JP2021148916A - toner - Google Patents

Abstract

To provide a toner that is excellent in hot offset resistance and can prevent the occurrence of a dash mark, while including an amorphous polyester resin as a binder resin.SOLUTION: A toner includes toner particles. The toner particles each include a toner base particle containing a binder resin and a mold release agent. The binder resin contains an amorphous polyester resin and a styrene acrylic resin. The amount of the styrene acrylic resin is 20 parts by mass or more and 50 parts by mass or less based on 100 parts by mass of the amorphous polyester resin. In an infrared absorption spectrum of the styrene acrylic resin obtained through infrared spectroscopic analysis, the ratio of the absorbance at the maximum peak within a range of a wave number of 3075 cm-1 or more and 3100 cm-1 or less to the absorbance at the maximum peak within a range of a wave number of 3040 cm-1 or more and 3074 cm-1 or less, is 0.40 or more and 0.70 or less.SELECTED DRAWING: None

Description

The present invention relates to toner.

Amorphous polyester resin is widely used as a binder resin for the purpose of ensuring low-temperature fixability of toner. For example, Patent Document 1 describes a toner containing an amorphous polyester resin as a binder resin.

JP-A-2017-125916

However, when a non-crystalline polyester resin is used as the binder resin, it is difficult to obtain a toner that is excellent in hot offset resistance and can suppress the generation of dash marks only by the technique disclosed in Patent Document 1.

The "dash mark" is a short line arranged parallel to the printing direction. However, when printing a solid image, the dash marks may appear as short white lines arranged parallel to the printing direction in the solid image. The cause of the dash mark is, for example, that the toner mother particles adhere to the photoconductor drum via the release agent present on the surface of the toner mother particles. The lower the dispersibility of the release agent in the toner mother particles, the more likely it is that dash marks will occur.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a toner which is excellent in hot offset resistance and can suppress the generation of dash marks while containing an amorphous polyester resin as a binder resin. It is to be.

The toner according to the present invention contains toner particles. The toner particles contain toner mother particles containing a binder resin and a mold release agent. The binding resin includes an amorphous polyester resin and a styrene acrylic resin. The styrene acrylic resin has a first repeating unit represented by the following general formula (1) and a second repeating unit represented by the following general formula (2). The amount of the styrene acrylic resin is 20 parts by mass or more and 50 parts by mass or less with respect to 100 parts by mass of the non-crystalline polyester resin. In the infrared absorption spectrum of the styrene-acrylic resin obtained by infrared spectroscopic analysis, with respect to the absorbance of the maximum peak of wavenumber 3040cm ^-1 or 3074cm ^-1 following areas, the maximum peak of wavenumber 3075cm ^-1 or 3100 cm ^-1 following areas The absorbance ratio of is 0.40 or more and 0.70 or less.

In the general formula (1), R ¹¹ and R ¹² each independently represent a hydrogen atom, a halogen atom, or an alkyl group having 1 or more and 6 or less carbon atoms. R ¹³ , R ¹⁴ , R ¹⁵ , R ¹⁶ and R ¹⁷ each independently represent a hydrogen atom, a halogen atom, a hydroxyl group, or an alkyl group having 1 or more and 6 or less carbon atoms. However, ^{at least one of R 13} , R ¹⁴ , R ¹⁵ , R ¹⁶ and R ¹⁷ represents a hydrogen atom.

In the general formula (2), R ²¹ and R ²² independently represent a hydrogen atom, a halogen atom, or an alkyl group having 1 or more and 6 or less carbon atoms. R ³ represents an alkylene group having 1 or more and 6 or less carbon atoms. R ⁴ and R ⁵ each independently represent a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. However, ^{at least one of R 4} and R ⁵ represents an alkyl group having 1 to 6 carbon atoms.

According to the present invention, it is possible to provide a toner that contains a non-crystalline polyester resin as a binder resin, has excellent hot offset resistance, and can suppress the occurrence of dash marks.

Hereinafter, preferred embodiments of the present invention will be described. First, terms used in the present specification will be described. Toner is an aggregate of toner particles (for example, powder). The external additive is an aggregate of external additive particles (for example, powder). Unless otherwise specified, the evaluation results (values indicating the shape, physical properties, etc.) of the powder (more specifically, the powder of the toner particles, the powder of the external additive particles, etc.) are obtained from the powder. It is the number average of the values measured for each of the particles selected in a considerable number.

_{Unless otherwise specified, the measured value of the volume median diameter (D 50} ) of the particles (more specifically, the powder of the particles) is a laser diffraction / scattering type particle size distribution measuring device (“LA-” manufactured by HORIBA, Ltd.). It is a volume-based median diameter measured using 950 ”). Unless otherwise specified, the average primary particle size of the number of powders should be determined using a scanning electron microscope (“JSM-7401F” manufactured by JEOL Ltd.) and image analysis software (“WinROOF” manufactured by Mitani Shoji Co., Ltd.). It is the number average value of the measured circle-equivalent diameters of 100 primary particles (Haywood diameter: the diameter of a circle having the same area as the projected area of the primary particles). Unless otherwise specified, the number average primary particle size of the particles refers to the number average primary particle size of the particles in the powder (the number average primary particle size of the powder).

The strength of chargeability is the ease of triboelectric charging, unless otherwise specified. For example, a standard carrier provided by the Japan Imaging Society (standard carrier for negatively charged polar toner: N-01, standard carrier for positively charged polar toner: P-01) and a measurement target (for example, toner) are mixed and stirred. Then, the measurement target is triboelectrically charged. Before and after triboelectric charging, for example, a suction-type compact charge amount measuring device (“MODEL 212HS” manufactured by Trek Co., Ltd.) measures the charge amount to be measured. The larger the change in the amount of charge before and after triboelectric charging, the stronger the chargeability.

Unless otherwise specified, the measured acid value is a value measured according to the neutralization titration method specified in "JIS (Japanese Industrial Standards) K0070-1992".

The SP value (solubility parameter) is a parameter defined by the formula "SP value = (E / V) ^1/2 " (E: aggregation energy [cal / mol], V: molar volume [cm ³ / mol]). Yes, unless otherwise specified, it is a value calculated according to the Fedors calculation method (unit: (cal / cm ³ ) ^1/2 , temperature: 25 ° C.). Details of the calculation method of Fedors are described in "RF Fedors," Polymer Engineering and Science ", 1974, Vol. 14, No. 2, p147-154".

The "alkyl group having 1 or more and 6 or less carbon atoms" is linear or branched and unsubstituted. Examples of the alkyl group having 1 or more and 6 or less carbon atoms include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an s-butyl group, a t-butyl group, an n-pentyl group, and isopentyl. Groups include groups, neopentyl groups, and n-hexyl groups.

The "alkylene group having 1 or more and 6 or less carbon atoms" is linear or branched and unsubstituted. Examples of the alkylene group having 1 or more and 6 or less carbon atoms include a methylene group, an ethylene group, an n-propylene group, an isopropylene group, an n-butylene group, an n-pentylene group, and an n-hexylene group.

