the maximum content has a glass transition temperature of 52° C. or less; Among the plurality of amorphous polyester resins, at least one amorphous polyester resin B other than the amorphous polyester resin A has a melting temperature of 100° C. or higher; The content of the non-crystalline polyester resin A is 80% by mass or more relative to 100% by mass of the non-crystalline polyester resin component, The content of the non-crystalline polyester resin B is 20% by mass or less relative to 100% by mass of the non-crystalline polyester resin component, a content ratio of the crystalline polyester resin component is 10% by mass or less with respect to 100% by mass of the toner base particles, the ester wax is a condensation polymer of a first monomer group consisting of at least three kinds of carboxylic acids and a second monomer group consisting of at least two kinds of alcohols, The carbon number C of the carboxylic acid having the maximum content in the first monomer group ｎ is 19 to 28, The carbon number C of the alcohol having the largest content in the second monomer group ｍ A toner having a molecular weight of 19 to 28.

2. 2. The toner according to claim 1, wherein a content of the non-crystalline polyester resin A is 90% by mass or less with respect to 100% by mass of the non-crystalline polyester resin component.

3. 3. The toner according to claim 1, wherein a content of the non-crystalline polyester resin B is 10% by mass or more relative to 100% by mass of the non-crystalline polyester resin component.

4. The toner according to claim 1 , wherein the content of the crystalline polyester resin component is 5% by mass or less with respect to 100% by mass of the toner base particles.

5. The toner according to claim 4, wherein a content of the non-crystalline polyester resin A is 90% by mass or more with respect to 100% by mass of the non-crystalline polyester resin component.

6. The toner according to claim 4 or 5, wherein a content of the non-crystalline polyester resin B is 10% by mass or less with respect to 100% by mass of the non-crystalline polyester resin component.

7. The toner according to any one of claims 4 to 6, wherein the non-crystalline polyester resin B has a melting temperature of 130°C or higher.

8. 8. The toner according to claim 4, wherein the content of the non-crystalline polyester resin A is 95% by mass or less with respect to 100% by mass of the non-crystalline polyester resin component.

9. The toner according to any one of claims 4 to 8, wherein the content of the non-crystalline polyester resin B is 5% by mass or more relative to 100% by mass of the non-crystalline polyester resin component.

10. A toner cartridge containing the toner according to any one of claims 1 to 9.

11. An image forming apparatus containing the toner according to any one of claims 1 to 9.

Images