toner

Abstract

To provide a toner which is excellent in low temperature fixability and hot offset resistance, and enlarges a fixation temperature width.SOLUTION: A toner contains an amorphous polyester-based resin, a crystalline polyester resin, and a wax, wherein the amorphous polyester-based resin contains an amine-modified polyester resin (A) obtained by condensing an amine compound into a polycondensate of an alcohol component and a carboxylic acid component, the alcohol component contains 60 mol% or more of aliphatic diol, and the acid value of the crystalline polyester resin is 20 mgKOH / g or more.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a toner used for developing a latent image formed in an electrophotographic method, an electrostatic recording method, an electrostatic printing method or the like. [Background technology]

[0002] In the field of electrophotography, with the development of electrophotographic systems, there is a demand for the development of toners that can handle higher image quality and faster speeds. In general, by lowering the minimum fixing temperature and raising the temperature at which high-temperature offset occurs, the fixing temperature range can be expanded, and the demands for energy saving and faster fixing can be met.

[0003] Patent Document 1 describes a binder resin for toner that contains a resin (N) having an amino group, an amorphous resin (A) other than the resin (N), and a crystalline resin (C) other than the resin (N). Patent Document 2 describes a binder resin composition for toner, which contains a resin composition (CP) obtained by condensing a crystalline resin (C) having an acid group with a polyalkyleneimine, and an amorphous resin (A). Patent Document 3 describes a toner for developing electrostatic images, which includes a colorant, a resin composition obtained by condensing an amorphous polyester resin having an acid group with an amine compound, and one or more ester compositions selected from an ester composition (CI) containing a condensate of a carboxylic acid component containing 20 mol % or more of an aliphatic monocarboxylic acid compound and an alcohol component containing 90 mol % or more of a divalent or higher aliphatic alcohol, and an ester composition (CII) containing a condensate of an alcohol component containing 20 mol % or more of an aliphatic monoalcohol and a carboxylic acid component containing 90 mol % or more of a divalent or higher aliphatic carboxylic acid compound. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2020-85932 A [Patent Document 2] JP 2020-24360 A [Patent Document 3] Patent Publication No. 2021-47403 Summary of the Invention [Problem to be solved by the invention]

[0005] Although the toners described in Patent Documents 1 to 3 have excellent low-temperature fixing properties, there is room for improvement in hot offset resistance. The present invention relates to a toner having excellent low-temperature fixing property and hot offset resistance and having an expanded fixing temperature range. [Means for solving the problem]

[0006] The present inventors have found that the above problems can be solved by a toner containing an amorphous polyester resin containing an amine-modified polyester resin (A), a crystalline polyester resin having an acid value of 20 mgKOH / g or more, and a wax.

[0007] That is, the present invention relates to the following [1]. [1] A toner comprising an amorphous polyester resin, a crystalline polyester resin, and a wax, The amorphous polyester resin contains an amine-modified polyester resin (A) obtained by condensing an amine compound with a polycondensate of an alcohol component and a carboxylic acid component, The alcohol component contains 60 mol % or more of an aliphatic diol, The toner, wherein the crystalline polyester resin has an acid value of 20 mgKOH / g or more. Effect of the Invention

[0008] According to the present invention, it is possible to provide a toner which is excellent in low-temperature fixing property and hot offset resistance and has a wide fixing temperature range. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] [toner] The toner of the present invention is a toner containing an amorphous polyester resin, a crystalline polyester resin, and a wax, the amorphous polyester resin containing an amine-modified polyester resin (A) obtained by condensing an amine compound with a polycondensate of an alcohol component and a carboxylic acid component, the alcohol component containing 60 mol % or more of an aliphatic diol, and the crystalline polyester resin having an acid value of 20 mgKOH / g or more. By using the above-mentioned composition, it is possible to obtain a toner having excellent low-temperature fixing property and hot offset resistance and having a wide fixing temperature range. Although the reason for this is not clear, it is believed to be as follows.

[0010] It is known that a crystalline polyester resin is finely dispersed in an amorphous resin, which is a binder resin of a toner, and thereby makes it easier to plasticize the amorphous resin when fixing the toner, thereby improving the low-temperature fixing property of the toner. However, when the amorphous resin is an amorphous polyester resin containing an aliphatic alcohol as the main component of the alcohol component, the amorphous polyester resin has a higher hydrophilicity than an amorphous polyester resin containing an aromatic alcohol as the main component of the alcohol component, and therefore has a lower affinity with the hydrophobic crystalline polyester resin, which is a problem in that it is difficult to finely disperse the crystalline polyester resin in the toner. The toner of the present invention contains, as a binder resin, a crystalline polyester resin having an acid group, and an amine-modified polyester resin (A) in which an amine compound is condensed with an amorphous polyester resin having an aliphatic alcohol as the main alcohol component. Therefore, it is believed that the acid group of the crystalline polyester resin and the amino group of the amine-modified polyester resin (A) form an acid-base interaction, so that the crystalline polyester resin can be finely dispersed in the amorphous polyester resin, and the low-temperature fixing property of the toner is improved. In addition, it is believed that the fine dispersion of the crystalline polyester resin in the amorphous polyester resin makes it possible to finely disperse wax, which is hydrophobic like the crystalline polyester resin, in the amorphous polyester resin, and the finely dispersed wax bleeds out more uniformly on the toner surface when the toner is fixed, thereby improving the hot offset resistance. It is believed that the improvement in low-temperature fixing property and hot offset resistance results in an expansion of the fixing temperature range.

[0011] The definitions of various terms used in this specification are given below. Whether a resin is crystalline or amorphous is determined by the crystallinity index. The crystallinity index is defined as the ratio of the softening point of the resin to the endothermic maximum peak temperature (softening point (°C) / endothermic maximum peak temperature (°C)) in the measurement method described in the Examples below. A crystalline resin is a resin with a crystallinity index of 0.6 or more and 1.4 or less. An amorphous resin is a resin in which no endothermic peak is observed, or in which the crystallinity index is greater than 1.4 or less than 0.6 when an endothermic peak is observed. The crystallinity index can be appropriately adjusted depending on the type and ratio of raw material monomers, as well as production conditions such as reaction temperature, reaction time, and cooling rate. The endothermic maximum peak temperature refers to the temperature of the endothermic peak with the largest peak area among the endothermic peaks observed under the conditions of the measurement method described in the Examples. In the specification, the carboxylic acid component of the polyester resin includes not only the exemplified compounds, but also anhydrides that decompose during the reaction to produce an acid, and alkyl esters of each carboxylic acid (alkyl groups having 1 to 3 carbon atoms). In the present specification, the term "binder resin composition" refers to a resin component contained in a toner that contains a condensate.