Hereinafter, the compound and its derivative may be collectively referred to by adding "system" after the compound name. When the compound name is followed by "system" to represent the polymer name, it means that the repeating unit of the polymer is derived from the compound or a derivative thereof. Acrylic and methacryl may be collectively referred to as "(meth) acrylic". The "styrene acrylic resin" is a copolymer of at least one kind of styrene-based monomer and at least one kind of acrylic acid-based monomer.

<Toner>
The toner according to this embodiment can be suitably used for developing an electrostatic latent image, for example, as a positively charged toner. The toner may be used as a one-component developer. Further, the toner and the carrier may be mixed using a mixing device (for example, a ball mill) to prepare a two-component developer.

The toner particles contained in the toner according to the present embodiment contain toner mother particles containing a binder resin and a mold release agent. The binder resin includes a non-crystalline polyester resin and a styrene acrylic resin. The styrene acrylic resin has a first repeating unit represented by the following general formula (1) and a second repeating unit represented by the following general formula (2). The amount of the styrene acrylic resin is 20 parts by mass or more and 50 parts by mass or less with respect to 100 parts by mass of the non-crystalline polyester resin. In the infrared absorption spectrum of the styrene-acrylic resin obtained by infrared spectroscopic analysis, with respect to the absorbance of the maximum peak of wavenumber 3040cm ^-1 or 3074cm ^-1 following areas, the maximum peak of wavenumber 3075cm ^-1 or 3100 cm ^-1 following areas The absorbance ratio is 0.40 or more and 0.70 or less.

In the general formula (1), R ¹¹ and R ¹² each independently represent a hydrogen atom, a halogen atom, or an alkyl group having 1 or more and 6 or less carbon atoms. R ¹³ , R ¹⁴ , R ¹⁵ , R ¹⁶ and R ¹⁷ each independently represent a hydrogen atom, a halogen atom, a hydroxyl group, or an alkyl group having 1 or more and 6 or less carbon atoms. However, ^{at least one of R 13} , R ¹⁴ , R ¹⁵ , R ¹⁶ and R ¹⁷ represents a hydrogen atom.

In the general formula (2), R ²¹ and R ²² independently represent a hydrogen atom, a halogen atom, or an alkyl group having 1 or more and 6 or less carbon atoms. R ³ represents an alkylene group having 1 or more and 6 or less carbon atoms. R ⁴ and R ⁵ each independently represent a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. However, ^{at least one of R 4} and R ⁵ represents an alkyl group having 1 to 6 carbon atoms.

Hereinafter, the styrene acrylic resin having the first repeating unit and the second repeating unit may be referred to as "specific styrene acrylic resin". In the infrared absorption spectrum of the specific styrene acrylic resin obtained by infrared spectroscopic analysis, ^{the maximum peak in the region of wave number 3040 cm -1} or more and 3074 cm ^-1 or less may be described as "first peak". Specific styrene-acrylic resin obtained by infrared spectroscopy in the infrared absorption spectrum, the maximum peak of wavenumber 3075cm ^-1 or 3100 cm ^-1 The following regions may be referred to as "second peak". The ratio of the absorbance of the second peak to the absorbance of the first peak (absorbance of the second peak / absorbance of the first peak) may be described as "specific IR ratio". The method for measuring the specific IR ratio is the same method as in Examples described later or a method similar thereto.

The first peak is a peak derived from the expansion and contraction vibration of the carbon atom constituting the benzene ring contained in the specific styrene acrylic resin and the hydrogen atom bonded to the carbon atom. The second peak is a peak derived from ^{5 -NR 4} R groups in the second repeating unit.

The specific IR ratio (absorbance of the second peak / absorbance of the first peak) is an index of the content ratio of the second repeating unit in the specific styrene acrylic resin. That is, the higher the specific IR ratio, the higher the content ratio of the second repeating unit in the specific styrene acrylic resin.

By providing the toner according to the present embodiment with the above-mentioned structure, it is possible to suppress the generation of dash marks while having excellent hot offset resistance while containing an amorphous polyester resin as a binder resin. The reason is presumed as follows.

In general, a toner containing an amorphous polyester resin as a binder resin has excellent low-temperature fixability. However, the amorphous polyester resin generally used as the binder resin has low compatibility with the release agent, which is a component that enhances the hot offset resistance of the toner. Therefore, when an image is formed using a toner containing a non-crystalline polyester resin and a mold release agent, dash marks tend to occur easily.

On the other hand, in general, the styrene acrylic resin is inferior to the amorphous polyester resin in the function of enhancing the low temperature fixability, but has high compatibility with the release agent. It is conceivable to use a non-crystalline polyester resin and a styrene acrylic resin together as the binder resin in order to improve the compatibility between the binder resin and the mold release agent while improving the low temperature fixability of the toner. , Non-crystalline polyester resin and styrene acrylic resin are difficult to be compatible with each other.

In the toner according to the present embodiment, the binder resin contains a non-crystalline polyester resin and a specific styrene acrylic resin. The specific styrene acrylic resin has a first repeating unit and a second repeating unit containing ^{an alkylamino group (more specifically, −NR 4} R ^{5 groups).} The alkylamino group contained in the specific styrene acrylic resin has a high affinity with the amorphous polyester resin. Further, in the toner according to the present embodiment, the specific IR ratio (an index of the content ratio of the second repeating unit in the specific styrene acrylic resin) is 0.40 or more and 0.70 or less. Further, in the toner according to the present embodiment, the amount of the specific styrene acrylic resin is 20 parts by mass or more and 50 parts by mass or less with respect to 100 parts by mass of the non-crystalline polyester resin. From these facts, in the toner according to the present embodiment, the non-crystalline polyester resin and the specific styrene acrylic resin are appropriately compatible with each other, and the binder resin and the release agent are appropriately compatible with each other. As a result, in the toner according to the present embodiment, the release agent is appropriately dispersed in the toner mother particles. Therefore, the toner according to the present embodiment has excellent hot offset resistance and can suppress the occurrence of dash marks while containing a non-crystalline polyester resin as the binder resin.

In the present embodiment, in order to obtain a toner that is superior in hot offset resistance and can further suppress the generation of dash marks, the SP value of the amorphous polyester resin is set to SP _E, and the SP value of the specific styrene acrylic resin is set to SP. _{When S} is set, it is preferable to satisfy the relationship of _{| SP E} −SP _S | ≦ 1.2 (cal / cm ³ ) ^1/2. | SP _E −SP _S | is the absolute value of the difference between _{SP E} and SP _S. Hereinafter, | SP _E −SP _S | may be referred to as a ΔSP value. The lower limit of the ΔSP value is not particularly limited and may be 0.0 (cal / cm ³ ) ^1/2 .

The toner particles contained in the toner according to the present embodiment may further include an external additive. When the toner particles further include an external additive, the toner particles include a toner mother particle containing a binder resin and a mold release agent, and an external additive adhering to the surface of the toner mother particle. If it is not necessary, the external additive may be omitted. When the external additive is omitted, the toner mother particles correspond to the toner particles.

The toner particles contained in the toner according to the present embodiment may be toner particles not provided with a shell layer, or may be toner particles having a shell layer (hereinafter, may be referred to as capsule toner particles). good. In the capsule toner particles, the toner mother particles include a toner core containing a binder resin and a mold release agent, and a shell layer covering the surface of the toner core. The shell layer contains resin. For example, by covering the toner core that melts at a low temperature with a shell layer having excellent heat resistance, it is possible to achieve both heat-resistant storage stability and low-temperature fixability of the toner. Additives may be dispersed in the resin constituting the shell layer. The shell layer may cover the entire surface of the toner core or may partially cover the surface of the toner core.