[0012] The toner of the present invention contains an amorphous polyester resin, a crystalline polyester resin, and a wax. The toner contains, for example, toner base particles containing an amorphous polyester resin, a crystalline polyester resin, and a wax, and an external additive.

[0013] [Amorphous polyester resin] The amorphous polyester resin contains an amine-modified polyester resin (A) in which an amine compound is condensed with a polycondensate of an alcohol component and a carboxylic acid component.

[0014] <Amine-modified polyester resin (A)> The amine-modified polyester resin (A) is an amine-modified polyester resin in which an amine compound is condensed with a polyester resin, which is a polycondensation product of an alcohol component and a carboxylic acid component, and the alcohol component constituting the polyester resin contains 60 mol % or more of an aliphatic diol.

[0015] (Alcohol content) Examples of the aliphatic diol contained in the alcohol component include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 2,3-butanediol, 1,4-butanediol, 1,2-pentanediol, 1,4-pentanediol, 1,5-pentanediol, 2,4-pentanediol, 1,2-hexanediol, 1,5-hexanediol, 2,5-hexanediol, 1,6-hexanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,12-dodecanediol, 1,14-tetradecanediol, 1,16-hexadecanediol, 3,3-dimethyl-1,2-butanediol, and neopentyl glycol (2,2-dimethyl-1,3-propanediol). Among these, the alcohol component preferably contains an aliphatic diol having 2 to 6 carbon atoms, more preferably contains one or more selected from ethylene glycol and 1,2-propanediol, and even more preferably contains 1,2-propanediol. The alcohol component may contain other alcohols in addition to the aliphatic diols, as long as the effects of the present invention are not impaired. Examples of other alcohols include diols such as aromatic diols and alicyclic diols, and polyhydric alcohols having three or more hydric groups.

[0016] Examples of the aromatic diol include alkylene oxide adducts of aromatic diols. Examples of the alicyclic diol include cyclohexanedimethanol, hydrogenated bisphenol A, and adducts of hydrogenated bisphenol A with alkylene oxides having 2 to 4 carbon atoms (average number of moles added: 2 to 12). Examples of the trihydric or higher polyhydric alcohol include glycerin, pentaerythritol, trimethylolpropane, sorbitol, and sorbitan. The other alcohols may be used alone or in combination of two or more.

[0017] From the viewpoint of improving the low-temperature fixing property and hot offset resistance of the toner, the content of the aliphatic diol in the alcohol component is 60 mol % or more, preferably 80 mol % or more, more preferably 90 mol % or more, and preferably 100 mol % or less, and even more preferably 100 mol %.

[0018] (Carboxylic acid component) Examples of the carboxylic acid component include dicarboxylic acids and polycarboxylic acids having three or more carboxylic acids.

[0019] Dicarboxylic acids include, for example, aromatic dicarboxylic acids, aliphatic dicarboxylic acids, and alicyclic dicarboxylic acids. The dicarboxylic acid preferably has 2 or more, more preferably 3 or more, and preferably has 30 or less, more preferably 20 or less. Examples of aromatic dicarboxylic acids include phthalic acid, terephthalic acid, and isophthalic acid. Among these, terephthalic acid is preferred. Examples of aliphatic dicarboxylic acids include oxalic acid, malonic acid, maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, succinic acid, pentanedioic acid, adipic acid, sebacic acid, dodecanedioic acid, azelaic acid, and succinic acid substituted with an aliphatic hydrocarbon group having from 1 to 20 carbon atoms. Examples of succinic acid substituted with an aliphatic hydrocarbon group having 1 to 20 carbon atoms include n-dodecenylsuccinic acid, isododecenylsuccinic acid, n-dodecylsuccinic acid, isododecylsuccinic acid, n-octenylsuccinic acid, n-octylsuccinic acid, isooctylsuccinic acid, and isooctylsuccinic acid. An example of the alicyclic dicarboxylic acid is cyclohexanedicarboxylic acid.

[0020] Examples of trivalent or higher polyvalent carboxylic acids include 1,2,4-benzenetricarboxylic acid (trimellitic acid), 2,5,7-naphthalenetricarboxylic acid, and pyromellitic acid. Among these, trimellitic acid is preferred.

[0021] From the viewpoint of improving the low-temperature fixing property and hot offset resistance of the toner, the amount of the aromatic dicarboxylic acid in the carboxylic acid component is preferably 75 mol % or more, more preferably 80 mol % or more, even more preferably 85 mol % or more, and is 100 mol % or less, preferably 95 mol % or less, more preferably 93 mol % or less, even more preferably 90 mol % or less. From the viewpoint of improving the low-temperature fixing property and hot offset resistance of the toner, the amount of the trivalent or higher polyvalent carboxylic acid in the carboxylic acid component is preferably 5 mol % or more, more preferably 7 mol % or more, even more preferably 10 mol % or more, and is preferably 25 mol % or less, more preferably 20 mol % or less, even more preferably 15 mol % or less.

[0022] The equivalent ratio of the carboxyl group (COOH group) of the carboxylic acid component to the hydroxyl group (OH group) of the alcohol component [COOH group / OH group] is preferably 0.7 or more, more preferably 0.8 or more, and is preferably 1.3 or less, more preferably 1.2 or less.