In the present embodiment, the toner mother particles are, if necessary, at least one of an internal additive other than the mold release agent (for example, a colorant, a charge control agent, and a magnetic powder) in addition to the binder resin and the mold release agent. ) May be further contained.

In the present embodiment, in order to obtain a toner suitable for image formation, the volume median diameter (D ₅₀ ) of the toner matrix particles is preferably 4 μm or more and 9 μm or less.

Next, the components contained in the toner (more specifically, the toner particles) according to the present embodiment will be described.

[Bundling resin]
For example, the binder resin occupies 70% by mass or more of all the components of the toner mother particles. Therefore, it is considered that the properties of the binder resin have a great influence on the properties of the entire toner matrix particles. The binder resin includes a non-crystalline polyester resin and a specific styrene acrylic resin. Further, the binder resin may contain a resin other than the amorphous polyester resin and the specific styrene acrylic resin. However, in order to obtain a toner that is superior in hot offset resistance and can further suppress the generation of dash marks, the total content of the non-crystalline polyester resin and the specific styrene acrylic resin is set with respect to the total amount of the binder resin. It is preferably 70% by mass or more and 100% by mass or less, and more preferably 85% by mass or more and 100% by mass or less.

(Amorphous polyester resin)
Non-crystalline polyester resin refers to a polyester resin in which no clear endothermic peak is observed in the endothermic curve measured using a differential scanning calorimeter. The binder resin may contain one kind of non-crystalline polyester resin alone, or may contain a plurality of kinds of non-crystalline polyester resins.

The polyester resin is obtained by polycondensing one or more polyhydric alcohols and one or more polyvalent carboxylic acids. Examples of the polyhydric alcohol for synthesizing the polyester resin include dihydric alcohols (more specifically, aliphatic diols, bisphenols, etc.) as shown below, and trihydric or higher alcohols. Examples of the polyvalent carboxylic acid for synthesizing a polyester resin include a divalent carboxylic acid and a trivalent or higher carboxylic acid as shown below. In addition, instead of the polyvalent carboxylic acid, a polyvalent carboxylic acid derivative capable of forming an ester bond by condensation polymerization (more specifically, an anhydride of the polyvalent carboxylic acid, a polyvalent carboxylic acid halide, etc.) may be used. good.

Preferable examples of aliphatic diols include diethylene glycol, triethylene glycol, neopentyl glycol, 1,2-propanediol, α, ω-alkanediol (more specifically, ethylene glycol, 1,3-propanediol, etc.). 1,4-Butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,12-dodecanediol, etc.) , 2-Buten-1,4-diol, 1,4-cyclohexanedimethanol, dipropylene glycol, polyethylene glycol, polypropylene glycol, and polytetramethylene glycol.

Preferable examples of bisphenol include bisphenol A, hydrogenated bisphenol A, bisphenol A ethylene oxide adduct, and bisphenol A propylene oxide adduct.

Preferable examples of trihydric or higher alcohols are sorbitol, 1,2,3,6-hexanetetrol, 1,4-sorbitan, pentaerythritol, dipentaerythritol, tripentaerythritol, 1,2,4-butane. Triol, 1,2,5-pentanetriol, glycerol, diglycerol, 2-methylpropanetriol, 2-methyl-1,2,4-butanetriol, trimethylolethane, trimethylolpropane, and 1,3,5- Examples include trihydroxymethylbenzene.

Preferable examples of divalent carboxylic acids are maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, phthalic acid, isophthalic acid, terephthalic acid, cyclohexanedicarboxylic acid, adipic acid, sebacic acid, azelaic acid, malonic acid. , 1,10-decandicarboxylic acid, succinic acid, alkylsuccinic acid (more specifically, n-butylsuccinic acid, isobutylsuccinic acid, n-octylsuccinic acid, n-dodecylsuccinic acid, isododecylsuccinic acid, etc.), And alkenyl succinic acid (more specifically, n-butenyl succinic acid, isobutenyl succinic acid, n-octenyl succinic acid, n-dodecenyl succinic acid, isododecenyl succinic acid, etc.).

Preferable examples of trivalent or higher valent carboxylic acids are 1,2,4-benzenetricarboxylic acid (trimellitic acid), 2,5,7-naphthalenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, 1, 2,4-Butantricarboxylic acid, 1,2,5-hexanetricarboxylic acid, 1,3-dicarboxy-2-methyl-2-methylenecarboxypropane, 1,2,4-cyclohexanetricarboxylic acid, tetra (methylenecarboxyl) Examples include methane, 1,2,7,8-octanetetracarboxylic acid, pyromellitic acid, and empole trimeric acid.

Suitable polyhydric alcohols for synthesizing non-crystalline polyester resins include bisphenols (more specifically, bisphenol A ethylene oxide adducts, bisphenol A propylene oxide adducts, etc.). Suitable polyvalent carboxylic acids for synthesizing non-crystalline polyester resins include aromatic dicarboxylic acids (more specifically, terephthalic acid and the like) and adipic acid.

(Specific styrene acrylic resin)
The specific styrene acrylic resin has a first repeating unit represented by the general formula (1) and a second repeating unit represented by the general formula (2). The binder resin may contain one kind of specific styrene acrylic resin alone, or may contain a plurality of kinds of specific styrene acrylic resins.

^{As R 11} and R ¹² in the general formula (1), a hydrogen atom or a methyl group is preferable, and a hydrogen atom is more preferable, respectively. ^{As R 13} , R ¹⁴ , R ¹⁵ , R ¹⁶ and R ^{17 in the} general formula (1), a hydrogen atom or a halogen atom is preferable, and a hydrogen atom is more preferable, respectively.

^{As R 21} and R ²² in the general formula (2), a hydrogen atom or a methyl group is preferable independently of each other. ^{As R 3} in the general formula (2), an ethylene group, an n-propylene group or an isopropylene group is preferable, and an ethylene group is more preferable. ^{As R 4} and R ⁵ in the general formula (2), an alkyl group having 1 to 6 carbon atoms is preferable, and a methyl group is more preferable, respectively.

Examples of the monomer giving the first repeating unit include styrene, alkylstyrene (more specifically, α-methylstyrene, p-ethylstyrene, 4-t-butylstyrene, etc.), p-hydroxystyrene, m-hydroxy. Styrene, and styrene halides (more specifically, p-chlorostyrene, 2,6-dichlorostyrene, p-bromostyrene, 2,4,5-tribromostyrene, 2,4,6-tribromostyrene, etc. ). In order to obtain a toner that is more excellent in hot offset resistance and can further suppress the generation of dash marks, styrene is preferable as the monomer that gives the first repeating unit.

In order to obtain a toner that is more excellent in hot offset resistance and can further suppress the generation of dash marks, the content of the first repeating unit with respect to all the repeating units of the specific styrene acrylic resin is 15% by mass or more and 25% by mass or less. It is preferable to have.