[0023] (Amine compounds) Examples of the amine compound include tertiary amines having a hydroxyalkyl group, and tertiary amines having a carboxyalkyl group. Examples of tertiary amines having a hydroxyalkyl group include triethanolamine, triisopropanolamine, N-methyldiethanolamine, N-ethyldiethanolamine, 2-dimethylaminoethanol, 2-diethylaminoethanol, 2-dipropylaminoethanol, 2-diisopropylaminoethanol, 2-dibutylaminoethanol, 3-dimethylamino-1-propanol, 3-diethylamino-1-propanol, 3-dipropylamino-1-propanol, 3-diisopropylamino-1-propanol, 3-dibutylamino-1-propanol, 4-dimethylamino-1-butanol, 4-diethylamino-1-butanol, 4-dipropylamino-1-butanol, 4-diisopropylamino-1-butanol, 4-dibutylamino-1-butanol, 3-dimethylamino-1,2-propanediol, 3-diethylamino-1,2-propanediol, 3-dipropylamino-1,2-propanediol, and 3-diisopropylamino-1,2-propanediol. Examples of tertiary amines having a carboxyalkyl group include N,N-dimethylglycine, N,N-diethylglycine, N,N-dipropylglycine, N,N-diisopropylglycine, N,N-dibutylglycine, N-methyliminodiacetic acid, N-ethyliminodiacetic acid, N-propyliminodiacetic acid, N-isopropyliminodiacetic acid, N-butyliminodiacetic acid, 1-pyrrolidineacetic acid, 1-piperidineacetic acid, nitrilotriacetic acid, N-(2-carboxyethyl)iminodiacetic acid, 3-dimethylaminopropionic acid, 3-diethylaminopropionic acid, and 3-methylaminopropionic acid. pionic acid, 3-dipropylaminopropionic acid, 3-diisopropylaminopropionic acid, 3-dibutylaminopropionic acid, N-methyl-3,3'-iminodipropionic acid, N-ethyl-3,3'-iminodipropionic acid, N-propyl-3,3'-iminodipropionic acid, N-isopropyl-3,3'-iminodipropionic acid, N-butyl-3,3'-iminodipropionic acid, 3-(1-pyrrolidine)propionic acid, 3-(1-piperidine)propionic acid, 3,3',3''-nitrilotripropionic acid, and the like. Among these, the amine compound is preferably a tertiary amine having a hydroxyalkyl group for introduction into the amorphous polyester resin, more preferably at least one selected from the group consisting of N-methyldiethanolamine, 2-diethylaminoethanol, and 2-dibutylaminoethanol, and even more preferably N-methyldiethanolamine, 2-diethylaminoethanol, or 2-dibutylaminoethanol.

[0024] The content of the amine compound-derived structural unit in the amine-modified polyester resin (A) is preferably 0.5% by mass or more, more preferably 1.0% by mass or more, even more preferably 1.5% by mass or more, and is preferably 10% by mass or less, more preferably 8% by mass or less, even more preferably 5% by mass or less, from the viewpoint of improving the low-temperature fixing property and hot offset resistance of the toner. The mass of the amine-modified polyester resin (A) is based on the mass excluding the mass of water generated by the reaction.

[0025] <Production method of amine-modified polyester resin (A)> The amine-modified polyester resin (A) can be produced, for example, by a method including a step A of polycondensing an alcohol component and a carboxylic acid component to obtain an amorphous polyester resin, and a step B of condensing an acid group of the amorphous polyester resin with a hydroxyl group of an amine compound. Moreover, instead of step A, or in addition to the amorphous polyester resin obtained in step A, a separately prepared amorphous polyester resin may be used.

[0026] In step A, if necessary, polycondensation may be performed using an esterification catalyst such as tin(II) di(2-ethylhexanoate), dibutyltin oxide, titanium diisopropoxybis(triethanolaminate) in an amount of 0.01 part by mass or more and 5 parts by mass or less per 100 parts by mass of the total amount of the alcohol component and the carboxylic acid component, and an esterification promoter such as gallic acid (same as 3,4,5-trihydroxybenzoic acid) in an amount of 0.001 part by mass or more and 0.5 part by mass or less per 100 parts by mass of the total amount of the alcohol component and the carboxylic acid component. When a monomer having an unsaturated bond such as fumaric acid is used in polycondensation, a radical polymerization inhibitor may be used, if necessary, in an amount of preferably 0.001 to 0.5 parts by mass per 100 parts by mass of the total amount of the alcohol component and the carboxylic acid component. An example of the radical polymerization inhibitor is 4-tert-butylcatechol. The temperature of the polycondensation reaction is preferably 120° C. or higher, more preferably 140° C. or higher, and preferably 250° C. or lower, more preferably 240° C. or lower. The polycondensation may be carried out in an inert gas atmosphere.

[0027] In step B, the condensation of the acid group of the amorphous polyester resin with the amine compound can be carried out by heating and removing water produced by the dehydration reaction from the system by reducing pressure or the like. The temperature of the condensation reaction is preferably 120° C. or higher, more preferably 140° C. or higher, and preferably 250° C. or lower, more preferably 230° C. or lower, and further preferably 210° C. or lower. The condensation may be carried out in an inert gas atmosphere.

[0028] In the production of the amine-modified polyester resin (A), the amount of the amine compound is preferably 0.5 parts by mass or more, more preferably 1.0 parts by mass or more, even more preferably 1.5 parts by mass or more, and preferably 10 parts by mass or less, more preferably 8 parts by mass or less, even more preferably 5 parts by mass or less, based on 100 parts by mass of the raw materials for the amorphous polyester resin, from the viewpoint of improving the low-temperature fixing property and hot offset resistance of the toner. The total amount of the raw materials for the amorphous polyester resin means the total amount of the alcohol component and the carboxylic acid component. In addition, when a separately prepared amorphous polyester resin is used, the total amount of the alcohol component, the carboxylic acid component, and the amorphous polyester resin is used.

[0029] The method may include a step of steaming a reaction mixture containing the amine-modified polyester resin (A) after obtaining the amine-modified polyester resin (A). By steaming the reaction mixture, unreacted amine compounds contained in the condensate can be efficiently removed. Steaming may be carried out by introducing water vapor into the reaction system, or by generating water vapor in the reaction system by dripping ion-exchanged water into the reaction system. From the viewpoint of ease of operation, it is preferable to generate water vapor in the reaction system by dripping ion-exchanged water into the reaction system. In order to efficiently separate the amine compound from the reaction mixture, the supply amount of water vapor or ion-exchanged water is preferably 1 part by mass or more and 10 parts by mass or less with respect to 100 parts by mass of the total amount of the amine-modified polyester resin (A).