Examples of the monomer giving the second repeating unit include 2- (dimethylamino) ethyl (meth) acrylate, 2- (diethylamino) ethyl (meth) acrylate, 2- (dimethylamino) propyl (meth) acrylate, and the like. And 2- (diethylamino) propyl (meth) acrylate. In order to obtain a toner that is more excellent in hot offset resistance and can further suppress the generation of dash marks, 2- (dimethylamino) ethyl (meth) acrylic acid is preferable as the monomer that gives the second repeating unit, and acrylic acid. 2- (Dimethylamino) ethyl is more preferred.

In order to obtain a toner that is superior in hot offset resistance and can further suppress the generation of dash marks, the content of the second repeating unit with respect to all the repeating units of the specific styrene acrylic resin should be 5% by mass or more and 15% by mass or less. It is preferable to have.

In order to obtain a toner that is more excellent in hot offset resistance and can further suppress the generation of dash marks, the first repeating unit is a repeating unit derived from styrene, and the second repeating unit is 2- (dimethylamino) acrylic acid. ) It is preferably a repeating unit derived from ethyl.

The specific styrene acrylic resin may further have a repeating unit other than the first repeating unit and the second repeating unit (hereinafter, may be referred to as “another repeating unit”). Examples of other repeating units include a third repeating unit derived from divinylbenzene and a fourth repeating unit represented by the following general formula (3).

In the general formula (3), R ³¹ and R ³² each independently represent a hydrogen atom, a halogen atom, or an alkyl group having 1 or more and 6 or less carbon atoms. R ³³ represents an alkyl group having 1 or more carbon atoms and 6 or less carbon atoms. As R ³¹ and R ³² , a hydrogen atom or a methyl group is preferable independently of each other. As R ³³ , an n-butyl group is preferable.

Divinylbenzene, which gives a third repeating unit, functions as a cross-linking agent when synthesizing a specific styrene acrylic resin. Therefore, when the specific styrene acrylic resin has the third repeating unit, a toner having excellent heat-resistant storage stability can be obtained. In order to obtain a toner having better heat storage stability, the content of the third repeating unit with respect to all the repeating units of the specific styrene acrylic resin is preferably 0.05% by mass or more and 0.20% by mass or less.

Examples of the monomer giving the fourth repeating unit include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, and n-butyl (meth) acrylate. , And isobutyl (meth) acrylate. In order to obtain a toner that is more excellent in hot offset resistance and can further suppress the generation of dash marks, n-butyl (meth) acrylate is preferable as the monomer that gives the fourth repeating unit, and n-butyl acrylate is used. More preferred.

The specific IR ratio and the ΔSP value can be adjusted, for example, by changing the content of the second repeating unit with respect to all the repeating units of the specific styrene acrylic resin.

As described above, the first peak is a peak derived from the expansion and contraction vibration of the carbon atom constituting the benzene ring and the hydrogen atom bonded to the carbon atom. Examples of the benzene ring include the benzene ring in the first repeating unit. Hereinafter, the expansion / contraction vibration between the carbon atom constituting the benzene ring in the first repetition unit and the hydrogen atom bonded to the carbon atom may be referred to as the first expansion / contraction vibration.

When the specific styrene acrylic resin further has a third repeating unit, the first peak is, for example, expansion and contraction vibration between the carbon atom constituting the benzene ring in the third repeating unit and the hydrogen atom bonded to the carbon atom, and It is derived from at least one of the first expansion and contraction vibrations.

Further, as described above, the second peak is a peak derived from ^{-NR 4} R ^{5 groups in the second repeating unit. Examples of the peak derived from the -NR 4} R ⁵ group in the second repeating unit include a peak derived from the CH stretching vibration in at least one of ^{R 4} and R ^5.

(Other resins)
As described above, the toner mother particles may further contain a resin other than the non-crystalline polyester resin and the specific styrene acrylic resin (hereinafter, may be referred to as “other resin”) as the binder resin. .. Examples of other resins include crystalline polyester resin, styrene resin, acrylic acid ester resin, olefin resin (more specifically, polyethylene resin, polypropylene resin, etc.), and vinyl resin (more specifically, Vinyl chloride resin, polyvinyl alcohol, vinyl ether resin, N-vinyl resin, etc.), polyamide resin, and urethane resin can be mentioned. Further, a copolymer of each of these resins, that is, a copolymer in which an arbitrary repeating unit is introduced into the above resin (more specifically, a styrene-butadiene resin or the like) can also be used as another resin.

Since the crystalline polyester resin functions as a plasticizer, the toner matrix particles containing the crystalline polyester resin tend to be easily softened at the time of fixing. Therefore, in order to obtain a toner having excellent low-temperature fixability, it is preferable that the toner matrix particles contain a crystalline polyester resin as another resin. Crystalline polyester resin refers to a polyester resin in which a clear endothermic peak is observed in an endothermic curve measured using a differential scanning calorimeter.

Suitable polyhydric alcohols for synthesizing crystalline polyester resins include α, ω-alkanediols having 2 or more and 8 or less carbon atoms (more specifically, ethylene glycol, 1,4-butanediol, 1,1). 6-Hexanediol, etc.). Suitable polyvalent carboxylic acids for synthesizing crystalline polyester resins include α, ω-alkanedicarboxylic acids (more specifically) having 4 or more and 10 or less carbon atoms (including carbon atoms of two carboxy groups). , Succinic acid, sebacic acid, etc.).

In order to obtain a toner having better low-temperature fixability, the amount of the crystalline polyester resin is preferably 10 parts by mass or more and 30 parts by mass or less, preferably 15 parts by mass or more, with respect to 100 parts by mass of the non-crystalline polyester resin. It is more preferably 25 parts by mass or less.

(Preferable combination of binder resins)
In order to obtain a toner having further excellent hot offset resistance, further suppressing the occurrence of dash marks, and excellent low temperature fixability, it is preferable to satisfy the following condition 1. Further, in order to obtain a toner which is further excellent in hot offset resistance, can further suppress the occurrence of dash marks, and is excellent in low temperature fixability and heat storage stability, it is preferable to satisfy the following condition 2.
Condition 1: The specific styrene acrylic resin has a repeating unit derived from styrene as the first repeating unit and a repeating unit derived from 2- (dimethylamino) ethyl acrylate as the second repeating unit, and the binder resin is crystalline. Further contains polyester resin.
Condition 2: The above condition 1 is satisfied, and the specific styrene acrylic resin further has a third repeating unit (repetition unit derived from divinylbenzene).

[Release agent]
The toner mother particles contain a mold release agent. In order to obtain a toner having more excellent hot offset resistance, the amount of the release agent is preferably 7 parts by mass or more, and more preferably 8 parts by mass or more with respect to 100 parts by mass of the binder resin. .. Further, in order to obtain a toner capable of further suppressing the generation of dash marks, the amount of the release agent is preferably 10 parts by mass or less, and 9 parts by mass or less with respect to 100 parts by mass of the binder resin. Is more preferable.