[0030] <Physical properties of amine-modified polyester resin (A)> The glass transition temperature of the amine-modified polyester resin (A) is preferably 50° C. or higher, more preferably 55° C. or higher, and even more preferably 60° C. or higher, and from the viewpoint of further improving low-temperature fixability, is preferably 90° C. or lower, more preferably 85° C. or lower, and even more preferably 80° C. or lower. The softening point of the amine-modified polyester resin (A) is preferably 90°C or higher, more preferably 100°C or higher, and even more preferably 105°C or higher. From the viewpoint of further improving low-temperature fixability, it is preferably 150°C or lower, more preferably 140°C or lower, and even more preferably 130°C or lower.

[0031] The acid value of the amine-modified polyester resin (A) is preferably 1 mgKOH / g or more, more preferably 5 mgKOH / g or more, and even more preferably 10 mgKOH / g or more, and from the viewpoint of further improving low-temperature fixability, is preferably 50 mgKOH / g or less, more preferably 40 mgKOH / g or less, and even more preferably 35 mgKOH / g or less.

[0032] The glass transition temperature, softening point, and acid value of the amine-modified polyester resin (A) can be appropriately adjusted by the types and amounts of raw material monomers used, as well as production conditions such as reaction temperature, reaction time, and cooling rate, and these values ​​can be determined by the methods described in the examples. When two or more kinds of amine-modified polyester resins (A) are used in combination, the glass transition temperature, softening point and acid value of the mixture obtained are preferably within the above-mentioned ranges.

[0033] From the viewpoint of improving the low-temperature fixing property and hot offset resistance of the toner, the content of the amine-modified polyester resin (A) in the toner is preferably 50% by mass or more, more preferably 55% by mass or more, even more preferably 60% by mass or more, and more preferably 85% by mass or less, even more preferably 80% by mass or less.

[0034] The amorphous polyester resin may contain an amorphous polyester resin in addition to the amine-modified polyester resin (A). In order to improve the low-temperature fixing property and hot offset resistance of the toner, such amorphous polyester resins include amorphous polyester resins and modified polyester resins having a higher softening point than the amine-modified polyester resin (A). Modified polyester resins include, for example, urethane-modified polyester resins, epoxy-modified polyester resins, and composite resins containing polyester resin segments and addition polymerization resin segments.

[0035] [Crystalline polyester resin] The crystalline polyester resin is, for example, a polycondensate of an alcohol component and a carboxylic acid component. From the viewpoint of improving the low-temperature fixing property and hot offset resistance of the toner, the softening point of the crystalline polyester resin is preferably lower than the softening point of the amine-modified polyester resin (A).

[0036] The alcohol component is preferably an α,ω-aliphatic diol. The α,ω-aliphatic diol has preferably 2 or more, more preferably 4 or more, even more preferably 6 or more, and preferably 16 or less, more preferably 14 or less, even more preferably 12 or less. Examples of α,ω-aliphatic diols include ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, 1,12-dodecanediol, 1,13-tridecanediol, and 1,14-tetradecanediol. Among these, 1,4-butanediol, 1,6-hexanediol, 1,8-octanediol, 1,10-decanediol, and 1,12-dodecanediol are preferred, and 1,6-hexanediol is more preferred.

[0037] The amount of the α,ω-aliphatic diol in the alcohol component is preferably 80 mol % or more, more preferably 90 mol % or more, even more preferably 95 mol % or more, and is 100 mol % or less, even more preferably 100 mol %.

[0038] The alcohol component may contain other alcohol components different from the α,ω-aliphatic diol. Examples of the other alcohol components include aliphatic diols other than α,ω-aliphatic diols, such as 1,2-propanediol and neopentyl glycol; aromatic diols, such as alkylene oxide adducts of bisphenol A; and trihydric or higher alcohols, such as glycerin, pentaerythritol, and trimethylolpropane. These alcohol components may be used alone or in combination.

[0039] The carboxylic acid component is preferably an aliphatic dicarboxylic acid, more preferably a straight-chain aliphatic dicarboxylic acid. The aliphatic dicarboxylic acid preferably has 4 or more carbon atoms and preferably has 14 or less, more preferably 12 or less carbon atoms. Examples of the aliphatic dicarboxylic acid include fumaric acid, sebacic acid, dodecanedioic acid, and tetradecanedioic acid. Among these, fumaric acid, sebacic acid, and tetradecanedioic acid are preferred, and sebacic acid is more preferred. These carboxylic acid components may be used alone or in combination.

[0040] The amount of the aliphatic dicarboxylic acid in the carboxylic acid component is preferably 80 mol % or more, more preferably 90 mol % or more, even more preferably 95 mol % or more, and is 100 mol % or less, even more preferably 100 mol %.

[0041] The carboxylic acid component may contain other carboxylic acid components different from the aliphatic dicarboxylic acid. Examples of other carboxylic acid components include aromatic dicarboxylic acids such as terephthalic acid and isophthalic acid, and polyvalent carboxylic acids having three or more carboxylic acids. These carboxylic acid components may be used alone or in combination.

[0042] The equivalent ratio of the carboxyl groups of the carboxylic acid component to the hydroxyl groups of the alcohol component [COOH groups / OH groups] is preferably 0.7 or more, more preferably 0.8 or more, and is preferably 1.3 or less, more preferably 1.2 or less.

[0043] The crystalline polyester resin may be produced, for example, by a process of polycondensing an alcohol component and a carboxylic acid component. The step of polycondensing the alcohol component and the carboxylic acid component is the same as step A described in the production method of the amine-modified polyester resin (A), and the preferred ranges are also the same.

[0044] <Physical properties of crystalline polyester resin> From the viewpoint of the storage stability of the toner, the softening point of the crystalline polyester resin is preferably 50° C. or higher, more preferably 60° C. or higher, and even more preferably 65° C. or higher, and from the viewpoint of further improving the low-temperature fixing ability, it is preferably 90° C. or lower, more preferably 85° C. or lower, and even more preferably 80° C. or lower. From the viewpoint of the storage stability of the toner, the melting point of the crystalline polyester resin is preferably 40° C. or higher, more preferably 50° C. or higher, and even more preferably 60° C. or higher, and from the viewpoint of further improving low-temperature fixing ability, it is preferably 85° C. or lower, more preferably 80° C. or lower, and even more preferably 75° C. or lower.

[0045] From the viewpoint of improving the low-temperature fixing property and hot offset resistance of the toner, the acid value of the crystalline polyester resin is 20 mgKOH / g or more, more preferably 23 mgKOH / g or more, even more preferably 25 mgKOH / g or more, and is preferably 50 mgKOH / g or less, more preferably 40 mgKOH / g or less, even more preferably 35 mgKOH / g or less.

[0046] The softening point and melting point of the crystalline polyester resin can be appropriately adjusted by the type and amount of raw material monomers, as well as production conditions such as reaction temperature, reaction time, cooling rate, etc., and are determined by the method described in the Examples below. When two or more crystalline polyester resins are used in combination, it is preferable that the softening point and melting point values ​​obtained as a mixture of these are each within the above ranges.

[0047] From the viewpoint of improving the low-temperature fixing property and hot offset resistance of the toner, the content of the crystalline polyester resin in the toner is preferably 3% by mass or more, more preferably 5% by mass or more, even more preferably 7% by mass or more, and is preferably 20% by mass or less, more preferably 18% by mass or less, even more preferably 15% by mass or less.

[0048] From the viewpoint of improving the low-temperature fixing property and hot offset resistance of the toner, the mass ratio of the crystalline polyester resin to the amorphous polyester resin (crystalline polyester resin / amorphous polyester resin) is preferably 0.03 or more, more preferably 0.05 or more, even more preferably 0.08 or more, and is preferably 0.4 or less, more preferably 0.3 or less, even more preferably 0.2 or less.

[0049] From the viewpoint of improving the low-temperature fixing property and hot offset resistance of the toner, the mass ratio of the crystalline polyester resin to the amine-modified polyester resin (A) (crystalline polyester resin / amine-modified polyester resin (A)) is preferably 0.03 or more, more preferably 0.05 or more, even more preferably 0.08 or more, and is preferably 0.4 or less, more preferably 0.3 or less, even more preferably 0.2 or less.

[0050] From the viewpoint of improving the low-temperature fixing property and hot offset resistance of the toner, the content of the amorphous polyester resin and the crystalline polyester resin in the toner is preferably 60% by mass or more, more preferably 65% ​​by mass or more, even more preferably 70% by mass or more, and is preferably 95% by mass or less, more preferably 90% by mass or less, even more preferably 85% by mass or less.

[0051] 〔wax〕 The toner of the present invention contains a wax in addition to the amorphous polyester resin and the crystalline polyester resin.

[0052] Examples of waxes include polypropylene wax, polyethylene wax, polypropylene-polyethylene copolymer wax, hydrocarbon waxes such as microcrystalline wax, paraffin wax, Fischer-Tropsch wax, and oxides thereof, ester waxes such as carnauba wax, montan wax, and deacidified waxes thereof, and fatty acid ester wax, fatty acid amides, fatty acids, higher alcohols, and fatty acid metal salts. These may be used alone or in combination of two or more.

[0053] From the viewpoint of improving hot offset resistance, the melting point of the wax is preferably 60°C or higher, more preferably 70°C or higher, and preferably 160°C or lower, more preferably 140°C or lower, even more preferably 120°C or lower, and even more preferably 100°C or lower. From the viewpoint of improving hot offset resistance, the wax content in the toner is preferably 1% by mass or more, more preferably 2% by mass or more, even more preferably 3% by mass or more, and is preferably 10% by mass or less, more preferably 7% by mass or less, even more preferably 5% by mass or less.

[0054] [Coloring Agent] The toner of the present invention may contain a colorant. As the colorant, any of dyes, pigments, etc. that are used as colorants for toners can be used. Examples of colorants include carbon black, phthalocyanine blue (e.g., pigment blue 15:3), permanent brown FG, brilliant fast scarlet, pigment green B, rhodamine-B base, solvent red 49, solvent red 146, solvent blue 35, quinacridone, carmine 6B, and disazo yellow. The toner may be either a black toner or a color toner other than black. The content of the colorant in the toner is preferably 1% by mass or more, more preferably 3% by mass or more, and preferably 10% by mass or less, more preferably 8% by mass or less.

[0055] [Charge control agent] The toner of the present invention may contain a charge control agent. The charge control agent may be either a positively chargeable charge control agent or a negatively chargeable charge control agent. Among these, a positively chargeable charge control agent is preferred. Examples of the positively charged charge control agent include nigrosine dyes such as "Nigrosine Base EX", "Oil Black BS", "Oil Black SO", "Bontron (registered trademark) N-01", "Bontron (registered trademark) N-04", "Bontron (registered trademark) N-07", "Bontron (registered trademark) N-09", and "Bontron (registered trademark) N-11" (all manufactured by Orient Chemical Industry Co., Ltd.); triphenylmethane dyes containing a tertiary amine as a side chain, quaternary ammonium salt compounds such as "Bontron (registered trademark) P-51" (manufactured by Orient Chemical Industry Co., Ltd.), cetyltrimethylammonium bromide, and "COPY CHARGE PX Examples of such resins include "VP435" (manufactured by Clariant), etc.; polyamine resins, such as "AFP-B" (manufactured by Orient Chemical Industry Co., Ltd.); imidazole derivatives, such as "PLZ-2001" and "PLZ-8001" (both manufactured by Shikoku Chemical Industry Co., Ltd.); and styrene-acrylic resins, such as "FCA-701PT" and "FCA-201-PS" (manufactured by Fujikura Chemical Industry Co., Ltd.).