Examples of the release agent include ester wax, polyolefin wax (more specifically, polyethylene wax, polypropylene wax, etc.), microcrystalline wax, fluororesin wax, Fishertropch wax, paraffin wax, candelilla wax, and Montan wax. And Custer wax. Examples of the ester wax include natural ester wax (more specifically, carnauba wax, rice wax, etc.) and synthetic ester wax. In the present embodiment, one type of release agent may be used alone, or a plurality of types of release agents may be used in combination. Synthetic ester wax is preferable as the release agent in order to obtain a toner that is more excellent in hot offset resistance and can further suppress the generation of dash marks.

A compatibilizer may be added to the toner matrix particles in order to improve the compatibility between the binder resin and the release agent.

[Colorant]
The toner mother particles may contain a colorant. As the colorant, a pigment or dye known according to the color of the toner can be used. In order to form a high-quality image using the toner, the amount of the colorant is preferably 1 part by mass or more and 20 parts by mass or less with respect to 100 parts by mass of the binder resin.

The toner mother particles may contain a black colorant. An example of a black colorant is carbon black. Further, the black colorant may be a colorant that has been adjusted to black by using a yellow colorant, a magenta colorant, and a cyan colorant.

The toner mother particles may contain a color colorant. Examples of the color colorant include a yellow colorant, a magenta colorant, and a cyan colorant.

As the yellow colorant, for example, one or more compounds selected from the group consisting of condensed azo compounds, isoindolinone compounds, anthraquinone compounds, azo metal complexes, methine compounds, and arylamide compounds can be used. Examples of the yellow colorant include C.I. I. Pigment Yellow (3, 12, 13, 14, 15, 17, 62, 74, 83, 93, 94, 95, 97, 109, 110, 111, 120, 127, 128, 129, 147, 151, 154, 155 168, 174, 175, 176, 180, 181, 191 and 194), Naphthol Yellow S, Hansa Yellow G, and C.I. I. Bat yellow can be mentioned.

The magenta colorant is selected from the group consisting of, for example, condensed azo compounds, diketopyrrolopyrrole compounds, anthraquinone compounds, quinacridone compounds, basic dye lake compounds, naphthol compounds, benzimidazolone compounds, thioindigo compounds, and perylene compounds. One or more compounds can be used. Examples of the magenta colorant include C.I. I. Pigment Red (2, 3, 5, 6, 7, 19, 23, 48: 2, 48: 3, 48: 4, 57: 1, 81: 1, 122, 144, 146, 150, 166, 169, 177 , 184, 185, 202, 206, 220, 221 and 254).

As the cyan colorant, for example, one or more compounds selected from the group consisting of copper phthalocyanine compounds, anthraquinone compounds, and base dye lake compounds can be used. Examples of the cyan colorant include C.I. I. Pigment Blue (1, 7, 15, 15: 1, 15: 2, 15: 3, 15: 4, 60, 62, and 66), Phthalocyanine Blue, C.I. I. Bat Blue, as well as C.I. I. Acid blue can be mentioned.

[Charge control agent]
The toner mother particles may contain a charge control agent. The charge control agent is used, for example, to obtain a toner having excellent charge stability or charge rise characteristics. The charge rising characteristic of the toner is an index of whether or not the toner can be charged to a predetermined charge level in a short time.

By incorporating a positively chargeable charge control agent into the toner mother particles, the cationicity (positive chargeability) of the toner mother particles can be strengthened. Further, by incorporating a negative charge control agent into the toner mother particles, the anionic property (negative charge property) of the toner mother particles can be strengthened.

Examples of positively charged charge control agents include pyridazine, pyrimidine, pyrazine, 1,2-oxazine, 1,3-oxazine, 1,4-oxazine, 1,2-thiazine, 1,3-thiazine, 1, 4-Thiadine, 1,2,3-triazine, 1,2,4-triazine, 1,3,5-triazine, 1,2,4-oxadiazine, 1,3,4-oxadiazine, 1,2,6- Oxaziazine, 1,3,4-triazine, 1,3,5-triazine, 1,2,3,4-tetrazine, 1,2,4,5-tetrazine, 1,2,3,5-tetrazine, 1, Adin compounds such as 2,4,6-oxatriazine, 1,3,4,5-oxatriazine, phthalazine, quinazoline, quinoxalin; azine fast red FC, azine fast red 12BK, azine violet BO, azine brown 3G, azine light Direct dyes such as Brown GR, Triazine Dark Green BH / C, Triazine Deep Black EW, Triazine Deep Black 3RL; Acidic dyes such as Niglosin BK, Niglosin NB, Niglosin Z; Alkylated amines; Alkylamides; benzyldecylhexylmethyl Tertiary ammonium salts such as ammonium chloride, decyltrimethylammonium chloride, 2- (methacryloyloxy) ethyltrimethylammonium chloride, dimethylaminopropylacrylamide methyl tetrachloride; resins containing a quaternary ammonium cation group can be mentioned. Only one of these charge control agents may be used, or two or more types of charge control agents may be used in combination.

An example of a negatively charged charge control agent is an organometallic complex which is a chelate compound. As the organometallic complex, one or more selected from the group consisting of an acetylacetone metal complex, a salicylic acid-based metal complex, and salts thereof is preferable.

In order to obtain a toner having excellent charge stability, the content of the charge control agent is preferably 0.1 part by mass or more and 20 parts by mass or less with respect to 100 parts by mass of the binder resin.

[Magnetic powder]
The toner mother particles may contain magnetic powder. Examples of the material of the magnetic powder include ferromagnetic metals (more specifically, iron, cobalt, nickel, etc.) and their alloys, ferromagnetic metal oxides (more specifically, ferrite, magnetite, chromium dioxide, etc.). , And a material that has been subjected to a ferromagnetism treatment (more specifically, a carbon material to which ferromagnetism has been imparted by heat treatment, etc.). In the present embodiment, one kind of magnetic powder may be used alone, or a plurality of kinds of magnetic powder may be used in combination.

[External agent]
The toner particles contained in the toner according to the present embodiment may further include an external additive (powder of external additive particles) adhering to the surface of the toner matrix particles. In the present embodiment, one kind of external additive particles may be used alone, or a plurality of kinds of external additive particles may be used in combination.

In order to obtain a toner having excellent fluidity, inorganic oxide particles are preferable as the external additive particles constituting the external additive, and silica particles and metal oxides (more specifically, alumina, titanium oxide, etc.) More preferably, one or more selected from the group consisting of particles of magnesium oxide, zinc oxide, strontium titanate, barium titanate, etc.).

In order to obtain a toner having excellent fluidity, the average number of primary particle diameters of the external additive particles constituting the external additive is preferably 5 nm or more and 50 nm or less.

The external additive particles may be surface-treated. For example, when silica particles are used as the external additive particles, the surface of the silica particles may be imparted with hydrophobicity and / or positive chargeability by a surface treatment agent. Examples of the surface treatment agent include a coupling agent (more specifically, a silane coupling agent, a titanate coupling agent, an aluminate coupling agent, etc.), a silazane compound (more specifically, a chain silazane compound, etc.). Cyclic silane compounds and the like) and silicone oils (more specifically, dimethyl silicone oils and the like) can be mentioned. As the surface treatment agent, one or more selected from the group consisting of a silane coupling agent and a silazane compound is particularly preferable. Preferable examples of the silane coupling agent include silane compounds (more specifically, methyltrimethoxysilane, aminosilane, etc.). Preferable examples of the silazane compound include HMDS (hexamethyldisilazane). When the surface of the silica substrate (untreated silica particles) is treated with a surface treatment agent, a large number of hydroxyl groups (-OH) present on the surface of the silica substrate are partially or wholly derived from the surface treatment agent. Substituted for a functional group. As a result, silica particles having a functional group derived from the surface treatment agent (specifically, a functional group having a more hydrophobic and / or positively charged property than a hydroxyl group) on the surface can be obtained.