[0056] Examples of the negatively chargeable charge control agent include metal-containing azo dyes such as "Varifast (registered trademark) Black 3804", "Bontron (registered trademark) S-31", "Bontron (registered trademark) S-32", "Bontron (registered trademark) S-34", "Bontron (registered trademark) S-36" (all manufactured by Orient Chemical Industry Co., Ltd.), "Aizen Spiron Black TRH", "T-77" (manufactured by Hodogaya Chemical Industry Co., Ltd.), etc.; metal compounds of benzilic acid compounds such as "LR-147" and "LR-297" (all manufactured by Nippon Carlit Co., Ltd.); metal compounds of salicylic acid compounds such as "Bontron (registered trademark) E-81", "Bontron (registered trademark) E-84", "Bontron (registered trademark) E-88", "Bontron (registered trademark) E-304" (all manufactured by Orient Chemical Industry Co., Ltd.), "TN-105" (manufactured by Hodogaya Chemical Industry Co., Ltd.), etc.; copper phthalocyanine dyes; and quaternary ammonium salts such as "COPY CHARGE PX VP434" (Clariant), nitroimidazole derivatives, etc.; organometallic compounds, etc. These charge control agents may be used alone or in combination of two or more kinds.

[0057] The content of the charge control agent in the toner is preferably 1% by mass or more, more preferably 5% by mass or more, even more preferably 8% by mass or more, and preferably 25% by mass or less, more preferably 20% by mass or less, even more preferably 15% by mass or less.

[0058] [Other additives] The toner may further contain, as other additives, additives such as magnetic powder, a flowability improver, a conductivity adjuster, a reinforcing filler such as a fibrous substance, an antioxidant, an antiaging agent, and a cleaning property improver, as appropriate.

[0059] In the toner of the present invention, the content of the toner base particles is preferably 80% by mass or more, more preferably 90% by mass or more, even more preferably 95% by mass or more, and is 100% by mass or less, preferably 99% by mass or less.

[0060] The volume median particle size of the toner base particles (D 50) is preferably 2 μm or more, more preferably 3 μm or more, even more preferably 4 μm or more, and is preferably 15 μm or less, more preferably 10 μm or less. 50 ) means the particle size at which the cumulative volume frequency calculated by volume fraction is 50% calculated from the smallest particle size.

[0061] [External additives] The toner of the present invention may further contain an external additive in order to improve fluidity. Examples of the external additive include inorganic material particles such as silica, alumina, titania, zirconia, tin oxide, and zinc oxide, and organic particles such as resin particles such as melamine resin particles and polytetrafluoroethylene resin particles. These may be used alone or in combination. Among these external additives, silica is preferred, and hydrophobic silica treated with a hydrophobic treatment agent is more preferred.

[0062] Examples of hydrophobic treatment agents include hexamethyldisilazane (HMDS), dimethyldichlorosilane (DMDS), silicone oil, octyltriethoxysilane (OTES), and methyltriethoxysilane. Among these, hexamethyldisilazane is preferred.

[0063] When the toner base particles are surface-treated using an external additive, the content of the external additive in the toner of the present invention is, from the viewpoint of the chargeability and flowability of the toner, preferably 0.5 parts by mass or more, more preferably 0.8 parts by mass or more, even more preferably 1 part by mass or more, and preferably 10 parts by mass or less, more preferably 5 parts by mass or less, even more preferably 4 parts by mass or less, relative to 100 parts by mass of the toner base particles.

[0064] [Toner manufacturing method] The toner of the present invention may be a toner obtained by any of the known methods such as a melt kneading method, an emulsion phase inversion method, a suspension polymerization method, an emulsion aggregation method, etc., but from the viewpoints of productivity and dispersibility of the colorant, a pulverized toner obtained by a melt kneading method is preferred. In the melt kneading method, amorphous polyester resin, crystalline polyester resin, and wax, and if necessary, property improvers such as colorants, are uniformly dispersed, and then melt kneaded, cooled, pulverized, and classified by a known method to obtain a volume median particle size (D 50 ) Toner having a particle size of 2 μm or more and 15 μm or less can be obtained.

[0065] The toner of the present invention is used for developing latent images formed in electrophotography, electrostatic recording, electrostatic printing, etc. The toner can be used as a one-component developer, or mixed with a carrier to form a two-component developer. EXAMPLES

[0066] The present invention will be described in detail below with reference to examples, but the present invention is not limited to these examples. Physical properties of resins and the like were measured by the following methods.

[0067] [measurement] [Resin softening point, crystallinity index, melting point, glass transition temperature] (1) Softening point Using a flow tester "CFT-500D" (Shimadzu Corporation), 1 g of sample was heated at a temperature increase rate of 6°C / min, while applying a load of 1.96 MPa with the plunger, and extruding the sample from a nozzle with a diameter of 1 mm and a length of 1 mm. The plunger descent amount of the flow tester was plotted against the temperature, and the temperature at which half of the sample flowed out was taken as the softening point.

[0068] (2) Crystallinity index Using a differential scanning calorimeter "Q100" (manufactured by TA Instruments Japan Co., Ltd.), 0.02 g of sample was weighed into an aluminum pan and cooled to 0°C at a rate of 10°C / min. The sample was then left to stand for 1 minute, after which it was heated to 180°C at a rate of 10°C / min and the calorific value was measured. The temperature of the peak with the largest peak area among the observed endothermic peaks was taken as the endothermic maximum peak temperature (1), and the crystallinity index was calculated by (softening point (°C)) / (endothermic maximum peak temperature (1) (°C)).

[0069] (3) Melting point and glass transition temperature Using a differential scanning calorimeter "Q100" (manufactured by TA Instruments Japan Co., Ltd.), 0.02 g of the sample was weighed into an aluminum pan, heated to 200°C, and cooled from that temperature to 0°C at a rate of 10°C / min. The sample was then heated at a rate of 10°C / min, and the calorific value was measured. Among the endothermic peaks observed, the temperature of the peak with the largest peak area was taken as the maximum endothermic peak temperature (2). In the case of a crystalline resin, this peak temperature was taken as the melting point. In the case of an amorphous resin, when a peak was observed, the temperature of the peak was taken as the glass transition temperature. When no peak was observed but a step was observed, the temperature at the intersection of the tangent showing the maximum slope of the curve at the step and an extension of the baseline on the low temperature side of the step was taken as the glass transition temperature.