In order to fully exert the function of the external additive while suppressing the detachment of the external additive from the toner mother particles, the amount of the external additive is 0.1 mass by mass with respect to 100 parts by mass of the toner mother particles. It is preferably 10 parts or more and 10.0 parts by mass or less.

<Toner manufacturing method>
Next, a preferred method for producing the toner according to the above-described embodiment will be described. Hereinafter, the description of the components overlapping with the toner according to the above-described embodiment will be omitted.

[Preparation process of toner matrix particles]
First, toner mother particles are prepared by an agglutination method or a pulverization method.

The agglutination method includes, for example, an agglutination step and a coalescence step. In the agglomeration step, fine particles containing components constituting the toner matrix particles are agglomerated in an aqueous medium to form agglomerated particles. In the coalescence step, the components contained in the aggregated particles are coalesced in an aqueous medium to form toner matrix particles.

Next, the pulverization method will be described. According to the pulverization method, toner matrix particles can be prepared relatively easily, and the manufacturing cost can be reduced. When the toner mother particles are prepared by the crushing method, the toner mother particles preparation step includes, for example, a melt-kneading step and a crushing step. The toner matrix particle preparation step may further include a mixing step before the melt kneading step. Further, the toner matrix particle preparation step may further include at least one of a fine pulverization step and a classification step after the pulverization step.

In the mixing step, the binder resin, the release agent, and other internal additives added as needed are mixed to obtain a mixture. In the melt-kneading step, the toner material is melted and kneaded to obtain a melt-kneaded product. As the toner material, for example, a mixture obtained in a mixing step is used. In the pulverization step, the obtained melt-kneaded product is cooled to, for example, room temperature (25 ° C.) and then pulverized to obtain a pulverized product. When it is necessary to reduce the diameter of the pulverized product obtained in the pulverization step, a step of further pulverizing the pulverized product (fine pulverization step) may be carried out. Further, when the particle size of the crushed product is made uniform, a step of classifying the obtained crushed product (classification step) may be carried out. By the above steps, toner mother particles which are pulverized products can be obtained.

[External process]
Then, if necessary, the obtained toner mother particles and the external additive are mixed using a mixer (for example, FM mixer manufactured by Nippon Coke Industries Co., Ltd.) and externally added to the surface of the toner mother particles. The agent may be attached. The toner mother particles may be used as the toner particles without adhering the external additive to the toner mother particles. In this way, the toner (powder of toner particles) according to the above-described embodiment can be obtained.

Hereinafter, examples of the present invention will be described, but the present invention is not limited to the scope of the examples. First, a method for measuring a specific IR ratio of a styrene acrylic resin will be described.

<Measurement method of specific IR ratio>
As a measuring device, FT-IR (Fourier Transform Infrared Spectroscopy) (“Frontier” manufactured by PerkinElmer) was used. The measurement mode was ATR (total reflection measurement method) mode. Diamond (refractive index 2.4) was used as the ATR crystal.

The ATR crystal was mounted on a measuring device, and 1 mg of a sample (measurement target: any of styrene acrylic resins SAc-1 to SAc-4 described later) was placed on the ATR crystal. Subsequently, the sample was pressurized with a load of 60 N or more and 80 N or less using the pressure arm of the measuring device. Subsequently, the FT-IR spectrum (horizontal axis: wave number of irradiated infrared rays, vertical axis: absorbance) of the sample was measured under the condition of an infrared light incident angle of 45 °. From the obtained FT-IR spectrum, the absorbance of the first peak and the absorbance of the second peak were obtained. The first peak appeared near ^{3050 cm -1.} The second peak appeared near ^{3090 cm -1.} Then, the absorbance of the second peak was divided by the absorbance of the first peak to obtain a specific IR ratio (absorbance of the second peak / absorbance of the first peak).

<Synthesis of binding resin>
Next, the methods for synthesizing the non-crystalline polyester resin PE-1, the crystalline polyester resin PE-2, and the styrene acrylic resins SAc-1 to SAc-4 used as the binder resin will be described.

[Synthesis of amorphous polyester resin PE-1]
A 2 L capacity four-necked flask equipped with a thermometer (thermocouple), a dehydration tube, a nitrogen introduction tube, and a stirrer was set in a mantle heater. Subsequently, 150 g of the bisphenol A ethylene oxide adduct (average number of moles of ethylene oxide added: 2 mol), 50 g of the bisphenol A propylene oxide adduct (average number of moles of propylene oxide added: 2 mol), and terephthal were placed in the flask. 50 g of the acid, 30 g of adipic acid and 54 g of tin (II) 2-ethylhexanoate were added. Subsequently, after the inside of the flask was made into a nitrogen atmosphere, the flask was heated over 2 hours until the temperature inside the flask reached 235 ° C. Subsequently, the contents of the flask were reacted under the conditions of a nitrogen atmosphere and a temperature of 235 ° C. until the reaction rate reached 90% by mass. The reaction rate was calculated according to the formula “reaction rate = 100 × actual amount of reaction-generated water / theoretically produced amount of water”. Subsequently, the contents of the flask were reacted until the acid value of the reaction product (resin) reached a predetermined value (15 mgKOH / g) under the conditions of a reduced pressure atmosphere (pressure 8 kPa) and a temperature of 235 ° C., and the SP value was 11. A 2 (cal / cm ³ ) ^1/2 non-crystalline polyester resin PE-1 was obtained.

[Synthesis of crystalline polyester resin PE-2]
A 2 L capacity four-necked flask equipped with a thermometer (thermocouple), a dehydration tube, a nitrogen introduction tube, and a stirrer was set in a mantle heater. Subsequently, 69 g of ethylene glycol, 214 g of sebacic acid, and 54 g of tin (II) 2-ethylhexanoate were placed in the flask. Subsequently, after the inside of the flask was made into a nitrogen atmosphere, the flask was heated over 2 hours until the temperature inside the flask reached 235 ° C. Subsequently, the contents of the flask were reacted in a nitrogen atmosphere and a temperature of 235 ° C. until the reaction rate represented by the above formula reached 95% by mass, and then in a reduced pressure atmosphere (pressure 8 kPa) and a temperature of 210 ° C. Then, the contents of the flask were reacted for 1 hour. Subsequently, the contents of the flask were reacted for 1 hour under the conditions of a reduced pressure atmosphere (pressure 40 kPa) and a temperature of 210 ° C. to obtain a crystalline polyester resin PE-2.