[0070] [Acid value of resin] Measurements were performed in accordance with JIS K0070: 1992, except that the measurement solvent was a mixed solvent of acetone and toluene (acetone:toluene=1:1 (volume ratio)).

[0071] [Volume median particle diameter of toner base particles D 50 〕 Volume median particle size D of toner base particles 50 was measured as follows: Measuring instrument: "Coulter Multisizer (registered trademark) III" (manufactured by Beckman Coulter, Inc.) Aperture diameter: 50μm Analysis software: "Multisizer (registered trademark) III version 3.51" (Beckman Coulter, Inc.) Electrolyte: "Isoton (registered trademark) II" (manufactured by Beckman Coulter, Inc.) Dispersion liquid: Polyoxyethylene lauryl ether "EMULGEN (registered trademark) 109P" (manufactured by Kao Corporation, HLB: 13.6) was dissolved in the electrolyte to obtain a dispersion liquid with a concentration of 5% by mass. Dispersion conditions: 10 mg of a toner measurement sample was added to 5 mL of the dispersion liquid, and dispersed for 1 minute using an ultrasonic disperser. Thereafter, 25 mL of electrolyte was added, and the mixture was further dispersed for 1 minute using an ultrasonic disperser to prepare a sample dispersion liquid. Measurement conditions: The sample dispersion is added to 100 mL of the electrolyte to adjust the concentration so that the particle size of 30,000 particles can be measured in 20 seconds. Then, 30,000 particles are measured and the volume median particle size D is calculated from the particle size distribution. 50 asked for.

[0072] [Resin manufacturing] Production example A1 (resin A-1) 2699.0 g of 1,2-propanediol was placed in a 10-liter four-neck flask equipped with a dehydration tube equipped with a nitrogen inlet tube, a rectification column through which hot water of 95 ° C. was passed, a stirrer, and a thermocouple, and the mixture was heated to 100 ° C., after which 4491.6 g of terephthalic acid and 39.2 g of di(2-ethylhexanoate)tin(II) were added, the mixture was heated to 180 ° C., and reacted at 180 ° C. for 1 hour. The mixture was then heated stepwise to 235 ° C. at 5 ° C. / h, and reacted at 235 ° C. for 1 hour. The mixture was then cooled to 160 ° C., and 138.4 g of 2-diethylaminoethanol (manufactured by Nippon Nyukazai Co., Ltd., trade name: Amino Alcohol 2A) was added, the mixture was heated to 160 ° C., and reacted for 1 hour. The mixture was then heated stepwise to 210 ° C. at 10 ° C. / h, and 649.4 g of trimellitic anhydride was added, and reacted for 1 hour. Thereafter, the pressure in the flask was reduced, and the reaction was carried out under reduced pressure at 8 kPa until the desired softening point was reached, thereby obtaining Resin A-1 as an amine-modified polyester resin (A). The physical properties are shown in Table 1.

[0073] Manufacturing Examples A2 and A3 (Resins A-2 and A-3) Resins A-2 and A-3 were obtained as amine-modified polyester resins (A) in the same manner as in Production Example A1, except that 2-diethylaminoethanol was replaced with N-methyldiethanolamine (manufactured by Nippon Nyukazai Co., Ltd., product name: Amino Alcohol MDA) or 2-dibutylaminoethanol (manufactured by Nippon Nyukazai Co., Ltd., product name: Amino Alcohol 2B). The physical properties are shown in Table 1.

[0074] Manufacturing example A4 (resin A-4) 2283.4g of 1,2-propanediol was placed in a 10-liter four-neck flask equipped with a dehydration tube equipped with a nitrogen inlet tube, a rectification column flowing with hot water at 95°C, a stirrer and a thermocouple, and the mixture was heated to 100°C, after which 3520.6g of terephthalic acid, 1357.3g of recycled PET (manufactured by Utsumi Recycle Systems Co., Ltd., product name: UK-31), and 39.2g of di(2-ethylhexanoate)tin(II) were added, the mixture was heated to 180°C, and reacted at 180°C for 1 hour. The mixture was then heated stepwise to 235°C at 5°C / h, and reacted at 235°C for 1 hour. The mixture was then cooled to 160°C, and 142.6g of N-methyldiethanolamine (manufactured by Nippon Nyukazai Co., Ltd., product name: Amino Alcohol MDA) was added, the mixture was heated to 160°C, and reacted for 1 hour. Then, the temperature was raised stepwise to 210°C at 10°C / h, and 678.7g of trimellitic anhydride was added and reacted for 1 hour. The pressure in the flask was then reduced, and the reaction was carried out under reduced pressure at 8kPa until the desired softening point was reached, obtaining resin A-4 as amine-modified polyester resin (A). The physical properties are shown in Table 1.

[0075] Manufacturing example A5 (resin A-5) Resin A-5 was obtained as a modified polyester resin in the same manner as in Production Example A2, except that the amounts of each component were changed as shown in Table 1. The physical properties are shown in Table 1.

[0076] Comparative manufacturing example A1 (resin A-11) 2856.4g of 1,2-propanediol was placed in a 10-liter four-neck flask equipped with a dehydration tube equipped with a nitrogen inlet tube, a distillation column flowing with hot water at 95°C, a stirrer and a thermocouple, and the mixture was heated to 100°C, after which 4456.4g of terephthalic acid and 40.0g of di(2-ethylhexanoate)tin(II) were added, the mixture was heated to 180°C, and reacted at 180°C for 1 hour. The mixture was then heated stepwise at 5°C / h to 235°C, and reacted at 235°C for 1 hour. The mixture was then cooled to 210°C, and 687.2g of trimellitic anhydride was added and reacted for 1 hour. The pressure in the flask was then reduced, and the mixture was reacted under reduced pressure at 8kPa until the desired softening point was reached, to obtain resin A-11 as an amorphous polyester resin. The physical properties are shown in Table 1.