[Synthesis of styrene acrylic resin SAc-1]
In a reaction vessel equipped with a stirrer and a thermometer, 5058 g of ion-exchanged water, 22 g of a dispersant (“Eleminor® JS-20” manufactured by Sanyo Chemical Industries, Ltd.), 14 g of sodium sulfate, and an antifoaming agent (poly). Oxyalkylene pentaerythritol ether: 60 g of "Dishome (registered trademark) CE-457" manufactured by NOF CORPORATION was added. Subsequently, 700 g of 2- (dimethylamino) ethyl acrylate, 2136 g of styrene, 6740 g of n-butyl acrylate, 10 g of divinylbenzene (purity: 56.5% by mass), and 75 g of benzoyl peroxide as a polymerization initiator. And 14 g of t-butylperoxy-2-ethylhexyl monocarbonate (“Trigonox (registered trademark) 117” manufactured by Kayaku Akzo Corporation) as a polymerization initiator was added.

Subsequently, while stirring the contents of the container, the contents of the container were heated until the temperature reached 130 ° C. The temperature rise of the contents of the container was carried out over 65 minutes from 40 ° C. to 130 ° C. After the temperature of the container contents reached 130 ° C., the container contents were reacted (specifically, polymerization reaction) for another 2 hours. Then, the contents of the container were cooled to obtain a dispersion liquid of resin particles. The obtained dispersion was filtered (solid-liquid separated) with a metal mesh having an opening of 2 mm to obtain resin particles (powder). Subsequently, fine powder in the obtained resin particles (powder) was removed using a nylon filter cloth having an opening of 45 μm. Subsequently, the powder from which the fine powder had been removed was washed and then dried to obtain a styrene acrylic resin SAc-1 having ^{an SP value of 10.0 (cal / cm 3} ) ^1/2.

[Synthesis of styrene acrylic resin SAc-2]
^{SP value 10.3 (cal / cm 3} ) ^{1 by the} same method as the synthesis of styrene acrylic resin SAc-1, except that the amount of 2- (dimethylamino) ethyl acrylate used (input amount) was changed to 1400 g. A styrene acrylic resin SAc-2 of ^{/ 2 was obtained.}

[Synthesis of styrene acrylic resin SAc-3]
^{SP value 9.9 (cal / cm 3} ) ^{1 by the} same method as the synthesis of styrene acrylic resin SAc-1, except that the amount of 2- (dimethylamino) ethyl acrylate used (input amount) was changed to 500 g. A styrene acrylic resin SAc-3 of ^{/ 2 was obtained.}

[Synthesis of styrene acrylic resin SAc-4]
^{SP value 10.4 (cal / cm 3} ) ^{1 by the} same method as the synthesis of styrene acrylic resin SAc-1, except that the amount of 2- (dimethylamino) ethyl acrylate used (input amount) was changed to 1700 g. A styrene acrylic resin SAc-4 of ^{/ 2 was obtained.}

<Making toner>
[Preparation of toner TA-1]
In an FM mixer (“FM-20B” manufactured by Nippon Coke Industries Co., Ltd.), 100 parts by mass of non-crystalline polyester resin PE-1, 20 parts by mass of crystalline polyester resin PE-2, and 20 parts by mass of styrene acrylic. Resin SAc-1, 12 parts by mass of mold release agent (“Nissan Electol® WEP-8” manufactured by Nichiyu Co., Ltd., component: synthetic ester wax), and positively charged charge control agent (Orient Chemical Industries) 1 part by mass of "BONTRON (registered trademark) P-51" manufactured by Mitsubishi Chemical Industries Co., Ltd. and 9 parts by mass of a colorant ("MA100" manufactured by Mitsubishi Chemical Industries, Ltd., component: carbon black) were added. Then, using the FM mixer, the added toner material was mixed for 3 minutes at a rotation speed of 1200 rpm.

Subsequently, the obtained mixture was melt-kneaded using a twin-screw extruder (“PCM-30” manufactured by Ikegai Co., Ltd.) under the conditions of a material supply speed of 100 g / min, a shaft rotation speed of 150 rpm, and a cylinder temperature of 100 ° C. .. Then, the obtained melt-kneaded product was cooled. Subsequently, the cooled melt-kneaded product was roughly pulverized using a pulverizer (“Rohtoplex (registered trademark)” manufactured by Hosokawa Micron Co., Ltd.) under the condition of a set particle size of 2 mm. Subsequently, the obtained coarsely pulverized product was finely pulverized using a pulverizer (“Turbo Mill RS type” manufactured by Freund Turbo Co., Ltd.). Subsequently, the obtained finely pulverized product was classified using a classification machine (“Elbow Jet EJ-LABO type” manufactured by Nittetsu Mining Co., Ltd.). As a result, toner mother particles having a median volume diameter (D ₅₀ ) of 6.7 μm were obtained.

An FM mixer contains 100 parts by mass of the obtained toner mother particles and 1 part by mass of silica particles (“AEROSIL® REA90” manufactured by Nippon Aerosil Co., Ltd., silica particles imparted with positive charge by a surface treatment agent). (“FM-10B” manufactured by Nippon Coke Industries Co., Ltd.) was used to mix for 5 minutes under the conditions of a rotation speed of 3000 rpm and a jacket temperature of 20 ° C. As a result, the entire amount of the external additive (powder of silica particles) was adhered to the surface of the toner mother particles.

Subsequently, the obtained powder was sieved using a 200 mesh (opening 75 μm) sieve. As a result, toner TA-1, which is a positively charged toner, was obtained. The composition ratio of the components constituting the toner did not change before and after sieving.

[Preparation of toners TA-2 to TA-4 and TB-1 to TB-8]
The type of styrene acrylic resin to be charged into the FM mixer and the amount of styrene acrylic resin to be charged into the FM mixer are as shown in Table 1. Toners TA-2 to TA-4 and TB-1 to TB-8, respectively, were prepared.

Table 1 shows the type, input amount, specific IR ratio, and ΔSP value of the styrene acrylic resin used for each of the toners TA-1 to TA-4 and TB-1 to TB-8. In Table 1, the amount of the styrene acrylic resin charged was 100 parts by mass of the non-crystalline polyester resin PE-1, which was charged into the FM mixer (“FM-20B” manufactured by Nippon Coke Industries Co., Ltd.). The amount of resin (unit: parts by mass). The input amount of the styrene acrylic resin shown in Table 1 was the same as the amount of the styrene acrylic resin with respect to 100 parts by mass of the non-crystalline polyester resin PE-1 in the corresponding toner. The unit of the ΔSP value shown in Table 1 is “(cal / cm ³ ) ^1/2 ”.

<Evaluation method>
Hereinafter, the evaluation method of the toners TA-1 to TA-4 and TB-1 to TB-8 will be described.

[Preparation of two-component developer]
100 parts by mass of a carrier for "FS-C5250DN" manufactured by Kyocera Document Solutions Co., Ltd. and 8 parts by mass of toner (evaluation target: either toner TA-1 to TA-4 or TB-1 to TB-8). A two-component developer for evaluation was prepared by mixing for 30 minutes using a ball mill.

[Evaluation of hot offset resistance]
As the evaluation machine, a color printer (an evaluation machine in which the fixing temperature can be changed by modifying "FS-C5250DN" manufactured by Kyocera Document Solutions Co., Ltd.) was used. The two-component developer containing the toner to be evaluated prepared as described above was put into the black developing apparatus of the evaluation machine, and the toner to be evaluated was put into the black toner container of the evaluation machine.

Next, in an environment of a temperature of 23 ° C. and a humidity of 50% RH, the amount of toner loaded on an evaluation sheet (Mondy's "ColorCopy (registered trademark)", A4 size, basis weight 90 g / m ^{2) using the above evaluation machine.} Under the condition of 1.0 mg / cm ² , a solid image having a size of 25 mm × 25 mm (specifically, an unfixed toner image) was formed. Subsequently, the evaluation sheet on which the image was formed was passed through the fixing device of the evaluation machine. At this time, while raising the fixing temperature of the fixing device by 2 ° C. from 100 ° C., the presence or absence of hot offset was visually confirmed for each fixing temperature, and the maximum temperature at which hot offset did not occur (maximum fixing temperature) was measured. The presence or absence of the hot offset was determined based on whether or not there was stain on the evaluation paper due to the adhesion of toner to the fixing roller (dirt that appears at each rotation cycle of the fixing roller).

When the maximum fixing temperature was 200 ° C. or higher, it was evaluated as "excellent in hot offset resistance", and when the maximum fixing temperature was less than 200 ° C., it was evaluated as "not excellent in hot offset resistance".

[Evaluation of dash marks]
As the evaluation machine, a color multifunction device (“TASKalfa 5550ci” manufactured by Kyocera Document Solutions Co., Ltd.) was used. The two-component developer containing the toner to be evaluated prepared as described above was put into the black developing apparatus of the evaluation machine, and the toner to be evaluated was put into the black toner container of the evaluation machine.

Next, in an environment of a temperature of 23 ° C. and a humidity of 50% RH, a solid image having a size of 25 mm × 25 mm was printed on an evaluation sheet (manufactured by Mondi) under the condition of a ^{toner loading amount of 1.0 mg / cm 2 using the above evaluation machine.} 10,000 sheets were continuously printed on "ColorCopy (registered trademark)", A4 size, basis weight 90 g / m ^2).

Then, the presence or absence of the dash mark was visually confirmed on the solid image printed on the 10,000th sheet. When the dash mark was not confirmed (when there was no dash mark in the solid image), it was evaluated as "the occurrence of the dash mark could be suppressed". On the other hand, when a dash mark was confirmed (when there was a dash mark in the solid image), it was evaluated that "the occurrence of the dash mark could not be suppressed".

<Evaluation result>
Table 2 shows the maximum fixing temperature and the presence or absence of a dash mark for each of the toners TA-1 to TA-4 and TB-1 to TB-8.

The toner particles contained in each of the toners TA-1 to TA-4 contain toner mother particles containing a binder resin (non-crystalline polyester resin, crystalline polyester resin and specific styrene acrylic resin) and a mold release agent. Was there.

As shown in Table 1, in the toners TA-1 to TA-4, the amount of the specific styrene acrylic resin with respect to 100 parts by mass of the non-crystalline polyester resin was 20 parts by mass or more and 50 parts by mass or less. In the toners TA-1 to TA-4, the specific IR ratio was 0.40 or more and 0.70 or less.

As shown in Table 2, the maximum fixing temperature of the toners TA-1 to TA-4 was 200 ° C. or higher. Therefore, the toners TA-1 to TA-4 were excellent in hot offset resistance. There was no dash mark in the solid image printed using each of the toners TA-1 to TA-4 (specifically, in the solid image printed on the 10,000th sheet). Therefore, the toners TA-1 to TA-4 were able to suppress the generation of dash marks.

As shown in Table 1, in the toners TB-1 and TB-2, the amount of the specific styrene acrylic resin with respect to 100 parts by mass of the non-crystalline polyester resin was less than 20 parts by mass. In the toners TB-3 and TB-4, the amount of the specific styrene acrylic resin with respect to 100 parts by mass of the non-crystalline polyester resin exceeded 50 parts by mass. With the toners TB-5 and TB-6, the specific IR ratio was less than 0.40. In the toners TB-7 and TB-8, the specific IR ratio exceeded 0.70.

As shown in Table 2, the maximum fixing temperature of the toners TB-3 to TB-6 was less than 200 ° C. Therefore, the toners TB-3 to TB-6 were not excellent in hot offset resistance. There was a dash mark in the solid image printed using each of the toners TB-1 to TB-8 (specifically, in the solid image printed on the 10,000th sheet). Therefore, the toners TB-1 to TB-8 could not suppress the generation of dash marks.

From the above results, it was shown that according to the present invention, it is possible to provide a toner which is excellent in hot offset resistance and can suppress the occurrence of dash marks while containing an amorphous polyester resin as a binder resin.

The toner according to the present invention can be used for forming an image in, for example, a multifunction device or a printer.

Claims (5)

Toner containing toner particles
The toner particles contain toner mother particles containing a binder resin and a mold release agent.
The binding resin contains a non-crystalline polyester resin and a styrene acrylic resin.
The styrene acrylic resin has a first repeating unit represented by the following general formula (1) and a second repeating unit represented by the following general formula (2).
The amount of the styrene acrylic resin is 20 parts by mass or more and 50 parts by mass or less with respect to 100 parts by mass of the non-crystalline polyester resin.
In the infrared absorption spectrum of the styrene-acrylic resin obtained by infrared spectroscopic analysis, with respect to the absorbance of the maximum peak of wavenumber 3040cm ^-1 or 3074cm ^-1 following areas, the maximum peak of wavenumber 3075cm ^-1 or 3100 cm ^-1 following areas The absorbance ratio of the toner is 0.40 or more and 0.70 or less.

(In the general formula (1), R ¹¹ and R ¹² each independently represent a hydrogen atom, a halogen atom, or an alkyl group having 1 or more and 6 or less carbon atoms.
R ¹³ , R ¹⁴ , R ¹⁵ , R ¹⁶ and R ¹⁷ each independently represent a hydrogen atom, a halogen atom, a hydroxyl group, or an alkyl group having 1 or more and 6 or less carbon atoms.
However, ^{at least one of R 13} , R ¹⁴ , R ¹⁵ , R ¹⁶ and R ¹⁷ represents a hydrogen atom. )

(In the general formula (2), R ²¹ and R ²² independently represent a hydrogen atom, a halogen atom, or an alkyl group having 1 or more and 6 or less carbon atoms.
R ³ represents an alkylene group having 1 or more and 6 or less carbon atoms.
R ⁴ and R ⁵ each independently represent a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.
However, ^{at least one of R 4} and R ⁵ represents an alkyl group having 1 to 6 carbon atoms. ) The first repeating unit is a repeating unit derived from styrene, and is a repeating unit.
The toner according to claim 1, wherein the second repeating unit is a repeating unit derived from 2- (dimethylamino) ethyl acrylate. The toner according to claim 1 or 2, wherein the styrene acrylic resin further has a third repeating unit derived from divinylbenzene. The toner according to any one of claims 1 to 3, wherein the amount of the release agent is 7 parts by mass or more with respect to 100 parts by mass of the binder resin. When the SP value of the non-crystalline polyester resin is SP _E and the SP value of the styrene acrylic resin is SP _S , the relationship of | SP _E −SP _S | ≦ 1.2 (cal / cm ³ ) ^1/2. The toner according to any one of claims 1 to 4, which satisfies the above conditions.