[0077] [Table 1]

[0078] Manufacturing example B1 (resin B-1) 2950.0g of 1,6-hexanediol was placed in a 10-liter four-neck flask equipped with a dehydration tube equipped with a nitrogen inlet tube, a stirrer, and a thermocouple, and the temperature was raised to 100°C. After heating to 100°C, 5050.0g of sebacic acid and 36.0g of di(2-ethylhexanoate)tin(II) were added, and the temperature was raised to 140°C. After reacting for 1 hour, the temperature was raised to 150°C and reacted for 1 hour. Thereafter, the temperature was raised stepwise at 10°C / h to 200°C, and the reaction was carried out under reduced pressure at 8.0kPa until the desired softening point was reached, to obtain Resin B-1 as a crystalline polyester resin. The physical properties are shown in Table 2.

[0079] [Table 2]

[0080] [Toner manufacturing] Examples 1 to 5 and Comparative Example 1 90 parts by mass of amorphous polyester resins A-1 to A-5 or amorphous polyester resin A-11 shown in Table 3, 10 parts by mass of resin B-1 as a crystalline polyester resin, 8 parts by mass of colorant "Regal 330R" (manufactured by CABOT Co., Ltd., carbon black), 5 parts by mass of release agent "HNP-9" (manufactured by Nippon Seiro Co., Ltd., paraffin wax (melting point 75 ° C.)), and 15 parts by mass of positively charged charge control agent "FCA-201-PS" (manufactured by Fujikura Kasei Co., Ltd.) were stirred for 3 minutes at a rotation speed of 1500 r / min (circumferential speed 21.6 m / sec) using a Henschel mixer, and then the mixture was mixed with a co-rotating twin-screw extruder (manufactured by Ikegai Co., Ltd., product name: PCM-30, shaft diameter 2.9 cm, shaft cross-sectional area 7.06 cm 2 The roll rotation speed was 200 r / min (circumferential speed 0.30 m / sec), the barrel temperature was set to 100° C., and the feed rate of the kneaded material was 10 kg / h. The kneaded product thus obtained was rolled and cooled with a cooling roll, and then coarsely pulverized to about 1 mm using a hammer mill. The coarsely pulverized product thus obtained was finely pulverized and classified using an air jet mill (manufactured by Nippon Pneumatic Co., Ltd., product name: IDS) to obtain a volume median particle size (D 50 ) toner base particles of 7.0 μm were obtained.

[0081] 100 parts by mass of the obtained toner base particles and 0.5 parts by mass of hydrophobic silica "TG-820F" (manufactured by Cabot Specialty Chemicals, Inc., number average particle size: 8 nm) as external additives, 2.0 parts by mass of hydrophobic silica "NA-50Y" (manufactured by Nippon Aerosil Co., Ltd., number average particle size: 30 nm), and 0.4 parts by mass of polytetrafluoroethylene fine particles "KTL-500F" (manufactured by Kitamura Co., Ltd., number average particle size: 500 nm) were mixed in a Henschel mixer (manufactured by Mitsui Mining Co., Ltd.) at 2100 r / min (circumferential speed: 29 m / sec) for 3 minutes to obtain a toner.

[0082] [Toner Evaluation] [Low temperature fixability and hot offset resistance] Each toner was mounted on a copy machine "AR-505" (manufactured by Sharp Corporation) with a modified fixing unit that allows fixing outside the machine, and a printout was obtained in an unfixed state (print area: 2 cm × 12 cm, adhesion amount: 0.5 mg / cm 2 ). Then, a fixing test was performed on the unfixed printed matter at each temperature while increasing the temperature of the fixing roll from 80°C to 240°C in increments of 5°C using a fixing machine (fixing speed 300mm / sec) adjusted to a total fixing pressure of 40kgf. A cellophane adhesive tape "UNICEF Cellophane" (manufactured by Mitsubishi Pencil Co., Ltd., width: 18mm, JIS Z1522) was applied to the image portion of the obtained printed matter, and the printed matter was passed through a fixing roller set at 30°C, after which the tape was peeled off. The optical reflection density before and after the tape was applied and peeled off was measured using a reflection densitometer "RD-915" (manufactured by GretagMacbeth Co., Ltd.), and the temperature of the fixing roller at which the ratio of the two (after peeling / before application x 100) first exceeded 90% was determined as the minimum fixing temperature. The lower the minimum fixing temperature, the better the low-temperature fixing property. The results are shown in Table 3. The fixed image obtained above was visually inspected, and the lowest temperature of the fixing roll at which hot offset was observed was recorded as the hot offset temperature. 2 The higher the hot offset temperature, the better the hot offset resistance. The results are shown in Table 3. The fixing temperature range was determined as the difference between the minimum fixing temperature obtained above and the hot offset temperature.

[0083] [Table 3]

[0084] From the results of the Examples and Comparative Examples, it was found that the toner of the Examples, which contains an amine-modified polyester resin as an amorphous polyester resin, is excellent in low-temperature fixing property and hot offset resistance, and expands the fixing temperature range. On the other hand, the toner of the comparative example containing an amorphous polyester resin instead of an amine-modified polyester resin showed no improvement in either low-temperature fixing property or hot offset resistance, and the fixing temperature range was extremely narrow.

Claims

1. A toner comprising an amorphous polyester resin, a crystalline polyester resin, and a wax, the amorphous polyester resin contains an amine-modified polyester resin (A) obtained by condensing an amine compound with a polycondensate of an alcohol component and a carboxylic acid component, The alcohol component contains 60 mol% or more of an aliphatic diol, The toner, wherein the crystalline polyester resin has an acid value of 20 mgKOH / g or more.

2. 2. The toner according to claim 1, wherein the amine-modified polyester resin (A) contains 0.5% by mass or more and 10% by mass or less of a structural unit derived from an amine compound.

3. 3. The toner according to claim 1, wherein the amine compound is selected from the group consisting of N-methyldiethanolamine, 2-diethylaminoethanol, and 2-dibutylaminoethanol.

4. 3. The toner according to claim 1, wherein a mass ratio of the crystalline polyester resin to the amine-modified polyester resin (A) (crystalline polyester resin / amine-modified polyester resin (A)) is 0.03 or more and 0.4 or less.

5. 3. The toner according to claim 1, wherein the content of the wax is from 1% by mass to 10% by mass.